×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Contact US

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!

*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

Pressure relief valves and pressure regulators - what's the difference?

Pressure relief valves and pressure regulators - what's the difference?

Pressure relief valves and pressure regulators - what's the difference?

(OP)
What is the difference between a pressure reducing valve and a pressure relief valve? pressure-reducing/regulating/ relief/release - There are so many different options available!

I read this article on Fluid Controls that did a really good job of explaining pressure regulators, but I am a bit lost on the difference between regulators and relief valves.

RE: Pressure relief valves and pressure regulators - what's the difference?

A relief valve is intended to stay closed and sealed until a limit pressure is exceeded, at which point it opens fully. It may not re-close (some boiler safety relief valves operate this way, as do burst discs and similar) or may re-close only at a substantially lower pressure than the opening pressure (perhaps 80% of the opening pressure).

A pressure regulator will be designed to open and close in a very narrow band of pressure, and may or may not really shut off tightly. How narrow that regulation band is, and how repeatable the band is across a flow rate range depends a lot on the design of the regulator...and money.

RE: Pressure relief valves and pressure regulators - what's the difference?

Additionally, a regulator limits the pressure on its downstream side by only allowing fluid to pass until the set pressure is reached. The fluid that passes through the regulator is intended to be used by the process. A pressure relief valve controls the pressure upstream from it by dumping excess pressure to the atmosphere/return/drain/whatever, often as mentioned by btrueblood without resetting.

There are some processes (usually liquid) that use back-pressure regulators to maintain the desired pressure upstream in the processing system. They are more similar to pressure relief valves, but they dump excess pressure in a much more controlled manner into the return.

RE: Pressure relief valves and pressure regulators - what's the difference?

Does anyone have any preferred valve suppliers for this type of situation?

There's just so much variety and there's distributors then brands etc - Im looking at doing a placement with BM Engineering next year anad wondereded if anyone had any experience with them and their products??

RE: Pressure relief valves and pressure regulators - what's the difference?

YT has some video animations of control valve operation, which might help. Search for "control valve animation". Some control valve manufacturers have these animations on their websites. I am most familiar Cla-Val (https://www.cla-val.com/). Cla-Val also has diagrams that show how the valves are plumbed and how they can be used in a system.

============
"Is it the only lesson of history that mankind is unteachable?"
--Winston S. Churchill

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! Already a Member? Login


Resources

Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a part’s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. Download Now

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