Regarding the selection of the positioner arm length of the arc welding robot, there are two problems. One is that the cutting accuracy is low and cannot meet the requirements; the other is the accuracy of the assembly equipment. Due to the thermal deformation of the cutting material, the slab error of the weldment is relatively large. In the next process, pairing and blanking are performed on a low-precision lap welding die. In this way, the weld billet produced cannot meet the teaching accuracy requirements.

If a welding work unit consists of an arc welding robot and one or two welding positioners, the transmission accuracy of the peripheral equipment is required to be high. For example, the transmission accuracy of the positioner is required to be 1 meter in diameter with a tolerance of ±0.2 . The ordinary slewing bearing, the radial runout of 1 meter diameter, and the transmission clearance of the ordinary reducer exceeding 0.01mm can meet the demand.

Although the welding positioner of the arc welding robot has 4-6 axes, its welding gun can reach any point in the working range to weld the weldment with the required posture, but in actual operation, for some complicated weldments , If it does not change its position in time, it may interfere with the welding torch, making the welding torch unable to weld along the set path.

In addition, in order to ensure welding quality and improve production efficiency, the arc welding robot welding positioner often needs to adjust the welding seam to a better position such as level and ship shape for welding. Therefore, it is also necessary to change the position of the weldment in a timely manner. Based on the two reasons mentioned above, almost all positioners appear as a complete set, among which the turning machines, positioners and turntables are mostly.