Bolt preload in NX 8.5
Bolt preload in NX 8.5
(OP)
Has anyone used NX 8.5 for bolt preload? NX 8.5 models the bolt as solid element-anyone has experience using this functionality? Any video/tutorial for this will be very useful
Christy
Christy





RE: Bolt preload in NX 8.5
I use NX8.5
HP Z600 Intel Xeon E5520 2.27GHz Dual
Quadro FX 3800 5GB
9GB Memory
Windows 7, 64-bit
Groeten, Michel
www.kvi.nl A leading Dutch institute in atomic and subatomic physics
RE: Bolt preload in NX 8.5
Quando Omni Flunkus Moritati
RE: Bolt preload in NX 8.5
RE: Bolt preload in NX 8.5
Then assign a cross section and material to the CBAR or CBEAM 1D element which represents the bolt shaft.
And in your sim file you can easily add a 'bolt pre-load' with 'load type'. Select the CBAR or CBEAM elements and add a pre-load.
I use NX8.5
HP Z600 Intel Xeon E5520 2.27GHz Dual
Quadro FX 3800 5GB
9GB Memory
Windows 7, 64-bit
Groeten, Michel
www.kvi.nl A leading Dutch institute in atomic and subatomic physics
RE: Bolt preload in NX 8.5
RE: Bolt preload in NX 8.5
RE: Bolt preload in NX 8.5
http://lace.uni-mb.si/strojni_elementi_1_UNI/sliko...
pages 24 and 25 (of the 50page pdf) here.
the first image on the 24 is the ideal, the second two are the actual scenario. on the pg. 25 there are more pics of how the preload is determined by the flange design... (look for the Kf)
also, how do you call that in english - where the preload starts, from the Kf factor (just look for it in the eqs)
RE: Bolt preload in NX 8.5
RE: Bolt preload in NX 8.5
Anyway, the load distribution in a bolt connection is dependent on the stiffness ratio of the bolt vs. the clamped area. If you model this correctly, the FE model should take care of the stiffness distribution and ditribute this correctly and thus the load introduction plane (and Kf) is taken care of. But remember: The FE method is a numerical approximation approach, and the only thing you can be 100% sure of is that the answer is wrong!! How wrong depends on the skills of the FE user (and to a very minor extent the SW system used)
Sorry for sounding very pessimistic, but in general I sometimes get scared of engineers relying 100% on the FE answers. But if the analysis is done correctly, your answers will be reliable, and probably good enough.