Application development trends of the spring industry:
Some experts in the spring industry in China believe that with the development of the main engine, the spring product market in China will also grow simultaneously. It is estimated that by 2010, the sales of the whole industry will exceed 4 billion yuan, and the proportion of the automobile and motorcycle industries in the spring market will be Over 50%. At the same time, in order to adapt to market changes, the spring industry will show new development trends in the next few years:
1. The emergence of new combinations. In the next few years, China’s spring industry will still be dominated by small companies, but some advantageous companies start from the market and business strategies, use the capital, technology and talent advantages in their hands to merge and acquire some companies to obtain The required production factors and market resources, most of the state-owned and collective enterprises in the spring industry will be transformed into joint-stock or private enterprises.
Second, price competition turns to technology and quality competition. With the intensification of market competition, the profit margin of the spring industry has become smaller and smaller. In addition, the main engine manufacturers have higher and higher requirements for the quality of accessories, and companies can no longer rely on simple price reductions to win Market, technology and quality have become the key to competition.
From July 1, 2006, China’s auto parts tariffs will be reduced to 10%, and the final prices of suspension springs, valve springs, stabilizers and other products for the automotive industry will gradually be in line with international prices, and they will be mini vehicles. , The products supporting the van have undergone fierce market competition. The current price has a certain degree of competitiveness compared with the international market, but the quality level cannot compete with similar products. Other products, especially products for motorcycles and some small springs The price is already lower than the international market price, so the price of similar foreign products is not a threat to us, and the competition is mainly manifested in quality.
3. Products are developing towards light weight and high reliability. A rough estimate is that in 2010, the annual demand for suspension springs in China’s automobile industry was about 8 million pieces, and the annual demand for valve springs was about 30 million pieces (excluding motorcycles and diesel engines) The technical development trend of these two springs is generally lightweight (high stress) and high reliability. For the currently emerging suspension springs and valve springs with special-shaped cross-sections, due to the high material prices and complex manufacturing processes, the production costs are high Because of the circular section spring, there is no sign that the special-shaped section spring will completely replace the round section spring.
The correct use of spring:
Please avoid the following improper use
1. The use exceeding the maximum compression (300,000 times condition, the use of the connecting piece is close and long)
The pressure is generated and then breaks, and the use close to the close length will make the spring wire gradually close like this.Because the spring fixed number becomes higher, the load curve will increase accordingly, and the high stress will cause the spring to break when it is close. Please do not use more than 300,000 Back.
2. Use of spring series
When used in series, the spring will bend and exceed the length of the guide pin or counterbore, which will cause a fracture of the same reason, and the weaker load will suffer a greater compression surface fracture due to the slight difference in the load of the spring itself.
3. Use without preload
The spring is twisted due to the up and down vibration of the spring due to the gap.If there is preload, the spring is relatively stable.
4. The use of no spring guide
If it is used under dance spring guidance, it is easy to cause the bottom of the spring and the body to twist. The local high pressure of the twisted part is the main cause of the spring fracture. Please be sure to use an inner diameter guide pin or an outer diameter guide device. .
5. Spring outer diameter and counterbore
If the countersunk hole and the spring gap head are too small, the outer side will expand due to the spring compression and the countersunk hole friction will cause a concentrated break. The better countersunk hole diameter is the spring outer diameter + 1.5mm. Please use the spring with a longer free length Counterbore shape.
6. Use the spring horizontally
When the spring is used horizontally, the guide pin and spring will wear and break.
7. When the length of the guide pin and the depth of the counterbore are short
The guide pin is too short, it will cause the guide pin head and the spring to wear and break. The ideal length of the guide pin is set to more than 1/2 of the spring length, and please reverse the C3 chamfer.
8. When the flatness of the assembly surface is poor
Poor parallelism of the assembly surface will cause the spring to twist, local high-pressure fractures, and in the case of poor parallelism, the spring will be twisted and more than 300,000 times of use will cause the spring to break. Please improve the assembly surface under the conditions of no more than 300,000 times of use Parallelism.
9. About spring inner diameter and guide pin
If the gap between the guide pin and the guide pin is too small, it will cause the collision and wear of the inner diameter. The abrasion part is the main cause of the spring fracture. On the contrary, if the interval is too large, the spring will twist and break. The best is the inner diameter of the spring -1.0mm or so. For longer springs (free length/outer diameter greater than 4), please use a step or guide pin to avoid collision with the guide pin when the spring body is twisted.
10. Change or use
When using a spring, the spring is twisted and the inner ring spring is inserted into the outer ring (or the outer ring is inserted into the inner ring), causing a break.
11. Fragments, foreign objects mixed in use
The part with foreign matter will cause the effective coil part to be ineffective and only the other parts will be compressed, and the actual effective number of coils will be reduced, causing high stress and breaking near the surface.Do not mix foreign matter in the spring.