Matters needing attention in spring shot peening operation

Spring is one of the earliest parts of shot peening used in production, especially those various compression coil springs, leaf springs and torsion bar springs that are subject to cyclic load and are prone to fatigue damage.

Shot peening is arranged after the spring is formed and heat treated. Small metal balls or metal particles are used to spray on the surface of the spring countless times at a speed of tens of meters per second to produce many small pressure pits, which are uniform and thin. It covers the surface layer of the spring and produces work hardening on the surface. At the same time, it can also reduce or eliminate the harmful effects of spring surface defects (such as small cracks, bumps, gaps, and decarburized layers), thereby effectively improving the fatigue life of the spring .

Attention should be paid during shot peening:

①Choose the type and specifications of the projectile correctly to avoid using sharp-edged projectiles to damage the spring surface;

② Choose a shot blasting machine reasonably, requiring high injection speed;

③The shot peening time should be appropriately longer when the conditions are possible, so that although the strength of the spring cannot be increased, it can increase the coverage of shot peening and also increase the fatigue life.