ANSI Torque Specifications for 300 lb raised face flanges
ANSI Torque Specifications for 300 lb raised face flanges
(OP)
Curious what is ANSI Torque Specifications for 300 lb raised face flanges. I am currently following the torque specifications for the gasket but I am cracking cast iron raised face flanges on control valves.





RE: ANSI Torque Specifications for 300 lb raised face flanges
What's the service? It can't be that severe - the CI valve bodies will only have a 250 saturated steam rating. Are the flanges cracking while the bolts are being tightened, or after the system has been in service for a while?
RE: ANSI Torque Specifications for 300 lb raised face flanges
RE: ANSI Torque Specifications for 300 lb raised face flanges
What type gasket are you try to use on The CI flanges that requires a 50,000 # bolt stress?
Who called out raised face on CI valves.?
RE: ANSI Torque Specifications for 300 lb raised face flanges
Gasket - Garlock compressed sheet
Customer provided the raise faced flanged CI valves, we are trying to mount them
RE: ANSI Torque Specifications for 300 lb raised face flanges
You might go back to the gasket supplier and tell him that the raised face flange is made from CI not alloy steel I’m pretty sure he will come off the 200 ft. lb. torque figure in a big rush. If says that this fiqure is required change gasket material or vendor.
Even if you did get some flanges to makeup any load imposed by the piping would probably break the flange. Even making up the flange using a 3 step tightening process would be tricky with the best of pipe fitters.
What is the process fluids and conditions?
RE: ANSI Torque Specifications for 300 lb raised face flanges
RE: ANSI Torque Specifications for 300 lb raised face flanges
A valve manufacturer can not know under what his conditions that his valve will be used so he cannot recommend a standard torque. The only thing in situation such as yours he could publish the maximum load his valve flange can sustain safely.
In your case the gasket is requiring a clamping load in excess of what the CI flange can sustain. All different gaskets have to seated, compressed, to function. To seat a particular gasket you have to have the physical components that will allow you to do this without undue forces on the other components, flanges and fasteners.
Don't get discouraged as bolted connections with gaskets are very complex subject of which many books and standards have been written.
RE: ANSI Torque Specifications for 300 lb raised face flanges
Any possiblity of getting the raised faces machined off or getting flat face flanges provided?
Edward L. Klein
Pipe Stress Engineer
Houston, Texas
"All the world is a Spring"
All opinions expressed here are my own and not my company's.
RE: ANSI Torque Specifications for 300 lb raised face flanges
Agree with you entirely. Cast iron flanges should not be Raised Face and should always be procured flat face as it's too easy to crack cast iron flanges (RF) with bolt loads.
mieklewis,
Suggest you tell the Customer he has got his specification for the valves wrong and they should have been FF.
RE: ANSI Torque Specifications for 300 lb raised face flanges
3/4" studs or bolts will require 1-1/4" wrenches if 2H nuts are being used. (15/16" wrenches if SAE fasteners are being used - which shouldn't be the case, but often is.) This will typically be a 1/2" drive ratchet with an 1-1/4" socket, and an 1-1/4" combination wrench, for 2H nuts. As long as the nuts are tightened evenly, in a crossing pattern, I can't imagine anyone (including me - and I go over 250 lbs) being able to - or NEEDING to - pull hard enough on these wrenches to crack the CI flanges. The torque wrench must have a very long handle indeed.
And we STILL don't know what the service conditions are. I've seen lots of 250 CI valves, strainers, etc get spec'd and installed on steam systems that OPERATE at 250 PSIG, but the safety valves are set for 300. "Oh, it's always been like that." That seems to make it OK, somehow...