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[MW:17937] Regarding PWHT soaking, cooling rate /heating rate

By Materials & Welding

 

Dear Expert,

                         I need to clarify regarding the heating rate/cooling rate during PWHT as per B31.3, I referred code but it is not giving clear idea or maybe I can't interpret  properly. Please advise with code backing. If suppose I have P NO 1 material of thickness 46 mm than what would be the

1. soaking time

2. cooling rate

3. heating rate


regards

shashi

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Comments

htphone co., Ltd said…
Above 315oC
heating rate & cooling rate: shall not exceed 335oC / hr
holding time: 1hr(minimum with thickness up to 50mm)
holding tem: 600oC-650oC
June 16, 2013 at 10:46 AM
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