sheath in compression

[aidank]

have a circular plastic sheath that I am compressing at 3 points 120 degrees apart, sheath outer diameter 0.070in, inner diameter 0.040in, trying to figure out how I can calculate the displacement using equations, any bright ideas other than FEA analysis.

regards,
aidank

 

[GregLocock]

Yup. You described a curved beam, arc length 120 degrees, ends are encastre. Second year structures.

If howver the sheath is long in the axial direction then you need to solve the plate equation for the same 120 degree arc. That is third year stuff, and may not have a simple solution. In fact with a point load we can be sure it will have infinite deflection.





Cheers

Greg Locock

SIGlease see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[aidank]

only did Solids 1 in university remember seeing the picture of the chain hook in the book subjected to loading which is what you are on about I think, now to complicate things if these 3 loads were at 118, 123, 119 respectively do the arc angles just change

 

[GregLocock]

If you put your real world hat on then I think you'd agree that a 3 degree error is trivial in the context of the other assumptions you've made.

Yes, a crane hook is a good example.

Cheers

Greg Locock

SIGlease see FAQ731-376 for tips on how to make the best use of Eng-Tips.