English Views: 69 Author: Site Editor Publish Time: 2025-09-02 Origin: Site
1、 Definition
Disc spring (also known as butterfly washer), briefly called disc spring, is an elastic element with the shape of a bottomless metal disc that can bear axial load. It is usually made by processing metal steel strip, steel plate or forging.
1）The structure is compact in the direction of load bearing, can bear large loads under small deformation conditions, occupies small space in the axial direction, and has high deformation energy.
2）It has the characteristics of variable stiffness. According to different height-thickness ratio (h₀/t), it can show mechanical properties such as approximate straight line, gradual decrease, gradual increase, zero stiffness and even negative stiffness.
3）The combination method is flexible and simple, suitable for standardized production, and convenient in use, maintenance and management.
Ordinary leaf springs can be divided into two types according to the support structure, such as no support surface and with support surface, as shown in Figure 1.
1）In terms of materials, GB/T 1972-2005 standard recommends the use of 60Si2MnA or 50CrVA, and can also choose stainless steel, heat-resistant steel, copper alloy, titanium alloy, nickel base or cobalt based alloy and other materials.
2）Size and form tolerance:
China's standard divides the size and load accuracy of disc springs into grade I and Grade II. The main dimensions include inner diameter, outer diameter, thickness and free height.
3）Form and position tolerances: While China's standards do not specify these parameters, the German DIN 2093 standard requires them. For concentricity tolerance: The value is 2.1×T11 when D ≤ 50, and 2.1×T12 when D> 50. The national standard only specifies surface roughness, with detailed specifications available in GB/T 1972-2005.
4）The regulations clearly specify surface treatment, heat treatment, and high-pressure processing. Surface oxidation or phosphating treatments must eliminate harmful defects such as burrs, cracks, or scratches that could compromise performance. Disc springs requiring quenching and tempering should undergo no more than two quenching cycles, with hardness maintained between 42-52 HRC. For Class I disc springs, the single-sided decarburized layer depth shall not exceed 5% of its total thickness. For Class II and III disc springs, this limit extends to 3% (with a maximum of 0.15 mm).
5）Overpressure treatment is a necessary process, which requires the compression of spring not less than 2F_f (the load corresponding to deformation amount of F_f is 0.75h₀), lasting no less than 12 hours, or short compression no less than 5 times.
6）Special surface anticorrosion, strengthening treatment and fatigue, relaxation, creep and other performance requirements shall be determined by the supply and demand parties through consultation, which are not within the scope of compulsory national standards.
Disc springs are divided into three groups according to thickness:
-Group I: thickness t <1.25 mm
-Group II: thickness 1.25 mm ≤ t ≤ 6 mm
-Group III: thickness t> 6 mm
Production process:
-Group I: blank → heat treatment → strong pressure treatment → surface treatment → final inspection → packaging
-Group II: blank → machining (inner and outer diameter) → heat treatment → forging → surface treatment → final inspection → packaging
-Group III: blank → full processing (outer diameter, inner diameter and plane) → heat treatment → strong pressing → surface treatment → final inspection → packaging
Each process shall be inspected, and the final inspection shall be carried out in accordance with national standards or process documents.
