Monday, August 13, 2012

Re: [MW:15082] why PWHT is service requirement.

Hello Mr. Biplab Pal,

The main purpose of PWHT is to remove the residual stresses that incurred in welds & HAZ during welding. Residual stresses in Welds & HAZ will have high hardness and can develop cracks also. Now, if you have corrosive service like Sour, HIC, H2S, Amine etc. this high stress area will act as a crack initiator due to high hardness. PWHT will remove the residual stress & prevent possible failure. 

Hence in order to avoid failure, it is common practice to perform PWHT of CS & LAS piping/equipment is performed under corrosive service.

Hope this will help you.

Regards;

Purav Desai.

On Mon, Aug 13, 2012 at 3:52 PM, Biplab Pal <biplab.mech@googlemail.com> wrote:
Dear Exparts,

In refinery construction i have seen somewere PWHT is the service
requirement for piping.
I had a idea that PWHT is the requirement of Welding to improve the
Impact properties of Joints.
Can anybody give me any idea, why PWHT is done in service of fluid
other than impact properties.

--
Thanks & Regards
Biplab Pal
Mechanical Inspector (PMT)
YASREF Project

E-mail:   biplab.mech@gmail.com

Information in this email and any attachments is confidential and intended
solely for the use of the individual(s) to whom it is addressed or
otherwise directed. Please note that any views or opinions presented in
this email are solely those of the author and do not necessarily represent
those of the Company. Finally, the recipient should check this email and
any attachments for the presence of viruses. Myself accepts no liability
for any damage caused by any virus transmitted by this email.

--
To post to this group, send email to materials-welding@googlegroups.com
To unsubscribe from this group, send email to materials-welding+unsubscribe@googlegroups.com
For more options, visit this group's bolg at http://materials-welding.blogspot.com/
http://www.linkedin.com/groups/MaterialsWelding-122787?home=&gid=122787&trk=anet_ug_hm

The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.





--
Regards;

Purav DESAI

--
To post to this group, send email to materials-welding@googlegroups.com
To unsubscribe from this group, send email to materials-welding+unsubscribe@googlegroups.com
For more options, visit this group's bolg at http://materials-welding.blogspot.com/
http://www.linkedin.com/groups/MaterialsWelding-122787?home=&gid=122787&trk=anet_ug_hm
 
The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.
 
 

No comments:

Re: [MW:35289] Welding consumable for S355J2WP material

S355 J2 WP  is a weathering structural steel  It has better atmospheric corrosion resistance. Use E 8018 - W1/W2  Electrodes This is regular...