Simulating Bolts in Analysis
Simulating Bolts in Analysis
(OP)
Hi everyone,
Can anyone give any guidance in simulating bolts within an FEA analysis?
I have seen some FEA reports of brackets bolted to stiff structures(ship/train walls),where instead of modelling the wall structure and bolts, they have simply included the bracket and assigned a fixed restraint on the inner surface of the hole in the bracket the bolt would pass through. I would have thought defining a split line around the hole, the diameter of the bolt/washer, would have been more appropriate.
Anyway I just wanted to gauge what othe people did
Many Thanks
Tom
Can anyone give any guidance in simulating bolts within an FEA analysis?
I have seen some FEA reports of brackets bolted to stiff structures(ship/train walls),where instead of modelling the wall structure and bolts, they have simply included the bracket and assigned a fixed restraint on the inner surface of the hole in the bracket the bolt would pass through. I would have thought defining a split line around the hole, the diameter of the bolt/washer, would have been more appropriate.
Anyway I just wanted to gauge what othe people did
Many Thanks
Tom





RE: Simulating Bolts in Analysis
Most of the work I do deals with preloaded bearing stacks or bolted flanges so typically the bolts or retaining elements are modeled and preloaded. However, in many cases I will simply fix the ID of a bolt hole if I only am concerned about the impact on the structures stiffness being constrained by the bolt rather than stresses in that regions.
This topic really isn't that complex and really is dependent on what you want to get out of your analysis. Use your best judgement.
Good luck!
RE: Simulating Bolts in Analysis
RE: Simulating Bolts in Analysis
Cheers
Greg Locock
SIG:Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.
RE: Simulating Bolts in Analysis
It all depends on how far you want to go, or need to go, in modelling the bolt.
corus
RE: Simulating Bolts in Analysis
Ed Danzer
www.danzcoinc.com
www.dehyds.com
RE: Simulating Bolts in Analysis
The following might be a useful reference for you.
Method of Modeling Bolts in the Bolted Joint by Jerome Montgomery.
MrVessels
RE: Simulating Bolts in Analysis
Thank you very informative
Tom
RE: Simulating Bolts in Analysis
I would stick with hand calculations for the fasteners and then testing if the joints/loading in question is complicated.
There are many factors to consider that you may or may not capture in your model, it will only be as good as your assumptions. Unless you know all the details (environment, loads variations, bolt quality, etc.) you will need to ensure a reasonable factor of safety is built in. At that point, the benefit of detailed FEA is probably lost for a "standard" joint /bolt.
Also see: http://www.boltscience.com
Batman2