自张式膨胀管技术的研究与应用

Research and application of expansion casing technology for drilling holes in complex formations

摘要:

孔内膨胀管钻探技术是保障复杂地层孔壁稳定的有效技术之一。本文针对易出现缩径、坍塌、掉块的强水敏性地层，提出了一种自张式膨胀管护壁方法，并根据该方法的护壁原理研制了相适配的新型扩孔钻具、膨胀管及膨胀管投送装置，在不改变钻孔结构的情况下，对复杂孔段进行局部扩孔，投送膨胀管借助自身张力自然弹开而固定在相应的扩孔段，实现钻进时护壁。通过室内及现场试验对机具进行了优化，最终取得了良好的应用效果。试验证明：该方法操作简单可靠、易于定位，相较于水泥浆护壁具有处理速度快、停待时间短、减少重复处理等优势，适用于岩心钻探领域多孔段复杂地层的固壁与护壁，有利于降低孔内事故处理的成本、提高钻进效率，具有较好的推广应用价值。

Abstract:

Borehole expandable tubular drilling technology is one of the effective techniques to ensure the stability of borehole wall in complex formation. In this paper， a self-tensioning expandable tubular wall protection method is proposed for the strong water-sensitive strata prone to shrinkage， collapse and falling block. According to the wall protection principle of the method， a new type of reaming drill tool， expandable tubular and expandable tubular delivery device are developed to adapt to this method. Local reaming can be carried out on complex hole sections without changing the drilling structure. The delivery expansion tube naturally springs open with its own tension and is fixed in the corresponding reaming section to realize wall protection during drilling. The machine was optimized through indoor and field tests， and finally achieved good application results. The tests proved that： The method is simple， reliable and easy to locate. Compared with cement slurry wall protection， it has the advantages of fast processing speed， short stop time and less repeated processing. It is suitable for the solid wall and wall protection of complex formation in porous section in core drilling field， which is conducive to reducing the cost of in-hole accident treatment and improving drilling efficiency， and has good application value.