Can the Class A and Class B weld joints in the main body of tank containers all be inspected after welding is completed?
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As the title suggests, ordinary tank inner containers generally have few components inside, and people can enter them. During the manufacturing process, can welding of Type A and Type B weld joints be completed first, followed by non-destructive testing? Regular size inspections will be carried out during the process.
There is no standard requiring that the longitudinal seams of the tube sections be inspected before the circumferential welds are welded; it is acceptable to inspect all both longitudinal and circumferential welds together after they have all been completed. In the case of spherical storage tanks, inspections are generally carried out after all the welds have been finished. However, as a standard cylindrical vessel, there are many advantages to performing the circumferential weld assembly after the longitudinal weld welding inspection has been passed. Such as: correction of welding deformation in longitudinal welds, control of welding quality at the ends of longitudinal welds, welding test plates, and many other aspects.
Theoretically, non-destructive testing can only be carried out after all longitudinal ring welds have been welded.
First, during routine radiographic inspection of containers, circumferential machines are used for ring seams, while directional machines are used for longitudinal seams; conducting inspections on both types at the same time is rather complicated. Second, some equipment requires the preparation of product test plates, which must be inspected along with the cylinder before they can be cut away. Third, if there are defects in the weld, it is easier to handle them by conducting inspections on the longitudinal and circumferential seams separately; however, once all welding is complete, if defects exist, it is more complicated to carry out lifting and repair operations compared to inspecting them separately. I haven’t worked on large-scale equipment, so I’m not familiar with it.
Could you explain the reason or source?
No, I made that up. I think the analysis on floor 5 is very good.