The permanent deformation of the spring is one of the key reasons for the ineffectiveness of the spring. The permanent deformation of the spring will cause the deformation or load of the spring to exceed the dimensional tolerance range, and endanger the normal operation of all mechanical equipment. Ways to check the permanent deformation of the spring:
1. Quickly resolve the permanent deformation of the spring with high temperature and air-break brake: reduce the spring to a certain height or tightly, then put it in boiling water or incubator for 10 to 60 minutes, then take it out and unload it to check its arbitrary height and Give the working load at the working height.
2. Long-term indoor temperature shut-off brake to solve the permanent deformation of the inspection spring: at the indoor temperature, the spring is reduced or compressed for several days, then unloaded, and the random height is checked and the working load at the given working height is checked.
Spring fracture and influencing factors
The fracture and destruction of the spring is also one of the key invalid ways of the spring
Spring fracture methods can be divided into: fatigue fracture, environmental pollution (alkali brittleness or intergranular corrosion fracture) and load fracture.
The fatigue fracture of the spring:
The fatigue and fracture of the spring are due to factors such as incorrect design, shortcomings of raw materials, unreasonable manufacturing, and hard work environment.
Fatigue cracks usually start in the high ground stress area of the spring, such as the shackle of the tension spring, the inner surface of the reduced spring, and the two sides of the reduced spring (the reduced spring produced and processed on both sides).
The hazard of endurance to fatigue life
(A) A spring that works under a stable load has a much shorter fatigue period than a spring that works under a stable deflection standard.
(B) The fatigue life of springs subjected to unilateral loading appears to be longer than that of springs subjected to double loading.
(C) A spring with a large load amplitude has a much shorter fatigue life than a spring with a smaller load amplitude. Erosion fatigue and friction fatigue Erosion fatigue: Under the erosion standard, the fatigue limit of the spring material is significantly reduced, and the fatigue life of the spring is also greatly shortened.
Friction fatigue: The condition of damage caused by small cracks caused by friction damage is called friction fatigue.
Spring load break
When the additional load of the spring exceeds the ultimate ground stress that the spring risk cross section bears, the spring will break. This type of fracture is called load fracture.
The way the load breaks
(A) Fractures caused by strong cracks and bends;
(B) Fracture caused by impact load;
(C) Fracture caused by axial load.