ASME B73.1:2012 pdf download.Specification for Horizontal End Suction Centrifugal Pumps for chemical Process.
5.2 Flanges
5.2.1 General. Suction and discharge nozzles shall be flanged. Flange drilling. Lacing, and minimum thickness shall conform to ASME B16.5 Class 150 or ASME 816.42 Class ISO standards, except that marking requirements are not applicable and the maximum acceptable tolerance on parallelism of the back of the flange shall be 3 deg. Flanges shall be flat-faced at the full raised-face thickness (minimum) called (or in the ASME standards for the material of construction. Raised-face flanges may be offered as an option. Bolt holes shall straddle the horizontal and vertical centerlines. Bolt holes may be tapped when adequate space for nuts is not avaibble behind flanges. as noted in Table 1.1. Through bolt holes are preferred. When tapped holes are supplied, they shall be noted on the outline drawing.
5.2.2 Class 300 Option. As an option, Class 3(x) flanges in accordance with ASME 8165 or ASME 616.42 may be offered with prtssure ratings subixt to the manulacturer s casing pressure—lemperature limitations. Class 300 t1anges shall be flat-faced at full raised-lace thickness (minimum), or raised-face flanges may be offered as an option.
5.2.3 X and V Dimensions. All pumps. n!gardless of flange rating, shall conform to the X and Y dimensions shown in Table 1.1.
5.2.4 Heavy Hex Nuts. When heavy hex nuts cannot be used, the location shall be noted on the outline drawing.
NOTE: ASME B16.3 and ASME B16.42 indIcate the use o heavy hex nuts lur certain 1l.mge connLvlions. On mans B73 pumps, heavy Iws nuts rannot be used due to available space Standard hex nuts are often subsqltuqed. The use o standard hex nuts may not allow the achievement of full bob ietess, which may Impact proper gasket conpfrion. With most gasler materials, this does not reduce the gasket’s abIlity to properly seal, However, this a coiwideratlon for metallic and semimetallir gaskets where slgrnflcant preload may be required to achieve stalfident tightness.
5.2.1 General. Suction and discharge nozzles shall be flanged. Flange drilling. Lacing, and minimum thickness shall conform to ASME B16.5 Class 150 or ASME 816.42 Class ISO standards, except that marking requirements are not applicable and the maximum acceptable tolerance on parallelism of the back of the flange shall be 3 deg. Flanges shall be flat-faced at the full raised-face thickness (minimum) called (or in the ASME standards for the material of construction. Raised-face flanges may be offered as an option. Bolt holes shall straddle the horizontal and vertical centerlines. Bolt holes may be tapped when adequate space for nuts is not avaibble behind flanges. as noted in Table 1.1. Through bolt holes are preferred. When tapped holes are supplied, they shall be noted on the outline drawing.
5.2.2 Class 300 Option. As an option, Class 3(x) flanges in accordance with ASME 8165 or ASME 616.42 may be offered with prtssure ratings subixt to the manulacturer s casing pressure—lemperature limitations. Class 300 t1anges shall be flat-faced at full raised-lace thickness (minimum), or raised-face flanges may be offered as an option.
5.2.3 X and V Dimensions. All pumps. n!gardless of flange rating, shall conform to the X and Y dimensions shown in Table 1.1.
5.2.4 Heavy Hex Nuts. When heavy hex nuts cannot be used, the location shall be noted on the outline drawing.
NOTE: ASME B16.3 and ASME B16.42 indIcate the use o heavy hex nuts lur certain 1l.mge connLvlions. On mans B73 pumps, heavy Iws nuts rannot be used due to available space Standard hex nuts are often subsqltuqed. The use o standard hex nuts may not allow the achievement of full bob ietess, which may Impact proper gasket conpfrion. With most gasler materials, this does not reduce the gasket’s abIlity to properly seal, However, this a coiwideratlon for metallic and semimetallir gaskets where slgrnflcant preload may be required to achieve stalfident tightness.
