Press fit

[Juliana]

Hello,

I am trying to find the pressure distribution at the contact surface of a press fit assembly.
How can I model the press fit?

Thanks
J

 

[mloew]

Juliana,

It is simple, but you can not perform this analysis yet in integrated mode. You must use the stand-alone version of Pro/MECHANICA.

If you are a maintenance paying customer, you can access the following document from the Technical Support Knowledge Base (

http://www.ptc.com/appserver/cs/search/kdb.jsp):

Suggested Technique for Modeling Press-Fit Contact Analyses (

http://www.ptc.com/cs/cs_23/howto/mst1293/mst1293.htm)

The basic technique is to model the initial interference so that the two bodies overlap and then use a contact surface for the two surfaces that will eventually be coincident. You will need a load to make an analysis valid, so if there are no other loads, use a dummy zero Global temperature load.



Best regards,

Matthew Ian Loew
"Luck is the residue of design."
Branch Rickey

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

 

[cnuk]

I've put in an enhancement request to be able to do this in integrated mode. When I checked today it's status was listed as "Pending". I don't know what that means unfortunately. Maybe in Wildfire 4

 

[PistonRod]

An easier method to be used in Integrated mode is this;

If you know the interference (displacement) of the press fit then you can work backwards by placing a pressure load on the female section until the interference displaecement is reached. This value of pressure can be assumed to be the press fit pressure.

 

[ksarita]

hi piston rod,

i am also stuck with interference fit contact analysis. And i liked the method that you have mentioned. but can you explain me with an example. please. i am desperate to know. thanks
Sari

 

[Heckler]

Why not just create a spreedsheet that calculates hoop stress based on tolerances and temperatures.

Best Regards,

Heckler
Sr. Mechanical Engineer
SW2005 SP 5.0 & Pro/E 2001
Dell Precision 370
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"Coming together is a beginning, staying together is progress, and working together is success." - Henry Ford

 

[mloew]

Heckler,

Performing closed form calculations is always a good idea. However, it will only work for geometry that has the stresses calculated from closed form equations. I have performed several press-fit calculations on irregular geometry. Using a FEM based solution was the only way to model the problem with accuracy.

Best regards,

Matthew Ian Loew


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