Issues with pipeline welding inspection?
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Question: 1. Is the weld from socket welding considered a fillet weld? How should the proportion of radiographic inspection for such welds be determined? (Assuming it is the SHB category) 2. Is it absolutely impossible to perform radiographic testing on fillet welds? What methods are generally used? 3. Can ultrasound replace radiographic testing?
1. The welds from socket welding are considered fillet welds, and the proportion of radiographic testing for these welds is determined in accordance with standards and design documents. 2. Fillet welds generally cannot be inspected using radiographic testing in engineering applications at present. Although there are already relatively advanced techniques for radiographic inspection of fillet welds, they have not yet been widely adopted. 3. Ultrasonic testing can sometimes replace radiographic testing; it is used in specific situations. Ultrasonic methods are not sensitive to cracks in the same way as X-rays, and they are generally applied to plates with a thickness of 8 mm or more, while it becomes more difficult to use X-rays for plates with a thickness of 40 mm or more. For the containers just manufactured, which are sensitive to certain types of cracks, both X-ray and ultrasonic inspection are required. 2. Ultrasonic testing is sensitive to cracks, whereas X-ray testing is not
The welds produced by socket welding are definitely considered fillet welds, and fillet welds are generally inspected using magnetic particle or penetrant testing, with the same proportion as that used for radiographic testing. Replacing ray inspection with ultrasound requires design approval.
For fillet welds, RT testing is generally not possible; the method we use in our work is usually PT, with a ratio that corresponds to that of RT testing for the same type of pipes.