Automobile body assembly welding
(1) Resistance spot welding automobile body assembly welding includes frame, floor, side wall, door and body assembly welding, etc. assembly welding, etc., in the welding production process a large number of resistance spot welding process. According to statistics, there are about 3000~4000 resistance spot welding joints on each car body. In the automotive body welding process, the spot welding process is still dominant, and the application of resistance spot welding technology has realized the mass production and automation of automobile body manufacturing.
The resistance spot welding equipment used in the automobile body welding production line mainly has the following three categories:
(1) Hanging spot welding machine is mainly used in positioning welding stations on the body assembly welding production line, or for the welding of parts with complex welding joint positions (not suitable for automation). Manual work, low degree of automation.
(2) The advantages of multi-spot welding special machine multi-spot welding process are high production efficiency and small welding deformation. Its disadvantage is that it cannot be adapted to the production of a variety of models and has poor flexibility.
(3) Spot welding robot Spot welding robot is widely used in the modern body welding production line, which can improve the automation degree of welding production, reduce the labor intensity of operators, improve production efficiency, and ensure welding quality. Spot welding robots are mainly used for body assembly welding repair welding stations, body assembly welding stations, etc. Moreover, due to the use of spot welding robots, the flexible production mode of body welding has been realized – multi-variety, low-batch mixed line production.
Spot welding robots are usually composed of robot body, robot control device, spot welding tongs and resistance welding controller (time controller). Current spot welding robot systems apply the following advanced technologies:
First, the inverter welding power supply reduces the weight and volume of the welding transformer, and the transformer and welding tongs are made into integrated robot spot welding tongs. The application of integrated welding tongs is conducive to the spot welding robot to achieve trajectory movement and attitude change within its range of motion. The use of inverter welding power supply can also improve the electrical performance of the welding machine, improve the thermal efficiency of the power supply, and achieve the purpose of energy saving.
Second, the automatic replacement device of welding tongs standardizes the connection interface between the robot welding tongs and the primary side water and electricity piping through modular design. The device is equipped with several different forms of welding tongs, and the spot welding robot can be automatically replaced in a few seconds according to the program. Realize the rapid and automatic replacement of welding tongs, so as to meet the requirements of welding of various parts of the body with a spot welding robot, and can also adapt to the needs of multi-variety model production.
Third, the robot control system adopts this system not only to control the movement of the robot body, but also to automatically control the resistance welding time controller, issue welding start instructions, automatically control and adjust welding parameters (voltage, current, pressure, time cycle), control the size of the spot welding tongs and clamping and loosening action. At the same time, it also has automatic fault diagnosis, alarm and other functions, such as: electrode adhesion to the welded workpiece, fault alarm when compressed air pressure is too low.
(2) In the production of arc welding automobile body assembly, manual repair welding operations are mainly carried out in the main welding station of the frame, floor, etc., and there is an application of solitary welding robot in the welding station of the sub-frame equal assembly workpiece.
2. Auto parts welding
In the production of auto parts, spot welding, convex welding, seam welding, butt welding and arc welding and other welding processes are widely used. For example: beam assembly bracket spot welding, transmission shaft balance sheet convex welding, automotive fuel tank seam welding, automotive wheel rim continuous flash butt welding, automotive steering arm, muffler, purifier shell arc welding, etc.
In the production of auto parts in China, for many years by manual welding, special machine welding occupies the dominant position of welding production, labor intensity, harsh operating environment, welding quality is not easy to guarantee, and the flexibility of production is also very poor, can not meet the needs of modern automobile production. In recent years due to welding robots. A large number of applications have improved the automation level and production efficiency of parts production, while making production more flexible, and welding quality has also been guaranteed.