1 automobile suspension spring. Total amount of steel suspension springs used
There are two kinds of springs used in automobile industry: leaf spring and suspension spring (also called spiral suspension spring).
Automobile round spring is made of 9 16mm diameter steel bar and wound with various cold-drawn steel wires; In addition, some mini-cars, suspension spring vans and motorcycle shock-absorbing springs also adopt four seasons like spring.
Leaf springs for light trucks, medium trucks and buses, with the size of 630× 50 140mm, are flat steel varieties. Trucks generally use prismatic steel springs for heavy vehicles, such as the back of the spring and the front of the reed section. Cars generally use variable cross-section leaf springs. It is difficult to produce cones, and only British equipment imported from Dongfeng with production capacity is available in China.
The development of automobile industry will determine the number of leaf springs and spring wheels. According to statistics, by the end of 2004, nearly 50 enterprises had jointly produced about 500,000 tons of suspension springs, equivalent to about 550,000 tons of steel springs, accounting for 90% of the total. Therefore, the total demand of automobile suspension in China is about 600,000 tons, of which the required spring steel refers to flat steel springs and spring steel wires of about 40,000 tons.
2。 Steel consumption
According to the introduction of suspension spring by Dongfeng Motor Co., Ltd., the weight of leaf spring on the front axle of a 5-ton truck (140) is about 50kg, leaf spring on the rear axle is about 5060kg, and leaf spring on the auxiliary axle (including the above rear axle) is about 7080kg. According to the 90% steel utilization rate, a 5-ton truck needs 200300kg.
The weight of leaf spring on the front axle of an 8-ton truck (model 153) is about 90kg, the weight of rear axle of leaf spring is about 90 100KG, and the weight of auxiliary leaf spring shaft is about 7080kg. In addition, to calculate the steel utilization rate of 90%, the leaf spring of a 5-ton truck needs about 300kg.
/kloc-a 0/3 ton heavy truck needs about 400 kilograms of leaf springs.
Take a bus with four suspension springs as an example. The average leaf spring of a car is about 200,300 kg.
Cars with four suspension springs (front and rear 2), such as cars with spring steel wires, average about 15kg.
3。 Suspension spring steel with steel, specifications and requirements
(1) spring flat steel
Light trucks, medium and heavy vehicles and buses use steel and steel springs as follows:
The typical specifications of 60Si2Mn steel are:10× 60 (65,75,90, 1000)mm,1× 60 (70,75) mm, and the specifications of square steel springs are/kloc-0.
Specifications of 55SiMnB spring flat steel: 10× 75mm, 1 1×70(90) mm, 12×70, 12× 90mm,13× 90mm.
50CrVA adopts the standard 12× 90mm, and the annual consumption accounts for about 30%.
In addition, less -65Mn steel is used, with the representative specification of 10× 75mm, 35CrMnSi 10× 75mm and 60CrMnA 12× 60mm. The leaf spring is also the flat steel of several manufacturers, 70 # Q235 cold-drawn steel wire. Q235 flat steel is used for connection, with specifications of 4× 25mm, 5× 25mm and 6× 30mm. 70 # cold-drawn steel wire drum, cut into heat treatment to remove iron sheet and regenerate. Wire specifications are fine particles sprayed on the surface of steel plate after1.2 mm.
(2) Spring steel
Cars, as well as some mini-cars, suspension spring vans and motorcycles are made of round spring steel 60Si2MnA steel, 55CrSi(SUP 12) and 50GrVA.
There are four automobile suspension springs, and the front and rear universal ends are slightly smaller than the rear ends. What are the sizes of all models used in different calibers? 916mm.
The automobile suspension spring wire made of stainless steel spring wire is advanced, requiring high strength and long fatigue life. The effect is that the spring steel wire has good damping characteristics, composition, shape and quantity distribution, so it requires chemical inclusions, high surface quality, decarbonization, microstructure and mechanical properties. The surface decarburization of spiral spring is required to be less than 0.5% of the diameter. On the polished surface, there should be longer fatigue life and stricter dimensional tolerance, and there should be no defect transmission. Commonly used thermal processing methods are usually difficult to meet the requirements of users. Therefore, hot forming and cold forming of automobile suspension coil springs are gradually replaced by stretching and heat treatment (quenching and tempered martensite transformation). The development direction of suspension spring steel is to reduce carbon content, reduce decarburization tendency and increase flexibility and attenuation resistance of plastic forming.
4。 Mainly supply domestic steel producers.
(1) Major domestic producers of flat spring steel
At present, the annual demand is about 560,000 tons of raw materials, and the quality, varieties and specifications of domestic spring flat steel. In order to meet the basic needs of users, taking Dongfeng Motor Leaf Spring Co., Ltd. as an example, we mainly purchase all domestic spring flat steel from Rong Iron and Steel Co., Ltd., Jiangxi Changli Automobile Spring Co., Ltd., Daye Special Steel Co., Ltd. and Jiangyin Xingcheng Iron and Steel Co., Ltd. At present, the domestic companies that can produce spring flat steel are summarized as follows:
Jiangxi Changli Automobile Spring Co., Ltd.: Located in Nanchang City, Jiangxi Province, Nanchang Iron and Steel Co., Ltd. is a subsidiary of Jiangxi Automobile Leaf Spring Co., Ltd., a holding company. Through capital increase, share expansion and standardization reorganization, it has established joint-stock companies with jiangling motors Group Co., Ltd. in Guangzhou, Jiangxi Rao Xinjiang Industrial Group and Jiangxi Imported Automobile Parts Co., Ltd. * *, and is a member of China Automobile Parts Industry and Trade Group and a designated manufacturer of automobile parts in China. Japan's main production equipment introduces flat steel springs with an annual output of 60,000 tons. Single slot flat plate 3 10 #, flat steel spring flat steel specification (522)×(50 120)mm, length 4.8 mm, material 55Si2Mn, 60Si2Mn steel, 55SiMnVB, 55SiMnoBRe, 50CrVA, etc.
Xinjiang Bayi Iron and Steel Co., Ltd.: The main products are spring flat steel (including double groove and T-shape). When the specification is 6×5020× 100mm, the length is 69 meters and the annual output is about 60,000 tons.
Sichuan Chuanwei Iron and Steel Group Co., Ltd.: The main products are spring flat steel with specifications of (50 120)×(530) mm, 60Si2Mn steel, 55SiMnVB and 60CrMnA.
Fushun special steel co., ltd: the main products are 625× 60 120mm spring flat steel products.
Chuandong Sichuan Automobile Parts Manufacturing Co., Ltd.: mainly produces automobile leaf springs, rolled flat steel wheels and suspension parts of various specifications of automobiles and automobile springs. 654.38 million tons of cold-rolled flat steel springs were used for automobiles, and 30,000 tons of automobile leaf springs were produced.
Shenyang Dongyang Iron and Steel Co., Ltd.: Main products: (620)×(80 120)mm spring flat steel, 55SiMn steel and 60Si2Mn steel.
Daye Special Steel: The production capacity of spring flat steel can reach 654.38+10,000 tons.
Zhengzhou Yongtong Special Steel Co., Ltd.: The main products are spring flat steel and spring reinforcement, with five flat steel specifications ranging from 20mm to 50150 mm.
Huaigang Group: produces various specifications of spring flat steel, mainly made of 60Si2Mn steel and 55SiMnVB, with an annual output of 20,000 tons.
(2) The main situation of spring steel wire production in China.
At present, the raw material of automobile spring steel wire is about 40,000 tons, but the varieties and specifications of domestic spring steel wire can't meet the requirements of users, especially the spring steel wire used to support the demanding automobile suspension needs to be imported from abroad. The main importing countries are Japan, South Korea, Sweden and France.
In recent years, many banks such as Zhengzhou Dihua, Tianjin Dihua, Changsha Fenling, Nanjing Suzhou, Shanghai Song, etc. It has been adopted by domestic companies and enterprises such as Kobe Steel and Sumitomo in Japan. The steel used is 60Si2MnA steel, 55CrSi(SUP 12) and 50GrVA. Compared with Japan and South Korea, the quality of domestic products is still very backward. Compared with similar products, the price is relatively low, providing motorcycle accessories such as mini-cars, van suspension springs and shock absorber springs for some spring factories.
Today, the main producers of alloy spring steel wire are Baosteel, Shougang Special Steel, Dalian Special Steel and Shanghai No.5 Iron and Steel Plant. Baosteel and Shanghai Iron and Steel No.5 Plant have quality advantages, but their prices are relatively higher than those of other steel mills. Baosteel high-speed wire rod spring steel wire factory has brands such as 55SiCr, 50CrV and 60Si2MnA steel, among which 55SiCr spring steel wire has been drawn, heat treated and heat treated, and the spiral spring has been used with Mazda, Changan, Santana, Jetta and Fukang cars.