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[MW:13345] RE: 13340] Re-expansion of tubes for Air Fin Cooler.........

By Materials & Welding

Dear Vinod,

 

Recommended for DSS Material Expansion required for 3 – 5 %.

 

The main thing , you need to know whether AFC for Tube Sheet Holes were Design with Groove or not , coz your references said the tubes also welded .

 

In certain procedure were adopted with references from Client Specification. It doesn’t show groove means your tubes was performed with Light Expansion only ( close the clearances between tubes to tube sheet ) then the welding tubes need a degree for bevelling for strength weld.

 

Regards

Mus7.

 

From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of Vinod Jotwani
Sent: Wednesday, 28 December, 2011 9:41 AM
To: materials-welding@googlegroups.com
Subject: [MW:13340] Re-expansion of tubes for Air Fin Cooler.........

 

Dear Experts,

 

We have one of our fin fan cooler leaking from tube to tubesheet joint. The tube material is Duplex stainless steel.

 

We would like to carry out re-expansion of the tubes, your advise is needed for %age expansion allowed when these tubes are to be re-expanded. The tubes are in operation since last one year in Sour Water Recovery Unit ( H2S service).

 

Also if some body can share their experience in case of leakage even after re-expansion how to repair the tube to tube-sheet joint. For information the header is welded constuction.( Ref attached file )

 

 

Thanking you,

 

Vinod



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