Positioning device for welding

The utility model relates to the field of welding processing, and discloses a welding positioning device which comprises a working plate, the top of the working plate is slidably connected with two clamp shells, the interiors of the two clamp shells are rotatably connected with first threaded rods, and the peripheries of the first threaded rods are in threaded connection with two clamp hands. The middle of the first threaded rod is rotatably connected with a first fixing block, the rear end of the clamp shell is fixedly connected with an extension shell, the interior of the extension shell is in threaded connection with a second threaded rod, the middle of the second threaded rod is rotatably connected with a second fixing block, the top of the working plate is fixedly connected with a motor, and the output end of the motor is fixedly connected with the second threaded rod. A lifting assembly is arranged at the bottom of the working plate. According to the welding device, through cooperation of the first thre