What this calculator does
A disc spring, or Belleville washer, is a shallow conical washer that produces high force at small deflection. Stacks in series add deflection; stacks in parallel add load. The calculator reports the force–deflection curve and checks the stress at the inner and outer edges.
Inputs and outputs
Inputs
- Outside diameter and inside diameter
- Thickness
- Cone height
- Working deflection
- Stack arrangement
- Material
Results
- Load at the working deflection
- Stiffness
- Edge stresses
- Flat load
- Stack load and travel
Typical applications
- Bolted joints
- Valve spring packs
- Clutches
- Bearing preload
- Overload protection
Design notes
Disc springs are strongly non-linear: the load peaks and then falls as the disc approaches flat. Specify the working point on the curve rather than only the flat load, and define the stack arrangement because it changes both load and travel.
The interactive calculator interface is currently in Chinese. Enter your values there, or send us the load, travel and space constraints and our engineers will return a checked calculation sheet in English.
Frequently asked questions
What is the difference between series and parallel stacks?
In series, discs are stacked in the same direction, so travel adds and load stays the same. In parallel, discs are stacked face to face, so load adds and travel stays the same.
Why is the curve non-linear?
The conical geometry changes the leverage as the disc flattens, so stiffness rises and then falls. This behaviour is useful for snap-action and overload protection.
Do you supply standard sizes?
Yes. Common metric disc spring sizes are available, and non-standard diameters, thicknesses and materials can be produced to drawing.
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Need this spring manufactured?
Send a drawing, a sample or the parameters from this calculator. We will review manufacturability and reply with a quote and a sample lead time.