1. Springs without support rings and springs with too thin steel wire diameters should not be welded to the spring head, but the end cable should not be significantly loose, and should be deburred. For multi-strand springs that need to be welded to the head, the length of the welded part should be less than 3 times the cable diameter (the longest is no more than 10 mm). The heating length should be less than one circle, and it should be polished smoothly after welding, and the welding part should be locally annealed at low temperature during gas welding.
2. The support ring can choose two methods: cold and hot, according to product requirements. It is not allowed to heat the spring to sparking or whitening by using heat and the method of heating, and the temperature of silico-manganese steel shall not be higher than 850°C. The support ring and the effective ring should be in effective contact, and the gap should not exceed 10% of the nominal gap between the rings.
3. The characteristics of the multi-strand spring can be determined by the adjustment lead, and the cable distance can be adjusted as necessary during winding. The twisting distance can be 3~14 times the steel wire diameter, but generally 8~13 times is better. The spring force is also closely related to the free height, the end ring, the outer diameter and the performance of the steel wire. It can be changed by adjusting one or several of them.