Issues to be noted in spring processing

Due to product structure limitations, multi stranded springs generally have the characteristics of high strength and good performance. Require the material to ensure the final performance in terms of spring strength and toughness. During the processing of multi strand springs, it should be noted that: 1. The support ring can be used in two methods: cold and hot according to product requirements. It is not allowed to heat the spring to spark or whiten using hot mixing methods, and the temperature of silicon manganese steel should not exceed 850 ℃. The support ring and the effective ring should have effective contact, and the gap should not exceed 10% of the nominal gap between the rings. 2. The characteristics of multi strand springs can be determined by adjusting the lead, and the cable distance can be adjusted as necessary during winding. The twist distance can be 3-14 times the diameter of the steel wire, but generally 8-13 times is preferred. The spring force is closely related to the free height, parallel end coil, outer diameter, and steel wire performance, and can be changed by adjusting one or several of them. 3. Springs without supporting rings and springs with wire diameters that are too thin should not have spring heads welded, but the end steel cables should not have obvious looseness and should be deburred. For multi stranded springs that require welding of the head, the length of the welding area should be less than 3 times the cable diameter (the longest should not exceed 10 millimeters). The heating length should be less than one circle, and it should be polished smooth after welding. During gas welding, the welding area should undergo local low-temperature annealing. 4. The surface treatment of springs generally requires phosphating treatment, and other treatments can also be carried out. When zinc and cadmium are to be coated, dehydrogenation treatment should be carried out after electroplating. After dehydrogenation, 3% (not less than 3 pieces) of samples should be taken for retesting, and there should be no fractures during the retesting. Springs should be cleaned of surface dirt, salt marks, and oxide skin. The method can be sand blowing or gasoline cleaning, but acid washing cannot be used. 5. The compression time for important springs is 24 hours, while for ordinary springs it is 6 hours or 3-5 consecutive compressions, each lasting 3-5 seconds. When tightening, the gap between the spring and the core shaft should be 10% of the core shaft diameter. If the gap is too small, it is difficult to operate, and if the gap is too large, it is easy for the spring to bend and deform. If one of the springs is broken during compression, the rest should be reprocessed.