incorrect von mises and max principal of simple lifting lug static analysis

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Hi folks, im new here and im also new at using CREO Simulate, havent really gotten the grabs of this p-element stuff yet.

To the point: I'm performing a static analysis of a lifting lug which is affected by a force acting on a surface inside a hole, this surface models the contact surface between the hole and the lifting tool. The lifting lug is constrained by bolts in holes and i've also constrained it to only move planar for a specified surface (see picture i attached).

I set the solver to MPA where i seartch for convergence of strain energy, von mises and maximal principal stress for the whole model. I set a convergence criteria to 7%.

The current mesh setup allows the solver to find a solution within the specified convergence criteria.. BUT in the "Run status report", in the last pass, it also stated that there are X-number of elements not converged..

The result give me both von mises and max principal stresses that are WAY above the value it should be. The area of interest is the bend and the hole section, stresses at the bolt holes are not of interest. The model material is S55, ive set modulus to 190 000 MPa and poisson to 0.3.

Does anyone have a any tip or tricks to get more accurate stresses? I've also attached the .prt file so that you can try the simulation yourself.

Cheers

1_forptc-prt-1.zip

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pkloninger(cust

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Hello,

example attached.

Regards

Paul

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1_forptc.zip

R

rcarnklev

Author

1-Visitor

Sorry Paul but i can't see where you attached example. First time on forum aswell

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rcarnklev

Author

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Never mind, it just did show on my mail Or profile, had to go on the forum page. Ty Paul!

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rcarnklev

Author

1-Visitor

Hi Steven,

I see, the way to achieve "real" convergence in PTC CREO simulate is quite hard. I haven't really learnt how to see if i get convergence or not, compared to H-elements.

I got some files from Paul which were very good but in his modified model the force from the lifting tool is modelled as a bearing force.. which im not really sure if thats true.. The lifting tool is a "hook" that will have a contact surface in the inner hole of ~84 mm^2. I've attached a part file which ive tried to model this more correctly but i get REALLY REALLY high stresses in the structure... the thickness and geometry of the plate should be able to handle this load according to the company.. the compoents of the force is setup to give a resultant in the direction of the sling. Please see the model