MPI or Penetrant dye for ASME VIII
MPI or Penetrant dye for ASME VIII
(OP)
Hi,
Can anyone help me understand where ASME VIII Div 1 tells me how to select MPI or penetrant dye examination of welds on a non-heat treated vessel.
From my college days I seem to remember these two techniques differ a bit in what they can find, however, everything I see with respect to coded pressure vessel construction just seems to regard them as surface crack detection techniques, is this right ?
Any help is appreciated
Thanks
Can anyone help me understand where ASME VIII Div 1 tells me how to select MPI or penetrant dye examination of welds on a non-heat treated vessel.
From my college days I seem to remember these two techniques differ a bit in what they can find, however, everything I see with respect to coded pressure vessel construction just seems to regard them as surface crack detection techniques, is this right ?
Any help is appreciated
Thanks





RE: MPI or Penetrant dye for ASME VIII
Steve
RE: MPI or Penetrant dye for ASME VIII
Yes, this is basically correct. The Code does not get into process detail requirements nor does it prefer one NDT method over another, when it comes to surface or volumetric test methods.
RE: MPI or Penetrant dye for ASME VIII
MT with suitable field strengths can find subsurface discontinuities but Code only views it for the purpose of locating surface discontinuities. PT can only locate surface discontinuities.
RE: MPI or Penetrant dye for ASME VIII
So if I have a non heat-treated vessel manufactured with materials that are not impact tested operating at ambient temperatures then I don't see anything in the code that compels me to use PT or MPI on the welds other than my own good practice.
Am I correct ?
RE: MPI or Penetrant dye for ASME VIII
RE: MPI or Penetrant dye for ASME VIII
My problem is that I just don't see in the code paragraphs where it says after welding that you must inspect with MPI or PT in the same way in does for x-ray and ultrasonic.
Thanks
RE: MPI or Penetrant dye for ASME VIII
RE: MPI or Penetrant dye for ASME VIII
RE: MPI or Penetrant dye for ASME VIII