Common problems of mold spring

A. Why does the spring break during use?
a. The mandrel is too small or the spring is used horizontally, the spring and the mandrel are worn and broken;

b. When the mandrel is too small / the assembly surface is not flat / the parallelism of the positioning surfaces at both ends is not good, it will cause the spring to be compressed and twisted, causing high pressure locally and breaking;

c. The mandrel is too short and the end is not chamfered, which will cause friction and wear between the spring and the mandrel and break;

d. The use of foreign matter between the spring coil and the coil reduces the actual effective number of coils, resulting in high stress and breaking;

e. The spring is used in series to make it bend and exceed the length of the mandrel or counterbore, or the weaker load will break due to the small difference in the spring itself;

f. Use exceeding the maximum compression amount to generate high-efficiency stress to break the spring;

g. The spring material is uneven, or the impurity content exceeds the standard, resulting in stress concentration fracture;

h. Overburning, rusting, high hardness, and excessive rolling of the spring will reduce its tensile and compressive strength and cause fracture.

B. Why does the spring show “insufficient elasticity” during use?

a. Unreasonable design and production parameters of non-standard springs: only pay attention to parameters such as outer diameter, inner diameter, and length, and often ignore the cross-sectional area and pitch of the wire, which leads to insufficient elasticity;

b. The standard spring selection is unreasonable: due to the low price of the picture, the lighter load type is selected and cannot bear the heavier load, resulting in insufficient elasticity;

c. The spring quality grade is wrong: accidentally or deliberately use ordinary springs as high-quality springs or imported springs, which leads to the feeling that the elasticity is not enough;

d. The use of exceeding the specified temperature leads to reduced elasticity or even loss of elasticity;

e. The spring wire itself is too soft, or the spring quenching temperature is too low or the holding time is not long enough, or the tempering temperature after the spring is formed is too high and the time is too long, resulting in the tensile and compressive strength being low but the elasticity is not enough-this is the real meaning The elasticity is not enough.