Multipurpose diagonal welding tool

A multipurpose diagonal welding tool comprises a bottom plate, two long grooves are formed in the bottom plate in a right-angle mode, each long groove is provided with a pipe fitting clamping and positioning device, each pipe fitting clamping and positioning device comprises a plurality of parallel rotating shafts rotationally installed on the two groove edges of the corresponding long groove, and each rotating shaft is fixedly connected with a U-shaped supporting rod. Each rotating shaft on the inner side of each long groove is fixedly connected with a linkage arm, each linkage rod is hinged to the corresponding linkage arm through a hinge shaft parallel to the corresponding rotating shaft, a datum plate is installed on the outer side edge of each long groove, and the groove edge of each long groove and the bottom plate of the corner formed by the two long grooves are each provided with a set of rapid jacking mechanism. The device can be used for welding two pipe fittings with the same pipe diameter and can