软煤气动螺杆钻具定向钻进技术与装备

针对软煤钻进成孔深度浅、钻孔轨迹不可控、易出现瓦斯抽采盲区等问题,发明了气动螺杆钻具定向钻进技术,开发了由气动螺杆钻具、窄体定向钻机、随钻测量系统等组成的煤矿井下气动定向钻进技术装备。其中,气动定向钻进工艺和完孔技术,解决了松软煤层顺层定向钻孔长距离安全成孔和可靠护孔难题。在淮南某矿进行试验,试验钻孔30个,最大孔深300 m,平均见煤率92.9%,并全孔段安设筛管;钻孔抽采瓦斯纯量32万m^3,试验区域煤巷平均掘进效率9.3 m/d,实现覆盖区域煤层安全高效回采。该技术的成功研发探索出软煤横穿工作面递进式瓦斯治理新模式。

Directional drilling technology and equipment of pneumatic screw motor in soft seam

Aiming at the drilling problems of shallow depth, uncontrollable trajectory and blind area of extraction in soft coal seam, the directional drilling technology of pneumatic screw motor was invented, and the directional drilling equipment consisting of pneumatic screw motor, narrow structure directional drilling rig and MWD system were formed. The air directional drilling technology and hole-completion technology were studied and developed. The technology of drilling and hole-completion solves the problem of long-distance safe drilling and hole protection of directional drilling along soft coal seam. The technology has been successfully tested in a coal mine, Huainan, with 30 test boreholes with a maximum depth of 300 m, an average of coal-drilling rate of 92.9%, and screen pipes installed in the whole hole section, extraction gas volume of boreholes is 320 000 m3, and the average efficiency of coal roadway excavation in the test area is 9.3 m/d, achieving efficient and safe recovery of coal seams in the covered area. A new progressive gas control model of soft coal across working face has been preliminarily explored.