If the workpiece does not need to be displaced during the whole welding process, it can be positioned on the workbench with a fixture. This system is the simplest. However, in actual production, more workpieces need to be moved during welding, so that the weld can be welded in a better position (posture). In this case, the positioner and the robot can move separately, that is, the robot is welded again after the positioner is displaced; It can also move at the same time, that is, the positioner moves when the robot is welding, which is often said that the positioner and the robot move in coordination. At this time, the movement of positioner and robot is combined, so that the movement of welding torch relative to workpiece can meet the requirements of welding trajectory, welding speed and welding torch posture. In fact, the axis of the locator has become a part of the robot at this time. This welding robot system can have 7-20 axes, or more. The latest robot control cabinet can be a combination of two robots 12 axes for coordinated movement. One of them is a welding robot, and the other is a handling robot used as a locator.
If the welding robot workstation is further subdivided, the following four types can be obtained:
1. 1 box welding robot workstation is a special equipment specially developed for box welding with high output and high welding quality and size requirements in box industry.
The box welding robot workstation consists of arc welding robot, welding power supply, welding gun wire feeder, rotary double-station positioner, fixture and control system. This workstation is suitable for welding all kinds of box-shaped workpieces. In the same workstation, automatic welding of various boxes can be realized by using non-stop fixture, and the welding position is high. Due to the adoption of the two-position positioner, while welding, other stations can disassemble and assemble the workpiece, which greatly improves the welding efficiency. Because MIG pulse transition or CMT cold metal transition welding process is used for welding, the heat input in the welding process is greatly reduced, and the products are not deformed after welding. By adjusting the welding specification and robot welding posture, the weld quality of the product is good and the weld is beautiful, especially for the stainless steel gas chamber with high sealing requirements, and the gas in the gas chamber will not leak after welding. By setting the variety selection parameters in the control system and replacing the working fixture, the automatic welding of multiple variety boxes can be realized.
The workstation can meet the welding requirements of various boxes with weld length of about 2000 mm, and the welding speed is 3 3- 10 mm/s 0 mm/s. According to the basic material of the box, different types of gas shielded welding are used in the welding process. The workstation is also widely used in electric power, electric power, machinery, automobile and other industries.
1.2 stainless steel gas chamber robot flexible laser welding processing equipment is a flexible robot laser welding processing equipment developed for welding box-shaped workpieces with large welding deformation and high sealing requirements. The processing equipment consists of robot, laser generator set, water cooling set, laser scanning and tracking system, flexible positioner, fixture, safety guardrail, dust suction device and control system. By setting the variety selection parameters and replacing the fixture in the control system, the automatic welding of multi-variety stainless steel gas chamber workpieces can be realized.
1.3 axis welding robot workstation is a special equipment specially developed for shaft welding of universal circuit breaker in low-voltage electrical appliance industry. A set of special shaft welding robot workstation is introduced.
The workstation of shaft welding robot consists of arc welding robot, welding power supply, welding gun wire feeder, rotary double-station positioner, fixture and control system. This workstation is used for welding various workpieces based on rotating shafts (with multiple cantilevers on it), and automatic welding of various rotating shafts can be realized by using different fixtures in the same workstation. The welding position accuracy is very high. Due to the adoption of the dual-position positioner, other stations can disassemble and assemble the workpiece while welding, which greatly improves the efficiency.
Technical indicators: the diameter of the rotating shaft is Ф10-50 mm, the length is 300-900 mm, the welding speed is 3-5 mm/s, the welding process adopts MAG mixed gas shielded welding, and the positioner rotates, and the positioning accuracy reaches 0.05 mm ..
Widely used in high-quality and high-precision welding of various workpieces with rotating shafts, and suitable for electric power, electric power, machinery, automobile and other industries. If the rotating shaft is welded by manual arc welding, the labor intensity of workers is extremely high, the product consistency is poor, and the production efficiency is low, with only 2-3 pieces per hour. After using the automatic welding workstation, the output can reach 15-20 pieces/hour, and the welding quality and product consistency are greatly improved.
Low-voltage electric rotating shaft of shaft welding robot workstation
1.4 robot welding stud workstation
Robot welding stud welding workstation uses robots to weld studs of different specifications on complex parts to workpieces. The workstation is mainly composed of robot, stud welding power supply, automatic nail feeder, robot automatic stud welding gun, positioner, fixture, automatic gun changing device, automatic detection software, control system and safety guardrail. The studs are sent to the robot automatic welding gun through the automatic nail feeder, and the studs with different specifications are welded to the workpiece by programming the path taught by the robot on the workpiece. The stud can be firmly welded to the workpiece by energy storage welding or arc welding to ensure welding accuracy and welding strength. The welding efficiency is about 3- 10 pieces/minute, and the stud size is 3-8mm in diameter and 5-40mm in length.
Welding robot production line
The production line of welding robot is relatively simple, and multiple stations (units) are connected by a workpiece conveying line to form a production line. This production line still maintains the characteristics of single station, that is, each station can only weld the predetermined workpiece with the selected workpiece fixture and welding robot program, and the production line cannot weld other workpieces for a period of time before replacing the fixture and program.
The other is welding flexible production line (FMS-W). The flexible line is also composed of several stations, but the difference is that the welded parts are all clamped on a unified tray, and the tray can cooperate with the positioner at any station on the line to automatically clamp. Firstly, the welding robot system recognizes the serial number of the pallet or workpiece, and automatically calls the welding program of the workpiece for welding. In this way, each station can weld different workpieces without any adjustment. Generally, the welding flexible line has a rail car, which can automatically take the fixed workpiece out of the storage station and send it to the positioner of the welding robot workstation with vacancies. The welded workpiece can also be removed from the station and sent to the outflow position of the finished product. The whole flexible welding production line is controlled by dispatching computer. Therefore, as long as enough workpieces are assembled during the day and put on the storage station, no one or fewer people can produce them at night.
Which automatic welding production form the factory chooses must be determined according to the actual situation and requirements of the factory. Special welding machine is suitable for products with large batch and slow modification, and the number of welds on the workpiece is small and long, and the shape is regular (straight line, round); Welding robot system is generally suitable for small and medium-sized batch production, and the welds of the workpiece to be welded can be short and many, and the shape is also more complicated. Flexible welding line is especially suitable for many kinds of products and few quantities in each batch. At present, foreign enterprises are vigorously promoting JIT management mode without (less) inventory. In this case, the flexible welding line is more suitable.
Application of welding robot in automobile production
At present, welding robots have been widely used in automobile manufacturing, such as automobile chassis, seat frame, guide rail, muffler, hydraulic torque converter and so on, especially in automobile chassis welding production. Toyota has decided to take spot welding as a standard and equip all its spot welding robots in Japan and overseas. This technology can improve the welding quality, and even try to use it instead of some arc welding operations. The movement time in a short distance is also greatly shortened. The company recently introduced a low-altitude spot welding robot for welding the lower part of the car body. This short spot welding robot can also be assembled with a higher robot to process the upper part of the car body, thus shortening the length of the whole welding production line. Domestic production of Santana, Passat, Buick, Sail, Polo and other rear axle, sub-frame, rocker arm, suspension, shock absorber and other automobile chassis parts are mostly stress safety parts based on MIG welding process. The main parts are stamped and welded, with an average thickness of1.5 ~ 4 mm. The welding is mainly in the form of lap joint and fillet joint, which requires high welding quality, and its quality directly affects the safety performance of the automobile. After robot welding, the appearance and internal quality of welded parts are greatly improved, which ensures the stability of quality, reduces the labor intensity and improves the working environment.