1. The stress relief annealing of torsion spring manufacturer has a great influence on the initial tension of spring. The initial tension of torsion spring manufacturer should be controlled mainly by the coil spring, and the stress relief annealing temperature only plays an auxiliary role.

2. The spring stress relieving reduces the residual stress, and the material properties also change, so the shape and size of the spring will also change. For example, the outer diameter of spiral spring after stress relieving will change, and the starting change is related to the material and spring size. Therefore, according to the actual situation of size change, the spring should be pre-set after forming.

3. Stress-relieving annealing process after spring shot peening. Shot peening of the processing layer, like the general plastic deformation of the processing of materials, due to the internal strain will cause the elastic limit and other properties. However, shot-peening treatment is the strengthening effect obtained by residual stress. Too high temperature of de-stress annealing will reduce the effective residual stress. Therefore, the de-stress annealing temperature is usually 180~220℃, and the holding time is 20~30 minutes.