Cyrogenic Valve failure

Have you asked the valve manufactures/suppliers? If it's not fit for purpose, they must either fix it or give you your money back (possibly with damages) if they were told about the working conditions, and sold it to you as suitable.

to what astm standards were the materials forging s parts procured?

Your question is unclear, are you the manufacturer of the valves?

What is failure mode? are all valves failing same way?

A little more information please.

milo

Propane, Penthane are similar to Butane, in that the valves must have special gasket and valve materials.

Normal water, air and hydraulic valves seats will not survive for long with these gases...

I'm not a chemical engineer so I dont know why, I just know you must specify useage of these gases / vapours when specifying a valve, so the correct sealing materials are supplied.

John.

What part of the valve fails? The pressure or the stem and seal?

What is the nature of their failure? You will have to explain the failure before anyone can respond. Do they fail to open do the stems leak, does the body crack, does the valve leak through? It seems you have experienced this more than once so you must know the nature of the failure.

Just like others I am curious to know about the type of failure.

Does it leak?

Does it stick?

Has this valve been tested per BS standard 6364 which details testing of cryo valve?

Just Stainless material does not make a cryo valve.

We Import valves,Step#1 did you inform the manufacture about the specific application,Yes,contact supplier about the valve not functioning properly,If no, you get what you pay for,in addition any respectable manufacturer or supplier WOULD NOT SUPPLY OR MANUFACTURE a valve without ALL THE SPECS.