All major industrial developed countries in the world attach great importance to the role of welding research institutions, basically forming a three-level research and development system of universities, research institutes and enterprises. Major industrial developed countries have set up welding research institutes, such as TWI in Britain, EWI in America, FWI in France, JRWI in Japan and PEWI in Ukraine. They all belong to national welding research institutions.
Welding seam tracking technology is one of the main research directions of welding technology in the future.
Sensor technology provides many possibilities for welding operation. Some have low cost and limited functions, while others require a lot of investment and thoughtful design-its greatest advantage is that it saves the cost in use. On the whole, laser vision welding seam tracking technology is the best welding seam tracking solution at present.
The laser seam tracking system is mainly composed of a laser sensor and a control host. By using the principle of optical propagation and imaging, the position information of each point in the laser scanning area can be obtained, and the online real-time detection of common welds can be completed through complex program algorithms. There are corresponding function settings for the detection range, detection ability and common problems in the welding process. By calculating the deviation between the detected weld and the welding torch, the equipment outputs deviation data, and the motion actuator corrects the deviation in real time, and accurately guides the welding torch to weld automatically, thus realizing the intelligent real-time tracking of the weld in the welding process.
Advantages of optical seam tracking
1. Ensure safe welding and perfect welding seam.
2. Reduce the heat load
3. Improve productivity
4. The welding gun can be in an ideal position.
5. Can compensate the tolerance of production, equipment and operation.
6. For complex weldments, the programming work can be reduced.
7. Consistent and reproducible welding can be achieved.
Comparison between Visual Weld Tracking and Arc Weld Tracking
Except arc tracking, any welding seam tracking solution for the welding process will increase the cycle time, but laser welding seam tracking will increase the minimum time. Usually, the welding seam cycle of each scan is about a quarter of a second, and the increased time can be neglected except for position finding applications. Optical seam tracking can reach 12m per minute at the fastest, so it will not limit the speed of robot or gantry if high traveling speed is required. Laser seam tracking can also be used for processes other than welding, such as cutting, gluing and grinding.
Compared with arc tracking, laser tracking has special advantages, because it does allow equipment to run over parts or off-line. Material inconsistency, such as rust and scale, has little effect on laser welding seam tracking, because tracking is completely based on the imaging of parts.
