N/A Regulator belleville stacking question

#1 reg stack. (()) (()) (()) (())

#2 reg stack. ) (()) (()) (()) (())

How can adding a single washer to a double stack reg increase the max pressure? Would it not simply limit the max piston travel by the thickness of one washer?
It adds additional stiffness at the same time. Just like if you removed one from #1 regulator stack (less tension), lower max pressure.
 
According to the Belleville disc regulator operating manuals I have for pneumatic systems, you adjust the linearity of a belleville disc regulator by the thickness of the disc whose orientation is concave side towards the piston head.

Belleville disc regulators are NOT designed to operate throttled open during system operation. They are an "on/off" mechanical device.

In your stack #2, the disc you added in the orientation you added it , if it is next to the piston head, will allow the regulator to open more gradually as the d/p across the stack increases.

An engineer would need to know the material, thickness, and degree of cone of each disk to calculate the the total "spring" force difference between stack #1 and #2 due to the addition.

Mr. Ernest Rowe has experimented with different belleville disc thicknesses and orientations to find the best stack for Regulator #2 on an M3 Impact.

The last stack I knew he had implemented, used 3 different thicknesses and the first disc is orientated concave side towards the piston and the last disc concave side towards the seat to allow for a more precise linear operation.
 
Last edited:
  • Like
Reactions: Impact701
) (()) (()) (()) (())
You're right...the single washer on the end will act like a shim (flat washer). The predominant spring rate is dictated by the nested pairs (( , which you can think of as single thick washers that are much harder to compress.

By the time the nested pairs compress by any meaningful amount, the single washer on the end will have squeezed flat.
 
  • Like
Reactions: Impact701
This is the washer stack that Ernest Rowe was selling on ebay.
You can see the different thickness of the washers.
He said they are for 100 to 200 bar

))()()()()((

20250220_194743.jpg
 
Last edited:
I could understand if you flipped it, as

((()) (()) (()) (())

But the other way it simply goes flat before the double stack come into play?
Exactly ... if all others are doubles .... a SINGLE does most of the flexing and controlling, until such time it goes nearly flat & progression of the doubles takes over.
 
I always figured that some manufactures used different thicknesses to hit a certain max pressure, not feally for any progressive spring action.
Actually the bevels are COUNTED ON to have a progressive nature, for seat to open and close with sorta low pressure losses of the plenum side the spring stack must have a Progressive / Elastic property to it.
* Too few of bevels, triple stacks or greater, either/or looses this progressiveness property and regs only want to react with larger swings in pressure loss within plenum. Likely why HILL chooses to use Coil springs in there Regs ???
 
  • Like
Reactions: DesertSilver
I have recently gone through adjusting the Bellville washer in a cheap Aliexpress 1800PSI regulator.
I wanted to raise the output pressure in the 2500-2700 PSI range.
It took 6-7 trials to get it there by reorganizing the washers.

In the end I went back to the washer stack configuration for 1800PSI and added an extra washer which became a shim.

To raise the pressure just use thin shims

On a second 1800PSI regulator I just used very thin washers to raise the pressure.
Measure the OD/ID of your Belleville washers and buy thin washers with the same OD/ID.

I bought these thin shims:
M8x16 50pcs, 0.1mm Thickness
 
Actually the bevels are COUNTED ON to have a progressive nature, for seat to open and close with sorta low pressure losses of the plenum side the spring stack must have a Progressive / Elastic property to it.
* Too few of bevels, triple stacks or greater, either/or looses this progressiveness property and regs only want to react with larger swings in pressure loss within plenum. Likely why HILL chooses to use Coil springs in there Regs ???
Excellent point. FX was simply adding one or two extra Belvilles in the alternating configurations to achieve a stiffer stack. I'm pretty sure that FX doesn't sort their washers which is what I did but in-order to get the thickest it takes a bunch of them, the standard packages I was buying they followed a bell curve. I like the idea of shims but I'd still attempt to equal out the washers so the all work the same. I'll bet it'll still only be a 50 bar range.