突出煤层钻孔施工防瓦斯超限技术及装备

Technology and equipment of preventing gas overrun in drilling operation of outburst coal seam

针对穿层钻孔施工(水力冲孔)期间瓦斯喷孔的问题,分析确定了水力冲孔作业期间容易引起作业空间瓦斯超限的因素,从解决孔口-防喷装置、钻杆-防喷装置、集气箱排渣处、钻杆水尾等关键地点的密封问题入手,研发了孔口防喷装置,并通过分源抽采自动控制解决抽采能力的合理匹配;防喷装置创新性的采用皮垫-毛刷综合密封,起到了良好密封效果;配套设计了瓦斯缓冲装置,能够起到缓冲、储存瓦斯的作用,有效降低防喷装置内瓦斯冲击压力;同时,根据现场反馈情况从尺寸、材料等方面进行不断优化,提高防喷装置的轻便性及耐用性,形成了完善的穿层钻孔施工(水力冲孔)防超限技术及系列化装备。

Aiming at the problem of gas gushing hole during the construction of through layer drilling(hydraulic punching), the factors that easily cause gas overrun in the working space during the hydraulic punching operation are analyzed and determined.Starting from solving the sealing problems of the key points such as the orifice blowout preventer, drill pipe blowout preventer, gas gathering box slag discharge place and drill pipe tail, the blowout prevention device at the orifice is developed, and the automatic control of separate source drainage is adopted to solve the reasonable matching of pumping capacity. The blowout preventer innovatively adopts the integrated seal of leather pad and brush, which has a good sealing effect. The gas buffer device is designed to buffer and store gas, and effectively reduces the gas impact pressure in the blowout preventer. At the same time, according to the feedback from the site, the size, materials and other aspects are continuously optimized to improve the portability and durability of the blowout preventer, forming a perfect anti-overrun technology and series of equipment for cross layer drilling construction(hydraulic punching).