松散砂岩取心技术的应用

Application of Coring Technology in the Loose Sandstone

砂岩取心是迄今为止仍然没有完全解决的钻探技术难题。砂岩的种类很多,但都有共同的特点:结构比较松散,无胶结或少量胶结,遇水膨胀,透水性好。在砂岩中钻探取心,岩心采取率不高,钻孔容易垮塌。为了解决砂岩取心钻探中的技术难题,从钻进工艺技术参数、取心器结构、钻头优化设计、冲洗液配方、钻机配套、岩心烧结卡取以及水压出心等多方面开展研究,总结出了一套砂岩取心技术,应用在实际钻探生产中,取得的各项技术指标完全满足地质要求,为地浸砂岩取心钻探提供了宝贵的经验。

Sandstone coring is a drilling technical problem that has not been completely solved so far. There are many kinds of sandstone, but they all have the same characteristics： loose structure, no cementation or slight cementation, expansion in water and good permeability. Core recovery is low in sandstone drilling and the borehole is easy to collapse. In order to solve the technical problems in sandstone coring drilling, a set of sandstone coring technologies has been summarized by the study on drilling process technical parameters, coring device structure, drill hit optimization design, mud formula, drilling machine matching, core getting by core sintering with drill and core collecting by water pressure, and has been applied in the actual drilling production. All the technical indexes met the geological requirements, which provide valuable experience for core drilling in in situ leaching sandstone.