Can high-pressure 316 pipes in imperial units and high-pressure 316 pipes in metric units be welded together and still pass flaw detection?
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Can high-pressure 316 pipes in imperial units and high-pressure 316 pipes in metric units be welded together and still pass flaw detection? Same pipe diameter
:lol 2 answers. . . Can it? Can’t it? . 1. For different nominal diameters, the outer diameter value can be either the same or significantly different. . For example, DN80 (88.9, 89) and DN100 (114.3, 108) yield different results; moreover, even with the same outer diameter, the wall thickness can vary. . Welded together without any special treatment, non-destructive testing may still yield failed results. 3. The non-destructive testing method you choose can also lead to different results. . You might fail RT, but you can pass PT. .
It’s sufficient for the inner diameters to be roughly the same, so no lack of fusion will occur. What’s left depends on the welder’s skills and the welding process
For the same outer diameter but different inner diameters, a three-fold wall thickness transition should be provided; for different outer and inner diameters, a transition section with a larger outer diameter and a smaller inner diameter should be fabricated. Such transition sections can generally be made from pipes with a higher wall thickness grade
The groove is given special treatment to ensure it passes the radiographic inspection
The inspection may pass, but it is not conducive to the operation of the pipeline; proper designs require transition splices