Joint Stiffness Calculation 1

[MintJulep]

It appears that most texts consider the case of a joint with two or more flanges bolted together with a nut on the far side. In this case, the flange compression cones used to calculate the joint stiffness appear to meet half way through the total thickness.

In the case of a single flange, with the bolt (technically it would be a screw) going into a tapped hole of the second member, do the two cones lie within the single flange?

 

[CoryPad]

Both cones don't lie within the flange, but they meet there. The cone in the tapped hole begins from the end of the screw thread, so extend it until it meets the cone from the screw head.

If you are going to do fastened joint analysis, I highly recommend VDI 2230. It has very illustrative diagrams for the questions you are asking. You can obtain this from Beuth:

http://www.beuth.de

Regards,

Cory

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

 

[MintJulep]

What do you use for the smaller diameter of the cone in the tapped part? Pitch diameter of the female thread?

 

[CoryPad]

That would work fine. Actually, VDI 2230 uses a substitutional model - they replace the small cone from a tapped thread joint with a sleeve.

Regards,

Cory

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