Do NOT use a rubber gasket. They're for full face flanges at relatively low temp/press. The stresses generated on gaskets on most raised face flanges (e.g. your 4" 300#, assumed to be ASME B16.5?) are beyond what rubber is designed to do. I agree with Gordon's suggestion of using a non-asb. fiber re-inforced material (e.g. Klinger C-4401). Something with a Nitrile binder for the petrol.
A bolt stress of 30,000 psi is a good start. For this size flange (8 bolts, 3/4" size, appx. 14.5 sq. inches stressed gasket area), you'll generate around just under 6k psi load. My data shows min. of around 1500 psi to seal at your conditions, so you're well above. 30,000 psi stress on a well lubed 3/4" bolt is about 100 ft-lbs.
Good Luck!
-Davis
can anyone recommend a gasket material for # 2 fuel oil... The job spec is calling for Buna-n...but we have heard of leaks at higher pressures with a rubber type gasket...... the flanges are raised face and the pressure is 200 psi, the temperature is ambient...... also what would be the recommended the bolt torque. the size is 4" 300 rasied face carbon steel flanges ....any one with experience with fuel oil systems ?
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[Non-text portions of this message have been removed] Received on Fri Jan 30 14:24:00 2004
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