Automobile manufacturing includes four processes: stamping, welding, coating and final assembly. Firstly, the steel plate is stamped into body parts by stamping, the stamped body parts are connected by welding, the body is sprayed with paint through the coating process, and finally the body, interior trim, chassis and tires are assembled into the whole vehicle.
1、 Stamping process
Stamping process is the first step of automobile manufacturing, and each part corresponds to a forming die. The forming die is installed on the stamping machine. During stamping, the blank with appropriate size has been cut on the cutting machine, and the workpiece shape is formed in the die. 60% ~ 70% of the parts of the automobile are formed by stamping.
2、 Welding process
Welding process is the process of heating and pressurizing the stamped body parts locally or as a whole, so as to realize the assembly of each stamped part of the body. Welding is the key part of body forming, which ultimately determines the overall strength of the body. The welding process usually includes bottom plate assembly, side wall assembly, rear wall assembly, top cover assembly, door assembly, luggage compartment assembly, etc. The body assembled through the welding process is the BIW.
3、 Coating process
The typical body coating process is electrophoresis primer and medium finish 3C3B system, which mainly includes three processes: pretreatment before paint, primer, painting process and drying process. Through a large number of chemical reagent treatment and process parameter control, the corrosion resistance of the car body is enhanced, and the overall beauty of the car body is also increased.
4、 Assembly process
The final assembly process is the final link of automobile manufacturing. It is the assembly process of tens of thousands of parts such as body, engine, door, instrument panel and lamp that have passed the inspection according to the accuracy and technical requirements. The operation contents include interference fit, welding, riveting, inlay, wiring, threaded connection, etc., accounting for about 20% ~ 25% of the overall workload.
According to the four processes of automobile manufacturing, automobile manufacturing equipment can be divided into four production lines: stamping automation production line, body welding and assembly automation production line, coating and spraying automation production line and automobile assembly automation production line.
Customers in the automotive manufacturing equipment market are mainly divided into three echelons:
The first echelon is the high-end brand vehicle manufacturers represented by Porsche and Mercedes Benz. The production line automation rate of these enterprises is high, and the automation rate of BMW and Mercedes Benz can reach 99%. Their suppliers have a high entry threshold and high business gross profit margin. At this stage, they are mainly occupied by foreign enterprises such as coma, abb and FFT.
The second echelon is the pure foreign capital represented by German Volkswagen and American GM, as well as the Sino foreign joint ventures represented by Shanghai Volkswagen, SAIC GM and Dongfeng Nissan. Both foreign and domestic suppliers participate in the competition, followed by the threshold and business gross profit margin.
The third echelon is the domestic brand vehicle manufacturers represented by JAC and Chang'an. The production line automation rate is low, and the production automation rate of Chang'an is about 50%. Its supplier threshold is low, the payment collection time is long, and the gross profit margin is low. In 2013, coating equipment and welding equipment accounted for 34.93% and 24.72% of the four major processes of automobile manufacturing equipment in China, respectively. In 2014, the overall market scale of China's automobile manufacturing equipment was 130 billion yuan, with a year-on-year increase of 13.54%. In 2015, the overall market scale reached 159.3 billion yuan.