Welding robots are promoting the development trend of welding automation

1. The advantages of welding robots in automated production

From the birth to the present, robots are mostly used in the welding field. According to statistics, by the end of 2007, the total number of welding robots installed in the world had reached nearly 40,000. As a kind of advanced welding equipment, welding robots have been widely promoted, which is an important sign that the welding industry of our country has entered the era of automation.

With the advancement of science and technology, people have higher and higher requirements for welding quality. Automated production requires reducing manpower, improving product consistency, and improving product quality, making it more suitable for mass production, reducing production costs, and improving production efficiency. In manual welding, it is difficult to maintain the stability and consistency of the welding work for a long time due to the influence of objective and subjective factors such as technical level, fatigue degree, sense of responsibility, physiological limit, etc. Moreover, due to the poor working conditions of welding, the number of people willing to do manual welding is decreasing, and there is a tendency for a shortage of skilled workers. It can be said that welding robots largely meet the requirements of welding automation, and the advantages of automated production can be summarized as the following:

(1) Stabilize and improve the welding quality to ensure its uniformity. Welding parameters such as welding current, voltage, welding speed and dry elongation have a decisive effect on welding results. When using robot welding, the welding parameters of each welding seam are constant, and the quality of the welding seam is less affected by human factors, which reduces the requirements for the operation technology of the workers, so the welding quality is stable. In manual welding, the welding speed, dry elongation, etc. are all changed, and it is difficult to achieve uniform quality.

(2) The product cycle is clear and it is easy to control the product output. The production cycle of the robot is set at the same time, so the production plan is very clear.

(3) Improve labor productivity. The robot can be produced continuously for 24 hours. With the application of high-speed and high-efficiency welding technology, the use of robot welding has improved efficiency more significantly.

(4) Improved working conditions. With robot welding, workers only need to load and unload the workpiece, which is far away from welding arcs, fog and splashes. For spot welding, workers do not need to carry heavy manual welding tongs, freeing workers from high-intensity manual labor.

(5) Shorten the cycle of product modification and replacement and reduce the corresponding equipment investment. The welding automation of small batch products can be realized. The big difference between a robot and a special machine is that the program can be modified to adapt to the production of different workpieces.

2. System development

The development of electronic technology, computer technology, numerical control and welding has provided favorable conditions for the automation of the welding process, and has penetrated into all fields of welding. Strictly speaking, welding is a welding robot system or workstation, including the robot body, robot control cabinet, welding machine system and wire feeding unit, positioner, assembly and other components. The typical welding robot system has three forms: welding robot workstation, welding robot production line, welding special machine. Welding robot workstations are generally suitable for medium and small batch production. The welding seam of the welded workpiece can be short and many, and the shape is more complicated. The welding robot production line is especially suitable for use in the case of a large variety of products and a small number of each batch; special welding machine It is suitable for products with large batches and slow modification. It is also more suitable for workpieces with fewer welds, longer welds and regular shapes. Which type of automated welding production to choose depends on the actual situation of the company.

3. Problems and solutions of welding robot automation application

At present, the welding robot in application is still "teaching reproduction type", its welding path and process parameters are preset, and the consistency of operating conditions is very strict, and it lacks external information sensor feedback and real-time feedback during the welding process. Adjustable function. However, changes in the environment and conditions in the actual welding process are inevitable, such as the dispersion of joint positions, weld gaps and dimensions caused by welding workpiece processing and assembly errors, the difference between the teaching track and the actual weld, and the welding process Factors such as thermal deformation, penetration and unstable weld formation will cause fluctuations in welding quality and lead to welding defects. In order to overcome the influence of various uncertain factors in the welding process on the quality of precision welding, it is urgent to adopt information feedback, intelligent control and other technologies to improve the adaptability or intelligence level of the current welding robot, so that it can realize the initial welding position recognition and autonomy Guidance, real-time welding seam correction and tracking, acquisition of dynamic feature information of welding pool, adaptive adjustment of process parameters and real-time control of welding seam formation, that is, to realize the autonomous intelligent control of the robot welding process, thereby making up for the welding robot’s automatic welding insufficient.