GAIL (India) Limited

73a) All GI pipes fittings and valves of rising main from finished Ground level to over head tanks as indicatedin the drawings.b) All GI pipes with fittings and valves from over head tank to all taps, wash basins, cisterns, sinks.2. MATERIALS2.1. Galvanized Iron Pipes and Fittings:2.1.1. The pipes shall be galvanized mild steel tubes medium grade conforming to BIS 1239. All pipes shall beelectric resistance welded screwed with taper, threads and sockets with paralleled threads, Threads shallconform to BIS 554-1964 The pipes and sockets shall be clearly finished, well galvanized in and out andfree from cracks, surface flaws, laminations and other defects All screws threads shall be clean and wellcut The ends shall be cut cleanly and square with axis of the tube2.1.2. The fittings shall be malleable iron and comply with all the requirements that of pipes. The fittings shallbe designed by the respective nominal bores of the pipes for which they are intended,2.1.3 The standard weight and thickness of pipes shall be as shown in the following tables.Nominal of Boretubes mmClassWall thick- ness inmmNominal weightblack Tube kg/mNominal weightGalvanised kg/m15 M 2.65 1.22 1.274H 3.25 1.45 1.50420 M 2.65 1.58 1.642H 3.25 1.90 1.95325 M 3.25 2.44 2.525H 4.05 2.97 3. 0532 M 3.25 3.14 3.247H 4.05 3.84 3.93740 M 3.25 3.61 3.731H 4.05 4.43 4.545NOTE :M = Medium, H- Heavy3. CUTTING, LAYING AND JOINTING OF PIPES AND FITTINGS3.1 Where pipes have to be cut or re-threaded, ends, shall be carefully filed out so that no obstruction to boreis offered. The ends of the pipes shall then be threaded conforming to requirements of BIS 554-1964 withpipe dies and tapes carefully in such a manner as will into result in slackness of joints when two pieces arescrewed together. The pipe shall be clean and cleared of all foreign matters before being laid. All pipesand fittings shall be properly jointed to make the joints completely water tight and all pipes kept free fromdust during fixing. Burr shall be removed from the joints after screwing.3.2 All GI pipes below ground shall be laid in trenches and shall have a minimum cover of 600 mm, paintedwith two coats anticorrosive bitumastic paint, filling 150 mm thick sand all round the G.I. pipes.3.3 The runs of the pipe shall be truly vertical and horizontal. Proper bends, elbows, tees atturning/corners shall be used.3.4 All GI pipes with necessary fittings wherever they are laid on internal faces of the walls shall beconcealed in chase, sand painted with two coats of anticorrosive bitumastic paint. On external faces theywill be laid on walls fixed with GI clamps.3.5 In the concealed portion of the piping no joint shall be provided in the pipe lines except in the fittings i.e.bend, elbows, tees and nipples where required.