Re: [MW:12847] Nick break test failed

Dear Mr.Calva,

1. I think U can not support. My suggestion is contact to your customer and tell that it has failed because of Defects (as you have mentioned) and not because of process issues. Normally it is acceptable to carry out re-test in such cases. Propose to carry out twice number of tests than asked for fresh WPS.

As a future caution make a practice to perform RT as suggested by Mr. Dinesh so that defective area does not undergo mech testing.

2. Purpose of these tests are to check the ductility of weldmetal and haz, they are not soundness test as far as Procedure qual is concern.

3. Propose ur customer that we are changing the welders to avoid the defect.

hope it'll help.

Reg

On Wed, Nov 2, 2011 at 11:00 PM, Eduardo Calva <eduardocalva@hotmail.com> wrote:

Process: WPS qualification for SMAW through thickness double repair
Electrodes: root pass E-7018, HT, fill and cap E-7018-1
Code: API 1104
Pipe Diameter PQR: 24"

ISSUE: 2 of 4 specimens failed on Nick break test showing porosity and slag.

My questions:

1.- Can I support with only 2 passed test that the WPS is approved?
2.- Why codes ask for soundness tests like bend and nick break for WPS qualification?, I mean we would just need to test mechamical properties like tensile, hardness, charpy, etc
3.- It is a fact that the cause the test failed was because welder workmanship not the pocess is bad

Thanks for help me.

Eduardo Calva

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