X-ray examination scope
X-ray examination scope
(OP)
Hi all,
I am recieving from the engineering company some data confusing to me. For a carbon steel pipe with approx. 100°C op. temp. and 300#, in some cases we have to do 100% radiography to the welds and in other cases only 33%, in prefabrication.
I have check the code (344.5 of B31.3, which applies), and it seems that this is not necessary, although it is not clearly enough to me.
So the question is: when is mandatory to perform 100% radiography to a welding union of pipes or pipes and accesories?
Advanced thanks
samuelo
I am recieving from the engineering company some data confusing to me. For a carbon steel pipe with approx. 100°C op. temp. and 300#, in some cases we have to do 100% radiography to the welds and in other cases only 33%, in prefabrication.
I have check the code (344.5 of B31.3, which applies), and it seems that this is not necessary, although it is not clearly enough to me.
So the question is: when is mandatory to perform 100% radiography to a welding union of pipes or pipes and accesories?
Advanced thanks
samuelo





RE: X-ray examination scope
I reviewed ASME B31.3, Section 345.5. It seems clear to me regarding RT of girth and miter groove welds. Also referenced in this section is random RT and spot RT.
The Engineer involved with the design of this project has final say above and beyond minimum Code requirements for nondestructive testing.
RE: X-ray examination scope
RE: X-ray examination scope
May be because the fluid is hazardous, i think that a inspection of 100% radiography in welds can be with some product like H2S e.g.
Usually in refineries the lines with H2S are made in carbon steel with TT, so you must radiography all the welds before (or not is your problem) TT and post ever.
It´s only my opinion
RE: X-ray examination scope
I don't see the point in making radiographys to lines handling non hazardous fluids, but if a girth weld is not well done, then there can be problems with corrosion cracking, and hence the 100% radiographs.
Thanks for your valuable answers.
samuelo
RE: X-ray examination scope
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RE: X-ray examination scope
As metengr has stated--the design engineer can specify requirements that exceeed Code requirements.
The welders in the fab shop are considered experienced and thoroughly tested by their employer. If a bad weld is detected in the fab shop then the examiner will review other welds by the welder in question.
The available pool of field personnel may be considered sub-par or not as experienced in a local job market depending on the site location. If a welder hired at the job site successfully completes a weld coupon does not necessarily mean that his next weld will suffice. Some construction jobs have a high turnover rate hence, weld consistency is an issue.
RE: X-ray examination scope
http://virtualpipeline.spaces.msn.com