Manual de Tuberia de Polietileno

Design and Engineering Guidefor Polyethylene Piping

PolyPipe®

TABLE OF CONTENTS

CONTENTS

SECTION

Pipe Data and Pressure Ratings A Fluid Flow B Earthloading C Temperature Effects D Chemical Resistance E Installation F Marine Application G Slurry Application H Overhead Pipeline Application J Natural Gas Flow L Handling and Storage M Conversion Factors N Material Safety Data Sheet (MSDS) P

SUBJECT MATTER

SECTION

PAGE

Anchor Weight Design G 3 Bending Radius F 2 Cell Classification A 2 Coiled Pipe L 2 Critical Buckling Factors (Non-Supported) A 13 Design/Construction of Ballast Weights G 4 - 6 External Pressure Ratings A 16 - 17 Gravity Flow B 5 Hydrostatic Pressure Testing F 6 - 8 Internal Pressure Ratings A 15 - 16 Maximum Pulling Force, MPF F 3 Maximum Pulling Length, MPL F 3 Physical Properties A 1 Pipe Supports/Spacing J 1 - 2 Pipe Weights & Dimensions – PE3408 A 3 - 11 Pipe Weights & Dimensions – PE2406 L 4 - 5 Pressure Loss/Gain –Elevation B 3 Pressure Loss/Gain –Fittings B 4 Pressure Loss/Gain –Frictional B 2 Pressure Surge/Water Hammer B 7 Pressure Testing F 6 Sag J 1 Thermal Conductivity D 1 Thermal Expansion/Contraction D 1 - 3 Thrust Blocking F 2 Trench Configuration/Terminology F 5 UV Resistance M 3 Vacuum Systems A 18 Velocities – Liquid B 1 Velocities – Slurry H 3

iPolyPipe 12/05

TABLE OF CONTENTS (cont.)

TABLES

SECTION

PAGE

A-1 Nominal Physical Properties A 1 A-2 Pipe Weights and Dimensions, PE3408 (IPS) A 3 - 8 A-3 Pipe Weights and Dimensions, PE3408 (Metric) A 8 A-4 Pipe Weights and Dimensions, PE3408 (DIPS) A 9 - 11 A-5 Environmental Service Factors A 13 A-6 Internal Pressure Ratings for PolyPipe® A 15 - 16 A-7 External Pressure Ratings for PolyPipe®, Non-Supported Application A 16 - 17 A-8 Time Correction Factors A 18 B-1 Recommended Liquid Velocities B 1 B-2 Hazen-Williams Coefficients for Various Pipes B 3 B-3 Pressure Drop in Fittings B 4 B-4 Fullness Factors, Gravity Flow B 5 C-1 Design Limits for Ring Deflection C 1 C-2 Area Reduction Due to Ring Deflection C 2 C-3 Classification of Backfill Material C 3 C-4 Typical Soil Modulus Values C 4 D-1 Thermal Conductivity of Materials D 1 F-1 Minimum Bending Radius F 2 F-2 Tensile Yield Strengths F 3 F-3 Hydrostatic Test Phase Make-Up Amount F 8 G-1 Anchor Constant Values G 3 G-2 Suggested Concrete Weight Dimensions G 5 H-1 Suggested Fluid Velocities, Slurry H 3 L-1 Typical Maximum Flow Rates for Natural Gas Distribution Systems L 1 L-2 Pipe Weights and Dimensions, PE2406 (IPS) L 4 L-3 Pipe Weights and Dimensions, PE2406 (CTS) L 5 M-1 Loose Pipe Storage, Suggested Stacking Heights M 3

FIGURES

SECTION

PAGE

A-1 Operational Life Factors A 14 A-2 Temperature Corrections Factors A 14 C-2 Trench Coefficient Values C 3 C-3 Wall Buckling Diagram C 5 C-4 Resultant Surface Load Diagram C 6 C-5 H20 Highway Loading C 6 C-6 Cooper E-80 Loading C 7 F-1 Ditch Configurations F 1 F-2 Proper Backfill F 4 F-3 Trench Configuration F 5 F-4 Proper Haunching F 5 G-1 Schematics of Concrete Ballast Designs G 5 G-2 Typical Detail of Concrete Ballast G 6 J-1 Support Spacing for Intermittently Supported Pipelines J 1 M-1 Forklift Load Capacity M 2

iiPolyPipe 12/05

INTRODUCTION

PolyPipe® PE3408 high density, high molecular weight, polyethylene pipe and fittings are made from a polyethylene resin expressly developed for demanding pressure piping applications. The use of PolyPipe® PE3408 pipe and fittings, as prescribed in this Guide, can help assure a sound, functional, economical system. PolyPipe® polyethylene piping systems allow the design engineer the opportunity to select premium polyethylene piping materials to perform as well as or better than alternate materials due to any one of the inherent characteristics of polyethylene. These are as follows:

Long-Term Strength

Flexibility

Corrosion Resistance

Chemical Resistance

Toughness

Weatherabilty

Installed Cost

Ease of Installation

Failure Mechanism

Low Friction Loss

Non-toxic

Low Thermal Conductivity

No Galvanic Action

Abrasion Resistance While this Guide details the benefits of industrial and mining piping materials, the same nominal values can be applied to oil patch pipe, gas distribution pipe, water pipe and municipal wastewater pipe.

iiiPolyPipe 12/05

FOREWORD

The Design and Engineering Guide for Polyethylene Piping, hereinafter referred to as "Guide," defines engineering requirements deemed necessary for the safe design and construction of PolyPipe® polyethylene piping systems. While safety is a basic consideration in this Guide, the user should be aware of other safety measures to consider in the safe installation or operation of the piping system. This Guide contains prohibitions in some areas where practice can be unintentionally easily extended into an unsafe condition, and in other areas, "flags" of caution are offered. The Guide is intended to provide basic principles in areas of concern when designing a piping system. However, it does not replace the need for competent engineering evaluation and judgment. The Guide contains basic reference data and formulas necessary for design of a PolyPipe® piping system. These formulas are recognized industry standard adaptations and, in most cases, modified for ease of application to PolyPipe® systems. It is intended to state these in terms of basic design principles to the maximum extent possible, supplemented where necessary, with examples to obtain uniform and accurate interpretation. PolyPipe® also has available a CD Rom to aide in calculations of formulas presented in the Sections of this Guide. To request a CD Rom, please visit our website at www.polypipeinc.com. If additional technical assistance is needed, please contact the PolyPipe® Technical Services Department at (800) 433-5632.

A comprehensive, industry consensus design guide for the proper use of polyethylene pipe is available from the Plastics Pipe Institute (PPI). The design guide is available, free of charge, via download from the PPI website at www.plasticpipe.org.

ivPolyPipe 12/05

http://www.polypipeinc.com/

PIPE DATA

Table A-1 NOMINAL PHYSICAL PROPERTIES

POLYPIPE® PE3408 AND PE2406 PIPE MATERIAL

Nominal Value* PROPERTY ASTM TEST METHOD PE3408 PE2406

Cell Classification D3350 345464C 234363E Density, Natural D1505 0.946 gm/cc 0.940 gm/cc Density, Black (PE3408) or Yellow (PE2406) D1505 0.955 gm/cc 0.943 gm/cc Melt Index (190oC/2.16 kg) D1238 0.07 gm/10 min 0.2 gm/10 min Flow Rate (190oC/21.6 kg) D1238 8.5 gm/10 min 20 gm/10 min Flexural Modulus D790 136,000 psi 100,000 psi Elastic Modulus: short-term D638 125,000 psi 100,000 psi Elastic Modulus: long-term D638 30,000 psi 25,000 psi Tensile Strength @ Yield D638 3,500 psi 2,800 psi ESCR D1693 >10,000 hrs. failure >10,000 hrs. failure Slow Crack Growth, PENT F1473 >100 hrs. >1,000 hrs. HDB @ 73.4oF D2837 1,600 psi 1,250 psi HDB @ 140oF D2837 800 psi 1,000 psi UV Stabilizer (Carbon) D1603 2.5% 2.5% Brittleness Temperature D746 <-180oF <-180oF Melting Point D789 261oF 261oF Vicat Softening Temperature D1525 255oF 248oF Hardness D2240 64 64 Shore D Izod Impact Strength (Notched) D256 7 ft-lbf/in 10 ft-lbf/in Thermal Expansion Coefficient D696 1.0 x 10-4 in/in/oF 1.0 x 10-4 in/in/oF Poisson’s Ratio -- 0.42 0.42 Manning Roughness -- 0.01 0.01 Volume Resistivity D991 2.6 x 1016 Ω-cm 2.6 x 1016 Ω-cm Average Molecular Weight GPC 330,000 330,000 *Note: Nominal Values are not intended as specified limits.

A-1PolyPipe 12/05

CELL CLASSIFICATION ASTM material standards insure that resins produced for piping applications are capable of providing a consistent level of performance over the intended design life. The most prevalent ASTM material specification is ASTM D3350. Multiple physical properties are defined within this specification by the use of a cell-type format for the identification, close characterization and specification of material properties. The cell-type format consists of six (6) numbers and a letter. PolyPipe® high density, extra high molecular weight, PE3408 polyethylene pipe material has a cell classification of 345464C. The letter “C” denotes the color and UV stabilization and is in accordance with the following code: A – Natural, B – Colored, C – Black with 2% minimum carbon black, D – Natural with UV stabilizer, and E – Colored with UV stabilizer.

Property Method 0 1 2 3 4 5 6

Density, g/cm3 D1505 Unspecified 0.925 or lower

>0.925 – 0.940

> 0.940 – 0.955 >0.955 ----- -----

Melt Index D1238 Unspecified >1.0 1.0 – 0.4 <0.4 – 0.15 < 0.15 A

Flexural Modulus, psi D790 Unspecified <20,000 20,000 -

<40,000 40,000 – 80,000

80,000 – 110,000

110,000 - <160,000 >160,000

Tensile strength at Yield, psi D638 Unspecified <2200 2200 -

<2600 2600 - <3000

3000 - <3500

3500 - <4000 >4000

Slow Crack Growth Resistance

I. ESCR D1693 Unspecified

a. Test Condition A B C C ----- -----

b. Test Duration, h 48 24 192 600

c. Failure, max, % 50 50 20 20

II. PENT (hours) F1473 Unspecified

Molded plaque, 80oC, 2.4 MPa 0.1 1 3 10 30 100

Hydrostatic Design Basis, psi, (23oC) D2837 NPRB 800 1000 1250 1600

ARefer to 10.1.4.1 of ASTM D3350. BNPR = Not Pressure Rated. Being a polyethylene (PE) material, the abbreviation PE is used preceding the cell number P-E-3-4-5-4-6-4-C. The Plastics Pipe Institute (PPI), a division of the Society of the Plastics Industry, Inc., has rated PolyPipe® material as PE3408.

A-2PolyPipe 12/05

See ASTM D3035, F714 and AWWA C-901/906 for OD and wall thickness tolerances. Weights are calculated in accordance with PPI TR-7.

A-3

PolyPipe 12/05

Nominal SDR lb. per kg. perin. in. mm. in. mm. in. mm. foot meter

7 0.59 14.87 0.120 3.05 0.118 0.1757.3 0.60 15.14 0.115 2.92 0.114 0.170

1/2 0.840 21.34 9 0.64 16.31 0.093 2.37 0.095 0.1429.3 0.65 16.47 0.090 2.29 0.093 0.13811 0.68 17.22 0.076 1.94 0.080 0.119

11.5 0.69 17.40 0.073 1.86 0.077 0.114

7 0.73 18.59 0.150 3.81 0.184 0.2747.3 0.75 18.92 0.144 3.65 0.178 0.265

3/4 1.050 26.67 9 0.80 20.39 0.117 2.96 0.149 0.2229.3 0.81 20.59 0.113 2.87 0.145 0.21611 0.85 21.53 0.095 2.42 0.125 0.186

11.5 0.86 21.75 0.091 2.32 0.120 0.179

7 0.92 23.29 0.188 4.77 0.289 0.4307.3 0.93 23.70 0.180 4.58 0.279 0.415

1 1.315 33.40 9 1.01 25.53 0.146 3.71 0.234 0.3489.3 1.02 25.79 0.141 3.59 0.227 0.33811 1.06 26.96 0.120 3.04 0.196 0.291

11.5 1.07 27.24 0.114 2.90 0.188 0.280

7 1.16 29.39 0.237 6.02 0.461 0.6857.3 1.18 29.92 0.227 5.78 0.445 0.6629 1.27 32.23 0.184 4.68 0.372 0.554

1 1/4 1.660 42.16 9.3 1.28 32.55 0.178 4.53 0.362 0.53911 1.34 34.04 0.151 3.83 0.312 0.464

11.5 1.35 34.39 0.144 3.67 0.300 0.44613.5 1.40 35.54 0.123 3.12 0.259 0.386

7 1.32 33.64 0.271 6.89 0.603 0.8987.3 1.35 34.24 0.260 6.61 0.583 0.8679 1.45 36.89 0.211 5.36 0.488 0.726

1 1/2 1.900 48.26 9.3 1.47 37.26 0.204 5.19 0.474 0.70611 1.53 38.96 0.173 4.39 0.409 0.608

11.5 1.55 39.36 0.165 4.20 0.393 0.58513.5 1.60 40.68 0.141 3.57 0.340 0.50615.5 1.64 41.66 0.123 3.11 0.299 0.445

7 1.66 42.06 0.339 8.62 0.943 1.4037.3 1.69 42.81 0.325 8.26 0.911 1.3559 1.82 46.12 0.264 6.70 0.762 1.134

9.3 1.83 46.57 0.255 6.49 0.741 1.1032 2.375 60.33 11 1.92 48.70 0.216 5.48 0.639 0.951

11.5 1.94 49.20 0.207 5.25 0.614 0.91413.5 2.00 50.85 0.176 4.47 0.531 0.79015.5 2.05 52.07 0.153 3.89 0.467 0.69617 2.08 52.80 0.140 3.55 0.429 0.638

Weight

Table A-2PIPE WEIGHTS AND DIMENSIONS (IPS)

PE3408 (BLACK)

ActualOD Nominal ID Minimum Wall


A-4

PolyPipe 12/05


7 2.44 61.98 0.500 12.70 2.047 3.0477.3 2.48 63.08 0.479 12.18 1.978 2.9439 2.68 67.96 0.389 9.88 1.656 2.464

9.3 2.70 68.63 0.376 9.56 1.609 2.39511 2.83 71.77 0.318 8.08 1.387 2.065

3 3.500 88.90 11.5 2.85 72.51 0.304 7.73 1.333 1.98413.5 2.95 74.94 0.259 6.59 1.153 1.71615.5 3.02 76.74 0.226 5.74 1.015 1.51117 3.06 77.81 0.206 5.23 0.932 1.38621 3.15 79.93 0.167 4.23 0.764 1.13626 3.21 81.65 0.135 3.42 0.623 0.927

7 3.14 79.68 0.643 16.33 3.384 5.0377.3 3.19 81.11 0.616 15.66 3.269 4.8659 3.44 87.38 0.500 12.70 2.737 4.073

9.3 3.47 88.24 0.484 12.29 2.660 3.95811 3.63 92.27 0.409 10.39 2.294 3.413

4 4.500 114.30 11.5 3.67 93.23 0.391 9.94 2.204 3.28013.5 3.79 96.35 0.333 8.47 1.906 2.83615.5 3.88 98.67 0.290 7.37 1.678 2.49717 3.94 100.05 0.265 6.72 1.540 2.29221 4.05 102.76 0.214 5.44 1.262 1.87926 4.13 104.98 0.173 4.40 1.030 1.533

32.5 4.21 106.84 0.138 3.52 0.831 1.237

7 3.88 98.51 0.795 20.19 5.172 7.6977.3 3.95 100.27 0.762 19.36 4.996 7.4359 4.25 108.02 0.618 15.70 4.182 6.224

9.3 4.29 109.09 0.598 15.19 4.065 6.04911 4.49 114.07 0.506 12.85 3.505 5.216

5 5.563 141.30 11.5 4.54 115.25 0.484 12.29 3.368 5.01213.5 4.69 119.11 0.412 10.47 2.912 4.33415.5 4.80 121.97 0.359 9.12 2.564 3.81617 4.87 123.68 0.327 8.31 2.353 3.50221 5.00 127.04 0.265 6.73 1.929 2.87126 5.11 129.78 0.214 5.43 1.574 2.343

32.5 5.20 132.08 0.171 4.35 1.270 1.890

7 4.62 117.31 0.946 24.04 7.336 10.9177.3 4.70 119.41 0.908 23.05 7.086 10.5459 5.06 128.64 0.736 18.70 5.932 8.827

9.3 5.11 129.92 0.712 18.09 5.765 8.57911 5.35 135.84 0.602 15.30 4.971 7.398

6 6.625 168.28 11.5 5.40 137.25 0.576 14.63 4.777 7.10913.5 5.58 141.85 0.491 12.46 4.130 6.14715.5 5.72 145.26 0.427 10.86 3.637 5.41317 5.80 147.29 0.390 9.90 3.338 4.96721 5.96 151.29 0.315 8.01 2.736 4.07226 6.08 154.55 0.255 6.47 2.233 3.322

32.5 6.19 157.30 0.204 5.18 1.801 2.680

ActualOD Nominal ID Minimum Wall Weight

Table A-2 (cont'd)PIPE WEIGHTS AND DIMENSIONS (IPS)

PE3408 (BLACK)


A-5PolyPipe 12/05


7 6.01 152.73 1.232 31.30 12.433 18.5037.3 6.12 155.45 1.182 30.01 12.010 17.8729 6.59 167.47 0.958 24.34 10.054 14.962

9.3 6.66 169.14 0.927 23.56 9.771 14.54111 6.96 176.85 0.784 19.92 8.425 12.538

8 8.625 219.08 11.5 7.04 178.69 0.750 19.05 8.096 12.04913.5 7.27 184.67 0.639 16.23 7.001 10.41815.5 7.45 189.11 0.556 14.13 6.164 9.17417 7.55 191.76 0.507 12.89 5.657 8.41821 7.75 196.96 0.411 10.43 4.637 6.90126 7.92 201.21 0.332 8.43 3.784 5.631

7 7.49 190.35 1.536 39.01 19.314 28.7437.3 7.63 193.75 1.473 37.40 18.656 27.7649 8.22 208.73 1.194 30.34 15.618 23.242

9.3 8.30 210.81 1.156 29.36 15.179 22.58911 8.68 220.43 0.977 24.82 13.089 19.478

10 10.750 273.05 11.5 8.77 222.71 0.935 23.74 12.578 18.71713.5 9.06 230.17 0.796 20.23 10.875 16.18415.5 9.28 235.70 0.694 17.62 9.576 14.25117 9.41 239.00 0.632 16.06 8.788 13.07821 9.66 245.48 0.512 13.00 7.204 10.72126 9.87 250.79 0.413 10.50 5.878 8.748

32.5 10.05 255.24 0.331 8.40 4.742 7.058

7 8.89 225.77 1.821 46.26 27.170 40.4337.3 9.05 229.80 1.747 44.36 26.244 39.0569 9.75 247.57 1.417 35.98 21.970 32.695

9.3 9.84 250.03 1.371 34.82 21.353 31.77711 10.29 261.44 1.159 29.44 18.412 27.400

12 12.750 323.85 11.5 10.40 264.15 1.109 28.16 17.693 26.33013.5 10.75 272.99 0.944 23.99 15.298 22.76715.5 11.01 279.56 0.823 20.89 13.471 20.04717 11.16 283.46 0.750 19.05 12.362 18.39721 11.46 291.16 0.607 15.42 10.134 15.08126 11.71 297.44 0.490 12.46 8.269 12.305

32.5 11.92 302.73 0.392 9.96 6.671 9.928

7 9.76 247.90 2.000 50.80 32.758 48.7507.3 9.93 252.33 1.918 48.71 31.642 47.0899 10.70 271.84 1.556 39.51 26.489 39.420

9.3 10.81 274.54 1.505 38.24 25.745 38.31311 11.30 287.07 1.273 32.33 22.199 33.036

14 14.000 355.60 11.5 11.42 290.05 1.217 30.92 21.332 31.74613.5 11.80 299.76 1.037 26.34 18.445 27.44915.5 12.09 306.96 0.903 22.94 16.242 24.17017 12.25 311.25 0.824 20.92 14.905 22.18121 12.59 319.70 0.667 16.93 12.218 18.18326 12.86 326.60 0.538 13.68 9.970 14.836

32.5 13.09 332.40 0.431 10.94 8.044 11.970

Table A-2 (cont'd)

Weight

PIPE WEIGHTS AND DIMENSIONS (IPS)PE3408 (BLACK)



A-6

PolyPipe 12/05


7 11.15 283.32 2.286 58.06 42.786 63.6737.3 11.35 288.38 2.192 55.67 41.329 61.5049 12.23 310.67 1.778 45.16 34.598 51.487

9.3 12.35 313.76 1.720 43.70 33.626 50.04111 12.92 328.08 1.455 36.95 28.994 43.149

16 16.000 406.40 11.5 13.05 331.48 1.391 35.34 27.862 41.46413.5 13.49 342.58 1.185 30.10 24.092 35.85215.5 13.81 350.81 1.032 26.22 21.214 31.57017 14.00 355.72 0.941 23.91 19.467 28.97021 14.38 365.37 0.762 19.35 15.959 23.74926 14.70 373.26 0.615 15.63 13.022 19.378

7 12.55 318.73 2.571 65.31 54.151 80.5867.3 12.77 324.42 2.466 62.63 52.307 77.8419 13.76 349.50 2.000 50.80 43.788 65.164

9.3 13.90 352.98 1.935 49.16 42.558 63.33311 14.53 369.09 1.636 41.56 36.696 54.610

18 18.000 457.20 11.5 14.68 372.92 1.565 39.76 35.263 52.47813.5 15.17 385.40 1.333 33.87 30.491 45.37615.5 15.54 394.67 1.161 29.50 26.849 39.95517 15.76 400.18 1.059 26.89 24.638 36.66621 16.18 411.04 0.857 21.77 20.198 30.05826 16.53 419.92 0.692 17.58 16.480 24.526

32.5 16.83 427.38 0.554 14.07 13.296 19.787

7 13.94 354.15 2.857 72.57 66.853 99.4897.3 14.19 360.47 2.740 69.59 64.576 96.1009 15.29 388.34 2.222 56.44 54.059 80.449

9.3 15.44 392.20 2.151 54.62 52.541 78.18911 16.15 410.09 1.818 46.18 45.304 67.420

20 20.000 508.00 11.5 16.31 414.35 1.739 44.17 43.535 64.78713.5 16.86 428.23 1.481 37.63 37.643 56.01915.5 17.26 438.52 1.290 32.77 33.146 49.32717 17.51 444.65 1.176 29.88 30.418 45.26621 17.98 456.72 0.952 24.19 24.936 37.10826 18.37 466.58 0.769 19.54 20.346 30.279

32.5 18.70 474.86 0.615 15.63 16.415 24.429

9 16.82 427.17 2.444 62.09 65.412 97.3439.3 16.98 431.42 2.366 60.09 63.574 94.60911 17.76 451.10 2.000 50.80 54.818 81.578

11.5 17.94 455.79 1.913 48.59 52.677 78.39322 22.000 558.80 13.5 18.55 471.05 1.630 41.39 45.548 67.783

15.5 18.99 482.37 1.419 36.05 40.107 59.68617 19.26 489.11 1.294 32.87 36.805 54.77221 19.78 502.39 1.048 26.61 30.172 44.90126 20.21 513.24 0.846 21.49 24.619 36.637

32.5 20.56 522.35 0.677 17.19 19.863 29.559

Table A-2 (cont'd)




A-7PolyPipe 12/05


9 18.35 466.01 2.667 67.73 77.845 115.8479.3 18.53 470.64 2.581 65.55 75.658 112.59211 19.37 492.11 2.182 55.42 65.237 97.084

11.5 19.58 497.22 2.087 53.01 62.690 93.29424 24.000 609.60 13.5 20.23 513.87 1.778 45.16 54.206 80.668

15.5 20.72 526.22 1.548 39.33 47.731 71.03217 21.01 533.58 1.412 35.86 43.801 65.18421 21.58 548.06 1.143 29.03 35.907 53.43626 22.04 559.89 0.923 23.45 29.299 43.601

32.5 22.43 569.84 0.738 18.76 23.638 35.177

11 22.60 574.13 2.545 64.65 88.795 132.14211.5 22.84 580.09 2.435 61.84 85.329 126.98313.5 23.60 599.52 2.074 52.68 73.781 109.79815.5 24.17 613.93 1.806 45.88 64.967 96.682

28 28.000 711.20 17 24.51 622.51 1.647 41.84 59.618 88.72221 25.17 639.40 1.333 33.87 48.874 72.73226 25.72 653.21 1.077 27.35 39.879 59.346

32.5 26.17 664.81 0.862 21.88 32.174 47.880

11 24.22 615.14 2.727 69.27 101.934 151.69411.5 24.47 621.53 2.609 66.26 97.954 145.77113.5 25.29 642.34 2.222 56.44 84.697 126.04315.5 25.90 657.78 1.935 49.16 74.580 110.987

30 30.000 762.00 17 26.26 666.97 1.765 44.82 68.439 101.84921 26.97 685.07 1.429 36.29 56.105 83.49426 27.55 699.87 1.154 29.31 45.779 68.127

32.5 28.04 712.29 0.923 23.45 36.934 54.965

13.5 26.97 685.16 2.370 60.21 96.367 143.40915.5 27.62 701.63 2.065 52.44 84.855 126.278

32 32.000 812.80 17 28.01 711.44 1.882 47.81 77.869 115.88221 28.77 730.75 1.524 38.70 63.835 94.99726 29.39 746.53 1.231 31.26 52.086 77.513

32.5 29.91 759.78 0.985 25.01 42.023 62.538

15.5 31.08 789.33 2.323 58.99 107.395 159.82117 31.51 800.37 2.118 53.79 98.553 146.663

36 36.000 914.40 21 32.37 822.09 1.714 43.54 80.791 120.23126 33.06 839.84 1.385 35.17 65.922 98.102

32.5 33.65 854.75 1.108 28.14 53.186 79.149

15.5 36.26 920.89 2.710 68.83 146.176 217.53417 36.76 933.76 2.471 62.75 134.141 199.625

42 42.000 1066.80 21 37.76 959.10 2.000 50.80 109.966 163.64826 38.58 979.81 1.615 41.03 89.727 133.528

32.5 39.26 997.21 1.292 32.82 72.392 107.731

Table A-2 (cont'd)

Weight




Weights are calculated in accordance with PPI TR-7.

A-8PolyPipe 12/05


17 42.01 1067.16 2.824 71.72 175.205 260.73448 48.000 1219.20 21 43.15 1096.12 2.286 58.06 143.629 213.744

26 44.09 1119.79 1.846 46.89 117.194 174.40432.5 44.87 1139.67 1.477 37.51 94.552 140.709

21 48.55 1233.13 2.571 65.31 181.781 270.52054 54.000 1371.60 26 49.60 1259.76 2.077 52.75 148.324 220.730

32.5 50.48 1282.13 1.662 42.20 119.668 178.085

Table A-2 (cont'd)



MetricSize OD SDR lb. per kg. permm. in. in. mm. in. mm. foot meter

50 1.97 11 1.59 40.39 0.179 4.55 0.440 0.654

63 2.48 17 2.17 55.14 0.146 3.71 0.468 0.696

90 3.54 11 2.86 72.59 0.322 8.17 1.419 2.112

110 4.33 11 3.50 88.79 0.394 10.00 2.123 3.160 17 3.79 96.27 0.255 6.47 1.426 2.122

160 6.30 11 5.09 129.18 0.573 14.55 4.495 6.690 32.5 5.89 149.58 0.194 4.92 1.629 2.424

11 6.35 161.37 0.715 18.17 7.015 10.439200 7.87 17.6 6.92 175.82 0.447 11.36 4.560 6.786

32.5 7.36 186.86 0.242 6.15 2.542 3.783

11 7.94 201.77 0.895 22.72 10.966 16.320250 9.84 17.6 8.65 219.83 0.559 14.20 7.128 10.608

32.5 9.20 233.63 0.303 7.69 3.974 5.913

315 12.40 17.6 10.91 277.02 0.705 17.90 11.319 16.845 32.5 11.59 294.41 0.382 9.69 6.310 9.390

400 15.75 12 12.97 329.37 1.313 33.34 25.983 38.667

500 19.69 26 18.08 459.35 0.757 19.24 19.720 29.347

Table A-3

Weight

PIPE WEIGHTS AND DIMENSIONS (Metric)PE3408 (BLACK)

Nominal ID Minimum Wall


A-9PolyPipe 12/05


7 2.76 70.12 0.566 14.37 2.621 3.9009 3.03 76.89 0.440 11.18 2.119 3.15411 3.20 81.20 0.360 9.14 1.776 2.643

13.5 3.34 84.79 0.293 7.45 1.476 2.1963 3.960 100.58 15.5 3.42 86.83 0.255 6.49 1.299 1.934

17 3.47 88.04 0.233 5.92 1.192 1.77521 3.56 90.43 0.189 4.79 0.978 1.45526 3.64 92.38 0.152 3.87 0.798 1.187

32.5 3.70 94.02 0.122 3.09 0.644 0.958

7 3.35 85.00 0.686 17.42 3.851 5.7319 3.67 93.20 0.533 13.55 3.114 4.63411 3.87 98.42 0.436 11.08 2.609 3.883

13.5 4.05 102.77 0.356 9.03 2.168 3.2274 4.800 121.92 15.5 4.14 105.24 0.310 7.87 1.909 2.841

17 4.20 106.72 0.282 7.17 1.752 2.60721 4.32 109.61 0.229 5.81 1.436 2.13726 4.41 111.98 0.185 4.69 1.172 1.744

32.5 4.49 113.97 0.148 3.75 0.946 1.407

7 4.81 122.18 0.986 25.04 7.957 11.8429 5.27 133.98 0.767 19.47 6.434 9.57511 5.57 141.48 0.627 15.93 5.392 8.025

13.5 5.82 147.74 0.511 12.98 4.480 6.6686 6.900 175.26 15.5 5.96 151.29 0.445 11.31 3.945 5.871

17 6.04 153.40 0.406 10.31 3.620 5.38821 6.20 157.57 0.329 8.35 2.968 4.41726 6.34 160.97 0.265 6.74 2.422 3.604

32.5 6.45 163.83 0.212 5.39 1.954 2.908

7 6.31 160.25 1.293 32.84 13.689 20.3719 6.92 175.72 1.006 25.54 11.069 16.47211 7.31 185.57 0.823 20.90 9.276 13.805

13.5 7.63 193.77 0.670 17.03 7.708 11.4708 9.050 229.87 15.5 7.81 198.43 0.584 14.83 6.787 10.100

17 7.92 201.20 0.532 13.52 6.228 9.26921 8.14 206.66 0.431 10.95 5.106 7.59826 8.31 211.13 0.348 8.84 4.166 6.200

32.5 8.46 214.88 0.278 7.07 3.361 5.002

7 7.74 196.55 1.586 40.28 20.593 30.6459 8.49 215.53 1.233 31.33 16.652 24.78011 8.96 227.60 1.009 25.63 13.955 20.767

13.5 9.36 237.66 0.822 20.88 11.595 17.25510 11.100 281.94 15.5 9.58 243.38 0.716 18.19 10.210 15.194

17 9.72 246.78 0.653 16.58 9.369 13.94321 9.98 253.48 0.529 13.43 7.681 11.43026 10.19 258.95 0.427 10.84 6.267 9.327

32.5 10.38 263.55 0.342 8.68 5.056 7.525

Table A-4


PIPE WEIGHTS AND DIMENSIONS (DIPS)PE3408 (BLACK)

A-10PolyPipe 12/05



7 9.20 233.74 1.886 47.90 29.121 43.3379 10.09 256.30 1.467 37.25 23.548 35.04411 10.66 270.66 1.200 30.48 19.734 29.368

13.5 11.13 282.63 0.978 24.84 16.397 24.40212 13.200 335.28 15.5 11.39 289.42 0.852 21.63 14.439 21.487

17 11.55 293.47 0.776 19.72 13.250 19.71821 11.87 301.43 0.629 15.97 10.862 16.16426 12.12 307.94 0.508 12.90 8.863 13.189

32.5 12.34 313.41 0.406 10.32 7.151 10.641

7 10.67 270.92 2.186 55.52 39.124 58.2239 11.70 297.08 1.700 43.18 31.637 47.08111 12.35 313.72 1.391 35.33 26.513 39.456

13.5 12.90 327.59 1.133 28.79 22.030 32.78414 15.300 388.62 15.5 13.21 335.47 0.987 25.07 19.398 28.868

17 13.39 340.16 0.900 22.86 17.801 26.49121 13.76 349.39 0.729 18.51 14.593 21.71726 14.05 356.93 0.588 14.95 11.907 17.720

32.5 14.30 363.27 0.471 11.96 9.607 14.296

7 12.13 308.11 2.486 63.14 50.601 75.3039 13.30 337.85 1.933 49.11 40.917 60.89211 14.05 356.78 1.582 40.18 34.290 51.030

13.5 14.67 372.56 1.289 32.74 28.492 42.40116 17.400 441.96 15.5 15.02 381.51 1.123 28.51 25.089 37.336

17 15.23 386.84 1.024 26.00 23.023 34.26221 15.64 397.34 0.829 21.05 18.874 28.08726 15.98 405.92 0.669 17.00 15.400 22.918

32.5 16.26 413.13 0.535 13.60 12.425 18.490

7 13.59 345.29 2.786 70.76 63.553 94.5779 14.91 378.63 2.167 55.03 51.390 76.47711 15.74 399.84 1.773 45.03 43.067 64.091

13.5 16.44 417.52 1.444 36.69 35.785 53.25318 19.500 495.30 15.5 16.83 427.56 1.258 31.95 31.510 46.892

17 17.07 433.53 1.147 29.14 28.916 43.03121 17.53 445.30 0.929 23.59 23.704 35.27626 17.91 454.91 0.750 19.05 19.342 28.784

32.5 18.23 462.99 0.600 15.24 15.605 23.223

7 15.06 382.48 3.086 78.38 77.978 116.0449 16.51 419.40 2.400 60.96 63.055 93.83611 17.44 442.90 1.964 49.88 52.842 78.638

13.5 18.21 462.48 1.600 40.64 43.907 65.34120 21.600 548.64 15.5 18.65 473.60 1.394 35.40 38.662 57.536

17 18.91 480.22 1.271 32.27 35.479 52.79921 19.42 493.25 1.029 26.13 29.085 43.28326 19.84 503.90 0.831 21.10 23.732 35.317

32.5 20.19 512.85 0.665 16.88 19.147 28.494

Table A-4 (cont'd)




A-11PolyPipe 12/05


11 20.83 529.02 2.345 59.57 75.390 112.19313.5 21.75 552.41 1.911 48.54 62.642 93.22215.5 22.27 565.69 1.665 42.28 55.159 82.086

24 25.800 655.32 17 22.58 573.60 1.518 38.55 50.618 75.32821 23.20 589.16 1.229 31.21 41.495 61.75226 23.70 601.89 0.992 25.20 33.858 50.386

32.5 24.12 612.57 0.794 20.16 27.317 40.652

13.5 26.97 685.16 2.370 60.21 96.367 143.40915.5 27.62 701.63 2.065 52.44 84.855 126.278

30 32.000 812.80 17 28.01 711.44 1.882 47.81 77.869 115.88221 28.77 730.75 1.524 38.70 63.835 94.99726 29.39 746.53 1.231 31.26 52.086 77.513

32.5 29.91 759.78 0.985 25.01 42.023 62.538

Table A-4 (cont'd)



PRESSURE DESIGN A pipeline is defined as “a line of pipes for conveying water, gas, oil, etc.” These lines may operate at a positive pressure, negative pressure or atmospheric pressure in the performance of their design parameters. A piping system is acted upon by a multitude of design considerations: corrosion, ground entrained water, stray electro-magnetic currents, external loads by soil, water table, and wave and/or current action, thermal changes and the effects of ultraviolet light.

INTERNAL PRESSURE

PolyPipe® for industrial-municipal-mining applications is manufactured to specific dimensions as required in applicable American Society for Testing and Materials (ASTM) standards. Piping outside diameters may meet the IPS, DIPS or Metric systems. Wall thickness is based on the Dimension Ratio (DR) system, a specific ratio of the nominal outside diameter to the minimum specified wall thickness. Use of the DR number in the ISO equation, recognized as an equation depicting the relationship of pipe dimensions, both wall and OD, internal pressure carrying capabilities and tensile stress, in conjunction with a suitable design factor (DF) will give the design engineer confidence the pipe will not fail prematurely due to internal pressurization. To move a material along a pipeline, forces of gravity, or internal pressure, differentials are required. For atmospheric systems (gravity flow), gravitational forces provide the impetus for movement of heavier-than-air mass. To move the same against gravity (pressure flow) additive internal forces are generated, which must be recognized in the design stage in order to provide desired operational life. In some cases a gravity flow system must be treated comparable to the design consideration of a pressure flow system. Calculations for determining the internal pressure rating of PolyPipe® are based on the ISO equation2, which is:

(1)

Where P = Internal pressure, psi HDB = Hydrostatic Design Basis, (1600 psi for PE3408) DR = Pipe dimension ratio (D/t) D = Outside diameter, inches t = Minimum wall thickness, inches DF = Design factor (0.5 for water @ 73oF (23oC))

Use of additional factors will provide for a more defined performance characteristic for systems with higher operation temperatures, shorter operational time and system fluid other than water. These additional factors are defined as the following:

• F1 - Factor used where the operational life is less than 50 years. Refer to Figure A-1. • F2 - Temperature correction factor for service other than 73oF (23oC). Refer to Figure A-2. • F3 - Environmental factor utilized to compensate for the effect of substances other than water. Refer to

Table A-5. With the implementation of additional factors, the ISO equation2 now becomes:

(2)

2 ASTM D1598-97. Standard Test Method for Time-to-Failure of Plastic Under Constant Internal Pressure. Volume 8.04. American Society of Testing and Materials. Baltimore, 2004.

( ) DFDR

HDBP ⋅−

⋅=

12

( ) 32112 FFFDFDR

HDBP ⋅⋅⋅⋅−

⋅=

A-12PolyPipe 12/05

Where P = Internal pressure, psi HDB = Hydrostatic Design Basis, (1600 psi for PE3408) DR = Pipe dimension ratio (D/t) D = Outside diameter, inches t = Minimum wall thickness, inches DF = Design factor (0.5 for water @ 73oF (23oC)) F1 = Operational life factor (Figure A-1) F2 = Temperature correction factor (Figure A-2) F3 = Environmental service factor (Table A-5)

Table A-5 ENVIRONMENTAL SERVICE FACTOR, F3

Substance

Service Factor, F3

Crude Oil 0.50 Wet Natural Gas 0.50

Federally Regulated Dry Natural Gas 0.64 It should be noted the maximum recommended service temperatures, under continuous pressure service, for PolyPipe® is 150ºF (66ºC). However, for a non-pressure application, temperatures as high as 180ºF (82ºC) can be considered. In such cases, consult your PolyPipe® supplier for additional design assistance. Note: Compressed air service (greater than atmospheric pressure) can significantly shorten service life at temperatures above 73°F. PolyPipe® does not recommend its’ product for compressed air service for a service life greater than 5 years at 100oF. Further, PolyPipe® recommends all polyethylene piping in use for air service be buried. Refer to Recommendation “B”, published by PPI, for further information regarding the use of polyethylene piping for compressed air service. Critical Buckling In the design of a polyethylene piping system, external fluid pressure and/or internal vacuum may be treated comparably. In a non-supported application collapse of the pipe may be calculated from the equation1:

(3)

Where P = Critical buckling pressure, psi E = Modulus of elasticity, psi D = Outside diameter, inches t = Wall thickness, inches ν = Poisson’s ratio, dimensionless SF = Safety Factor This provides resistance to forces created by external fluid pressure and/or internal vacuum that may start collapse of a polyethylene pipe. Use of the long-term modulus of elasticity, 30,000 psi, instead of the instantaneous value of 125,000 psi, provides for a method of determining long-term distortion free operation. This calculation is accurate for thin wall pipes and becomes progressively more conservative for thicker walls. The values shown in Table A-7 on pages A-16 and A-17 were obtained empirically. Further information on earthloading is given in Section C.

1 Nayyar, Mohinder L. Ed. Piping Handbook. 6th Edition. New York: McGraw-Hill, Inc., 1992.

( ) SFtD

tvEP ⋅⎟⎟

⎠

⎞⎜⎜⎝

⎛−

⎟⎠⎞

⎜⎝⎛

−=

3

212

A-13PolyPipe12/05

A-14PolyPipe 12/05

A-15PolyPipe 12/05

Table A-6 INTERNAL PRESSURE RATINGS FOR POLYPIPE®

DR

Temp., °F / °C

Life Yrs. 7 7.3 9 9.3 11 13.5 15.5 17 21 26 32.5

1 368 351 276 266 221 177 152 138 110 88 70 psi 2.54 2.42 1.90 1.83 1.52 1.22 1.05 0.95 0.76 0.61 0.48 MPa

2 359 342 269 259 215 172 149 135 108 86 68 psi 2.48 2.36 1.86 1.79 1.48 1.19 1.03 0.93 0.74 0.59 0.47 MPa

5 347 331 260 251 208 167 144 130 104 83 66 psi 2.39 2.28 1.79 1.73 1.43 1.15 0.99 0.90 0.72 0.57 0.46 MPa

10 340 323 255 245 204 163 141 127 102 81 65 psi 2.34 2.23 1.76 1.69 1.41 1.12 0.97 0.88 0.70 0.56 0.45 MPa

20 330 314 248 239 198 158 137 124 99 79 63 psi 2.28 2.17 1.71 1.65 1.37 1.09 0.94 0.86 0.68 0.54 0.43 MPa

50 317 302 238 229 190 152 131 119 95 76 60 psi

50°/10°

2.19 2.08 1.64 1.58 1.31 1.05 0.90 0.82 0.66 0.52 0.41 MPa 1 309 295 232 224 186 148 128 116 93 74 59 psi 2.13 2.03 1.60 1.54 1.28 1.02 0.88 0.80 0.64 0.51 0.41 MPa

2 302 287 226 218 181 145 125 113 90 72 57 psi 2.08 1.98 1.56 1.50 1.25 1.00 0.86 0.78 0.62 0.50 0.39 MPa

5 292 278 219 211 175 140 121 109 88 70 56 psi 2.01 1.92 1.51 1.46 1.21 0.97 0.83 0.75 0.61 0.42 0.39 MPa

10 285 272 214 206 171 137 118 107 86 68 54 psi 1.97 1.88 1.48 1.42 1.18 0.94 0.81 0.74 0.59 0.47 0.37 MPa

20 277 264 208 200 166 133 115 104 83 67 53 psi 1.91 1.82 1.43 1.38 1.14 0.92 0.79 0.72 0.57 0.46 0.37 MPa

50 267 254 200 193 160 128 110 100 80 64 51 psi

75°/23°

1.84 1.75 1.38 1.33 1.10 0.88 0.76 0.69 0.55 0.44 0.35 MPa 1 251 239 188 181 150 120 104 94 75 60 48 psi 1.73 1.65 1.30 1.25 1.03 .083 0.72 0.65 0.52 0.41 0.33 MPa

2 244 233 183 177 147 117 101 92 73 59 47 psi 1.68 1.61 1.26 1.22 1.01 0.81 0.70 0.63 0.50 0.41 0.32 MPa

5 236 225 177 171 142 113 98 89 71 57 45 psi 1.63 1.55 1.22 1.18 0.98 0.78 0.68 0.61 0.49 0.39 0.31 MPa

10 231 220 173 167 139 111 96 87 69 55 44 psi 1.59 1.52 1.19 1.15 0.96 0.7 0.66 0.60 0.48 0.38 0.30 MPa

20 225 214 168 162 135 108 93 84 67 54 43 psi 1.55 1.48 1.16 1.12 0.93 0.74 0.64 0.58 0.46 0.37 0.30 MPa

50 216 206 162 156 130 104 89 81 65 52 41 psi

100°/38°

1.49 1.42 1.12 1.08 0.90 0.72 0.61 0.56 0.45 0.36 0.28 MPa 1 192 183 144 139 115 92 79 72 58 46 37 psi 1.32 1.26 0.99 0.96 0.79 0.63 0.54 0.50 0.40 0.32 0.26 MPa

2 187 178 140 135 112 90 77 70 56 45 36 psi 1.29 1.23 0.97 0.93 0.77 0.62 0.53 0.48 0.39 0.31 0.25 MPa

5 181 172 136 131 109 87 75 68 54 43 34 psi 1.25 1.19 0.94 0.90 0.75 0.60 0.52 0.47 0.37 0.30 0.23 MPa

10 177 168 133 128 106 85 73 66 53 42 34 psi 1.22 1.16 0.92 0.88 0.73 0.59 0.50 0.46 0.37 0.29 0.23 MPa

20 172 164 129 124 103 83 71 64 52 41 33 psi 1.19 1.13 0.89 0.86 0.71 0.57 0.49 0.44 0.36 0.28 0.23 MPa

50 165 157 124 120 99 79 68 62 50 40 31 psi

125°/52°

1.14 1.08 0.86 0.83 0.68 0.54 0.47 0.43 0.34 0.28 0.21 MPa

Note: Tables for internal and external pressure ratings for PE3408 are based on gases and liquids that are non-aggressive to the polyethylene. For further information on chemical resistance of PolyPipe®, see Section E, "Chemical Resistance."

A-16PolyPipe 12/05

Table A-6 (cont) INTERNAL PRESSURE RATINGS FOR POLYPIPE®

DR

Temp., °F / °C

Life, years 7 7.3 9 9.3 11 13.5 15.5 17 21 26 32.5

1 156 148 117 113 93 75 64 58 47 37 30 psi 1.08 1.02 0.81 0.78 0.64 0.52 0.44 0.40 0.32 0.26 0.21 MPa

2 151 144 113 110 90 72 62 57 45 36 29 psi 1.04 0.99 0.78 0.76 0.62 0.50 0.43 0.39 0.31 0.25 0.20 MPa

5 147 139 110 106 88 70 60 55 44 35 29 psi 1.01 0.96 0.76 0.73 0.61 0.48 0.41 0.38 0.30 0.24 0.20 MPa

10 142 135 106 103 85 68 58 53 43 34 28 psi 0.98 0.93 0.73 0.71 0.59 0.47 0.40 0.37 0.30 0.23 0.19 MPa

20 140 132 104 101 83 67 57 52 42 33 27 psi 0.97 0.91 0.72 0.70 0.57 0.46 0.40 0.36 0.29 0.23 0.19 MPa

50 134 127 100 97 80 64 55 50 40 32 26 psi

140°/60°

0.92 0.88 0.69 0.67 0.55 0.44 0.38 0.35 0.28 0.22 0.18 MPa

Table A-7

EXTERNAL PRESSURE RATINGS FOR POLYPIPE® (for non-supported application)

DR

Temp., °F / °C

Life, years 7 7.3 9 9.3 11 13.5 15.5 17 21 26 32.5

Day 221.1 201.0 150.7 142.7 110.6 68.3 48.2 28.1 14.1 8.0 4.0 psi 1.52 1.39 1.04 0.98 0.76 0.47 0.33 0.19 0.10 0.06 0.03 MPa

Month 154.0 140.0 105.0 99.4 77.0 47.6 33.6 19.6 9.8 5.6 2.8 psi 1.06 0.97 0.72 0.69 0.53 0.33 0.23 0.14 0.07 0.04 0.02 MPa

Year 132. 120.0 90.0 85.2 66.0 40.8 28.8 16.8 8.4 4.8 2.4 psi 0.91 0.83 0.62 0.59 0.46 0.28 0.20 0.12 0.06 0.03 0.02 MPa

2 Years 123.2 112.0 84.0 79.5 61.6 38.1 26.9 15.7 7.8 4.5 2.2 psi 0.85 0.77 0.58 0.55 0.42 0.26 0.19 0.11 0.05 0.03 0.02 MPa

5 Years 117.7 107.0 80.6 76.0 58.9 36.4 25.7 15.0 7.5 4.3 2.1 psi 0.81 0.74 0.55 0.52 0.41 0.25 0.18 0.10 0.05 0.03 0.01 MPa

10 Years 114.4 104.0 78.0 73.8 57.2 35.5 25.0 14.6 7.3 4.2 2.1 psi 0.79 0.72 0.54 0.51 0.39 0.24 0.17 0.10 0.05 0.03 0.01 MPa

50 Years 110.0 100.0 75.0 71.0 55.0 34.0 24.0 14.0 7.0 4.0 2.0 psi

50°/10°

0.76 0.68 0.52 0.49 0.38 0.23 0.17 0.10 0.05 0.03 0.01 MPa Day 176.0 164.8 134.7 124.6 98.5 60.3 42.2 24.1 13.1 7.0 3.6 psi

1.22 1.14 0.93 0.86 0.68 0.42 0.29 0.17 0.09 0.05 0.02 MPa Month 123.2 114.8 93.8 86.8 68.6 42.0 29.4 16.8 9.1 4.9 2.5 psi

0.85 0.79 0.65 0.60 0.47 0.29 0.20 0.12 0.06 0.03 0.02 MPa Year 105.6 98.4 80.4 74.4 58.8 36.0 25.2 14.4 7.8 4.2 2.2 psi

0.73 0.68 0.55 0.51 0.41 0.25 0.17 0.10 0.05 0.03 0.02 MPa 2 Years 98.6 91.8 75.0 69.4 54.9 33.6 23.5 13.4 7.3 3.9 2.0 psi

0.68 0.63 0.52 0.48 0.38 0.23 0.16 0.09 0.05 0.03 0.01 MPa 5 Years 94.2 87.7 71.7 66.3 52.4 32.1 22.5 12.8 7.0 3.7 1.9 psi

0.65 0.60 0.49 0.46 0.36 0.22 0.16 0.09 0.05 0.03 0.01 MPa 10 Years 91.5 85.3 69.7 64.5 51.0 31.2 21.8 12.5 6.8 3.6 1.9 psi

0.63 0.59 0.48 0.44 0.35 0.22 0.15 0.09 0.05 0.02 0.01 MPa 50 Years 88.0 82.0 67.0 62.0 49.0 30.0 21.0 12.0 6.5 3.5 1.8 psi

75°/23°

0.61 0.57 0.46 0.43 0.34 0.21 0.14 0.08 0.04 0.02 0.01 MPa Note: Tables for internal and external pressure ratings for PE3408 are based on gases and liquids that are non-aggressive to the polyethylene. For further information on chemical resistance of PolyPipe®, see Section E, "Chemical Resistance."

A-17PolyPipe 12/05

Table A-7 (cont)

EXTERNAL PRESSURE RATINGS FOR POLYPIPE®

DR

Temp., °F / °C

Life, years 7 7.3 9 9.3 11 13.5 15.5 17 21 26 32.5

Day 152.8 140.7 110.6 104.5 82.4 48.2 34.2 20.1 10.1 6.0 3.0 psi 1.05 0.97 0.76 0.72 0.57 0.33 0.24 0.14 0.07 0.04 0.02 MPa

Month 106.4 98.0 77.0 72.8 57.4 33.6 23.8 14.0 7.0 4.2 2.1 psi 0.73 0.68 0.53 0.50 0.40 0.23 0.16 0.10 0.05 0.03 0.01 MPa

Year 91.2 84.0 66.0 62.4 49.2 58.8 20.4 12.0 6.0 3.6 1.8 psi 0.63 0.58 0.46 0.43 0.34 0.20 0.14 0.08 0.04 0.02 0.01 MPa

2 Years 85.1 78.4 61.6 58.2 45.9 26.9 19.0 11.2 5.6 3.4 1.7 psi 0.59 0.54 0.42 0.40 0.32 0.19 0.13 0.08 0.04 0.02 0.01 MPa

5 Years 81.3 74.9 58.9 55.6 43.9 25.7 18.2 10.7 5.4 3.2 1.6 psi 0.56 0.52 0.41 0.38 0.30 0.18 0.13 0.07 0.04 0.02 0.01 MPa

10 Years 79.0 72.8 57.2 54.1 42.6 25.0 17.7 10.4 5.2 3.1 1.6 psi 0.54 0.50 0.39 0.37 0.29 0.17 0.12 0.08 0.04 0.02 0.01 MPa

50 Years 76.0 70.0 55.0 52.0 41.0 24.0 17.0 10.0 5.0 3.0 1.5 psi

100o/38°

0.52 0.48 0.38 0.36 0.28 0.17 0.12 0.07 0.03 0.02 0.01 MPa Day 120.6 108.5 88.4 82.4 68.3 38.2 26.1 16.1 9.0 4.6 2.4 psi

0.83 0.75 0.61 0.57 0.47 0.26 0.18 0.11 0.06 0.03 0.02 MPa Month 84.0 75.6 61.6 57.4 47.6 26.6 18.2 11.2 6.3 3.2 1.7 psi

0.58 0.52 0.42 0.40 0.33 0.18 0.13 0.08 0.04 0.02 0.01 MPa Year 72.0 64.8 52.8 49.2 40.8 22.8 15.6 9.6 5.4 2.8 1.4 psi

0.50 0.45 0.36 0.34 0.28 0.16 0.11 0.07 0.04 0.02 0.01 MPa 2 Years 67.2 60.5 49.3 45.9 38.1 21.3 14.6 9.0 5.0 2.6 1.3 psi

0.46 0.42 0.34 0.32 0.26 0.15 0.10 0.06 0.03 0.02 0.01 MPa 5 Years 62.4 57.8 47.1 43.9 36.4 20.3 13.9 8.6 4.8 2.5 1.3 psi

0.44 0.40 0.32 0.30 0.25 0.14 0.10 0.06 0.03 0.02 0.01 MPa 10 Years 62.4 56.2 48.8 42.6 35.4 19.8 13.5 8.3 4.7 2.4 1.2 psi

0.43 0.39 0.34 0.29 0.24 0.14 0.09 0.06 0.03 0.02 0.01 MPa 50 Years 60.0 54.0 44.0 41.0 34.0 19.0 13.0 8.0 4.5 2.3 1.2 psi

125°/52°

0.41 0.37 0.30 0.58 0.23 0.13 0.09 0.06 0.03 0.02 0.01 MPa Day 104.5 94.5 76.4 72.4 58.3 32.2 22.1 14.1 7.4 4.0 2.0 psi

0.72 0.65 0.53 0.50 0.40 0.22 0.15 0.10 0.05 0.03 0.01 MPa Month 72.8 65.8 53.2 50.4 40.6 22.4 15.4 9.8 5.2 2.8 1.4 psi

0.50 0.45 0.37 0.35 0.28 0.15 0.11 0.07 0.04 0.02 0.01 MPa Year 62.4 56.4 45.6 43.2 34.8 19.2 13.2 8.4 4.4 2.4 1.2 psi

0.43 0.39 0.31 0.30 0.24 0.13 0.09 0.06 0.03 0.02 0.01 MPa 2 Years 58.2 52.6 42.6 40.3 32.5 17.9 12.3 7.8 4.1 2.2 1.1 psi

0.40 0.36 0.29 0.28 0.22 0.12 0.08 0.05 0.03 0.02 0.01 MPa 5 Years 55.6 50.3 40.7 38.5 31.0 17.1 11.8 7.5 4.0 2.1 1.1 psi

0.38 0.35 0.28 0.27 0.21 0.12 0.08 0.05 0.03 0.01 0.01 MPa 10 Years 54.1 48.9 39.5 37.4 30.2 16.6 11.4 7.3 3.8 2.1 1.0 psi

0.37 0.34 0.27 0.26 0.21 0.11 0.08 0.05 0.03 0.01 0.01 MPa 50 Years 52.0 47.0 38.0 36.0 29.0 16.0 11.0 7.0 3.7 2.0 1.0 psi

150°/65°

0.36 0.32 0.26 0.25 0.20 0.11 0.08 0.05 0.06 0.01 0.01 MPa Note: Tables for internal and external pressure ratings for PE3408 are based on gases and liquids that are non-aggressive to the polyethylene. For further information on chemical resistance of PolyPipe®, see Section E, "Chemical Resistance."

A-18PolyPipe 12/05

VACUUM OR EXTERNAL PRESSURE SYSTEM

A piping system can be subjected to a positive external pressure or vacuum as opposed to the more usual positive internal pressure situation. In most cases this occurs by design, as in a water suction line, but it can also occur in an unexpected manner. For instance, a system that has a high point in the down slope side of the pipeline can result in a flow velocity greater than the velocity on the uphill side. In other applications, there may be both vacuum and external pressure applied to the system. This condition can occur if a pump suction line is buried with significant external load above the top of the pipe. Both of these factors are additive and should be considered in the design of the piping system. In either situation, the effects of external pressure or vacuum conditions must be considered in the design. Pipe buckling can occur in extreme cases, but can be prevented by correctly designing the system. In the event that buckling should occur, it is generally not a catastrophic failure. Buckling occurs as a gradual deflection of the pipe to an out-of-round condition that will progressively worsen to the point of becoming totally flat. Since buckling occurs without cracking or splitting the pipe wall, the pipe can be restored to its original round condition. This can be accomplished by applying an internal pressure for a short period of time. The cause of the buckling should be identified and corrected. Safe external pressures for PolyPipe® are given in Table A-7 for a series of temperatures. These values are based on various life expectancies for applications using water or fluids having similar compatibility with polyethylene. In some situations, vacuums and/or external loads occur for a relatively short duration. By estimating the duration of the load and applying the time correction factors, Table A-8, the designer may match the pipe DR (Dimension Ratio) to the particular application. Thinner wall pipe is usually capable of handling short duration loads. These time correction factors are used in the calculation of the values represented in Table A-7 on pages A-16 and A-17. External loading is explained in more detail in Section C.

Table A-8 TIME CORRECTION FACTOR

Time

Time Correction Factor

Day 2.01 Month 1.40 Year 1.20

2 Years 1.12 5 Years 1.07 10 Years 1.04 50 Years 1.00

Example: Calculate the external pressure for DR 26 pipe for one-month duration with an estimated 4.0 psi (0.02 Mpa) external pressure at 75oF (23oC). From Table A-7, external pressure at 50 years is 3.5 psi (0.02 MPa) x time correction factor, 1.40 = 4.90 psi (0.03 MPa) capabilities.

NOTICE: The data contained herein is a guide to the use of PolyPipe® polyethylene pipe and fittings and is believed to be accurate and reliable. However, general data does not adequately cover specific applications, and its suitability in particular applications should be independently verified. In all cases, the user should assume that additional safety measures might be required in the safe installation or operation of the project. Due to the wide variation in service conditions, quality of installation, etc., no warranty or guarantee, expressed or implied, is given in conjunction with the use of this material.

B-1PolyPipe 12/05

FLUID FLOW

The rate at which fluid flows through a piping system is an important factor in designing the system. Factors affecting fluid flow can include the following: density, pressure (including pressure loss), inside diameter of the pipe, and any additional resistance factors within the system such as fittings. PolyPipe® has an extremely smooth inside surface resulting in a very low coefficient of friction and a minimal loss of head pressure due to frictional losses as compared to other piping materials. The inside surface experiences virtually no deterioration due to corrosion. Beneficial properties of the smooth bore of the polyethylene pipe are maintained throughout its service life. In view of these advantages, it is often possible to utilize a polyethylene pipe of a smaller inside diameter than other piping products. The maximum allowable water velocity in a thermoplastic piping system is a function of the design of a specific system and its operating conditions. Per PPI Technical Report #14, “In general, design velocities of 5 - 10 feet/sec are considered to be normal.” As noted, these velocities are recommended for water and will vary depending on the fluid medium and inside diameter of the pipe. Recommended velocities for different fluid properties are given below in Table B-1. Additional information for slurry type applications is addressed in Section H.

Table B-1

RECOMMENDED LIQUID VELOCITIES

Recommended Velocity Water and Similar Viscous Liquids Viscous Liquids

Pipe Size Pump

Suction* Pump

Discharge Gravity Drain

System Pump

Suction* Pump

Discharge

3 - 10 inches 1 - 4 feet/sec 3 – 10 feet/sec 3 - 5 feet/sec .05 - 2 feet/sec 3 - 5 feet/sec (76 - 254 mm) (30 - 122 cm/sec) (91 - 300 cm/sec) (91 - 152 cm/sec) (15 - 61 cm/sec) (91 - 152 cm/sec)

10 - 28 inches 3 - 6 feet/sec 4 – 10 feet/sec 4 - 8 feet/sec 1 - 4 feet/sec 4 - 6 feet/sec (254 - 711 mm) (91 - 183 cm/sec) (122 - 400 cm/sec) (122 - 244 cm/sec) (30 - 122 cm/sec) (122 - 183 cm/sec)

28 - 54 inches 5 - 8 feet/sec 6 - 12 feet/sec 6 - 10 feet/sec 2 - 5 feet/sec 5 - 7 feet/sec (711 - 1372 mm) (152 - 244 cm/sec) (183 - 366 cm/sec) (183 - 305 cm/sec) (61 - 152 cm/sec) (152 - 213 cm/sec)

*It is important in the selection of the pipe size that the designated pump suction velocity be lower than the discharge velocity.

PRESSURE DROP

A fluid is defined as "a substance which when in static equilibrium cannot sustain tangential or shear forces." Three types of forces that may act on a body are shear, tensile and compressive. Shear and tensile forces on fluids are not addressed in this Guide. Compressive forces, which result in pressure, are considered due to the importance in the design of piping system capabilities. Volumetric flow, Q, can be determined from the continuity equation4 = A • V. Modified for flow in gallons per minute, this is:

(4)

or

(5)

Where Q = Volumetric flow, gpm V = Velocity, ft/sec d = Inside diameter, inches

EXAMPLE: If the required water flow rate for a system is 2000 gpm and the flow velocity is to be maintained below 8 ft/s, what is the pipe diameter?

FRICTIONAL PRESSURE LOSS The total pressure drop in a system is the sum of pressure losses due to friction, fittings and elevation changes. Pressure loss due to friction in the pipe is calculated using the Hazen-Williams formula1. This applies to systems pumping water and fluids of like viscosities. The Hazen-Williams formula is:

(6)

Where fPΔ = Pressure loss due to friction, psi per 100 feet C = Hazen-Williams Flow Factor Coefficient* Q = Volumetric flow rate, gpm d = Inside diameter, inches *PolyPipe® recommends a value of 150 for C based upon information from Plastics Pipe Institute Technical Report #14, Water Flow Characteristics of Thermoplastic Pipe. For further information, please reference this article (www.plasticpipe.org). It should be noted the pipe sizes quoted in the figures are minimum bore sizes and the specific outside diameter of the pipe can be found from the pipe dimensions located in Section A. The Hazen-Williams formula can be used to calculate any one of the following variables: volumetric flow rate (Q), velocity (V), inside pipe diameter (d) or frictional pressure loss (ΔPf). Additional values for Hazen-Williams Flow Factor Coefficients are shown in Table B-2.

4 Larock, B.E., Jeppson, R.W. , Watters, G.Z. Hydraulics of Pipeline Systems. Boca Raton: CRC Press, 2000. 1 Nayyar, Mohinder L. Ed. Piping Handbook. 6th Edition. New York: McGraw-Hill, Inc., 1992.

inches 10.18448.2

2000d =⋅

=

2448.2 dVQ ⋅⋅=

VQd

⋅=

448.2

86.485.1

85.1453dCQPf ⋅

⋅=Δ

B-2PolyPipe 12/05

Table B-2 HAZEN-WILLIAMS COEFFICIENTS FOR FLOW IN VARIOUS PIPES

PIPE DESCRIPTION "C" VALUE

PolyPipe® HDPE 150 Very smooth and straight steel, glass 130-140 New cement-lined ductile iron 130 Smooth wood and wood stave 120 New riveted steel, cast iron 110 Old cast iron 95 Old pipes in bad condition 60-80 Small pipes, badly corroded 40-50

ELEVATION PRESSURE LOSS/GAIN

The Hazen-Williams formula is used to establish only the pressure losses due to friction in the pipe. If there is a change in elevation, it is necessary to calculate the change in pressure due to elevation changes. The change in pressure may be either a positive change (downhill) or negative (uphill). In a line with an elevation change without a change in pipe diameter, the pressure loss can be calculated as follows:

(7)

Where ΔPe = Change in pressure due to elevation change, psi h2 = High point elevation, feet h1 = Low point elevation, feet ρ = Density of fluid, lbs/ft3

PRESSURE LOSS IN FITTINGS Any calculation of the pressure drop in a piping system cannot be made accurately without consideration of the loss in pressure due to the presence of fittings in the system. The fluid flow, when encountering a fitting, is subjected to change in direction and the resultant degree of initiation of turbulence, or at least an interruption in the desirable steady flow condition which exists in the straight run of pipe, is an increase in head loss or pumping pressure. Due to the geometry and variance in flow conditions through the fitting, the exact pressure loss cannot be calculated in any practical sense. The pressure loss is calculated by expressing the fitting as an equivalent length of pipe expected to produce the same pressure loss. The values shown in Table B-3 have been derived to some extent by experimentation, but are to a greater extent the result of a general industry consensus (PPI Technical Report #14).

( )144

12 hhPe−

=Δ ρ

B-3PolyPipe 12/05

Table B-3 PRESSURE DROP IN FITTINGS

TYPE OF FITTING EQUIVALENT LENGTH OF PIPE*, ft

90° Elbow, molded 16D 90° Elbow, mitered 24D 60° Elbow 16D 45° Elbow, molded 16D 45° Elbow, mitered 12D Running Tee 20D Branch Tee 60D Gate Valve, full open 8D Butterfly Valve 3”-14” (76-356 mm) 40D 114” (356 mm) and larger 30D Swing Check Valve 100D Ball Valve, full bore, full open 3D

*NOTE: D is the inside diameter of the pipe in feet.

EXAMPLE: A running tee has an equivalent length of 20D. For an 18” (457 mm) DR11 line, calculate the equivalent length of pipe for the fitting to account for the pressure loss. From page A-6, the nominal inside diameter of 18” DR11 is 14.60 inches. 14.60” x 20 = 292 inches or 24.3 feet Therefore, a total of 24.3 feet is added to the total line length to account for the additional pressure loss created by the fitting.

TOTAL PRESSURE LOSS

The total pressure required to maintain the flow rate can be calculated by summing pressure losses calculated using the Hazen-Williams for frictional pressure loss in the pipe, Equation (7) for elevation changes and Table B-3 for fitting pressure losses.

(8)

B-4PolyPipe 12/05

fittingsefT PPPP Δ+Δ+Δ=Δ

GRAVITY FLOW

The Manning equation1 is the most commonly accepted approximation for gravity flow.

(9)

Where V = Average flow velocity, ft/sec R = Hydraulic radius, feet S = Slope of pipe, feet per foot n = Manning flow coefficient, 0.010 The Manning flow coefficient (n) for PolyPipe® is approximately 0.009. However, a reliable, conservative approximation generally used is 0.010. The hydraulic radius can be determined from the following formula:

(10)

Where R = Hydraulic radius, feet f = Fullness factor d = Inside diameter, feet

Table B-4 FULLNESS FACTORS

h ID f A h

ID f A

0.05 0.0326 0.0147 0.55 0.2649 0.4426 0.10 0.0636 0.0409 0.60 0.2776 0.4920 0.15 0.0929 0.0739 0.65 0.2881 0.5404 0.20 0.1206 0.1118 0.70 0.2962 0.5872 0.25 0.1466 0.1535 0.75 0.3017 0.6319 0.30 0.1710 0.1982 0.80 0.3042 0.6736 0.35 0.1935 0.2450 0.85 0.3033 0.7115 0.40 0.2143 0.2934 0.90 0.2980 0.7445 0.45 0.2331 0.3428 0.95 0.2864 0.7707 0.50 0.2500 0.3927 1.00 0.2500 0.7854

Once the flow velocity has been determined, the volumetric flow rate can be calculated by use of the following formula:

(11)


2dAVQ ⋅⋅=

nSRV

5.0667.0486.1 ⋅⋅=

dfR ⋅=

B-5PolyPipe 12/05

Where Q = Volumetric flow rate, ft3/sec V = Velocity, ft/sec d = Inside diameter, feet A = Area factor from Table B-4

or

(12)

Where Q = Volumetric flow rate, gpm For full flow applications, the volumetric flow rate can be determined by use of the following formula:

(13)

Where Q = Volumetric flow rate, gpm n = Manning coefficient, 0.010 d = Inside diameter, inches S = Slope, feet per foot

2449 dAVQ ⋅⋅⋅=

5.0667.2275.0 Sdn

Q ⋅⋅=

B-6PolyPipe 12/05

PRESSURE SURGE AND WATER HAMMER

Widespread usage of polyethylene pipe in liquid flow necessitates a better understanding of actions and reactions in mass flow that could affect the system. As water is a liquid, and at substantial velocities almost acts like a solid, it behaves in a complex manner when accelerating or decelerating. This moving water column inside a pipe has available active kinetic energy. This energy can be calculated from its mass and velocity. A change in the column velocity causes an energy change that manifests itself as a pressure change. This pressure change, or surge pressure, is commonly known as "water hammer." Water hammer is better described as hydraulic transient pressure and is a sudden increase or decrease in pressure due to changes in the velocity of flowing fluid in a pipeline. Air entrained in a piping system over normal rolling terrain can cause water hammer. Even if proper filling techniques are utilized and all air is displaced, entrained air will separate and collect in pockets in the "humps" in the pipeline. Significant pressures are generated when the air pockets are suddenly released. The use of air relief valves at the high points can alleviate this problem. An abrupt blockage in a moving column of water creates an increase in pressure on the upstream side and a negative pressure on the downstream side of the block. The magnitude of these pressures is relative to the velocity of the fluid, mass of the fluid and speed the blockage occurs. The forces required to bring this column of water to rest are the forces for friction and the hoop stress imposed on the pipe wall. Therefore, the stress in the pipe wall is increased by the magnitude of the surge and the total stress is normal operating stress (pressure) plus the surge stress (pressure). On the downstream side of a block the water column may create a vacuum. Depending on the velocity of the column, it may separate and be drawn back together. Vacuum in this condition does not normally detrimentally affect the pipe unless column separation does occur. In that case, extremely high positive pressures can be generated when the void re-closes and the two column faces collide. Water hammer in a piping system is a pressure wave that is set up due to a change in velocity of the liquid and the wave may move through the column at a velocity of up to 4500 ft/sec, depending upon the piping material. The magnitude, ΔP, of this pressure wave can be calculated from the following equation1:

(14)

Where ΔP = Surge pressure, psi ΔV = Change in velocity, ft/sec g = Acceleration due to gravity, 32.2 ft/sec2 ρ = Density of fluid, lb/ft3 S = Wave velocity, ft/sec The value calculated by using Equation (14) may have either a resultant positive or negative pressure wave. This resultant force, when superimposed on the existing operating pressure curve, will either decrease or increase from the normal operating pressure. Where S, the wave velocity, can be calculated by the following formula1:

(15)

Where E = Instantaneous modulus of elasticity of material, lbs/ft2 1 Nayyar, Mohinder L. Ed. Piping Handbook. 6th Edition. New York: McGraw-Hill, Inc., 1992.

2/1

''

⎥⎥⎥⎥

⎦

⎤

⎢⎢⎢⎢

⎣

⎡

⎟⎟⎠

⎞⎜⎜⎝

⎛⎟⎠⎞

⎜⎝⎛ ⋅

+⋅

⋅=

tdEE

g

EESρ

B-7PolyPipe 12/05

VSg144

P ΔρΔ ⋅⋅⋅

=

E’ = Bulk modulus of fluid, lbs/ft2 d = Inside diameter, feet ρ = Density of fluid, lb/ft3 g = Acceleration due to gravity, 32.2 ft/sec2 t = Pipe wall thickness, feet Due to the elastic properties of polyethylene, a significant amount of pressure surge is absorbed through expansion. This elasticity provides for reduction of the shock wave initially and dissipation of the wave. Per AWWA C-906, a system operating below the pressure class rating is capable of handling a surge capacity in accordance with the following: 1. Recurring Pressure Surge: The total of the maximum working pressure and maximum recurring pressure

surge may be no greater than 1.5 times the pipe’s nominal pressure class (PC). 2. Occasional Pressure Surge: The total of the maximum working pressure and maximum occasional pressure

surge may be no greater than 2 times the pipe’s nominal pressure class (PC). Since water hammer surges are produced due to a change in velocity, the proper control of valves may eliminate or minimize this effect. In order to minimize or eliminate water hammer, the flow must not be shut off any faster than it takes a pressure wave to be initiated at the beginning of valve closing and returning to the valve again. This by definition is considered the critical time (Tcr)1 that is defined as the longest elapsed time before final flow stoppage that still permits the maximum pressure to occur.

(16)

Where Tcr = Propagation time, seconds

sv = Speed of sound through commodity, ft/sec L = Length of pipeline, feet

Since most valves do not cut off the flow rate proportionately to the valve-stem travel, it is significant to base timing of valve closure on effective closing timing. The effective closing timing in most applications is determined as one-half of the actual closing time. This is the value that should be used in water hammer calculations. The most important aspect to recognize in the design of the system is to remember water hammer surge can occur and methods of protecting the system and minimizing effect need to be addressed. This can be accomplished by the installation of equipment including the following:

Pressure relief valves Control closing check valves Surge arrestors Vacuum air relief valves Surge tanks Manually operated gate valves

In summary, surges are the result of a change in velocity within the system. This change in velocity is directly related to the change in pressure for the system (negative or positive). Water hammer surges can be avoided by eliminating sudden changes in velocity within the system. By taking the necessary precautionary steps during initial filling and testing of the pipeline, a significant number of surge problems can be eliminated.



scr v

LT ⋅=

2

B-8PolyPipe 12/05

EARTHLOADING

PolyPipe®, due to its flexibility, will deflect when it is buried. The degree of deflection will depend upon the soil conditions, burial conditions, trench width, and the depth of burial. The degree of deflection of the pipe is limited by the soil around its periphery, especially in the lateral direction. When the soil compacts around the pipe, there is a supportive effect from the soil itself, and as compaction occurs, there is soil friction and cohesion over the pipe that reduces the direct load on the pipe. PolyPipe®, as do other flexible conduits, depends on the surrounding soil for support, and has to be considered as one component in a pipe/soil system. The presence of the soil arch and the support derived from the lateral movement limitations are highly beneficial to the efficiency of the system. Therefore, the flexibility of PolyPipe® is the major reason for these advantages. As has been stated, the durability of polyethylene is the reason for its resistance to high levels of mechanical abuse, and this is no less true for buried systems where forced deflections may occur due to subsidence, washout and settlement. External loading analysis must be conducted to determine the application's feasibility. There are two loading calculations necessary when designing or engineering below ground applications of PolyPipe®. These calculations are ring deflection and wall buckling. Wall crushing, calculated using the allowable compressive strength of the PE material, is usually not critical when using solid wall PolyPipe®, as ring deflection and wall buckling are predominant parameters. RING DEFLECTION PolyPipe®, when buried in loose soil conditions, will exhibit the tendency to deflect, called ring deflection. Listed below are the recommended maximum allowable design limits for ring deflection of PolyPipe® for the different available Dimension Ratios (DR).

Table C-1 Design Limits for Ring Deflection

DR Safe Deflection, % of Diameter

32.5 8.0 26 7.0 21 6.0 17 5.0

Figure C-1

ΔX

D

W

C-1PolyPipe 12/05

PolyPipe®, due to its inherent physical properties of flexibility, resilience and toughness can withstand significant deflection without failure. It can be flattened without causing a fracture of the pipe wall. However, this condition is unacceptable as far as service is concerned. A deflection of 15% would be acceptable for a butt fused polyethylene system, although a reduction in flow would be noted. It would also be difficult to utilize conventional cleaning equipment with this severity of deflection. Ring deflection resulting in hydraulic flow area reductions should be taken into account when engineering the flow characteristics. Refer to Table C-2 for the percentage of area reduction based on percent of ring deflection.

Table C-2

AREA REDUCTION DUE TO RING DEFLECTION

Ring Deflection, % Area Reduction, %

2 0.04 4 0.16 5 0.25 6 0.36 8 0.64

10 1.00 12 1.44 14 1.96 15 2.25 16 2.56

In calculating the soil load placed on a buried pipe, the designer must be able to calculate to some degree of accuracy the type and condition of the backfill material. Saturated clay would be more difficult to place and adequately compact than would coarse granular material that would not stick together. It is important in the pipe/soil system that the backfill material utilized for haunching and initial backfill (see Installation, Section F, for explanation of terminology) be granular and non-cohesive, free of debris, organic matter, frozen earth and rocks larger than 1½ inch in diameter. This material can be described as Class I or II of ASTM D2321 "Angular ¼ to 1½ inch Graded Stone, Slag, Cinders, Crushed Shells and Stone or Sands and Gravel Containing Small Percentages of Fines, Generally Granular and Non-Cohesive, Wet or Dry." This material can easily be worked into the pipe haunch, and compacted in approximately 4-6 inch lifts. To determine the ring deflection of externally loaded PolyPipe®, you must first determine the earthload in pounds per linear inch of pipe by use of the following modified Marston formula5:

(17)

Where W = Earthload per unit length of pipe, lbs/in Cd = Trench Coefficient, (dimensionless) (See Figure C-2) ρ = Soil density, lbs/ft3 D = Outside diameter, inches Bd = Trench width at top of pipe, feet

5 Moser, A.P. Buried Pipe Design. 2nd Edition. New York: McGraw-Hill, 2001.

144DBCW dd ⋅⋅⋅

=ρ

C-2PolyPipe 12/05

C-3PolyPipe 12/05

Table C-3 CLASSIFICATION OF BACKFILL MATERIAL

PER ASTM D2321*

Class Comments Class I - Angular graded stone, ¼” to 1½”, including a number of fill materials that have regional significance such as coral, slag, cinders, crushed stone, crushed gravel and crushed shells.

100 - 200 pounds per cubic foot. Pipe sizes less than 10” should limit maximum particle size to ½” to ¾” for ease of placement.

Class II - Coarse sands and gravel with maximum particle size of 1½”, including variously graded sands and gravel containing small percentages of fines, generally granular and non-cohesive, wet or dry.

110 - 130 pounds per cubic foot. Pipe sizes less than 10” should limit maximum particle size to ½” to ¾” inch for ease of placement.

Class III - Fine sand and clay gravel, including fine sands, sand-clay mixtures, and gravel-clay mixtures.

140 - 150 pounds per cubic foot.

Class IV - Silt, silty clays, and clays, including inorganic clays and silts of medium to high plasticity and liquid limits.

150 - 180 pounds per cubic foot.

Class V - Includes organic soils as well as soils containing frozen earth, debris, rocks larger than 1½” in diameter, and other foreign materials.

Not recommended for backfill except in the final backfill zone.

* For further classification of soils the designer may want to review ASTM D2487, "Standard Test Method for Classification of Soil for Engineering Purposes."

Figure C-2 TRENCH COEFFICIENT, Cd

DEPENDENT ON SOIL TYPE AND DITCH CONFIGURATION

In general practice, the trench width can be kept to a minimum of six inches per side greater than the pipe diameter itself. Although this may seem narrow in comparison to trenching of conventional materials, it must be noted that PolyPipe® can be pre-assembled above ground and later placed into the trench. The trench width should be maintained as narrow as possible as the soil loading on the pipe is a relationship of the trench width.

The linear deflection of the pipe can be calculated from the following modified Spangler equation6:

(18)

Where Δ x = Horizontal deflection or change in diameter, inches

Dl = Deflection lag factor, PolyPipe® recommends 1.0 (dimensionless) K = Bedding constant, PolyPipe® recommends 0.1 (dimensionless) W = Earthload, lbs/inch (See Equation (17)) E = Modulus of elasticity of pipe, 30,000 psi E’ = Soil modulus, psi DR = Dimension ratio, (dimensionless)

* For further values of K see reference. The percent deflection can be calculated by use of the following formula6:

(19)

Where d = Percent deflection, % Δ x = Horizontal deflection, inches (See Equation (18)) D = Outside diameter, inches

Table C-4 TYPICAL SOIL MODULUS VALUES (PSI)

Type of Soil

Depth of Cover

Standard AASHTO relative compaction

ft m 85% 90% 95% 100%

Fine-grained soils with less than 0-5 0-1.5 500 700 1000 1500 25% sand content (CL, ML, CL-ML) 5-10 1.5-3.1 600 1000 1400 2000 10-15 3.0-4.6 700 1200 1600 2300 15-20 4.6-6.1 800 1300 1800 2600 Coarse-grained soils with fines 0-5 0-1.5 600 1000 1200 1900 (SM., SC) 5-10 1.5-3.0 900 1400 1800 2700 10-15 3.0-4.6 1000 1500 2100 3200 15-20 4.6-6.1 1100 1600 2400 3700 Coarse-grained soils with little or no 0-5 0-1.5 700 1000 1600 2500 fines (SP, SW, GP, GW) 5-10 1.5-3.0 1000 1500 2200 3300

10-15 3.0-4.6 1050 1600 2400 3600 15-20 4.6-6.1 1100 1700 2500 3800

6 Plastics Pipe Institute. Underground Installation of Polyethylene Pipe, 1996.

( )'061.0

132

3 EDR

EWKDx l

+⎟⎟⎠

⎞⎜⎜⎝

⎛−

⋅⋅=Δ

100⋅Δ

=Dxd

C-4PolyPipe 12/05

Values of modulus of soil reaction, E' (psi) based on depth of cover, type of soil, and relative compaction. Soil type symbols are from the United Classifications System. Source: Hartley, James D. and Duncan, James M., "E' and its Variation with Depth," Journal of Transportation, Division of ASCE, Sept. 1987.

WALL BUCKLING PolyPipe®, when buried in dense soil conditions and subjected to excessive external loading, will exhibit the tendency of wall buckling. As seen in Figure C-3, wall buckling is a longitudinal wrinkle that usually occurs between the 10:00 and 2:00 positions. Wall buckling should become a design consideration when the total vertical load exceeds the critical buckling stress of PolyPipe®.

Figure C-3

Vertical loading can be determined by the summation of the calculated dead load (load resulting from backfill overburden and static surface loads) and live load (loads resulting from cars, trucks, trains, etc.). BACKFILL LOAD1

(20)

Where Pb = Backfill load, psi ρsoil = Backfill density, lbs/ft3 H = Height of backfill above pipe, feet

SURFACE LOAD Surface loads are those forces exerted by permanent structures in close proximity to buried PolyPipe®. These loads can be buildings, storage tanks, or other structures of significant weight that could add to the backfill loading. The force exerted on PolyPipe® by structural surface loads can be approximated by use of the following Boussinesq17 formulation:

(21)

Where Ps = Surface load on pipe, psi L = Static surface load, lbs. z = Vertical distance from top of pipe to surface load level, feet R = Straight line distance from the top of pipe to surface load, feet

Where,

1 Nayyar, Mohinder L. Ed. Piping Handbook. 6th Edition. New York: McGraw-Hill, Inc., 1992. 17 Chen, W. F., Liew, Richard L. Y. The Civil Engineering Handbook. New York: CRC Press, 2003. 2nd Edition.

144HP soil

b⋅

=ρ

C-5PolyPipe 12/05

5

3

s R2144Lz3P

π⋅=

C-6PolyPipe 12/05

(22)

Where x = Horizontal distance from surface load, feet (Refer to Figure C-4) y = Horizontal distance from surface load, feet (Refer to Figure C-4) z = Vertical distance from top of pipe to surface load level, feet (Refer to Figure C-4)

Figure C-4

RESULTANT SURFACE LOAD

LIVE LOAD Live loading can be determined by extracting the load from Figure C-5 for H20 highway loading or from Figure C-6 for Cooper E-80 loading or by estimating, using available analytical techniques.

Figure C-5

H20 HIGHWAY LOADING Note: The H20 live load assumes two 16,000 lb. loads applied to two 18" x 20" areas, one located over the point in question, and the other located at a distance of 72" away. In this manner, a truckload of 20 tons is simulated. Source: American Iron and Steel Institute, Washington, DC

222 zyxR ++=

C-7PolyPipe 12/05

Figure C-6 COOPER E-80

Note: The Cooper E-80 live load assumes 80,000 pounds applied to three 2' x 6' areas on 5' centers, such as might be encountered through live loading from a locomotive with three 80,000 pounds axle loads.

Source: American Iron and Steel Institute, Washington, DC

TOTAL EXTERNAL LOADING

Total Load = Live Load + Backfill Load + Surface Load

(23)

Once the external loading on buried PolyPipe® has been determined, it will be necessary to calculate the critical buckling stress for contained PolyPipe® to determine if the pipe can withstand the external loading. The external loading capacity, or critical buckling stress, can be determined by the use of the following Von Mises formula:

(24)

Where cbP = Critical buckling stress, psi SF = Safety factor, PolyPipe® recommends SF=2 Rw = Water buoyancy factor, (dimensionless) B = Empirical Coefficient of Elastic Support, (dimensionless) Es = Soil modulus, (See Table C-4) E = Pipe modulus of elasticity, psi DR = Dimension Ratio

Where,

(25)

Hw = Height of water table above pipe, feet H = Height of soil cover above pipe, feet Note: Hw must be less than H and,

sblt PPPP ++=

2/1

3

67.21⎟⎠⎞

⎜⎝⎛ ⋅⋅⋅⋅

⋅=DR

EEBRSF

P swcb

⎟⎠⎞

⎜⎝⎛ ⋅−=

HHR w

w 33.01

(26)

Where e = 2.718 H = Height of soil cover above pipe, feet If the total external loading, Equation (23), is less than the critical buckling stress (Pt < Pcb), then the application should be considered safe. However, if this is not the case (Pt > Pcb), then the required parameters can be determined for a safe application from the following variations of the above equation:

(27)

or

(28)


HeB ⋅−⋅+

= 065.0411

⎟⎟⎠

⎞⎜⎜⎝

⎛

⋅⋅⋅⋅⋅

= 22

67.2

cb

sw

PSFEEBRDR

EBRDRSFPE

w

cbs ⋅⋅⋅

⋅⋅=

67.2

322

C-8PolyPipe 12/05

EFFECTS OF TEMPERATURE

THERMAL CONDUCTIVITY

The thermal conductivity of a material is expressed as the rate at which heat is transferred by conduction through a unit cross-sectional area of a material when a temperature gradient exists perpendicular to the area. The units generally used for expressing this value are BTU - in per hour, per square foot, per °F. PolyPipe®, like many thermoplastic materials, has a low coefficient of thermal conductivity. PolyPipe® has an "R" value of 0.3 BTU/in. Table D-1 below shows the value of PolyPipe® compared to the value of some conventional materials.

Table D-1 THERMAL CONDUCTIVITY OF MATERIALS

Material

BTU - in/ft2/hr/°F

Copper 3027 Aluminum 1457

Steel 411 Cast Iron 302

Glass 7.2 PolyPipe® 2.7 Urethane 0.6

Due to its low value of thermal conductivity, PolyPipe® is a fairly good insulator.

THERMAL EXPANSION AND CONTRACTION

As with all materials, PolyPipe® is subject to expansion/contraction due to changes in temperatures. It is important to consider this property when designing a piping system. The coefficient of thermal expansion/contraction, α, for PolyPipe® is approximately:

1.0 x 10-4 inch per inch per oF (1.75 • 10-4 mm/mm/°C)

The amount of expansion/contraction can be calculated by the following formula11:

(29)

Where Δl = Change in length, inches α = Coefficient of thermal expansion, 1.0 x 10-4 in/in/°F l = Initial pipe length, inches T1 = Initial temperature, °F T2 = Final temperature, °F

*NOTE: The calculated expansions in a line do not often occur unless the pipe is free of all frictional drag. EXAMPLE: A 500 ft. long (152 m) unrestrained pipe run is subjected to a temperature fluctuation from 90oF (32oC) during the day to 65oF (18oC) at night. Calculate the change in length due to the temperature difference from day to night.

( )( )( )( )125006590100.1 4 −=Δ −xl = 15 inches (1.25 feet)

11 Plastics Pipe Institute Technical Report-21. Thermal Expansion and Contraction in Plastics Piping Systems, 2001.

( )12 TTll −⋅⋅=Δ α

D-1PolyPipe 12/05

Temperature gradients produced through a change in fluid or ambient temperature will create a gradient across the pipe wall. The midwall temperature of the pipe will reflect neither the internal nor the external condition. The effect of the temperature gradient occurs more gradually due to the low thermal conductivity of PolyPipe®. Polyethylene, which is viscoelastic, undergoes a molecular rearrangement due to the temperature gradient. This restructure dissipates a large portion of the temperature-induced stresses. This behavior is referred to as stress relaxation and is considered beneficial to a pipe system that may experience temperature fluctuations. In certain circumstances, it is necessary to be able to calculate the degree of stress imparted to the pipe due to an environmental or process change. In a system where the pipe is restrained at both ends, a compressive stress is created. Thermally induced forces for polyethylene can be calculated from the following equation11:

(30) and,

(31)

Where F = Force, lbs σ = Stress, psi A = Pipe wall cross-sectional area, in2 E = Modulus of elasticity, psi Δ T = Temperature change, °F α = Coefficient of thermal expansion, 1.0 x 10-4 in/in/°F The modulus of elasticity, E, for polyethylene is a function of time and temperature. Please refer to the Plastics Pipe Institute (PPI) Engineering Handbook chapter on Engineering Properties for more information.

A buried system, by virtue of the continuous contact of the backfill material and the reduction in temperature fluctuations, needs no further special considerations. Pipe to soil friction will restrain the buried pipe in place. Above ground pipeline, however, does not have restraints and the thermal expansion/contraction must be allowed for in the design. The design must incorporate necessary restraints to accommodate adverse effects due to thermal expansion/contraction. This may be accomplished by one of the following methods: 1. The pipeline design contains no restraints allowing the pipeline to move freely. 2. Anchored closely and tightly so that unit changes occur in the elasticity of the material rather than transferring

all the forces to one point. 3. Anchoring ends and changes in direction with addition of expansion loops at or near the mid-point of a run. For long continuous pipelines laid above ground, the amount of expansion/contraction can be significant as a result of normal variances in temperature from day to night. The pipeline should be installed to minimize direct sunlight. As the pipe temperature increases, the movement is generally from side to side. Although this expansion cannot be prevented, placing anchor points at intervals along the line can control it. The formula(1) shown below is used to estimate the distance between the anchor points.


AF ⋅= σ

TE Δ⋅⋅= ασ

D-2PolyPipe 12/05

(32)

Where L = Distance between anchor points, inches Δ y = Lateral deflection, inches α = Coefficient of thermal expansion, 1.0 x 10-4 in/in/°F Δ T = Temperature change, °F Recommendations regarding the installation of the pipe expected to undergo temperature fluctuations are given in Section F.


TyL

Δ⋅Δ⋅

=α

22

D-3PolyPipe 12/05

CHEMICAL RESISTANCE15 Thermoplastic materials generally are resistant to attack from many chemicals, which make them suitable for use in many process applications. The suitability for use in a particular process piping application is a function of:

1. Material

A. The specific plastic material: ABS, CPVC, PP, PVC, PE, PB, PVDF, PEX, PA11, PK. B. The specific plastic material and its physical properties as identified by its cell classification according to

the appropriate ASTM material specification.

2. Product and Joint System

A. Piping product dimensions, construction, and composition (layers, fillers, etc.). B. Joining system. Heat fusion and solvent cementing do not introduce different materials into the system.

Mechanical joints can introduce gaskets such as elastomers, or other thermoplastic or non-thermoplastic materials used as mechanical fitting components.

C. Other components and appurtenances in the piping system.

3. Use Conditions - Internal and External

A. Chemical or mixtures of chemicals, and their concentrations. B. Operating temperature — maximum, minimum, and cyclical variations.

C. Operating pressure or applied stress — maximum, minimum and cyclical variations.

D. Life-cycle information — such as material cost, installation cost, desired service life, maintenance, repair

and replacement costs, etc.

Polyethylene does not rust, rot, pit or corrode as a result of chemical, electrolytic or galvanic action. Chemicals that pose potentially serious problems for polyethylene are strong oxidizing agents or certain hydrocarbons. These chemicals may reduce the pressure rating for the pipe or be unsuitable for transport. Either can be a function of service temperature or chemical concentration. Continuous exposure to hydrocarbons can lead to permeation through the material or elastomeric gaskets used at joints. The degree of permeation is a function of pressure, temperature, the nature of the hydrocarbons and the polymer structure of the piping material. The chemical environment may also be of concern where the purity of the fluid within the pipe must be maintained. Hydrocarbon permeation may affect pressure ratings and hinder future connections. For more detailed information on chemical resistance, The Plastics Pipe Institute (PPI) has prepared a technical report, TR-19 “Thermoplastic Piping for the Transport of Chemicals”, as a service to the industry. This document is available via download from the PPI website www.plasticpipe.org.


15 Plastics Pipe Institute Technical Report-19. Thermoplastic Piping for the Transport of Chemicals. 2000. E-1

PolyPipe 12/05

UNDERGROUND INSTALLATIONS

The installation of pipes constructed from conventional materials generally requires the joining and laying of the pipe piece by piece in the trench. This will necessitate the trench being of such width it will accommodate one or two installers carrying out the installation with their tools and enough room for them to work. Due to the flexibility and resilience of PolyPipe®, it can be pre-assembled above ground. This not only allows for ample working area, but also provides an opportunity for a thorough inspection of butt-fused joints prior to burial. The trench dimensions are very narrow in comparison to widths used for traditional materials and can be constructed by any one of a number of types of machinery. As with any operation, a large contribution to the success of the job can be made by adequate planning. In many instances it may not be possible to avoid some difficult circumstances that may result in extended installation time. This is particularly true for installation of steel pipe. As an example, in very uneven or hilly terrain, the lightweight of PolyPipe® would be a definite advantage allowing the pipe to be assembled in a more suitable area and then carried or pulled to the job site in longer sections for installation into the trench.

TRENCHING

As has been previously stated, the trench width should be as narrow as possible. The maximum width should be no more than the diameter of the pipe plus two feet. If possible, the trench can be made as narrow as the pipe itself plus one foot. The importance of the trench width is not so much the cost of the trenching, which is of course is a factor, but more the working efficiency of the finished system. Trenches should be as straight-sided as is practical and flat-bottomed to facilitate the proper consolidation and packing of the filling materials (See Figure F-2). In ground that is coarse grain with many large rocks or protrusions, it may be necessary to over-cut and lay a bed of fine gravel in the base of the trench to allow for stress-free bedding of the pipe. It is not recommended that ordinary sand be used for this purpose, as it is possible to be washed away, leaving the pipe unsupported. The formation of the base of the trench is of great importance. It should be as flat and level as possible or graded to the correct slope where specified. An installation where this is significant would be a gravity flow system. Grading can be accomplished by the use of gravel or finely crushed stone. If the condition of the soil is poor due to standing water in a high water table area, it may be required to establish more stabilization to the base of the trench after having drained the area first. In rocky terrain, the installation should be made such that the pipe is not laid in direct contact with the hard surface. The trench should be cut to a depth of six inches to one foot below the required level and then brought back to grade with soil or fine gravel. Ditches in soil that is loose may require a slope to the top edges of the trench to prevent the collapsing of the sides and filling of the trench (See Figure F-1(b)). In some cases it may be preferable to excavate a trench having a wider top section cut straight down to the intended top position of the pipe. This trench configuration is represented in Figure F-1(c). In either case, the backfilling of the trench will not result in higher earth load on the pipe.

Figure F-1 DITCH CONFIGURATIONS

(a) (b) (c)

F-1PolyPipe 12/05

PIPE CURVATURE

In the building of long runs of pipe it is often necessary to negotiate bends. The natural flexibility of polyethylene will allow runs of pipe to be pulled around fairly tight radii. Trenches can therefore be excavated to accommodate bends, which are within the capabilities of the pipe. The degree to which a pipe can be cold bent around a radius is dependent upon the diameter to wall thickness ratio, D/t, or the DR ratio. The table below lists minimum recommended bending radius for any size of pipe.

Table F-1 MINIMUM BENDING RADIUS

DR Ratio Minimum Radius Factor, Kmrf

32.5 40 26 36 21 32 17 26

15.5 24 11 or lower 20

By multiplying the minimum radius factor, Kmrf, by the actual outside diameter, D, of the pipe being installed you can determine the minimum bending radius, rm, for the pipe being installed. Use the following formula:

(33)

Example: 8” IPS SDR 32.5 pipe would have a minimum bending radius of (8.625”)(40) = 345” or 28.74’ A system that requires a bend and can be done so by utilizing the natural curvature of the pipe does not require the use of thrust blocks. However, tight bends in polyethylene should be buried or constrained. Where there is a need for the placement of a compression fitting, it may also be necessary to use an anchor or a thrust block. Fused or flanged joints generally do not require thrust blocking. Thrust blocks should be constructed of a poured reinforced concrete pad that partially encapsulates the fitting and prevents any relative movement between the straight section or "run" of the fitting and the branch. Thrust blocks must be poured on undisturbed soil or the soil must be compacted. In most cases, well compacted soil placed strategically against the heel of an elbow or the back of a tee is sufficient for thrust blocking. This precaution should be taken to prevent any unnecessary stressing of the pipe and to ensure that the expansion and contraction of the pipe is forced to take place in the direction it is designed to go.

PIPE LAYING

If the pipe is to be joined piece by piece at the trench site prior to being lowered into the trench, the transport of the pipe lengths to the work site is of little consideration. In those situations where on-site conditions require that several lengths be butt fused in a remote position from the trench, then there are some other considerations to be taken into account. The effect of pulling a number of joined lengths of pipe across the ground by gripping one end results in the generation of a tensile load in the pipe.

The size of pipe will determine the means used to lay the pipe in the trench. For sizes up to 6” (152mm) the pipe can be manhandled fairly readily and laid in the desired position. Single joints of up to 10” (254mm) in diameter can also be laid in the trench manually if they are to be butt fused afterwards. Sizes above 10” (254mm) will require moving and positioning with the use of equipment such as pry bars or perhaps light construction equipment. Larger diameters will need to be placed into the trench with rubber-tired lifting equipment or lifted into position with a cherry picker. In the pipe-laying phase, some accommodations can be made to allow for thermal expansion/contraction. Placement of the pipe in the trench will normally provide for some “snaking”. Even straight lengths have a tendency to wave from side to side. Pipe should not be pulled to straighten. Leave the side-to-side path and cut to length for the tie-in. Whenever possible, a final tie-in should be performed after an overnight stay in the trench to allow the pipe to cool down to near normal soil conditions.

mrfm KDr ⋅=

F-2PolyPipe 12/05

F-3

PolyPipe 12/05

Connections made to valves, rigid pipes or manholes should be supported. An alternative for some of these situations is the construction of a solidified, well tamped bedding below the joint. A concrete pad should be installed under the heavy member to resist settlement and preclude the polyethylene pipe supporting the component. The need for support of this kind is especially critical in unstable soil conditions.

PULLING LENGTHS The following information may be used to estimate an allowable pulling length for nominal polyethylene pipe applications. The equations shown below result in a pulling length that is based on short-term tensile strength. Use of pull forces greater than calculated may result in pipe damage. PolyPipe® recommends a load cell be used to monitor the applied force. This information is also available in PolyPipe® Info Brief #6. The Maximum Pulling Force (MPF) in pounds that may be applied to the pipe can be calculated by the following equation14:

(34)

Where MPF = Maximum pulling force, lbs (ATL and MPF are synonymous) fy = Tensile yield design (safety) factor, 0.40 ft = Time under tension design (safety) factor, 0.95* *The value of 0.95 is adequate for pulls up to 12 hours. T = Tensile yield strength, psi (See Table F-2 below) D = Outside diameter of pipe, inches DR = Dimension ratio (dimensionless)

Table F-2 TENSILE YIELD STRENGTHS

Tensile Yield Strength, psi

Temperature, oF PE3408 PE2406

73 3,500 psi 3,000 psi 100 2,800 psi 2,400 psi 120 2,300 psi 2,000 psi 140 1,800 psi 1,600 psi

Once the Maximum Pulling Force is determined, one can calculate the maximum pulling length, MPL, of the HDPE material for the type of installation. Installations can be divided into four categories:

1. On level soil. 2. Through an existing conduit that is empty. 3. Through an existing conduit where the HDPE and the existing conduit are both full of water. 4. Through a bored hole using the horizontal drilling technique.

1. LEVEL SOIL12: (35)

Where MPL = Maximum pulling length, feet MPF = Maximum pulling force, lbs (Equation (34)) f = Coefficient of friction on smooth sandy soil, 0.7 (dimensionless) W = Weight of pipe, lbs/ft 14 ASTM F1804-03. Standard Practice for Determining Allowable Tensile Load for Polyethylene (PE) Gas Pipe During Pull-In Installation. Volume 8.04. American Society of Testing and Materials. Baltimore, 2004. 12 Plastics Pipe Institute. Pipeline Rehabilitation by Sliplining with Polyethylene Pipe, 1993.

WfMPFMPL

⋅=

⎟⎠⎞

⎜⎝⎛ −⋅⋅⋅⋅⋅= 2

2 11DRDR

DTffMPF ty π

2. SLIPLINING EMPTY: For determining the Maximum Pulling Length of HDPE pipe through an existing conduit that is straight, level, and empty, PolyPipe® recommends using the same procedure for determining the pulling length on a relatively flat surface aboveground.

3. SLIPLINING WET: For slip lining conduits where the HDPE pipe and existing conduit are both full of water, the maximum allowable pulling length can be estimated by using a coefficient of friction of 0.1. 4. BORED HOLES: Estimating the maximum pulling length for holes as provided by the horizontal directional drilling (HDD) technique is more complex. Two references are available to assist in the design of HDD applications: Plastics Pipe Institute (PPI) Engineering Handbook, “Polyethylene Pipe for Horizontal Directional Drilling” available at their website, www.plasticpipe.org; and, ASTM F1962, “Standard Guide for Use of Maxi-Horizontal Directional Drilling for Placement of Polyethylene Pipe or Conduit Under Obstacles, Including River Crossings”. If further assistance is needed, please contact PolyPipe® Technical Services Department at (800) 433-5632. Before the pipe is pulled into position, a survey of the area should be made to ensure that surface conditions will not cause the pipe to suffer any damage in the form of gouges or deep scarring. A system of rollers constructed from short lengths of pipe can be used to reduce the pulling force required and to keep the pipe off the ground. A pulling head is used to attach to the leading end of the pipe. This can take the form of a simple rubber pad with steel cable wrapped around the pipe or can be more sophisticated in the form of a pulling head. The pipe should never be pulled by attaching to the flange. If flange assemblies are installed, these must be elevated to avoid dragging, both in front and behind.

BACKFILLING

Not only is backfill utilized to fill the trench, but it also serves a very specific design function. The main purpose of the backfill material is to provide adequate support and protection for the pipe. By ensuring the backfill is solid and continuous, damage can be prevented from surface traffic, falling rock or lifting due to the trench filling with water. The soil used for backfill can be the original soil excavated from the trench or foreign soil that has been transported to the site. Whatever soil is used, it is recommended that the haunching and the initial backfill material be free of any rocks, hard lumps, frozen material or clay. It should also be sufficiently friable to readily flow into the haunches of the pipe. It is important that the initial backfill be consolidated to ensure continuous contact and support of the pipe (See Figure F-2). This can be achieved by using fill material that is of fine sand or clay based materials. These materials should only be used in dry areas where it is unlikely to be washed out.

Figure F-2 PROPER BACKFILL

Improper Backfill Proper Backfill

F-4PolyPipe 12/05

http://www.plasticpipe.org/

TRENCH CONFIGURATION AND TERMINOLOGY

The figure below describes a typical, well-constructed trench arrangement and gives the correct descriptive terminology for the various components.

Figure F-3 TRENCH CONFIGURATION

Foundation and Bedding - Use of foundation material may only be required where the base of the trench is required to be brought up to the pipeline level, or when encountering an unstable or rocky trench bottom. As noted earlier, this can be soil or fine gravel. Haunching - The haunching provides stability to the pipe from the sides and from underneath. The best material is crushed stone, fine gravel or coarse sand, and should be tampered into position with a narrow tamping tool to ensure that the material is well consolidated under the sides of the pipe as well as around it. The haunching material must be poured into the trench gradually so that the tamping operation can be carried out simultaneously with the placement. Applying too much of the material at one time may cause a bridging effect which will result in a cavity being formed below the pipe, which can later result in a loss of support for the pipe.

Figure F-4 PROPER HAUNCHING

Correct Haunching Incorrect Haunching Initial Backfill – Materials include coarse sand, fine gravel or crushed stone. This section of the backfilling should be carried out the same as with the haunching. The material should be gradually added in 4-6 inch (102-152 mm) lifts and tamped simultaneously. The initial backfill should be brought up to a height of 6-12 inches (152-305 mm) above the top of the pipe, depending upon the size of the pipe.

F-5PolyPipe 12/05

Final Backfill - As previously mentioned, the final backfill can be the original excavated material or other convenient soil, provided it does not contain excessively large rocks or frozen lumps that may damage the pipe initially or later allow washing away and the loss of consolidation. The backfill should be compacted per the requirements addressed in Chapter E. In areas where a high water table exists, it is necessary to allow for the effect of buoyancy of the pipe and of the backfill material. The result of the fill material being saturated due to the water table will reduce the load imparted on the pipe. In these conditions, the conventional trench configuration will no longer be sufficient to overcome a tendency for the pipe to float. This situation can be addressed by designing for a certain amount of extra cover to ensure the pipe will remain in place. The required depth of cover can be calculated from the equation below:

(36)

Where H = Minimum backfill depth, feet ρw = Density of water, lbs/ft3 Wp = Weight of pipe, lbs/ft ρs = Density of soil, lbs/ft3 D = Outside diameter, inches d = Inside diameter, inches

RECOMMENDED TESTING PROCEDURE

LEAK TESTING

The intent of leak testing is to find unacceptable faults in a piping system. If such faults exist, they may manifest themselves by leakage or rupture. Leakage tests may be performed if required in the Contract Specifications. Testing may be conducted in various ways. Internal pressure testing involves filling the test section with a nonflammable liquid or gas, then pressurizing the medium. Hydrostatic pressure testing with water is the preferred and recommended method. Other test procedures may involve paired internal or end plugs to pressure test individual joints or sections, or an initial service test. Joints may be exposed to allow inspection for leakage. Liquids such as water are preferred as the test medium because less energy is released if the test section fails catastrophically. During a pressure test, energy (internal pressure) is applied to stress the test section. If the test medium is a compressible gas, then the gas is compressed and absorbs energy while applying stress to the pipeline. If a catastrophic failure occurs, both the pipeline stress energy and the gas compression energy are suddenly released. However, with an incompressible liquid such as water as the test medium, the energy release is only the energy required to stress the pipeline. WARNING: Pipe system pressure testing is performed to discover unacceptable faults in a piping system. Pressure testing may cause such faults to fail by leaking or rupturing. This may result in catastrophic failure. Piping system rupture may result in sudden, forcible, uncontrolled movement of system piping or components, or parts of components. WARNING: Pipe Restraint. The pipe system under test and any closures in the test section should be restrained against sudden uncontrolled movement from catastrophic failure. Test equipment should be examined before pressure is applied to insure that it is tightly connected. All low pressure filling lines and other items not subject to the test pressure should be disconnected or isolated. WARNING: Personal Protection. Take suitable precautions to eliminate hazards to personnel near lines being tested. Keep personnel a safe distance away from the test section during testing.

( )D

WdDH

s

pw

⋅⋅

−−⋅⋅=

ρπρ

48

22

F-6PolyPipe 12/05

Pressure Testing Precautions

The piping section under test and any closures in the test section should be restrained or otherwise restricted against sudden uncontrolled movement in the event of rupture. Expansion joints and expansion compensators should be temporarily restrained, isolated or removed during the pressure test. Testing may be conducted on the system, or in sections. The limiting test section size is determined by test equipment capability. If the pressurizing equipment is too small, it may not be possible to complete the test within allowable testing time limits. If so, higher capacity test equipment, or a smaller test section may be necessary. If possible, test medium and test section temperatures should be less than 100oF (38oC). At temperatures above 100oF (38oC), reduced test pressure is required. Before applying test pressure, time may be required for the test medium and the test section to temperature equalize. Contact the pipe manufacturer for technical assistance with elevated temperature pressure testing.

Test Pressure

Valves, or other devices may limit test pressure, or lower pressure rated components. Such components may not be able to withstand the required test pressure, and should be either removed from, or isolated from the section being tested to avoid possible damage to, or failure of these devices. Isolated equipment should be vented. For continuous pressure systems where test pressure limiting components or devices have been isolated, or

removed, or are not present in the test section, the maximum allowable test pressure is 1.5 times the system design pressure at the lowest elevation in the section under test.

If the test pressure limiting device or component cannot be removed or isolated, then the limiting section or system test pressure is the maximum allowable test pressure for that device or component.

For non-pressure, low pressure, or gravity flow systems, consult the piping manufacturer for the maximum allowable test pressure.

Test Duration

For any test pressure from 1.0 to 1.5 times the system design pressure, the total test time including initial pressurization, initial expansion, and time at test pressure, must not exceed eight (8) hours. If the pressure test is not completed due to leakage, equipment failure, etc., the test section should be de-pressurized, and allowed to "relax" for at least eight (8) hours before bringing the test section up to test pressure again.

Pre-Test Inspection

Test equipment and the pipeline should be examined before pressure is applied to ensure that connections are tight, necessary restraints are in-place and secure, and components that should be isolated or disconnected are isolated or disconnected. All low pressure filling lines and other items not subject to the test pressure should be disconnected or isolated.

Hydrostatic testing

Hydrostatic pressure testing is preferred and is strongly recommended. The preferred testing medium is clean water. The test section should be completely filled with the test medium, taking care to bleed off any trapped air. Venting at high points may be required to purge air pockets while the test section is filling. Venting may be provided by loosening flanges, or by using equipment vents. Re-tighten any loosened flanges before applying test pressure.

Monitored Make-up Water Test

The test procedure consists of initial expansion, and test phases. During the initial expansion phase, the test section is pressurized to the test pressure, and sufficient make-up water is added each hour for three (3) hours to return to test pressure. After the initial expansion phase, about four (4) hours after pressurization, the test phase begins. The test phase may be one (1), two (2), or three (3) hours, after which a measured amount of make-up water is added to return to test pressure. If the amount of make-up water added does not exceed Table F-3 values, leakage is not indicated.

F-7PolyPipe 12/05

Table F-3 TEST PHASE MAKE-UP AMOUNT

Nominal Pipe Size U.S. Gals/100 ft of Pipe Nominal Pipe Size U.S. Gals/100 ft of Pipe

inches 1-Hour 2-Hour 3-Hour inches 1-Hour 2-Hour 3-Hour 2 0.07 0.11 0.19 20 2.80 5.50 8.00 3 0.10 0.15 0.25 22 3.50 7.00 10.50 4 0.13 0.25 0.40 24 4.50 8.90 13.30 5 0.19 0.38 0.58 28 5.50 11.10 16.80 6 0.30 0.60 0.90 30 6.30 12.70 19.20 8 0.50 1.00 1.50 32 7.00 14.30 21.50

10 0.80 1.30 2.10 36 9.00 18.00 27.00 12 1.10 2.30 3.40 42 12.00 23.10 35.30 14 1.40 2.80 4.20 48 15.00 27.00 43.00 16 1.70 3.30 5.00 54 18.50 31.40 51.70 18 2.00 4.30 6.50 -- -- -- --

Non-monitored Make-Up Water Test The test procedure consists of initial expansion, and test phases. For the initial expansion phase, make-up water is added as required to maintain the test pressure for four (4) hours. For the test phase, the test pressure is reduced by 10 psi. If the pressure remains steady (within 5% of the target value) for an hour, no leakage is indicated. The above testing procedures were taken from the Plastic Pipe Institute Engineering Handbook; Inspections, Tests and Safety Concerns.

Pneumatic Testing for Gravity Sewers

For gravity sewer lines, low-pressure air may be used as per ASTM F1417. However, any other pneumatic testing is not recommended. Additional safety precautions may be required. The piping manufacturer should be consulted before using pressure-testing procedures other than those presented here. Other pressure testing procedures may or may not be applicable depending upon piping products and/or piping applications.

NOTICE: The data contained herein is a guide to the use of PolyPipe® polyethylene pipe and fittings and is believed to be accurate and reliable. However, general data does not adequately cover specific applications, and its suitability in particular applications should be independently verified. In all cases, the user should assume that additional safety measures may be required in the safe installation or operation of the project. Due to the wide variation in service conditions, quality of installation, etc., no warranty or guarantee, expressed or implied, is given in conjunction with the use of this material.

F-8

PolyPipe 12/05

MARINE APPLICATIONS

PolyPipe® is ideally suited for use in marine application, whether it be oceans, lakes, ponds, swamps, or rivers. The crossing of a fluidized area with a polyethylene pipeline has some similarities and some differences to normal on-shore installations. Recognizing and treating these design and operating parameters is important. Polyethylene pipe, due to its cross-sectional density, will float near or on the liquid surface. Transporting a liquid comparable to the external liquid allows the polyethylene to float with the crown of the pipe just breaking the surface. The inherent qualities of PolyPipe® (flexibility, light weight, corrosion resistance, homogeneous lengths and abrasion resistance) allow its’ acceptance in dredging, aeration ponds, outfall and intake lines. Factors to be considered in the installation of marine pipelines include the following:

Flotation or sinking Internal pressure capabilities Collapse resistance of pipe Weighting

FLOTATION OR SINKING

A polyethylene pipeline with comparable densities of liquid inside and outside will float in equilibrium at the surface. An increase in weight of 10-20% of pipe weight will sink the pipe to the bottom, provided no underwater currents exist. A line from a dredge or across a settling pond will float while pumping only water. If solids are introduced or the density of the fluid is higher than the surrounding fluid, the pipeline will sink. This operational technique may be acceptable in this instance and require neither anchors nor flotation devices. If the pipeline is to be moved, the line should be flushed until flotation occurs. Where flotation of the line is desired or to maintain the profile at or near the surface, various forms of collars, saddles, and strap-on devices are available. These can be continuous supports or placed at intervals approximately double that required for weights. Parallel-capped polyethylene pipelines can also be utilized as flotation devices. Size and spacing of flotation collars is based on desired position of the carrier pipe relative to the water surface and weight of the pipeline. For underwater installations, it is important to select the proper weight and spacing of the weight. Whenever possible, an underwater pipeline should be installed in a trench.

INTERNAL PRESSURE

A marine pipeline, like any other, should be designed to withstand the anticipated pressure and pressure surges. In some cases, other design parameters require a heavier wall than does the working pressure. In these cases, offshore design should prevail on the marine portion and conventional design should prevail for the on-shore portion.

COLLAPSE RESISTANCE

The piping application and installation procedure can require a heavier wall pipe than pressure carrying capabilities alone. Resistance to collapse of the pipe due to bending, external loading or environmental forces must be addressed. See Table A-7 for external load capabilities of PolyPipe® and Section C for method of calculating collapse pressures. The pipe, being submerged, is subjected to external pressures from the surrounding fluid. This pressure may have the effect of causing a collapse if the pipe should be only partially full, or, in the worst case, totally empty. If the pipe is full and open-ended, the pressure on the inside will normally equal or exceed the pressure on the outside, depending upon the pumping, and a collapse situation is not a consideration.

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INSTALLATION

Except in rare instances, where very long lengths of polyethylene pipe are required, the pipe can be joined by thermal fusion and have the proper sized weights installed on-shore. These individual lengths may then be towed into place, joined by flanged joints or by thermal fusion, and sunk in a predetermined course. Once a pipeline has been installed in a body of water, changes in liquid flow around the pipe create different paths. A pipeline installed on the bottom will have flows that may wash material from beneath the pipeline, creating more upward lift than lying on the bottom. This will build sediment banks on the upstream side and eddy pools on the downstream side that the weighted pipe may settle into. It is worthy of note that currents as high as eight feet per second, or even higher in rivers and streams are possible. If these conditions apply to the installed pipeline, additional design considerations should be given for additional weight, spacing of weights and heavier wall pipe. Burial of marine pipelines, while not always possible, should not be considered as a solution where current velocities exceed two feet per second. Present burial techniques employ natural sedimentation processes. At some stage of the sediment accumulation, there is likely to be a period in which the sediment is sufficiently fluidized to exert significantly higher buoyant forces than water alone.

CONTROLLED SINKING OF POLYPIPE

A polyethylene pipeline, with weights attached, ends capped and filled with air at atmospheric pressure may be gradually sunk into position by allowing the entrance of water on a controlled basis. Filling should begin at a point of joining to a fixed structure and proceed away. It is important to maintain progressive filling so as to lessen the chance of an air pocket and a hump in the line filled with air. It is equally important to maintain a higher elevation with the air-bleeding end of the pipeline so as to preclude water entering and filling from each end. When an air pocket is captured in the middle of a line, introducing a squeegee at the fixed end and forcing it outward with water under pressure can displace it.

WEIGHTING

PolyPipe® may be weighted and held in place by several methods. Concrete weights are the most common. These may be either strap-on or set-on type weights. It is also possible to use screw anchors with saddles to hold the pipe down. In some instances it may be best to install underwater pilings with crossbars to strap the pipe and hold it in suspension between the surface and the bottom. A pipeline used for transporting a gaseous medium or one that may have periods of gaseous pockets will have to be weighted heavily to maintain its position on the bottom. Pipelines transporting liquids can be weighted significantly lighter. Open-ended pipelines, such as outfall or intake pipelines, that have little chance of trapping air in pockets to float the line, may be weighted only 10-15% over equilibrium, provided no environmental forces are exerted on the line. All forms of weighting devices used in restraining polyethylene pipelines should be padded from the pipe with a resilient, impermeable padding to protect the pipe from sharp projections of concrete or metal clamps. Neoprene sheeting or other similar compressible material from 1/8” (up to 12” nominal pipe) to 1/4” (>12” nominal pipe) in thickness is recommended. Under set-on weights, the padding should be strapped to the pipe with stainless steel banding. Concrete weights should be poured from 140-160 lbs per cubic foot concrete. Both strap-on and set-on weights should be reinforced with steel rebar. Concrete weights for 4 inch and smaller pipe may be reinforced with wire mesh. Bolts, nuts, and other hardware used on underwater pipelines should be of corrosion resistance material suitable to the particular location.

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Anchor Weight Design The weight required to sink a pipeline is a function of the liquid volume displaced by the body (pipe), the weight of the submerged bodies including the pipe, pipe contents, weights and the environmental conditions. To determine the weight of the anchor in the surrounding fluid (or submerged weight), use the following formula: Wt. of fluid in pipe

(37)

Buoyancy of pipe Where Ws = Weight of anchor in surrounding fluid, lbs/ft Wp = Weight of pipe, lbs/ft ρs = Density of surrounding fluid, lbs/ft3 (water, 62.4 lbs/ft3) ρf = Density of fluid inside pipe, lbs/ft3 (water, 62.4 lbs/ft3) OD = Outside diameter, inches d = Inside diameter, inches K = Anchor constant (Refer to Table G-1)

*Note: Reference Table A-2 thru Table A-4 for pipe weights and dimensions. The value of K, the anchor constant, should vary with the wave, tide or current conditions that are known or that are anticipated in the pipeline crossing area. K should have a value greater than 1.0, unless neutral buoyancy is desired.

Table G-1

ANCHOR CONSTANT VALUES

K, Anchor Constant Environmental Condition

1.0 Neutral Buoyancy

1.3 Ponds, lakes, slow moving streams or rivers, low currents or tidal actions

1.5 Significant stream or rover currents or tidal flows

A positive (+) force (↓) indicates the pipeline will sink without additional weighting, provided no extraneous lifting forces are imposed on the pipeline. However, a (-) resultant force (↑) indicates additional weight is required to sink the pipeline. Once the proper material has been chosen for the anchor weight, the required weight can be determined from the following equation:

(38)

Where Wd = Weight of anchor on dry land, lbs S = Anchor weight spacing, ft ρa = Density of anchor weight material, lbs/ft3

The length between anchor weights, S, can vary with pipe size. A nominal 2-inch or smaller pipe should be weighted with a ribbon weight, weights or anchors at 6–8 foot intervals. Pipe sizes 3-12 inch should have weights every 8-12 feet and anything larger at 12-15 foot intervals.

( )sa

asd K

WSWρρ

ρ⋅−

⋅⋅=

( ) ( )[ ]KODdWW sfps ⋅⋅−⋅⋅

+= 22

4144ρρπ

G-3PolyPipe 12/05

A pipeline with weights attached on dry land should be handled carefully so as not to buckle the pipe. The can be accomplished by ramping the banks to the water’s edge and sliding the pipe on the ground after the weights have been installed. If installing from a lay barge in the water, the weighted pipe should be supported with a stringer from the barge. Design and Construction of Ballast Weights16 To prevent damage to ballasts when handling, tightening and moving PE pipe, they are typically made of suitably reinforced concrete. Ballasts can be made to different shapes, although a symmetrical design such as round, square or hexagonal is preferred to avoid twisting during submersion. Flat-bottomed ballasts are preferred if the submerged piping is likely to be subjected to significant currents, tides or wave forces because they help prevent torsional movement of the pipe.

Also, when such conditions are likely to occur the ballasts should place the pipeline at a distance of at least one-quarter of the pipe diameter above the sea or riverbed. The lifting force caused by rapid water movement that is at a right angle to a pipe that rests on, or is close to a sea or riverbed is significantly greater than that which acts on a pipe that is placed at a greater distance from the bed. This means that ballasts designed to give an open space between the pipe and the bed will give rise to smaller lifting forces. The ballasts should be comprised of a top and bottom section that when mated together with a minimum gap between the two halves provides for a resultant inside diameter that is slightly larger than the outside diameter of the pipe. This slightly larger inside diameter is to allow the placement of a cushioning interlining to protect the softer plastic pipe from being damaged by the hard ballast material. Another function of the interlining is to provide frictional resistance that will help prevent the ballasts from sliding along the pipe during the submersion process. Accordingly, slippery interlining material such as polyethylene film or sheeting should not be used. Some suggested interlining materials include several wraps of approximately 1/8-inch thick rubber sheet or approximately ¼-inch thick neoprene sponge sheet. Additionally, experience has shown that in certain marine applications where tidal or current activity may be significant, it is feasible for the pipe to “roll” or “twist”. This influence combined with the mass of the individual ballasts may lead to a substantial torsional influence on the pipe. For these types of installations, an asymmetric ballast design in which the bottom portion of the ballast is heavier than the upper portion of the ballast is recommended. For additional information on the design of this type of ballast, refer to Appendix A-3 of the PPI Engineering Handbook Chapter on Marine Applications. Suitable lifting lugs should be included in the top and bottom sections of the ballasts. The lugs and the tightening hardware should be corrosion resistant. Stainless steel strapping or corrosion resistant bolting is most commonly used. Bolting is preferable for pipes larger than 8-inch in diameter because it allows for post-tightening prior to submersion to offset any loosening of the gripping force that may result from stress-relaxation of the pipe material. Concrete ballast designs may take on a variety of different sizes, shapes and configurations depending on job-site needs, installation approach and/or availability of production materials. Table G-2 below provides some typical designs for concrete ballasts and details some suggested dimensional considerations based on pipe size, density of unreinforced concrete at 144 lbs/ft3 and percent air entrapment in a typical underwater installation. These dimensions are intended for reference purposes only after a careful analysis of the proposed underwater installation in accordance with the guidelines presented in the PPI Engineering Handbook Chapter on Marine Applications has been completed. 16 Plastics Pipe Institute. Marine Applications, 2004.

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Table G-2 SUGGESTED CONCRETE WEIGHT DIMENSIONS

Weight Spacing to Offset % of Air, feet

Approx. Weight of Concrete

Block, lbs.

Approximate Block Dimensions, inches Bolt

Dimensions, inches

Nominal Pipe Size, IPS

Actual OD,

inches 10% 15% 20% In Air In

Water D X Y T S, min W Dia. Length

3” 3.50 10 6 ¾ 5 12 7 4 9 3 ¾ 2 ½ 1 ½ 2 ½ ¾ 12 4” 4.50 10 6 ¾ 5 20 10 5 11 4 ¾ 2 ½ 1 ½ 3 ¾ 12 5” 5.56 10 6 ¾ 5 30 18 6 12 5 ¼ 3 ½ 1 ½ 3 ¾ 12 6” 6.63 10 6 ¾ 5 35 20 7 ⅛ 13 5 ¾ 3 ½ 1 ½ 3 ¾ 12 7” 7.13 10 6 ¾ 5 45 26 7 ⅝ 13 ½ 6 4 ¼ 1 ½ 3 ¾ 12 8” 8.63 10 6 ¾ 5 55 30 9 ¼ 15 ¼ 6 ⅞ 4 ¼ 1 ½ 3 ¾ 12

10” 10.75 10 6 ¾ 5 95 55 11 ¾ 19 ¼ 8 ⅝ 4 ½ 2 4 ¾ 12 12” 12.75 10 6 ¾ 5 125 75 13 ¼ 21 ¼ 9 ⅝ 5 2 4 ¾ 13 13” 13.38 10 6 ¾ 5 175 100 13 ⅞ 24 11 5 ¼ 2 5 ¾ 13 14” 14.00 15 10 7 ½ 225 130 14 ½ 24 ½ 11 ¼ 6 ½ 2 5 1 13 16” 16.00 15 10 7 ½ 250 145 16 ½ 26 ½ 12 ¼ 6 ½ 2 5 1 13 18” 18.00 15 10 7 ½ 360 210 18 ½ 28 ½ 13 ¼ 8 ¼ 2 5 1 13 20” 20.00 15 10 7 ½ 400 235 20 ½ 30 ½ 14 ¼ 8 ¼ 2 6 1 13 22” 22.00 15 10 7 ½ 535 310 22 ½ 34 ½ 16 ¼ 8 ½ 2 6 1 13 24” 24.00 15 13 ½ 7 ½ 610 360 24 ½ 36 ½ 17 ¼ 8 ¾ 2 6 1 13 28” 28.00 20 13 ½ 10 900 520 28 ½ 40 ¼ 19 ¼ 11 ¼ 2 6 1 13 36” 36.00 20 13 ½ 10 1430 830 36 ½ 48 ½ 23 ¼ 13 ½ 2 6 1 13 42” 42.00 20 13 ½ 10 1925 1125 42 ½ 54 ½ 26 ¼ 15 2 6 1 13

1. Suggested underpad material: 1/8” black or red rubber sheet, or ¼” neoprene sponge padding. Width should be “T” + 2” minimum to

prevent concrete from contacting pipe surface. 2. Concrete interior should be smooth (3000 psi – 28 days) 3. Steel pipe sleeves may be used around the anchor bolts (1” for ¾” bolt, etc.). Hot dip galvanize bolts, nuts, washers and sleeves. 4. A minimum gap, “S”, between mating blocks must be maintained to allow for tightening on the pipe. 5. To maintain their structural strength some weights are more than the required minimum. 6. Additional weight may be required for tide or current conditions. 7. Weights calculated for fresh water. 8. All concrete blocks should be suitably reinforced with reinforcing rod to prevent cracking during handling, tightening and movement of

weighted pipe.

Figure G-1 SCHEMATICS OF CONCRETE BALLAST DESIGNS

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Figure G-2 TYPICAL DETAIL OF CONCRETE BALLAST SHOWING

1” GAP BETWEEN BALLAST SECTIONS

For additional information on the design considerations for marine applications, refer to the Plastics Pipe Institute (PPI) Engineering Handbook chapter on Marine Applications. This document is available via download from the PPI website www.plasticpipe.org.


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http://www.plasticpipe.org/

SLURRY APPLICATIONS

Slurry is defined as a two-phase mixture of a solid in a fluid where the two constituents do not react chemically but can be mechanically separated. There are two basic types of slurry. The first being a non-settling slurry in which all particles remain entrained in the liquid. In this type of flow, the slurry resembles characteristics of a viscous fluid and can be treated as such in the design of the system. The second and more typical flow regime for slurries is the settling slurry. In this condition, the particles, once suspended in the liquid, begin to settle on the lower portion of the pipe. The degree of settling is dependent upon the velocity of the system. Larger particles are harder to suspend and require higher velocities to remain in suspension, especially in horizontal pipes. The critical velocity, Vc, is defined as the minimum velocity required for suspension of the solids constituting the slurry. The critical velocity is dependent on the following system variables:

Solid size and shape Solid size distribution Solid density Fluid density Slurry concentration Size of the pipe

FLOW REGIMES

In order to make use of the benefits of PolyPipe® in slurry applications, it is useful to understand the phenomenon of abrasion caused by the different types of slurry. There are four flow types that can exist in a slurry line, all of which are the result of variances in the flow rates. Therefore, changes in the velocity can bring about any of the flow conditions shown below:

1. Homogenous All of the particles are evenly distributed and entrained in the fluid resulting in minimal contact between the solid and the pipe wall. This condition is the least abrasive to the pipe material; therefore, the most desirable.

2. Heterogenous

In this case, there is some tendency to settle toward the bottom of the pipe resulting in increased density of the slurry in the bottom half of the pipe. However, the solids are still not in full contact with the pipe wall while in transit; therefore, minimal abrasion occurs. This condition is the most economical since achieving homogenous flow requires more energy.

3. Saltation

Solid particles tend to bounce on the bottom of the pipe causing abrasion in steel pipe, but in PolyPipe® solids rebound due to the characteristics of the piping material resulting in lower wear rates.

4. Sliding Bed

This is the most aggressive condition, where particles have fallen out of suspension and are being rolled and dragged along the bottom of the pipe. In this case, very high degrees of abrasion occur especially in the bottom quadrant of the pipe.

Increasing or decreasing the flow velocity can accomplish the transition between flow conditions described above. For example, a slurry application in the saltation flow can be improved to heterogenous flow by increasing the flow velocity. It should, however, be borne in mind that increasing the flow velocity is achieved at an increased cost. This should be taken into consideration when costing out the installation.

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PARTICLE SIZE For an application in which the particle size is very fine (such as fly-ash), the solid phase forms a viscous fluid with the liquid carrier and demonstrates homogenous flow. This condition exists so long as the fluid velocity is maintained above the critical velocity. When the velocity drops below the critical transition level, the solids begin to settle and the flow condition changes from turbulent flow to one of laminar flow. In the laminar flow condition, the slurry assumes the saltation or the sliding bed flow condition. Therefore, for this type of slurry, it is important to maintain the flow rate at a level above the critical transition velocity in order to avoid significantly higher wear rates.

Typical types of material for which this consideration is of importance are those with particle sizes below 200 microns. These can include the following material types:

Boiler fly ash Fine sands Clays Scrubber solids Pulverized coal Materials that have been reduced to powder

For slurries containing fine materials, as represented above, two-phase separation can be caused by the following changes in the system:

1. Increase in slurry viscosity 2. Increase in solids concentration 3. Decrease in particle size

In each of the above cases, an increase in the flow velocity can prevent settling from occurring. An application in which the particle size is not below 200 microns requires a different consideration. Larger, heavier particles behave differently in suspension than the finer slurries and will not form homogenous flow situations. For such materials, the best situation that can be achieved is the heterogenous flow condition. Due to the large size of the particle and its’ significant density, the inertia of the particle results in a falling of the solid content through the fluid, even at high velocities. This condition is true for full flow conditions, resulting in a higher concentration of the solids in the lower half of the pipe. Once the flow rate is below the critical velocity, the amount of solids begins to increase in the bottom of the pipe resulting in an increase in the degree of wear that can take place. In most cases, the critical velocity for larger particles is in the turbulent flow regime. Typical slurry materials that are in this category include the following:

Mine tailings Sand Mineral ores Crushed limestone Gravel Dredge materials

In the case of the slurry having larger, heavier particles the following changes can increase the tendency to "drop-out" of suspension:

1. Increase in particle size 2. Increase in solids density 3. Increase in solids concentration 4. Employment of a larger pipe diameter

An increase in flow velocity can prevent “fall-out” of particles and maintain a heterogenous flow.

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FLUID VELOCITIES Shown below, Table H-1, are suggested fluid velocities by particle size and pipe size to attain optimum service.

Table H-1

SUGGESTED FLUID VELOCITIES

Pipe Size

PARTICLE SIZE 3 - 10 in (76-254 mm)

10 - 28 in (254-711 mm)

28 - 48 in (711 - 1216 mm)

200 Micron to ¼ inch 7 - 10 ft/sec 8 - 12 ft/sec 10 - 15 ft/sec

(2.1 - 3.0 m/sec) (2.4 - 3.7 m/sec) (3.0 - 4.6 m/sec)

> ¼ inch 10 - 13 ft/sec 12 - 16 ft/sec 14 -18 ft/sec (3.0 - 4.0 m/sec) (3.7 - 4.9 m/sec) (4.3 - 5.5 m/sec)

For slurry applications, flow velocities below the critical level can result in very high wear rates possibly even plugging of the line.

PRESSURE LOSS The pressure loss of slurry in a piping system due to friction can be estimated by using the Hazen-Williams equation from Section B, “Pressure Drop”. The calculated pressure drop, ΔPf, multiplied by the specific gravity of the slurry will approximate the frictional pressure drop. This is represented by the following equation:

(39)

Where ΔPS = Pressure loss due to friction for slurry, psi/100 ft. ΔPf = Pressure loss due to friction, psi/100 ft., (Equation (6)) SG = Specific gravity of slurry, (dimensionless) NOTE: The value obtained by this calculation procedure can be no more accurate than the determination of the specific gravity but is recognized as yielding safe estimates. PolyPipe® high molecular weight polyethylene pipe has an extremely high resistance to abrasion caused by slurries. When compared to traditional materials, PolyPipe® has a higher resistance. For example, PolyPipe® can outlast steel by as much as 4 to 1 in a given situation. This factor is only one of the benefits of using PolyPipe® for slurry applications; it is also lighter in weight and easier to install in areas where slurry lines are required. Unfortunately, due to the significant number of variables involved with slurry applications, it is difficult to establish a reference for abrasion rates of polyethylene pipe. In addition, polyethylene pipe is easier to maintain and can be easily rotated once wear has taken place. PolyPipe® recommends periodic rotation of the slurry pipeline. The frequency of the rotation depends on the properties of the slurry mixture being transported through the pipeline.


SGPP fS ⋅Δ=Δ

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OVERHEAD OR INTERMITTENTLY SUPPORTED PIPELINES

Items of consideration in the installation of intermittently supported pipelines are: 1. Supported spacing 2. Type of support 3. Temperature influence 4. Pipeline weight and sag 5. Installation

SAG

The amount of sag in mid-span depends upon the weight of the pipe per foot, including effluent. Figure J-1 gives the recommended spacing for a mid-span deflection of one-quarter of an inch when full of water. However, in situations where a dry gas is being carried, the indicated span can be doubled. When condensation occurs in the pipeline, the liquid accumulates in the sag, unless the pipe is sloped; therefore, accelerating the sag due to the increased weight. If less deflection is desired, new support spacing can be determined by multiplying the spacing by the following correction factors: 1. 0.67 for 0.05 inch (1.3 mm) deflection 2. 0.80 for 0.10 inch (2.5 mm) deflection 3. 0.88 for 0.15 inch (3.8 mm) deflection 4. 0.95 for 0.20 inch (5.1 mm) deflection

Figure J-1 SUPPORT SPACING FOR INTERMITTENTLY SUPPORTED PIPELINES

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TEMPERATURE Figure J-1 provides for design of spacing to accommodate temperature differentials the pipeline may experience. An increase in temperature decreases the beam strength of the pipeline resulting in an increase in the amount of sag.

Note: A pipeline operating at temperatures above 150ºF (65ºC) should have continuous support. Figure J-1, however, does not take into consideration the additional sag that can take place due to thermal expansion because of temperature increases. For this reason, the pipe temperature at the time of installation becomes very important and final tie-ins should be made as near as possible to or above the operating temperature. If a 100 ft. (30.5m) pipeline is installed and tied-in at 60ºF (16ºC) and operated at 120ºF (49ºC), as much as a 7 inch (178 mm) increase in length may occur that will manifest itself as additional sag.

SUPPORT

Polyethylene is a relatively soft material and requires rather wide, padded surfaces for supports. A pipeline full of water is approximately three (3) times the weight of an empty line or a line conveying gaseous materials. Support for lines flowing full of water should be at least as wide in the longitudinal pipeline direction as one-half the pipe outside diameter. The support should cradle the pipe for approximately 135 degrees, i.e., assuming the open pipe end to be the face of a clock; the support should be at least from 4:00 to 8:00. Suspended piping should have 180 degrees of support, and if held tightly in a clamp type device, the support would be 360 degrees. Where metal supports or bands are utilized, a resilient padding such as neoprene or rubber must be used to protect the pipe from damage by the supports.

SPACING

The designer may wish to refer to Section D for further understanding of the effects of temperature on a pipeline. For determination on support spacing, the following formula11 can be used to estimate the distance between anchor or support points:

(40)

or

(41)

Where Δy = Sag of pipe at the lowest point, feet ρp = Density of pipe, lbs/ft3 (0.955 for HDPE) ρf = Fluid density, lbs/ft3 E = Modulus of elasticity, lbs/in2 L = Distance between supports, feet D = Outside diameter, inches d = Inside diameter, inches

NOTE: As previously stated, a pipeline operating continuously at or above 150ºF should have continuous support.


( )( )( )44

42220651.0dDE

LddDy fp

−⋅⋅⋅+−⋅⋅

=Δρρπ

( )( )( )

4/1

222

44

0651.0 ⎥⎥⎦

⎤

⎢⎢⎣

⎡

⋅+−⋅⋅Δ⋅−⋅

=ddD

ydDELfp ρρπ

J-2PolyPipe 12/05

INSTALLATION

A buried piping system, by virtue of the continuous contact of the backfill material and the reduction of temperature fluctuation due to environment, needs no further special consideration. Pipe-to-soil friction will effectively retain the buried pipe in place. However, the above ground pipeline does not have these restraints; therefore, the thermal expansion/contraction must be allowed for by different means. With a change in temperature, an amount of expansion/contraction will occur, and it is necessary to ensure that this effect is accommodated for so that no adverse effects are experienced. Change in length of pipeline due to thermal changes can be accommodated for in one of the following ways: 1. The pipeline can be allowed to move freely as its physical restraints allow. 2. It may be anchored closely and tightly so that unit changes take place in the elasticity of the material rather

than transferring all the forces to one point. 3. Ends and changes in direction may be anchored and expansion loops installed at or near the midpoint of the

run. An above ground pipeline should be placed in the shade, if possible, in order to minimize the effect of sun influenced temperature; therefore, the amount of thermal expansion that occurs.


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NATURAL GAS FLOW Natural gas distribution piping shall be designed and installed in accordance with all applicable federal, state and local codes. Current law limits the design pressure rating to 125 psig for plastic pipe used in distribution systems or Class 3 or 4 locations. Please refer to the Code of Federal Regulations (CFR), Parts 186 – 199 for additional information. The inside surface of PolyPipe® is extremely smooth and has a very low coefficient of friction. HDPE’s flow resistance is considerably less than that of steel pipe. There is minimal drag on the pipe wall and due to polyethylene’s exceptional resistance to corrosion there is little deterioration of the piping surface due to the presence of aggressive media, both inside and outside of the pipe. Polyethylene pipe will maintain these advantages for its entire service life, up to 50 years or more. Due to the physical properties of polyethylene and the extremely smooth bore surface, it would appear only natural to assume that polyethylene pipe would have significantly higher flow capacity. While this would be true in water service systems, where the flow is fully turbulent, it is not entirely true in gas service systems, where the flow is partially turbulent. The initial flow capacities for polyethylene and steel are similar; however, as the pipe ages, the steel pipe can begin to corrode. Once this happens, the flow capacity for the steel pipe begins to decrease dramatically. Therefore, for comparison purposes of performance over the service lives of the two pipes, polyethylene would provide for a longer life. Steel and polyethylene pipe have similar flow capacities. It has been found that flow formulas developed for sizing of steel pipe are applicable for sizing of polyethylene pipe. However, consideration must be given to differences in inside diameter.

Table L-1

TYPICAL MAXIMUM FLOW RATES EXPERIENCED IN 60 PSI NATURAL GAS DISTRIBUTION SYSTEMS

Nominal Inside Pipe Diameter,

Inches Maximum Flow Rates,

Mcfh (thousand cubic feet per hour) 2 17.4 3 43.5 4 81.1 6 163 10 556

Any of the accepted gas flow equations used with steel pipe, such as Mueller, Pole, Weymouth, Spitzglass, or the IGT Distribution Equation, can be used for calculations of polyethylene pipe flow capacities. It should be noted that no direct formulas provide the proper modifier to account for the extremely low coefficient of friction, which is characteristic of polyethylene. The IGT Distribution Equation13, shown below, is thought to be representative of polyethylene for most distribution design situations.

(42)

Where Q = Volumetric flow rate, MSCFH Tb = Base temperature, oR (Rankine) Pb = Base pressure, psia P1 = Upstream pressure, psia P2 = Downstream pressure, psia L = Length of pipe section, feet T = Average fluid temperature, oR (Rankine) μ = Viscosity, lb/ft-sec d = Inside diameter, inches SG = Specific gravity, dimensionless

13 American Gas Association. Plastic Pipe Manual for Gas Service, 2001.

( )

⎟⎟⎠

⎞⎜⎜⎝

⎛⎥⎦

⎤⎢⎣

⎡

⋅−

⎟⎟⎠

⎞⎜⎜⎝

⎛⋅=

91

94

38

95

22

216643.0

μSG

dLTPP

PTQ

b

b

L-1PolyPipe 12/05

In order to supply our customers with the best possible tools upon which to base a design decision, the formulae that follow represent a sampling of other acceptable equations that can be utilized for the determination of gas flow capacity. These include the Mueller, Weymouth, and Spitzglass1 equations. They are as follows: Mueller Equation:

(43)

Weymouth Equation:

(44) Spitzglass Equation:

(45)

PIPE COILING Over the last 30 years, the demanding growth of polyethylene pipe for natural gas distribution systems and the technical advances in construction practice have greatly increased the need for longer continuous lengths of product. Coiling of pipe in sizes up to 6” nominal OD are now standard practice and readily available. Standard coil lengths of 150’, 250’, 500’, and even larger lengths in smaller diameters have become acceptable product. Due to the flexibility of polyethylene gas pipe, it can be coiled in this manner without damage to the pipe. However, it is prudent to advise that this can pose a safety concern if the pipe is allowed to uncoil in an uncontrolled manner. Coiled polyethylene piping can store an incredible amount of potential energy that is released during the uncoiling of the pipe. This is an extremely important safety issue. Therefore, we cannot over stress the importance of cautious handling and installation of the piping regarding the safety of all concerned from off-loading the product to field installation personnel. PolyPipe® recommends the use of an uncoiling/rerounding device when handling coiled polyethylene pipe.

PIPE CURVATURE

In the construction of long distance runs of piping it is often necessary to negotiate bends and/or curves. The natural flexibility of polyethylene piping, as mentioned previously, allows runs of piping to be routed around obstacles in a fairly tight radius. Therefore, with proper planning, trenches can be excavated in such a manner to accommodate bends and/or curves that are within the capabilities of the pipe. To determine the cold bend radius of polyethylene pipe, OD/t, refer to Section F, Underground Installation, Table F-1.


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L-2PolyPipe 12/05

INSTALLATION Prior to installation, an inspection should be completed of the pipe. Surface damage can occur during construction handling and the installation process. Significant damage may impair the performance capabilities of the pipeline. The following guidelines, as taken from the PPI Engineering Handbook, may be used to assess surface damage significance. For pressure applications, surface damage or butt fusion misalignment should not exceed 10% of the minimum wall thickness required for the pipeline’s operating pressure. Deep cuts, abrasions or grooves cannot be field repaired by hot gas or extrusion welding. Excessive damage may require removal and replacement of the damaged section. Misaligned butt fusions should be cut out and redone. If damage is not significant, the shape of the damage may be a consideration. Sharp notches and cuts should be dressed smooth so the notch is blunt. Blunt scrapes or gouges should not require attention. Minor surface abrasion from sliding on the ground or insertion into a casing should not be of concern. For proper installation of polyethylene pipe for gas service, please refer to the American Gas Association Plastic Pipe Manual.

L-3PolyPipe 12/05

L-4PolyPipe 12/05


9 0.64 16.31 0.093 2.37 0.094 0.1401/2 0.840 21.34 9.3 0.65 16.47 0.090 2.29 0.092 0.136

11 0.68 17.22 0.076 1.94 0.079 0.117

9 0.80 20.39 0.117 2.96 0.147 0.2199.3 0.81 20.59 0.113 2.87 0.143 0.213

3/4 1.050 26.67 11 0.85 21.53 0.095 2.42 0.123 0.18311.5 0.86 21.75 0.091 2.32 0.118 0.176

9 1.01 25.53 0.146 3.71 0.231 0.3439.3 1.02 25.79 0.141 3.59 0.224 0.334

1 1.315 33.40 11 1.06 26.96 0.120 3.04 0.193 0.28811.5 1.07 27.24 0.114 2.90 0.186 0.277

9 1.27 32.23 0.184 4.68 0.368 0.5479.3 1.28 32.55 0.178 4.53 0.357 0.532

1 1/4 1.660 42.16 11 1.34 34.04 0.151 3.83 0.308 0.45911.5 1.35 34.39 0.144 3.67 0.296 0.44113.5 1.40 35.54 0.123 3.12 0.256 0.381

9 1.45 36.89 0.211 5.36 0.482 0.7179.3 1.47 37.26 0.204 5.19 0.468 0.697

1 1/2 1.900 48.26 11 1.53 38.96 0.173 4.39 0.404 0.60111.5 1.55 39.36 0.165 4.20 0.388 0.57713.5 1.60 40.68 0.141 3.57 0.335 0.499

9 1.82 46.12 0.264 6.70 0.753 1.1209.3 1.83 46.57 0.255 6.49 0.732 1.089

2 2.375 60.33 11 1.92 48.70 0.216 5.48 0.631 0.93911.5 1.94 49.20 0.207 5.25 0.606 0.90213.5 2.00 50.85 0.176 4.47 0.524 0.78017 2.08 52.80 0.140 3.55 0.424 0.630

9 2.68 67.96 0.389 9.88 1.635 2.4339.3 2.70 68.63 0.376 9.56 1.589 2.364

3 3.500 88.90 11 2.83 71.77 0.318 8.08 1.370 2.03911.5 2.85 72.51 0.304 7.73 1.317 1.95913.5 2.95 74.94 0.259 6.59 1.138 1.69417 3.06 77.81 0.206 5.23 0.920 1.369

9 3.44 87.38 0.500 12.70 2.702 4.0229.3 3.47 88.24 0.484 12.29 2.626 3.909

4 4.500 114.30 11 3.63 92.27 0.409 10.39 2.265 3.37011.5 3.67 93.23 0.391 9.94 2.176 3.23913.5 3.79 96.35 0.333 8.47 1.882 2.80017 3.94 100.05 0.265 6.72 1.521 2.263


Table L-2

Weight

PIPE WEIGHTS AND DIMENSIONS (IPS)PE2406 (YELLOW)


L-5PolyPipe 12/05


9 4.25 108.02 0.618 15.70 4.130 6.1469.3 4.29 109.09 0.598 15.19 4.014 5.973

5 5.563 141.30 11 4.49 114.07 0.506 12.85 3.461 5.15111.5 4.54 115.25 0.484 12.29 3.326 4.94913.5 4.69 119.11 0.412 10.47 2.876 4.28017 4.87 123.68 0.327 8.31 2.324 3.458

9 5.06 128.64 0.736 18.70 5.857 8.7169.3 5.11 129.92 0.712 18.09 5.693 8.472

6 6.625 168.28 11 5.35 135.84 0.602 15.30 4.909 7.30511.5 5.40 137.25 0.576 14.63 4.717 7.02013.5 5.58 141.85 0.491 12.46 4.079 6.07017 5.80 147.29 0.390 9.90 3.296 4.905

9 5.45 138.35 0.792 20.11 6.775 10.0829.3 5.50 139.72 0.766 19.46 6.584 9.799

7 7.125 180.98 11 5.75 146.10 0.648 16.45 5.677 8.44911.5 5.81 147.61 0.620 15.74 5.456 8.11913.5 6.01 152.56 0.528 13.41 4.717 7.02017 6.24 158.41 0.419 10.65 3.812 5.673

9 6.59 167.47 0.958 24.34 9.927 14.7749.3 6.66 169.14 0.927 23.56 9.649 14.359

8 8.625 219.08 11 6.96 176.85 0.784 19.92 8.320 12.38111.5 7.04 178.69 0.750 19.05 7.995 11.89813.5 7.27 184.67 0.639 16.23 6.913 10.28717 7.55 191.76 0.507 12.89 5.586 8.313

Table L-2 (cont'd)

Weight

PIPE WEIGHTS AND DIMENSIONS (IPS)PE2406 (YELLOW)


lb. per kg. perSize in. mm. in. mm. foot meter

1/2 x 0.090 0.625 15.88 0.43 11.03 0.065 0.097

3/4 x 0.090 0.875 22.23 0.68 17.38 0.096 0.142

1 x 0.090 1.125 28.58 0.93 23.73 0.126 0.188

1 x 0.099 1.125 28.58 0.92 23.24 0.137 0.205

ODOD Nominal ID

Table L-3

Weight

PIPE WEIGHTS AND DIMENSIONS (CTS)PE2406 (YELLOW)

HANDLING AND STORAGE

After the piping system has been designed and specified, the piping system components must be obtained. Typically, project management and purchasing personnel work closely together so that the necessary components are available when they are needed for the upcoming construction work.

UNLOADING INSTRUCTIONS

Before unloading the shipment, there must be adequate, level space to unload the shipment. The truck should be on level ground with the parking brake set and the wheels chocked. Unloading equipment must be capable of safely lifting and moving pipe, fittings, fabrications or other components. WARNING: Unloading and handling must be performed safely. Unsafe handling can result in damage to property or equipment, and be hazardous to persons in the area. Keep unnecessary persons away from the area during unloading. WARNING: Only properly trained personnel should operate unloading equipment.

UNLOADING SITE REQUIREMENTS

The unloading site must be relatively flat and level. It must be large enough for the carrier's truck, the load handling equipment and its movement, and for temporary load storage. Silo packs and other palletized packages should be unloaded from the side with a forklift. Non-palletized pipe, fittings, fabrications, manholes, tanks, or other components should be unloaded from above with lifting equipment and wide web slings, or from the side with a forklift.

HANDLING EQUIPMENT Appropriate unloading and handling equipment of adequate capacity must be used to unload the truck. Safe handling and operating procedures must be observed. Pipe must not be rolled or pushed off the truck. Pipe, fittings, fabrications, tanks, manholes, and other components must not be pushed or dumped off the truck, or dropped. Although polyethylene-piping components are lightweight compared to similar components made of metal, concrete, clay, or other materials, larger components can be heavy. Lifting and handling equipment must have adequate rated capacity to lift and move components from the truck to temporary storage. Equipment such as a forklift, a crane, a side boom tractor, or an extension boom crane is used for unloading. When using a forklift, or forklift attachments on equipment such as articulated loaders or bucket loaders, lifting capacity must be adequate at the load center on the forks. Forklift equipment is rated for a maximum lifting capacity at a distance from the back of the forks. (See Figure M-1.) If the weight-center of the load is farther out on the forks, lifting capacity is reduced. Before lifting or transporting the load, forks should be spread as wide apart as practical, forks should extend completely under the load, and the load should be as far back on the forks as possible. WARNING: During transport, a load on forks that are too short or too close together, or a load too far out on the forks, may become unstable and pitch forward or to the side, and result in damage to the load or property, or hazards to persons. Lifting equipment such as cranes, extension boom cranes, and side boom tractors, should be hooked to wide web choker slings that are secured around the load or to lifting lugs on the component. Only wide web slings should be used. Wire rope slings and chains can damage components, and should not be used. Spreader bars should be used when lifting pipe or components longer than 20 feet. WARNING: Before use, inspect slings and lifting equipment. Equipment with wear or damage that impairs function or load capacity should not be used.

M-1PolyPipe 12/05

Figure M-1 FORKLIFT LOAD CAPACITY

Unloading Large Fabrications, Manholes and Tanks

Large fabrications, manholes and tanks should be unloaded using a wide web choker sling and lifting equipment such as an extension boom crane, crane, or lifting boom. The choker sling is fitted around the manhole riser or near the top of the tank. Do not use stub outs, outlets, or fittings as lifting points, and avoid placing slings where they will bear against outlets or fittings. Larger diameter manholes and tanks are typically fitted with lifting lugs. WARNING: ALL lifting lugs must be used. The weight of the manhole or tank is properly supported only when all lugs are used for lifting. Do not lift tanks or manholes containing liquids.

Pre-Installation Storage

The size and complexity of the project and the components, will determine pre-installation storage requirements. For some projects, several storage or staging sites along the right-of-way may be appropriate, while a single storage location may be suitable for another job. The site and its layout should provide protection against physical damage to components. General requirements are for the area to be of sufficient size to accommodate piping components, to allow room for handling equipment to get around them, and to have a relatively smooth, level surface free of stones, debris, or other material that could damage pipe or components, or interfere with handling. Pipe may be placed on 4-inch wide wooden dunnage, evenly spaced at intervals of 4 feet or less.

Pipe Stacking Heights Coiled pipe is best stored as received in silo packs. Individual coils may be removed from the top of the silo pack without disturbing the stability of the remaining coils in the silo package. Pipe received in bulk packs or strip load packs should be stored in the same package. If the storage site is flat and level, bulk packs or strip load packs may be stacked evenly upon each other to an overall height of about 6 feet. For less flat or less level terrain, limit stacking height to about 4 feet. Before removing individual pipe lengths from bulk packs or strip load packs, the pack must be removed from the storage stack, and placed on the ground. Individual pipes may be stacked in rows. Pipes should be laid straight, not crossing over or entangled with each other. The base row must be blocked to prevent sideways movement or shifting (See Table M-1). The interior of stored pipe should be kept free of debris and other foreign matter.

M-2PolyPipe 12/05

Table M-1 LOOSE PIPE STORAGE

Suggested Stacking Height* - Rows Pipe Size, Nominal DR Above 17 DR 17 & Below

4 15 12 5 12 10 6 10 8 8 8 6

10 6 5 12 5 4 14 5 4 16 4 3 18 4 3 20 3 3 22 3 2 24 3 2 26 3 2 28 2 2 30 2 2 32 2 2 36 2 1 42 1 1 48 1 1 54 1 1 63 1 1

*NOTE: Stacking heights based on 6 feet for level terrain and 4 feet for less level terrain.

Exposure to UV and Weather

Polyethylene pipe products are protected against deterioration from exposure to ultraviolet light and weathering effects. Color and black products are compounded with antioxidants, thermal stabilizers and UV stabilizers. Color products use sacrificial UV stabilizers that absorb UV energy and are eventually depleted. In general, non-black products should not remain in unprotected outdoor storage for more than two years; however, some manufacturers may allow longer unprotected outside storage. Black products contain at least 2% carbon black to protect the material from UV deterioration. Black products with and without stripes are generally suitable for unlimited outdoor storage and for service on the surface or above grade.

Cold Weather Handling

Temperatures near or below freezing will affect polyethylene pipe by reducing flexibility and increasing vulnerability to impact damage. Care should be taken not to drop pipe, or fabricated structures, and to keep handling equipment and other things from hitting pipe. Ice, snow, and rain are not harmful to the material, but may make storage areas more troublesome for handling equipment and personnel. Unsure footing and traction require greater care and caution to prevent damage or injury.

Walking on pipe can be dangerous. Inclement weather can make pipe surfaces especially slippery. WARNING: Keep safety first on the jobsite; do not walk on pipe. All of the above information has been printed with permission of the Plastics Pipe Institute. The information is available in the Engineering Handbook; Inspections, Test and Safety Concerns.


M-3

PolyPipe 12/05

CONVERSION FACTORS

METRIC TO ENGLISH

To obtain:

Multiply:

By:

Inches Centimeters 0.3937 Inches Millimeters 0.03937

Feet Meters 3.281 Yards Meters 1.094 Miles Kilometers 0.6214

Ounces Grams 352.74 Pounds Kilometers 2.205

Gallons (U.S. Liquid) Liters 0.264 Fluid Ounces Milliliters (cc) 338.14

Square Inches Square Centimeters 0.155 Square Feet Square Meters 10.764

Square Yards Square Meters 1.196 Cubic Inches Milliliters (cc) 610.24 Cubic Feet Cubic Meters 35.315 Cubic Yards Cubic Meters 1.308

Pounds/Cubic Feet Kilograms/Cubic Meter 0.0624 Gallons/Minute Cubic Meters/Minute 0.00378

ENGLISH TO METRIC

To obtain:

Multiply:

By:

Microns Mils 25.4 Centimeters Inches 2.54 Millimeters Inches 25.4

Meters Feet 0.3048 Meters Yards 0.9144

Kilograms Miles 1.609 Grams Ounces 28.350

Kilograms Pounds 0.456 Liters Gallons (U.S. Liquid) 3.785

Milliliters (cc) Fluid Ounces 29.574 Square Centimeters Square Inches 6.452

Square Meters Square Feet 0.0929 Square Meters Square Yards 0.936 Milliliters (cc) Cubic Inches 16.387 Cubic Meters Cubic Feet 0.02832 Cubic Meters Cubic Yards 0.765

Cubic Meters/Minute Gallons/Minute 264.86

N-1PolyPipe 12/05

GENERAL

To obtain:

Multiply:

By:

Atmospheres Feet of water @ 4°C 0.0295 Atmospheres Inches of mercury @ 0°C 0.0342

PSI Inches of mercury @ 0°C .2049 Atmospheres Pounds per square inch 0.06804

BTU Foot-pounds 0.01285 BTU Joules 0.09348

Cords Cubic Feet 128 MPa Pounds per square inch 0.006897

Pounds per Square Inch MPa 145 Degree (angle) Radians 57.2958

Ergs Foot-Pounds 1.356 x 107 Feet Miles 5280

Feet of Water @ 4°C Atmosphere 33.90 Foot-pounds Horsepower-hours 1.98 x 106 Foot-pounds Kilowatts-hours 2.655 x 106

Foot-pounds per minute Horsepower 3.3 x 106 Horsepower Foot-pounds per second 1,818

Inches of Mercury @ 0°C Pounds per square inch 2.036 Joules BTU 1054.8 Joules Foot-pounds 1.35582

Kilowatts BTU per minute 0.01758 Kilowatts Foot-pounds per minute 0.0000226 Kilowatts Horsepower 0.7457

Knots Miles per hour 0.869 Miles Feet 0.0001894

Nautical Miles Miles 0.869 Radians Degrees 0.01745

Square Feet Acres 43,560 Watts BTU per minute 17.5796

Pounds per Square Inch Feet of water @ 4°C 0.4335

N-2PolyPipe 12/05

TEMPERATURE FACTORS

T(°F) = 1.8T(°C) + 32 T(°C) = [T(°F) -32]/1.8

T(oR) = 1.8T(K) T(K) = T(oC) + 273.15 T(oR) = T(oF) + 459.67

Centigrade scales and Celsius scales are interchangeable.

DECIMAL EQUIVALENTS OF FRACTIONS OF AN INCH

1/64 = 0.015 11/32 22/64 = 0.343 43/64 = 0.671 1/32 2/64 = 0.031 23/64 = 0.359 11/16 22/32 44/64 = 0.687 3/64 = 0.046 3/8 12/32 24/64 = 0.375 45/64 = 0.703

1/16 2/32 4/64 = 0.625 25/64 = 0.390 23/32 46/64 = 0.718 5/64 = 0.078 13/32 26/64 = 0.406 47/64 = 0.734 3/32 6/64 = 0.093 27/64 = 0.421 3/4 24/32 48/64 = 0.750 7/64 = 0.109 7/16 14/32 28/64 = 0.437 49/64 = 0.765

1/8 4/32 8/64 = 0.125 29/64 = 0.453 25/32 50/64 = 0.781 9/64 = 0.140 15/32 30/64 = 0.468 51/64 = 0.796 5/32 10/64 = 0.156 31/64 = 0.484 13/16 26/32 52/64 = 0.812 11/64 = 0.171 1/2 16/32 32/64 = 0.500 53/64 = 0.828

3/16 6/32 12/64 = 0.187 33/64 = 0.515 27/32 54/64 = 0.843 13/64 = 0.203 17/32 34/64 = 0.531 55/64 = 0.859 7/32 14/64 = 0.218 35/64 = 0.546 7/8 28/32 56/64 = 0.875 15/64 = 0.234 9/16 18/32 36/64 = 0.562 57/64 = 0.890

1/4 8/32 16/64 = 0.250 37/64 = 0.578 29/32 58/64 = 0.906 17/64 = 0.265 19/32 38/64 = 0.593 59/64 = 0.921 9/32 18/64 = 0.281 39/64 = 0.609 15/16 30/32 60/64 = 0.937 19/64 = 0.296 5/8 20/32 40/64 = 0.625 61/64 = 0.953

5/16 10/32 20/64 = 0.312 41/64 = 0.640 31/32 62/64 = 0.968 21/64 = 0.328 21/32 42/64 = 0.656 63/64 = 0.984


N-3PolyPipe 12/05

MATERIAL SAFETY DATA SHEET

SECTION 1 - IDENTIFICATION Yellow MDPE Pipe All Other Products

Trade Name: 3810 PE2406 Gas Pipe Trade Name: PolyPipe® EHMW, PolyPlus™, Lightview™, 7810 Gas Pipe, Warning: Do not use for potable water. 6810 Gas Pipe, 4810 Gas Pipe, PolyPipe® PW Classification: Classification: ASTM D3350 PE234363E ASTM D3350 PE234463C, D or E (2406) PE345464C, D or E (3408) ASTM D1248 Type II, Class B, Category 5, ASTM D1248 Type II, Class B, Category 5, (obsolete) Grade P23/P24 (obsolete) Grade P23/P24 (2406) Type III, Class C, Category 5, Grade 34 (3408)

SECTION 2 – PHYSICAL DATA

Yellow MDPE Pipe All Other Products 2a Appearance: ½” – 24” diameter yellow 2a Appearance: ½” – 54” diameter black or pipe either coiled or cut colored pipe either coiled or to length cut to length 2b Odor: Odorless 2b Odor: Odorless 2c Boiling Point: N/A 2c Boiling Point: N/A 2d Solubility: Insoluble in water 2d Solubility: Insoluble in water 2e Evaporation: N/A 2e Evaporation: N/A 2f Density: 0.943 g/cm3 @ 230C 2f Density: 0.947 - 0.960 g/cm3 @ 230C 2g Vapor Pressure: N/A 2g Vapor Pressure: N/A 2h Melting Point: 230 – 275oF 2h Melting Point: 230 – 275oF 2i Vapor Density: N/A 2i Vapor Density: N/A 2j Percent Volatile: Negligible 2j Percent Volatile: <0.03%

SECTION 3 – HEALTH HAZARD INFORMATION

Yellow MDPE or Colored HDPE Pipe Black Products 3a Hazardous Components: 3a Hazardous Components:

Lead Chromate Pigment – CAS # 1344-37-2 Lead Chromate – CAS # 7758-97-6 Cadmium – CAS# 7440-43-9

Carbon black– CAS # 1333-86-4

3b Exposure Limits: 3b Exposure Limits: OSHA Permissable Exposure Limit: OSHA Permissable Exposure Limit:

Cadmium 5 mg/m3 respirable dust 15 mg/m3 total dust 5μg/m3 cadmium

5 mg/m3 respirable dust 15 mg/m3 total dust

Lead and Chromium

5 mg/m3 respirable dust 15 mg/m3 total dust 0.5 mg/m3 chromium 0.05 mg/m3 lead

ACGIH limits exposure to 10mg/m3 total dust.

PolyPipe® yellow gas products may contain either lead chromate or cadmium. Both of these products are known to be a probable human carcinogen.

Avoid breathing dust or fumes that may be generated during cutting or fusing of pipe.

3c Overexposure: Repeated and prolonged exposure to dust or fumes that may be generated during cutting and fusing of pipe may cause delayed effects involving blood, gastrointestinal, nervous and reproductive systems. See Section 4 for Emergency First Aid Procedures.

P-1

PolyPipe 12/05

SECTION 4 – EMERGENCY AND FIRST AID PROCEDURES Yellow MDPE Pipe All Other Products

4a Inhalation: 4a Inhalation:

The material is not expected to present an acute inhalation hazard. If exposed to fumes from overheating or combustion, move to fresh air. Consult a physician if symptoms persist.

The material is not expected to present an acute inhalation hazard. If exposed to fumes from overheating or combustion, move to fresh air. Consult a physician if symptoms persist.

4b Eyes: 4b Eyes:

Immediately flush polymer fines from eyes with water for several minutes; seek medical attention.

Immediately flush polymer fines from eyes with water for several minutes; seek medical attention.

4c Skin: 4c Skin:

Cool skin rapidly if contacted with molten polymer without attempting to remove molten material. Obtain medical attention for thermal burns.

Cool skin rapidly if contacted with molten polymer without attempting to remove molten material. Obtain medical attention for thermal burns.

4d Ingestion: 4d Ingestion:

Products containing cadmium are harmful if ingested due to the toxicity of cadmium. Seek medical attention.

Few or no adverse health effects from ingestion. Seek medical attention if pain develops.

SECTION 5 – FIRE AND EXPLOSION DATA

Yellow MDPE Pipe All Other Products 5a Flash Point: >650oF (ASTM E136) 5a Flash Point: >650oF (ASTM E136) 5b Upper Explosive

Limit: Not determined 5b Upper Explosive Limit: Not determined

5c Lower Explosive Limit: Not determined 5c Lower Explosive

Limit: Not determined

5d Auto ignition temperature >650oF (estimated) 5d Auto ignition

temperature >650oF (estimated)

5e Extinguishing Media 5e Extinguishing Media

Dry chemical, water fog, foam, carbon dioxide Dry chemical, water fog, water spray, foam, carbon dioxide

5f Special fire & explosion hazards 5f Special fire & explosion hazards Dense smoke emitted when burned without

sufficient oxygen. Possible dust explosion if fines accumulate. Wear standard fire fighting equipment.

Dense smoke emitted when burned without sufficient oxygen. Possible dust explosion if fines accumulate. Wear standard fire fighting equipment.

5g NFPA Ratings 5g NFPA Ratings Health 1; Flammability 1; Reactivity 0 Health 0; Flammability 1; Reactivity 0

SECTION 6 – ACCIDENTAL RELEASE MEASURES

All Products 6a Environmental Precautions: Prevent discharges of spilled material with mixing in soil and prevent runoff to surface waters. Avoid

creating dust and prevent wind dispersion. 6b Land Spill: Spilled material should be swept up and discarded. Comply with applicable federal, state and local

regulations. 6c Water Spill: Advise local authorities if spilled in waterway or sewer. Skim from surface of water if possible. 6d Waste Disposal: Dispose in accordance with federal, state and local regulations.

P-2PolyPipe 12/05

SECTION 7 – STORAGE AND HANDLING All Products

7a Do not store pipe near heat, flame or strong oxidants, such as chlorates, nitrates, peroxides, etc. May react with halogens.

7b See 9d below for incompatibility with other materials. 7c Maximum recommended storage life for yellow PE2406 3810 Gas Pipe or other colored products,

excluding black, is three years from date of manufacture.

SECTION 8 – PROTECTIVE MEASURES All Products

8a Cleanup Procedures: Sweep and collect in suitable container for disposal. 8b Waste Disposal Method:

This product is not considered a RCRA hazardous waste. Dispose of in accordance with local, state and federal regulations.

8c Respiratory Protection: Use NIOSH approved respirator if unable to control airborne dust, fumes or vapors.

8d Protective Clothing: Wear gloves and suitable eye protection. 8e Ventilation: Local exhaust ventilation is recommended for control of airborne dust, fumes

and vapors, particularly in confined areas.

SECTION 9 – REACTIVITY All Products

9a Stability: Material is stable. 9b Hazardous

Polymerization: Hazardous polymerization will not occur.

9c Conditions to Avoid: Avoid prolonged exposure to temperatures over 480oF (250oC). Do not heat without proper ventilation.

9d Incompatibility with Other Materials:

Avoid storage or contact with strong oxidizing agents.

9e Combustion Products: Combustion products generated during processing include: carbon dioxide, carbon monoxide, water vapor and trace amounts of volatile organic compounds. Carbon monoxide is highly toxic if inhaled. Carbon dioxide in sufficient concentrations can act as an asphyxiant. Acute overexposure to the products of combustion may result in irritation of the respiratory tract.

PolyPipe® urges the customer receiving this Material Safety Data Sheet to study it carefully to become aware of potential hazards, if any, of the products involved. In the interest of safety you should (1) furnish your employees, agents and contractors with this sheet, (2) furnish a copy to each of your customers for their product and (3) request your customer to inform their employees and customers as well.

CHEMTREC EMERGENCY NUMBER (800) 424-9300

NOTE: Hazard data contained herein was obtained from raw material suppliers. TO THE BEST OF OUR KNOWLEDGE THE INFORMATION CONTAINED IN THIS MATERIAL SAFETY DATA SHEET IS ACCURATE. HOWEVER, NEITHER PolyPipe, Inc., NOR ANY OF ITS AFFILIATES MAKE ANY WARRANTY, EXPRESS OR IMPLIED, OR ACCEPTS ANY LIABILITY IN CONNECTION WITH THIS INFORMATION OR ITS USE.

P-3PolyPipe 12/05

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C-1000Rev. 05/05

GAINESVILLE PLANT

P.O. Box 3902406 N. I-35Gainesville, TX 76241-0390(940) 665-1721(800) 433-5632Fax: (940) 668-8612Sales Fax: (940) 668-2704

FERNLEY PLANT

230 Lyon DriveFernley, NV 89408(775) 575-5454Fax: (775) 575-6960

ERWIN PLANT

P.O. Box 1991050 Industrial Drive SouthErwin, TN 37650(423) 743-9116Fax: (423) 743-8419

SANDERSVILLE PLANT

P.O. Box 784995 Waco Mill RoadSandersville, GA 31082(478) 553-0576

ROARING SPRINGS PLANT

P.O. Box 29811000 Hwy. 70 SouthRoaring Springs, TX 79256(806) 348-7551(877) 771-8330Fax: (806) 348-7905

KIMBALL PLANT

3405 PolyPipe RoadKimball, NE 69145(308) 235-4828Fax: (308) 235-2938

ISO 9001:2000

PolyPipe® is an active member of the Plastics Pipe Institute,AWWA, AGA and ASTM.

PolyPipe, Inc.2406 N. I-35 I P.O. Box 390 I Gainesville, TX 76241

Phone 940.665.1721 I 800.433.5632 I Facsimile 940.668.8612Sales Facsimile 940.668.2704 I www.polypipeinc.com

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Manual de Tuberia de Polietileno

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