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[MW:529] Pressure Vessel failure during Hydrotest in China - Nov 07

By Materials & Welding

Dear Members

 

Our curiosity does not end after just seeing the pictures, is n’t it? We must find out the real reasons and failure causes, is it a designers, material selection/supply, fabrication, PWHT….. Where is the fault lie? The lack of information provided with the impressive set of pictures begs a lot questions concerning the failure.  

Viz:  What is the metallurgy?  Thickness? Is it a Cr-Mo steel? Was it properly preheated and PWHT'd?  Was the vessel correctly designed per the appropriate code?  Were the welds acceptable and per code?  

We can see a fractured thick shell around a reinforced opening.   Looks like internal lining.  Is it clad or a camera flash?

Please if someone has more details of this failure, I would like to know.  

The only conclusion I draw from this is that we should continue to be critical of material sources and equipment suppliers and only buy from reputable sources.  Does this rule out Chinese sources?  Not necessarily, but we do need to be diligent in our qualification of new vendors.

 

 

Best regards

Raghuram Bathula

From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of Agrawal Sunil (Mumbai -Stequ)
Sent: Tuesday, January 22, 2008 9:01 AM
To: materials-welding@googlegroups.com
Cc: PED2000@googlegroups.com
Subject: [MW:511] Pressure Vessel failure during Hydrotest in China - Nov 07

 

A forwarded mail but very important. The message "Be careful when reviewing

& approving materials / equipments from China".

Check the attachment

 

 

Best regards,

 

Sunil S. Agrawal


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