Calculating Torque required for twisting a tube?

[kennykmk]

Hi everyone! I was wondering if I could get some direction with calculating torsion.

I have an open ended Tube made from biomedical grade Nylon and I need to figure out how much torque I will need to apply to twist the tube. The Tube has a wall thickness of .9mm and an outside diameter of 40mm. I have physical results but would like to compare them to theoretical results. Can somebody help?

Thanks,

Kenny

 

[patprimmer]

Certainly not with the information supplied, and probably not in any case.

At least a type of nylon and moisture conditioning status is required to even begin to think about it.

There are quite a few very different types of nylon suitable for biomedical. Most likely are type 6.6, type 11 and type 12.

They will have up to 300% difference in flex mod depending on if they have been in water or extremely dry environment for some time prior to testing.

Regards
Pat
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