The positioner is mainly used to fix the workpiece on the work surface for rotation and tilting, so that the welding seam is in the most favorable welding position to improve welding quality and productivity. The work surface can be tilted from 0° to 120°, and can be continuously rotated 360° at any position (stepless speed regulation). It is especially suitable for welding various welding parts with circumferential welds, and is extremely ideal and convenient welding equipment.