M-PVC & U-PVC - 1 M-PVC & U-PVC CATALOGUE

M-PVC & U-PVC - 1 M-PVC & U-PVC CATALOGUE WWW.SIZABANTUPIPINGSYSTEMS.COM

M-PVC & U-PVC - 2 Table Table of Contents of Contents PVC Pressure Pipe 3 Applications 3 Features and Benefits 3 SABS Specification 3 Dimensions of upvc Pressure Pipe 4 Dimensions of mpvc Pressure Pipe 4 Joining 6 Fittings for Pressure Pipe 7 PVC Fittings 7 SG Iron Fittings 9 Resilient Seal Gate Valves 15 Physical Properties 16 General 16 The Stress Regression Line 17 Design Stress and Safety Factor (service factor) 18 Effect of Temperature Change 18 The Effect of Ultra Violet Light 19 Chemical Resistance 19 Design Considerations 2 Pressure Considerations. 2 Temperature Considerations 23 Ultraviolet Light Considerations 23 Trench Load Considerations 24 Bending 29 Thrust Support 29 Flow Considerations 3

M-PVC & U-PVC - 3 PVC Pressure Pipe PVC (Polyvinyl Chloride) Applications upvc Pressure Pipe SABS 966 Part 1 and mpvc Pressure Pipes SABS 966 Part 2 may be specified with confidence for pumping mains and reticulation networks. upvc Pressure Pipe SABS 966 Part 1 They have, for many years, been successfully Applied in civil, effluent, purification, irrigation and industrial applications. mpvc Pressure Pipe SABS 966 Part 2 Features and Benefits Low mass Corrosion resistance Abrasion resistance Smooth bore Resilience Wavisafe Z-Lok@joint Ease of handling Reduced installation time Reduced transport costs Long, maintenance free, life span Excellent life span when pumping slurries Excellent flow characteristics Lower pumping costs Minimal handling damage Minimal installation damage Easy, effective, dependable joints SABS Specification upvc and mpvc pressure pipes are manufactured to, and carry the SABS Mark for SABS 966 Parts 1 and 2 respectively. Customers are therefore assured of consistently high quality pipes manufactured in an ISO 91 accredited factory with a design life of 5 years and a substantial safety factor at the end of that period.

M-PVC & U-PVC - 4 Dimensions of upvc Pressure Pipe SABS 966 Part 1-Pipe Dimensions Design Stress: 2mm-9mm sizes - 1 MPa 11mm - 5mm sizes -12.5 MPa All Sizes of Class 4-1 MPa Minimum wall thickness and Mass per 6 metre length Outside Diameter Class 4 Class 6 Class 9 Class 12 Class 16 Class 2 Class 25 Working Pressure 4kPa Working Pressure 6kPa Working Pressure 9kPa Working Pressure 12kPa Working Pressure 16kPa Working Pressure 2kPa Working Pressure 25kPa mm kg mm kg mm kg mm kg mm kg mm kg mm kg 2 1.5.79 1.9 1.1 25 1.5 1.1 1.9 1.25 2.3 1.53 32 1.5 1.31 1.6 1.55 2.4 2.3 2.9 2.46 4 1.5 1.65 1.8 1.96 2.3 2.47 3. 3.16 3.7 3.94 5 1.5 2.6 1.6 2.48 2.2 3. 2.8 3.77 3.7 4.88 4.6 6.12 63 1.5 2.63 1.9 3.31 2.7 4.64 3.6 6.9 4.7 7.8 5.8 9.73 75 1.5 3.15 2.2 4.57 3.2 6.56 4.3 8.67 5.6 11.7 6.9 13.78 9 1.6 4.53 2.7 6.73 3.9 9.56 5.1 12.34 6.7 15.69 8.2 19.67 11 2.2 6.77 2.6 8.14 3.9 12.11 5.1 15.67 6.7 2.29 8.2 24.46 1. 29.33 125 2.5 8.91 3. 1.66 4.4 15.53 5.8 2.25 7.6 26.15 9.3 31.55 11.4 37.87 14 2.8 11.19 3.3 13.19 4.9 19.37 6.5 25.41 8.5 32.75 1.4 39.51 12.8 47.73 16 3.2 14.64 3.6 17.36 5.6 25.32 7.4 33.1 9.7 42.76 11.9 51.73 14.6 62.31 3.9 22.4 4.7 26.92 7. 39.68 9.2 51.62 12.1 66.92 14.9 81.24 18.2 97.46 25 49. 35.33 5.9 42.46 8.7 62.66 11.5 81.12 15.1 15.3 18.6 127.58 22.8 153.55 315 6.2 56.44 7.4 67.28 11. 99.4 14.5 129.29 19. 167.12 355 7. 72.19 8.4 86.55 12.4 126.57 16.3 164.83 21.4 213.49 4 7.9 9.9 9.4 19.4 14. 161.41 18.4 21.21 24.1 271.22 45 8.9 115.2 1.6 139.39 15.7 24.6 2.7 266.65 5 9.6 14.97 11.6 172.59 17.4 252.34 22.9 327.84

M-PVC & U-PVC - 5 Dimensions of mpvc Pressure Pipe SABS 966 Part 2 - Pipe Dimensions Design Stress: 18 MPa Minimum wall thickness and Mass per 6 metre length Outside Diameter Class 6 Class 9 Class 12 Class 16 Class 2 Class 25 Working Pressure 6kPa Working Pressure 9kPa Working Pressure 12kPa Working Pressure 16kPa Working Pressure 2kPa Working Pressure 25kPa mm kg mm kg mm kg mm kg mm kg mm kg 5 1.5 2.1 1.5 2.1 1.7 2.4 2.2 3. 2.7 3.7 3.3 4.4 63 1.5 2.7 1.6 2.8 2.1 3.7 2.7 4.7 3.4 6. 4.1 7. 75 1.5 3.2 1.9 4. 2.5 5.3 3.2 6.8 4. 8.2 4.9 1. 9 1.8 4.6 2.2 5.6 3. 7.6 3.9 9.7 4.8 11.9 5.9 14.4 11 2.2 6.9 2.7 8.4 3.6 11.1 4.7 14.4 5.8 17.6 7.2 21.5 125 2.5 8.9 3.1 11. 4.1 14.4 5.4 19.1 6.6 22.7 8.2 27.9 14 2.8 11.2 3.5 14.2 4.6 18.1 6. 24.1 7.4 28.6 9.1 35.8 16 3.2 14.6 4. 18.2 5.2 23.5 6.9 3.8 8.5 37.6 1.4 45.5 2 3.9 22.3 4.9 27.9 6.5 36.8 8.6 48.2 1.6 6.3 13. 71,3 25 4.9 35.1 6.1 44.9 8.1 57.6 1.7 75.4 13.2 94.6 16.3 112.5 315 6.2 56.3 7.7 69.7 1.2 91.7 13.5 12.3 16.6 146.7 355 7. 72. 8.7 89.2 11.5 117.3 15.2 153.6 18.7 187.2 4 7.8 9.3 9.8 113.5 13. 149.8 17.1 195.4 21.1 238.59 45 8.9 116.7 11. 144. 14.6 19.1 19.2 247.35 23.7 32.13 5 9.8 144.4 12.2 177.7 16.2 234.8 21.3 35.46 26.4 347.57

M-PVC & U-PVC - 6 The seal ring s ribbed profile reduces friction during assembly. Joining The joint is integrally moulded on one end of the pipe. The joint incorporates a factory fitted rubber sealing ring which is retained in position by a polypropylene lock ring. Each joint is capable of handling some expansion and contraction as well as angular deflection. The seal ring is designed to provide a watertight joint at high and low pressures. Each length of pipe has a "depth of entry" mark on the spigot end to ensure correct installation. Rubber seal, firmly fixed into the correct position with a polypropylene lock ring. This prevents accidental displacement of the seal ring during jointing. Factory assembly ensures that the supplied joint is fully functional. No more concern about joint failure due to the use of randomly sized or incorrectly placed seals.

M-PVC & U-PVC - 7 Fittings for Pressure Pipe A wide range of complimentary fittings is available for use with pressure pipes. For sizes up to 25mm diameter, there are PVC bends, sockets and adaptors as well as a wide variety of SG Iron fittings. Larger sizes can be catered for from a selection of plain ended fabricated steel fittings in conjunction with Viking Johnson couplings. PVC Fittings PVC Bends All bends are made to suit either Class 9 or Class 16 applications and are available in 11¼, 22½, 45 and 9 angles. Outside Diameter A Overall Length B Radius C Mass (kg) 5 82 175.75 63 9 22 1.32 75 97 26 2.2 9 185 315 3.22 11 12 385 5.4 125 133 44 7.65 14 1435 49 1.33 16 161 56 15.8 2 192 7 27.82 25 222 875 5.23 9 Pressure Bend Outside Diameter A Overall Length B Radius C Mass (kg) 5 82 175.75 63 9 22 1.32 15 97 26 2.2 9 185 315 3.22 11 12 385 5.4 125 133 44 7.65 14 1435 49 1.33 16 161 56 15.8 2 192 7 27.82 25 222 875 5.23 45 Pressure Bend

M-PVC & U-PVC - 8 Outside Diameter A Overall Length B Radius C Mass (kg) 5 64 175.59 63 67 22.98 75 7 26 1.45 9 755 315 2.25 11 8 385 3.6 125 67 44 5. 14 92 49 6.62 16 125 56 9.6 2 119 7 17.24 25 135 875 29.53 22½ Pressure Bend Outside Diameter A Overall Length B Radius C Mass (kg) 5 64 175.59 63 67 22.98 75 7 26 1.45 9 755 315 2.25 11 8 385 3.6 125 67 44 5. 14 92 49 6.62 16 125 56 9.6 2 119 7 17.24 25 135 875 29.53 11¼ Pressure Bend Adaptors PVC AC The table below lists the available adaptors. PVC Outside Diameter A AC Pipe Nominal Size AC Pipe Actual outside diameter C 5 5 69 63 5 69 75 75 96 9 75 96 11 1 122 125 125 15 14 125 15 16 15 177 2 2 232 25 25 286

M-PVC & U-PVC - 9 PVC Double Sockets Double Sockets are used to connect plain ended pipes. There are sometimes short lengths of plain ended pipes required before or after fittings, such as tees, bends, etc. In these cases the most economical method of connection is to use a double socket. The table below lists the available sizes. Size Length 5 3 63 3 75 3 9 33 11 33 125 38 14 45 16 45 2 54 25 615 SG Iron Fittings SG Iron Equal Tees Nominal Size C D Mass (kg) 5 124 132 2.4 63 145 15 3.3 75 15 151 4.3 9 161 175 5.4 11 177 192 6.5 125 25 25 18.1 14 227 229 22.5 16 229 23 13.2 2 265 259 24.8 25 318 315 44.2

M-PVC & U-PVC - 1 SG Iron Hydrant Tees Nominal Size C D Mass (kg) 75 15 155 6.1 9 163 16 7.2 11 175 17 8.3 16 193 225 13.8 2 214 217 19.2 25 251 243 27.6 Table of available drilling patterns for SG Iron Hydrant Tees Specifications PCD No. of Holes Diameter of Hole 3 1/2 Table C BS1 165.1 4 18. 3 Table D BS1 146. 4 18. 8mm Table 1 SABS 1123 8mm Table 16 SABS 1123 16. 8 18. 16. 8 18. SG Iron Scour Tees Nominal Diamter C D Mass (kg) 11 18 175 9.8 16 27 197 14.1 2 218 23 21.1 25 254 253 34.2 Table of available drilling patterns for SG Iron Scour Tees Specifications PCD No. of Holes Diameter of Hole 4 Table D BS1 177.8 4 18. 1mm Table 1 SABS 1123 1mm Table 16 SABS 1123 18. 8 18. 18. 8 18.

M-PVC & U-PVC - 11 SG Iron Reducing Tees A full range of reducing tees from 63mm - 25mm is available in SG iron. Certain sizes consist of two components, eg. A 16mm x 5mm reducing tee is made up of a16mm x 9mm reducing tee plus a 9mm x 5mm reducer which fits into the branch of the reducing tee as shown in the diagram. The '*' denotes two part reducing tees in the table below. Nominal Size C D Mass (kg) 63x5* 13 16 4.3 75x5 15 152 4. 75x63 15 152 4.3 9x5* 154 189 6. 9x63 154 152 5. 9x75 159 158 5.5 11x5* 176 21 7.8 11x63 176 173 6.8 11x75 176 175 6.6 11x9 166 181 7.1 125x5* 25 335 24.7 125x63* 25 298 25. 125x75* 25 293 25. 125x9* 25 315 25.4 125x11* 25 264 22.7 14x5* 227 32 3.1 14x63* 227 283 3.4 14x75* 227 278 3.4 14x9* 227 3 3.4 14x11* 227 249 28.1 14x125* 227 25 26.1 16x5* 18 23 1.9 16x63 18 193 9.9 16x75* 18 255 13.3 16x9 193 212 11.4 16x11 24 216 11.2 16x125* 24 294 23.2 16x14* 24 272 22.2 2x5* 242 31 19.9 2x63* 242 264 2.2 2x75* 242 259 2.2 2x9* 242 281 2.3 2x11 242 23 17.9 2x125* 25 288 31.8 2x14* 25 266 31.8 2x16 25 253 21.6 25x5* 253 516 4.1 25x63* 253 417 4.4 25x75* 253 472 4.4 25x9* 253 494 4.5 25x11* 253 443 38.3 25x125* 253 443 83. 25x14* 253 421 48.5 25x16* 253 48 43. 25x2 253 295 3.8

M-PVC & U-PVC - 12 SG Iron Reducers There are two types of reducers available, namely socketed both sides and spigot and socket. Both are used for in-line reduction of pipe size. However, the spigot /socket reducer has an advantage when used in conjunction with a fitting. The spigot end can be fitted into any of the sockets on these fittings. Female reducers (socketed both sides) Nominal Size C Mass (kg) 75x63 222 2.4 9x63 224 3.1 9x15 25 3.5 11x63 27 8. 11x75 27 4.4 11x9 226 4.3 16x9 334 8.3 16x11 334 8.1 2x11 339 12.9 2x16 336 12.8 25x16 338 17.3 25x2 44 18.8 Male/Female reducer (spigot and socket) Nominal Size C D Mass (kg) 63x5(B) 137 1 1. 75x5(B) 141 16 1.1 75x63(B) 141 16 1.2 9x5(B) 144 112 3. 9x63(B) 144 112 1.7 9x75(B) 155 112 1.9 11x5(L) 255 12 2. 11x63(L) 156 122 2.3 11x75(B) 151 122 2.3 11x9(B) 113 122 2.4 125x11(B) 181 128 4.6 14x11(B) 15 13 5.6 14x125(B) 151 13 4.2 16x9(L) 31 141 4.8 16x11(B) 115 14 5. 16x125(B) 115 14 1. 16x14(B) 153 14 9. 2x11(L) 345 155 1.3 2x16(B) 215 155 7.5 25x16(L) 395 179 12.2 25x2(B) 218 179 12.8

M-PVC & U-PVC - 13 SG Iron Flange Adaptors Nominal Size C D E T Mass (kg) 5 15 15 47 19 2.2 63 135 165 55 19 2.8 75 124 2 7 19 3.4 9 155 2 8 2 4.3 11 158 22 9 2 4.7 125 16 255 11 22 14. 14 154 255 13 22 14. 16 185 28 14 22 9.1 2 177 34 18 25 14.8 25 21 45 23 28 23.8 Table of available drilling patterns for SG Iron Flange Adaptors Outside Diameter Flange Size Flange Size PCD BS 1 Table D SABS 1123 Table 1 SABS 1123 Table 16 No. of Holes Diameter of Holes PCD No. of Holes Diameter of Holes PCD No. of Holes Diameter of Holes 5+63 5 114.3 4 18 125 4 18 125 4 18 75 65 127. 4 18 145 4 18 145 4 18 11 1 177.8 4 18 18 8 18 18 8 18 125 125 29.6 8 18 21 8 18 21 8 18 14 125 29.6 8 18 24 8 22 24 8 18 16 15 235. 8 18 24 8 22 24 8 22 2 2 292. 8 18 295 8 22 295 12 22 25 25 355.6 8 22 35 12 22 355 12 26 SG Iron End Caps Nominal Size C Mass (kg) 5 117.9 63 121 1.5 75 128 1.8 9 129 2.5 11 135 2.7 16 154 5.7 2 228 8.6

M-PVC & U-PVC - 14 SG Iron Saddles Saddles are manufactured from SG iron, have four galvanised bolts and nuts, two straps and a rubber gasket which seats in a recess under the saddle. The standard drilling and tapping is 25mm BSP. Tappings up to 4mm BSP can be ordered. Nominal Size C D Mass (kg) 63 76 133 1.6 75 76 142 1.6 9 76 16 1.7 11 76 18 2. 16 76 23 2.4 2 76 27 2.8 SG Iron Repair Couplings These sleeve couplings are used for repairing breaks in pipelines. Nominal Size C 63 22 75 232 9 25 11 272 16 32 2 345 25 438

M-PVC & U-PVC - 15 Resilient Seal Gate Valves For waterworks purposes, double-socketed, nonrising spindle, Class 16. Materials Body and bonnet Coating* Stem Ductile iron, GGG-5, to DIN 1693 (BS 2789 grade 5-7) Electrostatically applied epoxy resin to DIN 3677 - internally and externally Stainless steel, DIN X 2 Cr 13 Stem sealing NBR wiper ring, 2 NBR O- rings inside and 2 outside a plastic bearing, EPDM rubber manchette Wedge Trust collar Bonnet bolts Bonnet gasket Sockets Ductile iron, GGG-5, core fully vulcanised with intergral wedge nut of dezincification resistant brass, CZ 132 to BS 2874 Dezincification resistant brass, CZ 132 to BS 2874 Stainless steel A2, sealed with hot melt EPDM rubber Fitted with EPDM rubber Euro sealing rings to suit metric PVC-pipes (to be ordered separately) *Also available internally enammeled DN Pipe Diameter External A L H F C E Mass (Kg) 4 5 13 27 236 14 64 44 7 5 63 13 286 241 14 8 52 8 65 75 18 298 271 17 82 58 9 8 9 115 315 297 17 85 68 13 1 11 125 12 5 15 16 2 2 2 22 5 25 25 25 28 3 31 5 4 4 118 336 334 19 1 79 18 115 348 375 19 118 87 24 13 4 448 19 14 17 4 135 426 562 24 156 13 56 151 452 562 24 15 142 58 161 474 664 27 152 157 8 166 54 664 27 172 174 95 172 548 74 27 24 193 123 185 596 95 32 226 24 246

M-PVC & U-PVC - 16 Physical Properties Polyvinyl Chloride (PVC) is a thermoplastic material which consists of a PVC resin compounded with varying proportions of stabilizers, lubricants, fillers, pigments, plasticizers and processing aids. Different formulations of these ingredients are used to obtain specific properties for different applications. Pipes can therefore be developed to meet the requirements of a wide variety of applications and conditions. General The general properties given in the table below are those for PVC compound formulations used in pipe manufacture. It should be noted that these properties are relative to temperature and the duration of stress application. Physical Units Value Coefficient of linear expansion K-1 6 1-5 Density kg/m2 1.4 13 Flammability (oxygenindex) % 45 Shore hardness 8 Softening point (Vicat - minimum) C 76 Specific heat J/kg/K 1. 13 Thermal conductivity (at - 5 C) W/m/K.14 Mechanical Elastic Modulus (longterm - 5 years) MPa 28 Elastic Modulus (short term - 1 seconds) MPa 14 Elongation at break % 75 Poisson s Ratio.4 Tensile strength (5 year - extrapolated) MPa 26 Tensile strength (minimum) MPa 48 Friction Factors Manning.8 -.9 Hazen Williams 15 Nikuradse roughness (k) mm.3 -.15

M-PVC & U-PVC - 17 The Stress Regression Line The traditional method of portraying the primary mechanical property of PVC, tensile strength, is by 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 2 C and 6 C, over a range of times up to 1, hours, are plotted on a log scale and a regression line is calculated to fit this data. The resultant regression line is then extrapolated to 5 years (438, hours). The method of calculation is an internationally accepted procedure described in ISO/TR 98. The required values of stress and time are specified in SABS 966 Parts 1 and 2. The internationally accepted method for calculating circumferential hoop stress is derived from Barlow's formula and is as follows: σ = p(d -t)/2t Where σ = hoop stress in wall of pipe (MPa) p = internal pressure (MPa) d = mean external diameter t = minimum wall thickness

M-PVC & U-PVC - 18 Design Stress and Safety Factor (service factor) Effect of Temperature Change Safety factors take into account handling conditions, service conditions and other circumstances not directly considered in the design. In terms of SABS 966 the following safety factors have been adopted. These factors have resulted in the given design stresses being applicable. The design stress is derived by dividing the 5 year hoop stress (26 MPa - from the stress regression line ) by the factor. Sizes 9 mm upvc Sizes 11 mm chosen safety mpvc All Sizes Working Pressure The standard design temperature for PVC pipes is 2 C and working pressures are usually quoted for this temperature. PVC pressure pipes function perfectly well below 2 C, right down to freezing point, and can in fact withstand higher pressures than those quoted at 2 C. As can be seen from the stress regression lines, the creep rupture strength diminishes with increasing temperature and working pressures must be down-rated if the same factors of safety are to be maintained. The applicable reduction factors are given under "Temperature Considerations" later. Safety Factor 2.5 2. 1.4 Design Stress (Mpa) 1. 12.5 18. Applying Barlow's formula (below) it is now possible to calculate the minimum wall thickness for any given size and pressure class of pipe. Expansion and Contraction All plastics have high coefficients of expansion and contraction, several times that of metals. This must be allowed for in any installation by the use of expansion joints, expansion loops etc. t = p d / (2σ + p) Material Co-efficient of expansion (K-1) PVC 8 1-5 Where: t = minimum wall thickness p = pressure (MPa) d = mean external diameter σ = design stress (MPa) For example the minimum wall thickness for a 25 mm Class 16 upvc pipe is: HDPE 2 1-5 Steel 1.2 1-5 Copper 2. 1-5 Sub Zero Temperatures Water has been known to freeze in PVC pipes without causing fractures, but permanent strain can result, leading to severe reduction in the working life of the pipe. Hence PVC pipes - like other pipes - should be protected against sub zero temperatures. t = 1.6 x 25 /{(2x 12.5)+ 1.6} =15.4 mm (rounded up to 15.1 mm for manufacture)

M-PVC & U-PVC - 19 The Effect of Ultra Violet Light Most plastics are affected by UV light. PVC pressure pipes have UV light stabilisers incorporated in their formulation but if pressure pipes have to be exposed for an indefinite period, they should be painted, preferably with one coat of white Alkyd Enamel or PVA. Long-term exposure (more than 4 to 6 months - dependant on climatic conditions) to UV light can cause discolouration of the pigments in the pipe and, in severe cases, lead to some embrittlement. Such embrittlement affects the ability to withstand impacts but does not reduce pressure handling capabilities. Chemical Resistance PVC pipes and fittings are highly resistant to acids, sewage or the most aggressive soils. Alkalis have very little effect on PVC. The table below summarises this resistance but further information can be obtained by contacting our technical department. Chemical Type PVC Reaction/Suitability Acids Alkalis Aromatic hydrocarbons and highly polar organic materials such as ketones, esters, cyclic ethers, nitro-compounds and hydrocarbons. Aliphatic hydrocarbons Aliphatic alcohols Halogens - chlorine Halogens - chlorine Halogens - bromine Halogens - flourine Halogens - iodine Oxidizing agents No attack by concentrated or diluted acids at temperatures up to 6 C, except for oxidizing acids such as concentrated nitric which attacks PVC above 2OC. In stressed applications, design stress,at 2C, should be reduced by: from 2.5% for 1% sulphuric - to 27.5% for concentrated nitric. No attack at temperatures up to 6 C even by concentrated alkalis. However in stressed applications, design stress must be reduced significantly, e.g. by 4-5% for 1% sodium hydroxide. Not suitable. No effect. No attack at room temperature but design stress must be reduced by half. No attack if dry. Not suitable if moist Not suitable Not suitable Not suitable Little attack even by the strongest, such as concentrated potassium permanganate, but design stress must be reduced by 25%. Reducing agents No effect up to 6 C Detergents No attack

M-PVC & U-PVC - 2 Design Considerations In SABS 966 there are 7 different pressure classes. These classes inlude suitable safety factors and are intended as a guide to trouble free operation under average service conditions. There are however many factors which must be considered when determining the severity of service and the appropriate class of pipe. This section is provided as a guide to the designer in the light of his or her knowledge of the particular circumstances. Amongst the factors to be considered are: Operating pressure characteristics: Static conditions Dynamic conditions Water hammer Cyclic loads Temperature Effect on pressure Effect on dimensions Trench load conditions Soil loads Traffic loads Bending Thrust support Flow considerations Selection of pipe size and class Pressure Considerations. Static Pressure The hydrostatic pressure capacity of PVC pipe is related to a number of variables: The ratio between the outside diameter and the wall thickness (standard dimension ratio) The hydrostatic design stress of the PVC pipe being used (upvc or mpvc) The operating temperature The duration and variability of the stress applied by the internal hydrostatic pressure Although PVC pipe can withstand short-term hydrostatic pressures at levels substantially higher than the pressure rating, or class, (see "The stress Regression Line" and "Design Stress and Safety Factor" earlier) the duty of PVC pipe should always be based on the pipe's long-term strength at 2 C to ensure a design life of at least 5 years.

M-PVC & U-PVC - 21 As stated earlier, the relationship between the internal pressure, the diameter and wall thickness and the circumferential hoop stress in the pipe wall, is given by the Barlow Formula, which can also be expressed as follows. p = 2 x t x σ/d or alternatively PVC pipes are capable of handling accidental events, such as pressure surges due to a power cut. However, if repetitive surges are likely to exceed about 1, occurrences during a 5 year operating lifetime, which is equivalent to an average of one surge wave every four hours for the total life of the pipe, then fatigue is a possibility and a fatigue design should be carried out. For most water supply lines this frequency of surges never occurs. t = p x d/(2σ + p) Where: p = internal pressure (MPa) t = minimum wall thickness d = mean outside diameter q =circumferential hoop stress (MPa) If stress peaks in excess of the design stresses are present, fatigue proceeds more rapidly and failure can occur earlier. For this reason peak pressures should not be allowed to exceed maximum recommended working pressures. These formulae have been standardized for use in design, testing and research and are applicable at all levels of pressure and stress. For design purposes, p is taken as the maximum allowable working pressure and q, the maximum allowable hoop stress at 2 C. The design hoop stresses used in SABS 966 are as follows: Part 1 sizes up to 9mm 1 MPa other sizes 12.5 MPa Part 2 all sizes 18 MPa Dynamic Pressure The pressure classes of SABS 966 PVC pipes are based on constant internal pressures. PVC pipes are however capable of handling dynamic pressure events which exceed the values given by the classes but such occurrences can have a negative effect on the normal 5 year life expectancy, and in extreme cases can result in product failure. Studies of fatigue response have shown that a fatigue crack initiates from some dislocation in the material matrix, usually towards the inside surface of the pipe where stress levels are highest, and propagates or grows with each stress cycle at a rate dependent on the magnitude of the stress. Ultimately the crack will penetrate the pipe wall, extending from a few millimetres to a few centimetres long in the axial direction and will produce a leak. It is important to appreciate that the growth of a fatigue crack is primarily dependent on the stress cycle amplitude, i.e. the maximum pressure minus the minimum pressure. Therefore a pipe subjected to a pressure cycle of zero to half working pressure is as much in danger of fatigue as one subjected to a pressure cycle of half to full working pressure. Thus pipe fatigue failures occur just as frequently at high points in the system as at low points where the total pressure is greater.

M-PVC & U-PVC - 22 WWW.SIZABANTUPIPINGSYSTEMS.COM Water Hammer Pipelines may be subjected to short-term increase in pressure above the normal working pressure due to water hammer. Water hammer will occur in a pipeline when its equilibrium is disturbed by rapid changes in flow conditions. Examples of such conditions are; starting and stopping of pumps, rapid opening and closing of valves, pipe failures etc. A rapid change in the velocity Δv of water in the pipeline gives rise to a pressure increase Δp according to the formula: Cyclic Loads A design for fatigue must involve: 1. An estimate of the magnitude of pressure fluctuations likely to occur in the pipe line, i.e. the difference Δp between maximum and minimum pressures. 2. An estimate of the frequency, usually expressed as cycles per day, at which such fluctu ations will occur. 3. A statement of the required service life needed from the pipe. Δp=cΔv/g Where:c = wave celerity (metres per second) g = acceleration due to gravity The wave celerity for upvc and mpvc have been calculated and are given below. Class m/s. m/s. 6 263 249 9 325 27 12 378 312 16 439 363 2 495 47 25 559 458 1. Since part of the formula for calculating wave celerity incorporates the ratio between diameter and wall thickness (SDR), which is roughly constant for all sizes within a pressure class, the wave celerities are also constant for all sizes within a pressure class. 2. By way of comparison the wave celerity for steel pipes is about 3 times higher than for PVC (1 to 14 m/s). It is important to note that the pressure I crease due to water hammer in a particular class of pipe is a function of the change in velocity and it is therefore important (for this and other reasons) to keep pumping velocities in a pipeline within the conventional norm of 1 to 2 m/s. In general steps should be taken during design and operation to minimize the frequency and intensity of water hammer. However the total pressure may be permitted to reach a value 5% higher than the nominal pressure if the frequency can be described as "occasional". The design can be done on the basis of the established relationship between pressure amplitude and the number of cycles to failure. This relationship is represented graphically below. The pressure amplitude is defined as the maximum pressure, minus the minimum pressure experienced by the system, including all transients, both positive and negative.

M-PVC & U-PVC - 23 Example A sewer rising main with a static rise of 15 metres and a total pumping head of 5 metres is designed to service a population of 4 growing to 1, in 5 years. Throughput is 3 litres/head/day average and well capacity is 2, litres. Over the life of the scheme the average throughput is 21, litres/day. Assuming that half the well capacity is utilised, then the average switching rate will be 21 cycles/day. Assuming there is no significant water hammer, the dynamic range is 35 metres. According to the chart a Class. 6 pipe is satisfactory. Effect on Dimensions Due to the relatively high coefficient of expansion and contraction (given in "Expansion and contraction" earlier) it is necessary to make allowance for this in any design and installation which is exposed to wide variations of temperature. PVC pipes will expand or contract by.8mm per metre per C rise or fall in temperature. A 3 C temperature rise will therefore cause a 14.4mm expansion of a 6 metre pipe. Temperature Considerations Effect on Pressure The pressure classes of PVC pipes carrying the SABS 966 mark have been allocated on the basis of design at 2 C. Any pipes used in applications where operating temperatures exceed 25 C need to be de-rated to ensure that the 5 year design life, or the safety factor, is not adversely affected. The following pressure reduction factors should be applied. Temperature 3 C.9 35 C.8 4 C.7 45 C.6 5 C.5 55 C.4 6 C.3 Working pressure factor Ultraviolet Light Considerations The vast majority of PVC pressure pipes are intended for burial in trenches and they are therefore manufactured with relatively low levels of additives to protect them against the effects of ultraviolet light. Pipes which will be exposed indefinitely to UV light should be protected by painting with a coat of light coloured Alkyd Enamel or PVA. Paint containing solvent thinners should be avoided. It is recommended that pipes should be buried wherever possible. N.B. The maximum recommended working temperature is 6 C At lower temperatures, between 2 C and C, the pressure handling capability does increase but it is recommended that this be ignored. If water freezes inside a PVC pipe permanent strain (if not fracture) may occur, leading to a possible severe reduction in the working life of the pipe.

M-PVC & U-PVC - 24 Trench Load Considerations It has been well established by researchers over many years that, for flexible pipes, it is the interaction between the soil and the pipe which has to be considered more extensively than is the case for rigid pipes where the material strength of the pipe is the critical issue. The points discussed here are given as a guide only to aid design by the engineer. Soil and Traffic Loads The vertical load on a PVC pipe due to soil is a function of the trench width and depth, the unit weight and type of the soil and the pipe diameter and wall thickness. This loading must generally be corrected because of the fact that the soil is cohesive and the side fill reacts with the fill above the pipe. Furthermore flexible pipes deflect and shed load to the side fill. This vertical deflection is limited by lateral soil resistance. The resultant load is therefore less than that which column theory suggests. The Soil Loading graphs below show that, after initial rapid increases with increased depth, this rate of increase falls away to almost zero at depths of about 6 metres or more. Typical maximum values of soil loads (without live loads) are between 1 and 17 N/m (for sizes between 5 and 5mm), depending largely on soil type, modulus and pipe stiffness. As soil compaction is increased so the maximum soil load on the pipe reduces, assuming that backfilling procedures have been followed. As can be seen from the Deflection vs. Soil Load graph there is a straight line relationship between deflection and soil load for each size and class of pipe. Therefore if the soil load reaches a maximum then the deflection also has a maximum. These graphs include the maximum soil loads from the soil load graphs and shows the maximum deflection (for the conditions represented) of less than 1.8% - for a 5mm Class 6 pipe - even with a 6 kn live load. Large diameter pipes carry more load because of their greater surface area. Thicker pipes carry more soil load because it is more difficult to deflect since less load shedding occurs. The graphs below were based on calculations using values typical for reasonable backfill material which has been poorly compacted (soil modulus of 3 MPa) excluding and including a 6 kn live load. Trench widths of.4m,.6m,.7m and.8m were used for the following groups of pipe sizes: 5mm -16mm, 2mm - 315mm, 4mm and 5mm. Different soil cover over the pipes were used, varying from.9m to 1m. The method of calculation was provided by Professor David Stephenson of Witwatersrand University. We have shown graphs on the following pages for class 6 and class16 only but have available graphs for class 9 and class 12 which show very similar trends. The graphs represent mpvc pipes. Soil load at shallow depths increases dramatically when a 6kN live load is added. This effect is aggravated by poor compaction. However, from about 3 metres deep this effect becomes negligible.

M-PVC & U-PVC - 25 Soil Loading on PVC Class 6 (No live Load, Soil 16 14 12 1 8 6 4 2.9 1.2 1.5 2 4 6 8 1 Depth Of Cover-Metres 5mm Class 6 75mm Class 6 11mm Class 6 2mm Class 6 315mm Class 6 5mm Class 6 Soil Loading on PVC Class 16 (No Live Load, Soil Modulus: 3 MPa) 2 18 16 14 12 1 8 6 4 2.9 1.2 1.5 2 4 6 8 1 Depth Of Cover-Metres 5mm Class 16 75mm Class 16 11mm Class 16 2mm Class 16 315mm Class 16 5mm Class 16

M-PVC & U-PVC - 26 Soil Loading on PVC Class 6 (With 6 kn Load, Soil Modulus: 3 MPa) 16 14 12 1 8 6 4 2.9 1.2 1.5 2 4 6 8 1 Depth of Cover-Metres 5mm Class 6 75mm Class 6 11mm Class 6 2mm Class 6 315mm Class 6 5mm Class 6 Soil Loading on PVC Class 6 (With 6 kn Load, Soil Modulus: 3 MPa) 2 18 16 14 12 1 8 6 4 2.9 1.2 1.5 2 4 6 8 1 Depth of Cover-Metres 5mm Class 16 75mm Class 16 11mm Class 16 2mm Class 16 315mm Class 16 5mm Class 16

M-PVC & U-PVC - 27 Deflection vs Soil Load PVC Class 6 (No Live 1.8 1.6 1.4 1.2 1..8.6.4.2 2 4 6 8 1 12 14 16 18 Soil Load - N/m 5mm Class 6 75mm Class 6 11mm Class 6 2mm Class 6 315mm Class 6 5mm Class 6 Deflection vs Soil Load PVC Class 16 (No Live Load, Soil Modulus: 3 MPa) 1.4 1.2 1.8.6.4.2 2 4 6 8 1 12 14 16 18 2 Soil Load - N/m 5mm Class 16 75mm Class 16 11mm Class 16 2mm Class 16 315mm Class 16 5mm Class 16

M-PVC & U-PVC - 28 1.8 Deflection vs Soil Load PVC Class 6 (6 kn 1.6 1.4 1.2 1..8 2 4 6 8 1 12 14 16 Soil Load - N/m 5mm Class 6 75mm Class 6 11mm Class 6 2mm Class 6 315mm Class 6 5mm Class 6 Defection vs Soil Load PVC Class 16 (6 kn Live Load, Soil Modulus: 3 MPa) 1.6 1.4 1.2 1.8.6.4.2 2 4 6 8 1 12 14 16 18 2 Soil Load - N/m 5mm Class 16 75mm Class 16 11mm Class 16 2mm Class 16 315mm Class 16 5mm Class 16 Note: Calculations with a higher soil modulus (not shown), implying better compaction, show much lower deflection percentages and reduce the gap between the static soil load and the live load.

M-PVC & U-PVC - 29 Bending An important feature of PVC pipes is that they may be deliberately bent, within limits, thus eliminating the need, in some cases, for separate bends. As a rule of thumb the radius of such a bend must not be less than 3 times the pipe diameter. In addition each rubber ring joint can accommodate a further ½ of bend. This feature significantly reduces costs and speeds up installation times when co pared to some traditional pipe materials. Thrust Support An unbalanced thrust is developed by a pipeline at: Changes of direction greater than 1 e.g. Tees and Bends, Changes in pipeline size, Valves and Endcaps. When cover is less than 6mm it may be necessary to take further precautions to prevent vertical movement due to thrust. If the pipeline is to be pressure tested at a pressure higher than working pressure then thrust block design must allow for this pressure. The tables below along with the supplied example, provide a guide to determine thrust block sizes. Table of soil safe bearing loads. Table of approximate thrust on fittings for each 1m Material Peat, running sand, muck, ash etc Soft clay 5 Medium clay, sandy loam 1 Sand, gavel and hard clay 15 Sand and gravel, cemented with clay 2 Safe Bearing Load (kpa) Sand and gravel, cemented with rock 24 (1kPa) of pressure in the line. Pipe O.D. 9 Bend (k) Closed end (kn) Tee or 45 Bend (k) 22 1/2 Bend (kn) 11 1/4 Bend (kn) 5.27.19.15.8.4 63.43.31.23.12.6 75.61.43.33.17.8 9.88.62.48.24.12 11 1.32.93.71.36.18 In most cases the soil bearing capacity is insufficient to withstand such forces and it becomes necessary to use thrust blocks if the pipes have rubber ring joints. The size of the bearing area of the thrust blockis determined by the bearing capacity of the particular type of soil into which the pipe is installed and by the diameter and operating pressure of the pipeline. 125 1.7 1.2.92.47.24 14 2.13 1.51 1.16.59.3 16 2.79 1.97 1.51.77.39 2 4.36 3.8 2.36 1.2.6 25 6.81 4.81 3.68 1.88.94 315 1.81 7.64 5.85 2.98 1.5 355 13.72 9.7 7.43 3.79 1.9 4 17.42 12.32 9.43 4.81 2.42

M-PVC & U-PVC - 3 Example: Calculate the bearing area of a thrust block for a 2mm x 9 bend. Class of pipe 12 Maximum working pressure Test pressure 96mPa 12mPA Bearing soil Sand / gravel From the parameter table above the thrust equals: 4.36 x 12/1 = 52.36 kn The safe bearing load of sand/gravel = 15kPa The bearing area of the thrust block = 52.36/15 =.35m² The thrust block bearing surface dimensions should be.6m x.6m =.36m² Flow Considerations The tables that follow provide a guide to friction losses that can be expected when using clean upvc and mpvc pressure pipes with clean water at 2 C. Possible fittings in line was not taken into account. How to read these charts. Choose the particular chart for the type (upvc or mpvc) and class of pipe being used. In one of the first three columns find the nearest value of the quantity of water to be pumped according to the preferred unit of measurement. GPH = Gallons per hour m³/hr = Cubic meters per hour l/s = Litres per second Align the selected reading horizontally to the light green shaded values. The value in the shaded block is the friction loss for the size of pipe given at the top of that particular column. (Expressed in meters per 1 metres). The reverse sequence can be used to determine the amount of water that can be pumped through a given pipe size (and how much friction loss is created)

M-PVC & U-PVC - 31 Selection of Pipe Size and Class Nominal bore of SABS 966 Pipes Class 4 6 9 12 16 2 25 Working Pressure kpa 4 Test Pressure 1.25 * Pressure Class (SABS 12) kpa Outside Diameter 5 upvc mp VC 6 9 12 16 2 25 75 1125 15 2 25 3125 upvc mpvc upvc mpvc upvc mpvc upvc mpvc upvc mpvc upvc mpvc 16 13-13 - 13-13 - 13-13 - - - 2 17-17 - 17-17 - 17-16 - - - 25 22-22 - 22-22 - 21-2 - - - 32 3-29 - 29-28 - 27-25 - - - 4 38-37 - 36-35 - 34-32 - - - 5 48-46 47 45 47 44 46 42 45 4 44-43 63 6-59 6 57 6 55 58 53 57 51 56-54 75 71-7 72 68 71 66 7 63 68 6 66-65 9 85-84 86 82 85 79 84 76 82 72 79-78 11 - - 14 15 12 14 99 12 96 1 92 98 89 95 125 - - 119 12 116 118 113 116 19 114 14 111 11 18 14 - - 133 134 129 133 126 13 122 127 118 124 113 121 16 - - 152 153 148 151 144 149 139 145 134 142 129 138 2 - - 19 192 185 19 18 186 174 182 168 178 161 173 25 - - 237 24 231 237 225 233 218 227 21 222 21 216 315 - - 299 32 291 299 264 293 274 287-28 - - 355 - - 337 34 328 337 32 331 39 323-316 - - 4 - - 38 384 37 379 36 373 348 364-356 - - 45 - - 427 431 416 427 45 419-41 - 4 - - 5 - - 475 479 463 474 451 466-455 - 444 - -