Calculating blind flange min. thickness
Calculating blind flange min. thickness
(OP)
I'm trying to figure out the minumum thickness of a 36" blind flange. I'm making a crud trap with some big HDPE pipe, and am going to use 2 blind flanges on the ends. I found a formula in Perry's:
t = d(3P/16S)^0.5
where d=inside diameter, P=internal pressure, S=allowable stress, and t=thickness
If P=70psi, d=36", and S=55,000psi for A-285 carbon steel plate, I get 0.55" thick plate for safety factor of 1.0. I'm going to rubber-line the blinds too.
Is this an appropriate equation for this application? What is an acceptable safety factor? If I use 1" plate I would have a S.F. of 1.8. A stock 36" 150# blind flange is 3.5" thick, and that is far too heavy.
t = d(3P/16S)^0.5
where d=inside diameter, P=internal pressure, S=allowable stress, and t=thickness
If P=70psi, d=36", and S=55,000psi for A-285 carbon steel plate, I get 0.55" thick plate for safety factor of 1.0. I'm going to rubber-line the blinds too.
Is this an appropriate equation for this application? What is an acceptable safety factor? If I use 1" plate I would have a S.F. of 1.8. A stock 36" 150# blind flange is 3.5" thick, and that is far too heavy.





RE: Calculating blind flange min. thickness
RE: Calculating blind flange min. thickness
RE: Calculating blind flange min. thickness
RE: Calculating blind flange min. thickness
aybee: so that formula (t = d(3P/16S)^0.5) is only good for a blind that is inserted between two flanges in a line? I guess what I'm looking for is a blind END flange equation?
Hydrodude: <<Be sure your flange is fused to the pipe and not a mechanical dresser type>>
I'm not quite sure what you are referring to here. The HDPE hasn't been fabricated yet, but I called out 36" flange adapters for both ends. They would have carbon steel backing rings that put the 'squeeze' on a HDPE lip that forms the actual seal against the rubber-lined C.S. blind.
Could you elaborate?
RE: Calculating blind flange min. thickness
RE: Calculating blind flange min. thickness
RE: Calculating blind flange min. thickness