Document X7yVQYZYyQLQVkXRBobo7M0ng

314 Chapter 16 1945 Guide or may be machined with concentric or spiral grooves often referred to as serrated face or phonograph finish, respectively. ' . .. . The dimensions of elbows, tees and crosses for 125 lb cast-iron screwed fittings are given in. Table 6,: whereas the dimensions, for 125 lb cast-iron ' flanged fittings are given in Table, 7. For low temperature service not to. exceed about 220 F, a number of paper or vegetable fiber gasket materials will prove satisfactory; for plain Table 5. American Standard. Dimensions of Elbows, Tees, Crosses, and 45 Deg Elbows, Soldered-Joint Fittings, A.S.A. A40.3-1941 Cast Brass1* Nonraii Size* - Laying .' Length. Tee, ED, and Cro68b Laying Length, EU With External Shoulder Laying Length, 45 Deg EU Laying Inside - Length, Diameter 45 Deg Ell of External Fittings,0- Shoulder Min. Metal Thickness11 Wrought ,, Metal Metal Thickness' Min.* Bore or Fittings H i J . Q 0 T R T and R . E, Min, A A .A . A A 0.31 0.08 0.048 0.030 0.378 Vs A. A A A 0.43 0.08 0.048 0.035 0.503 A A A . A A , 0.54 0.09 "0.054 0.040 0.628 A A % A A 0.78 0.10 0.060 0.045 0.878 l A A A A 1.02 0.11 0.066 0:050 1.1285 lA A l A A 1.26 0.12 0.072 0.055 1.3785 \a 1 l A A A 1.50 0.13 0.078 0.060 1.629 2 lA 1A 96 - A 1.98 0.15 0.090 0.070 2.129 1A 1A , A ' A 2.46 0.17 0.102 0.080 2.629 3 mm A1 2.94 0.19 0.114 0.090 3.129 &A 2 2A A l A . 3.42 0.20 0.120 0.100 3.629 4 2A 2A % 1A 3.90 0.22 0.132 0.110 4.129 5 m 1A 4.87 0.28 0.168 0.125 5.129 6 3% -- 1A 5.84 0.34 0.204 0.140 6.129 . All dimensions given in inches. "This size is the nominal bore of the tube. bThese dimensions may be used for wrought-metal fittings as well as for cast-brass fittings at maau' facturer's option. oThis dimension is the same as the inside diameter Class L tubing (American Standard Specifications for Copper Water Tube. Aji. H23.1-1939 B88). - dPatterns shall be designed to produce body thicknesses given in the table. Metal thickness at no point shall be less tha 90 per cent of the thicknesses given in the table. eTbis dimension has the same thickness as Type L tubing. fThese dimensions are minimum, but in every case the thickness of wrought fittings should be at least as heavy as the tubing with which it is to be used. Note 1:--Wrought fittings, as well as cast fittings, must -be provided with a shoulder or stop at the bottom end of socket. . Note 2:--Street fittings with male ends are for use in connection with other fittings illustrated. raised face flanges, rubber or rubber inserted gaskets are commonly employed. Asbestos composition gaskets are probably the most widely used, particularly where the temperature exceeds 250 F. Jacketed asbestos and metallic gaskets may be used for any pressure and tem perature conditions, but preferably only with a narrow recessed facing. ' ..-i- x Pipe, Fittings, Welding , ' ' .' ' ~ _________ 315 - 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 arid flanged fittings Table 6. American Standard'Dimensions of Elbows, 45-Deg Elbows, Tees, and Crosses (Straight Sizes) for Class 125 Cast Iron Screwed Fittings, A.S.A. B16a-1939 *-A-- j--/ _L Aj 1F- U AA Li-J j _L Elbow Tee Cross 45 deg elbow Nominal Pin Size A Center to End, Elbows, Tees and Crosses c. B B' Center to End, 45 Deo Elbows Length or Thread, Min. Width or Band. Min. F Inside Diameter or Pitting Min. Max. QH Metal Thickness,8 Mm. Outside Diameter or Band, Met A A H A l lA 2 2A 3 3H 4* 5 6 8 10 . 12 0,81 0.95 1.12 1.31 1.50 1.75 1.94 2.25 .2.70 3.08 3.42 3.79 4.50 5.13 6.56 8.08>> 9.506 ' 0.73 0.80 0.88 0.98 1.12 1.29 1.43 1.68 1.95 2.17 2.39 2.61 3.05 3.46 4.28 5.16 5.97 0.32 0.36 0.43 0.50 0.58 0.67 0.70 0.75 0.92 0.98 1.03 1.08 1.18 1.28 1.47 1.68 ' 1.88 0.38 0.44 0.50 0.56 0.62 0.69 0.75 0.84 0.94 1.00 1.06 1.12 1.18 1.28 1.47 1.68 1.88 0.540 0.675 0.840 1.050 1:315 1.660 1.900 2.375 2.875 3.500 4.000 4.500 5.563 6.625 8.625 10.750 12.750 0.584 0.719 0.897 1.107 1.385 1.730 1.970 2.445 2.975 3.600 4.100 4.600 5.663 6.725 8.725 10.850 12.850 0.110 0.120 0.130 0.155 0.170 0.185 0.200 0.220 0.240 0.260 0,280 0.310 0.380 0.430 0.550 0.690 0.800 0.93 1.12 1.34 1.63 1.95 2.39 2.68 3.28 3.86 4.62 5.20 5.79 7.05 8.28 10.63 13.12 15.47 All dimensions given in inches. `Patterns shall be designed to produce castings of metal thickness given in the table. ai no point shall, be iess than 90 per cent of the thickness given in the table. ^Applies to. elbows and tees only. Metal thickness is dependent on the individual job, the use of. welding is generally recom- ' mended on the basis of a greatly reduced cost of maintenance and repair, of less weight resulting from the use of a lighter-weight pipe, and of increased economy in pipe insulation, hangers, and supports rather than on the basis of any economy that might be effected in actual erection by welding ori 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 states, without the application of mechanical pressure or blows.' Fusion welding