Laser arc hybrid welding technology is one of the new technologies vigorously researched and promoted by various industries in recent years. It has a good application prospect with good penetration,small welding heat input,easy control deformation,and has been applied in many fields. The application of laser arc hybrid welding in the medium heavy plate of railway vehicle bogie solves some shortcomings of traditional MAG welding. Combining the structural charac-teristics of the steel tube products for railway bogie beam,the difficulties in radiographic inspection of laser arc hybrid weld of bogie beam steel tube analyzed and solved,the microfocus rod anode technology is used to carry out circumferential exposure detection for laser arc hybrid welding girth weld of steel tube for bogie beam,and it is verified in the actual test,all kinds of defects in the weld can be detected accurately,the main factors affecting the welding quality of laser arc hybrid welding are found. The application of microfocus rod anode automatic radiographic testing technology in the weld inspection of medium heavy plate of bogie steel tube is studied,full coverage of weld is realized and the quality of weld is guaranteed.