Features and Benefits
PE63, PE80 & PE100. These 3 material grades have different properties which enable them to be classified with minimum required strengths (MRS) of 6.3 MPa, 8.0 MPa & 10.0 MPa respectively.
Applying a design coefficient of 1.25 (safety factor) to the MRS gives the design stress used by SABS ISO 4427 for these materials (5.0 MPa, 6.3 MPa & 8.0 MPa respectively) with the result that the wall thickness for a particular size & class become progressively lass as the change is made to a material with a higher MRS.
| Features | Benefits |
|---|---|
| Good impact strength | Little handling and installation damage |
| Excellent corrosion resistance | Long and efficient service life |
| Good chemical resistance | Wide range of applications |
| Low mass | Easy handling |
| Flexibility | Easy installation |
| Long lengths available | Fewer joints |
| Good abrasion resistance | Can be used to pump slurries |
| Low friction losses | Lower pumping costs |
| Several jointing methods | Wide variety of applications |
| Extensive range of fittings | Wide variety of installations |
| Nominal Working Pressure HDS 5 MPa PE 80 | PN 3.2 | PN4 | ||||||||||||||||||
| Nominal Working Pressure HDS 6.3 MPa PE 80 | PN 3.2 | PN 4 | PN 63 | |||||||||||||||||
| Nominal Working Pressure HDS 8 MPa PE 100 | PN 4 | PN 6.3 | PN 8 | |||||||||||||||||
| Standard Diameter Ratio (SDR) | SDR 41 | SDR 33 | SDR 26 | SDR 21 | ||||||||||||||||
| Norm Size mm | Mean Outside Diameter | Ovality Outside Diameter | Wall Thickness T | Pipe ID & Mass | Wall Thickness T | Pipe ID & Mass | Wall Thickness T | Pipe ID & Mass | Wall Thickness T | Pipe ID & Mass |
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| Min | Max | Min | Max | Min | Max | ID | Kg/m | Min | Max | ID | Kg/m | Min | Max | ID | Kg/m | Min | Max | ID | Kg/m | |
| 16 | 16 | 16.3 | 15.4 | 16.3 | 1.6 | 1.9 | 13 | 0.08 | 1.6 | 1.9 | 13 | 0.08 | 1.6 | 1.9 | 13 | 0.08 | 1.6 | 1.9 | 13 | 0.08 |
| 20 | 20 | 20.3 | 19.4 | 20.6 | 1.6 | 1.9 | 17 | 0.10 | 1.6 | 1.9 | 17 | 0.10 | 1.6 | 1.9 | 17 | 0.10 | 1.6 | 1.9 | 17 | 0.10 |
| 25 | 25 | 25.3 | 24.4 | 25.6 | 1.6 | 1.9 | 22 | 0.12 | 1.6 | 1.9 | 22 | 0.12 | 1.6 | 1.9 | 22 | 0.12 | 1.6 | 1.9 | 22 | 0.12 |
| 32 | 32 | 32.3 | 31.4 | 32.7 | 1.6 | 1.9 | 29 | 0.16 | 1.6 | 1.9 | 29 | 0.16 | 1.6 | 1.9 | 29 | 0.16 | 1.6 | 1.9 | 29 | 0.16 |
| 40 | 40 | 40.4 | 39.3 | 40.7 | 1.6 | 1.9 | 37 | 0.20 | 1.6 | 1.9 | 37 | 0.20 | 1.6 | 1.9 | 37 | 0.20 | 1.9 | 2.2 | 36 | 0.24 |
| 50 | 50 | 50.5 | 49.3 | 50.7 | 1.6 | 1.9 | 47 | 0.25 | 1.6 | 1.9 | 47 | 0.25 | 1.9 | 2.3 | 46 | 0.30 | 2.4 | 2.8 | 45 | 0.37 |
| 63 | 63 | 63.6 | 62.2 | 63.8 | 1.6 | 1.9 | 60 | 0.32 | 1.9 | 2.2 | 59 | 0.38 | 2.4 | 2.8 | 58 | 0.48 | 3.0 | 3.5 | 57 | 0.59 |
| 75 | 75 | 75.7 | 74.2 | 75.8 | 1.8 | 2.1 | 71 | 0.43 | 2.3 | 2.6 | 70 | 0.53 | 2.9 | 3.3 | 69 | 0.67 | 3.6 | 4.1 | 68 | 0.82 |
| 90 | 90 | 90.9 | 89.1 | 90.9 | 2.2 | 2.5 | 86 | 0.62 | 2.7 | 3.1 | 85 | 0.77 | 3.5 | 4.0 | 83 | 0.97 | 4.3 | 4.9 | 81 | 1.19 |
| 110 | 110 | 111.0 | 108.8 | 111.1 | 2.7 | 3.1 | 105 | 0.93 | 3.3 | 3.8 | 103 | 1.15 | 4.2 | 4.9 | 101 | 1.45 | 5.2 | 6.0 | 99 | 1.77 |
| 125 | 125 | 126.2 | 123.8 | 126.3 | 3.0 | 3.5 | 119 | 1.20 | 3.8 | 4.4 | 117 | 1.48 | 4.8 | 5.5 | 115 | 1.87 | 6.0 | 6.8 | 113 | 2.29 |
| 140 | 140 | 141.3 | 138.6 | 141.4 | 3.4 | 3.9 | 133 | 1.51 | 4.2 | 4.9 | 132 | 1.86 | 5.4 | 6.2 | 129 | 2.34 | 6.7 | 7.7 | 126 | 2.87 |
| 160 | 160 | 161.5 | 158.4 | 161.6 | 3.9 | 4.4 | 152 | 1.94 | 4.8 | 5.4 | 150 | 2.40 | 6.2 | 6.9 | 148 | 3.02 | 7.6 | 8.5 | 145 | 3.70 |
| 180 | 180 | 181.7 | 178.2 | 181.8 | 4.4 | 4.9 | 172 | 2.46 | 5.5 | 6.1 | 169 | 3.04 | 6.9 | 7.8 | 166 | 3.82 | 8.6 | 9.6 | 163 | 4.68 |
| 200 | 200 | 201.8 | 198.0 | 202.0 | 4.9 | 5.5 | 191 | 3.03 | 6.1 | 6.8 | 188 | 3.75 | 7.7 | 8.6 | 185 | 4,071 | 9.5 | 10.7 | 181 | 5.78 |
| 225 | 225 | 227.1 | 222.8 | 227.3 | 5.5 | 6.1 | 214 | 3.83 | 6.8 | 7.6 | 212 | 4.73 | 8.7 | 9.6 | 208 | 5.95 | 10.7 | 11.9 | 203 | 7.30 |
| 250 | 250 | 252.3 | 247.5 | 252.5 | 6.1 | 6.8 | 238 | 4.73 | 7.6 | 8.4 | 235 | 5.84 | 9.6 | 10.7 | 231 | 7.35 | 11.9 | 13.3 | 226 | 9.01 |
| 280 | 280 | 282.6 | 275.1 | 284.9 | 6.8 | 7.6 | 267 | 5.94 | 8.5 | 9.5 | 263 | 7.33 | 10.8 | 12.0 | 259 | 9.22 | 13.3 | 14.9 | 253 | 11.30 |
| 315 | 315 | 317.9 | 309.5 | 320.6 | 7.7 | 8.6 | 300 | 7.51 | 9.5 | 10.6 | 296 | 9.27 | 12.1 | 13.5 | 291 | 11.67 | 15.0 | 16.7 | 285 | 14.30 |
| 355 | 355 | 358.2 | 348.8 | 361.3 | 8.7 | 9.7 | 338 | 9.54 | 10.8 | 12.0 | 334 | 11.78 | 13.7 | 15.2 | 328 | 14.82 | 16.9 | 18.8 | 321 | 18.16 |
| 400 | 400 | 403.6 | 393.0 | 407.0 | 9.8 | 10.9 | 381 | 12.11 | 12.1 | 13.5 | 376 | 14.95 | 15.4 | 17.2 | 369 | 18.81 | 19.0 | 21.2 | 362 | 23.06 |
| 450 | 450 | 454.1 | 442.1 | 457.9 | 11.0 | 12.2 | 429 | 15.29 | 13.6 | 15.1 | 423 | 18.88 | 17.3 | 19.2 | 416 | 23.75 | 21.4 | 23.8 | 407 | 29.12 |
| 500 | 500 | 504.5 | 491.3 | 508.8 | 12.2 | 13.5 | 477 | 18.88 | 15.2 | 16.8 | 470 | 23.31 | 19.2 | 21.3 | 462 | 29.32 | 23.8 | 26.4 | 452 | 35.94 |
| 560 | 560 | 565.0 | 550.2 | 569.8 | 13.7 | 15.2 | 534 | 23.68 | 17.0 | 18.8 | 527 | 29.24 | 21.5 | 23.9 | 517 | 36.78 | 26.7 | 29.6 | 506 | 45.08 |
| 630 | 630 | 635.7 | 619.0 | 641.1 | 15.4 | 17.1 | 600 | 29.98 | 19.1 | 21.2 | 593 | 37.01 | 24.2 | 26.9 | 582 | 46.56 | 30.0 | 33.3 | 570 | 57.07 |
| Designation of Material | MRS at 50 years & 20°C (MPa) | Maximum allowable hydrostatic design stress (MPa) |
|---|---|---|
| PE 100 | 10 | 8 |
| PE 80 | 8 | 6.3 |
| PE 63 | 6.3 | 5 |
Coil Dimensions
Standard Coil Lengths
16 – 40mm : 100 metre coils
50 – 90mm : 50 & 100 metre coils
110mm : 50 metre coils
| O.D. [mm] | SDRs | I.D. I [mm] | O.D. D [mm] | Width W [mm] | ||
|---|---|---|---|---|---|---|
| Coil Length [m] | 50m | 100m | 50m | 100m |
||
| 16 | 7.4/9/11 | 600 | n/a | 860 | n/a | 180 |
| 20 | 7.4/9/11/13.6 | 600 | n/a | 860 | n/a | 180 |
| 25 | 7.4/9/11/13.6/17 | 600 | n/a | 890 | n/a | 200 |
| 32 | 7.4/9/11/13.6/17 | 700 | n/a | 1,090 | n/a | 220 |
| 40 | 7.4/9/11/13.6/17/26 | 700 | n/a | 1,090 | n/a | 220 |
| 50 | 7.4/9/11/13.6/17/26 | 1,300 | 1,410 | 1,560 | 150 | 220 |
| 63 | 7.4/9/11/13.6/17/26/33 | 1,300 | 1,780 | 1,960 | 190 | 280 |
| 75 | 7.4/9/11/13.6/17/26/33 | 1,300 | 1,780 | 1,960 | 190 | 280 |
| 90 | 7.4/9/11 | 2,500 | 3,100 | 3,300 | 270 | 360 |
| 13.6/17/21/26/33 | 1,800 | 2,360 | 2,540 | 360 | 450 | |
| 110 | 7.4/9/11 | 2,500 | 3,160 | n/a | 330 | n/a |
| 13.6/17/21/26/33 | 2,200 | 2,860 | n/a | 400 | n/a |
|
| PN 6.3 | PN 8 | PN 10 | PN 12.5 | PN 16 |
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| PN 8 | PN 10 | PN 12.5 | PN 16 | PN 20 |
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| PN 10 | PN 12.5 | PN 16 | PN 20 | ||||||||||||||||
| SDR 17 | SDR 13.6 | SDR 11 | SDR 9 | SDR 7.4 |
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| Wall thickness T | Pipe ID & Mass | Wall thickness T | Pipe ID & Mass | Wall thickness T | Pipe ID & Mass | Wall thickness T | Pipe ID & Mass | Wall thickness T | Pipe ID & Mass |
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| Min | Max | ID | Kg/m | Min | Max | ID | Kg/m | Min | Max | ID | Kg/m | Min | Max | ID | Kg/m | Min | Max | ID | Kg/m |
| 1.6 | 1.9 | 13 | 0.08 | 1.6 | 1.9 | 13 | 0.08 | 1.6 | 1.9 | 13 | 0.08 | 1.8 | 2.1 | 12 | 0.08 | 2.2 | 2.5 | 11 | 0.10 |
| 1.6 | 1.9 | 17 | 0.10 | 1.6 | 1.9 | 17 | 0.10 | 1.8 | 2.1 | 16 | 0.11 | 2.2 | 2.6 | 15 | 0.13 | 2.7 | 3.2 | 14 | 0.15 |
| 1.6 | 1.9 | 22 | 0.12 | 1.8 | 2.2 | 21 | 0.14 | 2.3 | 2.7 | 20 | 0.17 | 2.8 | 3.3 | 19 | 0.20 | 3.4 | 4.0 | 18 | 0.24 |
| 1.9 | 2.2 | 28 | 0.18 | 2.4 | 2.8 | 27 | 0.23 | 2.9 | 3.4 | 26 | 0.27 | 3.6 | 4.2 | 24 | 0.33 | 4.3 | 5.1 | 23 | 0.39 |
| 2.4 | 2.8 | 35 | 0.29 | 2.9 | 3.4 | 34 | 0.35 | 3.6 | 4.3 | 32 | 0.43 | 4.4 | 5.2 | 31 | 0.51 | 5.4 | 6.3 | 28 | 0.60 |
| 2.9 | 3.4 | 44 | 0.45 | 3.7 | 4.3 | 42 | 0.55 | 4.5 | 5.3 | 40 | 0.67 | 5.6 | 6.5 | 38 | 0.80 | 6.8 | 7.9 | 36 | 0.94 |
| 3.7 | 4.3 | 55 | 0.72 | 4.6 | 5.4 | 53 | 0.88 | 5.7 | 6.7 | 51 | 1.06 | 7.0 | 8.2 | 48 | 1.27 | 8.5 | 10.1 | 45 | 1.50 |
| 4.4 | 5.1 | 66 | 1.00 | 5.5 | 6.3 | 63 | 1.23 | 6.8 | 7.8 | 61 | 1.50 | 8.3 | 9.6 | 57 | 1.78 | 10.1 | 11.7 | 54 | 2.11 |
| 5.3 | 6.1 | 79 | 1.45 | 6.6 | 7.6 | 76 | 1.78 | 8.2 | 9.4 | 73 | 2.16 | 10.00 | 11.5 | 69 | 2.57 | 12.2 | 14.0 | 64 | 3.04 |
| 6.5 | 7.4 | 97 | 2.16 | 8.1 | 9.3 | 93 | 2.66 | 10.0 | 11.5 | 89 | 3.22 | 12.2 | 14.1 | 84 | 3.84 | 14.9 | 17.1 | 79 | 4.53 |
| 7.4 | 8.5 | 110 | 2.79 | 9.2 | 10.6 | 106 | 3.43 | 11.4 | 13.1 | 101 | 4.16 | 13.9 | 16.0 | 96 | 4.96 | 16.9 | 19.4 | 89 | 5.86 |
| 8.2 | 9.5 | 123 | 3.50 | 10.3 | 11.8 | 119 | 4.30 | 12.7 | 14.6 | 113 | 5.21 | 15.6 | 17.9 | 107 | 6.22 | 18.9 | 21.8 | 100 | 7.34 |
| 9.4 | 10.5 | 141 | 4.51 | 11.8 | 13.2 | 136 | 5.55 | 14.5 | 16.3 | 130 | 6.72 | 17.8 | 19.9 | 123 | 8.02 | 21.6 | 24.2 | 115 | 9.48 |
| 10.6 | 11.9 | 158 | 5.71 | 13.2 | 14.8 | 153 | 7.02 | 16.4 | 18.3 | 146 | 8.51 | 20.0 | 22.4 | 138 | 10.16 | 24.3 | 27.2 | 129 | 12.00 |
| 11.8 | 13.2 | 176 | 7.05 | 14.7 | 16.5 | 170 | 8.66 | 18.2 | 20.4 | 162 | 10.50 | 22.2 | 24.9 | 154 | 12.53 | 27.0 | 30.3 | 144 | 14.81 |
| 13.2 | 14.8 | 198 | 8.90 | 16.5 | 18.4 | 191 | 10.95 | 20.5 | 22.8 | 183 | 13.27 | 25.0 | 27.9 | 173 | 15.83 | 30.4 | 33.9 | 162 | 18.71 |
| 14.7 | 16.4 | 220 | 10.99 | 18.4 | 20.5 | 212 | 13.51 | 22.7 | 25.3 | 203 | 16.38 | 27.8 | 31.0 | 192 | 19.55 | 33.8 | 37.7 | 180 | 23.10 |
| 16.5 | 18.4 | 246 | 13.79 | 20.6 | 23.0 | 238 | 16.95 | 25.5 | 28.4 | 227 | 20.54 | 31.1 | 34.7 | 216 | 24.52 | 37.8 | 42.2 | 201 | 28.97 |
| 18.5 | 20.7 | 277 | 17.45 | 23.2 | 25.8 | 267 | 21.45 | 28.6 | 31.9 | 256 | 26.00 | 35.0 | 39.0 | 242 | 31.03 | 42.6 | 47.5 | 226 | 36.67 |
| 20.9 | 23.3 | 312 | 22.16 | 26.1 | 29.1 | 301 | 27.24 | 32.3 | 36.0 | 288 | 33.01 | 39.4 | 44.0 | 273 | 39.41 | 48.0 | 53.5 | 255 | 46.56 |
| 23.5 | 26.2 | 352 | 28.13 | 29.4 | 32.8 | 340 | 34.58 | 36.4 | 40.5 | 325 | 41.91 | 44.4 | 49.6 | 308 | 50.03 | 54.1 | 60.3 | 324 | 59.11 |
| 26.5 | 29.4 | 396 | 35.52 | 33.1 | 336.7 | 382 | 43.68 | 40.9 | 45.4 | 366 | 52.94 | 50.0 | 55.5 | 347 | 63.19 | 60.8 | 67.5 | 74.67 | |
| 29.4 | 32.6 | 440 | 43.85 | 36.8 | 40.8 | 425 | 53.92 | 45.5 | 50.5 | 406 | 65.36 | 55.6 | 61.7 | 385 | 78.01 | ||||
| 32.9 | 36.6 | 493 | 55.00 | 41.2 | 45.7 | 476 | 67.63 | 50.9 | 56.5 | 455 | 81.97 | ||||||||
| 37.1 | 41.1 | 555 | 69.62 | 46.3 | 51.4 | 535 | 85.60 | 57.3 | 63.6 | 512 | 103.75 | ||||||||
Physical Properties
High Density Polyethylene (HDPE) is a thermoplastic material which is supplied by the manufacturer in a ‘ready to use’ pelletised form. There are several different grades available. The particular grades suitable for pipe manufacture are referred to as PE63, PE80, & PE100. The pipe manufacturer simply converts this material into pressure pipe.
Table Of Physical Properties
The properties given below are for HDPE pipe materials. It should be noted that many of these properties are relative to temperature and the duration of stress application.
| Property | Value | Unit | Test Method | Test Specimen |
|
|---|---|---|---|---|---|
| Density at 23¼C | 0.958 | g/cm3 | ISO 1183 | 10mm x 10mm x 4mm |
|
| Viscosity Number | 380 | ml/g | ISO 1628-3 | 0.1% solution of granules in decahydronaphthalene |
|
| Melt Flow Rate | MFR 190/5 | 0.23 | g/10min | ISO 1133 | granules sample weight 3g to 6g |
| MFR 190/21.6 | 6.5 | g/10min |
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| Tensile Properties | Yield Stress | 26 | N/mm2 | ISO 527 Test Rate 50mm/min | ISO 3167, 4mm thick (test specimen No. 3, 4mm thick according to DIN 53 455) |
| Elongation at Yield Stress | 10 | % | ISO 527 Test Rate 50mm/min |
||
| Tensile Modulus of Elasticity (secant between 0.05 & 0.25% strain) | 900 | N/mm2 | ISO 527 |
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| Tensile Creep Modulus (1 hour value) (1000 hour value) | 650 350 | N/mm2 N/mm2 | ISO 899 Test Load 2M/mm2 |
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| Flexural Properties | Flexural Creep Modulus (1 min value) | 1,100 | N/mm2 | DIN 54 852- Z4 σb = 2N/mm2 | 110mm x 10mm x 4mm loaded flat |
| Flexural Stress (3.5% deflection) | 20 | N/mm2 | ISO 178 test Rate 2mm/min | 80mm x 10mm x 4mm |
|
| Stiffness in Torsion | 180 | N/mm2 | DIN 53 447 | 60mm x 6.35mm x 3mm |
|
| Hardness | Ball Indentation Hardness | 41 | N/mm2 | ISO 2039 part 1 Test Load 132N | Sheet, 4mm |
| Shore Hardness D (3 sec value) 15 sec value) | 61 59 | ~ ~ | ISO 868 | Sheet, 6mm |
|
| Notched Impact Strength (test specimen from compression moulded sheet) | at 23°C | 20 | kJ/m2 | ISO 179/1eA | 80mm x 10mm x 4mm |
| at -30°C | 10 | ||||
| Vicat Softening Point | 67 | °C | ISO 306 | Sheet, 4mm |
|
| Oxidation Induction Time | 200°C in O2 | >60 | min. | ISO TR 10837 | Granules |
Comparison with other Materials
| Property | HDPE | PP | PVC | PVC - C* | PB* |
|---|---|---|---|---|---|
| Surface feel | Waxy | Waxy | Smooth | Smooth | Waxy |
| Appearance (water pipes) | Black | Pale grey- beige | Blue | Grey-beige | Black |
| Sound produced when dropped | Medium clatter | High clatter | High clatter | High clatter | Dull thud |
| Combustibility and appearance of flame | Bright flame: Drops continue to burn while falling | Bright flame: Drops continue to burn while falling | Carbonises in flame: extinguishes away from flame | Carbonises in flame: extinguishes away from flame | Bright flame: Drops continue to burn while falling |
| Odour of smoke after flame is extinguished | Like candles | Like resin | Pungent like hydrochloric acid | Pungent like hydrochloric acid | Like candles but more acrid than HDPE |
| Nail test Impression made by fingernail | Impression possible | Very slight impression possible | Impression not possible | Impression not possible | Impression easily produced |
| Special features | Smears when sawn |
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| Floats in water | Yes | Yes | No | No | Yes |
| Notch sensitivity | No | Slight | Yes | Yes | Yes |
| Weather resistance | Stabilised good | Stabilised good | Stabilised good | Stabilised good | Stabilised good |
| Method of pent joining | Fusion | Fusion | Solvent cement | Solvent cement | Fusion |
| Suitable for mechanical jointing | Yes | Yes | Yes | Yes | Yes |
| Stress crack sensitivity with regard to jointing for safe media e.g.water | Some | Slight | None | None | None |
| Linear expansion mm/m°C | 0.2 | 0.15 | 0.08 | 0.07 | 0.12 |
| Thermal conductivity kcal/mh°C | 0.40 | 0.19 | 0.14 | 0.14 | 0.20 |
| Specific heat kcal/mh°C | 0.42 | 0.4 | 0.23 | 0.23 | 0.47 |
| Specific weight Kg/cm2 | 0.955 | 0.905 | 1.42 | 1.5 | 0.92 |
| Tensile strength at 20°C | 240 | 320 | 550 | 550 | 200 |
| Modulus of elasticity at 20°C (kp/cm2) | 8,000 | 15,000 | 30,000 | 30,000 | 5,000 |
Expansion & Contraction
| Material | Coeffecient Of Expansion (K-1) |
|---|---|
| mPVC | 8 x 10-5 |
| HDPE | 20 x 10-5 |
| LDPE | 20 x 10-5 |
| Steel | 1.2 x 10-5 |
| Copper | 2.0 x 10-5 |
All plastics have high coefficients of expansion and contraction several times those of metals. This must be allowed for in any installation by the use of expansion joints, expansion loops etc.
The Stress Regression Line
The traditional method of portraying the primary mechanical property of HDPE, tensile strength, is by no means of a graph of log stress vs log time to failure. This is known as the stress regression line.
It is a plot of the circumferential hoop stress in the wall of the pipe (from internal pressure) against time to failure.
Numerous actual test results, measured at 20°C & 60°C, over a range of time up to 10,000 hours, are plotted on a log scale & a regression line is cancelled to fit this data. The resultant regression line is then extrapolated to 50 years (438,000 hours). The method of calculation is an internationally accepted procedure described in ISO/TR 9080. The required values of stress & time are specified in SABS ISO 4427.
The internationally accepted method for calculating circumferential hoop stress is derived from Barlow’s formula & is as follows:
Circumferential Hoop Stress σ = P(d-t)/2t
where P = internal pressure (MPa); t = minimum wall thickness (mm); d = mean external diameter (mm)
Stress Regression Curve
Jointing
One of the greatest features of HDPE pipes is the fact that a wide variety of jointing systems is available to suit a whole range of applications. The jointing systems can be divided into 2 main categories with further sub-divisions in each category.
Permanent Jointing
Non-Permanent / Detachable Jointing
