Thanks for the pointers! The 2nd one looks promising.
Did not find any (for me) useful help there.
I am sure there must be someone out there who knows a lot about this.
Hoping, hoping ... ;-)
We have a steel tube made of a material with yield limit 1000 N/mm2.
It is 250 mm long, outside diam. is 76 mm, inside diam. is 60 mm.
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