小井眼随钻扩眼技术研究

发布时间：2018-04-27 01:40

本文选题：小井眼 + 扩眼器　；参考：《西南石油大学》2015年硕士论文

【摘要】：小井眼侧钻主要解决油田老区块上具有开发价值的加深井、变形井和事故井恢复产能的难题,是目前各油田降低成本增产原油的重要措施之一,随钻扩眼技术是小井眼侧钻的关键技术之一,主要解决因地层蠕变或者地层不稳定导致的缩径或井壁坍塌等问题,并且能十分有效的解决小井眼固井质量差的问题。由于扩眼过程中形成的井眼为阶梯形井眼,跟常规井的井壁受力有很大区别,因此,应根据其自身的工作特点与要求设计出能有效吃入井壁且高效、稳定切削岩石的扩眼刀翼。本文在立足对国内外扩眼刀翼结构调查与认知的基础上,借鉴PDC钻头的设计方法,开展随钻扩眼刀翼结构与布齿设计,通过有限元分析软件分析了刀翼流道的流场情况,并且开展“考虑多环境载荷”下的井壁岩石破碎模拟,获取上覆岩层压力、水平地应力和井眼压力作用下的钻齿破碎井壁岩石的互作用特性,并根据获得结果调整、优化扩眼器刀翼的布齿参数。本文主要完成的研究工作有以下几个方面：(1)调研国内外扩眼器的现状,了解了扩眼器的发展历程和现阶段国内外公司具有代表性的扩眼器结构和工作原理,为后文的设计提供指导。(2)吸取了现有较为先进的扩眼器的设计理念,针对3000m左右井段小井眼侧钻后全面钻进阶段裸眼段的扩径需求,设计了一种具有硬支撑效果,功能先进,扩径率大且稳定的随钻扩眼器。(3)借鉴PDC钻头的设计原理,对扩眼刀翼进行了结构设计和布齿设计。并且针对扩眼刀翼容易产生泥包的情况,做了改进设计,方法是“宽流域,减深度”。利用ANSYS软件做了流场分析,并且研究了钻井液排量、粘度、密度、喷口倾角等对切削刃上齿面流速的影响。(4)开展了单齿破碎阶梯形井壁岩石的模拟。优化了刀翼的布齿参数。本文开展的工作将有助于加强对扩眼器破碎环形井壁机理的认识,并对扩眼器及其刀翼的设计和随钻扩眼工艺的实施提供一定的指导作用。
[Abstract]:Small hole sidetracking is one of the most important measures to reduce the cost and increase production of crude oil in oil fields, mainly to solve the problem of recovery productivity of deep wells, deformed wells and accident wells with development value in old blocks of oil fields. The technology of reaming while drilling is one of the key techniques of sidetracking, which mainly solves the problems of shrinkage or wall collapse caused by formation creep or formation instability, and can effectively solve the problem of poor cementing quality of small borehole. Due to the fact that the borehole formed in the process of reaming is a step shaped well, which is very different from that of the conventional well, the reaming blade which can effectively eat into the well wall and be efficient and stable in cutting rock should be designed according to its own working characteristics and requirements. Based on the investigation and cognition of the reaming blade structure at home and abroad and the design method of PDC bit, the structure and tooth distribution design of the reaming blade while drilling is carried out. The flow field of the blade runner is analyzed by finite element analysis software. Under the condition of "considering multiple environmental loads", the rock fragmentation simulation of borehole lining is carried out to obtain the interaction characteristics of drilling and breaking rock under the action of overburden rock pressure, horizontal ground stress and borehole pressure, and adjusted according to the obtained results. To optimize the tooth distribution parameters of the reamer blade. The main research work accomplished in this paper is as follows: 1) to investigate the present situation of reamer at home and abroad, to understand the development of reamer and the typical structure and working principle of reamer in domestic and foreign companies at present. In order to provide guidance for the later design, this paper absorbs the design idea of the more advanced reaming device, aiming at the needs of expanding the diameter of the open-hole section in the comprehensive drilling stage after the small hole side drilling of about 3000 m, designs a new type with hard support effect and advanced function. Based on the design principle of PDC bit, the structure design and tooth arrangement design of reaming cutter blade are carried out. Aiming at the situation that the reaming blade is easy to produce mud bag, the improved design is made, the method is "wide basin, reduce depth". The influence of drilling fluid displacement, viscosity, density and nozzle inclination on the flow velocity on the cutting edge has been studied by using ANSYS software. The simulation of single tooth broken step sidewall rock has been carried out. The tooth distribution parameters of the blade are optimized. The work carried out in this paper will help to strengthen the understanding of the mechanism of hole reamer breaking annular wellbore and provide some guidance for the design of reamer and its blade as well as the implementation of reaming while drilling process.
【学位授予单位】：西南石油大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TE921.1

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