Document LpwNQ5nxRKBMKkaJEdQ59Rk23

684 CHAPTER 26 1957 Guide. WELDING Erection of piping in heating and ventilating installations by means of fusion welding has been commonly accepted in the past few years as an alternate method to the screwed and flanged joint.. Since the question of economy of welding as against the use of screwed and flanged fittings is dependent on the individual job, the use of welding is generally recom mended on the basis of: greatly reduced cost of maintenance and repair; Table 17. Dimensions op Cast Brass Solder-Joint Couplings (Straight, Reducing and Eccentric Sizes) COUPLING C TO C REDUCING COUPLING ECCENTRIC COUPLING C TO C STRAIGHT REDUCING ECCENTRIC Size H H M s l 1H 1H 2 2M i 3K 4 5 6 8 Length* M . Me Me H K :H K H k. H H H K H Standard Water Tube Size Hz M 1 xH lMxl IK i H lMz 1M lHxl 1. X 2 x 1M 2 z 1H 2 x1 2 xH 2Mx2 2HxlH 2Hx m 2H x 1 3 x2H 3 x2 4 x3 4 x2H 4 x2 6 x4 8 x6 ' Latino Length* N He H H H H H K. K K K K H % H H H Ho m IHe IHe 1H Standard Wateb Tube Size i k l xH 1H x 1 lMx H IK x IK mil 2 X 1M 2 x 1H 2Mx2 3 x2M 3 x2 4 x3 Latino Length* W H *Me H H *Me 1H *Me IHe 1H IHe 2 From American Standard for Cast-Brass Solder-Joint Fittings, ASA B16.18-1950. All diTM>ngtnM given in inches. * Not standardised for wrought fittings. Consult manufacturer for dimensions. reduced weight resulting from the use of a lighter-weight pipe; or increased economy in pipe insulation, hangers, and supports rather than any econ-. omy that might be effected in actual erection by welding on low to medium pressure heating jobs. Fusion welding, commonly used in erection of piping, is defined as the process of joining metal parts in the molten, or molten and vapor stateSi without the application of mechanical pressure or blows. Fusion welding embraces gas welding and electric arc welding, both of which are commonly Pipe, Fittings, Welding 685 Table 18. Dimensions op Flanged Cast-Iron and Steel Valves Angle Contact Surface to Contact Surface Dimensions, (2 X AA) Nominal Pipe Size Capt-Ibon 800` 125 1751' * 250> Hy 1501 3001 draulic Steel 4001 G001 900' 15001 s < < O B e -& 1 JH 1M - 2 2M 3 3)4 4 5 6 10 12 14 OD 16 OD IS OD 20 OD 24 OD 8)4 8K 10 9 9 n 7K 9)4 9K 12 10 11 12 7 7K 8K UK 7)4 8 9K 13 8 9M 11H 14 8)4 10 11)4 9 10)4 12 17 7 8K 11)4 llH 14)4 14)4 7K 9K 13 13 16)4 16)4 8 11H 14 14 15 18)4 8M 11)4 9 12 16 17 18 21M 10 UK 15 10)4 13 15)4 22 11M 14)4 16)4 26 13 16H 18 3i 14 17K 16H 33 10 10)4 UK 13 14 15 18 15)4 19)4 16)4 23K 18 * 28)4 19H 30 20 22 26 31 33 22 26M 24 27H 29 32H 33 39 38 44K 15 22)4 15 30 32)4 35 40)4 16 17 24 26 16 33 17 36 35)4 39 38)4 43 44K 48 18 28 18 39 41)4 : 47 52 20 31 20 45 48)4 55 . 61 K H 1M > 1H 7K 7K 8K SK 10 9 9 11 9K 9K 12 10 11 12 .3 0 2 z 2M 3 . 2)4 aa 8 8)4 9K 10)4 UK 10)4 UK 12)4 13 M 14 8 10)4 8K 11)4 9K 12)4 10)4 13)4 UK 14 UK 11)4 13 13 14 14 io i7 14)4 14H 16)4 16H 15 18M 18 21M 5 -- 13 14 19H 15K 17K 21 14 15H 16 17K 19M 22 18 20 19)4 22 23)4 26 22 26M 24 27H 29 32H Bl6^H39mei'Can tan^ar^ for Face-to-Face Dimensions of Ferrous Flanged and Welding End Valvee, ASA All dimensions given in inghew. dimensions are not given, the sizes either are not made or there is insufficient demand to warrant the pense of unification. a?d groove joint facings have bottom of groove in same plane as fianoe edge, and center to cont dimensions for these facings are reduced by the amount of the raised face, end flange**TM presaure designations which refer to the primary service ratings in lb per sq in. of the connecting * connec^ng end flanges of 175 lb valves are the same as those on 250 lb valves, and to contact surface dimensions and connecting end flanges for 400 lb valves 3 in. size coDn^Ktr1'' identical with thoee of 600 lb valves; and the contact surface to contact surface dimensions and * e&d flanges for 600 lb valves 2H in. size and smaller, are identical with those of 1500 lb valves.