ASME B16.1-2020 pdf download

ASME B16.1-2020 pdf download.Gray Iron Pipe Flanges and Flanged Fittings.
Pressure–temperature ratings are maximum allowable working pressures in bar (psi) units at the temperature in degrees Celsius (Fahrenheit) shown in Table 3.1-1 for the applicable material and class designation. For inter- mediate temperatures, linear interpolation is permitted. Interpolation between class designations is not permitted. 3.2 Flanged Joints A flanged joint is composed of independent interrelated components: the flanges, gasket, and bolting, which are assembled manually. Proper controls must be exercised in the selection and application for these elements to attain a joint that has acceptable leak tightness. Special techniques, such as controlled bolt tightening described in ASME PCC-1, may be used to achieve a tight joint in service.Gray iron has little ductility; therefore, the resistance of these flanges and flanged fittings to excessive forces and suddenly applied loads is significantly less than for more ductile materials, such as steel. The following precautions are recommended: (a) These flanges and flanged fittings should not be used where suddenly applied loads such as rapid pressure fluctuation may occur. (b) Alignment of flange faces is essential along with control of assembly bolt torque so as not to over- stress the gray iron flanges. Care should also be exercised to ensure that piping loads transmitted to gray iron flanges are controlled.
The center-to-face dimensions for straight-size tees and crosses, with or without side outlet, and laterals are shown in Tables 7.3.2-1 through 7.3.2-3. (b) Reducing tees and reducing crosses, with or without side outlet, and reducing laterals, NPS 16 and smaller, shall have the same center-to-face dimensions as straight-size fittings shown in Tables 7.3.2-1 through 7.3.2-3 corresponding to the size of the largest opening. For NPS 18 and larger, if the outlet of a reducing tee; the branch of a reducing lateral; or the largest outlet of a reducing side outlet tee, reducing cross, and reducing side outlet cross is the same size or smaller than given in Tables 7.3.2-1 through 7.3.2-3 (short-body pattern), the center-to-face dimensions shown in these Tables shall be used. If a branch or any outlet is larger than shown in Tables 7.3.2-1 through 7.3.2-3, the center-to- face dimensions shall be the same as for the straight- size fitting shown in Tables 7.3.2-1 through 7.3.2-3 corre- sponding to the size of the largest opening. Tees, crosses, and laterals, reducing on the run only, shall have the same center-to-face dimensions as straight-size fittings shown in Tables 7.3.2-1 through 7.3.2-3 corresponding to the size of the largest opening. (c) Tees reducing on both runs are generally known as bull-head tees and have the same center-to-face dimen- sions as straight-size fittings corresponding to the size of the outlet. 7.3.4 True Y’s . Center-to-face dimensions for straight- size true Y’s are shown in Tables 7.3.2-2 and 7.3.2-3. Re- ducing sizes are considered special and should be made to suit conditions. 7.3.5 Reducers and Eccentric Reducers. The face-to- face dimensions for all reductions of reducers and eccentric reducers shall be the same as given in Tables 7.3.2-2 and 7.3.2-3 for the largest opening.
It is recognized that some variations are absolutely unavoidable in the making of patterns and castings. Equip- ment shall be designed to produce wall thicknesses given in the tables. Wall thickness at no point shall be less than 87.5% of the thickness given in the tables. 7.2 Facing (a) Classes 25 and 125 gray iron flanges and flanged fittings shall be flat faced (i.e., without projection or raised face) and finished in accordance with MSS SP-6. (b) Class 250 flanges and flanged fittings shall have a 2 mm (0.06 in.) raised face of the diameters given in Table 7.6.1-3 and finished in accordance with MSS SP-6. The raised face is included in the minimum flange thickness and center-to-face dimension. 7.3 Center-to-Face Dimensions 7.3.1 Side Outlet Fittings. Side outlet elbows, side outlet tees, and side outlet crosses shall have all openings on intersecting centerlines. Long-radius elbows with side outlet shall have the side outlet on the radial centerline of the elbow. 7.3.2 Elbows (a) The center-to-face dimensions for straight-size 90- deg elbows, 90-deg long-radius elbows, 45-deg elbows, side-outlet 90-deg elbows, and double-branch elbows are shown in Tables 7.3.2-1 through 7.3.2-5.