What is a Belleville Washer?
Belleville washers, also known as Belleville springs, conical spring washers, coned-disc springs, disc springs, or cupped spring washers, consist of a conical shell that can be loaded along its axis either statically or dynamically. A Belleville washer is simply a type of spring shaped like a washer. Belleville washer works great in applications where metals are expanding and contracting due to thermal expansion. This is because they maintain constant torque as the fasteners elongate and contract.
A Belleville washer consists of a convex disc supported at the outer edge by one force and an opposing force on the center of the disc. Belleville washers can be used singly, or in stacks, to achieve a desired load & travel. The advantage of a Belleville washer is that it generates a high force in a very short spring length and with minimal movement when compressed.
- These cupped spring washers flatten out as pressure is applied to them.
- They are commonly used to produce exceptionally high loads in small areas.
- Coned disk washers can absorb and dampen shocks and vibration as well, making them useful in many industries and applications.
Different terms for Belleville Washers
- Belleville
- Coned – Disc
- Conical
- Cupped Spring
- Spring
- Lock Spring
- Conical Spring
- Disc Spring
- Belleville Spring
How do Belleville Washers work?
The conical spring washer has a cone shape that presses against the underside of the bolt head and into the installation material.
This increased tension has several benefits including:
- Vibration Control (Lock Washer)
- Pre-Load
- Increased Load
- Increased Deflection
- Spacing
- Dampen/Absorb Shocks
Due to their resistance to vibrations, conical washers are also considered to be lock washers as they perform a similar function. These disc spring washers are not only useful on their own but can be stacked in several different structures for increased resistance/absorption as well.
Belleville Spring Washer Stacks
Spring washers can be stacked in several structures to increase certain characteristics they produce for optimal performance.
Series Stack
A series stack involves placing the washers, top to bottom so that they create a gap in the middle. This can greatly increase the deflection of the stack by adding a spring-like effect to the washers. *Note: This stack does not increase the load capacity of the fastener assembly.
Parallel Stack
A parallel stack involves placing all of the washers in the same direction. Each added washer increases the load capacity of the stack. *Note: The deflection does not increase based on this stack.
Series/Parallel Stack
The mixed parallel/series stack involves performing both types of stacks in a single fastener assembly. This increases both the load and deflection and can be arranged to suit almost any situation as needed to comply with the project needs
Please note that while Belleville spring lock washers are exceptionally versatile and can be stacked in multiple configurations, the washer that rests against the installation material must always have the widest portion against the material.
Uses of Belleville Washers.
The Belleville washer has been widely known because of its properties that make it stand out among others. These include the following:
- The characteristic curve of a Belleville washer makes it possible to be used in various combinations with the necessary support that an application needs.
- Other washers have limitations when carrying a load, unlike the Belleville washers that can support large loads even with small insulation space.
- Because of its annular shape, it can force transmission in the center thus being able to equally distribute the load.
Industries That Use Conical Washers
- Energy
- Utility Transmission
- Power Distribution
- Pumps & Valves
- Chemical
- Automotive
- Industrial Automation
Can Belleville Washers Be Reused?
Yes, Belleville conical washers can be reused, repeatedly, as long as they are not damaged. Overloading and over-torquing these washers can wear them out over time. As long as they are used properly and checked before reuse, these fasteners can be used again and again to complete projects.
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