Sintakote Design Manual Nov Edition

SINTAKOTE®

Steel pipelinesystemsDesign Manual

SINTAKOTESteel pipelinesystemsDesign Manual

Tyco Water Regional Marketing Offices

Divisional Office

Tyco Water Pty Ltd

ABN 75 087 415 745

ACN 087 415 745

Dursley Road

Yennora 2161

PO Box 141 Fairfield

New South Wales 1860

Telephone 61 2 9721 6600

Facsimile 61 2 9721 6601

[email protected]

www.tycowater.com

RegionalMarketing Offices

Brisbane

39 Silica Street

Carole Park 4300

PO Box 162 Carole Park

Queensland 4300

Telephone 07 3712 3625

Facsimile 07 3271 3128

[email protected]

Sydney

Dursley Road

Yennora 2161

PO Box 141 Fairfield

New South Wales 1860



[email protected]

Melbourne

60A Maffra Street

Coolaroo 3048

PO Box 42 Dallas

Victoria 3047



[email protected]

Perth

45 Guthrie Street

Osborne Park 6017

PO Box 1495 Osborne Park BC

Western Australia 6916



[email protected]

This manual has been prepared by Tyco Water to assistqualified engineers and contractors in the selection of theCompany’s product, and is not intended to be an exhaustivestatement on pipeline design, installation or technical matters.Any conclusions, formulae and the like contained in the manualrepresent best estimates only and may be based onassumptions which, while reasonable may not necessarily becorrect for every installation.

Successful installation depends on numerous factors outsidethe Company’s control, including site preparation andinstallation workmanship. Users of this manual must checktechnical developments from research and field experience,and rely on their knowledge, skill and judgement, particularlywith reference to the qualities and suitability of the productsand conditions surrounding each specific installation.

The Company disclaims all liability to any person who relies onthe whole or any part of this manual and excludes all liabilityimposed by any statute or by the general law in respect of thismanual whether statements and representation in this manual

are made negligently or otherwise except to the extent it isprevented by law from doing so.

The manual is not an offer to trade and shall not form any partof the trading terms in any transaction. Tyco Water’s tradingterms contain specific provisions which limit the liability of Tyco Water to the cost of replacing or repairing any defectiveproduct.

SINTAKOTE®, SINTAJOINT® and SINTAPIPE® are registeredtrademarks.

© Copyright Tyco Water Pty Ltd

This manual is a publication of Tyco Water Pty Ltd, ABN 75 087 415 745 / ACN 087 415 745, and must not becopied or reproduced in whole or part without the Company’s prior written consent.

This manual is and shall remain as the Company’s property andshall be returned to the company on its request. The Company reserves the right to make changes to anymatter at any time without notice.

Steel Pipeline Systems Design Manual

First Edition 1992Second Edition 2003Third Edition 2004

C O N T E N T S

Section 1 Introduction 8

Section 2 Technical Specifications and Manufacturing Standards 12

Section 3 Coatings 16

Section 4 Linings 22

Section 5 Pipe Data 26

Section 6 Jointing Systems 36

Section 7 Fittings 44

Section 8 Design – General Considerations 48

Section 9 Structural Properties of Pipe 58

Section 10 Hydraulic Characteristics of Pipe and Fittings 70

Section 11 Water Hammer 80

Section 12 Anchorage of Pipelines 88

Section 13 Structural Design for Buried Pipelines 94

Section 14 Free Span and Structural Loading 102

Section 15 Appurtenance Design 114

Section 16 Typical Installation Conditions 118

Appendices 126

Appendix A Glossary 128

Appendix B SI Conversion Factors 132

Appendix C Material Properties 135

Appendix D References 136

Appendix E Standards Referenced in Text 137

Introduction

8

section1

1.1 Steel design manualOur communities today depend heavily on the continual supply ofhigh quality water for both domestic and industrial purposes.

For these applications the community requires a pipeline that willdeliver good quality water in sufficient quantity and with adequatepressure, year after year.

This must be achieved under prevalent operating conditionsembracing static and transient operating pressures and externalloads acting on the pipeline, including earth pressure and live loadsdue to vehicular traffic.

Satisfaction of these criteriaTo perform as required the pipeline system must not only becapable of being handled, transported and installed with little or no damage but also must be resistant to degradation or damagethrough corrosion, ageing and other external effects.

The community expects these criteria to be met in the most economical way, that is at minimum cost over the lifetime of the pipeline.

The superior material properties of steel, combined with world-class corrosion protection systems, ensure that Tyco Water SteelPipeline Systems provide the answer for water supply and manyother applications.

1.2 HistoryThroughout Australia and the rest of the world, steel pipelines havelong been used in water supply, particularly where high pressures,difficult laying conditions or security of supply, have required thestrength and toughness of steel.

Tyco Water and its predecessors have traditionally been at theforefront of developments in the water industry. Today, Tyco Water’s products and services cover a broad range of industry needs, offering a total solution approach to its Customers. Tyco Water’s operations extend across Australia, South East Asiaand the Pacific.

1.3 ApplicationsTyco Water Steel Pipeline Systems, (TWSPS), offers products for allwater industry applications, including:

• potable water systems,

• industrial water systems,

• sewage rising mains and trunk sewers.

Products are also available for other applications including:

• slurry pipelines,

• aggressive fluids, and

• tubular piling and structural applications.

1.4 Installation trainingExtensive research has shown that by following proper installationprocedures, Tyco Water Steel Pipeline Systems can readily achieveoperational lifetimes of over 100 years.

Tyco Water and its predecessors have promoted quality pipelineinstallation through its “SINTAKOTE PIPELINES PROGRAM”. This provides training in the installation of steel pipe andaccreditation to competent pipeline laying personnel. Most Australian water authorities now regard this as a mandatorycompetency requirement.

Tyco Water Training is a Registered Training Organisation (RTO).The course has been designed to meet some outcomes of theNTIS Unit of Competency UTWNSWS390A/02 – Construct/installdrains, pipes and associated fittings, and is accredited to theVocational Education and Training Board (NSW).

1.5 Manufacture of mild steel cement mortar lined (MSCL) pipeTyco Water Pty Ltd manufactures MSCL pipe using the spiralforming method. In this process, a coil of steel having the requiredwidth and thickness is placed on the spiral pipe-making machine,where it is uncoiled and fed continuously through the machine. The strip is formed to the required pipe diameter and continuouslywelded internally and externally using the Submerged Arc Weldingprocess. The welds so produced form a spiral, hence the name ofthe process.

The pipe so formed is then fed onto the output table where it is cutto the length required. The pipe is then removed from the machineto an area where each pipe is inspected.

After inspection, the pipe ends are machined square beforeproceeding to the pipe end-forming machine. Here the ends of thepipe are formed to produce the socket for the SINTAJOINT® rubberring joint or the spigot and socket for the Ball and Socket Joint (B & S).The SINTAJOINT end is formed by rolling the shape on the pipeends. The socket and spigot of the B & S joint are formed byexpansion. Spherical Slip-in Joint ends (SSJ) are formed byexpanding and collapsing the ends on specially made dies on thehydrostatic testing machine.

10 | S E C T I O N 1

Each pipe is then hydrostatically tested. Water is pumped into thepipe whilst all air is purged out. When the pipe is full of water, thepressure is increased so as to induce a hoop stress in the pipeshell equivalent to 90% of the nominal minimum yield strength(MYS) of the steel that the pipe is made from, as required byAS1579. Note that the maximum pressure that can be applied islimited to 8.5 MPa, as dictated by the pressure test equipment.

After testing, the pipe is dried and the external surface is blastcleaned to remove all rust and mill scale prior to application of theexternal corrosion protection system (SINTAKOTE®). Note that forSINTAPIPE®, the internal surface of the pipe is also blast cleaned at this stage.

The pipe is then placed into a preheat oven where the temperatureof the steel is raised to processing temperature. It is then pickedup and dipped into a fluidised bath containing polyethylenepowder. On contact, the powder melts and fuses to the pipe’sexternal surface. This pipe is rotated and held in the bath until therequired coating thickness is reached. This is the SINTAKOTEfusion bonding process.

For SINTAPIPE, the internal lining and external coating operationsare carried out simultaneously.

For SSJ and B & S pipes, the external coating is set back from theends of the pipe to allow for field jointing and welding. In the caseof SINTAJOINT pipe, the external coating is carried around theends of the spigot and socket to actually cover part of the internalsurface of the pipe at each end.

After coating, pipes are cement mortar lined. The pipe is spun at high speed so as to generate a high ‘g’ force. This centrifugal force compacts the mortar around the insidesurface of the pipe whilst removing excess water from themortar. The process results in a dense and firm lining. For field assembly the lining is set back from the ends asrequired by AS1281. After the lining operation the pipe isremoved from the machine and placed on curing ramps. Each pipe is fitted with plastic end-caps in order to protectagainst the formation of shrinkage cracks, caused by rapiddrying. The SINTAKOTE is checked to ensure that no damagehas occurred and that it is free from holes in the coating, known as ‘holidays’.

The pipe is stored for a minimum period of four days to ensureadequate cure before dispatch. During this period, the plastic endcovers are retained to prevent loss of moisture from the lining.

The completed SINTAJOINT pipe is rubber ring jointed, withSINTAKOTE applied externally and around the pipe ends, allowingthe cement mortar lining to overlap the SINTAKOTE. The pipe is

completely protected with the factory applied SINTAKOTE andcement mortar lining. It requires no field joint coating or lining.

Pipes and fittings are manufactured in accordance with the relevantAustralian Standard. Each production plant operates under acertified Quality Assurance system to AS/NZS ISO 9001 / 9002.

Tyco Water can also provide other types of coatings and linings,e.g. epoxy paint, seal coatings etc, to suit the client’s requirements.

Short runs of pipe can also be made using bending rolls to formcans that are then welded together to form specific lengths of pipe.Pipe fittings, such as mitre bends, off-takes, bifurcations etc. arealso available.

Tyco Water supplies a range of pipe from 114mm to 2500mm OD.The wall thickness ranges from 4mm to 16mm and lengths can bemade in 6, 9, 12.2 and 13.5m. Please contact your nearestRegional Marketing Office for further details.

S E C T I O N 1 | 11

Preparation of pipe ends at the end trimming station.

S E C T I O N 1

Introduction

TechnicalSpecifications &ManufacturingStandards

12

section2

2.1 SteelSteel pipe and fittings for water pipe are manufactured in accordancewith the following Australian Standards:

AS 1594: “Hot-rolled steel flat products”AS 3678: “Hot-rolled structural steel plates, floor plates and slabs”

Steel pipe for the Water Industry is usually specified in wall thicknesses from 4.0 to 12.7mm. The analysis grades HXA1016 steel toAS1594 are normally used. HXA1016 materials are supplied by the steel maker with prescribed chemical analysis limits.The mechanical property values associated with the chemical analysishave been identified by statistical means and are given in Section 8.5Table 8.4.

For a thickness greater than 12.7mm, steel to AS3678 is usuallyused with a minimum yield strength (MYS) of 250 MPa.

Other grades of steel can be specified provided that the carbonequivalent (CE) calculated by using the following equation does notexceed 0.40%:

CE =%C + %Mn + %Cr+%Mo+%V + %Ni+%Cu ≤ 0.40% 6 5 15

Refer to AS 1579 for further details.

2.2 Steel pipe manufactureAS 1579: “Arc welded steel pipes and fittings for water and waste water”.

Pipe manufactured by Tyco Water must pass a mandatoryhydrostatic pressure test in accordance with AS1579, ensuringfitness for purpose and quality of manufacture.

2.3 SINTAKOTEAS 4321: “Fusion bonded medium density polyethylene coatings and linings for pipes and fittings”.

2.4 Cement mortar liningAS 1281: “Cement mortar lining of steel pipes and fittings”.

2.5 SINTAJOINT rubber ringsAS 1646: “Elastomeric seals for waterworks purposes”.

2.6 Other materials and specificationsOther materials and specifications can be accommodated if required.Please contact your nearest Tyco Water Regional Marketing Office forfurther details.

S E C T I O N 2

Technical Specifications and Manufacturing Standards

S E C T I O N 2 | 15

Coatings

16

section3

18 | S E C T I O N 3

3.1 Brief historyA wide variety of systems have been used to provide externalcorrosion protection of steel water supply pipelines, for both aboveground and below ground installations.

Above ground treatments have consisted of various types of industrialpaints such as inorganic zinc silicates and epoxies. For undergroundapplications bitumen paints were commonly used in the early days.

Coal tar enamel became the preferred coating in the 1950’s.

Its properties were enhanced by incorporating glass fibre mat andan outer wrapping of coal tar impregnated felt. Coal tar enamelwas in common use for underground applications through the1960’s and 1970’s and into the early 1980’s.

Coal tar enamel generally performed well. However there wereoccasional problems during storage, handling and deterioration inservice. Tyco Water carried out extensive research to develop animproved system, the result of which was the introduction of

Table 3.1 – SINTAKOTE (fusion bonded medium density polyethylene) - Properties & performance

Property Test standards Typical test results

Coating Material AS 4321 Complies

Colour Black: To impart maximum protection against UV radiation when used above ground

Service Temperature Range AS 4321 -40°C to 70°C

Thermal Stability (100°C for 100 days) AS 4321 < 35% change in MFI

Bond Strength AS 4321 5-10 N/mm

Tensile Strength at Yield AS 4321 18 MPa

Indentation Hardness ASTM D2240 61 Shore hardness D

Penetration resistance - 23°C AS 4321 0.1mm indentation- 70°C 0.2mm indentation

Thermal Conductivity ASTM C177 0.34 Wm-1 K-1

(Compression moulded specimen)

Environmental Stress Crack Resistance AS 4321 F50 >100 hrs

Density AS 4321 940 kg/m3

Water Absorption AS 4321 < 0.1% m/m water absorbed(100 days, 23°C)

Electrical Volume Resistivity IEC 60093 approx. 1019 ohm cm (1000 sec. polarisation, on base polymer)

Dielectric Strength IEC 60243 20kV/mm (on base polymer, (Specimen 3mm thick, on base polymer) without carbon black)

Impact Resistance ASTM G13, 219mm No holidays after 10 successive drops(Limestone drop test) OD coated pipe, av.

thickness 1.6mm

Impact Resistance AS 4321/ASTM G14, Mean impact strength 20J(Falling tup test) 219mm OD coated pipe,

2.3mm thick

Abrasion Resistance ASTM D4060 8mg loss due to abrasion(Tabor) (C17, 1000g, 1000 cycles)

Cathodic Disbondment AS 4321 8-14mm radial disbonded length

Chemical Resistance: SINTAKOTE is resistant to all the normal chemicals, compounds and solutions commonly encountered in waterindustry applications including muriatic acids, as well as marine organisms and compounds found in aggressive soils.

S E C T I O N 3 | 19

Table 3.2. – SINTAKOTE - Coating and Lining Thickness (millimetres)

SINTAKOTE® in 1972. Once the performance of this coating wasrecognised, coal tar enamel was progressively phased out.

3.2 SINTAKOTE®

SINTAKOTE is a registered trademark. A black polyethylene coatingis fusion bonded directly to the steel pipe, hence the coating is alsoknown as Fusion Bonded Polyethylene (FBPE). Properties andperformance under various test standards are given in Table 3.1.

Features of the coating include:

• Excellent adhesion• High impact and load resistance• Excellent chemical resistance• High dielectric strength• High electrical resistivity• Low water absorption• Resistance to soil stresses• Wide service temperature range - temperatures from minus 40°C to plus 70°C have no detrimental effect on SINTAKOTE• Ability to accept cold bending of the pipe in accordance with AS 2885 without damage to the coating.

SINTAKOTE is ideally suited to below ground applications, including installations where pipes must be thrust bored under roadsand railways. It is also ideal for sub-sea installations such as theprotection of tubular steel wharf piling.

SINTAKOTE is supplied in accordance with AS 4321: “Fusion-bonded medium-density polyethylene coating and lining for pipes and fittings”.

The SINTAKOTE processThe bare steel surface of the pipe is cleaned and profiled by grit blastingto ensure an excellent bond between the steel and the coating. The pipeis then heated in an oven and dipped into a fluidised bath ofpolyethylene powder that fuses directly onto the heated surface.

The recommended thickness of the coating varies with the diameterof the pipe. See Table 3.2.

The molten SINTAKOTE can be strewn with sand to provide a shearkey for concrete encasement when requested.

A range of conventional fittings can be coated in a similar manneras the pipe itself to achieve the same high quality finished coating.

Quality control is maintained through routine tests for thickness,adhesion and coating continuity.

RepairsMinor damage may occur when SINTAKOTE pipe is mishandled.Such damage can be repaired using a particular method suited tothe area of the damaged section. Small areas can be repaired bythe application of a patch whereas large areas are repaired by theapplication of tapes or heat shrinkable polyethylene sleeves. Detailsare given in the SINTAKOTE Steel Pipeline Systems “Handling andInstallation Reference Manual” available from any of our RegionalMarketing Offices.

Note: Oxygen and acetylene should not be used to heat SINTAKOTEas heating in this way can degrade SINTAKOTE.

Cathodic protectionCathodic protection (CP) is a method of providing secondarycorrosion protection to coated pipelines. High-pressure oil and gaspipelines are protected by CP as the danger and costs of leaks areso high that secondary protection is required by statutoryauthorities.

Most water pipelines that utilise SINTAJOINT pipes are notcathodically protected. The choice of cathodic protection for waterpipelines is one of strategic importance and cost. When usingSINTAJOINT pipe it is likely to be more cost effective not to applycathodic protection. Normal CP costs include joint bonding cables,anodes, ground-beds, transformer rectifiers and associatedinstallation and maintenance.

Pipe outside Minimum thicknessdiameter

Coating LiningElastomeric ring

(Note 1) joint region (Note 2)

≤ 273 (250 DN) 1.6 1.0 (Note 3)

>273 ≤ 508 (500 DN)` 1.8 1.0 0.8

>508 ≤ 762 (750 DN) 2.0 1.0 1.0

>762 2.3 1.0 1.0

Notes: 2 See Figure 3.1 for joint region.1 Nominal pipe sizes are shown in brackets. 3 RRJ available for ≥324mm OD.

S E C T I O N 3

Coatings

20 | S E C T I O N 3

CP is however, completely compatible with SINTAKOTE. The high electrical resistivity of SINTAKOTE is maintained duringits life due to the very low water absorption of SINTAKOTE. Its high resistance to impact and deterioration whilst in servicemake it the ideal coating choice for critical installations where CP is deemed essential.

Handling, storing and layingSINTAKOTE pipes should be cradled and packed using appropriatedunnage.

The FBPE will remain unaffected when stored above ground over alengthy period of time due to the inbuilt ultra violet stabiliser, as wellas its high resistance to temperature.

Because of the strength, toughness and damage resistance ofSINTAKOTE the bedding, backfill composition and compactionprocedures are not as critical as those for alternative coatings.Please refer to the SINTAKOTE Steel Pipelines Handling andInstallation Reference Manual for further details.

Chemical resistance SINTAKOTE is resistant to all the relevant chemicals, compoundsand solutions commonly encountered in water industry applicationsincluding muriatic acids, as well as marine organisms andcompounds found in aggressive soils.

SINTAKOTE thicknessSINTAKOTE coating and lining thicknesses conform to AS 4321. See Table 3.2 and Fig. 3.1.

Figure 3.1: Designation of SINTAJOINT joint region.

Lining

Lining

Coating

Coating

Joint region

Joint region

S E C T I O N 3 | 21

Linings

22

section4

24 | S E C T I O N 4

4.1 GeneralFerrous potable water pipelines will corrode internally if not protected.The rate of corrosion is generally quite low due to the lowconductivity, neutral pH and low dissolved oxygen content of potablewater.

Internal corrosion does not usually lead to pipe failure, but can resultin head loss or reduced flow due to an increase in surface roughnesscaused by the growth of corrosion products. Water quality can alsobe a problem due to increased concentrations of iron in the water.

The predominant lining used for potable water and sewage risingmains is cement mortar lining. Cement mortar lining is not suitablefor sewage pipelines that are septic and produce sulphuric acid. Note that pipelines can be designed to minimise the generation ofsulphuric acid (see ref. 7). Pipe with alternative linings, such asSINTAPIPE® described in Section 4.3, or Calcium Aluminate (CA)cement mortar lining provide suitable protection against acid attack.

Cement mortar linings are often used to convey petroleum productsfrom ships and the pipelines are usually left filled with seawater whennot in use.

Other common applications include bore field collectors and groundwater transmission lines.

For high saline applications where total dissolved solids exceed35,000 ppm or aggressive water conveyance, customers shouldcontact Tyco Water Marketing Offices.

4.2 Cement mortar lining

HistoryCement mortar has been used to line pipe since the 1840’s when itwas introduced in France and the USA. The techniques forapplication took some time to develop and it was not until the 1920’sthat the process of centrifugal spinning (originally known as the‘Hume’ process) came into being. This process allowed the rapidapplication of linings to the entire pipe surface by placing a mixture ofsand, cement and water into the pipe and rotating it at high speed.

The centrifugal forces distribute the lining around the pipecircumference and compact it against the pipe wall. At the sametime excess water in the mixture migrates to the surface of the lining.After spinning, this excess water is removed leaving a smoothsurfaced mortar with a water to cement ratio of 0.25 to 0.40.

The high density, low void content and low water content results in astrong, low permeability cement mortar lining.

Current practiceThe centrifugally spun process remains the preferred lining method

today as it produces the highest quality lining. It is the method usedin all our steel pipe plants.

Cement mortar linings provide long-term protection at a low cost and consequently they remain the standard lining for potablewater mains.

Mechanism of corrosion protectionCement mortar linings provide active protection of the steel pipe bycreating a high pH environment, typically pH12, at the steel-mortarinterface. At pH values above approximately 9, a stable hydroxidefilm is formed on the inside steel surface. While this passive filmremains intact no corrosion occurs.

Lining appearanceWhen leaving our pipe manufacturing plants the linings may containsuperficial hairline cracks. If the pipes are stored for extendedperiods, say more than two months, especially in hot weather, dryingshrinkage can lead to the formation of larger cracks.

For potable water pipelines cracks up to 2mm wide should not berepaired as they will close and heal when immersed in water. Whenthe pipes are rewetted, the mortar typically absorbs up to 8%

Pipe OD (mm) CML (mm) Tolerance (mm) +/-

100 F OD F 273 9 3

273 < OD F 762 12 4

762 < OD F1219 16 4

1219 < OD F 1829 19 4

Chemical species Tolerable TolerableConcentration Concentrationfor SR Cement for CA Cement(mg/L) (mg/L)

Sulphate, SO42- 5000 max no limit

Magnesium, Mg2+ 300 max no limit

Free aggressive carbon dioxide, CO2 30 no limit

pH 6.0 min 4.0 min

Ammonium, NH4+ 30 max no limit

Calcium, Ca2+ 1.0 min no limit

Hydrogen Sulphide, S 0.5 max 10 max

Table 4.2 - Chemical resistance of cement mortar linings

Table 4.1 - Cement mortar lining (CML) thicknesses

S E C T I O N 4 | 25

moisture and expands, reducing crack widths by around 50%.Further hydration closes the cracks in a process sometimes referredto as autogenous healing.

The mechanism of high pH providing protection and the ability ofcement mortar to continue to hydrate and cure during servicemeans that minor cracks in the lining can be tolerated. However, for aggressive conveyants the 2mm maximum crack width mayneed to be reduced.

Cement mortar lining (CML) thicknessesCement mortar linings are manufactured to the thicknesses andtolerances contained in AS 1281. See Table 4.1.

PerformanceThe dense mortar produced by our centrifugal lining processoffers good chemical resistance to potable waters and can also beused in saline and wastewater applications. Cement mortar liningusing Sulphate resistant (SR) and Calcium Aluminate (CA) cementsare resistant to the water chemistries shown in Table 4.2. Ordinarypotable cement performs similarly to SR cement, except the limiton sulphate concentration is reduced to 500 mg/L. Note that CACshould not be used for potable water pipelines. When the waterchemistry is outside these limits, please discuss with a Tyco WaterRegional Marketing Office.

Bitumen seal coatHigh pH can develop in water, especially in small diameter cement

mortar lined pipelines, where the water is aggressive and the flow rate is low, resulting in a long residence time. To overcome this potential problem seal coatings have beendeveloped to restrict leaching from the cement mortar lining.

Pipes can be supplied with cement mortar lining and bitumen sealcoat if required. This must be specified at time of quotation.

Handling, storing, layingCement mortar lined pipes should be handled with due care.Mistreatment, poor handling and unloading practice can result inlining damage.

Details of repair are given in the SINTAKOTE Steel PipelineSystems “Handling and Installation Reference Manual” availablefrom any of our Tyco Water Regional Marketing Offices.

4.3 SINTAPIPE®

SINTAPIPE® is a registered trademark. SINTAKOTE is applied to both the outside and the bore of rubber ring jointed steel pipe to make SINTAPIPE. Possible because of innovation in the fusion bonding processes, it provides a wide range ofopportunities for steel pipe options for aggressive water applications.

SINTAPIPE properties and performance under various teststandards are given in Table 3.1.

SINTAKOTE pipe crossing the Bli Bli Bridge in Queensland.

S E C T I O N 4

Linings

Pipe Data

26

section5

28 | S E C T I O N 5

5.1 Preferred sizes and dimensionsTable 5.1 contains a comprehensive range of pipe diameters andwall thicknesses supplied by Tyco Water.

For details of pipe diameters and wall thicknesses most readily availableand for pipe diameters in excess of 2200mm nominal bore, clients areadvised to contact Tyco Water Regional Marketing Offices.

Steel wall thicknessesPlease note steel wall thicknesses shown in Table 5.1 represent platethicknesses supplied by the steel maker as “preferred thicknesses”.

Intermediate and greater wall thicknesses can be supplied butthese may incur additional costs and longer lead times.

5.2 Hydraulic boresHydraulic bores are given in Table 5.1 with CML bores based onmean cement mortar lining thicknesses given in Table 4.1.

5.3 Pipe massesTo calculate masses per metre for pipes with dimensions notincluded in the tables use the following formulae:

Plain steel shell: M1 = 0.02466(D-t)t kg/m

Cement mortar lining: M2 = 0.00755T(D-2t-T) kg/m

SINTAKOTE: M3 = 0.00295Dts kg/m

where:D = outside diameter of steel shell mmt = steel wall thickness mmT = cement mortar lining thickness mmts = SINTAKOTE thickness mm

Approximate material densities used in these formulae are:Steel: 7850 kg/m3

Cement mortar: 2400 kg/m3

SINTAKOTE: 940 kg/m3

5.4 Pipe lengthsPipes are normally supplied in 6, 9, 12.2 and 13.4m effective laying lengths.

Minimum length is usually 6 metres, such pipes being used tofacilitate road crossings in busy areas as well as to allow minorchanges in direction without the need to provide fittings.

Lengths in excess of 13.5 metres can be manufactured upon request.

5.5 Buoyant weights (empty, closed submerged weight)Table 5.2 lists masses of water filled pipes and buoyant weights ofpipes. Where buoyant weight values are negative, precautionsshould be taken against flotation effects on empty pipelines,particularly during construction. The density of water used in thecalculation of these tables is 1000 kg/m3.

Grit blasting in preparation for SINTAKOTE application.

S E C T I O N 5 | 29

Section Dimensions Pipe Bore Mass/metre Mass/Pipe

Steel Shell CML SK Steel CML Steel CML SK Total Pipe Length

OD t T ts M1 M2 M3 MTOT 6m 9m 12.2m 13.5m

mm mm mm mm mm mm kg/m kg/m kg/m kg/m Tonne Tonne Tonne Tonne114 4.8 9 1.6 104 86 12.9 6.5 0.5 19.9 0.12168 4.5 9 1.6 159 141 18.1 10.2 0.8 29.1 0.17 0.26168 5 9 1.6 158 140 20.1 10.1 0.8 31.0 0.19 0.28190 4.5 9 1.6 181 163 20.6 11.7 0.9 33.2 0.20 0.30190 5 9 1.6 180 162 22.8 11.6 0.9 35.3 0.21 0.32

219 5 9 1.6 209 191 26.4 13.6 1.0 41.0 0.25 0.37240 5 9 1.6 230 212 29 15.0 1.1 45.1 0.27 0.41257 5 9 1.6 247 229 31.1 16.2 1.2 48.5 0.29 0.44273 5 9 1.6 263 245 33 17.3 1.3 51.6 0.31 0.46290 5 12 1.8 280 256 35.1 24.3 1.5 61.0 0.37 0.55

305 5 12 1.8 295 271 37 25.6 1.6 64.3 0.39 0.58324 5 12 1.8 314 290 39.3 27.4 1.7 68.4 0.41 0.62324 6 12 1.8 312 288 47.1 27.2 1.7 76.0 0.46 0.68337 5 12 1.8 327 303 40.9 28.5 1.8 71.3 0.43 0.64337 6 12 1.8 325 301 49 28.4 1.8 79.1 0.47 0.71356 5 12 1.8 346 322 43.3 30.3 1.9 75.4 0.45 0.68356 6 12 1.8 344 320 51.8 30.1 1.9 83.8 0.5 0.75

406 5 12 1.8 396 372 49.4 34.8 2.2 86.4 0.52 0.78 1.05406 6 12 1.8 394 370 59.2 34.6 2.2 96.0 0.58 0.86 1.17419 5 12 1.8 409 385 51.0 36.0 2.2 89.2 0.54 0.80 1.09419 6 12 1.8 407 383 61.1 35.8 2.2 99.1 0.59 0.89 1.21457 5 12 1.8 447 423 55.7 39.4 2.4 97.6 0.59 0.88 1.19457 6 12 1.8 445 421 66.7 39.2 2.4 108.4 0.65 0.98 1.32457 8 12 1.8 441 417 88.6 38.9 2.4 129.9 0.78 1.17 1.58457 10 12 1.8 437 413 110.2 38.5 2.4 151.2 0.91 1.36 1.84

502 5 12 1.8 492 468 61.3 43.5 2.7 107.4 0.64 0.97 1.31 1.45502 6 12 1.8 490 466 73.4 43.3 2.7 119.4 0.72 1.07 1.46 1.61502 8 12 1.8 486 462 97.5 42.9 2.7 143.1 0.86 1.29 1.75 1.93508 5 12 1.8 498 474 62.0 44.0 2.7 108.8 0.65 0.98 1.33 1.47508 6 12 1.8 496 472 74.3 43.9 2.7 120.8 0.72 1.09 1.47 1.63508 8 12 1.8 492 468 98.6 43.5 2.7 144.8 0.87 1.30 1.77 1.96508 10 12 1.8 488 464 122.8 43.1 2.7 168.6 1.01 1.52 2.06 2.28559 5 12 2.0 549 525 68.3 48.7 3.3 120.3 0.72 1.08 1.47 1.62559 6 12 2.0 547 523 81.8 48.5 3.3 133.6 0.80 1.20 1.63 1.80559 8 12 2.0 543 519 108.7 48.1 3.3 160.1 0.96 1.44 1.95 2.16559 10 12 2.0 539 515 135.4 47.7 3.3 186.4 1.12 1.68 2.27 2.52

610 5 12 2.0 600 576 74.6 53.3 3.6 131.5 0.79 1.18 1.60 1.77610 6 12 2.0 598 574 89.4 53.1 3.6 146.1 0.88 1.31 1.78 1.97610 8 12 2.0 594 570 118.8 52.7 3.6 175.1 1.05 1.58 2.14 2.36

Table 5.1 – Pipe Data

S E C T I O N 5

Pipe Data

30 | S E C T I O N 5




mm mm mm mm mm mm kg/m kg/m kg/m kg/m Tonne Tonne Tonne Tonne

610 10 12 2.0 590 566 148 52.4 3.6 203.9 1.22 1.84 2.49 2.75648 5 12 2.0 638 614 79.3 56.7 3.8 139.8 0.84 1.26 1.71 1.89648 6 12 2.0 636 612 95.0 56.5 3.8 155.4 0.93 1.40 1.90 2.10648 8 12 2.0 632 608 126.3 56.2 3.8 186.3 1.12 1.68 2.27 2.51648 10 12 2.0 628 604 157.3 55.8 3.8 217.0 1.30 1.95 2.65 2.93660 5 12 2.0 650 626 80.8 57.8 3.9 142.5 0.85 1.28 1.74 1.92660 6 12 2.0 648 624 96.8 57.6 3.9 158.3 0.95 1.42 1.93 2.14660 8 12 2.0 644 620 128.6 57.3 3.9 189.8 1.14 1.71 2.32 2.56660 10 12 2.0 640 616 160.3 56.9 3.9 221.1 1.33 1.99 2.70 2.98

700 5 12 2.0 690 666 85.7 61.4 4.1 151.3 0.91 1.36 1.85 2.04700 6 12 2.0 688 664 102.7 61.2 4.1 168.1 1.01 1.51 2.05 2.27700 8 12 2.0 684 660 136.5 60.9 4.1 201.5 1.21 1.81 2.46 2.72700 10 12 2.0 680 656 170.2 60.5 4.1 234.8 1.41 2.11 2.86 3.17711 5 12 2.0 701 677 87.0 62.4 4.2 153.7 0.92 1.38 1.87 2.07711 6 12 2.0 699 675 104.3 62.2 4.2 170.8 1.02 1.54 2.08 2.31711 8 12 2.0 695 671 138.7 61.9 4.2 204.8 1.23 1.84 2.50 2.76711 10 12 2.0 691 667 172.9 61.5 4.2 238.6 1.43 2.15 2.91 3.22762 5 12 2.0 752 728 93.3 67.0 4.5 164.9 0.99 1.48 2.01 2.23762 6 12 2.0 750 726 111.9 66.9 4.5 183.2 1.10 1.65 2.24 2.47762 8 12 2.0 746 722 148.7 66.5 4.5 219.8 1.32 1.98 2.68 2.97762 10 12 2.0 742 718 185.4 66.1 4.5 256.1 1.54 2.30 3.12 3.46

800 5 16 2.3 790 758 98.0 93.5 5.4 197.0 1.18 1.77 2.40 2.66800 6 16 2.3 788 756 117.5 93.3 5.4 216.2 1.30 1.95 2.64 2.92800 8 16 2.3 784 752 156.2 92.8 5.4 254.5 1.53 2.29 3.10 3.44800 10 16 2.3 780 748 194.8 92.3 5.4 292.6 1.76 2.63 3.57 3.95813 5 16 2.3 803 771 99.6 95.1 5.5 200.2 1.20 1.80 2.44 2.70813 6 16 2.3 801 769 119.4 94.8 5.5 219.8 1.32 1.98 2.68 2.97813 8 16 2.3 797 765 158.8 94.3 5.5 258.7 1.55 2.33 3.16 3.49813 10 16 2.3 793 761 198.0 93.9 5.5 297.4 1.78 2.68 3.63 4.02889 5 16 2.3 879 847 109.0 104.3 6.1 219.3 1.32 1.97 2.68 2.96889 6 16 2.3 877 845 130.6 104.0 6.1 240.7 1.44 2.17 2.94 3.25889 8 16 2.3 873 841 173.8 103.5 6.1 283.4 1.70 2.55 3.46 3.83889 10 16 2.3 869 837 216.8 103.0 6.1 325.9 1.96 2.93 3.98 4.40895 5 16 2.3 885 853 109.7 105.0 6.1 220.8 1.32 1.99 2.69 2.98895 6 16 2.3 883 851 131.5 104.7 6.1 242.4 1.45 2.18 2.96 3.27895 8 16 2.3 879 847 175.0 104.3 6.1 285.3 1.71 2.57 3.48 3.85895 10 16 2.3 875 843 218.2 103.8 6.1 328.1 1.97 2.95 4.00 4.43

914 6 16 2.3 902 870 134.3 107.0 6.2 247.6 1.49 2.23 3.02 3.34914 8 16 2.3 898 866 178.7 106.5 6.2 291.5 1.75 2.62 3.56 3.94914 10 16 2.3 894 862 222.9 106.1 6.2 335.2 2.01 3.02 4.09 4.53914 12 16 2.3 890 858 266.9 105.6 6.2 378.7 2.27 3.41 4.62 5.11960 6 16 2.3 948 916 141.2 112.6 6.5 260.3 1.56 2.34 3.18 3.51

S E C T I O N 5 | 31




mm mm mm mm mm mm kg/m kg/m kg/m kg/m Tonne Tonne Tonne Tonne

960 8 16 2.3 944 912 187.8 112.1 6.5 306.4 1.84 2.76 3.74 4.14960 10 16 2.3 940 908 234.3 111.6 6.5 352.4 2.11 3.17 4.30 4.76960 12 16 2.3 936 904 280.5 111.1 6.5 398.2 2.39 3.58 4.86 5.38972 6 16 2.3 960 928 142.9 114 6.6 263.6 1.58 2.37 3.22 3.56972 8 16 2.3 956 924 190.2 113.6 6.6 310.3 1.86 2.79 3.79 4.19972 10 16 2.3 952 920 237.2 113.1 6.6 356.9 2.14 3.21 4.35 4.82972 12 16 2.3 948 916 284.1 112.6 6.6 403.3 2.42 3.63 4.92 5.44

1016 6 16 2.3 1004 972 149.4 119.4 6.9 275.7 1.65 2.48 3.36 3.721016 8 16 2.3 1000 968 198.9 118.9 6.9 324.6 1.95 2.92 3.96 4.381016 10 16 2.3 996 964 248.1 118.4 6.9 373.4 2.24 3.36 4.55 5.041016 12 16 2.3 992 960 297.1 117.9 6.9 421.9 2.53 3.80 5.15 5.701035 6 16 2.3 1023 991 152.3 121.6 7.0 280.9 1.69 2.53 3.43 3.791035 8 16 2.3 1019 987 202.6 121.2 7.0 330.8 1.98 2.98 4.04 4.471035 10 16 2.3 1015 983 252.8 120.7 7.0 380.5 2.28 3.42 4.64 5.141035 12 16 2.3 1011 979 302.7 120.2 7.0 430.0 2.58 3.87 5.25 5.801067 6 16 2.3 1055 1023 157.0 125.5 7.3 289.8 1.74 2.61 3.53 3.911067 8 16 2.3 1051 1019 208.9 125 7.3 341.2 2.05 3.07 4.16 4.611067 10 16 2.3 1047 1015 260.7 124.5 7.3 392.5 2.35 3.53 4.79 5.301067 12 16 2.3 1043 1011 312.2 124.1 7.3 443.5 2.66 3.99 5.41 5.991086 8 16 2.3 1070 1038 212.7 127.3 7.4 347.4 2.08 3.13 4.24 4.691086 10 16 2.3 1066 1034 265.3 126.8 7.4 399.6 2.40 3.60 4.87 5.391086 12 16 2.3 1062 1030 317.8 126.4 7.4 451.6 2.71 4.06 5.51 6.10

1124 8 16 2.3 1108 1076 220.2 131.9 7.7 359.7 2.16 3.24 4.39 4.861124 10 16 2.3 1104 1072 274.7 131.4 7.7 413.8 2.48 3.72 5.05 5.591124 12 16 2.3 1100 1068 329.1 130.9 7.7 467.7 2.81 4.21 5.71 6.311145 8 16 2.3 1129 1097 224.3 134.5 7.8 366.6 2.2 3.30 4.47 4.951145 10 16 2.3 1125 1093 279.9 134.0 7.8 421.7 2.53 3.79 5.14 5.691145 12 16 2.3 1121 1089 335.3 133.5 7.8 476.6 2.86 4.29 5.81 6.43

1200 8 16 2.3 1184 1152 235.2 141.1 8.2 384.4 2.31 3.46 4.69 5.191200 10 16 2.3 1180 1148 293.5 140.6 8.2 442.2 2.65 3.98 5.39 5.971200 12 16 2.3 1176 1144 351.6 140.1 8.2 499.9 3.00 4.50 6.10 6.751219 8 16 2.3 1203 1171 238.9 143.4 8.3 390.6 2.34 3.52 4.76 5.271219 10 16 2.3 1199 1167 298.1 142.9 8.3 449.3 2.70 4.04 5.48 6.071219 12 16 2.3 1195 1163 357.2 142.4 8.3 507.9 3.05 4.57 6.20 6.861283 8 19 2.3 1267 1229 251.5 179.0 8.7 439.3 2.64 3.95 5.36 5.931283 10 19 2.3 1263 1225 313.9 178.5 8.7 501.1 3.01 4.51 6.11 6.761283 12 19 2.3 1259 1221 376.1 177.9 8.7 562.7 3.38 5.06 6.86 7.601290 8 19 2.3 1274 1236 252.9 180.0 8.8 441.7 2.65 3.98 5.39 5.961290 10 19 2.3 1270 1232 315.6 179.5 8.8 503.9 3.02 4.53 6.15 6.801290 12 19 2.3 1266 1228 378.2 178.9 8.8 565.9 3.40 5.09 6.90 7.64

1404 8 19 2.3 1388 1350 275.4 196.4 9.6 481.3 2.89 4.33 5.87 6.50

S E C T I O N 5

Pipe Data

32 | S E C T I O N 5




mm mm mm mm mm mm kg/m kg/m kg/m kg/m Tonne Tonne Tonne Tonne1404 10 19 2.3 1384 1346 343.8 195.8 9.6 549.1 3.29 4.94 6.70 7.411404 12 19 2.3 1380 1342 411.9 195.2 9.6 616.7 3.70 5.55 7.52 8.331416 8 19 2.3 1400 1362 277.8 198.1 9.6 485.5 2.91 4.37 5.92 6.551416 10 19 2.3 1396 1358 346.7 197.5 9.6 553.9 3.32 4.99 6.76 7.481416 12 19 2.3 1392 1354 415.5 197.0 9.6 622.1 3.73 5.60 7.59 8.401422 8 19 2.3 1406 1368 279.0 199.0 9.7 487.6 2.93 4.39 5.95 6.581422 10 19 2.3 1402 1364 348.2 198.4 9.7 556.3 3.34 5.01 6.79 7.511422 12 19 2.3 1398 1360 417.2 197.8 9.7 624.7 3.75 5.62 7.62 8.431440 8 19 2.3 1424 1386 282.5 201.5 9.8 493.9 2.96 4.44 6.02 6.671440 10 19 2.3 1420 1382 352.6 201.0 9.8 563.4 3.38 5.07 6.87 7.611440 12 19 2.3 1416 1378 422.6 200.4 9.8 632.8 3.80 5.69 7.72 8.541451 10 19 2.3 1431 1393 355.4 202.6 9.9 567.8 3.41 5.11 6.93 7.671451 12 19 2.3 1427 1389 425.8 202.0 9.9 637.7 3.83 5.74 7.78 8.611451 16 19 2.3 1419 1381 566.2 200.8 9.9 776.9 4.66 6.99 9.48 10.49

1500 10 19 2.3 1480 1442 367.4 209.6 10.2 587.2 3.52 5.29 7.16 7.931500 12 19 2.3 1476 1438 440.3 209.0 10.2 659.5 3.96 5.94 8.05 8.901500 16 19 2.3 1468 1430 585.5 207.9 10.2 803.6 4.82 7.23 9.80 10.851575 10 19 2.3 1555 1517 385.9 220.3 10.7 617.0 3.70 5.55 7.53 8.331575 12 19 2.3 1551 1513 462.5 219.8 10.7 693.0 4.16 6.24 8.45 9.361575 16 19 2.3 1543 1505 615.1 218.6 10.7 844.5 5.07 7.60 10.30 11.40

1600 10 19 2.3 1580 1542 392.1 223.9 10.9 626.9 3.76 5.64 7.65 8.461600 12 19 2.3 1576 1538 469.9 223.4 10.9 704.2 4.22 6.34 8.59 9.511600 16 19 2.3 1568 1530 625.0 222.2 10.9 858.1 5.15 7.72 10.47 11.581626 10 19 2.3 1606 1568 398.5 227.7 11.1 637.2 3.82 5.74 7.77 8.601626 12 19 2.3 1602 1564 477.6 227.1 11.1 715.8 4.29 6.44 8.73 9.661626 16 19 2.3 1594 1556 635.2 225.9 11.1 872.2 5.23 7.85 10.64 11.78

1750 10 19 2.3 1730 1692 429.1 245.4 11.9 686.4 4.12 6.18 8.37 9.271750 12 19 2.3 1726 1688 514.3 244.9 11.9 771.1 4.63 6.94 9.41 10.411750 16 19 2.3 1718 1680 684.2 243.7 11.9 939.8 5.64 8.46 11.47 12.69

1829 10 19 2.3 1809 1771 448.6 256.8 12.5 717.8 4.31 6.46 8.76 9.691829 12 19 2.3 1805 1767 537.7 256.2 12.5 806.3 4.84 7.26 9.84 10.891829 16 19 2.3 1797 1759 715.3 255.1 12.5 982.8 5.90 8.85 11.99 13.27

1981 10 19 2.3 1961 1923 486.0 278.6 13.5 778.1 4.67 7.00 9.49 10.501981 12 19 2.3 1957 1919 582.7 278.0 13.5 874.2 5.24 7.87 10.66 11.801981 16 19 2.3 1949 1911 775.3 276.9 13.5 1065.7 6.39 9.59 13.00 14.39

2159 10 19 2.3 2139 2101 529.9 304.1 14.7 848.8 5.09 7.64 10.35 11.462159 12 19 2.3 2135 2097 635.3 303.5 14.7 953.6 5.72 8.58 11.63 12.872159 16 19 2.3 2127 2089 845.5 302.4 14.7 1162.6 6.98 10.46 14.18 15.70

S E C T I O N 5 | 33

S E C T I O N 5

Pipe Data

114 4.8 9 1.6 21.5 25.8 0.03 0.1168 4.5 9 1.6 38.0 44.7 -0.04 0.1168 5 9 1.6 39.7 46.4 -0.02 0.1190 4.5 9 1.6 46.3 54.0 -0.08 0.0190 5 9 1.6 48.3 55.9 -0.05 0.1

219 5 9 1.6 60.7 69.7 -0.11 0.0240 5 9 1.6 70.5 80.4 -0.16 0.0257 5 9 1.6 79.0 89.7 -0.20 0.0273 5 9 1.6 87.4 98.7 -0.25 -0.1290 5 12 1.8 96.7 112.4 -0.30 -0.1

305 5 12 1.8 105.3 121.9 -0.35 -0.1324 5 12 1.8 116.8 134.5 -0.42 -0.2324 6 12 1.8 123.5 141.1 -0.35 -0.1337 5 12 1.8 124.9 143.4 -0.47 -0.2337 6 12 1.8 131.9 150.3 -0.39 -0.1356 5 12 1.8 137.3 156.9 -0.55 -0.3356 6 12 1.8 144.7 164.2 -0.47 -0.2

406 5 12 1.8 172.6 195.1 -0.79 -0.4406 6 12 1.8 181.1 203.5 -0.69 -0.4419 5 12 1.8 182.4 205.7 -0.85 -0.5419 6 12 1.8 191.2 214.4 -0.75 -0.4457 5 12 1.8 212.7 238.1 -1.06 -0.7457 6 12 1.8 222.3 247.6 -0.95 -0.6457 8 12 1.8 241.3 266.5 -0.74 -0.4457 10 12 1.8 260.2 285.2 -0.53 -0.2

502 5 12 1.8 251.4 279.5 -1.34 -0.9502 6 12 1.8 262.0 289.9 -1.22 -0.8502 8 12 1.8 283.0 310.7 -0.99 -0.6508 5 12 1.8 256.8 285.2 -1.38 -0.9508 6 12 1.8 267.5 295.8 -1.26 -0.8508 8 12 1.8 288.8 316.9 -1.02 -0.6508 10 12 1.8 309.9 337.8 -0.78 -0.4559 5 12 2 305.1 336.8 -1.74 -1.3559 6 12 2 316.9 348.5 -1.61 -1.1559 8 12 2 340.3 371.7 -1.34 -0.9559 10 12 2 363.6 394.8 -1.08 -0.6

610 5 12 2 357.4 392.1 -2.14 -1.6610 6 12 2 370.3 404.9 -1.99 -1.5610 8 12 2 395.9 430.3 -1.70 -1.2610 10 12 2 421.4 455.6 -1.42 -0.9648 5 12 2 399.0 436.0 -2.46 -1.9648 6 12 2 412.7 449.6 -2.30 -1.8648 8 12 2 440.0 476.6 -2.00 -1.4648 10 12 2 467.1 503.5 -1.69 -1.1660 5 12 2 412.6 450.3 -2.56 -2.0660 6 12 2 426.6 464.1 -2.41 -1.8

660 8 12 2 454.4 491.7 -2.09 -1.5660 10 12 2 482.0 519.2 -1.78 -1.2

700 5 12 2 459.7 499.7 -2.94 -2.3700 6 12 2 474.5 514.4 -2.77 -2.2700 8 12 2 504.0 543.7 -2.44 -1.8700 10 12 2 533.4 572.8 -2.11 -1.5711 5 12 2 473.0 513.7 -3.04 -2.4711 6 12 2 488.1 528.7 -2.87 -2.3711 8 12 2 518.1 558.4 -2.53 -1.9711 10 12 2 547.9 588.1 -2.20 -1.6762 5 12 2 537.5 581.2 -3.56 -2.9762 6 12 2 553.7 597.2 -3.38 -2.7762 8 12 2 585.9 629.2 -3.02 -2.4762 10 12 2 617.9 661.0 -2.66 -2.0

800 5 16 2.3 588.3 648.3 -3.97 -3.1800 6 16 2.3 605.2 665.1 -3.78 -2.9800 8 16 2.3 639.1 698.7 -3.40 -2.5800 10 16 2.3 672.7 732.0 -3.02 -2.1813 5 16 2.3 606.1 667.2 -4.12 -3.2813 6 16 2.3 623.4 684.3 -3.92 -3.0813 8 16 2.3 657.8 718.4 -3.54 -2.6813 10 16 2.3 692.o 752.3 -3.15 -2.2889 5 16 2.3 715.9 782.8 -5.02 -4.0889 6 16 2.3 734.8 801.6 -4.81 -3.8889 8 16 2.3 772.5 839.0 -4.39 -3.4889 10 16 2.3 809.9 876.2 -3.96 -3.0895 5 16 2.3 725.0 792.3 -5.10 -4.1895 6 16 2.3 744.0 811.2 -4.88 -3.9895 8 16 2.3 781.9 848.9 -4.46 -3.4895 10 16 2.3 819.6 886.3 -4.03 -3.0

914 6 16 2.3 773.4 842.1 -5.12 -4.1914 8 16 2.3 812.2 880.6 -4.68 -3.6914 10 16 2.3 850.7 918.9 -4.25 -3.2914 12 16 2.3 889.1 957.0 -3.82 -2.8960 6 16 2.3 847.1 919.4 -5.72 -4.6960 8 16 2.3 887.8 959.8 -5.26 -4.2960 10 16 2.3 928.3 1000.0 -4.80 -3.7960 12 16 2.3 968.7 1040.1 -4.35 -3.3972 6 16 2.3 866.8 940.0 -5.88 -4.8972 8 16 2.3 908.1 981.0 -5.41 -4.3972 10 16 2.3 949.1 1021.8 -4.95 -3.8972 12 16 2.3 990.0 1062.4 -4.49 -3.4

1016 6 16 2.3 941.2 1017.8 -6.49 -5.31016 8 16 2.3 984.4 1060.7 -6.00 -4.81016 10 16 2.3 1027.3 1103.3 -5.52 -4.41016 12 16 2.3 1070.1 1145.8 -5.04 -3.91035 6 16 2.3 974.3 1052.4 -6.76 -5.6

Table 5.2 – SINTAKOTE steel pipe water filled masses and submerged weights of closed and empty pipe

Section Dimensions Water Filled SubmergedMass Weight empty

Steel Shell CML SK Steel SKCL Steel SKCLOD t T ts shell steel shell shell steel shell

+water +watermm mm mm mm kg/m kg/m kN/m kN/m



+water +water mm mm mm mm kg/m kg/m kN/m kN/m

34 | S E C T I O N 5







1035 8 16 2.3 1018.2 1096.0 -6.27 -5.11035 10 16 2.3 1062.0 1139.5 -5.77 -4.61035 12 16 2.3 1105.6 1182.8 -5.28 -4.11067 6 16 2.3 1031.3 1111.8 -7.23 -6.01067 8 16 2.3 1076.6 1156.8 -6.72 -5.51067 10 16 2.3 1121.7 1201.7 -6.22 -5.01067 12 16 2.3 1166.7 1246.4 -5.71 -4.51086 8 16 2.3 1112.0 1193.7 -7.00 -5.81086 10 16 2.3 1157.9 1239.4 -6.49 -5.21086 12 16 2.3 1203.7 1284.9 -5.97 -4.7

1124 8 16 2.3 1184.5 1269.2 -7.58 -6.31124 10 16 2.3 1232.1 1316.5 -7.04 -5.81124 12 16 2.3 1279.5 1363.6 -6.51 -5.21145 8 16 2.3 1225.5 1311.8 -7.90 -6.61145 10 16 2.3 1274 1360.1 -7.36 -6.01145 12 16 2.3 1322.4 1408.1 -6.81 -5.5

1200 8 16 2.3 1336.3 1426.9 -8.79 -7.41200 10 16 2.3 1387.2 1477.4 -8.22 -6.81200 12 16 2.3 1437.9 1527.9 -7.65 -6.31219 8 16 2.3 1375.7 1467.7 -9.11 -7.71219 10 16 2.3 1427.4 1519.1 -8.53 -7.11219 12 16 2.3 1478.9 1570.3 -7.95 -6.61283 8 19 2.3 1512.5 1625.7 -10.22 -8.51283 10 19 2.3 1566.9 1679.8 -9.60 -7.91283 12 19 2.3 1621.2 1733.8 -8.99 -7.31290 8 19 2.3 1527.8 1641.7 -10.34 -8.61290 10 19 2.3 1582.6 1696.1 -9.73 -8.01290 12 19 2.3 1637.2 1750.4 -9.11 -7.4

1404 8 19 2.3 1788.7 1912.9 -12.49 -10.61404 10 19 2.3 1848.4 1972.2 -11.82 -9.91404 12 19 2.3 1907.8 2031.4 -11.15 -9.21416 8 19 2.3 1817.4 1942.7 -12.73 -10.81416 10 19 2.3 1877.5 2002.5 -12.05 -10.11416 12 19 2.3 1937.5 2062.1 -11.37 -9.41422 8 19 2.3 1831.8 1957.6 -12.85 -10.91422 10 19 2.3 1892.2 2017.7 -12.17 -10.21422 12 19 2.3 1952.4 2077.6 -11.49 -9.61440 8 19 2.3 1875.3 2002.8 -13.21 -11.21440 10 19 2.3 1936.5 2063.7 -12.52 -10.61440 12 19 2.3 1997.5 2124.4 -11.83 -9.91451 10 19 2.3 1963.9 2092.0 -12.74 -10.81451 12 19 2.3 2025.4 2153.2 -12.05 -10.11451 16 19 2.3 2147.8 2275.0 -10.67 -8.7

1500 10 19 2.3 2088.0 2220.6 -13.73 -11.71500 12 19 2.3 2151.6 2283.8 -13.02 -11.01500 16 19 2.3 2278.3 2409.9 -11.59 -9.61575 10 19 2.3 2285.3 2424.7 -15.33 -13.21575 12 19 2.3 2352.1 2491.2 -14.58 -12.41575 16 19 2.3 2485.3 2623.6 -13.08 -10.9

1600 10 19 2.3 2353.0 2494.6 -15.88 -13.71600 12 19 2.3 2420.9 2562.2 -15.12 -12.91600 16 19 2.3 2556.2 2696.9 -13.60 -11.41626 10 19 2.3 2424.5 2568.5 -16.46 -14.21626 12 19 2.3 2493.5 2637.2 -15.69 -13.51626 16 19 2.3 2631.1 2774.0 -14.14 -11.9

1750 10 19 2.3 2780.0 2935.2 -19.39 -17.01750 12 19 2.3 2854.4 3009.3 -18.55 -16.21750 16 19 2.3 3002.6 3156.8 -16.89 -14.5

1829 10 19 2.3 3019.1 3181.5 -21.38 -18.91829 12 19 2.3 3096.9 3258.9 -20.50 -18.01829 16 19 2.3 3251.9 3413.2 -18.76 -16.3

1981 10 19 2.3 3506.7 3682.8 -25.47 -22.71981 12 19 2.3 3591.0 3766.8 -24.52 -21.81981 16 19 2.3 3759.1 3934.2 -22.63 -19.9

2159 10 19 2.3 4123.9 4316.1 -30.72 -27.72159 12 19 2.3 4215.8 4407.7 -29.69 -26.72159 16 19 2.3 4399.2 4590.5 -27.62 -24.7

SK, CML abbreviations for SINTAKOTE and cement mortar liningrespectively. Calculations based on:

Masses:

Steel shell: M1 = 0.02466(D-t)t kg/m Cement lining: M2 = 0.00755T(D-2t-T) kg/m SINTAKOTE: M3 = 0.00295Dts kg/mPipe Mass = M1 +M2 +M3 kg/mWater filled bare pipe: Pipe mass +L /4((D-2t)/1000) 2 p kg/m Water filled SKCL pipe: Pipe mass +L /4((D-2t-2T)/1000)2 p kg/m

Weights:

Buoyant weight bare pipe: (Pipe mass-L /4 (D/1000)2 p)g/1000 kN/m Buoyant weight SKCL pipe:(Pipe mass-L /4 ((D+2ts )/1000)2Þ )g/1000 kN/mwhere D = outside diameter of pipe mmt = steel wall thickness mm T = cement mortar lining thickness mm ts = SINTAKOTE® thickness mm p = density of water 1000 kg/m3

g = gravitational acceleration 9.81 m/s

Total mass may carry minor round-off error.

JointingSystems

36

section6

38 | S E C T I O N 6

6.1 GeneralPipes can be supplied with any of the joint configurationsdescribed below. A variety of mechanical jointing systems to suitspecialist requirements can also be supplied.

Jointing systems for fittings can also be specified in theseconfigurations. They are however, subject to geometrical andpractical considerations.

Clients are advised to contact Tyco Water Regional MarketingOffices to discuss detailed requirements.

6.2 SINTAJOINT Advantages of rubber ring joints (RRJ) over welded joints includefaster laying rates, less field plant and maintenance, and speedierbackfilling as this can be done immediately the joint has been laidand checked.

In the case of SINTAJOINT pipe, no joint corrosion protection isnecessary. Therefore minimal excavation at joints is required,allowing trenching to proceed without interruption. See Figure 6.1.

SINTAJOINT is available from 324mm to 1626mm outside diameter

for pipes and fittings. Each joint provides angular deflection up toapproximately 3° depending on diameter. See Graph 6.1.

Due to its insulating properties, the joint is ideal for applicationswhere induced current may be a design consideration, forexample, within power transmission easements.

“Deep entry” SINTAJOINTTo accommodate abnormal angular rotation and axialdisplacements, rubber ring joints can be supplied with a modifiedsocket profile featuring a deeper, wider throat. Design Engineersshould contact one of Tyco Water Regional Marketing Offices todiscuss detailed requirements.

An example of this joint application is in mine subsidence areaswhere ground strain can be high, typically in the range 3 to 7 mm/m.

Laying SINTAJOINT pipeRecommended practices for laying rubber ring joint steel pipes areprovided in the SINTAKOTE Steel Pipeline System “Handling andInstallation Reference Manual”.

Design engineers in particular should be familiar with thesepractices for consideration in design.

Figure 6.1 - SINTAJOINT rubber ring joint

Figure 6.2 - Spherical slip-in joint

Figure 6.3 - Ball and socket joint

test point

Figure 6.4 - Butt joint with collar Figure 6.5 - Plain butt joint

S E C T I O N 6 | 39

6.3 Welded jointsWelded joints ensure 100% structural integrity. Where an internaland external weld is used they can also permit a pneumatic test ofthe weld integrity in the field during construction. Complete internaland external circumferential welds are necessary however, and adrilled and tapped hole accessing the air space between thewelds must also be provided for an air nozzle to be attached. The weld is then daubed with a soap solution and the annuluspressurised to around 100 kPa. The welds are then examined forbubbles of escaping air and rectified if necessary. For largepipelines this test can assure integrity as construction progresseseliminating the time and cost of a major hydrostatic field test. See Figure 6.3 for a typical arrangement.

The integrity of spherical slip-in and ball and socket welded joints may be assessed by this test. See our separate Handling and Installation manual for further details.

Spherical slip-in joint (SSJ)This pipe joint is available in sizes 168 to 1422mm OD, in wallthicknesses up to 12mm with deflections up to 3° available in thesmaller diameters. Deflections are based on proprietary calculationsand can be obtained from your nearest Tyco Water RegionalMarketing Office. Field welding may be carried out internally as well as externally in pipes large enough to provide adequateinternal access. Generally, pipes above 813mm OD will allow this. See Figure 6.2.

Ball and socket joint (B&S)This pipe joint is available in sizes G806mm OD and allows 3°deflection per joint prior to welding. See Figure 6.3.

Butt joint with collarSquare end preparation is required. Pipes and collar are easy to alignand the configuration is often used in closing lengths. See Figure 6.4.

It can also be used for smaller diameter pipes to eliminate internalgaps in cement mortar lining.

Butt joint The plain butt joint may be satisfactorily welded from one sideusing a root fill and hot-pass method, if required, provided that the joint is NDT inspected in accordance with AS 1554. Note that pipe ends must be bevelled to achieve a reasonableweld, and the ends of the cement mortar lining must have been prepared as indicated.

This method is particularly useful for small diameter pipes whereinternal reinstatement of the cement mortar lining cannot beperformed by hand. See Figure 6.5. Graph 6.1 - SINTAJOINT RRJ angular deflections

S E C T I O N 6

Jointing Systems

1700

1600

1500

1400

1300

1200

1100

1000

900

800

700

600

500

400

300

200

3.5° 3° 2.5° 2° 1.5° 1° 0.5°

Tem

pora

ry c

onst

ruct

ion

defle

ctio

n

Per

man

ent d

efle

ctio

n

OD

. Out

side

dia

met

er in

mill

imet

res

£ Deflection angle in degrees

£

Estimated Torque

Lightly Oiled Well

Galvanised, or Lubricated

Flange Pipe No. Bolt Bolt Well Lubricated Galvanised

DN OD of Size Tension Stainless Steel Steel

Bolts Studs or Bolts Studs or Bolts

k = 0.22 k = 0.15

mm kN Nm Nm

100 114 4 M16 20 75 50

150 168 8 M16 20 75 50

200 178, 190, 219 8 M16 20 75 50

225 235, 240 8 M16 20 75 50

250 257, 273 8 M20 30 135 90

300 290, 305, 324 12 M20 30 135 90

350 337, 356 12 M24 48 255 175

375 368 12 M24 48 255 175

400 406, 419 12 M24 48 255 175

450 457 12 M24 48 255 175

500 502, 508, 559 16 M24 48 255 175

600 610, 648, 660 16 M27 68 405 280

40 | S E C T I O N 6

6.4 Flanged jointsFlanged joints are completely rigid and should not be used forapplications where movement of the pipeline is expected, unlessspecial provision is made to accommodate it by, for example, theinclusion of expansion joints.

Flanged joints are used mainly for above ground applications, e.g. pumping stations, water and sewage treatment plants and forindustrial pipework. They are also used to facilitate the installation

and removal of valves in SINTAJOINT and welded pipelines and forvalve bypass arrangements.

For assembly of flanged joints no field welding or other specialequipment is required. Flange dimensions are normally inaccordance with AS 4087 and are currently supplied in Class 16,Class 21 or Class 35.

For access covers and other blank flange joints Tyco Waterrecommends the use of o-ring type gaskets because of their lowrequirement for assembly stress and trouble free operation. O-ringflanged joints have these same advantages in other flanged jointsituations but it must be remembered that the use of o-ring typeflanges requires full knowledge of all of the mating components toavoid a joint situation with two o-ring groove ends joining eachother. The correct matching is shown in Figure 6.7.

Where it is not possible or desirable to use o-ring type flanges,Tyco Water recommends the use of raised face steel flanges. See Figure 6.6. The use of flat-faced steel flanges is not preferredexcept when the mating flange is cast iron. This situation mayoccur at a pump housing, but current practice is for most pipelinecomponents to be manufactured in wholly steel or ductile iron.

Maximum Maximum Gasket Operating Pressure, Temperature, Composition

MPa °C1.6 50 Solid EPDM Rubber

3mm thick

3.5 80 Composite fibre 1.5mm thick

TEADIT NA1000C6327 or equivalent)

Table 6.1 Recommended gasket composition for transportationof general domestic liquids including brine and sewage

TABLE 6.2 - Recommended Bolt Torques for Steel Flanges Class 16 with EPDM Solid Rubber GasketsGasket - Full Face 3mm EPDM Solid Rubber for raised face flanges

- Ring type 3mm EPDM Solid Rubber for flat face flanges

Grade 4.6 Galvanised Steel Bolts & Nuts, or Stainless steel Bolts & Nuts Property Class 50 (min)

Estimated Torque

Lightly Oiled Well





k = 0.22 k = 0.15

mm kN Nm Nm

100 114 8 M16 40 145 100

150 168, 178 12 M20 44 195 135

200 190, 219 12 M20 75 330 225

225 235, 240, 257 12 M24 80 425 290

250 257, 273, 290 12 M24 86 455 310

300 305, 324, 337 16 M24 86 455 310

350 356, 368 16 M27 100 595 405

375 406, 419 16 M27 100 595 405

400 419 20 M27 100 595 405

450 457, 502, 508 20 M30 112 740 505

500 559 24 M30 112 740 505

600 610, 648, 660 24 M33 150 1090 745

700 700, 711, 762 24 M33 160 1165 795

750 800, 813 28 M33 160 1165 795

800 889 28 M33 160 1165 795

900 914, 959, 965, 972 32 M36 190 1505 1030

1000 1016, 1035, 1067, 1086 36 M36 190 1505 1030

1200 1124, 1145, 1200, 1219, 40 M39 310 2660 1815

1238, 1290

S E C T I O N 6 | 41

Experience has shown that flat-faced flanges are generally moresusceptible to sealing problems and successful sealing is heavilydependent upon assembly technique.Where the required flange sizes are larger than DN 1200 or areoutside the normal pressure rating, special flanges must bedesigned. In this situation o-ring type flanges are recommended asbeing the best option for medium to high pressure situations.

GasketsGaskets may be either elastomeric or compressed fibre type.Elastomeric gaskets are only recommended for the Class 16flanges. Compressed fibre gaskets are recommended for Class 21and Class 35 flanges. Compressed fibre gaskets can also be usedwith Class 16 flanges but will require the use of high strength boltsbecause of the higher initial compression necessary.

Table 6.1 details the recommended type of gasket and bolt to beused for various classes of raised face steel flanges. Generally fullface gaskets (that incorporate holes for the flange bolts) can beused with raised face flanges as only the raised face area insidethe bolt holes is clamped. The full face gasket enables betterlocation of the gasket compared to a ring type gasket. (If rigidcompressed fibre type gaskets are used the use of ring typegaskets is normal)

For other liquids, temperatures or pressures contact a Tyco WaterRegional Marketing Office.

Flange bolts and assembly torqueBolting used on flanges is usually galvanised steel or stainless

TABLE 6.3 - Recommended Bolt Torques for Raised Face Steel Flanges Class 21 with Compressed Fibre GasketsGasket - Full Face 1.5mm TEADIT NA1000 Compressed Fibre.Grade 8.8 Galvanised Steel Studs and Nuts, or Stainless Steel Studs and Nuts, Property class 70

TABLE 6.4 - Recommended Bolt Torques for O-Ring Steel Flanges Class 35

Gasket - Elastomeric O-Ring

Grade 8.8 Galvanised Steel Studs & Nuts, or Stainless steel Studs & Nuts Property Class 70

42 | S E C T I O N 6

Estimated Torque

Lightly Oiled Well





k = 0.22 k = 0.15

mm kN Nm Nm

300 290, 305, 324, 337 16 M24 35 185 130

350 337, 356, 368 16 M27 45 270 185

375 368, 406, 419 16 M27 45 270 185

400 406, 419 20 M27 45 270 185

450 457, 502, 508 20 M30 56 370 255

500 502, 508, 559 24 M30 56 370 255

600 559, 610, 648, 660 24 M33 69 505 345

700 660, 700, 711 24 M33 69 505 345

750 762, 800, 813 28 M33 69 505 345

800 762, 800, 813 28 M33 69 505 345

900 889, 914, 959, 965, 972 32 M36 81 645 440

1000 972, 1016, 1035, 1067, 36 M36 81 645 440

1086

1200 1124, 1145, 1200, 1219, 40 M39 97 835 570

1238, 1290

steel. Commercial grade bolts are used with the Class 16 flangesand rubber gaskets while high strength studs and nuts are requiredfor use with compressed fibre gaskets.

Poor assembly technique is by far the greatest single cause offlange joint failure and use of the correct technique and selection ofthe suitable bolt torque is vital. Tables 6.2 to 6.4 may be used as aguide for determining the final torque setting for any flange withinthe specified range.

Special Note: The use of stainless steel bolting has becomecommon on flange joints. While stainless steel may provide anadditional benefit from a corrosion protection viewpoint in certain

circumstances it also presents certain hazards. Firstly the friction

factors on stainless steel exceed those of galvanized steel by 30%

to 60%, requiring greater assembly torque. Secondly stainless steel

1. 'Lightly oiled' refers to the application of a good quality lubricating oil and is the usual as received condition of fasteners.

2. 'Well lubricated' refers to the application of molybdenum disulphide or Koprkote grease.

3. The estimated torques provided in the table are based on the friction factor (k) indicated.

Where other factors apply, alternative torques should be calculated.

4. Required bolt tensions and estimated torques have been assumed using established engineering principles.

However, variation in installation procedures may result in different requirements.

S E C T I O N 6 | 43

Fig 6.7 Matched o-ring type flangesFig 6.6 Raised face type flanges

14

10

62 15

3

134

8

1612

9

15

7

11

Figure 6.8 Star pattern tightening sequence

has a tendency to gall (locking on the threads) and thereby nottransmit the applied torque into bolt tension. Galling is notprevented by using only slightly differing grades of stainless steele.g. 304 and 316 for the nut and bolt. Good lubrication of stainlesssteel is vital to the successful flange joint installation. Tyco Waterrecommends the liberal application of Koprkote grease to thethreads and between the nut and washer.

Jointing instructions for flanged joints1.Use a scraper or wire brush to thoroughly clean the flange facesto be jointed, ensuring there is no dirt, particles or foreign matter,protrusions or coating build-up on the mating surfaces.

2. Ensure that the mating threads of all nuts and bolts are cleanand in good condition.

3. Evenly apply a suitable lubricant (e.g. molybdenum disulphide) toall mating threads, including the nut load bearing face and washer.

4. Align the flanges to be joined and ensure that the componentsare satisfactorily supported to avoid bending stress on the flangedjoint during and after assembly.

5. Insert four bolts in locations 1 to 4 as indicated in Figure 6.8 andposition the insertion gasket on the bolts, taking care not todamage the gasket surface.

6. Offer the adjoining flange to the bolts, taking care to maintainsupport and alignment of the components.

7. Tighten nuts to finger tight and check alignment of flange facesand gasket.

8. Insert the remaining bolts and tighten nuts to finger tight.

9. Estimate the required bolt torque considering bolt type andallowable tension, flange type and rating, gasket material andmax/min compression, and the pipeline’s maximum pressure(operating/test pressure). Refer to tables 6.2 to 6.4 for recommendedtorque values. Information on the required bolt torque for other flange

types and gasket material can be obtained from Tyco Water.

10. Tighten nuts to 20% of estimated torque using the star pattern;see Figure 6.8.

11. Tighten to 50% of estimated torque using the same tighteningsequence.



14. Repeat the tightening procedure on all nuts until little or nomovement can be achieved on each nut. (particularly important onelastomeric gaskets)

• Bolt tensions need to counter the force due to expected internalpressure and to provide an adequate sealing stress without exceedingthe maximum allowable gasket stress at the time of installation.

• The application of excessive torque at the time of installation mayoverstress the gasket causing crushing or extrusion, which canlead to leakage at operating pressures.

• The surface conditions of the threads as a result of rust, plating,coating and lubrication are the predominant factors influencing thetorque / tension relationship. However, there are many others includingthread fit, surface texture and the speed and continuity of tightening.

• The flange faces are assumed to have a surface roughness of Ra = 10 -12.5 µm.

• A torque wrench is most commonly utilised to achieve therequired bolt tension, however in critical applications an hydraulictensioner should be used.

S E C T I O N 6

Jointing Systems

Fittings

44

section7

46 | S E C T I O N 7

7.1 Preferred sizes, dimensions andtypical configurationsFittings are normally fabricated from pipe. Pipe wall, coating andlining thicknesses, and outside diameters are therefore inaccordance with Table 5.1.

Table 7.1, Figure 7.1 and Figure 7.2 depict a range of cost effectivefitting configurations manufactured by Tyco Water. Whilst thesesizes are preferred, Tyco Water can make any size that is required.

7.2 SINTAJOINT fittingsSINTAJOINT fittings are available in sizes 324mm OD to 1626mmOD and allow construction of a complete rubber ring joint pipelinesystem. This eliminates welding entirely.In particular, no joint reinstatement or field joint overwrap of anykind is required and over excavation of the trench at joints forwrapping access is unnecessary.

Tapers, tees and air valves or scour off-takes are also available.

7.3 Welded joint SINTAKOTE fittings Most welded joint fittings are available with SINTAKOTE, fusionbonded polyethylene coating.

Typical fitting dimensions are shown in Table 7.1. Changes inpipeline direction can be achieved by the appropriate combinationof joint deflection and specified bends.

Figure 7.1 Typical Fittings

Tee Angled Branch Y– Piece

Q

d

PM N

30° min.

USS

d

Mitred Bends

Figure 7.2 Typical Reducers

Concentric Reducer

150mm ~4.5 x (D1 – D2) 150mm

150mm ~4.5 x (D1 – D2) 150mm

D1

D1

Eccentric Reducer

D2

D2

Diameter Mitred Bends Tee Angle Branch Y - Piece

< 22.5o = 22.5o to 45o = 45o to 90o (30o minimum) (45o)

d mm M mm N mm R1 mm P mm R2 mm Q mm S mm U mm S mm U mm

200 300 360 500 650 500 325 250 850 250 825

250 375 360 500 650 500 350 250 1000 250 890

300 375 380 550 700 550 375 250 1100 250 950

350 450 420 650 800 650 400 250 1200 250 1025

400 450 465 750 900 750 425 250 1300 250 1100

450 450 485 800 950 800 450 250 1400 250 1150

500 450 525 900 1050 900 475 300 1500 300 1225

550 525 565 1000 1150 1000 525 300 1650 300 1300

600 525 610 1100 1250 1100 575 300 1800 300 1350

650 525 650 1200 1350 1200 625 300 1900 300 1425

700 525 690 1300 1450 1300 675 300 2000 300 1500

750 600 710 1350 1500 1350 750 300 2100 300 1550

800 600 755 1450 1600 1450 775 300 2200 300 1600

900 600 815 1600 1750 1600 825 350 2400 400 1750

1000 750 900 1800 1950 1800 875 400 2600 400 1850

1100 750 980 2000 2150 2000 925 400 2800 400 2000

1200 825 1065 2200 2350 2200 975 500 3000 500 2150

1300 825 1105 2300 2450 2300 1025 500 3200 500 2275

1400 825 1190 2500 2650 2500 1075 500 3400 500 2400

1500 825 1270 2700 2850 2700 1125 600 3600 600 2550

1600 900 1355 2900 3050 2900 1175 600 3800 600 2675

1700 900 1395 3000 3150 3000 1225 600 4000 600 2800

1800 900 1500 3250 3400 3250 1275 600 4200 600 2950

1900 900 1560 3400 3550 3400 1325 600 4400 600 3050

2000 900 1645 3600 3750 3600 1375 600 4600 600 3200

2100 900 1725 3800 3950 3800 1425 600 4800 600 3325

S E C T I O N 7 | 47

7.4 Special fittingsTyco Water can fabricate and supply special fittings in addition tothose indicated to suit your specific needs, for example: expansionjoints, ring girders and support assemblies and complex fittings likebifurcations and trifurcations.

Technical assistance is readily available on request in connection with any problems relating to pipe specials. Although not illustrated we can also supply plate flanges to suit various specifications.

Table 7.1 Fitting configurations manufactured by Tyco Water.Note: Mitred bend radii designed to restrict stress concentration at inside leg to max of 1.25 times hoop stress in pipe.

S E C T I O N 7

Fittings

Design – GeneralConsiderations

48

section8

50 | S E C T I O N 8

8.1 Safe designLong-term safety of buried pipelines will be achieved if, at the designstage, the following are known with a fair degree of confidence:

• the properties of the pipe material and of the pipe itself, asspecified by standards and warranted by the manufacturer.

• the loads that the pipeline will be subjected to, as determined byadequate design methods, based on accepted theories andexperimental evidence.

• the environment in which the pipeline will operate including itschemical nature and temperature.

However, 100% confidence in accessing the conditions above is unachievable at reasonable cost. The Engineer thus uses a design safety factor in matching the pipe minimum strength to the expected loads.

The real safety factor of the buried pipeline is usually larger than thedesign safety factor because:

(i) the pipe minimum characteristics are generally exceeded, and

(ii) the design method includes criteria which are conservative.

Greater confidence in the design and its performance is thus justifiedknowing the formal factors of safety are associated with minimumproduct performance criteria and conservative design procedures.

8.2 Check list for pipeline designIn order to establish the diameter and wall thickness of a pipeline itis necessary to consider a number of interrelated factors.

In some cases the operating pressure and flow requirements willdetermine these dimensions. On other occasions such factors asexternal loading, soil stability and type, conditions of support(above ground, bridge crossings, river crossings) as well as axialforces may influence the calculations and necessitate some local oroverall increase in wall thickness.

In certain situations the design operating criteria alone may result in adiameter to wall thickness ratio considered too high for mechanicalstability of the pipe during manufacture, handling and installation.

DESIGN SUPPLY CONSTRUCT OPERATE & MAINTAIN

Location Compaction Availability Handling Water quality

Route Jointing Lead time Storage Operating costs

Topography Fittings Product standards Bedding Cleaning

Geology Air valves Quality AS9001/2 Jointing Air Valves

Flow requirements Isolating valves Delivery period Backfill Repairs

Future boosting Scour tees Transport Compaction Spares

Diameter Anchor blocks Handling Field test Availability

Velocity Product standards Storage Repairs Cut-ins/branches

Headloss Quality AS9001/2 Seasonality Temperature Exposure

Pressure External corrosion UV radiation Anchor blocks

Water hammer Internal corrosion Seasonality Reinstatement

External loads Seasonality Economics

Cover Temperature Finance

Traffic UV radiation Net present value

Water table Economics

Bedding Finance

Backfill Net present value

Table 8.1- Checklist of typical design factors

S E C T I O N 8 | 51

The additional wall thickness specified to overcome this representsa major benefit should a need arise to increase pipeline pressureand boost flow some time after the line has been in service.

Integration of the numerous design principles is complicated andrequires a systematic approach to optimise the design in terms ofperformance and cost effectiveness.

A comprehensive design will consider factors of pipeline component

supply, construction, operation and maintenance and account fortheir effect on the viability, benefits and cost of the project.

Table 8.1 is a checklist of some factors to consider for a typicalpipeline.

8.3 General design procedure for buriedpipelines

1) Define pipeline

Route

Length

Profile

Jointing type

Several solutions are normally

possible and alternatives will need to beassessed financially or

economically.

Consider demand growth, staging,boosting.

Pipeline jointing system RRJ or

welded may affect profile, design

flexibility and pressure limitation.

Section 8.2 and Table 8.1

Section 8.3

Chapter 6 and Table 5.1

H Y D R A U L I C D E S I G N O F P I P E L I N E SACTION COMMENTS DESIGN MANUAL REFERENCES

2) Trial HGL

Identify boundary and

intermediate HGL limits of

operation.

Trial possible HGL'S

Normally set by defined existing limitations:free water surface levels, terrain etc.Ignore fittings losses.Flow velocities generally between 1 and 2m/s,Headlosses generally 2 to 7 m/km.

3) Solve for

diameter, given flow and headloss

or flow, given headloss and

diameter or headloss, given flow

and diameter.

Identify optimum alternative.

For pumped systems match "systemcurve" with pump characteristics andoptimum duty point.

Chapter 10 - Section 10.1, 10.2.

Graph 10.1,

examples Section 10.5.

4) Define maximum pressure

Add fittings and appurtenance

headlosses.

Static head

Pump shut off head

PRV setting

Consider a range of operating conditions.

Check HGL always above pipe level.

Fittings losses see Section 10.4 and Table 10.1.

Appurtenances Section 16.2.

Recommended maximum internalpressures see Table 9.3

S E C T I O N 8

Design — General Considerations

52 | S E C T I O N 8

5) Estimate steel wall thickness

t = PD/2f

Check D/t < 165 for CML pipe,increase it if not,

Maximum static working stress [f = 0.72MYS]

D/t <165 for manufacturing, lining andhandling considerations.

Chapter 9

6) Select available pipe

Closest bore

Closest steel wall thickness

Check availability and lead time ofselection with your nearest Tyco Water Regional Marketing Office.

Table 5.1

7) Check water hammer

P = 2ft/D ort = PD/2f

From simple checks to full computermodelling.Increase t, reselect pipe if necessary.

Allowable working pressure.

Allowable wall stress[f = 0.90 MYS]

Simple water hammer check vs fullanalysis. Increasing wall thicknessincreases surge peaks - check designchanges

Table 9.3

Section 9.2

Section 11

8) Refine HGL and hammer analyses

Finalise hydraulic appurtenancedesign, fittings etc.

Check final HGL and hammer analyses

Detailed design of selected size. See texts and references

Listed in Appendix D.

9) Define structural deflection limits To ensure joint integrity a 2% ringdeflection limit is recommended for RRJpipelines.

To ensure lining integrity a 3% ringdeflection limit is recommended for weldedpipelines

Section 13.5

Figure 9.1

10) Determine maximum load (Pmax) fordeflection limit.

Select a trial installation design trenchwidth and depth,

Section 16.1, 16.2

Table 13.3

S T R U C T U R A L D E S I G N O F P I P E L I N E SACTION COMMENTS DESIGN MANUAL REFERENCES

11) Calculate design load (P)

P < Pmax ?

Consider worst load case for deflection.

Usually (dead + live load) pipe emptyduring construction.

If P > Pmax, increase pipe teq and/or soilmodulus E’.

Section 13.2

S E C T I O N 8 | 53

8.4 Economic appraisalAs well as the physical aspects of pipeline design a combination ofinterrelated economic decisions must be taken, including pipelinediameter selection and choice of pipeline material. The objective isusually to minimise total cost (initial cost, operation and maintenancecosts) by selecting the alternative that results in the least life-cycle cost.

Factors influencing the economic decision include:• Initial cost of pipeline components• Initial installation costs• Cost to increase capacity in future

• Maintenance costs• Cost of pipeline replacement• Initial cost of pumping stations• Annual power costs• Projected life of pipeline

DCF methodsIt is generally considered that discounted cash flow (DCF)methods should be used in order to provide a rational basis forevaluating and ranking investment options.These DCF methods take account of both the magnitude and timing

12) Determine maximum allowablebuckling pressure (qmax) and criticalbuckling pressure.

Consider buried and exposed ring bucklingstability.

Section 9.4.

Section 13.7.

13) Calculate design buckling pressure (q)

q F qmax ?

Consider worst load case for buckling.

Usually (dead load + vacuum) or

(dead + live load).

If q > qmax increase pipe teq and/or

soil modulus E’.

Section 13.7.

14) Structural design complete

Specify pipeline.

Specify pipe dimensions andinstallation design.

15) Grades Consider air entrapment. Section 8.6

17) Anchorage of pipelines Anchorage should be considered forall rubber ring jointed pipelines.

Include field test pressure anchorageperformance.

Section 12.

16) Valves Consider requirements for:

Air valves

Scour valves

Isolating valves

Section 8.7

18) Cathodic protection Secondary protection Section 3.2

O P E R AT I O N A L C O N S I D E R AT I O N SACTION COMMENTS DESIGN MANUAL REFERENCES

S E C T I O N 8


54 | S E C T I O N 8

years % Interest Rate or Discount Rate

n 1 2 3 4 5 6 7

5 4.8534 4.7135 4.5797 4.4518 4.3295 4.2124 4.1002

10 9.4713 8.9826 8.5302 8.1109 7.7217 7.3601 7.0236

15 13.8651 12.8493 11.9379 11.1184 10.3797 9.7122 9.1079

20 18.0456 16.3514 14.8775 13.5903 12.4622 11.4699 10.5940

25 22.0232 19.5235 17.4131 15.6221 14.0939 12.7834 11.6536

30 25.8077 22.3965 19.6004 17.2920 15.3725 13.7648 12.4090

35 29.4086 24.9986 21.4872 18.6646 16.3742 14.4982 12.9477

40 32.8347 27.3555 23.1148 19.7928 17.1591 15.0463 13.3317

45 36.0945 29.4902 24.5187 20.7200 17.7741 15.4558 13.6055

50 39.1961 31.4236 25.7298 21.4822 18.2559 15.7619 13.8007

55 42.1472 33.1748 26.7744 22.1086 18.6335 15.9905 13.9399

60 44.9550 34.7609 27.6756 22.6235 18.9293 16.1614 14.0392

80 54.8882 39.7445 30.2008 23.9154 19.5965 16.5091 14.2220

100 63.0289 43.0984 31.5989 24.5050 19.8479 16.6175 14.2693

years % Interest Rate or Discount Rate

n 1 2 3 4 5 6 7

5 0.95147 0.90573 0.86261 0.82193 0.78353 0.74726 0.71299

10 0.90529 0.82035 0.74409 0.67556 0.61391 0.55839 0.50835

15 0.86135 0.74301 0.64186 0.55526 0.48102 0.41727 0.36245

20 0.81954 0.67297 0.55368 0.45639 0.37689 0.31180 0.25842

25 0.77977 0.60953 0.47761 0.37512 0.29530 0.23300 0.18425

30 0.74192 0.55207 0.41199 0.30832 0.23138 0.17411 0.13137

35 0.70591 0.50003 0.35538 0.25342 0.18129 0.13011 0.09366

40 0.67165 0.45289 0.30656 0.20829 0.14205 0.09722 0.06678

45 0.63905 0.41020 0.26444 0.17120 0.11130 0.07265 0.04761

50 0.60804 0.37153 0.22811 0.14071 0.08720 0.05429 0.03395

55 0.57853 0.33650 0.19677 0.11566 0.06833 0.04057 0.02420

60 0.55045 0.30478 0.16973 0.09506 0.05354 0.03031 0.01726

80 0.45112 0.20511 0.09398 0.04338 0.02018 0.00945 0.00446

100 0.36971 0.13803 0.05203 0.01980 0.00760 0.00295 0.00115

Table 8.3 - Present value of an annuity

Table 8.2 - Present value of a single sum

S E C T I O N 8 | 55

of expected cash costs each year in the life of a project. Cash flowsare discounted at a predetermined real discount rate. The resultingpresent worth of the DCF is the basis for comparing alternatives.

For diameter selection total present value of alternatives can beobtained by adding present capital cost to net present value of futurecosts (eg. annual pumping costs, maintenance, scheme replacement).

Table 8.2 enables the calculation of present values of future capital cost:Factors for calculating present value of a single sum.The present value of $1 in n years time, when discounted atinterest rate ri per annum is:(1+ri ) –n where ri = % interest rate/100

Table 8.3 enables the calculation of present values of annualoperating costs.

Real discount rateThe discount rate used has a major effect on the result of presentvalue calculations, and various rates should be used to provide asensitivity analysis on any project.

(See Table 8.3 - Present value of an annuity)

The present value of $1 per annum for n years when discounted atinterest rate ri per annum is:(1-(1+ri)

-n)/ri ri = % interest rate/100

The amount per annum to redeem a loan of $1 at the end of n yearsand provide interest on the outstanding balance at ri per annum canbe determined from the reciprocals of values in this table.

8.5 Properties of steelSteel water pipe manufactured to AS 1579 is normally manufacturedfrom AS 1594 analysis grade HA1016 & HXA1016 steel coil or flatplate to AS 3678 Grade 250. HA1016 & HXA1016 is supplied by thesteel maker with prescribed chemical analysis limits.

HA1016 & HXA1016 mechanical property limits are not guaranteedby the steel maker, but the statistical distributions associated withthe chemical analysis limits are accurately known from historicaldata. Minimum mechanical property values associated with theselimits have been identified and are included in Table 8.4.

Yield strength performance of the steel to make the pipe is assuredby the hydrostatic test of each pipe after manufacture to 90% MYS(minimum yield strength).

The hydrostatic factory test not only proves minimum steel strengthbut also tests the welding and ultimate fitness for purpose.

Steel to other grades and specifications can be supplied if required.See Section 2.1.

For pipe that is not hydrostatically tested in accordance with AS 1579, the design pressure rating of the pipe must be includedin the design. The wall thickness of pipes that are non-hydrostatically tested shall be no less than 8.0mm. If pipes arenot hydrostatically pressure tested, then all welds shall be 100%non-destructively tested in accordance with AS 1554.1, categorySP, and the maximum hoop stress at the rated pressure shall notexceed 0.50 of the specified minimum yield stress of the steel.

Other typical properties include:• Modulus of elasticity: Est = 207000 MPa• Linear coefficient of thermal expansion:

| = 12 x 10-6 mm/mm/°C• Thermal conductivity: k = 47 W/(m °C)• Density: ª = 7850 kg/m3

• Melting temperature: approx 1520 °C• Poisson ratio: § = 0.27

8.6 Air entrapmentIn a water supply pipeline air must be evacuated in order for themain to be filled and function properly.

Air can be brought into the pipeline under pressure should pumpglands or inlet pipe not be properly sealed.

Dissolved air can be liberated at points where the pressure is lower,and move along the pipeline to accumulate at high points.

The pipeline profile should be designed to facilitate expulsion of airat predetermined high points where a release valve can be located.

Entrained air in a pipeline can give rise to:• Drop in flow rate through a reduction in bore area caused by

Thickness Min. yield strength Min. tensile strength Product Standard Gradet mm MPa MPa

t F 6 300 410 AS1594 HA1016

6 < t F 8 300 410 AS1594 HXA1016

8 < t F 12.7 250 410 AS1594 HXA1016

t > 12.7 250 410 AS3678 250

Table 8.4 - Steel strength

S E C T I O N 8


trapped air pockets at line peaks, changes of slope, blind ends orlow pressure zones near fittings.• Increase in energy requirement in pumped mains. A 1% byvolume of air bubbles can lower pump efficiency by 15%.• Water hammer due to inflow of water into the collapsing volumeof a large air pocket.• 'White water' turbidity due to entrained microscopic bubbles.Although the air clears slowly, consumer complaints may result onaesthetic grounds and the resulting interference with industrialprocesses such as filtration.

Some suggestions to assist in the expulsion of air:• If possible give the pipeline a uniform gradient of at least 2 to 3in 1000 to help air rise.• Where practicable avoid too many changes of slope.• If the pipeline has several high points, minimum gradient shouldbe 2 to 3 in 1000 in rising sections and 4 to 6 in 1000 indescending sections.• On level ground pipeline should be laid with artificial high points sincea level pipeline may develop high points as a result of earth settlement.

8.7 Valves

Air valvesAir valves and anti-vacuum valves should be located at the highpoints on the pipeline to release accumulated air, or to allow air toenter should a partial vacuum occur.

Supplementary air valves may be installed before stop valves andnon-return valves where these are liable to be closed duringdraining and refilling of the pipeline. Consideration should be givento the placement of air valves at intervals of 500m to 1000m overlong ascending lengths of pipeline.

Scour valvesScour valves are necessary to allow sediment to be flushed outand to enable the pipeline to be drained for maintenance andrepair work, particularly on valve equipment. They should belocated on invert scour tees at low points and between isolatingvalves on the pipeline. The location of these valves is ofteninfluenced by the need to dispose of the scour water.

Their size depends on the maximum time the pipeline may be outof service, and the maximum disposal flow available, for examplesewer lines.

If sewers are used for disposal, measures should be taken toensure backflow is prevented.

In parallel lines scour valves can be interconnected to allow bottomcharging of the empty line. This minimises air entrainment.

Isolating valvesIsolating or sectioning valves are used to isolate sections of apipeline in an emergency or for maintenance.

They should be located at high or low points. High points aregenerally more accessible, however low point located valves allowshorter pipeline lengths to be drained.

In parallel lines with twin isolating valves, cross connections fromupstream of the valve on one line to downstream of the valve onthe other allow greater flexibility in operation.

On large pipelines, isolating valves may be actuator driven to closeon detection of abnormally high flow rates caused by accidental linerupture. Detection devices include pitot-static tubes, orifice platesor venturi meters.

8.8 Determination of wall thicknessTo establish the appropriate steel wall thickness the followingfactors must be taken into account.

Internal pressure, including consideration for water hammer (surge pressure).

External pressure, including earth fill pressure, atmospheric andhydraulic pressure, trench loading pressure and where applicableinternal part or full vacuum.

Structural loading, for example beam loading stresses in aboveground pipes and saddle stresses at supports.

Practical requirements, such as pipe rigidity during manufacturehandling and laying.

8.9 Axial loadsA welded pipeline is axially restrained. Internal pressure will thereforecause longitudinal tension due to Poisson's effect. Thermal expansionor contraction can also cause axial loads. Pipe "beam bending" due touneven bedding, differential settlement or soil subsidence is anothercause of axial loading.

At pipe bends, forces are generated by the internal pressure anddirection changes if velocity and volumes are significant. If notdirectly absorbed in thrust blocks these become axial loads actingon the pipeline. High hydrostatic loads may arise at valves or blankends and if not restrained in thrust blocks may cause additionallongitudinal stresses in the pipeline.

All structures securing the pipeline must be adequately designed tocarry these loads in service and also during the hydrostatic testingof the pipeline when high temporary loads may be created by theincreased test head.

S E C T I O N 8


S E C T I O N 8 | 57

StructuralPropertiesof Pipe

58

section9

60 | S E C T I O N 9

9.1 StandardsA list of applicable Australian Standards used in steel pipe designand specification is included in Section 2.

9.2 Recommended maximum internalpressuresAll pipe manufactured to AS 1579 is hydrostatically proof tested inthe factory to 90% MYS. Table 9.3 lists recommended maximumrated pressures for rubber ring and welded joint pipes.

Pressure formulaThe Barlow formulae given below were used to calculate themaximum test and maximum working pressures respectively,shown in Table 9.3.

a) Strength test pressure Pt = 0.90 (2 MYS x t) = 1.25 PrDo

b) Rated pressure Pr = 0.72 (2 MYS x t)Do

c) Hoop stress «h = PtDo or = PrDo2t 2t

wherePt and Pr = internal pressure MPa t = steel wall thickness mm Do = outside diameter of steel shell mm «h = hoop stress MPaMYS = minimum yield strength MPa

The lining has been ignored in the calculation of pressures for CMLpipe. The steel shell is assumed to act alone.

Steel strengthThe Nominal Minimum Yield Strength (MYS) values used for thethicknesses given in Table 9.1 are given in Table 8.4.

Table 9.1 - Maximum recommended steel hoop stresses

Steel hoop stress «h

The maximum recommended steel hoop stresses at variousservice pressures are given in Table 9.1.

Rated pressure refers to the maximum hydrostatic pressure atwhich the pipe or fitting is suitable for sustained operation,including an allowance for transient pressures.

The recommended maximum field test pressure is limited to the Manufacturing Proof Test as defined in AS 1579 (90% ofMYS). Typically the field test pressure would be 1.25 x maximumworking pressure.

Hydrostatic pressure limitsThe hydrostatic pressures calculated on the basis of the allowable steelhoop stresses given in Table 9.1 are subject to the following limits:Pt = 8.5 MPaPr = 6.8 MPa

The limits apply principally to pipe with D/t ratios less than 50 andrarely occur. They are set in consideration of the practicality ofachieving the test pressures necessary to reach the relevant steelwall proving stress.

9.3 Ring stiffnessCorrectly designed and installed buried flexible pipes deflect underload, to be restrained by passive pressure from the surroundingsoil. See Figure 9.1.

The installation is a composite pipe-soil structure acting integrallyto carry imposed loads.

The degree to which the pipe depends on the soil for support is afunction of the ring stiffness of the pipe. Ring stiffness is alsorequired to resist buckling.

For the purpose of calculating ring stiffness of pipes, the outsidediameter has been used. This simplifies calculation and givesconservative values.

Stiffness as a function of radius ‘r’A convenient form of calculating ring stiffness Sr as a function ofradius is:

Sr = E I x 106 N/m/mrm3

where Sr = ring bending stiffness measured in N/m

of deflection per m of pipe N/m/mE = Modulus of elasticity for the steel or

composite steel-cement mortar lining MPa I = second moment of area of the pipe

wall section per unit length of pipe= t3 mm4/mm

12

Category Maximum Recommended Steel Hoop Stress

(%MYS) (MPa)t F 8mm 8 < t F 16mm

Manufacture Proof / 90 270 225 Strength Test Pressure, Pt

Rated Pressure,Pr 72 216 180

S E C T I O N 9 | 61

t = steel wall thickness mm

rm= mean radius = ( D-t ) mm2

D = Pipe outside diameter mm

Sr can also be expressed as:

Sr = E x ( t )3 x 106 N/m/m12 rm

Stiffness as a function of D

Another form of ring stiffness, as a function of diameter isSD = E I x 106 N/m/m

Dm3

whereSD = ring bending stiffness measured in N/m of deflection per m ofpipe N/m/mE = Modulus of elasticity for the steel or composite steel-cementmortar lining MPa I = second moment of area of the pipe wall section per unit lengthof pipe

= t3 mm4/mm12

t = steel wall thickness mmDm = mean diameter of pipe = D-t mmD = pipe outside diameter mm

Simplified, this can also be expressed asSD = E x ( t )3 x 106

12 Dm

an inverse function of the Dm /t ratio.

This is the ring stiffness that is used in the deflection analysis ofburied pipes.

Note: Sr = 8 x SD

Moduli for elasticityYoung’s Modulus for steel is taken as 207000 MPa.

Young’s Modulus for cement mortar lining is taken as 21000 MPa.

Transformed sectionYoung’s Modulus for the composite steel-cement mortar lining isaccounted for by transforming the cement mortar lining thickness tothe equivalent thickness of steel using the ratio of respective moduli.

teq = t + T (Ecl ) mmEst

whereteq = transformed pipe wall thickness mmt = steel pipe wall thickness mmT = cement lining thickness mmEcl = Young s Modulus for cement mortar = 21000 MPaEst = Young s Modulus for steel = 207000 MPa

Thus

teq = t + 0.1 T mm

This transformation is not meant to account for the cementlined steel shell acting as a monolithic composite. A stricttransformation to account for this structural action wouldassume perfect bonding at the cement-steel interface andintegral ring action of the cement mortar lining. The transformedsection would be a ’T’ shape and have a much greater second moment of area.

The simplified teq transformation above results in a conservativeestimate of the stiffness contribution by the cement mortar lining.

Table 9.2 lists stiffness values as functions of radius and diameterfor bare steel shells and composite cement mortar lined steelshells. D/t ratios are also listed for reference.

9.4 Critical buckling pressureThe critical buckling pressure, Pcr for unsupported pipe is sometimesrequired to assess structural stability under loads that may give riseto unsupported buckling of the pipe, due to accidental removal ofthe soil support. Probability of such an event and its inclusion as aperformance criterion must be assessed by the Design Engineer.

Pcr required to cause buckling of an unsupported pipe can becalculated using the Timoshenko buckling equation.Pcr = 24 SD x 10-3 kPa

FS (1-§2)

WherePcr = critical external pressure required to cause buckling kPaFS = a factor of safety, normally equal to 2.5SD = pipe ring stiffness as a function of the diameter N/m/m§ = Poisson s Ratio = 0.27

� = % OD

MaximumdeflectionsRRJ: 2%Welded joint: 3%Note: Verticaldeflection shownleft is greatlyexaggerated forclarity of terms

Bedding reaction

Pipe section afterbackfill and compaction

loading

Pipe section before backfill and

compaction

S E C T I O N 9

Structural Properties of Pipe

Figure 9.1 - Flexible pipe deflection

62 | S E C T I O N 9

This equation ignores the assistance of soil support (see Section 13.6.)

Table 9.2 lists critical buckling pressures described above for baresteel shells and composite cement mortar lined steel shells.

Out of round effectsRing buckling resistance of unsupported pipe will be reduced by thedegree of out of roundness or deflection reached immediately priorto the onset of buckling. The reduction may be calculated from:

SDcr = E I x 106 N/m/mDB

3

The crown radius of curvature and the corresponding diameter ofthe deformed pipe can be calculated fromDB = D (1 + Df x S )

D

whereDB= pipe diameter deformed mmD = pipe diameter undeformed mmS = pipe deflection mmDf = shape factor (ref Sect. 13.4 )

= 3.33 x 10-6 (SDL ) + 0.00136E’

1.11 x 10-6 (SDL ) + 0.000151E’

E’ = effective combined soil modulus MPa

9.5 Beam section propertiesIn beam bending analyses and Table 14.1 the contribution to beamstiffness by the cement mortar lining has been ignored. The section

properties of steel shell only have been used.

Actual short term beam deflections will thus be smaller thancalculated, however long term deflections are likely to be realiseddue to creep of the CML.

The contribution of SINTAKOTE to structural properties is negligibleand has been ignored.

The second moment of area I, of the steel shell for beam bendingis calculated from:

I = L x (D4-d4) mm4

64

≈Lrm3t

where I = the second moment of area of the pipe cross section mm4

D = outside diameter of the pipe mmd = inside diameter of the pipe mm

rm = pipe mean radius = (D-t) mm2

The elastic section modulus Z, of the steel shell for beam bendingis calculated from:Z = L (D4-d4) mm3

(32 D)

= 2 x ID

≈Lrm2t

Table 9.2 lists the section properties I and Z described above forbare steel shells.

S E C T I O N 9 | 63

Table 9.2 – Structural properties of steel pipes

Pipe Dimensions Steel Shell Composite shell & lining

Shell CL SK Ring Stiffness Beam Bending Ring Stiffness

OD t T ts Dm/t Sr SD Pcr I x 106 Z x 103 teq Dm/teq Sr SD Pcr

mm mm mm mm N/m/m N/m/m kPa mm4 mm3 mm N/m/m N/m/m kPa

114 4.8 9 1.6 22.8 11720196 1465025 15170 2 43 5.7 19.1 19761220 2470153 25578

168 4.5 9 1.6 36.3 2877156 359644 3724 8 92 5.4 30.2 5007839 625980 6482

168 5.0 9 1.6 32.6 3983147 497893 5156 9 101 5.9 27.6 6587938 823492 8527

190 4.5 9 1.6 41.2 1970085 246261 2550 11 119 5.4 34.3 3429035 428629 4438

190 5.0 9 1.6 37.0 2724419 340552 3526 12 131 5.9 31.3 4506062 563258 5832

219 5.0 9 1.6 42.8 1760142 220018 2278 19 176 5.9 36.2 2911193 363899 3768

240 5.0 9 1.6 47.0 1329185 166148 1720 25 212 5.9 39.7 2198410 274801 2846

257 5.0 9 1.6 50.4 1077922 134740 1395 31 245 5.9 42.6 1782833 222854 2308

273 5.0 9 1.6 53.6 896158 112020 1160 38 277 5.9 45.3 1482204 185275 1919

290 5.0 12 1.8 57.0 745169 93146 965 45 314 6.2 45.8 1432746 179093 1854

305 5.0 12 1.8 60.0 638889 79861 827 53 348 6.2 48.3 1228400 153550 1590

324 5.0 12 1.8 63.8 531394 66424 688 64 394 6.2 51.3 1021719 127715 1322

324 6.0 12 1.8 53.0 926940 115867 1200 76 468 7.2 44.1 1613387 201673 2088

337 5.0 12 1.8 66.4 471384 58923 610 72 427 6.2 53.4 906336 113292 1173

337 6.0 12 1.8 55.2 821957 102745 1064 85 507 7.2 45.9 1430658 178832 1852

356 5.0 12 1.8 70.2 398903 49863 516 85 477 6.2 56.5 766977 95872 993

356 6.0 12 1.8 58.3 695230 86904 900 101 568 7.2 48.5 1210085 151261 1566

406 5.0 12 1.8 80.2 267520 33440 346 127 624 6.2 64.5 514364 64296 666

406 6.0 12 1.8 66.7 465750 58219 603 151 743 7.2 55.4 810662 101333 1049

419 5.0 12 1.8 82.8 243102 30388 315 139 665 6.2 66.6 467415 58427 605

419 6.0 12 1.8 68.8 423139 52892 548 166 792 7.2 57.2 736495 92062 953

457 5.0 12 1.8 90.4 186799 23350 242 181 794 6.2 72.7 359160 44895 465

457 6.0 12 1.8 75.2 324940 40618 421 216 946 7.2 62.5 565575 70697 732

457 8.0 12 1.8 56.1 780567 97571 1010 284 1245 9.2 48.7 1193890 149236 1545

457 10.0 12 1.8 44.7 1545100 193137 2000 351 1536 11.2 39.8 2180882 272610 2823

502 5.0 12 1.8 99.4 140514 17564 182 241 960 6.2 79.9 270168 33771 350

502 6.0 12 1.8 82.7 244280 30535 316 288 1146 7.2 68.7 425182 53148 550

502 8.0 12 1.8 61.8 586095 73262 759 379 1509 9.2 53.6 896442 112055 1160

508 5.0 12 1.8 100.6 135546 16943 175 250 984 6.2 80.9 260615 32577 337

508 6.0 12 1.8 83.7 235625 29453 305 298 1174 7.2 69.6 410118 51265 531

508 8.0 12 1.8 62.5 565248 70656 732 393 1546 9.2 54.2 864556 108070 1119

S E C T I O N 9


64 | S E C T I O N 9





508 10.0 12 1.8 49.8 1117355 139669 1446 485 1910 11.2 44.4 1577127 197141 2041

559 5.0 12 2.0 110.8 101452 12681 131 334 1195 6.2 89.1 195063 24383 252

559 6.0 12 2.0 92.2 176261 22033 228 399 1426 7.2 76.6 306792 38349 397

559 8.0 12 2.0 68.9 422371 52796 547 526 1881 9.2 59.8 646024 80753 836

559 10.0 12 2.0 54.9 833992 104249 1079 650 2326 11.2 48.9 1177166 147146 1524

610 5.0 12 2.0 121.0 77897 9737 101 435 1426 6.2 97.3 149774 18722 194

610 6.0 12 2.0 100.7 135276 16910 175 519 1702 7.2 83.7 235456 29432 305

610 8.0 12 2.0 75.3 323862 40483 419 686 2248 9.2 65.3 495352 61919 641

610 10.0 12 2.0 60.0 638889 79861 827 848 2782 11.2 53.5 901781 112723 1167

648 5.0 12 2.0 128.6 64887 8111 84 522 1611 6.2 103.4 124759 15595 161

648 6.0 12 2.0 107.0 112649 14081 146 624 1924 7.2 89.0 196072 24509 254

648 8.0 12 2.0 80.0 269531 33691 349 824 2542 9.2 69.4 412252 51532 534

648 10.0 12 2.0 63.8 531394 66424 688 1020 3148 11.2 56.9 750054 93757 971

660 5.0 12 2.0 131.0 61385 7673 79 552 1672 6.2 105.3 118027 14753 153

660 6.0 12 2.0 109.0 106561 13320 138 659 1997 7.2 90.6 185476 23184 240

660 8.0 12 2.0 81.5 254921 31865 330 871 2639 9.2 70.7 389906 48738 505

660 10.0 12 2.0 65.0 502503 62813 650 1079 3269 11.2 57.9 709275 88659 918

700 5.0 12 2.0 139.0 51385 6423 67 659 1883 6.2 111.8 98798 12350 128

700 6.0 12 2.0 115.7 89177 11147 115 788 2250 7.2 96.2 155218 19402 201

700 8.0 12 2.0 86.5 213221 26653 276 1041 2975 9.2 75.1 326126 40766 422

700 10.0 12 2.0 69.0 420080 52510 544 1290 3687 11.2 61.5 592935 74117 767

711 5.0 12 2.0 141.2 49020 6128 63 691 1944 6.2 113.6 94252 11781 122

711 6.0 12 2.0 117.5 85068 10633 110 826 2323 7.2 97.7 148065 18508 192

711 8.0 12 2.0 87.9 203368 25421 263 1092 3071 9.2 76.3 311055 38882 403

711 10.0 12 2.0 70.1 400613 50077 519 1353 3806 11.2 62.5 565458 70682 732

762 5.0 12 2.0 151.4 39765 4971 51 852 2236 6.2 121.8 76457 9557 99

762 6.0 12 2.0 126.0 68987 8623 89 1018 2672 7.2 104.7 120076 15009 155

762 8.0 12 2.0 94.3 164830 20604 213 1347 3535 9.2 81.8 252109 31514 326

762 10.0 12 2.0 75.2 324508 40564 420 1670 4384 11.2 67.0 458038 57255 593

800 5.0 16 2.3 159.0 34331 4291 44 987 2467 6.6 120.0 79796 9974 103

800 6.0 16 2.3 132.3 59549 7444 77 1179 2949 7.6 104.2 122131 15266 158

800 8.0 16 2.3 99.0 142224 17778 184 1561 3902 9.6 82.3 247549 30944 320

800 10.0 16 2.3 79.0 279897 34987 362 1936 4841 11.6 68.0 439515 54939 569

S E C T I O N 9 | 65





813 5.0 16 2.3 161.6 32701 4088 42 1,036 2,548 6.6 122.0 76006 9501 98

813 6.0 16 2.3 134.5 56717 7090 73 1,238 3,046 7.6 105.9 116324 14540 151

813 8.0 16 2.3 100.6 135445 16931 175 1,639 4,032 9.6 83.7 235748 29469 305

813 10.0 16 2.3 80.3 266522 33315 345 2,034 5,003 11.6 69.1 418512 52314 542

889 5.0 16 2.3 176.8 24971 3121 32 1,356 3,052 6.6 133.5 58039 7255 75

889 6.0 16 2.3 147.2 43296 5412 56 1,622 3,650 7.6 115.8 88799 11100 115

889 8.0 16 2.3 110.1 103329 12916 134 2,148 4,833 9.6 91.5 179849 22481 233

889 10.0 16 2.3 87.9 203195 25399 263 2,667 6,001 11.6 75.6 319072 39884 413

895 5.0 16 2.3 178.0 24469 3059 32 1,384 3,093 6.6 134.4 56874 7109 74

895 6.0 16 2.3 148.2 42426 5303 55 1,656 3,700 7.6 116.6 87013 10877 113

895 8.0 16 2.3 110.9 101246 12656 131 2,193 4,900 9.6 92.2 176224 22028 228

895 10.0 16 2.3 88.5 199090 24886 258 2,722 6,083 11.6 76.1 312626 39078 405

914 6.0 16 2.3 151.3 39818 4977 52 1,764 3,860 7.6 119.1 81664 10208 106

914 8.0 16 2.3 113.3 95009 11876 123 2,337 5,113 9.6 94.1 165368 20671 214

914 10.0 16 2.3 90.4 186799 23350 242 2,901 6,349 11.6 77.8 293325 36666 380

914 12.0 16 2.3 75.2 324940 40618 421 3,459 7,569 13.6 66.2 475440 59430 615

960 6.0 16 2.3 159.0 34331 4291 44 2,046 4,262 7.6 125.1 70412 8801 91

960 8.0 16 2.3 119.0 81891 10236 106 2,711 5,647 9.6 98.9 142536 17817 184

960 10.0 16 2.3 95.0 160956 20120 208 3,367 7,015 11.6 81.7 252746 31593 327

960 12.0 16 2.3 79.0 279897 34987 362 4,015 8,366 13.6 69.6 409534 51192 530

972 6.0 16 2.3 161.0 33068 4133 43 2,124 4,370 7.6 126.7 67820 8477 88

972 8.0 16 2.3 120.5 78871 9859 102 2,815 5,791 9.6 100.2 137279 17160 178

972 10.0 16 2.3 96.2 155008 19376 201 3,496 7,194 11.6 82.8 243405 30426 315

972 12.0 16 2.3 80.0 269531 33691 349 4,170 8,580 13.6 70.5 394368 49296 510

1016 6.0 16 2.3 168.3 28931 3616 37 2,428 4,779 7.6 132.5 59337 7417 77

1016 8.0 16 2.3 126.0 68987 8623 89 3,218 6,334 9.6 104.7 120076 15009 155

1016 10.0 16 2.3 100.6 135546 16943 175 3,998 7,871 11.6 86.6 212844 26605 275

1016 12.0 16 2.3 83.7 235625 29453 305 4,770 9,389 13.6 73.7 344758 43095 446

1035 6.0 16 2.3 171.5 27358 3420 35 2,567 4,961 7.6 135.0 56110 7014 73

1035 8.0 16 2.3 128.4 65229 8154 84 3,403 6,576 9.6 106.7 113534 14192 147

1035 10.0 16 2.3 102.5 128147 16018 166 4,229 8,173 11.6 88.2 201226 25153 260

1035 12.0 16 2.3 85.3 222739 27842 288 5,046 9,750 13.6 75.1 325903 40738 422

1067 6.0 16 2.3 176.8 24957 3120 32 2,814 5,275 7.6 139.2 51185 6398 66

1067 8.0 16 2.3 132.4 59492 7437 77 3,731 6,994 9.6 110.0 103550 12944 134

S E C T I O N 9


66 | S E C T I O N 9



OD t T ts Dm/t Sr SD Pcr I x 106 Z x 103 teq Dm/teq Sr SD Pcrmm mm mm mm N/m/m N/m/m kPa mm4 mm3 mm N/m/m N/m/m kPa

1067 10.0 16 2.3 105.7 116857 14607 151 4,638 8,693 11.6 90.9 183497 22937 238

1086 8.0 16 2.3 134.8 56402 7050 73 3,936 7,248 9.6 112.0 98170 12271 127

1086 10.0 16 2.3 107.6 110775 13847 143 4,893 9,010 11.6 92.6 173947 21743 225

1086 12.0 16 2.3 89.5 192491 24061 249 5,839 10,752 13.6 78.8 281645 35206 365

1124 8.0 16 2.3 139.5 50834 6354 66 4,367 7,770 9.6 116.0 88480 11060 115

1124 10.0 16 2.3 111.4 99821 12478 129 5,429 9,661 11.6 95.8 156747 19593 203

1124 12.0 16 2.3 92.7 173424 21678 224 6,480 11,531 13.6 81.6 253747 31718 328

1145 8.0 16 2.3 142.1 48069 6009 62 4,618 8,066 9.6 118.2 83667 10458 108

1145 10.0 16 2.3 113.5 94383 11798 122 5,742 10,030 11.6 97.6 148207 18526 192

1145 12.0 16 2.3 94.4 163958 20495 212 6,855 11,973 13.6 83.2 239897 29987 311

1200 8.0 16 2.3 149.0 41718 5215 54 5,321 8,868 9.6 123.9 72612 9076 94

1200 10.0 16 2.3 119.0 81891 10236 106 6,618 11,030 11.6 102.4 128592 16074 166

1200 12.0 16 2.3 99.0 142224 17778 184 7,902 13,170 13.6 87.2 208097 26012 269

1219 8.0 16 2.3 151.4 39785 4973 51 5,580 9,154 9.6 125.8 69247 8656 90

1219 10.0 16 2.3 120.9 78091 9761 101 6,940 11,387 11.6 104.0 122624 15328 159

1219 12.0 16 2.3 100.6 135613 16952 176 8,287 13,597 13.6 88.6 198424 24803 257

1283 8.0 19 2.3 159.4 34089 4261 44 6,512 10,151 9.9 128.4 65144 8143 84

1283 10.0 19 2.3 127.3 66895 8362 87 8,102 12,629 11.9 106.7 113513 14189 147

1283 12.0 19 2.3 105.9 116141 14518 150 9,676 15,084 13.9 91.3 181579 22697 235

1290 8.0 19 2.3 160.3 33534 4192 43 6,620 10,263 9.9 129.1 64083 8010 83

1290 10.0 19 2.3 128.0 65804 8225 85 8,236 12,769 11.9 107.3 111661 13958 145

1290 12.0 19 2.3 106.5 114243 14280 148 9,837 15,251 13.9 91.8 178611 22326 231

1404 8.0 19 2.3 174.5 25971 3246 34 8,547 12,175 9.9 140.6 49630 6204 64

1404 10.0 19 2.3 139.4 50944 6368 66 10,638 15,154 11.9 116.9 86446 10806 112

1404 12.0 19 2.3 116.0 88411 11051 114 12,711 18,107 13.9 99.9 138224 17278 179

1416 8.0 19 2.3 176.0 25313 3164 33 8,769 12,386 9.9 141.8 48372 6047 63

1416 10.0 19 2.3 140.6 49650 6206 64 10,915 15,417 11.9 117.9 84251 10531 109

1416 12.0 19 2.3 117.0 86163 10770 112 13,043 18,422 13.9 100.8 134710 16839 174

1422 8.0 19 2.3 176.8 24992 3124 32 8,882 12,492 9.9 142.4 47759 5970 62

1422 10.0 19 2.3 141.2 49020 6128 63 11,056 15,549 11.9 118.4 83182 10398 108

1422 12.0 19 2.3 117.5 85068 10633 110 13,211 18,581 13.9 101.2 132998 16625 172

1440 8.0 19 2.3 179.0 24061 3008 31 9226 12813 9.9 144.1 45981 5748 60

S E C T I O N 9 | 67





1440 10.0 19 2.3 143.0 47192 5899 61 11,484 15,950 11.9 119.9 80080 10010 104

1440 12.0 19 2.3 119.0 81891 10236 106 13,723 19,060 13.9 102.5 128032 16004 166

1451 10.0 19 2.3 144.1 46120 5765 60 11,751 16,197 11.9 120.8 78260 9782 101

1451 12.0 19 2.3 119.9 80028 10003 104 14,043 19,356 13.9 103.3 125118 15640 162

1451 16.0 19 2.3 89.7 191286 23911 248 18,569 25,595 17.9 80.0 269082 33635 348

1500 10.0 19 2.3 149.0 41718 5215 54 12,991 17,321 11.9 124.9 70790 8849 92

1500 12.0 19 2.3 124.0 72379 9047 94 15,527 20,702 13.9 106.8 113160 14145 146

1500 16.0 19 2.3 92.8 172957 21620 224 20,537 27,382 17.9 82.8 243298 30412 315

1575 10.0 19 2.3 156.5 36003 4500 47 15,053 19,115 11.9 131.2 61093 7637 79

1575 12.0 19 2.3 130.3 62452 7806 81 17,995 22,850 13.9 112.2 97639 12205 126

1575 16.0 19 2.3 97.4 149177 18647 193 23,810 30,235 17.9 87.0 209847 26231 272

1600 10.0 19 2.3 159.0 34331 4291 44 15,786 19,732 11.9 133.3 58256 7282 75

1600 12.0 19 2.3 132.3 59549 7444 77 18,872 23,590 13.9 114.0 93100 11638 121

1600 16.0 19 2.3 99.0 142224 17778 184 24,974 31,218 17.9 88.4 200067 25008 259

1626 10.0 19 2.3 161.6 32701 4088 42 16,573 20,385 11.9 135.5 55489 6936 72

1626 12.0 19 2.3 134.5 56717 7090 73 19,814 24,372 13.9 115.9 88673 11084 115

1626 16.0 19 2.3 100.6 135445 16931 175 26,224 32,256 17.9 89.8 190530 23816 247

1750 10.0 19 2.3 174.0 26196 3274 34 20,688 23,644 11.9 145.9 44451 5556 58

1750 12.0 19 2.3 144.8 45423 5678 59 24,741 28,275 13.9 124.8 71015 8877 92

1750 16.0 19 2.3 108.4 108416 13552 140 32,762 37,442 17.9 96.7 152508 19064 197

1829 10.0 19 2.3 181.9 22929 2866 30 23,636 25,846 11.9 152.5 38907 4863 50

1829 12.0 19 2.3 151.4 39752 4969 51 28,270 30,913 13.9 130.5 62149 7769 80

1829 16.0 19 2.3 113.3 94852 11856 123 37,446 40,947 17.9 101.1 133428 16679 173

1981 10.0 19 2.3 197.1 18023 2253 23 30,070 30,358 11.9 165.2 30582 3823 40

1981 12.0 19 2.3 164.1 31238 3905 40 35,974 36,320 13.9 141.4 48839 6105 63

1981 16.0 19 2.3 122.8 74499 9312 96 47,676 48,133 17.9 109.6 104798 13100 136

2159 10.0 19 2.3 214.9 13905 1738 18 38,974 36,104 11.9 180.2 23595 2949 31

2159 12.0 19 2.3 178.9 24095 3012 31 46,639 43,204 13.9 154.2 37671 4709 49

2159 16.0 19 2.3 133.9 57434 7179 74 61,840 57,286 17.9 119.5 80793 10099 105

S E C T I O N 9


68 | S E C T I O N 9

Pipe Wall Manufacturing Test Rated

OD Thickness Pressure Pressure

mm mm MPa m MPa m



mm mm MPa m MPa m

114 4.8 8.50 866 6.80 693168 4.5 8.50 866 6.80 693168 5 8.50 866 6.80 693190 4.5 8.50 866 6.80 693190 5 8.50 866 6.80 693

219 5 8.50 866 6.80 693240 5 8.50 866 6.80 693257 5 8.50 866 6.80 693273 5 8.50 866 6.80 693290 5 8.50 866 6.80 693

305 5 8.50 866 6.80 693324 5 8.33 849 6.67 679324 6 8.50 866 6.80 693337 5 8.01 817 6.41 653337 6 8.50 866 6.80 693356 5 7.58 773 6.07 618356 6 8.50 866 6.80 693

406 5 6.65 678 5.32 542406 6 7.98 813 6.38 651419 5 6.44 657 5.16 525419 6 7.73 788 6.19 630457 5 5.91 602 4.73 482457 6 7.09 723 5.67 578457 8 8.50 866 6.80 693457 10 8.50 866 6.80 693

502 5 5.38 548 4.30 439502 6 6.45 658 5.16 526502 8 8.50 866 6.80 693508 5 5.31 542 4.25 433508 6 6.38 650 5.10 520508 8 8.50 866 6.80 693508 10 8.50 866 6.80 693559 5 4.83 492 3.86 394559 6 5.80 591 4.64 473559 8 7.73 788 6.18 630559 10 8.05 820 6.44 656

610 5 4.43 451 3.54 361610 6 5.31 541 4.25 433610 8 7.08 722 5.67 577610 10 7.38 752 5.90 601648 5 4.17 425 3.33 340648 6 5.00 510 4.00 408648 8 6.67 679 5.33 544648 10 6.94 708 5.56 566

660 5 4.09 417 3.27 334660 6 4.91 500 3.93 400660 8 6.55 667 5.24 534660 10 6.82 695 5.45 556

700 5 3.86 393 3.09 314700 6 4.63 472 3.70 377700 8 6.17 629 4.94 503700 10 6.43 655 5.14 524711 5 3.80 387 3.04 310711 6 4.56 464 3.65 372711 8 6.08 619 4.86 495711 10 6.33 645 5.06 516762 5 3.54 361 2.83 289762 6 4.25 433 3.40 347762 8 5.67 578 4.54 462762 10 5.91 602 4.72 481

800 5 3.38 344 2.70 275800 6 4.05 413 3.24 330800 8 5.40 550 4.32 440800 10 5.63 573 4.50 459813 5 3.32 338 2.66 271813 6 3.99 406 3.19 325813 8 5.31 542 4.25 433813 10 5.54 564 4.43 451889 5 3.04 310 2.43 248889 6 3.64 371 2.92 297889 8 4.86 495 3.89 396889 10 5.06 516 4.05 413895 5 3.02 307 2.41 246895 6 3.62 369 2.90 295895 8 4.83 492 3.86 394895 10 5.03 512 4.02 410

914 6 3.54 361 2.84 289914 8 4.73 482 3.78 385914 10 4.92 502 3.94 401914 12 5.91 602 4.73 482960 6 3.38 344 2.70 275960 8 4.50 459 3.60 367960 10 4.69 478 3.75 382960 12 5.63 573 4.50 459972 6 3.33 340 2.67 272972 8 4.44 453 3.56 362972 10 4.63 472 3.70 377972 12 5.56 566 4.44 453

1016 6 3.19 325 2.55 260

Table 9.3 - SINTAKOTE pipe manufacturing test pressure and rated pressure

S E C T I O N 9 | 69



mm mm MPa m MPa m



mm mm MPa m MPa m

1016 8 4.25 433 3.40 3471016 10 4.43 451 3.54 3611016 12 5.31 542 4.25 4331035 6 3.13 319 2.50 2551035 8 4.17 425 3.34 3401035 10 4.35 443 3.48 3541035 12 5.22 532 4.17 4251067 6 3.04 309 2.43 2481067 8 4.05 413 3.24 3301067 10 4.22 430 3.37 3441067 12 5.06 516 4.05 4131086 8 3.98 405 3.18 3241086 10 4.14 422 3.31 3381086 12 4.97 507 3.98 405

1124 8 3.84 392 3.07 3131124 10 4.00 408 3.20 3261124 12 4.80 490 3.84 3921145 8 3.77 385 3.02 3081145 10 3.93 401 3.14 3201145 12 4.72 481 3.77 385

1200 8 3.60 367 2.88 2941200 10 3.75 382 3.00 3061200 12 4.50 459 3.60 3671219 8 3.54 361 2.84 2891219 10 3.69 376 2.95 3011219 12 4.43 451 3.54 3611283 8 3.37 343 2.69 2751283 10 3.51 357 2.81 2861283 12 4.21 429 3.37 3431290 8 3.35 341 2.68 2731290 10 3.49 356 2.79 2841290 12 4.19 427 3.35 341

1404 8 3.08 314 2.46 2511404 10 3.21 327 2.56 2611404 12 3.85 392 3.08 3141416 8 3.05 311 2.44 2491416 10 3.18 324 2.54 2591416 12 3.81 389 3.05 3111422 8 3.04 310 2.43 2481422 10 3.16 323 2.53 2581422 12 3.80 387 3.04 3101440 8 3.00 306 2.40 2451440 10 3.13 318 2.50 2551440 12 3.75 382 3.00 3061451 10 3.10 316 2.48 2531451 12 3.72 379 2.98 3031451 16 4.96 506 3.97 405

1500 10 3.00 306 2.40 2451500 12 3.60 367 2.88 2941500 16 4.80 489 3.84 3911575 10 2.86 291 2.29 2331575 12 3.43 349 2.74 2801575 16 4.57 466 3.66 373

1600 10 2.81 287 2.25 2291600 12 3.38 344 2.70 2751600 16 4.50 459 3.60 3671626 10 2.77 282 2.21 2261626 12 3.32 338 2.66 2711626 16 4.43 451 3.54 361

1750 10 2.57 262 2.06 2101750 12 3.09 314 2.47 2521750 16 4.11 419 3.29 335

1829 10 2.46 251 1.97 2011829 12 2.95 301 2.36 2411829 16 3.94 401 3.15 321

1981 10 2.27 232 1.82 1851981 12 2.73 278 2.18 2221981 16 3.63 370 2.91 296

2159 10 2.08 212 1.67 1702159 12 2.50 255 2.00 2042159 16 3.33 340 2.67 272

Manufacturing test pressure = 90% of yield stress of steel, but not greater than 8.5MPa

Rated pressure = 72% of yield stress of steel, but not greater than 6.8MPa

Working pressure is determined by the designer after consideration of the Rated Pressure of the pipe and fittings and taking into account the various factors such as external loadsand transient hydrostatic conditions.

Yield stress of steel = 300 MPa for t<=8.0mm, 250 MPa for t>8.0mm.

where t is steel wall thickness (mm).

S E C T I O N 9


HydraulicCharacteristicsof Pipe & Fittings

70

section10

72 | S E C T I O N 1 0

The flow capacity of a pipeline depends on the head driving theflow, the diameter and length of the pipe, the condition of theinterior surface of the pipe and the number and type of fittings inthe line.

The flow velocity in water supply pipes usually does not exceed 3 m/s and is often below 1.5 m/s. At high flow velocities there isa risk of cavitation occurring at discontinuities in the pipeline,such as bends, joints, tees etc. To avoid this, the recommendedmaximum flow velocities are:

4 m/s for CML pipelines

6 m/s for FBPE pipelines

10.1 Colebrook-White formulaA number of formulae exist for calculation of friction losses along apipeline.

The Colebrook-White formula below is the most recently developedand is regard internationally as the most accurate basis forhydraulic design.

v = -2√2gdSg. log10 ( k + 2.51§ )

3.7d d√2gdSg

where:v = flow velocity m/s g = acceleration due to gravity 9.81 m/s2

d = internal diameter of pipe m Sg = hydraulic gradient (head loss/unit length) m/m k = linear measure of roughness m § = kinematic viscosity of water

= 0.11425 x 10-5 at 15° Celsius m2/s

10.2 k valuesThe recommended value of k for cement mortar lined steel pipes is0.01 to 0.06mm as per Table 1 of draft AS 2200 “Design charts forwater supply and sewerage.”

Experiments carried out by Tyco Water in collaboration with theWater Research Laboratory - University of NSW, at the State Rivers& Water Supply Commission of Victoria Hydraulic ExperimentalStation, resulted in a k value of 0.01mm with water at 20°C for newcement lined steel pipe. Therefore values of k in the lower range ofthe variation shown in Table 1 of draft AS 2200 should be chosenwhen determining head losses.

For SINTAPIPE, k values are of the order of 0.003 to 0.015mm perAS 2200, but the actual value taken should represent any film thatmay build up on the surface.

10.3 Flow chart for mild steel cementmortar lined pipePipe flow friction charts provide a convenient graphical means ofsolving the Colebrook-White formula and are sufficiently accuratefor most practical purposes.

Recommended values of k for new steel pipelines are:0.003 mm for SINTAPIPE0.03 mm for CML pipe and CML seal coated pipe

Graphs 10.1 and 10.2 are based on the Colebrook – Whiteformula, using k values of 0.003 and 0.03mm, and indicate thehydraulic gradient along a straight run of pipe.

Where the number of fittings is high compared with pipe length headlosses can be calculated using minor loss coefficients from Table 10.1.

Bringing water to wine – Barossa Valley, South Australia.

S E C T I O N 1 0 | 73

Graph 10.1 – Pipe flow and head loss , k = 0.003

Hydraulic gradient in percent

Dis

char

ge ‘Q

’ in

litre

s/se

cond

Velocity ‘v’ in metres/second

Inte

rnal

dia

met

er ‘d

’ in

mill

imet

res

S E C T I O N 1 0

Hydraulic Characteristics of Pipe and Fittings

74 | S E C T I O N 1 0

Graph 10.2 – Pipe flow and head loss , k = 0.03

Hydraulic gradient in percent

Dis

char

ge ‘Q

’ in

litre

s/se

cond

Velocity ‘v’ in metres/second

Inte

rnal

dia

met

er ‘d

’ in

mill

imet

res

S E C T I O N 1 0 | 75

S E C T I O N 1 0


Type of fittings KL Type of fittings KL

1) Entry losses 5) Sudden enlargementsSharp edged entrance 0.50 Inlet dia: Outlet dia.Re-entrant entrance 0.80 4:5 0.15Rounded entrance 0.25 3:4 0.20Bellmouthed entrance 0.05 2:3 0.35Footvalve and strainer 2.50 1:2 0.60

1:3 0.802 )Radiused bends 1:5 and over 1.00Elbows(R/D - 0.5 approx) 22.5° 0.20 6) Sudden contractions

45° 0.40 Inlet dia:Outiet dia.90° 1.00 5:4 0.15

4:3 0.20Close radius bends 3:2 0.30(R/D - 1 approx.) 22.5° 0.15 2:1 0.35

45° 0.30 3:1 0.4590° 0.75 5:1 and over 0.50

Long radius bends 7) Tapers(R/D - 2 to 7) 22.5° 0.10 Flow to small end = 0

45° 0.20 Flow to large end90° 0.40 Inlet dia.: Outlet dia.

4:5 0.03Sweeps 3:4 0.04(R/D - 8 to 50) 22.5° 0.05 1:2 0.12

45° 0.1090° 0.20 8) Valves

Gate valve - fully open 0.123) Tees - 25% closed 1.00Flow in line 0.35 - 50% closed 6.00Line to branch or branch - 75% closed 24.00to line:-

sharp-edged 1.20 Globe valve 10.00radiused 0.80 Right angle valve 5.00

Reflux valve 1.00

4) Angle branchesFlow in line 0.35 9) Exit lossesLine to branch or branch to line:- Sudden enlargement 1.0030°angle 0.40 Bellmouthed outlet 0.2045° angle 0.6090° angle 0.80

Table 10.1 - Pipeline fittings loss coefficients

S E C T I O N 1 0 | 77

78 | S E C T I O N 1 0

10.4 Pipeline fittings lossesValues of KL given in Table 10.1are taken from Skeat (ref 8) andrelated to head loss by the equation:

HL = KLv2

2g m

where

HL = head loss in metres head of water mv = flow velocity m/sg = acceleration due to gravity 9.81 m/s2

KL = minor loss coefficient

Mitred bendsMitred bends are less efficient hydraulically than radiused bends,however they can be readily fabricated to suit specific geometricalneeds.

Loss coefficients vary markedly with Reynolds number (R) andnormally, to a lesser extent, with inlet and outlet arrangements andsurface roughness.

Single mitresThe coefficients given below are defined at a Reynolds number of106, with long and hydraulically smooth inlet and outlet pipes. Miller(ref 9, chapter 9) gives correction factors for other inlet outletarrangements and roughness.

Composite mitresThe equivalent circular arc re, needed for re/d values, can becalculated using:re =(a)cot(90)2 2n

wherere = equivalent radius mma = centreline length mmn = number of individual mitres

90° Composite bend KL

90° re /dComposite

Bend 1.0 1.5 2.0 3.0 4.0

2 x 45° 0.45 0.35 0.31 0.35 0.40

3 x 30° 0.42 0.33 0.27 0.21 0.23

4 x 22.5° 0.40 0.31 0.25 0.19 0.19

Other anglesCoefficients for combinations of two single mitres can be derivedfrom:

KLE = (KL1 + KL2) x Cbb

WhereCbb = headloss coefficient factor for bends

KLE = Effective headloss coefficient

KL1 = headloss coefficient bend 1

KL2 = headloss coefficient bend 2

re/d 1 2 3

Cbb 0.82 0.73 0.78

Reynolds number correctionThe following factors derived from Miller (ref 9, Figure 9.3) can beused to adjust for Reynolds number variation.

£° 111/4 221/2 45 60 90

K1 0.03 0.07 0.30 0.50 1.15

£°

£°

S E C T I O N 1 0 | 79

R x103 50 100 200 500 1000 5000

re/d

1 1.5 1.25 1.0 1.0 1.0 1.0

1.5 1.6 1.4 1.25 1.0 1.0 1.0

>2 1.65 1.5 1.3 1.15 1.0 0.8

Reynolds numberR = vd = vdª

§ µ

wherev = water velocity m/sd = inside diameter of pipe mm§= kinematic viscosity m2/s µ= dynamic viscosity kg/ms ª= density kg/m3

10.5 Flow calculation examples

Example 1. Find d given discharge Q and hydraulicgradient SgDetermine the diameter of pipe required to discharge 1000litres/second if pipeline length is 5km of CML pipe and the availablehead is 15 metres.

Hydraulic gradient is 15/5000 = 0.3%

From Graph 10.2 an internal diameter of 800mm is required.

From Table 5.1 select a 914mm OD x 6mm wall thickness pipewith 16mm thick cement mortar lining.

(Actual mean bore = 870mm)

From Table 9.3 permissible working head for this pipe is 289 metres.

From Graph 10.2 flow velocity is 2.1m/s - well within normal limits.

Example 2. Find Sg given Q and d.Determine the friction head when pumping 600 litres per second alonga 15km pipeline consisting of 750mm nominal bore MSCL pipe.

Pipe 762mm OD

Steel wall thickness 6mm

Mean bore from Table 5.1 = 726mm

From Graph 10.2 hydraulic gradient is 0.18%

Head loss over 15km = 15000 x (0.18/100) = 27 m

From Graph 10.2 flow velocity is 1.50m/s - well within normal limits.

Example 3. Find Q given d and Sg.Given an existing 5km, 900NB MSCL pipeline between tworeservoirs with an elevation difference of 20m.

Find the maximum flow rate.

From Table 5.1 mean bore of 914mm OD x 8mm steel wallthickness, with 16mm CML pipeline = 866mm.

Hydraulic gradient = 20/5000 = 0.4%

From Graph 10.2 flow rate = 1420 l/s, velocity = 2.4m/s - wellwithin acceptable limits.

13.5m long SINTAJOINT steel pipe.

S E C T I O N 1 0


Water Hammer

80

section11

82 | S E C T I O N 1 1

11.1 General formulaThe formula used to establish the wall thickness required toaccommodate internal pressure is the Barlow formula (refer also toSection 9.2):

t = PDo

2«all

wheret = steel wall thickness mm

P = internal design pressure MPa

Do = outside diameter of pipe mm

«all = allowable hoop stress MPa

11.2 Steel stressIt is recommended that «all should not exceed 72% of theminimum yield strength (MYS) of the steel, under hydrostatic orsteady state working pressure.

Where a detailed hydrodynamic analysis is carried out the effect oftransient surge pressures together with static pressure may betaken to 90% of the minimum yield strength (MYS).

11.3 Water hammerWater hammer is caused by a sudden change of flow velocity in apipeline, causing shock waves to travel upstream and downstreamfrom the point of origin.

The shock waves cause increases and decreases in pressure asthey travel at the speed of sound through the fluid along thepipeline.

Their reflection and interaction can lead to significant changes inpressure above and below those prevailing in the static or steadystate operation of the pipeline.

Potential water hammer problems should be investigated at thedesign stage. They are caused by events such as

• rapid valve closure

• sudden pump stoppage (eg power failure)

• improper operation of surge control devices

Gravity MainsFor gravity mains, water hammer effects arise commonly throughrapid valve closure.

Valve closure within the reflection period Tr will permit shock wavesof closure to be generated prior to the return of the first reflectedshock wave to the valve.

The maximum potential pressure rise will then be generated by theinteraction of all possible shock waves. Valve closure in a periodgreater than Tr reduces the maximum surge.

Surge estimate for rapid valve closure

Joukowsky Method

For the case of a steel pipeline of length L metres, undergoinginstantaneous valve closure or a valve closure within the reflectionperiod Tr seconds, the resulting pressure rise can be estimated byJoukowsky's formula:

Sh = avg m

orSp = av

1000 MPa

where:L = length of pipeline mTr = reflection period = 2L/a sSh = head rise above normal operating head mSp = pressure rise above normal operating pressure MPaa = pressure wave velocity (celerity) m/s

= 1440

{1+ 1 (d )}0.5

100 tv = velocity of flow m/sg = acceleration due to gravity =9.81 m/s2

d = pipe internal diameter mmt = pipe wall thickness mm

Note: this formula applies to steel pipelines only.

ExampleConsider a 610mm OD x 5mm thick- SK CML RRJ- pipeline, 2 km in length with a normal operating head of 90m and a flow of160 l/s. What is the maximum surge pressure that will occur ifsudden valve closure occurs.

OD, pipe outside diameter = 610 mmt, steel wall thickness = 5 mmT, cement mortar lining thickness = 12 mmd, inside diameter of lined pipe = 576 mm

celerity a = 1440/{1+576/(100 x 5)}0.5 = 981.6 m/s

Determine flow velocity

v = Q/A

S E C T I O N 1 1 | 83

Where Q = flow rate m3/sv = velocity m/sA = bore area of lined pipe m2

v = 160 x 10-3/[L( 0.576/2)2] = 0.614 m/s

This velocity is well within acceptable limits.

Pressure rise above normal operating pressure

∆h = av/g = 981.6 x 0.614/9.81 = 61.44 m

Total head on pipe (sum of static and surge pressure)

= 90+61.44 = 151.44 m

Therefore pipe wall hoop stress

s =PDo

2t

= (151.44 x 9.81/1000) x 610/(2 x 5) = 90.62 MPa

Reflection period Tr = 2 x 2000/981.6 = 4.07 s

As the pressure rise computed above is well below the workingpressure of steel pipelines, the period for critical closure does not needto be determined. It has been calculated to illustrate the procedure ashigh velocity/head conditions should always be checked.

Allievi MethodFor water hammer caused by slowly opening or closing valves (To >> 2L/a) an approximation of the pressure change may bemade using a formula similar to Allievi's. This formula assumes thatfrom the time the first reflective wave returns to the valve until it isfully closed, the pressure remains unchanged and that the effectiveopening area of the valve is changed rectilinearly.

H = 1+ n ( n ± √ n2+4 )Ho 2

The plus is associated with the pressure rise in closing the valve,the minus with pressure drop at the time of opening.

where

n = Lvo

(TogHo)

H = head after valve operation m

Ho = head under constant flow conditions m

vo = velocity under constant flow conditions m/s

L = pipeline length m

To = time for valve closing or opening s

g = acceleration due to gravity = 9.81 m/s2

ExampleFor the previous example assume

To = 5 x 2L/a

Ho = 90m

n = 2000 x 0.61/(5 x 4.07 x 9.81 x 90) = 0.0679

H/Ho = 1+0.5 x 0.0679(0.0679±P(0.06792+4))

= 1.0703 or 0.9344

H = 96.32m or 84.09m

The maximum pressure rise in this case is 7 metres, significantlyless than the 61.44 metres calculated using Joukowsky's equation.

The examples above show that a valve in a flowing pipeline shouldbe closed slowly, and particularly for the last 10% of closure, Skeat(ref. 8) recommends the last 10% of valve closure should take atleast 10xTr.

Pumped mainsFor pumped mains water hammer effects can develop throughpump start up or stoppage.

The pressure rise during pump start up will not exceed themaximum head value on the HQ characteristic curve for thepump. However, the positive surge along the full pipe length willexceed the normal operating hydraulic grade line. This conditionshould be closely examined for long pipelines and particularlywhere thinner walled pipe has been selected away from thepumping facilities.

The sudden stoppage of pumps, such as caused by power failure,is a common cause of water hammer problems. Potentially moredamaging conditions are likely if water column separation occurs.The subsequent rejoining of water columns may cause pressuresurges sufficient to damage the pipeline. Where no separationoccurs, the maximum positive pressure at the pump delivery pointwill not exceed twice the normal operating pressure.

Typical surge profiles are shown in Figure 11.1. Locations A and Bare potential zones of column separation should the maximumnegative surge drop below the pipeline.

S E C T I O N 1 1

Water Hammer

84 | S E C T I O N 1 1

Figure 11.1 - Typical surges in a pumped system

Surge estimate for pump stoppage and start upA useful means for estimating surges in a pumped system is bysurge diagrams.

ExampleAn example has been analysed to demonstrate this method. Thefollowing steady state conditions have been assumed:

OD, pipe outside diameter = 406 mmt, steel wall thickness = 5 mm

T, CML = 12 mmpipe length = 10,000 mflow = 102 l/svelocity = 0.94 m/s

celerity = 1090 m/sstatic lift = 120 mfriction headloss = 20 mpumping head = 140 m

A surge diagram shows the system resistance curve representedas hydraulic levels and velocities.

The pressure change per unit velocity change is derived fromJoukowsky's formula, namely:

Sh = aSv g s

The pressure change equates to 111 metres for a 1 m/s velocitychange in this example. It has been assumed that thepump/motor rotational moment of inertia is insignificant, and nocolumn separation occurs over the pipeline length.

The pump stoppage condition is shown in Graph 11.1.

Prior to stoppage, the system operating point is at the intersectionof the system resistance and pump curve (a). Upon stoppage,both the pressure and flow velocity drop (b). The minimumpressure occurs when the velocity falls to zero (c).

The velocity then reverses and the pressure increases (d). Themaximum reverse velocity occurs at the intersection with the

S E C T I O N 1 1 | 85

system resistance curve (e). The flow velocity reduces andpressures increase due to the water column coming to restagainst the pump's check valve (f). The maximum pressure occurswhen the flow comes to rest (g).

The cycles of pressure and velocity-change continue until thesystem flow comes to rest at the static head condition. (h).

The pump start up condition is shown in Graph 11.2.

Prior to pump start, the system operating point is at the statichead condition (a). Upon pump start up both the pressures andflow velocities increase (b). The pressure increases to a maximumat the intersection with the pump curve (c). Then there is a drop inpressure but the flow velocities continue to increase (d).

The flow velocity continues to increase with pressures fluctuatingbetween the system resistance and pump curve (e). The systemeventually settles at the normal operating condition at theintersection of the system resistance curve and pump curve (f).

General recommendationIt is suggested that a detailed surge analysis be undertaken if there is a possibility of column separation or pipe flow velocitiesexceed 1 m/s in systems where appurtenances may suffer damage under high head.

Water hammer protection devicesThe selection of protection devices in a system should be basedon an adequate water hammer analysis. Indiscriminate selectionmay in fact exacerbate an existing water hammer problem.There are positive and negative surges present to be considered.It may be necessary to control both or either one for a particular

system. This assessment will become apparent during the waterhammer analysis.

A water hammer problem may be solved by installing a singleor combination of protection devices. Some of the commonlyused protection devices available are summarised below.

FlywheelEffective for pipeline lengths up to about 1000 metres. They dampen the negative surge upon pump stoppage andconsequently dampen the associated positive surge.

Surge towerConsists of an open ended tower. Mainly used in gravity systems,particularly hydroelectric schemes. They can be used in low headpumping systems where the height does not become excessive.They dampen both positive and negative surges.

Air vesselA pressure vessel containing air and water. They dampen bothpositive and negative surges. Their use is usually limited by cost.

One way surge tankA tank connected to the pipeline by a check valve. Allows waterentry into the pipeline following negative surge.

Pressure relief valveUsed to dampen positive surges. Can be spring loaded or pilotoperated. The pilot operated type is usually preferred wherepressure release is instant and valve closure is slow.

Computer programmesA number of companies lease out computer programmes to enablerapid, economical and accurate water hammer analysis. They areideal in modelling the incorporation of protection devices as describedabove, due to the inherent hydraulic complexity of these controls.

Care should be exercised in using these programmes however, andit is advisable that experienced operators be consulted to ensurerealistic modelling.

Further readingThe following references are recommended for further information:Parmakian (ref 14), Streeter (ref 15), Pickford (ref 16), Watters (ref 17), Webb (ref 18).

S E C T I O N 1 1

Water Hammer

86 | S E C T I O N 1 1

Graph 11.1 - Pump stoppage

Velocity in metres per second

S E C T I O N 1 1 | 87

Graph 11.2 - Pump start up

Velocity in metres per second

S E C T I O N 1 1

Water Hammer

Anchorage of Pipelines

88

section12

90 | S E C T I O N 1 2

12.1 Calculation of thrustAll pressure pipelines with unanchored flexible joints requireanchorages at changes of diameter, direction, tees, valves andblank ends to resist the thrusts developed by the internal pressures.

These static thrusts act in the directions shown in Figure 12.1.

The additional dynamic thrust associated with a change in directionof the moving water can usually be ignored unless the watervelocity is extremely high.

It is imperative that thrust restraints be designed with capacity forthe maximum pressure to which the pipeline system will besubjected. This includes field test pressure and any transientpressures associated with operation.

The magnitude of static thrusts can be calculated as follows:

At blank ends and junctions

Ts = AP x 103 kN

At bends

Re = 2Tssin£ kN2

where

A = cross sectional area based on pipe OD pluscoating thickness m2

P = internal pressure MPa

Ts = static thrust kN

Re = resultant thrust at pipe bend kN

£ = angle of deflection of bend degrees

See Table 12.1 for values of static thrusts at typical fittings over arange of pipe diameters.

See Section 12.2 for typical thrust block arrangements.

Notes:• Calculations based on pipe outside diameter, steel OD + 2 xSINTAKOTE thickness.• Thrust values rounded to nearest kN.• Dividing the above values by the safe bearing load of thesurrounding soil will give the area of the thrust block in m2.

Example:A 1200mm nominal diameter pipe at 45° bend with an internalpressure of 1.0 MPa.

Static thrust = 960 kN

Soil allowable bearing pressure = 48 kN/m2

Thus area required = 960/48 = 20.0 m2

12.2 Typical thrust block arrangements

Horizontal thrustThe thrust developed must be transferred to the undisturbed earth ofthe trench wall by anchor blocks poured against an appropriate area.

Horizontal anchor blocks must distribute thrust forces over the totalbearing area of the block so as not to exceed the safe bearingpressure of the trench wall, thus ensuring the stability of the pipelineunder test and working pressures.

See Figure 12.2.

Typical values for safe bearing pressures of various undisturbedsoils based on horizontal thrust at 0.6 metres depth are given inTable 12.2.

Vertical thrustDownward thrusts are transferred to the undisturbed ground by

Figure 12.2 - Anchor blocks horizontal planeFigure 12.1 - Static thrust diagram

Anchor block for horizontal bend

Anchor block for horizontal taperAnchor block for horizontal tee

Ts

Ts

Ts

TsTs

£

£2

Re

Re =2TsSin–

S E C T I O N 1 2 | 91

anchor blocks in the same manner as horizontal thrusts. Upwardsthrusts are counteracted by the mass of the concrete anchorblocks. See Figure 12.3.

Where the water table in the area is likely to reach the level of theanchor block the submerged mass of the block should be used inthe calculation to determine the anchor block size.

Gradient thrustPipes laid at a gradient between 1 in 10 and 1 in 6 should beanalysed for anchor block requirement. Rubber ring jointed pipeslaid on steep slopes require restraint to prevent relative movementof the individual pipes due to the component of the pipe mass andcontents acting along the direction of the gradient. See Figure 12.3.

Frictional resistance between the pipeline coating and the backfillmaterial counteract a portion of the sliding thrust. Thrust blocksshould be designed to take the balance of the force.

12.3 Alternative to anchor blocksThrust blocks are not required in a welded pipeline since theunbalanced force is transmitted into the pipeline in the form oflongitudinal stress. Where a rubber ring joint pipeline is involved, asimilar situation can be achieved by providing a number of weldedjoints on each side of a fitting where a change of direction occurs.To consider this alternative the frictional resistance of the pipeline inthe soil must be checked to determine the number of welded jointsnecessary to produce an effective anchoring embedment length.

Friction Factor µThe AWWA (ref 11) states coefficients of friction µ, between soil andsteel pipe coatings are generally in the range 0.25 to 0.40.

No data has been published for fusion bonded polyethylene andhence extensive experimental work was carried out by Tyco Waterto determine the appropriate range of values.

Results can be summarised as follows:• Where sand backfill or low clay content contact the coating, afriction coefficient of 0.32 is appropriate.• For sand backfill using Sintakote pipe with a factory applied sandcoating, a friction coefficient of 0.50 is appropriate.• Where clay soils are in contact with the coating, a frictioncoefficient of 0.16 should be used. Note that clay would notnormally be placed directly against the pipe surface.

These values should provide a reasonable degree of conservatismin designing the required length of pipeline to be welded togenerate adequate restraint.

OD + SK Thrust developed per MPa internal pressuremm kN

Blank end 90° Bend 45° Bend 22.5° Bend 11.25° Bend

200 31 44 24 12 6

300 71 100 54 28 14

600 283 400 216 110 55

750 442 625 338 172 87

1000 785 1111 601 306 154

1200 1131 1599 866 441 222

1400 1539 2177 1178 601 302

1600 2011 2843 1539 785 394

1800 2545 3599 1948 993 499

Soil type Safe bearing pressure kPa

Soft clay 24

Sand 48

Sand and gravel 72

Sand and gravel bonded with clay 96

Shale 240

Table 12.1 - Static thrust values

Figure 12.3 - Anchor blocks to resist upward and gradient thrust

Table 12.2 - Safe soil bearing pressures

Anchor block for vertical slope Anchor block for vertical bend

S E C T I O N 1 2


S E C T I O N 1 2 | 93

Anchorage lengthThe length of pipe required to balance these forces can be deducedfrom

L = PA (1-cos£) x 103

µ(2Wd+Ww+Wp)

whereL = pipeline length to be anchored m

P = internal pressure MPa

A = cross sectional area based onpipe OD + coating thickness m2

£ = angle of deflection of bend degrees

µ = soil friction coefficient

Wd = weight of backfill kN/m

Ww = weight of water in pipe kN/m

Wp = weight of pipe kN/m

12.4 Examples of thrust calculationsGiven a pipe diameter of 559mm x 5mm wall thickness, and 12mmcement lining thickness and SINTAKOTE thickness of 2 mmthickness giving a pipe OD =563mm.

Example 1. Bearing areaDetermine the lateral bearing area and anchor block size, for ahorizontal 90° bend in a pipeline and with an internal pressure of 2 MPa laid in shale.

Re = 2PA sin(£/2) x 103

= 2 x 2 x ª x (0.563/2)2 x sin (90/2) x 103

= 704.13 kN

Bearing pressure for shale = 240 kN/m2

ÏThrust block bearing area = 2.94 m2

Example 2. Embedment lengthDetermine the length of welded pipe required on each side of the90° bend in example 1 above, to avoid the need for a thrust block.

Assume that the pipe is buried under 1 metre of clayey sand, atrench 0.8m wide at pipe crown level with clay having a density of1800 kg/m3.Length of pipe required to carry the out of balance force in thedirection of the pipe.

L = PA(1-cos£) x 103 / [µ (2Wd +Ww +Wp)]where

Wd = weight of soil prism above pipe= 9.81ªDH/1000

whereª = soil density (see Table13.1) kg/m3

D = pipe outside diameter mH = height of ground surface above top of pipe m

thereforeWd = 9.81 x 1800 x 0.563 x 1.0/1000

= 9.960 kN/m

Ww = weight of water in pipe= L (0.525/2)2 x 9.81 x 1000/1000= 2.124 kN/m

Wp = weight of pipe (refer Table 5.1 pipe masses)

= 120 x 9.81/1000= 1.177 kN/m

µ = 0.32henceL = 2L/4 x (0.563)2 x (1-cos90) x 103/[0.32(2 x 9.960+2.124+1.177)]

=67.0 mIf each pipe is 12m long, then 5 joints are required to be welded.

Incorporating bend reactionIn the above calculations, the soil reaction at the bend has not beenincluded. If it were, the number of joints that have to be weldedcould be reduced.

Say the bearing pressure of clayey-sand equals 96 kPa and safetyfactor is 0.8.

Assume the length of pipe under bearing pressure is 3 diametersi.e. 1.69m long.

ÏForce available at the pipe face

= 1.69 x 0.563 x 96 x 0.8

= 73.1 kN

Ïpipe length to be welded is

= (2L/4 x (0.563)2 x (1-cos90) x 103 – 73.1 x sin90)/[0.32(2 x9.96+2.124+1.177)]

= 57.3 m

= 4 joints to be welded

Note:When the backfill depth to trench width ratio is > 10, considerationshould be given to a reduction in the weight of soil on the pipe. Forsuch an analysis using Marston's theory, designers should consultSpangler and Handy (ref 3) and AS 2566.1.

S E C T I O N 1 2


StructuralDesign forBuried Pipelines

94

section13

13.1 General considerations and procedureThe following design procedures are based on flexible pipebehaviour under load. Lateral support is generated by the passiveresistance of the soil, contributing to the load carrying performanceof the pipe.

A pipe placed in a trench must be strong enough to withstand allexternal loads which may act on it. In some instances, particularlywhen the internal pressure is low, these external loads maydetermine the wall thickness of the pipe in satisfying ring stiffnessrequirements.

Performance aspectsThe performance of the selected pipe is checked principally in two ways:

1. Ring deflection by verifying that the unpressurised pipe undertrench backfill, other superimposed distributed loads and trafficloads will not suffer excessive ring deflection.

2. Ring buckling by verifying whether the pipe has adequate shellstability or resistance to buckling to resist local external loads andinternal vacuum loads.

The combined effects of ring bending stress due to externalpressures and hoop stress due to internal pressure are generallynot significantly greater than the effects of internal pressure alone.As a result, hoop stress only is normally adequate fordetermination of wall thickness.In addition it may be necessary to assess axial and beam bendingloads. In rubber ring joint pipes correctly placed in a trench, the axialand bending loads are small and not usually taken into account.

The following methods of load calculation and performanceassessment are recommended for their ease of application andproven track record in practice.

Load calculationCalculation of soil loads is based on Marston's theory (ref 6) forflexible pipe.

Calculation of traffic wheel load effects is based on work byBoussinesq (ref 10) and the Bridge Design Code – Section Two –Design Loads – Austroads (1992).

It is to be noted that the transient loads from internal vacuum andsurface live loadings are not usually considered simultaneously.

Loads from groundwater and internal vacuum are hydrostatic innature and do not generally affect pipe ring deflection, but a checkshould be made to ensure ring buckling stability of the shell.

Compaction and effective combined soil modulus E’Depending on the ring deflection and surface settlementconsiderations of the installation, different levels of compaction canbe specified to achieve the necessary effective combined soilmodulus E’.

As a guide, non trafficable installations such as in open field wouldrequire compaction to achieve 60% density index in cohesionlessmaterials or 90% dry density ratio in cohesive materials.

Trafficable installations such as under road pavement may requirecompaction to achieve 70% density index in cohesive materials or95% dry density ratio in cohesive soils.

96 | S E C T I O N 1 3

Symbol Description

GW Well-graded gravels, gravel-sand mixtures, little or no fines

GP Poorly graded gravels, gravel sand mixtures, little or no fines

GM Silty gravels, poorly graded gravel-sand-silt mixtures

GL Clayey gravels, poorly graded gravel-sand-clay mixtures

SW Well-graded sands, gravely sands, little or no fines

SP Poorly graded sands, gravely sands, little or no fines

SM Silty sands, poorly graded sand-silt mixtures

SC Clayey sands, poorly graded sand-clay mixtures

ML Inorganic silts & very fine sand, silty or clayey fine sands

CL Inorganic clays of low to medium plasticity

MH Inorganic silts, micaceous or diatomaceous fine sandy or silty soils, elastic silts

CH Inorganic clays of high plasticity, fat clays

OL Organic silts and organic silt-clays of low plasticity

OH Organic clays of medium to high plasticity

Pt Peat and other highly organic soils

Table 13.2 - Unified Soil Classification

Source: Classification of Soils for Engineering Purposes. ASTM Standard D2487-9, ASTM, Philadelphia, Pa. (1969).

Material Unified Soil WeightClassification symbol kN/m3

(see Table 13.2)

Saturated clay CL, CH, ML, MH 21

Normal clay CL, CH, ML, MH 19

Clayey sand GM, SM, GC, SC 18

Loose granular sand GU, GW, SW, GP, SP 15

Table 13.1 - Density of backfill materials

S E C T I O N 1 3 | 97

Deflection calculationA variety of methods have been developed for the evaluation of thestructural strength of the pipe as well as the external loads actingon the pipe. A popular formula for calculation of pipe ring deflectionis that developed by MG Spangler and later modified by Watkinsand Spangler at the Iowa State University.

Other methods of deflection estimation are available and vary in theirdegree of sophistication. Some require extensive calculation usingcomputer programmes which require numerous soil parameters tobe either estimated or measured in the field for input to the analysis.

The degree of sophistication is questionable given the intrinsicvariability of soil parameters, the difficulty in their consistentestimation, their often time dependent nature and the propensityfor soil-pipe structures to be disturbed during their service life.

Generally, the Spangler-Watkins formula is preferred because of itsextensive history of successful application, ease of use andunderstanding.

Ring buckling stabilityThe ring buckling stability check where depth of cover is equal toor less than 0.5m is carried out using Timoshenko’s equation. Forcover greater than 0.5, the Moore equation, which yields similarfactors of safety to those obtained from using the moreconventional formulae based on Luscher’s equation, is adopted.

Timoshenko’s equation predicts a buckling resistance pressure fora condition of uniform external pressure without allowance for soil

support, whereas Moore’s equation is valid only where external soilsupport is present.

13.2 Design loads due to trench andembankment fillA rapid method of estimating the earth load on a flexible pipe dueto trench and embankment fill is to assume that it is equal to theweight of the earth prism directly above the pipe:wg = ~ H

wherewg = vertical design load pressure at top of pipe due to soil dead load kPa ~ = assessed unit weight of trench fill or embankment fill kN/m3

H = cover, vertical distance between the top of the pipe and the finished surface F 10D mD = pipe outside diameter m

For H > 10D results may be conservative.

Embankment conditionFor embankment condition the settlement ratio is assumed to bezero, that is settlement of the soil columns beside the pipe isassumed equal to the settlement of the soil column above the pipe.

Deep trench or embankmentFor deeper trenches and embankments, say H/B > 10,consideration should be given to side wall friction. For such ananalysis designers should consult AS 2566.1

S E C T I O N 1 3

Structural Design for Buried Pipelines

Connecting a cable across a joint on a cathodically protected SINTAJOINT pipeline.

98 | S E C T I O N 1 3

Figure 13.2 – Average load intensity

Aver

age

Load

Inte

nsity

, Wq

(kPa

)

Legend:= Single lane= Multiple lanes= HLP 320 loading= HLP 400 loading

0.5 0.6 0.8 1.0 2 4 6 8 10

Cover Height (m)

90

80

70

60

50

40

30

20

10

0

S E C T I O N 1 3 | 99

Design Loads due to superimposed loads.The design load due to a superimposed dead load shall bedetermined as follows:

• for uniformly distributed loadswgs = u = load per unit area, kPa

• for concentrated dead or live loads, it shall be determined byapplication of either

- the Boussinesq theory in Spangler and Hardy, or

- the distribution method described in section 13.3.

13.3 Superimposed Live Loads

Aircraft and railwaysFor aircraft, the appropriate superimposed live loads relatedinformation may be obtained from the relevant authority. For railways,the superimposed live loads may be obtained from AS 4799.

Road vehiclesUnless otherwise specified by the regulatory authority, road vehicleloads shall be taken as given in AUSTROADS Bridge Design Code– Section 2 and the average intensity of the design load (wq), forthese loadings is shown in Figure 13.2. (This load distributionincludes the effect of the tyre footprint)

Where the cover (H) is less than 0.4 m, a wheel or track load shallbe considered to act at the top of the pipe on an area equal to thecontact area of such load.

Where the depth of fill over a pipe is 0.4 m or more, a wheel or track

load shall be uniformly distributed at the top of the pipe, over an areasimilar to the contact area of such load, and with sides equal to 1.45H greater than the sides of the contact area. See Fig 13.3.

Where the surcharge from loads overlap, the total load shall beconsidered as uniformly distributed over the area defined by theoutside limits of the combined areas See fig 13.3

On the basis of these assumptions, the average intensity of thedesign live load at the top of the pipe due to multiple wheel ortrack vehicle loads, including impact effects, is calculated from thefollowing equation:

wq = vP|(L1L2) kPa

where

| = 1.4 – 0.15H but not less than 1.1 = impact effects

vP = sum of wheel loads kN

L1 = total wheel footprint width (fig 13.3) m

L2 = total wheel footprint length (fig 13.3) m

Construction and other equipmentAppropriate wheel or track loads for construction and otherequipment shall be obtained from the manufacturer of theequipment. Distribution and intensity of loading shall be determinedas shown above under Road Vehicles.

Note: Construction loads may be applied for cover heights lessthan the final cover height.

Figure 13.3 – Distribution of Wheel and Track Loads

Plane at top of pipe

Finished surface

L1 = vG + b + 1.45H if load prisms overlapor ( b + 1.45H ) if no overlap

L2 = a + 1.45H

S E C T I O N 1 3


100 | S E C T I O N 1 3

13.4 Deflection CalculationsThe predicted vertical deflection of a buried pipe shall satisfy thefollowing equation:Sy F SyallD DwhereSy = K x 10-3 ( wg +wgs+wq) D 8 x 10-6 x SD + 0.061 x E’

whereSy = pipe vertical deflection mSyall = allowable pipe vertical deflection m

SD = E I x 106 N/m/mDm

3

K = 0.1 (bedding constant)E’ = ¡ E’e MPa

¡ = 1.44 Sf+( 1.44 - Sf ) x ( E’e )E’n

E’e = embedment soil modulus (ref Table 13.3) MPaE’n = native soil modulus MPa

Sf = ( B/De – 1 ) F 1.441.154 + 0.444 ( B/De -1)

B = Width of the trench at the pipe spring line m

De = D = Pipe outside diameter m

13.5 Acceptable deflection limits

Welded joint pipeFor mild steel cement mortar lined pipes with welded joints a safedeflection limit of 3% of the pipe diameter is recommended.

Compaction

Low <----------------------------> High

RD (%)

- 85 90 95 100

ID (%)

- 50 60 70 80

Standard Penetration Test - Number of Blows

F4 >4 F14 >14 F24 >24 F50 >50

Gravel single size GW 5 7 7 10 14

Gravel graded GW 3 5 7 10 20

Sand and coarse-grained soil GP, SW, SP and 1 3 5 7 14with less than 12% fines GM-GL, GC-SC

Coarse-grained soil with more GM, GC, SC, SM and NA 1 3 5 10than 12% fines GM-SC, GC-SC

Fine-grained soil (LL<50%) with medium CL, ML, ML-CL, NA 1 3 5 10to no plasticity and containing more than CL-CH, ML-MH

25% coarse-grained particles

Fine-grained soil (LL<50%) with medium to CI, CL, ML, ML-CL, NA NA 1 3 7no plasticity and containing less than CL-CH, ML-MH

25% coarse-grained particles :

Fine-grained soil (LL>50%) CH, MH and CH-MH NA NA NA NA NAwith medium to high plasticity

NA = Soils in these categories require special engineering analysis to determine required density, moisture content and compaction.

RD = Dry density ratio (ref AS 1289, 5. 4.1 and 14.2) ID = Density index (ref AS 1289, 5.6.1 and 14.2)

Soil Description Soil Classification

Table 13.3 - Embedment (E’e) and native (E’n) soil moduli

This recommendation is adopted to avoid possible repetitive flexingof the pipe to an extent which could cause the cement mortarlining to fray at cracks.

It should be noted that a reduction in the deflection can in mostcases be achieved by improving the pipe bedding conditions inlocalities where the pipe will be subject to traffic loads and notnecessarily by selecting a pipe with greater wall thickness.

Rubber ring joint pipeFor RRJ pipe the safe deflection limit is 2% of the diameter toensure that the annular gap between spigot and socket is kept tolimits that assure effective gasket sealing pressure.

Ring Bending StrainRing bending strain εb can be calculated from:

εb = Df (∆y) x t ≤ εb allD d

whereεb all = allowable ring bending strainDf = shape factor

= 3.333 x 10-6 ( SD ) + 0.00136E’

1.11 x 10-6 ( SD ) + 0.000151E’

εb all = 0.001449 for t ≤ 8= 0.001208 for t > 8

( At 100% MYS, ε = σ / Efor t ≤ 8, MYS = 300 Mpa ∴ε = 300 /207000 = 0.001449for t > 8 MYS = 250 MPa ∴ε = 250 /207000 = 0.001208)

Internal PressureThe applied internal pressure Pw shall not exceed the maximumallowable pressure Pr , i.e.

Pw ≤ Pr

Pr can be obtained from Table 9.3

13.6 Combined LoadingThe response to the combined external load and internal pressuremust satisfy

Pw + rc εb ≤ 1ηpPall ηb εb all η

whereηp = ηb = η = 1.39 (ref Table 2.1 AS 2566.1 )

rc = re-rounding effect= 1- ( Pw ) for Pw ≤ 3.0 Mpa, or

3

= 0 for Pw > 3.0 Mpa

13.7 Ring buckling stabilityA buried pipeline may collapse or buckle from elastic instabilityresulting from loads or deformations.

The total of all loads should not be greater than the allowablebuckling pressure.

Maximum allowable buckling pressure

The allowable buckling pressure qall can be calculated from:

(i) For H ≥ 0.5m, the greater of

qall 1 = 24 SD x 10-3 or kPaFS (1-ν2)

qall 2 =(SD x 10-6)1/3. (E’)2/3 x 103 kPa

FS

(ii) For H < 0.5m

qall 1 = 24 SD x 10-3 kPaFS (1-ν2)

where

FS = factor of safety= 2.5 unless specified otherwise

H = height of ground surface above top of pipe m

External loads and combinationsThe summation of appropriate external loads including externalpressure and internal vacuum must satisfy the following equations:

• for H ≥ Hw

γ (H - Hw) + ( γL + γsub) x [ De ] +wgs + wq + qv ≤ qall2 + Hw

where

Hw = height of water surface above top of pipe m

γsub = (ρs -1) γρs

γ = assessed unit weight of trench or embankment fill kN/m3

γL = assessed unit weight of liquid external to the pipe= 10.0 for water kN/m3

qv = internal vacuum kPa

Note: where ρs is not known, assume ρs = 2.65

i.e γsub = 0.623 γ

• for H < Hw

γL (De / 2 + Hw) + γsub[ De ] +wgs + wq + qv ≤ qall2 + H

Note: where the possibility of concurrent application of live loadsand vacuum is unlikely, the lesser of the terms wq and qv may beomitted from the equations above.

S E C T I O N 1 3 | 101

S E C T I O N 1 3


Free Span & StructuralLoading

102

section14

104 | S E C T I O N 1 4

14.1 General considerationsDue to its high tensile strength, steel pipe is well suited to aboveground installations, enabling longer spans and fewer supportsthan are possible with other materials.

SupportsAbove ground pipelines can be supported in a number of waysdepending on such factors as pipe size, the span required andeconomics.

Where the pipe itself acts as a structural span, it may besupported on suitably padded saddles which may be fixed onpiers attached to hangers or cantilevers.

SaddlesThe angle of the contact area of saddles usually varies from 90° to 120°, with the latter being a convenient design. For equal load,the larger the contact angle the lower the saddle stresses.

Saddle supports cause critical points of stress in the steel pipe walladjacent to the saddle edges. The critical stresses are practicallyindependent of the width of the saddle and accordingly the saddlewidth may be determined by the design width of the pier orcantilever. In the case of hangers the saddle width is determinedby the choice of materials at the pipe-saddle interface.

Should overstress be encountered it is often more economical toincrease the wall thickness of the pipe than to provide stiffeningrings, especially where diameter of the pipes is 900 mm or less.This thickening may apply to the entire span or for a distance eachside of the saddle support of approximately two pipe diametersplus the width of the saddle.

Pipes should be held in each saddle by steel hold-down strapsbolted to the main structural support.

Pipe-saddle interfaceDepending on the coating finish specified for the pipe and thefrequency of any movement relative to the saddle, the interfacemay require padding.

Where coating damage is inconsequential padding is unnecessary.When coatings are to be protected in installation and againstlocalised stress a neoprene pad is recommended.

Where the pipe saddle interface must accommodate sliding, anarrangement of suitable materials must be considered. These include PTFE, teflon and aluminium. In this case thearrangement should ensure that the sliding capacity is maintained, free of possible contamination by grit or dust. Multiple strips in the padding combination may be necessary.

Sag pocketsWhere it is required to completely drain intermittently supportedpipelines, care must be taken to avoid sag pockets. To eliminatesuch pockets, each downstream support level must be lower thanthe adjacent upstream support by an amount that exceeds the sagof the pipe between the supports.

A convenient rule is to ensure the elevation of one end is higherthan the other by an amount equal to four times the deflectioncalculated at the mid span of the pipe. The required gradient, Gbetween supports is thus calculated:

G = 4 x y

L

where G = Gradienty = deflection mmL = span mm

General design considerationsIt should be remembered that the theory of flexure applies to apipe supported at intervals, held circular at and between supportsand completely filled with water.

If the pipe is only partially filled and the cross section betweensupports becomes out of round, the maximum fibre stress isconsiderably greater than indicated by the ordinary flexure formula,being highest for the half filled condition. See Schorer (ref 12).

When determining the actual position of the support centres itshould be remembered that lengths of individual pipes are subjectto manufacturing tolerances. (Refer to AS 1579).

In beam bending analyses and Table 14.1 the contribution to beamstiffness by the cement mortar lining has been ignored, as discussed inSection 9.5. The section properties of steel shell only have been used.

Actual short term beam deflections will thus be smaller thancalculated, however long term deflections are likely to be realiseddue to creep of the CML. The weight component of SINTAKOTEhas also been ignored in these analyses and Table 14.1.

14.2 Maximum span for welded joint pipelinesA welded joint pipeline supported on saddles is treated as acontinuous beam as shown below. It is recommended that weldedjoints between supports be fully welded, either by full butt weld orby double-weld lap joints. If joints at supports are thus fully weldedthe pipeline is assumed to act strictly as a continuous beam.

When single welded lap joints are employed at or near supports,

S E C T I O N 1 4 | 105

the analysis conservatively assumes the joint is not absolutely rigidand allows some moment redistribution. This effectively reducesbending moment on the joint and the maximum allowable span.

Above ground rubber ring jointed pipe supported by saddles is treatedas a simply supported beam and is considered in the next section.

Consider a welded joint pipeline. This can be treated as a built-in beam.

Bending moment at A and B - MA = MB = w L2 Nm12

Bending moment at C - MC = w L2 Nm24

where

w = (M1 +M2 +MW) x 9.81 N/mM1 = unit mass of steel shell

= 0.02466 (D – t) t kg/mM2 = unit mass of cement mortar lining

= 0.00755 ( D – 2t –T)T kg/mMW = unit mass of water, pipe full

= L (D - 2t -2T)2 kg/m4000

where

D = outside diameter of pipe mmt = steel wall thickness mmT = cement mortar lining thickness mmL = span mPs = saddle reaction Nand the density of water is taken to be 1000 kg/m3.

Maximum bending stressThe maximum bending stress «B , occurs at A and B:

«B = 1000 MB MPaZ

whereZ = elastic section modulus of pipe

= L ( D4 – d4 ) mm3

32 DR L r2 t mm3

D = outside diameter of pipe mm

d = inside diameter of pipe mm

t = wall thickness mmr = pipe mean radius = (D-t) mm

2

Cracking and spalling of Cement Lining in steel pipes occurs whenthe longitudinal bending stress in the pipe reaches 80 MPa.Therefore a tentative maximum longitudinal bending stress of 80MPa has been used in the following analysis. This limit can bechanged by the designer to suit particular requirements. Correctionfactors are included to achieve this.

By substituting MB = wL2 /12 in the bending stress equation formaximum moments at A and B and rearranging we have:

L1 = ( 12 «B Z )1/2 m

1000 w

= ( 12 x 80 x Z )1/2

1000 (M1 +M2 +MW) x 9.81 m

= ( 0.09786 Z )1/2

M1+M2+MW m

This equation holds for fully welded pipe, that is a pipe with either a full butt weld or a double weld lap joint. For spans withpipes jointed at supports with only one weld, for example, a single welded lap joint, the above equation is modified to:

L2 = ( 0.08155 Z )1/2

M1+M2+MW m to reduce the structural bending load on the single circumferential weld.

If the allowable bending stress required is other than 80 MPa, theresultant value of “L” in the above equations should be multipliedby the appropriate correction factor:

For example, if new value of «B = 65 MPathen the correction factor = (65/80)1/2 = 0.90

The recommended maximum spans for continuous fully welded (buttwelded or double lap welded) and single lap welded cement mortarlined pipe are given in Table 14.1. This table takes into account thetotal weight of pipes full of water with a density of 1000 kg/m3.

Spans have been calculated allowing for a maximum bending stress of80 MPa. This may be increased if higher bending stresses are allowableon a project. However, it is important that deflection, buckling andother stresses (Poisson, temperature and saddle stresses) also bechecked before deciding on the acceptable span.

Note: the contribution of CML to the section modulus isconservatively taken to be zero.

14.3 Maximum span for simplysupported pipelinesWhere SINTAJOINT pipelines adjoin a fully welded span or where

Figure 14.1 – Supported Beam

UDLwN/m

A C B

L

Ps Ps

S E C T I O N 1 4

Free Span and Structural Loading

106 | S E C T I O N 1 4

span support joints allow angular rotation, the span is regarded asbeing simply supported. Hence the moment at the support isminimum and taken to be zero while the maximum bendingmoment occurs at the mid-point of the span and is equal to:

MC = wL2 Nm8

Hence the span can be calculated by using the equation:

L3 = ( 0.0652 Z )1/2

M1+M2+MW m

In this equation the allowable bending stress is taken as 80 MPa. If the allowable stress is other than 80 MPa the resultant value of L3

should be multiplied by the correction factor shown in Section 14.2.

The recommended maximum spans for simply supported pipelinesare provided in Table 14.1. Once the span is determined,deflection, buckling and Poisson, temperature and saddle stressesshould be checked.

Above ground SINTAJOINT® pipesIt is recommended that with above ground rubber ring jointedpipelines, a support be located behind each socket –see figure 14.2.

Pipes must be fixed to supports with metal straps so that axialmovement due to expansion or contraction resulting from temperaturevariations is taken up at individual joints along the pipeline. In additionjoints should be assembled with spigots withdrawn 4mm to 5mm toaccommodate these thermal movements.

Pipes supported in this way are capable of free deflection andaxial movement at the joints which can accommodate any normalmovement of the pipe support. Purpose-designed anchoragemust be able to resist thrusts developed by internal pressure atbends, tees and other thrust fittings.

Suspended spans are not recommended for SINTAJOINT pipes.

Safe span for SINTAJOINT pipesSINTAJOINT pipe with diameters up to DN600 with effectivelengths of 13.5m are satisfactory for simply supported spansusing a single pipe. For sizes above DN600, shorter spans orspecial tolerance pipes are required to avoid sealing problemscaused by shear loads at the joints. In this size range adviceshould be sought from Tyco Water’s marketing offices.

14.4 DeflectionIn the case of a simply supported pipe, for example, aSINTAJOINT at supports, the mid span deflection can bedetermined from:

= 5wL4

384 E I

where = deflection mmw = [(M1 +M2 +MW) x 9.81]/ 1000 N/mmL = span of simply supported pipe mmE = Young’s modulus for steel

= 207000 MPa

I = L (D4 - d4 ) R L r3 t mm4

64

D = external diameter of the pipe mmd = internal diameter of the pipe mmr = pipe mean radius = (D-t)/2 mmt = pipe wall thickness mm

In the case of a pipe with single welded lap joints at supports, themid span deflection is determined from:

= 3 w L4 mm384 E I

For a pipe with butt welded or double welded lap joints atsupports the mid span deflection is determined from:

= w L4 mm 384 E I

Pipe deflection should be kept within 1/360 span.

14.5 Localised saddle stressThe localised saddle stress «L must be added to the bendingstress, «B in the pipe at the point of support.«L = k Ps x loge ( r )t2 t

where«L = localised saddle stress MPak = factor = 0.02-0.00012 (£s – 90)£s = saddle angle degreesPs = total load on saddle or saddle reaction Nt = pipe wall thickness mmr = outside radius of pipe mm

Figure 14.2 - Pier support for above ground SINTAJOINT pipelines

Bearing material toaccomodateexpansion

movement wherenecessary

Hold down over bearing material

As previously discussed, for an unrestrained pipe the bending stress atthe saddle, «B is approximately equal to zero. For restrained, pipe thebending stress is calculated using the theory of continuous beams.

14.6 Poisson, temperature and total stress

Poisson stressIn the case of axially restrained, that is welded joint pipelines,Poisson stress must be added to the localised saddle stress.

The Poisson stress = § «h MPawhere § = Poisson’s ratio = 0.27«h = hoop stress due to internal pressure MPa

Temperature stressTemperature changes induce stress in axially restrained pipelines.The difference between the temperature at which the pipeline wasconstructed and the service temperature should be considered, thestress «T induced being estimated by

«T = E | ST MPa

where

E = Young’s modulus for steel= 207000 MPa

| = coefficient of linear expansion for steel= 12 x 10-6 mm/mm/ °C

ST = difference between pipeline operating and installationtemperature °C

Total stressTotal stress at saddle point, «TOT = «B + «L + §«h +«T MPa

Any pipe selected must meet two requirements. Both the maximumbeam stress «B in the span and the stress at the saddle must bewithin the allowable limits. One or the other will govern. On largediameter pipes with long spans, ring girders may be necessary toensure that the pipe diameter does not distort, reducing the I valueand beam stiffness.

14.7 Example of calculation ofmaximum span and deflectionDetermine the approximate maximum span for a 762 mm OD pipewith 12 mm wall thickness lined with a 12 mm thick cement mortarlining, checking also deflections and saddle stresses. Assume thatthe working pressure is 3.0 MPa. MYS is taken to be 250 MPa, theshell being manufactured from steel plate to be to AS3678.Assume no significant temperature effect.

Section massM1 = 0.02466 (762 – 12 ) x 12

= 221.9 kg/m

M2 = 0.00755 (762 –2 x 12 – 12) x 12= 65.8 kg/m

MW = L [ 762 – 2 x 12 – 2 x 12] 2 / 4000 kg/m= 400.4

MTOT = M1 +M2 +MW

= 688 kg/m

Section propertiesMoment of inertia

I = L ( 7624 – 7384 ) 64

= 1988.55 x 106 mm4

Section Modulus

Z = 2 I D

= 5219.3 x 103 mm3

Hoop stress

«H = PD 2t

= 3 x 762 (2 x 12)

= 95.3 MPa

Safe spansCase 1 - simply supportedL3 = [ 0.06524 x 5219 x 103 ]1/2

688= 22 m

Case 2 - single weld lap joints at supportsL2 = 1.115 x 22.2 = 24.8 m

Case 3 - fully welded joints at supportsL1 = 1.225 x 22.2 = 27.2 m

If the allowable stress is reduced from 80 MPa to say 50 MPa, thespans calculated above must be corrected by a factor equal to{50/80}1/2 = 0.79

i.e L3 = 0.79 x 22.2 = 17.5mL2 = 0.79 x 24.8 = 19.6mL1 = 0.79 x 27.2 = 21.5m

Deflection checkDeflection of the pipe is determined using the deflection equationdefined in Section 14.4.

S E C T I O N 1 4 | 107

S E C T I O N 1 4


108 | S E C T I O N 1 4

Case 1 - simply supported = 5 x ( 688 x 9.81 ) x ( 220004 )384 1000 207000 x 1988 x 106

= 51.9 (L/360 = 61.7) mm

Case 2 - single welded lap joints at supports = 3 x ( 688 x 9.81 ) x ( 248004 )384 1000 207000 x 1988 x 106

= 48.5 (L/360 = 68.9) mm

Case 3 - fully welded joints at supports = 1 x ( 688 x 9.81 ) x ( 272004 )384 1000 207000 x 1988 x 106

= 23.4 (L/360 = 75.6) mm

Check saddle stressesAssume saddle angle = 120 degreesAssume maximum allowable stress - 0.6 MYSMYS = 250 MPa, thereforeMaximum allowable stress = 150 MPa.

Case 1 - simply supportedPipe treated as simply supported (ie flexible joints at supports).

Saddle reaction Ps = 688 x 9.81 x 22.2

= 149834 Nk = 0.02-0.00012 x (120-90)

= 0.0164

Ï«L = (kPs) x loge (r )t2 t

= (0.0164 x 149834) x loge(381)144 12

= 58.8 MPa

Beam bending stress at supports = 0 MPaPoisson stress = 0 MPa(assuming flexible joints allow movement of pipes)

Therefore maximum saddle stress = 58.8 < 150 MPaNote: Bending stress at mid-span

«B mid-span = 1000wL2

8Z

= 1000 x 688 x 9.81 x 22.22

8 x 5219 x 103

= 79.7 MPa

Case 2 - Single welded lap joints at supportsCalculated span of pipe L2 = 24.8 m

Saddle reactionPs = 688 x 9.81 x 24.8

= 167380 N k = 0.0164

Ï«L = (0.0164 x 167380) x loge(381)144 12

= 65.9 MPa

Beam bending stress at support point

«B = 1000wL2

10Z

= 1000 x 688 x 9.81 x 24.82

10 x 5219 x 103

= 79.5 MPa

Poisson stress§«h = 0.27 x «H

= 0.27 x 95.3 = 25.7 MPa

ÏTotal stress«TOT = 65.9+79.5+25.7

=171.1>150 MPa

Hence pipe span will have to be reduced. Try span of 22 m

Saddle reaction = 688 x 9.81 x 22 = 1484800 N

Ï«L = (0.0164 x 148480) x loge(381)144 12

= 58.5 MPa

«B = 1000 x 688 x 9.81 x 222

10 x 5219 x 103

= 62.6 MPa

§«h = 25.7 MPa

«TOT = 58.5 + 62.6 + 25.7 = 146.8 < 150 MPa

Therefore adopt 22m span for this case.

Case 3 - fully welded joints at supportsL1 = 27.2m

Saddle reaction

Ps = 688 x 9.81 x 27.2

= 183580 N

k = 0.0164

Ï«L = (0.0164 x 183580) x loge(381)144 12

= 72.3 MPa

S E C T I O N 1 4 | 109

Beam bending stress at support«B = 1000wL2

12 Z

= 1000 x 688 x 9.81 x 27.22

12 x 5219 x 103

= 79.7 MPa

Poisson stress = 25.7 (as before) MPaÏTotal stress «TOT = 72.3 + 79.7 +25.7

= 177.7 > 150 Mpa

Therefore reduce span. Try a length of 23m

Saddle reaction = 688 x 9.81 x 23 = 155230 N Ï«L = (0.0164 x 155230) x loge(381)

144 12= 61.1 MPa

«B = 1000 x 688x 9.81 x 232

12 x 5219 x 103

= 57 MPa§«h = 25.7 MPa«TOT = 61.1 + 57 + 25.7 = 143.8 < 150 Mpa

Therefore make span 23 m long for this case.

S E C T I O N 1 4


110 | S E C T I O N 1 4

Table 14.1 - Maximum span for Simply Supported MSCL pipe (bending stresses only).

Section Dimensions Component Masses Total Section Safe SpanSteel Shell CML SK Steel CML Water Mass Modulus Fully Single Simply

Welded Lap Weld Supported

OD t T ts M1 M2 M3 MTOT Z L1 L2 L3

mm mm mm mm kg/m kg/m kg/m kg/m mm3 m m m114 4.8 9 1.6 12.9 6.5 5.9 25.3 43145 12.9 11.8 10.2168 4.5 9 1.6 18.1 10.2 15.6 44.0 92019 14.3 13.1 11.3168 5 9 1.6 20.1 10.1 15.4 45.6 101326 14.7 13.5 11.7190 4.5 9 1.6 20.6 11.7 20.9 53.1 118805 14.8 13.5 11.7190 5 9 1.6 22.8 11.6 20.6 5.05 130960 15.3 13.9 12.1

219 5 9 1.6 26.4 13.6 28.7 68.6 175830 15.8 14.5 12.5240 5 9 1.6 29.0 15.0 35.3 79.3 212446 16.2 14.8 12.8257 5 9 1.6 31.1 16.2 41.2 88.4 244624 16.5 15.0 13.0273 5 9 1.6 33.0 17.3 47.1 97.4 276983 16.7 15.2 13.2290 5 12 1.8 35.1 24.3 51.5 110.9 313567 16.6 15.2 13.2

305 5 12 1.8 37.0 25.6 57.7 120.3 347732 16.8 15.4 13.3324 5 12 1.8 39.3 27.4 66.1 132.7 393544 17.0 15.5 13.5324 6 12 1.8 47.1 27.2 65.1 139.4 467877 18.1 16.5 14.3337 5 12 1.8 40.9 28.5 72.1 141.6 426523 17.2 15.7 13.6337 6 12 1.8 49.0 28.4 71.2 148.5 507268 18.3 16.7 14.5356 5 12 1.8 43.3 30.3 81.4 155.0 477111 17.4 15.8 13.7356 6 12 1.8 51.8 30.1 80.4 162.3 567705 18.5 16.9 14.6

406 5 12 1.8 49.4 34.8 108.7 192.9 623784 17.8 16.2 14.1406 6 12 1.8 59.2 34.6 107.5 201.3 743007 19.0 17.3 15.0419 5 12 1.8 51.0 36.0 116.4 203.4 665136 17.9 16.3 14.1419 6 12 1.8 61.1 35.8 115.2 212.1 792445 19.1 17.5 15.1457 5 12 1.8 55.7 39.4 140.5 235.7 793619 18.2 16.6 14.4457 6 12 1.8 66.7 39.2 139.2 245.2 946088 19.4 17.7 15.4457 8 12 1.8 88.6 38.9 136.6 264.0 1244917 21.5 19.6 17.0457 10 12 1.8 110.2 38.5 134.0 282.7 1535725 23.1 21.0 18.2

502 5 12 1.8 61.3 43.5 172.0 276.8 960438 18.4 16.8 14.6502 6 12 1.8 73.4 43.3 170.6 287.2 1145634 19.8 18.0 15.6502 8 12 1.8 97.5 42.9 167.6 308.0 1509284 21.9 20.0 17.3508 5 12 1.8 62.0 44.0 176.5 282.5 983882 18.5 16.9 14.6508 6 12 1.8 74.3 43.9 175.0 293.1 1173682 19.8 18.1 15.6508 8 12 1.8 98.6 43.5 172.0 314.1 1546455 21.9 20.0 17.4508 10 12 1.8 122.8 43.1 169.1 335.0 1910246 23.6 21.6 18.7559 5 12 2 68.3 48.7 216.5 333.4 1194573 18.7 17.1 14.8559 6 12 2 81.8 48.5 214.8 345.1 1425791 20.1 18.4 15.9559 8 12 2 108.7 48.1 211.6 368.4 1880678 22.4 20.4 17.7559 10 12 2 135.4 47.7 208.3 391.4 2325622 24.1 22.0 19.1

610 5 12 2 74.6 53.3 260.6 388.4 1425692 19.0 17.3 15.0610 6 12 2 89.4 53.1 258.8 401.2 1702413 20.4 18.6 16.1610 8 12 2 118.8 52.7 255.2 426.7 2247585 22.7 20.7 17.9

S E C T I O N 1 4 | 111




mm mm mm mm kg/m kg/m kg/m kg/m mm3 m m m610 10 12 2 148.0 52.4 251.6 451.9 2781855 24.5 22.4 19.4648 5 12 2 79.3 56.7 296.1 432.1 1611180 19.1 17.4 15.1648 6 12 2 95.0 56.5 294.2 445.7 1924461 20.6 18.8 16.3648 8 12 2 126.3 56.2 290.3 472.8 2542217 22.9 20.9 18.1648 10 12 2 157.3 55.8 286.5 499.7 3148354 24.8 22.7 19.6660 5 12 2 80.8 57.8 307.8 446.3 1672111 19.1 17.5 15.1660 6 12 2 96.8 57.6 305.8 460.2 1997409 20.6 18.8 16.3660 8 12 2 128.6 57.3 301.9 487.8 2639029 23.0 21.0 18.2660 10 12 2 160.3 56.9 298.0 515.2 3268803 24.9 22.7 19.7

700 5 12 2 85.7 61.4 348.4 495.5 1883383 19.3 17.6 15.2700 6 12 2 102.7 61.2 346.3 510.2 2250370 20.8 19.0 16.4700 8 12 2 136.5 60.9 342.1 539.5 2974803 23.2 21.2 18.4700 10 12 2 170.2 60.5 338.0 568.7 3686637 25.2 23.0 19.9711 5 12 2 87.0 62.4 360.0 509.4 1943686 19.3 17.6 15.3711 6 12 2 104.3 62.2 357.8 524.4 2322578 20.8 19.0 16.5711 8 12 2 138.7 61.9 353.6 554.2 3070665 23.3 21.3 18.4711 10 12 2 172.9 61.5 349.4 583.8 3805947 25.3 23.1 20.0762 5 12 2 93.3 67.0 416.2 576.6 2235690 19.5 17.8 15.4762 6 12 2 111.9 66.9 414.0 592.7 2672261 21.0 19.2 16.6762 8 12 2 148.7 66.5 409.4 624.7 3534987 23.5 21.5 18.6762 10 12 2 185.4 66.1 404.9 656.5 4383946 25.6 23.3 20.2

800 5 16 2.3 98.0 93.5 451.3 642.8 2466542 19.4 17.7 15.3800 6 16 2.3 117.5 93.3 448.9 659.6 2948747 20.9 19.1 16.5800 8 16 2.3 156.2 92.8 444.1 693.2 3902202 23.5 21.4 18.6800 10 16 2.3 194.8 92.3 439.4 726.5 4841175 25.5 23.3 20.2813 5 16 2.3 99.6 95.1 466.9 661.6 2548121 19.4 17.7 15.3813 6 16 2.3 119.4 94.8 464.5 678.7 3046458 21.0 19.1 16.6813 8 16 2.3 158.8 94.3 459.6 712.8 4031994 23.5 21.5 18.6813 10 16 2.3 198.0 93.9 454.8 746.7 5002802 25.6 23.4 20.2889 5 16 2.3 109.0 104.3 563.5 776.7 3051608 19.6 17.9 15.5889 6 16 2.3 130.6 104.0 560.8 795.5 3649569 21.2 19.3 16.8889 8 16 2.3 173.8 103.5 555.5 832.8 4833277 23.8 21.8 18.8889 10 16 2.3 216.8 103.0 550.2 870 6000825 26.0 23.7 20.5895 5 16 2.3 109.7 105.0 571.5 786.2 3093290 19.6 17.9 15.5895 6 16 2.3 131.5 104.7 568.8 805.1 3699501 21.2 19.4 16.8895 8 16 2.3 175.0 104.3 563.5 842.7 4899627 23.9 21.8 18.9895 10 16 2.3 218.2 103.8 558.1 880.2 6083480 26.0 23.7 20.6

914 6 16 2.3 134.3 107.0 594.5 835.8 3859859 21.3 19.4 16.8914 8 16 2.3 178.7 106.5 589.0 874.3 5112721 23.9 21.8 18.9914 10 16 2.3 222.9 106.1 583.6 912.6 6348953 26.1 23.8 20.6914 12 16 2.3 266.9 105.6 578.2 950.7 7568702 27.9 25.5 22.1960 6 16 2.3 141.2 112.6 659.0 912.7 4262184 21.4 19.5 16.9

S E C T I O N 1 4


112 | S E C T I O N 1 4




mm mm mm mm kg/m kg/m kg/m kg/m mm3 m m m960 8 16 2.3 187.8 112.1 653.3 953.2 5647421 24.1 22.0 19.0960 10 16 2.3 234.3 111.6 647.5 993.4 7015160 26.3 24.0 20.8960 12 16 2.3 280.5 111.1 641.8 1033.5 8365550 28.1 25.7 22.2972 6 16 2.3 142.9 114.0 676.4 933.3 4370418 21.4 19.5 16.9972 8 16 2.3 190.2 113.6 670.6 974.3 5791281 24.1 22.0 19.1972 10 16 2.3 237.2 113.1 664.8 1015.1 7194420 26.3 24.0 20.8972 12 16 2.3 284.1 112.6 659.0 1055.7 8579983 28.2 25.7 22.3

1016 6 16 2.3 149.4 119.4 742.0 1010.8 4778888 21.5 19.6 17.01016 8 16 2.3 198.9 118.9 735.9 1053.7 6334249 24.3 22.1 19.21016 10 16 2.3 248.1 118.4 729.9 1096.3 7871056 26.5 24.2 21.01016 12 16 2.3 297.1 117.9 723.8 1138.8 9389460 28.4 25.9 22.51035 6 16 2.3 152.3 121.6 771.3 1045.2 4960914 21.6 19.7 17.01035 8 16 2.3 202.6 121.2 765.1 1088.9 6576233 24.3 22.2 19.21035 10 16 2.3 252.8 120.7 758.9 1132.4 8172642 26.6 24.3 21.01035 12 16 2.3 302.7 120.2 752.8 1175.7 9750288 28.5 26.0 22.51067 6 16 2.3 157.0 125.5 821.9 1104.4 5275174 21.6 19.7 17.11067 8 16 2.3 208.9 125.0 815.5 1149.5 6994040 24.4 22.3 19.31067 10 16 2.3 260.7 124.5 809.1 1194.3 8693393 26.7 24.4 21.11067 12 16 2.3 312.2 124.1 802.8 1239.0 10373380 28.6 26.1 22.61086 8 16 2.3 212.7 127.3 846.2 1186.2 7248201 24.5 22.3 19.31086 10 16 2.3 265.3 126.8 839.7 1231.9 9010199 26.8 24.4 21.21086 12 16 2.3 317.8 126.4 833.2 1277.4 10752473 28.7 26.2 22.7

1124 8 16 2.3 220.2 131.9 909.3 1261.4 7770133 24.6 22.4 19.41124 10 16 2.3 274.7 131.4 902.6 1308.7 9660823 26.9 24.5 21.21124 12 16 2.3 329.1 130.9 895.8 1355.9 11531074 28.8 26.3 22.81145 8 16 2.3 224.3 134.5 945.2 1303.9 8066354 24.6 22.5 19.51145 10 16 2.3 279.9 134.0 938.3 1352.1 10030110 26.9 24.6 21.31145 12 16 2.3 335.3 133.5 931.4 1400.2 11973030 28.9 26.4 22.9

1200 8 16 2.3 235.2 141.1 1042.3 1418.6 8868434 24.7 22.6 19.61200 10 16 2.3 293.5 140.6 1035.1 1469.1 11030119 27.1 24.7 21.41200 12 16 2.3 351.6 140.1 1027.9 1519.6 13169931 29.1 26.6 23.01219 8 16 2.3 238.9 143.4 1077.0 1459.3 9154351 24.8 22.6 19.61219 10 16 2.3 298.1 142.9 1069.6 1510.7 11386619 27.2 24.8 21.51219 12 16 2.3 357.2 142.4 1062.3 1561.9 13596657 29.2 26.6 23.11283 8 19 2.3 251.5 179.0 1186.3 1616.9 10150814 24.8 22.6 19.61283 10 19 2.3 313.9 178.5 1178.6 1671.0 12629182 27.2 24.8 21.51283 12 19 2.3 376.1 177.9 1170.9 1724.9 15084115 29.3 26.7 23.11290 8 19 2.3 252.9 180.0 1199.8 1632.8 10262925 24.8 22.6 19.61290 10 19 2.3 315.6 179.5 1192.1 1687.2 12768991 27.2 24.8 21.51290 12 19 2.3 378.2 178.9 1184.4 1741.4 15251490 29.3 26.7 23.1

1404 8 19 2.3 275.4 196.4 1431.4 1903.2 12175401 25 22.8 19.8

S E C T I O N 1 4 | 113




mm mm mm mm kg/m kg/m kg/m kg/m mm3 m m m1404 10 19 2.3 343.8 195.8 1422.9 1962.5 15154215 27.5 25.1 21.71404 12 19 2.3 411.9 195.2 1414.5 2021.6 18107313 29.6 27.0 23.41416 8 19 2.3 277.8 198.1 1456.9 1932.8 12386215 25.0 22.9 19.81416 10 19 2.3 346.7 197.5 1448.4 1992.7 15417166 27.5 25.1 21.81416 12 19 2.3 415.5 197.0 1439.9 2052.3 18422176 29.6 27.1 23.41422 8 19 2.3 279.0 199.0 1469.8 1947.7 12492300 25.1 22.9 19.81422 10 19 2.3 348.2 198.4 1461.2 2007.8 15549490 27.5 25.1 21.81422 12 19 2.3 417.2 197.8 1452.7 2067.7 18580625 29.7 27.1 23.41440 8 19 2.3 282.5 201.5 1508.7 1992.8 12813270 25.1 22.9 19.81440 10 19 2.3 352.6 201.0 1500.1 2053.7 15949855 27.6 25.2 21.81440 12 19 2.3 422.6 200.4 1491.4 2114.4 19060045 29.7 27.1 23.51451 10 19 2.3 355.4 202.6 1524.0 2081.9 16197028 27.6 25.2 21.81451 12 19 2.3 425.8 202.0 1515.3 2143.1 19356030 29.7 27.1 23.51451 16 19 2.3 566.2 200.8 1497.9 2264.9 25594824 33.3 30.4 26.3

1500 10 19 2.3 367.4 209.6 1633.1 2210.1 17321161 27.7 25.3 21.91500 12 19 2.3 440.3 209.0 1624.1 2273.4 20702219 29.9 27.3 23.61500 16 19 2.3 585.5 207.9 1606.1 2399.4 27382355 33.4 30.5 26.41575 10 19 2.3 385.9 220.3 1807.4 2413.7 19114814 27.8 25.4 22.01575 12 19 2.3 462.5 219.8 1797.9 2480.2 22850363 30.0 27.4 23.71575 16 19 2.3 615.1 218.6 1778.9 2612.7 30235238 33.7 30.7 26.6

1600 10 19 2.3 392.1 223.9 1867.5 2483.5 19732334 27.9 25.5 22.01600 12 19 2.3 469.9 223.4 1857.8 2551.1 23589973 30.1 27.5 23.81600 16 19 2.3 625.0 222.2 1838.5 2685.7 31217615 33.7 30.8 26.71626 10 19 2.3 398.5 227.7 1931.0 2557.2 20384968 27.9 25.5 22.11626 12 19 2.3 477.6 227.1 1921.2 2625.9 24371664 30.1 27.5 23.81626 16 19 2.3 635.2 225.9 1901.6 2762.7 32255950 33.8 30.9 26.7

1750 10 19 2.3 429.1 245.4 2248.5 2923.0 23643617 28.1 25.7 22.21750 12 19 2.3 514.3 244.9 2237.9 2997.0 28275032 30.4 27.7 24.01750 16 19 2.3 684.2 243.7 2216.7 3144.6 37441744 34.1 31.2 27.0

1829 10 19 2.3 448.6 256.8 2463.4 3168.7 25845646 28.3 25.8 22.31829 12 19 2.3 537.7 256.2 2452.2 3246.1 30912999 30.5 27.9 24.11829 16 19 2.3 715.3 255.1 2430.1 3400.5 40947123 34.3 31.3 27.1

1981 10 19 2.3 486.0 278.6 2904.3 3669.0 30358231 28.5 26.0 22.51981 12 19 2.3 582.7 278.0 2892.3 3752.9 36319506 30.8 28.1 24.31981 16 19 2.3 775.3 276.9 2868.2 3920.4 48132880 34.7 31.6 27.4

2159 10 19 2.3 529.9 304.1 3466.9 4301.0 36104047 28.7 26.2 22.72159 12 19 2.3 635.3 303.5 3453.7 4392.6 43204421 31.0 28.3 24.52159 16 19 2.3 845.5 302.4 3427.4 4575.4 57285927 35.0 32.0 27.7

S E C T I O N 1 4


AppurtenanceDesign

114

section15

116 | S E C T I O N 1 5

Figure 15.1 – Reinforcement of Openings

15.1 IntroductionTees, laterals and bifurcations provide a means of dividing or unitingflow in pipelines. These fittings do not have the same resistance tointernal pressure as straight pipe of a similar size.

Not all appurtenances need reinforcement, because the wallthickness used is generally thicker than that required for pressureconsiderations. However, if a pipe is operating at or near thedesign pressure the strength of the fitting should be checked andreinforced if necessary.

Generally, reinforcement is made available by the addition of alocalised thickening of the pipe, called a collar reinforcement.Other times a thicker wall pipe may be used, called a wrapperplate design, or in the case of bifurcations and tees, crotch platesmay be necessary.

This section only deals with the design of reinforcements of nozzleshaving a d/D ratio F 0.7 and a PDV value F 6000. For ratios of d/Dgreater than 0.7, refer to AWWA M11 – Manual of Water SupplyPractices - Steel Pipe – A guide for Design and Installation.

15.2 Design methodThe method generally adopted for reinforcements of nozzles is the“Area - Replacement” method. Here the area of the wall removedfrom the pipe so as to attach the fitting is replaced by means of acollar, welded to the outside surface of the pipe. The area removedis based on the maximum width of the opening measured along thelongitudinal axis of the pipe, multiplied by the pipe wall pressurethickness required. Any excess area available in the pipe wall aswell as any excess area available in the branch wall for a distance of

2.5ty normal to the main pipe surface but measured from thesurface of the reinforcing collar, must be taken into consideration.

Consider the following:

PDV = 5.7087Pd2

F 6000(D sin2 £ )

P = design pressure MPaD = outside diameter of the pipe mmd = outside diameter of the branch mm£ = angle of the nozzle degreesTy = main pipe wall thickness mmty = branch pipe wall thickness mmM = factor (see Table 15.1)

Theoretical wall thickness of the main pipe:

Tr = PD mm2«all

Theoretical wall thickness of the branch:

tr = Pd mm2«all

Area removed:

AR = M Tr (d-2ty ) mm2

sin£

Area available as excess

AA = (d-2ty) (Ty –Tr ) +5ty ( ty - tr ) mm2

sin£

Reinforcement areaAW = AR – AA mm2

= 2wT

d /SIN £

£

S E C T I O N 1 5 | 117

Minimum reinforcement thickness T

w = d mm2 sin£

T = AW = AWsin£2w d mm

The overall width W, of the collar should not be less than 1.67d/sin£and should not exceed 2.0d/sin£, i.e the collar edge width w, shouldbe within 0.333d/sin£ F w F 0.5d/sin£. Collar edge width in thecircumferential direction should not be less than the longitudinal edgewidth. Nozzles should not be placed on the pipe weld seams.

In Fig. 15.1, the area Ty (d-2ty) / sin£ represents the section of themain pipe removed for the branch opening. The hoop tension dueto pressure that would be taken by the area removed must becarried by the total areas represented by 2wT and 5ty (ty – tr ), or2.5ty (ty – tr ) on each side of the branch.

Table 15.1- PDV values and M factors for d/D ratios

15.3 Example of a calculation fordetermination of reinforcement size.Consider a pipe having a diameter of 914mm and a wall thickness of6 mm with a design pressure of 2 MPa, with a branch 610mmdiameter by 5mm wall thickness set at an angle of 75°. Pipe materialhas a MYS of 300 MPa and the allowable stress «all = 0.7 MYS

PDV = 5.7087 x 2 x 6102 / (914 sin2 75 )= 4982 < 6000

M factor from Table 16.1 = 0.00025 x 4982 = 1.25( Note: if £ = 60°, PDV = 6224 > 6000. Refer to AWWA – M11 )

«H = 2 x 914 / (2 x 6 ) = 152.3 MPa«all = 0.72 x 300 = 216.0 MPad/D = 610/914 = 0.67 < 0.7 ( O.K.)Ty = 6 mmty = 5 mmTr = (2 x 914)/(2 x 216) = 4.23 mm tr = (2 x 610)/(2 x 216) = 2.82 mm

Theoretical reinforcement area ( Area removed )AR = 1.25 x 4.23 x (610-2 x 5)/ sin75 = 3284 mm2

Area available as excessAA = (610-10)/sin75 x (6-4.23)+5 x 5(5-2.82)

= 1110 mm2

Reinforcement areaAW = 3284-1110 = 2174 mm2

Minimum reinforcement thickness TT = 2174 sin 75 / 610 = 3.44 say 4.0 mm

Reinforcement widthw = 2174/(2 x 4) = 271.8 mm

Minimum allowable widthwmin = d/(3sin£) = 610 / ( 3 x sin 75 ) = 211 mm, therefore use 272 width

Overall reinforcement widthW = 2w + d / sin£ = 2 x 272+610/sin75 = 1176 mm from 4mm thick plate.

PDV d/D M factor

4000 – 6000 F 0.7 0.00025PDV

< 4000 F 0.7 1.0

S E C T I O N 1 5

Appurtenance Design

TypicalInstallationConditions

118

section16

120 | S E C T I O N 1 5

16.1 Trench conditionsThese installations are suitable for SINTAKOTE welded steelpipelines and SINTAJOINT rubber ring joint ( RRJ ) steel pipelinesas described.

The following terms and their definitions are referred to in thissection. See Figure 16.1.

Bedding - the zone between the foundation and the bottom of the pipe

Haunch support – the part of the side support below the spring line of the pipe

Side Support - the zone between the bottom and the top of the pipe

Overlay – the zone between the side support and either the trench fill or the embankment fill

Trench Fill – fill material placed over the overlay for the purpose offilling the trench

Trench widthThe trench width should be as narrow as practicable consistentwith the need to ensure:• Proper laying and jointing of the pipe• Application of joint wrapping if relevant• Where a change of direction is being made using the lateraldeflection permissible at the joints, the trench should besufficiently wide to allow the joint to be made in line and then thepipe laterally deflected• Where the virgin soil does not provide the pipe with the requiredside support, the trench must be wide enough to allow theselected back-fill to be placed and compacted in such a mannerwhich will adequately spread the load into the surrounding ground

Common size backhoe / excavator bucket widths are 300, 450,600, 750, 900, 1100 and 1200mm.

As a guide, the following trench minimum widths are reasonable:

OD + 400mm for pipe diameters ≤ 450mm

OD + 600mm for pipe diameters >450mm, ≤900mm

OD + 700mm for pipe diameters >900mm, ≤1500mm

0.25 x OD mm for pipe diameters >1500mm

Trench depthThe depth of the trench will depend on a number of factors apartfrom pipe diameter. Other considerations include:• External loadings. Pipes usually have a greater depth of coverwhen subject to vehicle loading

• Location of other services, particularly in urban areas• Future change in levels due to road re-grading or other civil works

The minimum depth of cover recommended is 0.6m provided noneof the other considerations require a greater depth. In rock, thetrench should be excavated to ensure that at least 50mm ofcompacted bedding is achieved under the pipe after it is bedded.

Where an unstable sub-grade condition unable to support the pipeis encountered, an additional depth should be excavated andbackfilled as discussed below.

Bedding Bedding provides support to the pipeline enabling it to withstandexternal loads. The higher the external loading (depth of trenchplus any vehicle loading) the greater the degree of carenecessary with the backfill in this zone. Any part of the trenchexcavated below grade unintentionally or because of rockyground should be backfilled to grade with a thoroughlycompacted approved material.

In the case of additional depth due to unstable sub-grade the extradepth should be backfilled with crushed stone or other suitablematerial to achieve a satisfactory trench bottom.

For open field loading where traffic and superimposed loading willbe low, the bedding angle (total depth of bedding) can be limitedto approximately 70°. For roadways or heavy traffic andsuperimposed loads total depth of compacted bedding may needto be increase to the spring line (centre line) of the pipe to increasethe bedding angle to 180°, maximise support and minimisedeflection. See Spangler & Handy (ref 3).

In order to prevent damage to SINTAKOTE a compacted zone of50 mm below the pipe should comprise non-cohesive native soil,imported fill or sand such that the maximum particle size does notexceed 13.2 mm.

SINTAJOINT ( RRJ ) pipelinesBellholes should be excavated in the foundation to prevent thesocket from bearing on the foundation.

SINTAKOTE welded joint pipelinesConstruction holes should be excavated at the joint to facilitatewelding and coating reinstatement. Bedding should then be restored.

Haunch support, side support and overlayIt is essential that backfill for haunch support, side support andoverlays be well compacted between the sides of the pipe and thetrench. Particular care should be taken in compacting the materialunder the haunches of the pipe.

The backfill should be built up in layers evenly on both sides of the

S E C T I O N 1 6 | 121

pipe. Whilst the depth of such layers should be established at thecommencement of the laying for any particular material to be used,it should not normally exceed 150 mm. Backfilling in layers shouldproceed until 150 mm above the top of the pipe or as otherwisespecified where vehicular traffic is encountered.

Backfill provides material to support the pipe and prevent sharpobjects imparting high loads onto the pipeline coating. The materialused should be non-cohesive native soil with no particles largerthan 25mm, or imported sand or gravel of nominal size not largerthan 20mm with the maximum size not to exceed 25mm.

When select backfill or bedding is used with pipes which are to becathodically protected, the material should not be too high inelectrical resistivity as this will reduce the effectiveness of theprotection. Generally, sand or native soil is suitable. Stone andgravel can be too high in resistivity. Hence a graded mix of sandand gravel should be used on cathodically protected lines whereimported backfill is required.

Compaction should achieve the effective combined soil modulus E’.

Non-cohesive soilsCohesionless soils are often specified for bedding and side supportareas of buried conduits.

They offer the advantages of

• ease of placement and handling• minimum compactive effort• free draining behaviour• minimum settlement• non shear stress memory• maximum density over a wide moisture content range• high shear strength

• anchorage friction

For situations where trench water flow is possible, cross trenchdams keyed into trench walls should be constructed to preventerosion of backfill and bedding.

Trench fillThe trench can then be topped up with convenient fill. Wherenecessary it should be compacted to achieve the appropriaterelative density for pavement support. The extent of compactiondepends on the allowable future surface settlement. Under roads,pavements and in certain other areas the load bearing capacity ofthe ground surface is important and fill must be compacted inlayers all the way to the surface.

Where the trench is across open land the compaction requirementsare not normally so important and the surface can usually be builtup to a degree to allow for some future settlement.

The material used would normally be the excavated trench materialbut where a high degree of compaction is needed in poor naturalground, imported material may be required.

16.2 CompactionCompaction increases the density of the soil resulting in greaterbearing capacity, stability and reduced permeability and settlement.Void space is reduced and interparticle contact is increasedresulting in higher internal friction.

Generally, non cohesive soils require less compactive effort toachieve a given density as the interparticle cohesive forces to beovercome in rearranging the soil are a minimum.

Vibratory compaction uses equipment which incorporates vibration,normally by means of a rotating eccentric weight. The vibration

S E C T I O N 1 6

Typical Installation Conditions

Figure 16.1 - Definition of terms

Trench wall

Embedmentzone

Springline of pipe

Finished surface

Trench Embankment

Trench fill

Overlay

Sidesupport

Bedding

Haunchsupport

Haunchsupport

Embedmentzone

Springline ofpipe

Top of embankment(finished surface)Embankment fill

CLCL

S E C T I O N 1 6 | 123

jostles adjacent particles and allows their relative movement tosettle together in a denser state.

The three main factors to be considered in compaction are:• soil type• moisture content• compaction method and energy input

Soil classificationA commonly referred system of soil classification is the United Soil Classification System (USCS). Soils are categorised by this system in 15 groups identified by name and letter symbols.(ref Table 13.2)

GradationThe gradation of a soil is a measure of the size and distribution ofthe constituent particles. This is assessed by sieving the samplethrough a series of screens of increasing fineness. The retainedmaterial on each screen is expressed as a percentage of totalsample weight. These figures, when plotted on a graph show thegradation of the material. See Figure 16.2.

A well graded material covers a wide range of particles filled bysmaller ones. Higher densities are more easily achieved with wellgraded materials than uniformly graded materials.

Density index - non cohesive soilsDensity index ID is a measure of compaction used for non cohesive(low fines) soils, and is specified in AS 1289.5.6.1 as:

ID = ~max (~ – ~min ) x 100%~ (~max – ~ min )

where ~max = maximum dry soil density kN/m3

~min = minimum dry soil density kN/m3

~ = measured dry soil density kN/m3

= 100Þ(100 + wt)

Þ = measured wet soil density kN/m3

wt = measured soil moisture content %

~min is determined by drying and pulverising the soil to a single grainsize and pouring with minimum disturbance into a container of aknown volume. The sample is then weighed and ~min determined.

~max is determined after compaction with a drop hammer, tamperor vibrator.

Dry density ratio - cohesive soilsDry density ratio (RD) is a measure of compaction used forcohesive soils and is specified in AS 1289.5.4.1 as:

RD = 100~~

r

Where:~ = measured dry soil density kN/m3

~r = maximum dry density (adjusted for oversize material,

where applicable) kN/m3

as assigned or determined in the compaction test.

Compaction equipmentThe most common forms of compaction equipment used inpipeline construction are vibratory plate compactors and vibratorytampers. Their use depends very much on the surface loads to becarried by the installation. This load carrying capacity depends onthe structural stiffness of the pipe and the degree of soil beddingand side support compaction achieved.

Very dry sand and gravel can be vibrated into place at a density ofover 90% providing it contains little or no silt.

Sluicing and dumpingWhere the material is of a granular nature and drains quickly, analternative to using compacting equipment is to flood the backfillwith water. Using this method with coarse sand a 60% relativedensity can be achieved, whilst with fine sand a 50% relativedensity should be attained.

100

90

80

70

60

50

40

30

20

Per

cent

pas

sing

0.0001 0.001 0.01 0.1 1 10 100

Particle size in mm

Clay Silt Sand Gravel Cobbles

Silt

Clay

Uniformlygraded

sand

Wellgradedsand

Road basematerial

U.S. standard sieves40 10 1.1/2"

200 100 50 30 16 8 4 3/8"3/4" 3" 6" 12"

Figure 16.2 - Sieve analysis

S E C T I O N 1 6


124 | S E C T I O N 1 6

Clean selected aggregate will usually achieve 60% relative densityor better by simply dumping around the pipe.

16.3 Backfill prior to hydrostatic field testWhen laying pipelines it is normal practice to place some backfill on the pipes to prevent movement during hydrostatic testing.

In the case of flexible jointed pipelines such fill is essential toprevent any joint movement during the subsequent operations.

Where the pipeline has welded joints the fill is usually placed on the barrel portion of the pipe only, leaving the joints exposed forexamination during the hydrostatic test.

In a rubber ring joint pipeline, sufficient fill should be placed oneach pipe following its installation to prevent joint movement duringpositioning of adjacent pipes.

There is no need to leave flexible joints exposed provided the layingis carried out strictly in accordance with the recommended layingpractice. Refer to Tyco Water Steel Pipelines Installation andHandling Manual.

Measurement of soil compactionStandard tests are available for determining the density ofcompacted soil. These tests are outlined in AS 1289 – E3. An experienced engineer can usually tell the density from hisfootmarks on the soil. If he has to back-kick the soil with the cornerof his heel to leave an impression then the density is probablygreater than 95%. A heel corner impression while walking probablyindicates a soil density of 90%. A full heel imprint may indicate adensity above 80% whilst a full footprint would suggest a density of only 70%.

16.4 Hydrostatic field test.A pipeline is subjected to a hydrostatic field test primarily to checkthat all joints are watertight. At the same time the test checks theintegrity of all fittings and appurtenances, as well as constructionwork such as anchorages.

Where concrete anchor blocks are installed, allow at least 7 daysfor the concrete to cure before any test is carried out.

If the pipeline section to be tested is not provided with valves thenthe ends must be fitted with bulkheads. Such bulkheads musthave attachments to allow passage of the incoming water andoutgoing air.

Hydraulic jacks may be inserted between the temporary anchorsand sealed ends in order to take up any horizontal movement of the

temporary anchors. All outlets should be plugged prior to testing.

Air valves should be properly located and checked to ensure theyare operational. If permanent air vents are not provided at all highpoints, the contractor should install corporation cocks at all suchpoints to expel air during filling of the line.

Filling prior to tests.Cement mortar lined pipe should be completely filled with water andallowed to stand for 24 hours or longer to permit maximumabsorption of water by the lining, although experience has shownthat 4-5 days soaking is more beneficial in reducing this effect afterfilling. Lines should be flushed at hydrants, scours and dead ends.

Filling should be done slowly to prevent water hammer and toensure all the air is allowed to escape. Additional water should beadded to replace that absorbed by the cement mortar lining. It isgood practise to do a final manual bleed of the line prior to startingthe pressure test.

Test measurementTest pressure should be measured at the lowest point of thesection under test, or a static head allowance between the lowestpoint and the point of measurement should be made to ensure thatthe required test pressure is not exceeded.

The field test pressure specified must accommodate the ratedpressure of fittings and appurtenances.

Test method• It is recommended that initially the field test be carried out on asmall section (200m) of the pipeline laid first to confirm that layingpractises are effective.

• Pressure testing should not be carried out during wet weather.

• Pump in water until the test pressure is reached. The field testpressure is normally specified in the relevant contract documents.The test pressure should lie between the maximum operatingpressure of the pipeline, and no more than 125% of the maximumoperating pressure. It is good practise to allow the system time tostabilise at the test pressure before starting the test. This periodcan be utilised to check and tighten bolted fittings, flanges etc. thatshow signs of leaking.

• The test pressure should be maintained for at least 2 hours.

• During pressure testing all field joints which have not beenbackfilled shall be clean, dry and accessible for inspection.

• If the pressure has dropped at the end of the test period thequantity of water(make up volume) required to increase thepressure to the original test pressure should be established.

S E C T I O N 1 6 | 125

• The test should be repeated a number of times with any makeup volume being measured.

• It is normal for a pressure drop to occur due to;- entrapped air going into solution- water being absorbed into the cement mortar lining- weeping at valve seats, fittings and appurtenances- movement of pipe under pressure- changes in pipe temperature

• A generally accepted make-up volume rate is;

Q = 0.00014 DLH

Where Q = make up water rate litres / hour

D = pipe diameter mm

L = test pipeline length km

H = mean test head m

• If the specified make-up volume is exceeded;- ensure all air has been expelled- check all valves for closure and sealing- check all mechanical joints, gibaults and flanges. Bolts should beuniformly tight and full sealing achieved.

• If subsequent testing results in unacceptable make up volume,the ground above the pipeline should be inspected for signs ofobvious leakage. A bar probe may be be used to detect thelocation of any leaks. If none are apparent the line should be testedin halves with the failing section being subsequently halved untilthe leak is located.

• The pressure test shall be considered satisfactory if:- there is no failure of any anchor block, pipe, fitting, valve, joint orany other pipeline or service component- there is no visible leakage, and- the maximum acceptable loss rate is not exceeded

After test• It is important to ensure that proper arrangements are madefor the disposal of water from the pipeline after the test, and thatall consents which may be required from land owners andoccupiers, and from river drainage and water authorities havebeen obtained.

16.5 Pneumatic test of welded joints.Welded joint pipe (Spherical Slip-in and Ball and Socket joints) can betested for integrity of the field welding by an air pressure test.

This can only be done however if an external and internal weldare executed. An air hole must also be drilled into the sealed

annulus between the welds and tapped for air nozzleattachments. See Fig 6.3.

The weld is then daubed with a soap solution and the annuluspressurised to around 100kPa. The welds are then examinedfor bubbles of escaping air and rectified if necessary.

For large pipelines this test can assure the integrity asconstruction progresses eliminating the time and cost of amajor hydrostatic field test.

16.6 Backfill following hydrostatic field testAfter a section of a pipeline has passed the field pressure test to the satisfaction of the Supervising Engineer,the trench should be completely backfilled as soon as possible.

In badly drained ground or where heavy rain is expected,finished sections should not be left unfilled as there is a riskthe pipeline could be moved by floatation. See Table 5.2 forsubmerged weights of pipelines and Section 5.5.

16.7 Commissioning of water pipelines.Prior to hydrostatic testing care must be taken to ensureremoval of any solid material from the inside of the pipeline including rubbish, dirt, welding stubs and otherforeign matter.

This may be achieved by placing a swab or pig through the line or in the case of larger diameter pipes, by operators travelling through the line.

Only soft foam swabs (with no scouring pad attachments)should be used on seal coated pipelines.

A pipeline which will carry potable water should be sterilised with chlorinated water in accordance with the Water Agency’s requirements.

After standing for the prescribed period the water should be tested for residual chlorine to ensure sterilisationhas been achieved. Potable water may then be used to replace the chlorinated water. The pipeline is not to be put into service until bacteriological tests of waterdelivered at the end of the pipeline show that a satisfactorypotable standard has been attained.

Note that exit water may not be suitable for disposal to drains.

S E C T I O N 1 6


Appendices

126

appendix ABCD&E

128 | A P P E N D I X

Symbol Reference Unit| thermal coefficient of linear expansion of steel 12 x 10-6 mm/mm/°C| impact factor for live loads beam deflection mmßb predicted bending strain ßb all allowable bending strain£ angular deflection at pipe joint or at mitre cut or pipe bend degrees £ angle of nozzle to main pipe degrees £s saddle angle degrees~ unit weight of trench or embankment fill kN/m3

~ measured dry soil density kN/m3

~L assessed unit weight of liquid external to pipe kN/m3

~sub submerged unit weight of trench or embankment fill kN/m3

~min minimum dry soil density kN/m3

~max maximum dry soil density kN/m3

~r maximum soil dry density assigned/determined in compaction test kN/m3

¢ factor of safety for combined external load and internal pressure¢b factor of safety for ring bending strain ¢p factor of safety for internal pressureµ soil/pipe surface friction factor µ dynamic viscosity of water kg/ms § kinematic viscosity of water ( 0.11425 x 10-5 at 15°C ) m2 /s § Poisson’s ratio ( 0.27 for steel ) ª measured wet soil density kg/m3

ª s specific gravity of soil particle ( = 2.65 or determined value) kg/m3

«b bending stress at point MPa«h hoop stress MPa«all allowable hoop stress MPa«L saddle stress MPa«T temperature stress MPa«TOT total stress MPa¡ Leonhardt correction factorS pipe deflection m or mmSf design factorSh head rise above normal operating head mSp pressure rise above operating pressure MPaSy predicted vertical deflection of pipe in ground mSy all allowable vertical deflection of pipe in ground mST change in temperature °C a pressure wave velocity m/sa centre line length on bend mitre mmA cross area of pipe based on OD m2

AA area available as excess mm2

AR area removed mm2

AW reinforcement area mm2

bedding the layer of material directly under the pipe

A P P E N D I X A

Glossary

A P P E N D I X | 129

backfill the material at the sides and the set cover layer above and in contact with the pipeB&S ball and socket joint B trench width at pipe crown mC the element carbonCE carbon equivalentCML cement mortar liningCbb headloss coefficient factor for bendsCu the element copperCP cathodic protectionCr the element chromiumcover the depth of material H, from pipe crown to surface level md pipe inside diameter m or mmd branch outside diameter m or mm D, De ,Do pipe outside diameter m or mmDm pipe mean diameter (D-t) m or mmDB deformed pipe diameter m or mmD/t outside diameter to pipe wall thickness ratioDCF discounted cash flowDN nominal diameter m E’ effective combined soil modulus MPaE’e embedment soil modulus MPaE’n native soil modulus MPaE modulus of elasticity for the steel or composite steel-cement mortar liningEst Young’s modulus for steel 207000 MpaEcl Young’s modulus for cement mortar lining 21000 MpaFBPE fusion bonded polyethyleneFS factor of safetyG gradientg acceleration due to gravity 9.81 m/s2

H height of ground surface above pipe mH head after valve operation mHo head under constant flow condition mHw height of water surface above the top of the pipe mHL head loss in meters head of water mHGL hydraulic grade lineI second moment of area of the pipe wall per unit length mm4 /mm I elastic moment of inertia of the pipe mm4

ID inside diameter of pipe mmID Density index of non – cohesive soil %k saddle factor K bedding constantk thermal conductivity of steel 47 W/(m °C)k linear measure of bore roughness for the Colebrook-White formula mKL minor loss coefficientKLE minor loss coefficient

A P P E N D I X A

Glossary

130 | A P P E N D I X

KL1 minor loss coefficientKL2 minor loss coefficientL length dimension or length of pipeline m or mmL pipe span as a beam m or mm L1 length of the base of the live load distribution measured perpendicular to the direction

of travel of the vehicle at the top of the pipe mL2 length of the base of the live load distribution measured parallel to the direction of

travel of the vehicle at the top of the pipe m M factor for design of off-takesM1 unit mass of the steel shell kg/mM2 unit mass of the cement mortar lining kg/mM3 unit mass of Sintakote kg/m MA bending moment at point A NmMB bending moment at point B NmMC bending moment at point C NmMn the element manganeseMo the element molybdenumMTOT total mass of water filled pipe kg/mMW unit mass of water in pipe kg/m MSCL mild steel cement linedMTP manufacture test pressure MPaMYS minimum yield strength MPaNi the element nickel NPV nett present valuen number of yearsn number of individual mitres or a ratio in Allievi’s equationOD outside diameter mm P live wheel load, ∑P is the sum of the individual wheel loads kNP internal pressure MPaPt manufacture proof test or strength test pressure MPaPr field test pressure or rated pressure MPaPcr critical external pressure required to cause buckling kPaPW applied internal pressure MPaPWall allowable internal pressure MPaPs saddle reaction N PE plain ended pipePDV pressure/diameter valuePRV pressure reducing valve(s)pH -log (H+)qall allowable buckling pressure kPaqall1 allowable buckling pressure based on pipe alone kPaqall2 allowable buckling pressure based on pipe/embedment interaction kPaqv internal vacuum kPaQ flow rate or discharge l/s or m3/sR radius of bend or outside diameter radius of pipe m or mmRe resultant thrust at pipe bend kN

A P P E N D I X A

Glossary

A P P E N D I X | 131

R Reynolds numberRD Dry density ratio of cohesive soil %RRJ rubber ring jointr outside radius of pipe mmre equivalent circular arc on composite mitres mm ri interest raterc re-rounding effectrm mean radius (= (D-t) / 2 ) mmSg hydraulic gradient m/mSr ring-bending stiffness as a function of radius N/m/mSD ring-bending stiffness as a function of diameter N/m/mSDcr critical ring buckling resistance due to out of roundness N/m/mSSJ spherical slip-in jointSK SINTAKOTESR sulphate resistant cementT cement mortar lining thickness mmT reinforcement collar minimum thickness mmTr reflection period s To time for valve opening or closing sTs static thrust at blank ends and junctions kNTQM total quality managementtrench fill the material placed over the backfillt steel wall thickness mmts thickness of Sintakote mmTy main pipe wall thickness mmty branch wall thickness mmTR theoretical main pipe wall thickness mmtR theoretical branch wall thickness mmteq transformed pipe wall thickness mmUV ultra violetu superimposed, uniformly distributed dead load at finished surface kPav flow velocity m/svo flow velocity under steady state conditions m/sV the element vanadiumw reinforcement collar edge width mmWd weight of backfill kN/mWw weight of water in pipe kN/mWp weight of pipe kN/m wg vertical design load pressure at top of pipe due to soil dead loads kPawgs design load due to superimposed dead load kPawq vertical design load due to surface applied live load kPawt measured soil moisture content %w unit weight of pipe (steel, lining and water) N/my pipe deflection as a beam mmZ elastic section modulus of pipe mm3

A P P E N D I X A

Glossary

132 | A P P E N D I X

Quantity Unit Conversion FactorLength 1in 25.4 mm

1ft 0.3048 m1yd 0.9144 m1 fathom 1.8288 m1 chain 20.1168 m1 mile 1.60934 km1 international nautical mile 1.852 km1 UK nautical mile 1.85318 km

Area 1in2 6.4516 cm2

1 ft2 0.092903 m2

1 yd2 0.836127 m2

Volume 1 UK minim 0.0591938 cm3

1 UK fluid drachm 3.55163 cm3

1UK fluid ounce 28.4131 cm3

1 US fluid ounce 29.5735 cm3

1 US liquid pint 473.176 cm3

1 US dry pint 550.610 cm3

1 Imperial pint 568.261 cm3

1 UK gallon 4.54609 dm3

1 US gallon 3.78541 dm3

1 in3 16.3871 cm3

1 ft3 0.0293168 m3

1 yd3 0.764555 m3

2nd Moment of Area 1 in4 41.6231 cm4

Moment of Inertia 1 lb ft2 0.0421401 kg m2

1 slug ft2 1.35582 kg m2

Mass 1 grain 64.7989 mg1 dram (avoir.) 0.00177185 kg1 drachm (apoth.) 0.00388793 kg1 ounce (troy or apoth.) 0.0311035 kg1 oz (avoir.) 28.3495 g1 lb 0.45359237 kg1 slug 14.5939 kg1 sh cwt (US hundredweight) 45.3592 kg1 cwt (UK hundredweight) 50.8023 kg1 UK ton 1016.05 kg1 short ton 907.185 kg

Mass per Unit Length 1 lb/yd 0.496055 kg/m1 UK ton/mile 0.631342 kg/m1 UK ton/1000yd 1.11116 kg/m1 oz/in 1.11612 kg/m1 lb/in 1.48816 kg/m1 lb/in 17.8580 kg/m

Mass per Unit Area 1 oz/ft2 0.305152 kg/m2

1 lb/ft2 4.88243 kg/m2

1 lb/in2 703.070 kg/m2

1 UK ton/mile2 3.92290x10-4 kg/m2

Density 1lb/ft3 16.0185 kg/m3

1lb/UK gal 99.7763 kg/m3

1 lb/US gal 119.826 kg/m3

A P P E N D I X B

SI Conversion Factors

A P P E N D I X | 133

Quantity Unit Conversion FactorDensity 1slug/ft3 515.379 kg/m3

1ton/yd3 1328.94 kg/m3

1lb/in3 27.6799 Mg/m3

Specific 1in3/lb 36.1273 cm3/kgvolume 1ft3/lb 0.0624280 m3/kg

Velocity 1in./min 0.042333 cm/s1 ft/min 0.00508 m/s1ft/s 0.3048 m/s1mile/h 1.60934 km/h1UK knot 1.85318 km/h1International knot 1.852 km/h

Acceleration 1ft/s2 0.3048 m/s2

Mass flow rate 1lb/h 1.25998x10-4 kg/s1UK ton/h 0.282235 kg/s

Force (weight) 1dyne 10-3 N1pdl (poundal) 0.138255 N1ozf (ounce) 0.278014 N1lbf 4.44822 N1kgf 9.80665 N1tonf 9.96402 kN

Force (weight) 11bf/ft 14.5939 N/mper unit length 1lbf/in 175.127 N/m

1tonf/ft 32.6903 kN/m

Force (weight) 1pdl/ft2 1.48816 N/m2

per unit area (pressure) 1lbf/ft2 47.8803 N/m2

1mm Hg 133.322 N/m2

1in H20 249.089 N/m2

1ft H20 2989.07 N/m2

1in.Hg 3386.39 N/m2

1lbf/in2 6.89476 kN/m2

1bar =105 N/m2

1 std. atmosphere 101.325 kN/m2

1tonf/ft2 107.252 kN/m2

1 mm H20 =9.8067 N/m2(=1g)

Specific wt 1 lbf/ft3 157.088 N/m3

1 lbf/UK gal 978.471 N/m3

1 tonf/yd3 13.0324 kN/m3

1 lbf/in3 271.447 kN/m3

Moment, torque 1 ozf in (ounce-force inch) 0.00706155 Nmor couple 1 pdl ft 0.0421401 Nm

1 lbf in 0.112985 Nm1 lbf ft 1.35582 Nm1 ton ft 3037.03 Nm

A P P E N D I X B


134 | A P P E N D I X

Quantity Unit Conversion FactorEnergy 1erg 10-7 Jor heat 1horsepower hour 2.68452 MJor work 1 therm = 10 cal 4.1855 MJ

1therm = 1 00 000 Btu 105.506 MJ1cal 4.1868 J1 Btu 1.05506 kJ1kWh 3.6 MJ

Power 1hp= 550 ft lbf/s 0.745700 kW1 metric horsepower (ch, PS) 735.499 W

Specific heat 1 Btu/lb deg F1 cal/g deg C 4.1868 kJ/kg K

Heat flow rate 1Btu/h 0.293071 W1kcal/h 1.163 W1 cal/s 4.1868 W

Intensity of heat flow rate 1 Btu/ft2h 3.15459 W/m2

Electric stress 1 kV/in. 0.039370 kV/mm

Dynamic viscosity 1 1b/ft s 1.48816 kg/m s

Kinematic viscosity 1 ft2/s 929.03 stokes

Calorific value or specific enthalpy 1 Btu/ft3 37.2589 kJ/m3

1 Btu/lb 2.326 kJ/kg1 cal/g 4.1868 J/g1 kcal/m3 4.1868 kJ/m3

Specific entropy 1 Btu/lb°R 4.1868 kJ/kg K

Thermal Conductivity 1 cal cm/cm2 s deg C 41.868 W/m K1Btu ft/ft2 h deg F 1.73073 W/m K

Gas constant 1ft lbf/lb °R 0.00538032 kJ/kg K

Plane angle 1rad (radian) 57.2958°1degree 0.0174533 rad = 1.1111 grade1minute 2.90888x10-4 rad = 0.0185 grade1second 4.84814x10-6 rad = 0.0003 grade

Velocity of rotation 1rev/min 0. 1 04720 rad/sBased on Ramsay and Taylor: SI Metrication: Easy to Use Conversion Tables (Chambers).

1 N/mm2 = 1 MPa1 psi = 6.9 kPa1kg = 2.2 lb1” = 25.4 mm1 UK gallon = 4.55 litre1kg = 9.81 N

1 UK gallon = 1.2 US gallon1m3 = 1000 litre(=1kl)1 Joule = 1 Nm1 kN/m = 1 N/mm1 atmosphere = 101.325 kPa =10.33m head

of water = 1 bar = 760 cm Hg

Common Approximate Conversions

A P P E N D I X B


A P P E N D I X | 135

SteelModulus of elasticity 207000 MPaLinear Coefficient of thermal expansion 12x10-6 mm/mm °CThermal conductivity 47 W/(m °C)Density 7850 kg/m3

Melting range 1510 – 1524 °CPoisson ratio 0.27

SINTAKOTEDensity 940 kg/m3

Cement LiningModulus of elasticity 21000 MPaDensity 2400 kg/m3

SoilDensity (see Table 13.1)Bearing pressures (see Table 12.2)Moduli of soil reaction - E'e and E’n (see Table 13.3)

Water- - - - Kinematic Surface Vapour Bulk modulus

- Specifiic - Viscosity Viscosity Tension Pressure of elasticity

Temp Weight Density kg/ms m2/s N/m Head -

°C N/m3 kg/m3 x 10-3 x 10-6 x 102 m MPa0 9805 999.9 1.792 1.792 7.62 0.06 20405 9806 1000.0 1.519 1.519 7.54 0.09 206010 9803 999.7 1.308 1.308 7.48 0.12 211015 9798 999.1 1.140 1.141 7.41 0.17 214020 9789 998.2 1.005 1.007 7.36 0.25 220025 9779 997.1 0.894 0.897 7.26 0.33 222030 9767 995.7 0.801 0.804 7.18 0.44 223035 9752 994.1 0.723 0.727 7.10 0.58 224040 9737 992.2 0.656 0.661 7.01 0.76 227045 9720 990.2 0.599 0.605 6.92 0.98 229050 9697 988.1 0.549 0.556 6.82 1.26 230055 9679 985.7 0.506 0.513 6.74 1.61 231060 9658 983.2 0.469 0.477 6.68 2.03 228065 9635 980.6 0.436 0.444 6.58 2.56 226070 9600 977.8 0.406 0.415 6.50 3.20 225075 9589 974.9 0.380 0.390 6.40 3.96 223080 9557 971.8 0.357 0.367 6.30 4.86 221085 9529 968.6 0.336 0.347 6.20 5.93 217090 9499 965.3 0.317 0.328 6.12 7.18 216095 9469 961.9 0.299 0.311 6.02 8.62 2110100 9438 958.4 0.284 0.296 5.94 10.33 2070

Saline waters TSS(mg/l)

fresh water < 500marginal 500 to 1000brackish 1000 to 3000Saline waters > 3000sea water 35000TSS = Total soluble salts mg/l

A P P E N D I X C

Material Properties

136 | A P P E N D I X

1. Luscher, U

"Buckling of Soil surrounded tubes"

Jour. Soil Mech & Foundations Division

ASCE 92:6:213, 215 (Nov 1966)

2. Molin, Jan

"Principles of calculation for underground plastic pipes – calculation of loads, deflection, strain"

International Organization for Standardization

ISO Bulletin 2:10:21 (Oct 1971)

3. Spangler MG, Handy RL

"Soil Engineering", 4th edition

Harper & Row, New York, 1982

4. Clarke NWB

"Buried Pipelines - A manual of structural design and installation"

MacLaren and Sons, London,1968

5. Compston DG, Cray P, Schofield AN, Shann CD

"Design and construction of buried thin-wall pipes"

Construction Industry Research and Information Association

CIRIA UK Report 78, July 1978

6. Marston, Anson

"The theory of external loads on closed conduits in the light of the latest experiments"

Proc. Ninth Annual Meeting Highway Res. Board. Dec 1929

7. Melbourne and Metropolitan Board of Works

"Hydrogen Sulphide Control Manual"

Technological Standing Committee on Hydrogen Sulphide

Corrosion in Sewerage Works. Dec 1989

8. Skeat, WO (Ed)

Institution of Water Engineers

"Manual of British Water Engineering Practice", Third Edition

Heffer & Sons, Cambridge, 1961

9. Miller DS

"Internal flow systems". Second ed.

BHRA, 1990

10. Boussinesq, J

"Application des Potentiels a l Etude de l Equilibre et du Mouvement des Solids Elastiques”

Gauthier-Villars, Paris, 1885

11. AWWA

Manual of water supply practices

M11 "Steel pipes – a guide for design and installation"

12. Schorer, H

"Design of large pipelines"

Trans. ASCE, 88:1011 (1933)

13. Ligon, JB and Mayer, GR

"Coefficient of friction for pipe coating materials"

Pipe Line Industry

42 (2) PP 51-54, Feb 1975

14. Parmakian, J

"Water Hammer Analysis"

Dover, New York, 1963

15. Streeter, VL and Wylie, EB

"Fluid Transients"

McGraw-Hill, New York, 1978

16. Pickford, J

"Analysis of Water Surge"

Gordon and Breach, New York, 1969

17. Watters, GZ

"Modern Analysis and Control of Unsteady Flow in Pipelines"

Anne Arbor, Michigan, 1980

18. Webb, TH

"Water Hammer Control in Pipelines 1981"

James Hardie, Sydney, 1981

A P P E N D I X D

References

A P P E N D I X | 137

AS 1281 Cement Mortar Lining of Steel Pipes and Fittings

AS 1289 – E1.2 Method of Testing Soil for Engineering Purposes – determination of dry density / moisture content relation of soil using standard compaction.

AS 1289 – E3 Method of Testing Soil for Engineering Purposes – determination of the field dry density of a soil

AS 1289.5.4.1 Method of Testing Soil for Engineering Purposes – dry density moisture variation and moisture ratio

AS 1289.5.6.1 Method of Testing Soil for Engineering Purposes – density index method for a cohesionless material

AS 1579 Arc Welded Steel Pipes and Fittings for Water and Waste-Water

AS/NZ S1594 Hot Rolled Steel Flat Products

AS 1646 Elastomeric Seals for Waterworks Purposes

AS 2129 Flanges for Pipes, Valves and Fittings

AS 2200 Design Charts for Water Supply and Sewerage

AS/NZ S2566.1 Buried Flexible Pipelines – Structural Design

AS 2885 Pipelines – Gas and Liquid Petroleum

AS 3678 Structural Steel – Hot-rolled Plates, Floor-plates and Slabs

AS 4087 Metallic Flanges for Water-works Purposes

AS 4321 Fusion – bonded Medium – density Polyethylene Coatings and Linings for Pipes and Fittings

AS 4799 Installation of Underground Utility Services and Pipelines Within Railway Boundaries

AS/NZ 9001 Model for Quality Assurance

ASTM C177 Standard Test Method for Steady State Heat Flux Measurements and Thermal Transmission Properties by means of the Guarded-Hot-Plate Apparatus

ASTM D2240 Standard Test Method for Rubber Property – durometer hardness

ASTM D2487.9 Classification of Soils for Engineering Purposes

ASTM D4060 Standard Test Method for Abrasion Resistance of Organic Coatings by the Tauber Abraser

ASTM G8 Standard Test Methods for Cathodic Disbondment of Pipeline Coatings

ASTM G13 Standard Test Method for Impact Resistance of Pipeline Coatings (Limestone drop test)

ASTM G14 Standard Test Method for Impact Resistance of Pipeline Coatings (Falling weight test)

IEC 60093 Methods of Test for Volume Resistivity and Surface Resistivity of Solid Electrical Insulating Materials

IEC 60243 Electrical Strength of Insulating Materials – test methods – tests at power frequencies

A P P E N D I X E

Standards Referenced in Text

DivisionalOfficeTyco Water Pty LtdABN 75 087 415 745ACN 087 415 745

Dursley RoadYennora 2161PO Box 141 FairfieldNew South Wales 1860Telephone 61 2 9721 6600Facsimile 61 2 9721 [email protected]

www.tycowater.com

RegionalMarketing OfficesBrisbane

39 Silica StreetCarole Park 4300PO Box 162 Carole ParkQueensland 4300Telephone 07 3712 3625Facsimile 07 3271 [email protected]

Dursley RoadYennora 2161PO Box 141 FairfieldNew South Wales 1860Telephone 02 9721 6600Facsimile 02 9721 [email protected]

60A Maffra StreetCoolaroo 3048PO Box 42 DallasVictoria 3047Telephone 03 9301 9115Facsimile 03 9309 [email protected]

45 Guthrie StreetOsborne Park 6017PO Box 1495 Osborne Park BCWestern Australia 6916Telephone 08 9346 8555Facsimile 08 9346 [email protected]

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