Positioning mechanism for metal material welding machining

The utility model discloses a positioning mechanism for metal material welding processing, which comprises a working table, a guide groove is arranged at the center of the top of the working table, a screw rod is arranged in the guide groove and penetrates through the working table, the screw rod is connected with the working table through a working bearing, the input end of the screw rod is fixedly connected with a hand-cranking disc, and the hand-cranking disc is fixedly connected with the working bearing. Two sliding plates are symmetrically arranged in the guide groove, the cross section of each sliding plate is in a T shape, screw holes matched with the lead screws are formed in the sliding plates, two sets of vertical plates are symmetrically arranged at the tops of the sliding plates, the number of each set of vertical plates is two, and the two vertical plates are connected through a bearing plate. A limiting clamping groove is formed in the top of the bearing plate, and a cylinder is connected into t