Square tube welding limiting device

The utility model discloses a square tube welding limiting device. At present, when a beam body is vertically welded, it needs to be guaranteed that a cross beam and a longitudinal beam are always perpendicular in the whole welding process, spot welding fixing is needed after the cross beam and the longitudinal beam are vertically erected, the cross beam often falls off, and much inconvenience is brought to the welding process. The square tube welding limiting device comprises angle steel (1) and channel steel (2), the end of the horizontal plate face of the angle steel is perpendicularly and fixedly connected with the outer side of the long plate face of the channel steel, the horizontal plate face of the angle steel and the top end tangent plane of the channel steel are located on the same horizontal plane, and a large-diameter threaded hole (3) is formed in the middle of the vertical plate face of the angle steel. A large-diameter threaded rod (4) is screwed into the large-diameter threaded hole, the botto