SImulate Helical threads in axisymmetric model?

[Dnov]

Hello Everyone,

I am currently modeling a pipe connection in which there are helical threads on both the pin and coupling. Due to the extensive computational cost of running this model in 3D, I have created an axisymmetric model.
I am simulating make-up of the connection by using the SHRINK parameter in *CONTACT INTERFERENCE, but now I want to simulate two consecutive make-ups with different torque levels.
Since this is axisymmetric, applying torque will merely rotate the instances without introducing any additional stresses, how can I simulate this while still keeping the model axisymmetric?

Any help would be greatly appreciated,
Dnov

 

[DanStro]

One of the example files is of a pipe thread connection. I believe they use convert the torque into a in-plane preload.

HTH,
Dan

Han primo incensus

 

[Dnov]

Thank you for the reply DanStro,

I have looked at the example you are refering to (1.1.20 example problem manual?), and cannot see any preloading.

My model is set up almost identical to the way they have, although they do not have the problem of having to perform two consecutive makeups.

The way I am simulating multiple torques is by changing the thread cross section of the coupling instance, this additional overclosure results in a higher contact area/stress and therefore gives me a higher value for CTRQ, as desired.

The only problem is that since i am changing the cross section of the coupling it must be performed in two separate analyses. And since i want the residual strains from the first make-up this is causing an issue.

Could you please clarify on what you mean by 'converting the torque into an in-plane preload'?

Thanks again for your reply,
Dnov

 

[LOUETRI]

Hallo,
I am trying to model a silo in abaqus in 3D,and I want to aplicate a geometric imperfection,how can I do it