gasket seating stress
gasket seating stress
(OP)
Dear all,
I have a weld neck flange reduced bolt circle with dia 9.5" OD with bolts 3/4" dia and mating flange is flat face 6" flange. I am just wondering the seating stress of the gasket and the seal. Can anybody suggest what type of gasket to be used and the thickness. My design pressure of the vessel is 150 psig air service. The material of the flange is SA 516 Gr.70. Also, I am concerned about tear out from bolt OD to edge of the flange.
I have a weld neck flange reduced bolt circle with dia 9.5" OD with bolts 3/4" dia and mating flange is flat face 6" flange. I am just wondering the seating stress of the gasket and the seal. Can anybody suggest what type of gasket to be used and the thickness. My design pressure of the vessel is 150 psig air service. The material of the flange is SA 516 Gr.70. Also, I am concerned about tear out from bolt OD to edge of the flange.





RE: gasket seating stress
Be careful. You need to check that the thickness of the flat face flange is suffiient to accommodate the bending moment caused during bolting-up of the joint. Normally a flat faced flage is mated to another flat faced flange so that you do not get the bending moment caused by the bolts.
RE: gasket seating stress
Also, I would like to know where the thickness of gasket is used calculating the minimum load to seal the gasket in Wm1 and Wm2.
RE: gasket seating stress
I'm not sure what you mean by "reduced bolt circle", but with standard dimensions tear out is not a problem.
Regards,
Mike
RE: gasket seating stress
By bolt circle is 9.5" dia and the bore diameter is 8.063" and we are using studs (instead of bolts) with 3/4" dia studs. I am using studs because I do not have room to use nuts.
RE: gasket seating stress
It would appear that your 6" mating piping (if any exists) would be no larger than about 6.36" ID, it is possible to reduce the flange ID?
Since it seems you are studding into your flange, will you be able to break this joint with the studs in place?
Regards,
Mike
RE: gasket seating stress