高应力扰动破岩机理及工具研究

发布时间：2018-09-11 08:21

【摘要】：破岩技术是油气钻井技术的核心内容,随着油气田开发日益深入,高效破岩技术更是提高破岩效率、减少钻进时间和安全、快速地降低钻井成本的重要因素之一；破岩效率的好坏直接决定着钻井速度和成本,更决定着钻井工程的经济效益。把高应力扰动破岩方法首次引入钻井工程,为提高钻井破岩效率提供了一个大胆的尝试及思路。本文通过对高应力扰动破岩和岩爆等机理等基础进行了调研,分析和总结。深部地层岩石内部积聚了很大的弹性应变能,缝端应力集中,没有超过强度值。由于深部地层的岩石中高应力一直存在。另外,岩石内部存在许多裂隙,属于非连续介质。若给岩石一个扰动力,使岩石内部常中止于此的裂纹扩展,随着岩石的裂纹发展,岩石刚度会突然劣化,直至完全破坏,甚至产生局部岩爆。论文开展了高应力扰动破岩工具方案设计。从高应力扰动耦合破岩,深部地层岩爆机理的特点出发,分析了高应力扰动破岩工具的功能及结构,并提出了具体的结构方案,论述了其工作原理。进一步,分析了动静载荷下岩石破岩能量变化,总结了高应力扰动破岩工具的详细设计思路。本文并不针对工程应用进行样机设计,而是开展原理性样机验证。工具的扰动力是通过控制阀的有效流通面积周期性变化,产生水击,使工具内活塞两端形成压差,跟钻柱自重形成合力,实现动静加载,扰动深部岩石,甚至发生岩爆,从而提高破岩效率。而阀的控制是由涡轮驱动的,进而需要分析阀水力转矩的大小规律和驱动阀,涡轮需要满足的功率大小,最后根据功率需要,进行涡轮设计。因此,后面以试验样机为例,着重从高应力扰动破岩工具关键设计的理论方面进行分析。在室内试验方面,设计了原理性样机,建立了试验台,开展了验证性试验,并对试验结果进行了分析,最后得出结论,该样机原理正确,能够实现动静组合加载,利用深部地层应力特点并通过辅助工具可以提高钻井破岩效率。本论文开展的研究工作,立足于前沿科学,运用理论分析和实验验证的方法,对高应力扰动破岩工具进行了原理性分析和样机试制,具有较高的理论和应用价值。不仅为钻井工程引入高应力破岩方法提供了宝贵经验、推动了钻井工程的技术进步,而且为国内的高效破岩技术提供了一个大胆的尝试、新方法和新思路。
[Abstract]:Rock breaking technology is the core content of oil and gas drilling technology. With the deepening development of oil and gas field, high efficiency rock breaking technology is one of the important factors to improve rock breaking efficiency, reduce drilling time and safety, and quickly reduce drilling cost. Rock breaking efficiency directly determines drilling speed and cost, but also determines the economic benefits of drilling engineering. The method of high stress disturbance rock breaking is introduced into drilling engineering for the first time, which provides a bold attempt and train of thought for improving drilling rock breaking efficiency. In this paper, the mechanism of high stress disturbance rock breaking and rock burst is investigated, analyzed and summarized. There is a great amount of elastic strain energy accumulated in the deep strata and the stress concentration at the fracture end is not more than the strength value. High stress has always existed in the rocks of deep strata. In addition, there are many cracks in the rock, which belong to discontinuous medium. If a disturbing force is given to the rock, the crack propagation in the rock usually stops here. With the development of the crack in the rock, the stiffness of the rock will suddenly deteriorate until it is completely destroyed, and even a local rock burst will occur. The scheme design of high stress disturbance rock breaking tool is carried out in this paper. Based on the characteristics of high stress disturbance coupled rock breaking and deep strata rock burst mechanism, the function and structure of high stress disturbance rock breaking tools are analyzed, and the concrete structure scheme is put forward and its working principle is discussed. Furthermore, the variation of rock breaking energy under dynamic and static loads is analyzed, and the detailed design ideas of high stress disturbance rock breaking tools are summarized. This paper does not carry on the prototype design for the engineering application, but carries out the principle prototype verification. The disturbing force of the tool is to produce water hammer through the periodic change of the effective circulation area of the control valve, so that the pressure difference between the two ends of the piston in the tool is formed, and the joint force is formed with the self-weight of the drill string, so as to realize the dynamic and dynamic loading, disturb the deep rock, or even rock burst. So as to improve the efficiency of rock breaking. The control of the valve is driven by the turbine, and it is necessary to analyze the law of the hydraulic torque of the valve and the driving valve, the power that the turbine needs to meet. Finally, the turbine design is carried out according to the power requirement. Therefore, the experimental prototype is taken as an example to analyze the key design theory of high stress disturbance rock breaking tool. In the aspect of indoor test, the principle prototype is designed, the test bench is set up, the verification test is carried out, and the test results are analyzed. Finally, it is concluded that the principle of the prototype is correct and the dynamic and static loading can be realized. The drilling rock breaking efficiency can be improved by using the characteristics of deep formation stress and auxiliary tools. The research work carried out in this paper is based on the frontier science. The theoretical analysis and experimental verification method are used to analyze the principle of high stress disturbance rock breaking tools and the prototype is trial-produced, which is of high theoretical and practical value. It not only provides valuable experience for drilling engineering to introduce high-stress rock breaking method, but also promotes the technical progress of drilling engineering, and provides a bold attempt, new method and new idea for domestic high-efficiency rock breaking technology.
【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】：TE21

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