To a large extent, disc springs are replacing cylindrical coil springs. It is often used in buffer and vibration damping springs for heavy equipment such as presses, compression springs for clutches and safety valves in automobiles and tractors, and energy storage devices for motorized equipment.
Disadvantage: Load deviation is difficult to guarantee.
According to the cross-sectional shape, disc springs can be divided into three categories: ordinary disc springs with a rectangular cross-sectional shape, disc springs with radial grooves, and trapezoidal cross-section disc springs. Ordinary disc springs are divided into two categories: no bearing surface and bearing surface. The disc spring with radial grooves can open a plurality of evenly distributed grooves in the radial direction relative to ordinary disc springs, from the inner hole to the outer circle direction, or to the inner hole direction of the outer circle. Trapezoidal section disc springs can be divided into two categories: the thickness of the inner side is greater than the thickness of the outer circle, and the thickness of the inner side is smaller than the thickness of the outer circle.
Since the deformation and load values of the single-leaf spring usually do not meet the requirements of use, it can be used as a group that constitutes a disc spring component (column). Typical combination methods are: overlapping combination disc springs, composite combination disc springs and other combination disc springs.
Compared with cylindrical coil springs, disc springs have the following characteristics
First, the load-deformation characteristic curve is nonlinear.
Second, the disc spring is thin, easy to form assembly parts, can implement block assembly and replacement, and is convenient for maintenance.
Third, disc springs with radial grooves have zero stiffness characteristics. This feature can be used when the spring force needs to remain substantially stable within a certain deformation range.
Fourth, the dust-absorbing performance of the disc spring is not lower than that of the cylindrical coil spring. When the overlapping combination is used, due to the friction between the disc springs, there is a great damping and the impact energy is released.
Scope of application and material selection of disc springs
Flange pre-fixed disc springs are suitable for safety accidents caused by flange failures. Warm clothes have big swings. Flanges with a bolt length-to-width ratio less than 3; situations with vibration or alternating forces; situations with large pressure fluctuations; elsewhere with leakage problems.
Generally, installing disc springs on both sides or sides of each bolt can meet the deformation compensation needs in most cases, and in special cases, various combinations of disc springs can be used for compensation.
The choice of disc spring material usually depends on the bolt material and restoring force requirements. The materials commonly used in petrochemical plants are 693F and 20813. In special cases, different alloy disc springs can be used.
Proper selection of pre-retained disc springs is critical to controlling leakage. Only when the disc spring works in the constant load area (ie, the effective compensation area), the disc spring can really play a compensating role. If the preloading disc spring with too small pressure is wrongly selected, the small preloading force required for sealing cannot be provided after the bolt preloading force is relaxed by 30%. The effect is like not using a disc spring. The wrong choice of a pre-fixed disc spring with excessive pressure will result in permanent deformation beyond the elastic limit of the gasket material, which is less effective than not using a disc spring.