"液量稳定"控压钻井方法

"Liquid Volume Stable" Managed Pressure Drilling Method

张桂林

Zhang Guilin

中石化胜利石油工程有限公司技术装备处, 山东东营 257001

Department of Technology & Equipment, Sinopec Shengli Oilfield Service Corporation, Dongying, Shandong, 257001, China

为了满足"窄密度窗口"地层安全钻井的需要,开展了"液量稳定"控压钻井技术研究。在分析井内压力关系的基础上,指出了当前控压钻井技术存在的问题与不足,提出了"液量稳定"控压钻井方法。该方法以地层压力与井底压力平衡为依据,在钻进中控制循环液量稳定,接单根时关井保持井内液量稳定,起下钻时关井并通过挤注与放出液体方式保证井内液量稳定,达到井内压力平衡要求。通过控制"液量稳定"来达到井底压力与地层压力平衡,是实现平衡压力钻井的一种有效方法。该方法在高压、超饱和、窄密度窗口盐水层钻井中获得成功,并形成了特色钻井技术。提出了实施要点与相关计算方法,为控压钻井技术的研究与应用提供了一种新思路。

In order to satisfy the safety drilling requirements in "narrow density window" formation,"liquid volume stable" managed pressure drilling was investigated.Based on the analysis of wellbore pressure,problems and deficiencies of managed pressure drilling were determined,and "liquid volume stable" managed pressure drilling method was proposed.Based on the balance between formation pressure and downhole pressure,the method involves keeping stable circulation fluid volume during drilling,and pipe connection under shut-in,shut-in during trip and keeping fluid in wellbore stable by squeezing in and releasing liquid,so as to keep pressure in wellbore balanced.By controlling the "liquid volume stable" to achieve balance between bottomhole pressure and formation pressure,is an effective way to achieve balanced pressure drilling.The technique had been successfully used in high pressure,ultra saturated,narrow density window brine formation drilling,forming a special drilling technology.Key points and related calculation method had been put forward,providing a new approach for research and application of managed pressure drilling.

https://doi.org/10.3969/j.issn.1001-0890.2013.04.012