×
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

PCV vs UG-126(b)

thread1203-389250

PCV vs UG-126(b)

PCV vs UG-126(b)

(OP)
Hi,

Does a globe valve with a pneumatic actuator (like a PCV), controlled by a self-actuated pilot valve (upstream signal) and fail position open meets with requirements of UG-126(b)?

Best regards

Torsani

RE: PCV vs UG-126(b)

No.

The exception would be in certain services if such a setup is designed so it was at least as reliable as a pressure relief valve. An instrumented control system that replaces a PSV typically has to be SIL 2 or higher.

http://people.clarkson.edu/~wwilcox/Design/hipps.p...

RE: PCV vs UG-126(b)

UG-126(b) refers to pilot actuated relief valve, not a pressure control valve. PCV, as per my knowledge, cannot replace relief valve under any circumstances.



https://www.law.cornell.edu/cfr/text/46/54.15-10

Dejan IVANOVIC
Process Engineer, MSChE

RE: PCV vs UG-126(b)

Pilot valves must be self-actuated. That is, they must be actuated by the pressure in the system and not by external sources such as electrical or pneumatics signals.

Therefore, the valve you describe does not meet UG126b.

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
Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close