Clarify "display" as it relates to IQI Essential Hole ASME V Article 2

[eybersb]

Can anyone clarify or define "display" as it relates to viewing the Essential Hole for an IQI as it relates to ASME Section V Article II Radiography?

We are currently having a dispute with our clients QC rep and our 3rd Party NDE company over which wire or hole can be seen on 2" Schedule 10S (0.109" wall) pipe welds shot to B31.3.

I see other threads discussing the best way to shoot these items (ie. ellipse), but our NDE contractor wants to stick with double wall, single view for better control of radiation and environmental factors (wind/vibration issues with greater stand off). Resulting shots with D3 film have had mixed results, but client rep consistently claims essential wire not clear enough. Reshots using hole type IQI are clearer to me, but I expect similar feedback from the client rep on the 2T holes, as some require use of a magnifying glass to see.

Any thoughts on what can reasonably cosidered "displayed"?

 

[rustbuster]

This is very subjective and eye sight / perception differs for everyone. I assume the RT conrtactor has annual vision tests. This may not hold true for the Rep.

Visual aids as in magnifying glasses are used fairly routinely the by "visually challanged" as I can vouch for.

The person interpretting and signing the NDE Report needs to ensure code compliance. If there is a discrepancy the acting level III should be engaged.

If the client rep is demanding more than the code then thay should cover the costs of any associated re-work.

Good luck

 

[eybersb]

Thanks for the feedback Rustbuster. As expected, client QC rejected latest films, although RT techs claim all necessary holes visible. I myself can see 8 of 10 necesary 2T holes. NDE contractor will be sending to their Level III for review, but I have asked them to also shoot the welds in question using elliptical technique in hopes of making this go away sooner.

 

[Duwe6]

This is a 'basic' problem with RT. Some people can see smaller changes in shades of grey than others. Thus they will be able to see the 'essential wire' or 2T hole when others cannot. Thus they can 'read' that RT acceptably when others cannot.

There are 2 problems with this. First is, how do you [the 'blind' guy] chect the interpretation of the weld in question? He can see OK and you cannot. I have not found an acceptable resolution to this one.

Second is that if anyone stares at shadows long and hard enough, they will see what they want to see. RT's are just a set of shadows cast by the item being inspected. I have run into several instances where the 2T-hole / 'essential' wire was imaginary. If you cannot see it in 2-seconds, you are imagining it. The problem in this one is deciding if they are imagining the 2-T hole, or are you the 'blind' guy and they can 'read' the RT film OK. I like to think that I can usually tell if this is the case, but I don't really know.

This is yet another reason that I strongly prefer UT to RT. If the tech can 'image' an irregularity on his screen, I can too.

 

[gtaw]

Anyone that can pass the annual visual acuity requirements of the applicable standard, i.e., ASNT SNT-TC-1A, CP-189, NAVSEA - TP271, etc. should be able to clearly see the essential hole or wire depending on the IQI type being used.

If there is a dispute whether the essential hole or wire can be seen, all those involved with reading the film should be able to produce their most recent annual visual acuity report. If they can't or will not produce an acuity report, they should be eliminated from the discussion.

Assuming all those involved can and do present their most recent annual visual acuity report, and there is one individual that still cannot see the essential hole or wire, then it isn't clearly visible.

At least that's my humble opinion on the subject.


Best regards - Al