Take a look at these, they come in different tensions. You can stack them in various ways to get different pressures.
What is the definition of Belleville washer?
- A conical washer that can be stacked to create a powerful compression spring. The Belleville washer is often used to support applications with high loads and insufficient space for a coil spring.
- Belleville springs are a coned disk spring typically containing a hole in the center for a non-permanent fasteners (bolt et. al.). Bolt pretensioning is a typical use for a Belleville washer.
- Belleville springs can be nested (making springs in parallel) making more spring deflection for the same amount of load OR allowing higher loads with the same deflection - depending on their orientation. While useful, nesting Belleville springs can be unstable.
- With proper design (selection), Belleville springs can be used for a "snap-acting" mechanism. Likewise, with proper design/selection, the spring can have constant force over a large deflection. This type of design maintains bolt pretension when a dynamic load is present or in situation where thermal expansion/contraction is significant.
Cite: Shigley, Joseph et. al. "Mechanical Engineering Design" 7th International Edition. 2004.
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