液动冲击旋转钻井技术在玉门青西油田的应用

APPLICATION OF HYDRAULICALLY IMPACT-ING-ROTARY DRILLING TECHNIQUE IN QINGXI AREA OF YUMEN OIL FIELD

玉门油田青西地区上部志留系、白垩系推覆体老地层的机械钻速一直影响着青西地区钻井速度的提高。从破岩理论上讲 ,冲击旋转钻井技术是解决硬地层钻进难题最有效的方法之一。利用液动冲击器进行旋转钻井是常规旋转钻井技术上发展起来的一种钻井新方法 ,它可以大幅度提高钻进效率、降低钻井成本、延长钻头的使用寿命。该技术应用在岩石可钻性差的地层中 ,可明显提高机械钻速。文章介绍了玉门青西地区地层特点及地质分层、所使用的DGSC— 2 0 3冲击器工作原理和结构特点 ,以及在青西地区L114井的应用情况 ,得出的结论是DGSC— 2 0 3液力冲击器在L114井上部推覆体老地层的钻进井段的使用中 ,使机械钻速得以明显提高。但由于本井所使用的冲击器尺寸偏小 ,井斜未能得到较好控制。文章最后提出了进一步研究液动冲击器的建议 :在使用过程中出现泵压比设计值明显偏大现象 ,应研究进一步降低冲击器的工作压降 ,提高射流元件的使用寿命。液力冲击器的直径应由小到大并形成系列化产品 ,可全面解决石油钻井硬岩钻进难题等。

The penetration rate of the old strata of Upper Silurian and Cretaceous nappes at Qingxi area of Yumen oil field has always influence the drilling speed's being rasied at this area. Theoretically, the impactmg-rotary drilling technique is one of the most effective methods of drilling hard strata. The rotary drilling by use of hydraulic impactor is a new drilling method developed on the basis of conventional rotary drilling technique. It may greatly raise drilling efficiency, reduce drilling cost and lengthen the service life of bit. The penetration rate can be obviously raised by applying the technique to the strata with poor drillability. In the paper, through introducing the stratigraphic properties and geological layering at Qingxi area, the working principle and structural characters of the DGSC-203 impactor used and its application to well L144 at Qingxi area, it is concluded that the penetration rate was obviously raised in drilling the nappe old strata in well L114 by use of the DGSC-203 impactor. However, the hole deviation couldn't be well controlled because the used impactor size was on the small side. In the paper, it is suggested that the operating pressure of the impactor should be further reduced so as to enhance the service life of jet unit, because the pump pressure occurred in the course of operating was much greater than the designed one; and the difficult problem of drilling the hard strata for oil and gas may be overall solved through producing a series of hydraulic impactors with different diameter sizes.