Technical Discussions: Sizing Defects

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Sizing Defects
Posted by: General , E-mail: iclampers@hotmail.com, on November 30, 2004 at 01:07 :
When sizing a defect according to ASME you take the maximum amplitude and then get the length ccording to the 6 db drop. But according to ASME it has to be over DAC and a certain length to be rejectable, so I have a question about determing length.
Do you only consider the signal portion for length if it goes over DAC, ie; I maximize on my signal and it is over DAC (but not by much), I move laterally to determine length by 6 db drop but before I get to the 6db drop location the signal is now below DAC. SO do you only consider the part of the indication that goes above DAC for determining length or is it 6db drop regardless?
If I size by the 6db drop it may exceed length by code and be rejectable but if i size with the portion that is above DAC it may be acceptable. I can see arguments for both ways.
What is the correct way?

Follow Ups:

Re: Sizing Defects charlie jackson 15:04 Nov-30-2004 (0)

Re: Sizing Defects Dent McIntyre 13:59 Nov-30-2004 (1)

Re: Sizing Defects General 12:47 Dec-01-2004 (0)

Re: Sizing Defects Chris Jones 07:46 Nov-30-2004 (0)

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----------- Start Original Message ----------- : When sizing a defect according to ASME you take the maximum amplitude and then get the length ccording to the 6 db drop. But according to ASME it has to be over DAC and a certain length to be rejectable, so I have a question about determing length. : Do you only consider the signal portion for length if it goes over DAC, ie; I maximize on my signal and it is over DAC (but not by much), I move laterally to determine length by 6 db drop but before I get to the 6db drop location the signal is now below DAC. SO do you only consider the part of the indication that goes above DAC for determining length or is it 6db drop regardless? : If I size by the 6db drop it may exceed length by code and be rejectable but if i size with the portion that is above DAC it may be acceptable. I can see arguments for both ways. : What is the correct way? ------------ End Original Message ------------

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