Abstract: According to the problems of drilling equipment in soft-extrude coal seam with insufficient drilling and accident treatment ability,large volume and poor integration,the ZDY5000RF high-power two-track crawler drilling rig is developed,combined with the need of gas drainage borehole construction in soft-extrude coal seam.The drilling rig uses two departments and safety layout,crawler drive walking,so the safety protection system and protection measures are increased,the whole machine power reaches 75 kW,the rate torque reaches to 5 000 N·m,and the pulling force is up to 210 kN.The field test is conducted in Qinan Coal Mine in Huaibei City,in the soft-extrude coal seam,the f value is about 0.5,five drill holes is completed with the depth is more than 200 m.The test results show that the drilling rig can meet the requirements of 200 m gas drainage drilling in soft-extrude coal seam based on the significant advantages of high power,small volume,easy removal,high safety,high drilling and accident processing capability,therefore,it can provide equipment guarantee for coal gas disaster controlling in soft-extrude coal seam.

Key words: Soft-extrude coal seam, All-hydraulic drill, Two-departments layout, High-power