×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

WOG or CWP Valve for Steam

WOG or CWP Valve for Steam

WOG or CWP Valve for Steam

(OP)
I have an existing system that needs evaluation for compliance to B31.3 (as referenced by our local boiler code).  The system is a deaerator for boiler feed water.  One thing I have noted is that all of the ball valves on the unit do not have WSP ratings. Four have a CWP rating (1500 psi) and the other a WOG rating (2000 psi).

The deaerator has twin 25 psi relief valves and contains water and steam used for spray type deaeration.

The spec sheets on the valves list a max operating temp of 450F and 380F.

Are these adequate for the service?  

RE: WOG or CWP Valve for Steam

The four that have a CWP rating of 1500 psi, what standard are these made to - are these ASME B16.34 Class 600 valves ?  If so, you can review that standard to determine the working pressure rating at elevated temperatures.

For the WOG rated valve, you would need to determine what standard it was made to (likely an MSS standard, perhaps SP-108) and see if that standard could provide you working pressure ratings at elevated temperatures.

Unfortunately, knowing the cold working pressure rating and the max temp doesn't actually tell us anything about pressure ratings that may apply between ambient and the max rated temperature.

RE: WOG or CWP Valve for Steam

(OP)
Both valves are made to B16.34.

I missed adding in my original post that those temps are at 25psi. The valve spec has a temp vs pressure graph.  

RE: WOG or CWP Valve for Steam

Not sure what the problem is if you have a valve temperature vs. pressure graph. Compare the valve rated working pressure at your design maximum temperature to the required design pressure ?

Am I missing something ?

Or is the question that you want to validate the temp vs. pressure charts you have ?

RE: WOG or CWP Valve for Steam

(OP)
My concern was that the valves don't have an official WSP rating. I didn't know if this was a requirement. Or if this could be overcome with temp vs pressure rating.  

RE: WOG or CWP Valve for Steam

We use ASME B16.34 valves quite regularly in steam services based upon the pressure / temperature ratings.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources