Acceptance Criterion under ASTM A36

[engdrve]

Hi, Mechanical engineer looking for advice from a metallurgic engineer.
We have ordered the fabrication of an in take gate under the material specification ASTM A36 or ASTM A572. Due to de size of the piece the final assembling has to be done on site.
During the weld joints preparation for the final assembling discontinuities were detected in the plate by P.T. Examination. So we proceeded to carry out U.T. examination and we found lamination defects. The maker was informed and brought to site for inspection.
Now the maker is alleging that under the ASTM A36 norm there is not requirement of U.T. examination for the purchasing of the material. The maker is also alleging that the defects are inclusions characteristic of the process of elaboration of the steel plate, that we are applying the norm ASTM A578 which was not specified. Can any body advise me if it is possible and what will be the criterion for rejecting the plate due to lamination defects under ASTM A36 and ASTM A572 specification?

 

[JoeTank]

It sounds to me like your material supplier is correct. The UT examination is not standard practice nor required by ASTM A36. If you reguired the UT exam, you should have specified it in the PO. How thick are the A36 components? Has your engineer determined that the laminations are detrimental to the performance of the intake gate.

Joe Tank

 

[EdStainless]

I have to agree with Joe's interpetation. You are always free to apply additional tests and reject material, but your supplier is only liable for the ones specified in the purchase agreement.
If the lamination was so serious that you found it without machining, PT and UT, then you might have an argument under the workmanship clause. Since you only found this with additional testing it is your problem.

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[gtaw]

My experience has been the supplier will replace the material in which there is a "defect" if it is observed and reported before any fabrication has been done on the raw material. In other words, once the piece is cut, drilled, bent, welded, etc., you own it.

Best regards - Al

 

[dbooker630]

In some cases it is not possible to whether a material is sound unless you mechanically work it. Good example is castings. Shrinkage and porosity is not necessarily evident at the surface, sometimes it's only revealed after drilling or turning.

If standards were not called out in the PO as JoeTank recommends, all you have to stand on is whether it is "fit for use" and you still may have a fight to recover any fabrication costs beyond the material cost.

 

[metengr]

Buyer Beware.

 

[engdrve]

dbooker630
So, the opcion is to let our structural engineers to demonstrate theoretical wise that the plates will not fit for the design porpose?. What about, what is indicated in ASTM A6-06. 9.1 Note 4. Structural products tha exhibit injurious defects during subsequent fabrication are deemed to comply with the appilcable product specifications. and 17.2 ¨The purchaser shall have the option of rejecting structural product tha exhibits injurious defects subsequent to its acceptance at the manufacturer´s or processor´s works, and so notifying the manufacturer or processor.

 

[CoryPad]

engdrve,

Yes, "injurious defects" is what you need to prove so that the vendor takes responsibility.

Regards,

Cory

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[JoeTank]

engdrv,
Have you determined that the defects are not accepatble? Since laminations are known to be present in most thick plate products, I think you may find some resistance for the plate producer to do anything other than replace the material in-kind. How thick is the material? We have typically repaired the minor defect area and proceeded with manufacture. I'm speaking about an application wherein the lamination was not detrimental to the use of the plate.

Joe Tank

 

[engdrve]

corypad
Sorry, I wrote it incorrectly.
Structural products that exhibit injurious defects during subsequent fabrication are deemed (NOT) to comply with the appilcable product specifications.