Compression springs-six major manufacturing steps

Compression springs, one of the most common types of springs, are basic mechanical components in industrial equipment, construction, and daily life. They store and release energy and play a role in buffering and elastic support.

The manufacturing process of compression springs requires a combination of multiple processing steps. Ensuring precise processing technology and strict quality control at each step is the key to ensuring the spring’s performance and meeting industrial needs. In this article, we will introduce the manufacturing process of compression springs, from material selection to performance testing.

1. Selecting the right material

Choose the right material according to the compression spring's purpose to ensure its performance and service life. Common materials include carbon steel (such as 65Mn, 70# steel), suitable for general use; alloy steel (such as 50CrVA, 55CrSi), used for high strength and fatigue resistance requirements; and stainless steel (such as SUS304, SUS316), suitable for corrosion resistance or high-temperature environments.

2. Rolling of compression springs into shapes

This is a critical step in the manufacture of compression springs. It involves using a CNC spring machine and forming dies to coil the material into the compression springs' initial form.

There are 2 methods of spring coiling:  cold coiling and hot coiling. Cold coiling is to coil the spring wire at room temperature, suitable for compression springs with smaller diameters (d≤8mm). Hot coiling is ideal for compression springs with larger diameters and heavy loads (d>8mm), which requires heating the material to a specific temperature before coiling.

3. Heat treatment process

After the compression spring is rolled, it needs to be heat-treated. This step is to improve the strength, toughness, and fatigue resistance of the material while eliminating the internal stress generated during processing to ensure the long-term stability and service life of the compression spring.

There are usually two steps of heat treatment: quenching and tempering.

Quenching involves heating the spring to 850℃～950℃ (depending on the material), keeping it for a certain period, and then cooling it quickly. This step can improve the spring's hardness and strength.

Tempering: Heat the quenched spring to 300℃～500℃, keep it at this temperature for a period, and cool it (air cooling). This can eliminate the spring's brittleness after quenching, restore toughness, and stabilize the material's structure.

4. Surface treatment of compression springs

Compression spring surface treatments can increase their durability. Zinc/nickel plating improves the corrosion resistance of compression springs by forming a protective film on the spring surface. Oxidized: An oxidized film can be formed on the surface of compression springs to provide a protective coating that enhances serviceability and durability.

5. Finishing of compression springs

Spring end processing: The end faces of compression springs are generally ground to ensure their perpendicularity, maintain contact between the two support coils and other components, and reduce deflection.

Grinding and polishing: This step improves the compression spring's surface quality and dimensional accuracy, reduces stress concentration, and increases fatigue life. The spring surface is polished to reduce friction loss.

6. Performance Testing

Compression springs need to be tested for performance before being put into use to ensure that they are reliable and durable and meet the operational needs of the equipment. Comprehensive evaluation from spring stiffness, load carrying capacity to fatigue life, etc., can be timely detection of potential problems with the spring, and take appropriate measures to improve.

Spring stiffness: Place the compression spring on the pressure tester and measure its displacement change by applying different compression loads.

Load capacity test: Apply pressure at a specified compression amount (usually the working height) to measure the maximum load that the compression spring can withstand.

Fatigue life test: Use a fatigue tester to simulate working conditions, perform fatigue tests on the compression spring during the loading and unloading cycle, and measure the springs' durability by observing the number of cycles of fracture or failure.

Dynamic performance test: Test its dynamic performance, such as response speed and deformation recovery ability, through dynamic loading and unloading. Test whether the dynamic working performance of the compression spring meets the equipment operation requirements.

Conclusion

The processing of compression springs is a complex process involving multiple steps, including material selection, spring rolling, surface treatment, and performance testing. Each step will affect the quality, performance, and spring service life. Precise machining and stringent quality control are the keys to ensuring that springs perform consistently and meet industrial demands.

The manufacturing process of springs is the basis for their application performance. Choosing JLCMC as a supplier of customized springs, we provide industrial standard products to ensure that each production step of the springs has undergone strict quality control to ensure the best performance and service life.  Click the image below to learn more about JLCMC, and register to enjoy $19 coupons!