钻天山矿区Φ219mm大口径金刚石单动双管钻探施工技术

Φ219 Millimeter Large Diameter Diamond Drilling Technology By Means of Drilling Tool of Single Rotary and Double Tube in Zuantianshan Mine

在大口径金刚石单动双管钻探施工过程中,为了获取玄武岩更多的原状及圆形样品,采取在原孔位加大口径至Φ219 mm同心复钻。选用底喷式钻头,设计专用的隔水与返水变径接头,提高岩芯采取率;采用长钻具防斜保直钻进;采用特制的上下同心橡皮胶圈,导正小口径测斜仪防斜纠斜;采用与原孔岩芯同深度一起比对循证;保证新孔中心比原孔中心偏离不大。结果表明:重要岩矿段采芯率可达到95%,玄武岩层原状及圆形样品满足地质设计要求。其中两项新工艺可供类似工程参考借鉴。

This paper describes Φ219 millimeter large diameter diamond drilling technology by means of drilling tool of water insulation and single rotary and double tube in Zuantianshan mine. In order to get more original state and circular samples of basalt,take concentric drill in the original hole enlarging the diameter to Φ219 millimeter. The authors choose bottom spray type drill bit,design a special adaptor with functions of water-proof and water – return,improve the core recovery,keep the vertical drilling through the use of long drill tool. Using special concentric rubber aprons up and down,control and correction measures of deviation with the centralizer inclinometer,compared with the original hole and the depth of the core,the new hole center deviation compared with the original hole center is small. The results show that boring-core recovery of drilling hole is as high as 95% in important rock seam. The quality of samples of basalt with original state and circular conforms to the geological design requirements. Two new technologies can provide a reference for the similar project