What Are Spring Washers and Their Subtypes?
Washers are a common component found in various assemblies, and they regularly come in the form of a thin, disk-shaped plate with a hole cut out of their center. While the Primary Use of washer is to distribute the load of a fastener, such components may also act as a spacer, spring, wear pad, locking element, vibration reducer, and more. Washers come in many forms, plain, spring, and locking washers being the most common variations. Spring washers in particular are quite beneficial for applications in which vibration is a concern, featuring axial flexibility and fastener security. In this blog, we will discuss the spring washer and common subtypes, allowing you to better understand their role in part assembly.
Unlike a plain, flat washer, spring washers feature an irregular profile that prevents the component from sitting flat on a surface. Instead, the irregularities of the washer are compressed when a load is subjected to the assembly, causing a proportional force to be applied as resistance. With this compression and resistance, the spring washer is able to maintain the tension of the assembly while accommodating for any potential expansion or contraction of materials under pressure. Additionally, the compression and resistance of the washer also mitigates the effects of shock loads as their force is absorbed by the mechanical element.
During such processes, the spring washer may be understood to be similar to a compression spring where the deflection rate of the component is tied to its specific materials and dimensions. The higher the load, the thicker and taller the spring washer should be to ensure proper operations. Curved spring washers are either placed under static or dynamic loads, the former being when the washer is placed in an assembly to retain load. Under a dynamic load, meanwhile, the washer will need to act as a flexing spring, and it is crucial that the yield limit is not exceeded for the integrity of the washer itself.
While washers are designed to return to their resting state and shape after loads are removed, they can eventually face permanent deformation. Generally, the lifespan and rate of fatigue for a particular washer will vary based on its construction materials, many being made from metals such as stainless steel, silicon bronze, and brass. Once plastic deformation begins and some deflection becomes irreversible, the washer has begun facing fatigue.
Depending on one’s particular needs, there are five main classes of spring washers that one may take advantage of. Belleville spring washers, also known as conical spring washers, are components with convex, cone-shaped designs that allow them to take on high loads with little deflection. With their capabilities, Belleville washers may serve applications in which thermal expansion and contraction is a concern. For smaller loads, the crescent or curved spring washer is an optimal choice. With a more uniform spring rate and deflection capacity, crescent spring washers are used for flexible, nonflexible, and load-cycling applications.
Dome spring washers are another form of spring washer that can support high application loads, and their deflection range is known for being small. For concerns with noise, vibration, and general wear and tear, finger spring washers are an optimal choice. With their smooth operations, dome finger spring washers are beneficial as the amount of wear and tear that they face is often lower as compared to some alternatives. The final major type of spring washer is the wave spring washer, and they can act as a cushion spring or spacer for a shaft. With medium load-bearing capabilities and deflection, wave spring washers are most often used for the prevention of fastener loosening when noise and vibration is present in an assembly.
When purchasing spring washers and other hardware components for your operations, it is important that you use the most reliable sources for procurement. NSN Parts Hub is a leading supplier of spring washers and their various part types, offering access to an expansive inventory of parts with competitive pricing and rapid lead-times. Explore our extensive offerings as you see fit, and our industry experts are always ready to assist you through the purchasing process with personalized quotes for your comparisons. Get in touch with one of our team members at your convenience and see how we can serve as your strategic sourcing partner for all your operational needs.