×
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

PWHT

PWHT

(OP)

Hi,

I have some query related with Local PWHT of piping spool as per B31.3.

1)Throught out heat tratment cyclce (resticted range) the temperature differential bewteen thermocouples registering peak temperatures shall be within limit of + or - 40degree celsius as per ASME Sec VIII , However what about as per B 31.3, 31.4 & 31.8 ?

2)As per B 31.3, 31.4 & 31.8 what will be the restricted temperature range for P1 and other materials ? And where it has specified in code ? (Genarally resticted temperature range, 300degree celsius following in site)

3)During Pwht heating or cooling rate not maintained as per WPS requirment,then whether re-pwht can apply on same joint ,How many times can do re -pwht on one particular weld joint as per the B31.3 ,B31.4 & B31.8 ?


QC7

RE: PWHT

1. There is no definition of permitted deviation of T/C measurements during heating - only the minimum/maximum PWHT temps.
2. Restrictive temps are also provided in ASME IX. You need to ;look at the requirements of both the piping codes and ASME IX.
3. There a no restriction r4egarding number of times one can perform PWHT on a weld not subject to PWHT. When impact testinfg is required, ASME Section IX provides the limits on aggregate time at temp.

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