Hi everyone,
I want to do a simulation in two steps. In the first step. In the first step, I apply a pretension to the screws, and in the second step, I apply a load, leaving the pretension fixed to the screws.
I am attaching the pmx file and the step file. I’m doing something wrong, I know, but I don’t know what.
Can you help me?
Thanks
You should create a boundary layer between two segments of the compound bolt part and apply the pre-tension load to that internal surface, not to the bolt shank.
Those tutorials show this:
Hi @FEAnalyst ,
Thanks for your answer, but I can’t finish the calculation
There must be some error in the configuration, but I don’t know how to proceed
any ideas?
Thanks
The bolts should be compound parts consisting of two halves with the pre-tension section (and a boundary layer) in the middle. Like in the tutorials linked above.
Hi,
I have corrected the model to apply the pretension on the screws, as you indicate. But I couldn’t solve
I attach information on how I have configured the contact. Is it possible that the error is there?
Thanks
Hi,
i modified your model and used a coarser linear mesh to speed up the analysis. See attached file for details.
anillos_mod.pmx (1.3 MB)
I can’t run it now. What’s the problem - just a generic non-convergence error ? In such cases it’s best to simplify the model (e.g. remove contact with the bottom part and make sure that bolts themselves are working as expected). Then you can add tie constraints or tied contact where needed and proceed to regular hard contact once it solves. But what you show there on those close-ups is quite nasty contact case and you may need to locally refine the mesh signficantly to get good results. The rest of the model would need a mesh refinement too but it should make sense to do it later.