Specifications Part 1 - Water Supply, Sewerage and Tube Well Works

Nominal Diameter Outer diameter of flange Holes Bolt sizeDN D Number Dia(d) Metric250 400 12 28 M24300 455 12 28 M24350 520 16 28 M24400 580 16 31 M27450 640 20 31 M27500 715 20 34 M30600 840 20 37 M33700 910 24 37 M33750 970 24 37 M33800 102 24 40 M36900 112 28 40 M361000 125 28 43 M394.3 Coating:Pipe shall be supplied internally (cement mortar lining) and externally(bituminous coating) coated as under:4.3.1 Cement Mortar Lining -4.3.1.1. Cement -the cement used for the lining shall conform to the existing standardson cement, The type of cement to be used is to be mutually decided betweenthe purchaser and manufacturer, Normal recommendations are:4.3.1.1.1 Portland cement (as per IS 8112 or IS 455) mortar lining perform rather welland have an expected life of approximately 50 years in soft water withmoderate amount of aggressive Co 2 and when Ph is within 6 to 9. Longerservice life can be obtained by increasing the mortar lining thickness.4.3.1.1.2 Where cement mortar lining may be exposed to sulphate attack, ordinaryPortland cement should be replaced by sulphate resisting Portland cement (asper IS 12330 or IS 6909).4.3.1.1.3 The sulphate concentration limit for sulphate resisting Portland inapproximately 3000 mg/liter, the same as blast furnace slag cement whichnaturally possess a good resistant to sulphate attack.4.3.1.1.3 High alumina cement (as per IS 6452) mortar lining is suitable for continuoususe of pH between 4 and 12 and no sever damage occur after occasionalexposure to pH 3 to 4 and 12 to 13.4.3.1.1.4 The recommended type of cement used for lining are as given in table 4.5Urban Administration & Development Department Page 44