Abstract: ZDY20000LK large diameter pressure relief drilling rig is developed to solve the problem that the large diameter pressure relief drilling hole of coal bump can only meet the expected pressure relief requirements through the construction technology of one drilling hole and multiple reaming. The drill has the function of automatic loading and unloading drill pipe and 800m remote control. It can improve the safety and reduce the labor intensity of workers during construction. The project also studied the drilling rig with φ 260mm large spiral insert drill pipe and φ 300mm tower PDC bit, which can meet the requirements of coal side pressure relief drilling with a diameter of 300mm. The industrial test shows that the average drilling efficiency of the drill reaches 10min/m and the maximum hole depth is 81m, which fully verifies the reliability and stability of the rig structure, hydraulic system and remote control system. Electromagnetic CT detection shows that the large diameter pressure relief boreholes weaken the coal body, so that the impact risk of coal body in the abutment pressure area of the roadway is significantly reduced, and the smaller the spacing of pressure relief boreholes, the better the pressure relief effect. The research results can be used as reference for the development of large diameter pressure relief drilling equipment and the construction of rock burst pressure relief drilling.