Tungsten as a spring material is no longer used as a material by PRV manufacturers. Where Tungsten steel as a spring material has been specified, it is likely that an 'Alloy Steel' (such as H12) will be offered. Tungsten springs have been largely replaced by Chrome Steel or Alloy Steel dependant on the application. Depending on manufacturer, valve size and application, even Inconel X750 may be used as a viable alternative.


*** Per ISO-4126, the generic term
'Safety Valve' is used regardless of application or design ***

*** 'Pressure-relief Valve' is the equivalent ASME/API term ***

Nasim,

It is important to be explicit and not to confuse terms.

As so well explained by the Obturator above, we are assuming by your use of the word "tungsten" you are trying to say "tungsten steel" and not the metal tungsten.

You are probably dealing with some very old data sheets where "tungsten steel" implied a premium and costly material.

But the world has moved on and there are better and lest costly alternatives

When you mean "chrome steel" say so ... do not say "chrome". Similar rules apply with tungsten steel

MJCronin
Sr. Process Engineer

Thanks MJCronin. Yes, you are right.. I am referring 1997 PSV data sheet. Finally i came to know that there is a typo error in the PSV data sheet. Based on the spring part number, we confirmed that spring material was "Alloy Steel". However in the data sheet, it was mentioned that it was mentioned that " Tungsten".

When i received "The Obturator" feedback, i communicate with PSV manufacturer and finally i got confirmation. Now we are correcting the data sheet error.

Thanks a lot for your support..

Thanks
Nasim