Production status and technical quality level of spring materials
Spring is an industry that depends on raw materials. At present, the annual demand for spring materials (excluding spring leaf) is about 60000 tons. The reality is that domestic spring steel and spring steel wire occupy the low-end market. For high-demand springs, such as suspension spring and valve spring materials for cars, a large part of them need to be imported from abroad, and special-shaped cross-section materials can not even be found in China manufacturer. Japan and South Korea are the countries that export most spring steel wire to China. Sweden, Germany, Belgium, Australia and Taiwan of China also import some materials to China. In recent years, the development of automobile industry has also promoted the production of spring materials. Since the 1990s, nearly ten spring steel wire production lines and five or six special steel plants for spring steel production have been set up in China.
There are countless small wire drawing plants producing various spring steel wires. Although the quality of domestic steel wire is not as good as that of imported products, but its price is low, so it is also used to manufacture mini car, van suspension spring, motorcycle shock absorber spring, low and medium stress door spring, general spring and special-shaped spring. Most of the spring round steel used for hot coil spring is made of domestic materials, and a small amount of it is imported. Compared with the imported round steel, the price advantage of domestic spring steel is not large, and there is a gap in quality specification and variety.
The biggest gap of spring materials in China is the development of new products. In order to comply with the development of automobile to light weight, Japan iron and steel company and spring enterprises have jointly developed a batch of new materials which can be used for the stress of 1200Mpa or even 1300mpa. The intellectual property rights belong to the joint ownership of steel mills and spring enterprises. The technical confidentiality is implemented for other parties and the market is blocked. In this regard, China’s spring enterprises are in the position of Disadvantages.
The development of new materials involves a series of problems such as basic research, steel plant facilities transformation and capital investment. However, the output of spring steel accounts for only a small part of the total steel output, which is difficult to arouse the interest of iron and steel enterprises in R & D, and the gap with foreign countries will be maintained.