Jam Nut locking device 1

[lockingdevice]

There are many discussions on the web about the Jam nut below a normal nut. I have read some good analyses, but what I want to have is a well engineered Jam locking analyze. I have read that this device is better resist against vibration. This is because the thread in the Jam nut will deform. If this is true, you will not have the bolt elongation you want to have. This will mean that you will not reach the utilized yield strength you want. If I want to lock a diesel engine in a ship I have to pay attention to vibrations. To alleviate the vibration forces, my bolt elongation has to be a certain length and I think the bolt will not have his elongation with a jam nut below a normal nut.
Or will this jam nut lock by compression and plastic deformation? And after this deformation is the Jam nut not straight but taps?

Can anybody help me with this issue?

 

[rmw]

The only time I have ever thought a jam nut was proper is in a situation where the first nut on the bolt is not tightened sufficiently against the bearing surface (if tightened at all) and a locking mechanism is needed to account for that and other means (wires, etc) were not available. I have used jam nuts numerous times, but never when I had a properly torqued first nut. To me, the jam nut in that case is tits (as in on a boar hog.)

rmw