?Need torque specs for flange/gasket?

look in ASME PCC-1 "Guidelines for Pressure Boundary Bolted Flange Joint Assembly "

sprintcar,
You indicate that the cast iron pump flange is raised face or the piping is raised face. Normally cast iron pumps are supplied with flat faced flanges and the attached piping should have flat face also. This is to prevent excessive bolt loads being applied to the cast iron (if one or both flanges are RF) which could crack the cast iron.

Thanks arto - can anyone email me the tables? We don't have that one in the library here


Keep the wheels on the ground
Bob
showshine@aol.com

Pump flanges are either flat or raised - When writing instructions you must allow for the worst case. You're right .... they Will break raised face flanges - despite the instructions

Keep the wheels on the ground
Bob
showshine@aol.com

A nice trick for bolting flat face cast iron flanges to raised face flanges is to use a spacer ring on the raised face flange. A spacer ring is 1/16" thick (the same height as the flange raised face), with an ID 1/32" larger than the flange raised face OD, and an OD equal to the flange OD. The flange bolt pattern is punched into the spacer ring. This spacer ring fills the gap outside of the flange raised face, essentially turning it into a flat face flange, leaving no possibility for flange bending. Use a hard compressed, non-asbestos for the spacer ring. You'll need a full face flange gasket now, so adjust your bolt load to provide the necessary stress on this larger gasket area.
Many class 150 flanges don't develop sufficient assembly stress for full face gaskets, so you may need to look into reduced area full-face gaskets. A gasket manufacturing company in CA called Inertech markets a reduced area gasket design called "OPRA"- One Piece Reduced Area.