Belleville washers-which way to apply?

J_J · Feb 4, 2011

When stacking washers, do you put every other one upside down? If you use only two, is one of them upside down?

I found the answer. There is more than one way to install these washers.

http://www.solonmfg.com/springs/features.cfm

CurlyDave · Feb 4, 2011

If you have four nuts and four Bellevilles, it really doesn't matter which way they go on. They will provide the same spring force in either direction. I would put the smaller bearing diameter against the harder metal.

Now if you have more than one per stud, you need an assembly drawing to get it right.

As J_J points out they can be stacked in all sorts of different ways in various applications. The original design engineer selected a certain stack for a reason.

nickel plate · Feb 4, 2011

Here is the makeup of the hydraulic stack:
first set of remotes 1-1/8" thick steel
second set of remotes 1-1/8" thick steel
Woods BH90-X outer cap 1" thick aluminum
four M8 threaded studs (one at each corner of the stack)
four M8 Belleville spring washers
four M8 nut torque nuts to 24 N-m (18 ft-lbs)

jonyyuma · Feb 4, 2011

FastPauly said:
We used them as Baby Grand states....in high temperature applications. On rotary tube furnaces, the tube flange bolts can break if the washers are not used. There is a tremendous amount of force applied to the fastener from the effects of thermal expansion....to the point where thread damage occurs (stretching) or complete failure (breaking). Although somewhat expensive, the use of them greatly reduced the time involved in removal of the bolts....stretched threads are a PITA to deal with. A torch was often used to remove the damaged bolts....which often resulted in damage to the flange faces.

And yes...the cone goes towards the fastener ends.

The thermal expansion is the reason our Hi-voltage gear has them on the buss bars. We have never had a failure of a bell washer as the torque rating is important.I have been installing them since the 80's and maintain them now, which is a simple tor. check. Vibration is not a factor here..Jy.

Mace Canute · Feb 5, 2011

CurlyDave said:
If you have four nuts and four Bellevilles, it really doesn't matter which way they go on. They will provide the same spring force in either direction.

Dave, I don't believe that is correct. That would be the case if the nut was large enough to cover the outside edge of the washer, but I haven't seen that to be the case with any belleville washer I have used. When the washer is upside down, only a small portion of the spring material is in use, that which the nut covers and it then acts like a regular flat washer.