What Are Compression Springs?

Compression springs have the ability to store mechanical energy when they are compressed. Generally, a compression spring consists of an open-coiled, helical spring that provides resistance to compressive loading. As such, when it is subjected to a compression load, it becomes shorter and absorbs a large amount of potential force.  

Once the load is reduced or eliminated on a compression spring, the spring returns back to its original length and form. When weighted, compression springs are more compact. Unlike extension springs, the compression springs’ spiral wire does not touch in each turn when it is relaxed. Instead, it is tightly compressed when stressed.

When selecting a compression spring for your applications, there are various considerations to keep in mind. For example, compression spring end types can be traditional or customized. Standard ends are usually open or closed, or they can be ground or not. Depending on the number of coils, wire size, and outside diameter (OD), open or closed ends will alter the spring rate.

However, if a compression spring is combined with closed ends, the squareness of the loading force is enhanced and the spring buckling tendencies are reduced. Meanwhile, ground ends necessitate additional manufacturing work. Some manufacturers will offer closed and ground ends in their general catalog stock designs. An example of a special end includes expanded coils that snap into ring grooves.

Material Considerations of Compression Springs

There are also a number of material considerations to factor in when choosing a compression spring. For instance, carbon steel and exotic alloys make up some of the few possible spring materials. The most popular material is typically music wire composed of a high carbon spring steel.

Stainless steel 302, in particular, improves overall corrosion resistance, but is not as strong as music wire. Nickel alloys are often go-to choices for their extreme high or low operating temperatures, specialized corrosive conditions, and non-magnetic properties. Additionally, copper alloys may also be used as a result of their superior electrical conductivity and corrosion resistance.

Physical Considerations of Compression Springs

If the compression spring is going to be placed into a hole, the outside diameter must be taken into consideration. In addition, if the internal components of the device surround the spring, they must be measured with precision. If the spring is going to be used in a tube or a bore, you must remember that the spring’s outer diameter (OD) becomes larger when it is compressed. If the compression spring passes over a shaft or mandrel, you must take note of the spring’s inner diameter. To prevent friction, there must be a ten-thousandth of an inch of clearance between the shaft and the spring. Lastly, the wire diameter and the total number of coils has a major impact on the solid height of the spring; thus, you must make sure that the loaded height is not shorter or taller than the solid height. 

Manufacturing Processes and Materials Used to Make Compression Springs

There are three key parts to the manufacturing process required to make a compression spring. The first step consists of coiling, where the wire is straightened out before entering a coiler. Typically, the coiler imposes stress on the wire, oftentimes making it brittle. To remedy this, the second step consists of heating the spring in an oven, allowing it to solidify in its new shape and generate metallic links. Based on the application at hand, the third step varies. The wire can be placed through numerous finishing processes. For example, they can be grinded, set, coated, packaged, or subjected to strength peening.

Applications and Advantages of Compression Springs

Compression springs offer a wide range of advantages that make them ideal for a myriad of applications. That being said, they find use in automobiles, door locks, pens, aeronautics, firearms, and medical devices. Some of the few benefits they provide include the prevention of another component’s movement, the alignment of components, and the application of continuous pressure. More than that, they are lightweight, affordable, and require little maintenance. In terms of disadvantages, compression springs lose stability and shape over time, may buckle if axial loads increase, and get weaker if compressed for extended periods of time.

Types of Compression Springs

1. Convex Compression Springs
2. Conical Compression Springs
3. Disc Springs or Belleville Springs
4. Concave Springs
5. Straight Coil Springs
6. Volute Springs
7. Variable Pitch Springs
8. Magazine Springs
9. Torsional Springs

Conclusion

Industrials 3Sixty is a leading supplier of compression springs, as well as countless other top-quality components found in many industrial sectors. With over 2 billion new, used, obsolete, and hard-to-find items on our database, customers can easily meet rigid time constraints and strict budget parameters. Get started with a competitive quote on any featured parts and see how Industrials 3Sixty can serve as your strategic sourcing partner!