Based on the nature of the force, the manufacturer divided springs into different categories—tension, compression, torsion, and bending springs.
Extension springs are helical springs that bear axial tension, and supplier manufacture extension springs using circular cross-section materials. When not under load, the tension spring coils are usually tight, and there is no gap between the coils.
The compression spring is a helical spring that bears the pressure. The cross-section of the material it uses is primarily circular and made of rectangular and multi-strand steel coils. The spring is generally of equal pitch. When receiving an external load, the spring shrinks and deforms to store deformation energy.
Torsion springs are coil springs. Torsion springs can store and release angular energy, in addition to statically fixing a device by rotating a moment arm about the central axis of the spring body—the ends of a torsion spring secure other components. As the different parts rotate about the center of the spring, the spring pulls them back to their original position, creating a torque or rotational force.
Manufacturing of springs
The manufacturing process of the coil spring includes: rolling, hook making or finishing of the end ring, heat treatment, and process performance test.
In mass production, the manufacturer coils spring steel on a universal automatic spring coiling machine. It is made on an ordinary lathe or by hand in single-piece and small-batch production. When the diameter of the spring wire is less than or equal to 8mm, the manufacturer commonly uses the cold rolling method. Cold rolling requires heat treatment before rolling and low-temperature tempering after moving. When the diameter exceeds 8mm after heating, use the hot rolling form (hot rolling temperature 800 ° C ~ 1000 ° C). The manufacturer will then quench, and temper the spring steel at medium temperature shortly after hot rolling. Afterward, an inspector will conduct a surface quality inspection after the spring formation. And other defects, springs subject to variable loads must also undergo surface treatment, such as shot peening, to improve the fatigue life of the spring.
spring end structure
In addition to the number of good turns n that participate in the deformation of the compression spring, to make the compression spring work evenly and ensure that the center line of the spring is perpendicular to the end face, the two ends of the spring each have 3/4 to 7/4 turns and act as support tightly, called a supporting turn when it does not participate in deformation.
Tension springs have hooks at the ends for easy installation and loading. There are four types of commonly used end structures, such as semi-circular and round shackles. Due to the ease of manufacturing, manufacturers widely use these shackles. But because of the immense bending stress at the transition of the hook, they are only suitable for springs with a diameter of spring wire d≤10mm. Adjustable and swivel hooks hold up well and allow turning to any position for easy installation.
