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[MW:11809] Re: weld stop during root pas

It is not recommended to leave the unfinished root pass or even a root
pass covered by a hot ass to the second day cause the stresses applied
on the joint by geometry (if it is pipeline so you have full pipes
weight, or if it is piping so you have a fitting attached) and even
you are fitting the joint up on a temporary support, then there will
remain some load on the joint and the amount of the deposited metal in
the groove will not be able to carry that load and it will lead you to
crack formation in the root pass

it is advisable to leave at least the hot pass full covering the root
with good support and keep it without cleaning and do inter-pass
cleaning only when you are going to deposit the filling passes on the
second day and that because of keeping as much as possible of the
deposited thickness without grinding and also not to let the metal be
rusty by the second day and again you will have to clean it more and
reduce the thickness of the hot pass more which will may take you to
burn-thrugh

finally you can apply preheat before continuing the welding as per the
original preheat requirements in the WPS

regards,

Mostafa

On Jul 16, 10:29 am, jagdish patil <jagdishpatil...@gmail.com> wrote:
> Dear all,
>
>  I would like to know during welding at root pass stage we stop some reason,
> but  we can start continue welding on next day without any test is it
> possible.
> if not possible give me the specific reason.
>
> regards,
> JAGDISH

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