Some codes (ASME Boiler and Pressure Vessel Code for example) specify criteria for both relevant indications and rejectable indications. If on a RT inspection you detect indications which are large enough to meet the relevant criteria, but small enough to be within the limits of aceptability, then it would not be right to write NO INDICATION on the report. The relevant indication shall be measured and reported as such.
This also serves a purpose later on, during the service life of the part, if other inspections are carried out, having results to compare with and not to be speculatng if the indications present developed in service.
As always I hope this helps.
16:58 Mar-02-2009 Michel Couture NDT Inspector, , consultant, Canada, Joined Sep 2006 476
I totally agree with you all and to add to what Juan talked about, I was in the same situation i.e. inspection of pressure vessel and we used to indicate on our report even the UT signals that was caused by geometry. I also know from experience the practice is also similar in the nuclear industry. And again like Juan said, it will help in doing the assesment and also establish a trend during futur inspection.
In the end, we as NDT technician have to remember, that we are working for our customer. Having said that, I don't mean to agree to falsify a report when you know that it doesn't meet code, but when a customer wants to see a specific wording or want you to reject a part although the indication is within codes, HEY!!! who are we to say no?
I do agree with you Michel. The only exception in my opinion would be that if an indication is relevant but acceptable per acceptance standard then NO INDICATION would not be acceptable wording on report. I think it would be wrong for someone to request such a thing.
I guess I brought about some confusion. By all mean, if there is an indication, it should be mentionned. I wouldn't have any other way. What I meant was when an indication is acceptable by code and the customer still wants it rejected. Then I do what they ask. If they want to be more stricked than code, that is their prerogative. Let remember that after all, codes are the minimum. Now is it reasonable? Well that is another story.
Cheerio's to all
21:09 Mar-02-2009 S.Senthilkumar Engineering, QA/QC/NDT, NOV (National Oilwell Varco), Angola, Joined Mar 2006 35
Thank you for your contribution. One more clarification. For example ASME SEC VIII RT, UT, MT & PT says
NON Relevant Indicattion Sizes>
RT less than 0.75mm (Appdx for Rounded Indication)
MT less than 1.5mm (Art ...)
PT less than 1.5mm (Art..)
UT Only says 20% Reference level above evaluation.
All the above are says non relevant indication, So I need to record in report less this size as well?
04:15 Mar-03-2009 Juan Amado Engineering, Inspection , Arco Industrial, S.A., Panama, Joined Nov 2001 43
I'll add the following regarding how I understand it:
1. If there are no indications (which is very rare, but does happen), then you can say: NO INDICATIONS WERE OBSERVED
2. If there are indications, but are smaller than the relevant indication size, then you can say: NO RELEVANT INDICATIONS WERE DETECTED
3. If there are indications that are, larger than the relevant indication size, but smaller than the rejectable indication size, then you can say (for example): "A rounded indication was observed measuring xx in its largest dimention", and the weld or joint or part, as appropriate, should be marked accepted per the applied criteria.
4. If there are indications that are larger than the acceptable indication size, then it shall be reported, and marked as rejected.
Normally, all recordable indications are to be specified in NDE report. This is depending on the requirements of the standard or code you applied.
For example, in UT testing, you found some spot indications in testing(maybe small porosity, slag), but their amplitude is lower than DAC-10 dB. The standard you applied has already specified that all indications with an amplitude lower than DAC-10 is regardless except they could be evaluated to hazadous discontinuities such as crack, LOF etc. you can say, "No recordable indications are found." Otherwise, you should report every recordable indications in the sheet.