Pipeline Valve Spacing - Comparison of Codes

7/21/2019 Pipeline Valve Spacing - Comparison of Codes

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TABLE D1. PIPELINE VALVE SPACING AND DESIGN REQUIREMENTS IN GAS TRANSMISSION PIPELINE CODES

No. Pipeline Code Code Approach Valve Spacing

Basis

Valve spacing Reqts...... Val

1 US B31.8-1995 Edition Design is based on a class

location concept with valve

spacing, and allowable

stress levels based on theclass location.

Building Density/

class location.Class 1. Para. 846.11, "the

spacing between valves on

a new transmission line

shall not exceed 20 mi.inLocation Class 1."

Class 2.Para.846.11, "the



shall not exceed 15 mi.inLocation Class 2.




shall not exceed 10 mi.inLocation Class 3 ."




shall not exceed 5 mi.inLocation Class 4"

846.2

not re

autom

the Cof au

prese

provid

piping

Their

shall

the o

UNIF

LOCA

HISTORICAL DATA 1955-1968

CODES

Class 1, 20 mile spacing Class 2, 15 mile spacing Class 3, 8 mile spacing Class 4, 5 mile spacing

2 US 49CFR Part 192 Based on ASME B31.8.

Design rules are based on

a class location concept.

The class location concept

was modified from that in

the B31.8 Code in 1968 to

a specific number ofhouses in a 1/4 mile width,

one mile long with only

one density index .

Building Density 192.179(4) Each point on a

pipeline in a Class 1

location must be within 10

miles of a sectionalizing

block valve.

192.179 (3) Each point on

a pipeline in a Class 2

location must be within 7.5


block valve.



location must be within 4


block valve.



location must be within 2.5


block valve.

192.1

and t

open

must

and p

tamp

UNIF

LOCA

HISTORICAL DATA-1968

D1


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Basis


3 Canadian Z662-94, Oil and

Gas Pipeline Systems Note,

a revision is due out in 1997 but

the areas of interest hereinhave not changed.

Based on ASME B31.8 .

Specified design rules

based on a class location

concept.

4.4.3, Valves shall

be located

upstream and

downstream of anypipeline segment at

a spacing not

greater than the

applicable value

given in Table 4.6

Table 4.6 shown in

valve spacing

reqts... columns

Table 4.6 as follows: For

gas pipelines in Class 1

Location, valves are not

required.

Table 4.6 as follows: For

gas pipelines in Class 2

Location, 25 km (15.6

miles) valve spacing.

Table 4.6 as follows: Class

3 Location, 13 km (8.1

miles) valve spacing.

Table 4.6 as follows: Class

4 Location, 8 km (5miles)

valve spacing.

There

for va

on ga

lines requir

autom

autom

shall

UNIF

LOCA

4 Australian SAA AS 2885-1987 Based on a class location

concept where the classes

are based on individual

size and not number of

houses, similar in some

respects to IGE TD/1.

Class Location Table 3.4, Location Class

R1, as required

Table 3.4, Location Class

R2, 30 km. max. (18.8

mi.)

Table 3.4, Location Class

T1 and T2, 15 km. max.

(9.4 mi.)

Valve

that in

the va

exped

Wher

valve

opera

UNIF

LOCA

D2


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Basis

Valve spacing Reqts...... Valv

5 UK Pipelines Safety

Regulations 1996

A risk based approach that

requires that the lines be

designed, operated and

maintained so that the riskto the public is acceptable.

No specified

spacing

requirements.

Emergency shut-down valves are

required.

Sched. 3 requires

emergency shut-down

valves to be normally

closed valves, be capableof being closed, be able to

pass equipment for

inspecting and testing, be

protected from damage

arising from fire, explosion

or impact and be

maintained .

Sched

emerg

valve s

of beinperson

(b) aut

operat

emerg

system

installa

pipelin

6 Institute of Gas Engineers

TD/1 Edition 3, 93

Design basis based on

class location concept

defined on the basis of

number of persons / unit

area.

Judgment and

operational

considerations

6.13.1 In a cross-country

pipeline, valves should be

provided at periodic

intervals and may be hand-

operated, automatic or

remotely controlled.

6.13.1 In built-up areas,

the spacing of valves

should be reduced. In

determining the spacing of

valves, consideration

should also be given to

operating pressure,

pipeline diameter, time

taken to arrive at the valve

site, (cont.)

6.13.1

hand o

or rem

probability of leakage, theneed for valves for

operational purposes, the

position of the nearest

offtakes and other existing

valves. 6.13.2 The valves

should be installed in

readily accessible

positions.

UNIFO

LOCA

D3


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Basis


7 ISO 13623, Draft 9/7/96 Design is based on a class

location concept.

6.11 Place where

required for

operation,

maintenance, and

control of

emergencies

No specific requirements. 6.11

opera

isolat

estab

deter

UNIFLOCA

8 NEN 3650 (Netherlands) Code specifies two design

approaches; 1) a risk

approach that assures that

each transport pipeline is

designed, constructed and

operated such that the

additional risk to the

surrounding area is

acceptable, i.e., 2.5- 10 MPa

(363-1450 psi) and 2

(pressure >1.2 - 2.5 MPa

(174-363 psi). In addition,

there are 5 Categories, B,

I, II, III, IV (cont.)

No specific

requirements

presented

Not more than 30 km (18.6 mi) apart. They are to be on both sides of water obstacles crossed by pipelines that

are crossed by two or more lines.

No m

The gas design categories

are a function of : gas

versus oil, diameter and

pressure; buried, on

ground, or above ground;

road crossings, railroad

crossings, river crossings;

distances to valves,

compressor stations and

gas treatment plants,

(cont.)

and stability of the ground.

10 Euro Norm p EN 1594

(CEN/TC 234)

Design requirements are

specified for buried piping,

piping in a tunnel

continuously supported

and in stations. No class

locations are defined

No specific valve spacing requirements 6.5 P

sectio

which

autom

contr

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Basis

Valve spacing Reqts...... Valv

This is a code that has

minimum requirements for gas

pipelines. If it is more stringent

than a countries code it wouldapply (European countries.) It

is weighted on the maintenance

and operation of pipelines.

Applies to pipelines operated at

>16 bar.

11 German DIN 2470, 2413, and

Construction Code 463

Bases design on the

elongation properties of the

steel. No class locations

are included.

German Standard 463 , Par.. 3.2.2 , indicates that the distance between two main shut-off devices is determined

by the local conditions and requirements for supply; a distance of 10 to 18 km (6 to 11.3 mi) is generally

adequate.

N

12 Algerian Pipeline Code -

Safety Regulations

Concerning Transportation'

Pipelines of Combustible Gas

Based on Class Locations

which are defined on the

basis of population

Based on Class

Locations

Article 31, Spacing

between two gate valves in

Zones 1 and 1a will not

exceed 10 Km (6.1 mi.). Inurban areas, the volume of

gas measured under

normal conditions, between

two successive valves shall

not exceed 90,000 cu.

meters.

Article 31, Spacing

between two gate valves in

Zones 2 and 3 will not

exceed 20 km (12.2 mi.).In urban areas, the volume

of gas measured under

normal conditions, between

two successive valves shall

not exceed 90,000 cu.

meters.

Article

other

rapidly

flow, eautom

comm

install

on the

13 French Pipeline Design Code Based on Class Locations

which are defined on the

basis of population

Based on three

Class Locations

20 km in Class 1 20 km in Class 2 10 km in Class 3 None

Information is based on verbal

information obtained from Gas

de France.

All class locations have a requirement for the gas volume between valves to be 90,000 cu. meters or less. UNIFO

LOCA

14 Regulations Concerning

Transportation of Petroleum

in Onshore Pipelines, 1986-

Norway Directorate for Fireand Explosion Prevention

Based on the Canadian Z

183 and Z 184.

Class Location 32 km (20 mi) in Class 1 24 km (15 mi) in Class 2 12 km (7.5 mi) in Class 3 8 km (5 mi) in Class 4 None

UNIFO

LOCA

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No. Pipeline Code

1 US B31.8-1995 Edition

2 US 49CFR Part 192

Pipeline Corridor for

Class Location

Retroactive

Application?

Discussion Design Basis

220 yds (200 m) on either

side of the pipeline

Yes, with regard to the

design stress (Class

Location change). No,

with regard to valvespacing.

846.21c Spacing may be

adjusted slightly to permit a

valve to be installed in a

more accessible location,with continuous accessibility

being the primary

consideration.

Building Density (population

density) with the design

factors based on nominal

wall thickness and outsidediameter.

Class 1, Div. 1, 0.80 de

factor for new constructi

table 841.114A; Div. 2,

design factor, per Table

841.114A for new const

(Div. 2.) for all API 5L pip

except furnace butt weld

0.43 design factor for fu

(contd)

846.21d, Automatic valve

closures are not required.

butt weld pipe. 0.60 des

factor for (1) crossing of

unimproved public roads

highways, or public stree

hard surfaces, and railro

without casings and (2)

encroachment of pipelin

mains on roads, (cont.)

highways or public stree

hard surfaces and railro

Also at fabricated assem

and pipelines on bridges

0.72 design factor for all

road and railroad crossin

0.50 design factor for

compressor station pipin

near concentration of pe

One mile density index,

count the number of

buildings in a zone one-halfmile on each side of the

pipeline and one mile long.

The 10 mile density index is

the sum of the one mile

density indexes for any 10

mile length of line.

Class location is the basis

for design.

Class 1, 0.72 design fac

220 yds (200 m) on either

side of the pipeline

Yes, per Par... 192.609

and 192.611. with regard

to design factor. No with

regard to valve spacing.

Building Density with the

design factors based on

nominal wall thickness and

outside diameter.

Class 1, 0.72design fac

192.111.

0.60 design factor or les

steel pipe in Class 1 loca

that: (1) Crosses the rig

way of an unimproved p

road, with a casing; (con

(2) Crosses without a ca

makes a parallel encroa

on, the right-of-way of ei

hard surfaced road, a hig

a public street , or a railr

(cont.)

(3) Is supported by a veh

pedestrian, railroad, or pbridge; or

(4) Is used in a fabricate

assembly, or is used wit

pipe diameters in any dir

from the last fitting of (co

a fabricated assembly, o

than a transition piece o

elbow used in place of a

bend which is not assoc

with a fabricated assemb

0.50 design factor for ste

in a compressor station,

regulating station, or me

station; and steel pipe, a pipe riser, on a platfor

located offshore or in inla

navigable waters.

D6


7/10

No. Pipeline Code

3 Canadian Z662-94, Oil and

Gas Pipeline Systems Note,

a revision is due out in 1997 but

the areas of interest hereinhave not changed.

4 Australian SAA AS 2885-1987


Class Location

Retroactive

Application?


Class Location areas shall

extend 200 m (220 yds.) on

both sides of the centerline

of any continuous 1.6 km (1mi.) length of pipeline

except as defined at the

ends.

Yes, Par. 10.7.1.

indicates that where class

locations change as a

result of changes inpopulation density or

location development, an

engineering assessment

shall be made to

determine if the pipeline

is satisfactory for the

changed class location.

4.4.4 It shall be permissible

to adjust the valve spacing

and location specified in

Clause 4.4.3 based onfactors such as operational,

maintenance, access, and

system design

considerations. Note: Valve

spacing adjustments should

not (cont.)

Population Density using a

Class Location factor, a

proximity factor and a

design factor of 0.8. Wallthickness is the design wall

thickness and the diameter

is the outside diameter of

the pipe. (cont.)

Class 1, Table 4.1, Gen

and cased crossings hav

allowable stress of 0.8

(1.00*0.8) SMYS. and Other* have an allow

stress of 0.6 (0.75*0.8)

Railways and stations ha

allowable stress of 0.5

(0.625*0.8) SMYS.

exceed 25 % of the

applicable distances listed in

Table 4.6.

Nominal wall thickness

equals the design thickness

plus the corrosion

allowance, plus the

threading and groove

allowances. Nominal wallcannot be less than the

design wall thickness.

Outside diameter of the pipe

and the SMYS are used

*Other: Piping that is (a)

assembly; or with five

4.4.9 For gas pipeline

systems, blowdown valves

shall be located so that the

sections of transmission

lines between sectionalizing

valves can be blown down.

Sizes and capacities of the

connections for blowing

down transmission lines

shall be (cont.)

in pla

such that, under emergency

conditions, the section can

be blown down as rapidly as

practicable. Locations of

blowdown valves shall be

such that the gas can be

blown to the atmosphere

without undue hazard.

There is no specificdefinition of Corridor width

for determining Location

Types. Par. 3.5.2.9 states"

Where a point on a pipeline

in a Class R1 location or a

Class R2 location is within

100 m of a location where

the average daily

congregation is (cont.)

3.5.2.8Yes at intervalsnot exceeding 5 years,

and where necessary,

appropriate corrective

action shall be taken.

Concentration of thepopulation without specific

building density

requirements. Outside

diameter is used with the

nominal wall thickness which

cannot be less than 10 mm

(0.393 inch) where wall

thickness and depth of

cover provide third party

protection.

3.6 & 3.7 Class R1. Desfactor is 0.72 with a third

damage factor of 1 resu

design factor of 0.72. (A

the SMYS of a published

specification unless the a

yield strength is determin

field test.) Min. w.t.=10 m

(3.7.2.2)

more than 20 people, the

pipeline shall be considered

to be in a Class t1 locationfor a distance of 100 m in

both directions from that

point. It appears that 100 m

is the corridor width.

3.1.5.2 Required wall

thickness cannot be less

than pressure designthickness (PD/2sigma y)

plus manufacturing under

tolerance if greater than

12.5%, plus corrosion,

threading and machining

tolerance.

D7


8/10

No. Pipeline Code

5 UK Pipelines Safety

Regulations 1996

6 Institute of Gas Engineers

TD/1 Edition 3, 93


Class Location

Retroactive

Application?


Not applicable Yes, requires that

modification,

maintenance or other

work on a pipeline iscarried out in such a way

that its soundness and

fitness for the purpose for

which it has been

designed will not be

prejudiced.

Reg. 5, that a pipeline shall

be designed to withstand

the expected strains and

processes. Reg. 8, that apipeline be constructed of

suitable materials. Reg. 9,

that it be constructed and

installed that it is sound and

fit for its purpose.

No specific requirements

than that it suitable for th

intended usage.

Reg. 11, that the safe

operating limits of a pipeline

be established and not

exceeded, save for testing.

Reg. 12 that adequate

arrangements be made for

dealing with incidents andemergencies involving a

pipeline.

6.8.2 Population density,

expressed as the number of

persons per unit hectare,

should be the average for

each 1.6 km (1 mi.) of

pipeline in a strip centered

on the pipeline of a width 8

times the minimum building

proximity distance (BPD) for

a (cont.)

1) Min. wall; 2) Outside

diameter of pipe, 3)

Population density; 4)

Fatigue cycles and 5)

specified minimum yield

stress.

6.8.4.1 Design factor s

not exceed 0.72and de

pressure should not exc

bar (1500 psi). (cont.)

Type R area pipeline as

defined in Figure 2. (Figure

2 presents BPD that range

from 10 to 110 m. For 508

mm (20 inch) diameter lines

at 66.7 bar (1000 psi), the

BPD ranges from 50 to 90

m.

6.8.4.2 If wall thickness

exceeds 19.1 mm (0.75

then 19.1 mm will suffice

provided the design fact

less than 0.5. Also, if ris

analysis justifies it, the B

from Table 3 S Type are

be used (Appendix 3 pro

guidelines.)

6.8.4.2 When design fac

less than 0.3, BPD in Ta

may be used, other wise

values.

TRAFFIC: 6.11.1 Pipeli

which either cross, or en

with, the appropriate pro

distance of a high densit

route, should have a nom

thickness of not less tha

mm (0.469-in). The des

factor should not exceed

(cont.)

However, when this calls

pipe with a nom. wall thi

of 19.1 mm (0.75 in) , th

mm pipe is acceptable,

that it does not result in t

design factor exceeding

higher design factor may

justified by risk analysis.

6.11.2 Pipelines crossin

running within the bound

other traffic routes shoul

a nom. wall thickness of

than 9.52 mm (0.375-in)

should have impact prot

The design factor should

exceed 0.30. (cont.)

D8


9/10

No. Pipeline Code

7 ISO 13623, Draft 9/7/96

8 NEN 3650 (Netherlands)

9 SNIP 2.05.06-85 Russian

Pipeline Code

10 Euro Norm p EN 1594

(CEN/TC 234)


Class Location

Retroactive

Application?


However, when this calls

pipe with a nom. wall thi

of 19.1 mm (0.75 in) , th

mm pipe is acceptable, that it does not result in

design factor exceeding

higher design factor may

justified by risk analysis.

Annex B. Class 5,

multistory buildings, traffic

is heavy or dense, and

numerous underground

utilities.

400 m (440 yds) in width

centered on the pipeline and

for a sliding length of 1.5 km

(0.94 mi).

Outside diameter minus t

min., t min, and P int. - P

ext., Sigma y is SMYS at

max. design temp.

Class 1. 0.83

Same as US, Can. Class4.

A1.2 The corridor width is

based on a "critical

distance" on either side of

the pipeline. The length is

also taken as the "critical

distance". The critical

distance is a function of the

diameter and operating

pressure. (cont.)

Design factor based on

location class and whether it

is in a pipeline corridor. The

design factors are; 1.39

(0.72), 1.50 (.67), and 1.82

(.55) applied to the hoop

stress based on average

diameter (D-t) and tmin.

The allowable stress is the

SMYS.

Location class 1. In des

pipeline corridors,DF

(0.72) for mechanical da

protection. Other pipelin

= 1.39 (0.72).

For dia... of 8 in (200 mm),the critical distance is 4, 5,

and 5 m for 20-50, 50-80.

and 80-110 bar pressures

respectively. For 30 in (750

mm) dia..., the critical

distance is 30 and 35 m for

50-80 and 80-110 bar

pressures respectively.

(Table A2-1)

There is also a minimexample, 219.1 mm (8 i

and for 914 mm (3

crossings, canal cross

Allowable stresses

outside of a pipeline

corridor.

Location class 1. Outsid

designated pipeline co

Max. Allowable stress =0

SMYS or ).72 x 0.75 SM

which ever is lower.

Category IV, below Grd.

lines < 1200 mm (47.2 in)

in dia..,

None defined since class

location does not include a

width on the sides of the

pipeline.

Unknown The specified minimum

ultimate stress is the basis.

This is modified by the type

of pipe and the location

category of the pipe as well

as the load factor (how well

the load is known, i.e.,

seismic/soil movementloads versus pressure

loads).

Category B, m=0.60, s

allowable stress as 0.43

(for welded steel pipe wi

0.85 Y/U, this equals 0.5

SMYS. However, they h

load factor that ranges f

to 1.15. Thus, the allow

could be between 0.50 aSMYS.)

Maximum stress is 0.72

SMYS based on OD and

min wall thickness for buried

piping and piping

continuously supported in a

tunnel. In a station, the

maximum stress is 0.67

SMYS.

D9


10/10

No. Pipeline Code

This is a code that has

minimum requirements for gas

pipelines. If it is more stringent

than a countries code it wouldapply (European countries.) It

is weighted on the maintenance

and operation of pipelines.

Applies to pipelines operated at

>16 bar.

11 German DIN 2470, 2413, and

Construction Code 463

12 Algerian Pipeline Code -

Safety Regulations

Concerning Transportation'

Pipelines of Combustible Gas

13 French Pipeline Design Code

Information is based on verbal

information obtained from Gas

de France.

14 Regulations Concerning

Transportation of Petroleum

in Onshore Pipelines, 1986-

Norway Directorate for Fire

and Explosion Prevention


Class Location

Retroactive

Application?


Not applicable No DIN 2470 defines allowable

stress levels based on steel

yield strength.

200 m along the line, +/-

100 m perpendicular to the

line.

Code does not appear to

be retroactively applied

when zones change.

Thickness is based on the

min. wall, OD. The

allowable stress is limited to

a percent of the yield stressand or the ultimate stress.

Zone 3, 80 % minimum

stress (SMYS), or 60 %

ultimate stress (SMUS-s

minimum ultimate stressBased on t, which is nom

minus the under thickne

tolerance and the outsid

diameter.

A second requirement is

maximum operating pre

cannot exceed .85 times

test pressure which mus

least 90 % of the SMYP

A brief review indicated

reducing the stress by

200 m along the line, 100 m

perpendicular to the line.

Code does not appear to

be retroactively applied

when zones change.

Class Location, however,

information on use of min.

wall and average dia. was

not available.

Class 1, 0.73 SMYS

A route unit is determined

continuously along a

pipeline and is an area 1000

m along the line, 200 m oneither side of the line.

Class 1 and 2 locations

are to be survey annually.

Class 3 and 4 locations

are to be surveyed every6 months.

Class location Class 1, 0.72

Desi

D10

Pipeline Valve Spacing - Comparison of Codes

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