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[MW:12389] Need advise to clarrify client - Dish head stress relieving simulated PWHT test panel

By Materials & Welding
Dear Friends
 
Please offer me your suggestion how we can settle the following case.
 
We fabricated and supplied one pressure vessel to one of our client two years back. Now only they have reviewed our documents and come back with following observations.
 
Code of construction is ASME VIII Div 1 and AS1210 and AS4458, Material SA 516 Gr 70, thickness 30 mm,
 
Our vessel dish head is Stress relieved as per ASME viii Div 1 code requirement, but we have not done any simulated PWHT test panel for this stress relieve treatment.
 
 as per AS 4458, Unless any mechanical  test is done to prove Stress relieved components are restored to their original material properties, normalising is the preferered heat treatment for cold formed components.
 
It is obvious from above that either we have to do SR with Simulated PWHT test panel or Normalising of dished head.
 
Actually we have overlooked AS 4458, so we have only done SR without PWHT test panels, so no mechanical testing was done.
 
At this stage we cannot do normalising as plant is already running.
 
At this stage, we do no have stock of same heat number plate.
 
Please suggest how we can answer this observation.
 
Can we say we have overlooked AS and SR done as per ASME Viii Div 1 as a normal practice in South east asia.
 
We hve not done any Hardness test  being carbon steel material.
 
Thanks
 
 Murugesan
 
 
 
 

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