Engine frame welding fixture and using method

The invention relates to the technical field of airspace engines, in particular to an engine rack welding fixture and a using method. The engine rack welding fixture comprises an assembly welding platform, a rack small end positioning support, a plurality of large end connector positioning seats, a plurality of servo mechanism connector positioners and a plurality of main stand columns. A plurality of groups of connecting grooves are formed in the assembling and welding platform; each set of connecting grooves comprises a plurality of T-shaped grooves, and the T-shaped grooves are opened in the side face and the upper end face of the assembly welding platform and extend from the side face to the middle of the assembly welding platform. The main stand column, the large-end connector positioning base and the servo mechanism connector positioner are fixedly connected with the assembling and welding platform, and the positions of the main stand column, the large-end connector positioning base and the servo mechan