API 650 8.1.2.8 says
"Each radiograph shall clearly show a minimum of 150 mm (6 in.) of weld length. "
The film used by RT crew is 240 mm.
Who decides which 150mm is to be interpreted if a defect is found on one or the other ends but could have more than 150mm of defect free weld at the other end of the shot? Or can I evaluate anything that shows up in the 240mm? My take on this (me being the TPI/eyes of the engineer and owner) is that what shows on the film is subject to be accepted or rejected whether there be 151 mm of continuous "clean" weld or something rejectable rears its ugly face at 237mm. If they wanted to, they could have chopped the film off shorter.
The never ending war between contractor and owner continues...
FWIW, this issue has not arisen yet, but the "Evil Eye"/"Unemployment Truck" is coming tomorrow, and a couple of the welders just aren't that slick of hands.
Using the word evaluate in this context is concerning to me. In my eyes, a third party is not there to accept or reject anything, only report what they see, or don't see, to those who have contracted them. If you see what would be a rejectable indication anywhere on the film, but the RT crew writes a passing report, that is something the owner needs to know. Conversely, if they write a reject, and no rejectable indication exist, that is something they need to know as well. That is where it should rightfully end.
If a person has authority, qualification, and certification to unilaterally reject any given item, then they are not a third party, but either a direct representative of the owner, or a direct representative of the contractor. If that same person rejects a radiograph, but does not hold a certification for RT interpretation under a program that is recognized on that particular project, then they are setting themselves up for a fall.
Regarding a reject, irrespective of the above, I would not want to explain to anyone why I let a rejectable indication go that was clearly visible on the film. The code states "minimum", therefore anything that shows up in the film is fair game.
My opinion for what it's worth.
Thanks for the responses CWI555 and dbigkahuna. I was hoping to receive a verification on "the minimum".
My colleague is on the pipeline side of the project and has a Radiographic Interpretation cert of some sort (I dunno for sure, cuz he's Scottish and can't speak very good English. lol) and can make the call. All I know is that I get paid on time and the math is right.
I am crotch deep in dealing with a new code, yet managing to have a killer time doing it.
I agree with CWI555.
Another tips : If RI is not your expertise and wanted to act busy viewing the radiographs, another killer time is to trace the weld profile and compare it against the actual weld joints tested. Pay more attention on those joint locations not easy to shoot. You'll be more famous once you caught the RT crew cheating.
~Joey~
The weld is interpreted from the center of the film regardless of the film length. If the tank erector is paying for the film you will butt heads but as the rep for the tank owner if something is observed on the film you can order additional radiographs.
But you (tank owner) will have to pay for them. If the tank erector has its own radiograph crew, you may have to bring in your own crew. And if they are jack a$$e$ they may pull scaffolding on you. And if the little darlins play that game, well you have the crew for a minimum, they have film, well lets see what you are hiding.
Unless you have a old time tankee supt., the new ones don't have the stones to pull this any more.
The locations of the film are pretty much set by 650 except for the random on the horiz.
Worked with one inspector where the supt wanted to play some reindeer games. Contractor showed up at 7 am and the xray crews had been there since Midnight. They shot the whole tub to second and 100% on the verts in the first course. Really bad welding. They wound up gouging out ALL the welds and re-welding. But the inspector was backed up by the owners engineer and PM. Next morning there was a new crew on the job.
But remember, unless you are a Level II, you cannot interpret the film. You can qualify the film, but you cannot read it. If you bring up you looked at the film and saw whatever, they will hand you your head. Let the Level II call it. If you see something, have the crew shoot another shot with the anomaly centered in the next shot, but do not ever call it. Unless you have that ASNT Level II leave it alone.
When we would submit a procedure for spot radiography, it specified that the location markers (in most cases "A" and "B") would be 6" apart, and that is the area of interest. The film is a standard 4.5" X 10" so there is additional weld shown outside the area of interest. The 6" area is interpreted, and those results are recorded on the reader sheet.
So, if a questionable or rejectable discontinuity shows up outside the area of interest it technically could be ignored however a responsible Level II or III, owner, AI, or a third party surveillance inspector would most likely comment on this. And a responsible fabricator will usually opt to repair that area. Right or wrong, I have seen thousands of repairs made in this situation.
This is what is being passed off for "acceptable radiography"! How could any self respecting shooter or Level II let this get out of the dark room, let alone allow it to get to my desk? Looks like a bunch of fingernail clippings on the film.
Between the language barrier and cultural norms, some times this expat thing can be a major PAIN!
You are correct, artifacts in the area of interest are cause for a "reshoot". The dark marks in your radiograph are caused from bending and pressure. The thinner crescent marks are usually caused when the film is flexed when going on the developing reels. It looks like they are using 70mm film? This happens more often on the first piece of film on the reel (the starter piece),... as more films are added they go on easier because the reel gets progressively larger.
A simple fix is to add a "cheater" to the developing reel. Ask those technicians to process about 12" of green film. When it comes out of the dryer they will have a clear (light blue) piece of film. This is the cheater and goes on the reel first. Now when they add newly exposed negatives they won't fight to get that first piece on. They should have a cheater for each developing reel in the darkroom.
I agree with Thirdeye. The film should be rejected. No artifacts in the area of interest.
What is the density of the film? I take a reading at 0, 6 and the essential wire. All have to be between 2-4. They do have a densitometer?
And if that is 70mm film, it is the wrong size.
