摘要
随着我国油气勘探开发向地球深部进军,由深井超深井环空间隙小及大段盐膏层的存在带来的塑性地层卡钻、钻井液安全密度窗口窄等钻井工程难题对井身结构设计、钻井施工和固井质量提升带来了严峻挑战。为此,在分析国产扩眼器结构和功能局限性的基础上,通过结构设计、安全性模拟、流场分析及室内实验,研发了一种投球激活液压式可控随钻扩眼器并开展了现场试验。研究结果表明:①工具在极限钻压、极限扭矩、极限提拉工况下的安全系数分别为2.42、1.70、1.23,安全性能满足现场需求;②工具通过调节钻井液排量来控制刀翼推力,可以满足不同地层的扩眼需求;③工具在小排量时压耗变化更为明显,可通过投球后小排量憋压以判断工具在井下的工作状态;④室内及现场试验表明,工具投球后能够稳定执行刀翼展开和收回动作,试验井段目标扩眼井径241.30 mm,实际平均扩眼井径241.49 mm,相比扩眼前井径平均扩大14.53 mm,扩大率6.4%,与预定目标吻合。结论认为,可控随钻扩眼器有效缓解了地层缩颈导致的电测遇阻、挂卡等问题,为解决盐膏层缩颈、非常规套管作业提供了重要技术手段。
As oil and gas exploration and development in China steps into the deep strata,the small annulus clearance in deep and ultra deep wells and the presence of massive salt gypsum cause drilling engineering difficulties such as pipe sticking in plastic strata and narrow safety window of drilling fluid density,which poses severe challenges to casing program,drilling construction and cementing quality.In order to solve these problems,this paper analyzes the structural and functional limitations of domestic reamers,and then develops a ball-activation hydraulic controllable reamer while drilling by means of structural design,safety simulation,flow field analysis,and laboratory experiments.In addition,it is tested on site.And the following research results are obtained.First,the tool can meet the on-site safety requirements,with safety coefficients of 2.42,1.70,and 1.23 under extreme drilling pressure,extreme torque,and extreme pulling conditions,respectively.Second,the tool can control the thrust of the blade by regulating the flow rate of drilling fluid,so as to meet the needs of different reaming holes.Third,the pressure loss changes more significantly at a small flow rate,so the working state of the tool in the downhole can be determined by holding the pressure at a small flow rate after throwing the ball.Fourth,laboratory and field experimental results indicate that the tool can stably perform blade deployment and retraction actions after throwing the ball.The expected reaming hole diameter of the experimental well sec tion is 241.3 mm,and the actual average reaming hole diameter is 241.49 mm,which has an average enlargement of 14.53 mm compared with the hole diameter before reaming,with an expansion rate of 6.4%.Obviously,it is basically consistent with the preset target.In conclusion,the controllable reamer while drilling effectively alleviates the problems of electrical logging resistance and sticking caused by hole shrinkage,and provides a method for solving hole shrinkage in salt gypsum layers and unconventional casing operations.
作者
李玮
盖京明
李思琪
陈新勇
李钧儒
邹林浩
LI Wei;GAI Jingming;LI Siqi;CHEN Xinyong;LI Junru;ZOU Linhao(College of Petroleum Engineering,Northeast Petroleum University,Daqing,Heilongjiang 163318,China;National Engineering Research Center of Oil&Gas Drilling and Completion Technology,Beijing 102206,China;Engineering Technology Research Institute,CNPC Bohai Drilling Engineering Co.,Ltd.,Tianjin 300450,China)
出处
《天然气工业》
EI
CAS
CSCD
北大核心
2023年第12期84-90,共7页
Natural Gas Industry
基金
国家自然科学基金面上项目“万米深井PDC钻头冲击破岩机理及提速方法研究”(编号:52274005)。
关键词
超压油气藏
盐膏层
井眼缩颈
随钻扩眼器
非常规套管
Overpressure oil and gas reservoirs
Salt gypsum layer
Boreho le shrinkage
Reamer while drilling
Unconventional casing
