ASME Safety Valve

[FredRosse]

ASME Application Question
I have an ASME Safety Valve, 100 psi, rated for steam service, with an ASME "V" stamping. Can I use this valve on a Fired Power Steam Boiler, (Sect 1)?

 

[metengr]

Yes. Please be advised that the set pressure and relieving capacity for this valve should be evaluated for use on the steam outlet section of your boiler.

 

[FredRosse]

My question is with respect to the stamping, for example I have other safety valves, ASME stamped "HV" and "UV", as well as Valves stamped "V". What is the distinction between these stampings, and which ones are qualified for use on a fired power steam boiler? The set pressure and capacity numbers (PPH) stamped on the relief valve are OK for the boiler.

 

[timmckee]

Hi Fred,
To answer your first question, the "V" stamp is the Section I stamp for BOILER safety valves, so yes you can use it on any Sec I Boiler as long as it meets the needed pressure and capacity, which you said it does.

Now for "HV" and "UV" stamped valves, that's a different story. They are relief valves, not safety valves, manufactured under Section IV HEATING Boilers and Section VIII, Div. 1 PRESSURE VESSELS respectively. These valves are generally designed for liquid service, not gas or vapour. The major difference being they open more as the pressure builds where as the "V" stamped valves "pop" to full opening at their set pressure.

Now having said all that you could probably use a "V" stamped valve on a Pressure Vessel or a Heating Boiler as long as the set pressure and capacity is a match. I'd dig through the ASME codes first to check though.

Hope that helps.

 

[FredRosse]

Thanks for the info, now all is clear.