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Re: [MW:8707] welding of dissimilar thickness

By Materials & Welding
Hi

Snce you have not stated specific construction code, assuming it as API, following are code requirements which is followed for piping in general:-

When the internal misalignment of pipe end exceeds 1/16 in, the thciker wall should be taperboard so that the internal surfaces are approximately flush, A 4:1 bevel is recommended, but the bevel should jot be greater than 30 deg. 

This reduces stress concentration, fecilitates root pass welding and improves inspection of joint using radiography.

Hope you will find this useful.

Regards
Manpreet Singh
Welding Engineer


On Sat, 11 Dec 2010 22:19:53 +0530 Marcelo Soriano wrote
>
dear friend,
tappering at least 30 degrees is to be done in the thicker base metal to be match the other base but make sure that you have approve procedure that signed by your client and meet the design thickness..
>

>
From: Vikas Bhandari <vikas.bhandari349@gmail.com>
>To: materials-welding@googlegroups.com
>Sent: Friday, December 10, 2010 5:20:22 PM
>Subject: [MW:8668] welding of dissimilar thickness
>
>Dear all

>
there is 22 Chrome pipe (18.3thk) to pipe flange welding(14.3 thk mm). What are the precautions that need to be taken for welding them? How would be the edgepreparationdone for the thicker pipe?

>
Best regards

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>

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>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/
>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.
>

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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/
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.

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