Spring strengthening process

Spring strengthening process
Suspension spring strengthening

Thanks to the high-stress and lightweight design, the weight of suspension springs has been greatly reduced in recent years, and it is very common that the stress of the suspension springs of new models>1000Mpa. bomb

The spring service under such high stress has exceeded the limit that the material can withstand, so it must be supplemented by other strengthening methods (such as shot/shot peening)


The main engine manufacturer adopts very strict test standards for automobile suspension springs. The longest test period is as long as 70 days (10 weeks).

Suspension springs working under high stress conditions will cause corrosion fatigue failure once the surface is subjected to stress corrosion.

A broken tire may cause major safety and personal accidents.

Shot/shot peening is the most effective strengthening method for suspension springs. After proper shot peening, the fatigue life of high-stress springs can be increased by more than 5 times.

At present, most of the spring blasting/shot peening uses steel wire cut shots, and multiple shot blasting (different shot diameters) are commonly used in the process. Strong spring surface pressure

Degree and depth are important indicators to measure the effect of shot peening. The surface stress of good shot peening is at least above -600Mpa, and it can reach at a distance of 50um from the surface-

800Mpa, the surface pressure of the stress shot peening spring can reach -800Mpa or more, and it can reach -1200Mpa at a distance of 50um from the surface

At present, well-known suspension spring manufacturers at home and abroad, such as Liaoyang Kesuo, etc., generally use a continuous pass-through type roll cage strengthening equipment, and the workpiece

Convey via a suspended conveyor chain. Each part must be in three shot blasting positions, according to the set time for three shot blasting strengthening treatment

cycle. After the strengthening is completed, the throwing head stops, the discharge door is opened, the strengthened workpiece is automatically lifted out, the new workpiece enters, and the new cycle starts. The device

The production capacity can reach 500 pieces/hour.

Leaf spring strengthening

A continuous-through shot blasting equipment can be used to strengthen the leaf springs one by one individually, exposing the geometric concave surface of the leaf spring to high speed

The pill shed. A typical model includes a throwing head for projecting the top of the leaf spring, and a throwing head is installed on the side to spray the left and right sides of the leaf spring at the same time.

The passing speed of this standard leaf spring strengthening equipment is 10 feet per minute. If a higher production speed is required, the number of polishing heads can be increased and the motor can be adjusted.

frequency. Under working conditions, leaf springs are repeatedly affected by unidirectional bending stress, so they are sometimes stressed by stress. During the strengthening process,

The simulated leaf spring will be subjected to “stress strengthening” in the future use process, so that it will be subjected to the same “static stress” in the direction of bearing the load.

When, it is shot peened. After strengthening, release the applied static stress. Experiments have proved that stress strengthening is more advanced than conventional strengthening

Step to extend the service life of the leaf spring.

Round spring reinforcement

Round springs, due to their spiral geometry, are harder to strengthen than flat surface leaf springs. In addition, it must be strictly evaluated

The strengthening effect of the cross section of the round spring, so as to fully understand the resistance of the round spring against fatigue fracture.

The round springs are individually sent to the shot blasting chamber via a continuous conveyor chain system. A set of parallel rollers are installed in the shot blasting chamber. While strengthening, the rollers are not

Stop rolling and drive the circular spring to move forward while rotating. This way of rotation allows the high-speed pill flow to pass between the rings of the circular spring and hit the inner ring of gold.

On the surface, there is exactly the place where the stress of the circular spring is most concentrated.

For applications with high productivity requirements, an enhanced device that can spray two round springs at the same time can be selected. The latest research and development result is based on the original shot blasting

Based on the equipment, combined with multiple nozzles, used for more targeted and concentrated shot peening of the specific area of ​​the round spring (stress concentration to please).