Magnetic Particle or Dye Penetrant inspection

[lgracio]

Anyone can help me why my client are requiring these additional tests below for raw material suppliers for pieces like Weldolets, Thredolets, Flanges and round forged bars?
1. The PMA's are not requiring these tests. Where it is applied by the ASME code?
2. If my supplier are not able to do these tests, can I do after during manufacturing process? Any limitation by ASME code or PED?

Additional tests: "Magnetic Particle or Dye Penetrant inspection, after heat treatment, of 100% of materials that undergo forging is required per applicable ASME Standards."

Luís Grácio
Mechanical Engineer (Energy Solutions)
Portugal-Setúbal

 

[vpl]

LGracio:

Probably the easiest way to find out is to ask your client. If it's in his spec, and you've bid on that, then you're obligated to do it, even if there is no good reason.

Patricia Lougheed

Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of the Eng-Tips Forums.

 

[mizzoueng]

Are these going on a pressure vessel?

The B31.1 code says that you must perform testing on all welds, forgings is another matter. I typically do not deal with those.

I have requested PT and MT (but not a whole lot) on o-let welds to confirm that there is no porosity in the weld surface.

I would assume that the PT test would ensure that there are no stress induced cracks in the forgings and that the MT test was to confirm the heat treat was done correctly.

But ask the client what they are looking for, if they ask for this often they should be able to give you a straight answer.

 

[noblegas]

lgracio:
1-As an example, when you look at ASME Sec.IIA SA182 specification your client's request is mentioned as supplementary requirement. Please see Par.S4.1 and S5.1. And it is mentioned at Par.15.1 and 17.2.7 that the supplier should provide the material is being furnished in accordance with the purchase order and certify any supplemantary testing required by the purchase order. You have to know if it is mentioned as requirement in the client's documents and purchase order or not.
2-My opinion your client wants to see the surface imperfections before welding. As you know If you don't do any pressure testing after welding, you can never find defects at welded side of materials by applying these tests. If you do pressure testing and apply the tests during manufacturing and find defects on material it's repair will cause additional cost.It would be better to provide your clients request.

 

[racookpe1978]

MT or PT would really only be needed (critical) AFTER they are welded on the final part/pipe.

The failure of a weldolet (or threadolet) is in the weld attaching it to the pipe, not "through" the part itself. Further, a PT will be able to check the surface of the (cast) part - so if a part had an internal defect - that did not make it all the way to the outer surface (how can you PT the interior with its rough surface?) you would not find it anyway.

A MT "might" find internal defects - but in these kind of pieces with irregular internal surfaces, it is extremely difficult to reliably and honestly say "I did an MT test on the part and there are no internal defects." You could say "I did an MT test of the part and found nothing unusual" - but that doesn't mean you would have found the defect anyway.

Your final Hydrostatic test of the system will verify that ALL of the new weldolets (or threadolets) and all other parts will withstand a pressure greater than any expected in operation. That is WHY you do the hydrostatic test. The MT (PT) of the welds before that hydrostatic test is to very that the welds holding the parts together are good.