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Re: [MW:8833] WQT

By Materials & Welding
Dear Rishikesh

1) Welding Procedure is qualifiied only when the Mechanical tests are
passed. You cannot start welding before a procedure is qualified.
Do not look at WPS/PQR as a code requirement. Look at it as a Trial
procedure to verify the procedure you are going to use for production
welding will serve the purpose. Your tiral procedure fails means your
production is also going to fail. This should be the attitude.

2) NDT is to verify the weld is free from unacceptable defects.

A weld is free from defect in NDT does not mean it will pass the
mechanical tests. Mechanical test is to ensure the joint and weld
metal is have minimum tesile properties, impact properties,
hardness, microstructure and to ensure the compatibility of weld metal
to base metal. These can be verified only by mechanical testing.

3) Welder qualifiaction - is to test the ability of weld metal to
produce a sound weld. Code allows this can be done by visual and RT.

When welder qualification is comibed with procedure qualification and
test piece fails to pass mechanical test, then welder qualification
also becomes invalid eventhough the RT is passed.

If mechanical test is failed then all joints need to be cutout.

Thanks

Murugesan


On 12/20/10, Rishikesh Singh <01hrishi@gmail.com> wrote:
> Dear Sirs,
>
> I want to know that in welder qualification test if the NDT is cleared and
> the Destructive testing is awaited then can we start our production weld
> with these welders and what happen in case the Destructive examination is
> failed please reply Sir i m suffering with this problem please.
>
> Regards,
>
> Rishikesh Singh
> Project Engineer(Bharuch)
> A.I.P.L.
> 8128769028
>
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