Disc Springs (Belleville Washers): Stacking & Applications

A disc spring — also called a Belleville washer — is a conical washer that is loaded axially. Pressed flat, it produces a very high force over a very short travel, which makes it the right choice wherever a large, predictable load has to be held in a compact space. This guide explains how a disc spring behaves, how the DIN 2093 dimension series are organised, how stacking changes force and travel, and where these springs are used.

How a disc spring works

Picture a shallow cone made from spring steel plate. When you press its two faces toward each other, the cone flattens and the material bends around its inner and outer edges. Because the deflection is small but the disc is stiff, the force is high relative to the travel — the opposite of a long coil spring. The load-versus-deflection curve is also non-linear: it rises steeply, passes through a region where the force is nearly constant, and can even turn over (the familiar snap-through region) depending on the height-to-thickness ratio. That shape is what lets a disc spring do jobs a coil spring cannot, such as holding a bolted joint under preload while staying almost flat.

DIN 2093 and the dimension series

The European standard DIN 2093 covers disc springs and defines the group 1, 2 and 3 dimension series. The groups separate the catalogue into size and force families so a designer can pick a standard disc by outer diameter, inner diameter and thickness, then read off the load at flat. Working to a standard series means the spring is a catalogue item rather than a one-off, which keeps cost and lead time down. When a standard disc does not fit, a custom disc can be made to the same principles.

Stacking: series and parallel

Disc springs are almost never used alone; they are stacked to tune the force and travel to the application. There are two basic arrangements:

In series (stacked face-to-face, alternating) — the travel adds up while the load stays the same as a single disc. This is how you get more stroke from a given pocket height.
In parallel (stacked in the same orientation) — the load adds up while the travel stays the same as a single disc. This is how you multiply force.

Real assemblies are usually a combination: groups in parallel for force, those groups placed in series for travel. Because friction between stacked discs adds hysteresis, the number of discs and the lubrication matter to the accuracy of the final curve.

Materials and heat treatment

Disc springs are made from spring steel plate and, like coil springs, are quenched and tempered. Alloy spring steels such as 60Si2Mn and 51CrV4 are widely used, and quenched and tempered spring steels are typically run in the range 40–50 HRC. Our heat-treatment equipment reaches a maximum temperature of 1,500 °C. Surface condition matters here too: decarburisation is checked, and safety-critical parts can be checked for cracks with magnetic particle inspection. For corrosive environments, coatings such as zinc-nickel, zinc flake or epoxy powder coating are common, and corrosion resistance can be evaluated by salt spray testing per ASTM B117.

Where disc springs are used

Their high force in a short travel makes disc springs a natural fit for bolted-joint preload, clutches and brakes, overload and safety devices, valve and bearing preload, and vibration-damping assemblies. Anywhere a designer needs a stiff, compact, load-bearing spring with a controlled curve, a disc stack is usually the answer.

Frequently asked questions

Q: What is the difference between a disc spring and a coil spring?
A: A disc spring gives high force over short travel and is very compact; a coil spring gives a roughly constant rate over much longer travel.

Q: What standard covers disc springs?
A: DIN 2093, which also defines the group 1, 2 and 3 dimension series.

Q: How do I get more travel?
A: Stack discs in series (alternating orientation) — travel adds, load stays the same as one disc.

Q: How do I get more force?
A: Stack discs in parallel (same orientation) — load adds, travel stays the same as one disc.

Q: What hardness are disc springs?
A: They are quenched and tempered spring steel, typically in the 40–50 HRC range.

Related resources

Need standard or custom disc springs, single or stacked? Send your dimensions and load to liu@chenjisprings.com or call / WhatsApp +86 158 5311 1612.