临兴区块钻井液仿生润滑剂研究和应用

Research and application of bionic lubricant for drilling fluid in Linxing Block

随着临兴区块钻井数量和难度逐渐增加,钻井过程中出现了摩阻高、易卡钻、钻速慢、周期长等问题,对钻井液润滑性提出了更高的要求。为了提高钻井液润滑性,结合临兴区块地质特征,针对高摩阻、钻速慢、周期长的问题,运用试验的方法,通过长链脂肪酸和多元醇,在约150℃反应6 h,研制了仿生润滑剂,经过性能评价,润滑剂的极压润滑系数降低率达到90%,抗温可达120℃,可以显著提高滤饼的润滑性能。同时,润滑剂对钻井液体系的流变性能影响较小。现场应用结果表明可以提高机械钻速33%,降低井眼扩大率34%,水平井作业井深超过3500 m,可以为后续井作业提供借鉴和参考。

With the increasing number and difficulty of drilling in Linxing Block,problems such as high friction,easy sticking,slow ROP and long drilling cycle appear in the drilling process,which put forward higher requirements for the lubricity of drilling fluid.In order to improve the lubricity of drilling fluid,combined with the geological characteristics of Linxing Block,aiming at the problems of high friction,slow ROP and long cycle,the bionic lubricant was developed by using the test method,through the reaction of long chain fatty acids and polyols at about 150℃for 6 h.After performance evaluation,the extreme pressure lubrication coefficient of the lubricant was reduced by 90%,and the temperature resistance was up to 120℃,It can significantly improve the lubricity of the filter cake.At the same time,the lubricant has little effect on the rheological properties of drilling fluid system.The field application results show that the ROP can be increased by 33%and the hole enlargement rate can be reduced by 34%,the depth of horizontal well is more than 3500 m,which can provide reference for subsequent well operations.