FEA Force vs. Pin Constraint.

[204Е10]

Hi every one:

My question is when I create a part and I constraint with a Pin constraint and aplicate a force in the opposite direction why there are not stress around the hole but I have stress if I replace this pin constraint for a force in the opposite direction how it should be.

Please se the pic I have attached.

Cheers.

[swalton]

I think that the issue is as follows:

The pin constraint locks the surface of the hole in all of the radial directions.  Each element node is prevented from moving, so it they don't develop any strain.

The bearing load applies force to half of the hole, in the load direction.  That means the unloaded side of the hole is free to move and develop strain in order to resist the load.

Pin constraints are not very useful if you are trying to evaluate the strain response of the material around a hole.  

[204Е10 · Accepted solution]

Ok thanks I think is misleading call this constraint Pin because it doesn't behave like pin. Also I have created a assembly with the proper pin and separation constraint and it has a different behaviour that even with the two forces, are there any answer for this kind of behave? (a image is attached)

Cheers.

[infoEHE7X]

Never use that pin constraint (it's use is for single parts pivoting around a joint assuming no radial movement at all). Instead make a round bar and put it in the hole then use sliding/no separation contact. It works as a pin constraint.