Cylinder rolling pre-bending
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It has been found that in many manufacturers’ cases, there is no pre-bending on either side of the circular weld on the cylinder shell, resulting in large straight sections; after welding, these sections appear to be even flatter than the surface of a test plate. Does this have any impact on the strength of the weld when trying to form a perfect circle?
It has an impact; we didn’t perform pre-bending, and the weld cracked
There is definitely an impact, and the extent of that impact depends on the material of the cylinder
The impact is minimal; for our cylinder sheets, we generally roll them first, then weld them, and roll them again after welding.
It depends on the material, thickness, and width to determine whether to roll directly or pre-bend before rolling.
Whether pre-bending of the plate edge is necessary depends on factors such as the cylinder diameter, plate thickness, material, and welding method. Welding of thin-walled materials often results in significant deformation, and it is necessary to use a rolling machine to correct the shape after welding; as a result, the pre-bending step is sometimes omitted. Of course, post-weld straightening certainly has an impact on the properties of the weld and the base metal in the heat-affected zone; the greater the amount of straightening, the greater the impact on these properties.
It has an impact! As for the extent of the impact, it is related to factors such as the diameter of the tube section, the thickness of the steel plate, the degree of bending deformation, and whether preheating is applied.
There is definitely a significant impact; it is not recommended to weld the longitudinal seam without pre-bending both ends
It has little impact. Non-destructive testing should be carried out after re-shaping the part following welding completion.
To save trouble and reduce costs, the internal stresses, after being corrected again on-site, certainly have an impact on the weld quality; well, there’s nothing that can be done about it.