Over the years, the domestic automobile industry has not paid enough attention to the coating of truck leaf springs. They even think that leaf springs are medium-thick plate parts. Corrosion is only a bad appearance and will not cause structural damage. In fact, this point of view is wrong. Experiments have proved that if the early rust of the leaf spring is caused by coating process defects and poor corrosion resistance of the coating, the rust spots will become a new source of fatigue for the leaf spring and affect the fatigue life of the leaf spring. , It also reduces the safety of driving and the life of the whole vehicle.
We have checked the relevant information to show that:
1. For domestic vehicles, the fatigue life is about 100,000 times. After driving or rusting for 10,000 to 20,000 kilometers, after the road test, the spring is severely corroded, and the leaf spring breaks first along the rusted part.
2. For European and American imported cars, the fatigue life is about 800,000 times, and the driving or corrosion is 30,000 kilometers. After the road test, the spring is basically free of rust, and the life span is only reduced by about 15%.
In order to improve the service life of domestic leaf springs, the relevant units have analyzed the coating of imported leaf springs. Through external observation, stone impact test and salt spray test, the results are obtained after comparing with the coating quality of domestic leaf springs:
The leaf springs used in foreign medium and heavy vehicles mostly use variable cross-section and less leaf springs, and the coating quality is obviously better than that of domestic springs. Domestic medium and heavy-duty vehicle leaf springs are basically multi-leaf springs, and insufficient attention has been paid to the coating process in product design and actual production. The coating process of foreign medium and heavy-duty vehicle leaf springs is more particular. After single-sided stress shot peening, there is no residual scale on the other side. Oxygen rich zinc coating. Single-piece spraying and assembly touch-up paint ensure good adhesion and corrosion resistance of the coating, ensure the integrity of the overall coating, greatly improve corrosion resistance, and avoid yellow rust.
Rust spots are the fatigue source of leaf spring fracture. In order to improve the service life of the spring, it is necessary to improve the coating quality standard and reach the corresponding salt spray test standard to make the leaf spring more fatigue-resistant.
In the production process of Changda Xingshun leaf spring, single-piece spraying and electrophoresis guarantee 500H salt spray, and the corresponding test standard can only be qualified. The produced leaf spring is more wear-resistant and corrosion-resistant.
