Does cutting pressure pipes (plate-welded pipes) also need to consider the rolling direction?
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For the blanking of pressure vessel cylinders, it is permissible to ignore the rolling direction when blanking. For pressure pipelines made from rolled sheet metal, does the rolling direction need to be considered? The pressure is not high. Is there a source? I just checked GB/T20801.4-2020 but couldn’t find it.
There is no need to consider the rolling direction, as the allowable stress already takes into account the mechanical differences in different directions.
Today, the rolling technology for steel plates is extremely advanced; containers are not even a concern, let alone pipes.
I think the same, but I can’t find any evidence! It was the first time I was feeding material into the pipeline, and some guy went straight to the boss and accused me of not feeding the material in the correct direction, which made everyone think I had done something wrong!
This post was last edited by In short_myP89 on 2021-9-7 at 13:59. It seems that many people have never been to a steel mill, and many have also forgotten what they learned in school textbooks. The resistance to edge tensile cracking and bending cracking along the rolling direction is much better than the formability perpendicular to the rolling direction, and this is more evident in cold rolling than in hot rolling. You can also ask the instructor in physical and chemical experiments about the differences between notches in impact specimens that are parallel to and perpendicular to the rolling direction of the material.
Where did you get this from? It must be quite old, right?
You haven’t participated in the promotion of the new standards these past two years, have you? Last year’s standard. HG/T 20584-2020 Technical Specifications for the Manufacturing of Steel Chemical Storage Vessels (effective as of April 1, 2021)
Ordinary carbon steel and stainless steel are fine; no need to worry about them. For special materials (zirconium, tantalum, titanium), it’s best not to use this approach
This is the metallography of Q235B. Design is inseparable from manufacturing processes; it’s useful to spend time reading more literature and research – there’s no end to learning.
Try your best, really try. Try my best. Do you stop driving after seeing an accident once? To generalize from a few examples.
Where did you find that article? Do some research on whether layered tearing is more likely to occur in thin plates or thick plates