Causes of insufficient spring force

1. The design and manufacture parameters of non-standard spring are unreasonable: only pay attention to the outer diameter, inner diameter, length and other parameters, often ignore the size of wire cross-sectional area and pitch, resulting in insufficient elasticity;
2. Unreasonable selection of standard spring: due to the low price of the drawing, the lighter load type is selected, which can not bear the heavy load, resulting in insufficient sensory elasticity;
3. Wrong spring quality grade: unintentionally or intentionally use ordinary spring as high-quality spring or imported spring, resulting in insufficient elasticity;
4. The elasticity is reduced or even lost when it is used beyond the specified temperature;
5. The spring wire itself is soft, or the quenching temperature of the spring is low or the holding time is not long enough, or the tempering temperature is too high and the time is too long after forming the spring, which leads to the tensile compressive strength against the elastic force is not enough.