大口径瓦斯地质孔钻探技术

Drilling Technology for Large Diameter Gas Geology Hole

摘要:

运用非平衡钻探工艺理论，对煤矿瓦斯地层进行大口径钻孔的钻探，使目标层富集的高压瓦斯经抽放后得到释压，确保煤矿安全生产。在针对小构造带形成的角砾岩、松散煤层、不稳定地层等瓦斯地质条件下，采用中压风作为冲洗介质进行钻探中所存在的问题，重新设计了新型的钻具级配、正反向一体化钻头等，并且对风介质的排渣机理进行了阐述和分析。同时，就实践中遇到的问题和解决方法进行了总结。

Abstract:

To ensure the coal mining safety, drilling with large diameter in gas formations and then discharging gas by draining through borehole in gas rich formations, the non-balance drilling conception was used. In allusion to the problems existing in using medium pressure air as drilling fluid under the conditions of breccia formed by small structural action, loose coal layer and unstable formations, new type of drilling tools and bits was designed. The mechanism of cutting removal by air media was stated and analyzed. Meanwhile, the problems occurred in practices and their resolving methods were concluded.