Document b58ka6g4azgDOq49ejxO324M0

HEATING VENTILATING AIR CONDITIONING GUIDE 1942 asbestos and metallic gaskets may be used for any pressure" and tem fpaecriantgu.re conditions, but preferably only with a relatively narrow recessed WtLDING Erection of piping in heating and ventilating installations by means of fusion welding has been commonly accepted in the past few years as a competitive method to the screwed and flanged joint. Since the question Table 8. American Standard Dimensions of Tees and Crosses1 (Straight Sizes) for Class 125 Cast-Iron Flanged Fittings, A.S.A. B 16a-1939 CHAPTER 18. PIPE, FITTINGS, WELDING 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 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 * *1___ TaAle 9. a.Givnun Dimensions of Elbows Class 125 NoXZXAb Pm Stkb b-c A Center to Facb Tees and Crosses e-d AA FaTceeetsoaFnace Crosses o-d Duhbtes or Flange ThiFclkannegses, or Mir. Metal* Thickness or Boot 1 ImK 2 2K 3 3K 4 5 6 8 10 12 14 O.D. 16 O.D. 18 O.D. 20 O.D. 24 O.D. 30 O.D. 36 O.D. 42 O.D. 48 O.D. m 3K 4 4K 5 5K 6 'm 7K 8 9 11 12 14 15 16K 18 22 25 28 31 34 7 m 8 9 10 11 12 13 15 16 18 22 24 28 30 33 36 44 50 56 62 68 4K 4He 5 6 7 m Wi 9 10 11 13H 16 19 21 23^ 25 27H 32 38% 46 53 5914 He K H6 K*8 ;k* `K* i% iK* mi K We IK* iJH* IK . 2K 2K 2K 2K He He He He He H He K K He He H \He 1% \ IK IK* IK 1 lHe 2 All dimensions given in inches ^Crosses both straight and reducing sizes 18 in. and larger shall be reinforced to compensate .for the inherent weakness in the casting design. bSize of ail fittings listed indicates nominal inside diameter of port. CTees, side outlet tees, and crosses. 16 in. and smaller, reducing on the outlet, have the same dimensions center to face, and face to face as straight size fittings corresponding .to the size of the larger opening. Sizes 18 in. and larger, reducing on the outlet, are made in two lengths, depending on the size of the outlet, dTees and crosses, reducing on run only, carry same dimensions center to face and face to face as a straight size fitting of the larger opening. eBody thickness at no point shall be less than 87K per cent of the dimensions given in the table. 354 All dimensions given in Inches. Size of all fittings listed indicates nominal inside diameter of port. ^Reducing elbows and side outlet elbows carry same dimensions center to face as straight size elbows corresponding to the size of the larger opening. eSpecial degree elbows, ranging from 1 to 45 deg. inclusive, have the same center to face dimensions as given for 45*deg elbows and those over 45 deg and up to 90 deg, inclusive, shall have the same center to face dimensions as given for 90-deg elbows. The angle designation of an elbow is its deflection from straight line flow and is the angle between the flange faces. aside outlet elbows shall Save all openings on intersecting center-lines. 355