Vacuum Heat Treatment of Wave Springs

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SIMUWU aims to produce high-efficiency heat treatment equipment to help heat treatment enterprises in production. The following is the process flow of the 60Si2MnA wave spring treated in the VOGQ vacuum oil quenching furnace.

The wave spring is an important part installed on the high-pressure plunger spindle. It is connected to the end face seal structure of the spindle. The upper end is a V-shaped sealing ring and a V-shaped sealing ring, and the lower end is a graphite ring and a steel sleeve, under pressure when the spindle is running

60Si2MnA steel is a kind of high-quality spring steel with a wide range of uses. It has good hardenability, high strength and elastic limit after quenching and tempering, and also has high yield ratio, anti-relaxation ability and anti-tempering stability. The disadvantage is that this kind of steel has a large tendency to decarburize, which has a direct impact on the strength and fatigue life of the parts. In addition, because the thickness of the spring sheet is very thin, only 0.4mm and the waveform is complex, it is difficult to meet the design requirements according to the conventional heat treatment specifications, and it is easy to deform.

The biggest advantage of using vacuum heat treatment: small heat treatment deformation; improve the mechanical properties of the workpiece, prolong the service life; save energy; reduce pollution. The vacuum heat treatment of the elastic element can avoid the unfavorable factors affecting the fatigue life of the spring, and the positive effect of vacuum degassing to improve the toughness of the material can improve the fatigue life and reliability of the spring.

Process parameters: In order to prevent decarburization, vacuum annealing, vacuum quenching and vacuum tempering are used from the annealing of raw material steel strips. The specific process of annealing treatment is as follows:

1. Raise the temperature to 750°C at 30°C/min, and evacuate until the degree of vacuum is less than 1.33Pa and continue to heat for 30 minutes.

2. Raise to 850°C at 30°C/min and continue heating for 1.5 hours.

3. Introduce Ar gas, cool to below 250℃, and release.

60Si2MnA spring steel contains Mn element with higher vapor pressure. Therefore, the vacuum degree of Si-Mn-based spring steel is less likely to be too high during quenching and heating.

The vacuum quenching and vacuum tempering process is as follows:

1. Raise the temperature to 550°C at 30°C/min, evacuate until the degree of vacuum is less than 0.67Pa and continue to heat for 30 minutes.

2. Raise to 860°C at 30°C/min and continue heating for 70 minutes.

3. Fill with Ar gas, while the workpiece is immersed in oil and quenched to room temperature.

4. Re-temper and heat to 440℃, the vacuum degree is less than 1.33Pa, heat for 90 to 120 minutes, and then cool.

The test results show that after 600 fatigue tests of the wave spring processed by this method, the technical indicators of the wave spring fully meet the design requirements, and no cracks are found in the magnetic inspection of the specimens and parts after the fatigue test. .

Through the VOGQ series vacuum oil quenching furnace produced by SIMUWU, the above processes can be continuously completed in the same vacuum furnace. SIMUWU is equipped with a mature team of engineers, complete installation and after-sales service, convenient and efficient production, and is a high-quality choice for heat treatment plants.