×
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 B31.3 Design Pressure Surge Vs Overpressure

ASME B31.3 Design Pressure Surge Vs Overpressure

ASME B31.3 Design Pressure Surge Vs Overpressure

(OP)
B31.3 requires that the design pressure includes for surge at 301.2.2 b)In 302.4 f) 1) occassional variations are allowed up to 1.33 times design pressure.

Is it the intent here that the system should be designed such that the occassional loads do not create pressures that result in stresses above basic allowable. However in the event that there is a malfunction, unexpected event etc and the surge pressure doesnt not exceed that which creates stresses > 1.33 times basic allowable stress then the piping system remains in accordance with the Code? Given of course all the conditins of 302.4 are met.

For instance can one design a control system that keeps the piping operating inside the design pressure under surge conditions but if that control system failed or there was manual intervention then the system pressure could be allowed up to 1.33 times the design pressure.

Geoffrey D Stone FIMechE C.Eng;FIEAust CP Eng
www.waterhammer.bigblog.com.au

RE: ASME B31.3 Design Pressure Surge Vs Overpressure

stain,

It is normal and customary to consider the installation of a relief valve on piping systems to protect them against the extreme conditions where the pressure loading exceeds 1.33.

If the piping contains a liquid, a very modestly sized relief device can give a lot of protection....


MJC

  

RE: ASME B31.3 Design Pressure Surge Vs Overpressure

(OP)
Hi MJCronin,

Thank you for your reply but it doesn't address the question as such but raises an interesting point.

What pressure would you set the relief valve at? 110% of the design pressure or 110% of the occassional pressure (1.333 times design)?

Geoff

Geoffrey D Stone FIMechE C.Eng;FIEAust CP Eng
www.waterhammer.bigblog.com.au

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