1. Spring setting treatment, Setting spring "stands treatment", compresses the heat-treated compression spring to the height of the working limit load or high pressure and height (the length of the tension spring stretched to the working limit load, and the torsion spring is twisted to the working limit Niu corner), one or more short-term compression (tension, torsion) in order to achieve the main purpose of stabilizing the spring assembly size is a process method.

2. Heating and setting treatment Hot-setting is also called "heating and setting treatment". Standing treatment under conditions higher than the stable working conditions of the spring.

3. Strong pressure treatment, a process method to compress the compression spring to the surface of the spring material to generate beneficial residual stress opposite to the working stress, so as to improve the spring's bearing capacity and stabilize its geometric size.

4. Heating and pressure treatment, high pressure treatment under higher than spring working conditions.

5. Forced tension treatment, a process method to stretch the tension spring to the surface of the spring material to generate beneficial working stress reverse residual stress, with high spring bearing capacity and stabilization of its geometric dimensions.

6. Heating and strong tension processing, strong tension processing under the condition of higher than the spring working stability.

7. Strong torsion treatment, to twist the torsion spring to the surface of the spring material to produce beneficial residual stress that is opposite to the working stress, which is a process method for high spring load-bearing capacity and stabilization of its geometric dimensions.

8. Heating and strong torsion treatment, which is higher than the spring's working temperature.

Analysis of the reason for the abnormal hardness of the spring steel reeds of Dongguan Hardware and its solutions.

Heat treatment is generally less likely to cause crack defects in the reed. The reasons are: improper heat treatment process, improper adjustment of tooling, and operator error. Improper heat treatment process means that the heating temperature of the reed is too high and the holding time is too long, which causes the austenite grains in the reed structure to be coarse. Form heat treatment cracks.

Solution: Use a mesh belt furnace to process the reeds, control the heating temperature of 790 degrees, control the holding time, direct oil quenching, and temper in time after cleaning, which can effectively solve the heat treatment crack defects caused by Dongguan hardware springs.