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[MW:2652] Re: Welding after PWHT

By Materials & Welding
what is the material?
Generally these trappings does not require PWHT on carbon steel, even
when welded on a PWHT'ed line. refer para 331.1.3 for governing
thickness.

On Jul 10, 10:39 am, Tulasi-BV ADH <tulasira...@gmail.com> wrote:
> Friends,
>
> While fabricating pipe spools as per ASME B31.3, A pipe welded with an
> Orifice flange was undergone PWHT in the furnace ( the branch nozzle on the
> orifice flange was not welded before PWHT ) and the contractor wants to
> weld the branch nozzle on the Orifice flange after PWHT & doesn't want to
> carryout local PWHT.
> Is it acceptable???????  or the preheat & inter pass temperature shall be
> minimum 150 Deg Celsius.
> Regards,
>
> Tulasi Ramu
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