gvalves0164
Mechanical
- Jan 3, 2012
- 17
ASME Section VIII DIV 1 Appendix Y states that the rules apply to flat Face, Identical and Non-Identical Flange Pairs where uniform metal to metal contact occurs outside bolt circle. The rules apply for negligible gasket loads (ie. Pressure Energized O-ring Body Seal) HG=0. In addition, Section VII DIV 1; Appx Y-1(b)states ".....It assumes that the seal generates a neglible axial load under operating conditions. If this is not the case, allowance shall be made for a gasket load HG dependent on the size and cnfiguration fo the seal and design pressure...". I interpret this to cover non-pressure energized sealing methods (ie. spiral wound gaskets vs o-rings).
My question is if spiral wound gaskets are utilized for Body Sealing on two piece ball valves (resulting in metal to metal contact outside the bolt circle), do rules apply for using HG*hg in the formula for Flange Thickness Calculations?
My question is if spiral wound gaskets are utilized for Body Sealing on two piece ball valves (resulting in metal to metal contact outside the bolt circle), do rules apply for using HG*hg in the formula for Flange Thickness Calculations?