×
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

ASME B16.34 - Off spec valve classes

ASME B16.34 - Off spec valve classes

ASME B16.34 - Off spec valve classes

(OP)
I've been working on specifying a wye pattern globe valve and I've noticed that it seems quite common in valve catalogs to specify these valves as class 1690 and class 2680. Are these classes related in any way to the ASME 16.34 valve classes? I cannot find a spec anywhere that uses these numbers yet the manufacturers tend to refer to ASME B16.34. Can anyone explain this to me? Thanks.

Grant

RE: ASME B16.34 - Off spec valve classes

Yes they are related to ASME B16.34 Limited Pressure Class. Do a google search for "Class 1690 Pressure rating" and you will find numerous valve manufacturers offering product with these ratings. You should also look at B16.34 section for limited class to understand the differences with the standard class ratings and the specific rules. For example, limited class is restricted to NPS 2-1/2 and smaller, weld and thread end only. Only specific body shapes are allowed. Limited class uses a different equation to establish the pressur/temperature rating for group 1 and 2 materials, which can yield a higher rating than standard class. The benefit is that you can get a less expensive valve with sufficient pressure rating and conformaning to the required code without using the next higher standard class. For example, if your system operating pressure is 1,500 psi, and class 600 max. pressure is 1480 psi, you must either go to class 900 or use the limited option.

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