Abstract: According to rock cross-cut coal uncovering under the condition of high ground pressure and high gas pressure in the depths of Daxing Coal Mine, it used high pressure rotating sealed joint and three wings reaming bit, it used the drilling rig to drive drilling pipe rotating, so that reaming drilling bit rotated to carry out high pressure water jet reaming, which strengthened pressure relief for gas pumping-exhaust. The technology and equipments were suitable for various angle drillings, coal cuttings discharged smoothly while the drilling was being reamed, remarkably improved the effects of coal drillings pressure relief and gas pumping-exhaust, it had important value for extending application.