Precautions during spring processing

The spring processing technology is very complicated and particular. We need to master certain knowledge to produce high-quality springs. Especially, we must be clear about the problems that need attention in the spring processing process, because this has a great impact on subsequent production and product quality. What are the specific precautions in the spring processing? Let's share it with you. Through understanding, you will find more different spring worlds.

1. Spring head shall not be welded when the diameter of spring and spring wire without supporting ring is small, but the end wire rope shall not be loose obviously and shall be deburred. For the multi strand spring with head to be welded, the length of the welding part shall be less than 3 times the cable diameter (the longest shall not be more than 10mm). The heating length shall be less than one circle, and shall be polished smoothly after welding. During gas welding, the welding parts shall be subject to local low temperature annealing.

2. According to the product requirements, the support ring can be cold combined and hot combined. It is not allowed to heat the spring to spark or whiten by hot combination, and the temperature of silicon manganese steel shall not be higher than 850 ℃. The bearing ring and the effective ring shall be in effective contact, and the clearance shall not exceed 10% of the nominal clearance between rings.

3. The characteristics of the multi strand spring can be determined by the adjustment lead, and the cable pitch can be adjusted when winding. The screw pitch can be 3~14 times the wire diameter, but generally 8~13 times is preferred. Its spring force is also closely related to free height, parallel end ring, outer diameter and wire performance, which can be changed by adjusting one or more of them.

4. The compression time of important spring is 24 hours, ordinary Spring It shall be compressed for 6 hours or 3~5 consecutive times, each time for 3~5 seconds. When pressing, the clearance between the spring and the mandrel should be 10% of the mandrel diameter. If the clearance is too small, it is difficult to operate. If the clearance is too large, it is easy to bend the spring. If one of the springs breaks during compression, the rest shall be reprocessed.

5. For the multi strand spring with a large H0/D2 value, attention should be paid to its deformation during heat treatment, and proper heat treatment equipment should be selected considering whether it passes through the mandrel and the placement method. Under the condition of repair, multiple tempering and hot pressing can be carried out to achieve the purpose.

6. The spring surface can be treated by phosphating generally, and other treatments can also be carried out. When zinc and cadmium are to be coated, hydrogen removal treatment shall be carried out after electroplating. After hydrogen removal, 3% (not less than 3 pieces) shall be sampled for retest and standing treatment. No fracture is allowed in the retest. The surface dirt, salt stain and oxide skin of the spring shall be removed by sand blowing or gasoline cleaning, but acid cleaning is not allowed.