Welding Robot Welding Process
Welding industrial robots are mainly used in industries that require high productivity. Generally, spot welding and arc welding can be performed with the help of robots. In addition to resistance spot welding and arc welding processes, two common welding processes used for production purposes are metal inert gas (MIG) welding and tungsten inert gas (TIG) welding.
Welding industrial robots automate the process, ensuring higher precision, less waste and faster operation. With the widespread application of mechanical equipment, welding industrial robots can adapt to a variety of welding processes including arc, resistance and spot welding. One of the more common welding industrial robot welding processes is the arc welding process. Arc welding is a welding process in which metal is fused together by electricity. An arc is formed between an electrode (consumable or non-consumable) and the metal using direct current (DC) or alternating current (AC) current, causing them to melt and combine together.
Resistance spot welding process: Resistance spot welding is a welding process in which two formed copper alloy electrodes are used to concentrate the welding current into a point while joining the sheets together. The high current forced into a point causes the metal to melt and form a weld. By using high current at a specific location, the rest of the sheet is not heated during the welding process.
Spot welding process: Some materials can resist the current, making them inaccessible to other forms of welding. This often occurs in the automotive industry to assemble parts of the car body. To overcome this problem, welding industrial robots use a variation of the resistance welding process to join a pair of thin metal sheets at a point.
Visual seam tracking system for pipeline welding robots
A seam tracking system based on the generation of visible light is proposed for use in pipeline welding robots. First, a visual sensor is designed based on the analysis of the effect of laser reflection on the welding surface and the position of the camera, the plane where the laser is located, and the image of the laser stripes after welding. To prevent severe reflection disturbances in the weld image, image processing and feature extraction algorithms are developed. For seam tracking of pipeline welding, an image vision control system is adopted. The performance of this system is verified by controlling the seam tracking experiment of the pipeline welding robot.
Weld seam tracking is one of the important issues related to robot welding, and it is also the basis for high-quality automated welding. Industrial welding robots are mostly used for teaching, and the robot repeats this path to meet the position requirements of the beam during welding. There are some problems in this mode of welding robots, such as inaccuracy in the welding position, deformation and distortion of the weld caused by heat diffusion. These problems cause the beam to deviate from its theoretical welding path, so it is necessary to control the weld trajectory of the beam during welding. Secondly, the pipe welding robot cannot pre-define the weld because the weld may deviate from the position inside the pipe when the pipe changes direction. The weld trajectory can change as the pipe moves in the axial direction. In this case, this mode is not suitable for pipe welding, and the welding robot needs to correct the offset between the beam and the weld when welding in time.
In order to avoid the deviation of the weld when moving the pipe, the solution is to use a three-degree-of-freedom multi-manipulator to lift the pipe, adjust the position of the pipe, and straighten the direction of the pipe. When the pipe changes direction, the weld will deviate from its original position, and then a weld tracking system is required for high-quality welding.