In view of the problems of difficult gas control, low construction efficiency and serious waste of water resources in the soft layer at the bottom of the coal seam in the construction of bedding hole in the heading face of Xinjing Coal Mine, this paper studies and develops a set of high-efficiency mechanical drilling and expansion and automatic unloading drill pipe complete equipment. The equipment mainly includes low-hole high-torque hydraulic drilling rig, mechanical-hydraulic integrated cavitation device, sewage circulation treatment equipment, etc., which can realize functions such as automatic construction, adaptive drilling, and sewage recycling. Through two rounds of industrial tests, it is verified that the equipment has significant effects in improving construction efficiency, reducing labor intensity and reducing waste of water resources. The test results show that the automatic construction function of the equipment reduces the number of single-shift construction personnel from 4 to 2, the construction efficiency is increased by about 34 %, and the sewage recycling rate is more than 60 %, which effectively solves the problem of cinder water treatment. The successful application of this equipment provides efficient and safe technical support for gas control in Xinjing Coal Mine, and has wide application value.