大直径反井钻机关键技术研究

发布时间：2018-07-21 14:11

【摘要】：我国矿山、水电、交通等地下工程需要建设大量井筒,作为进出口、通风、安全逃逸通道等,许多井筒都有下部出口。以前这类工程采用的钻爆法正向施工,在安全和效率方面存在许多问题,没有充分利用大部分工程具有下部出口这一有利工程条件。因此,本文提出反井钻井法凿井新工艺,达到综合机械化破岩钻进,操作人员不下井作业,从根本解决凿井安全问题。反井钻机采用的是由上向下钻进导孔,然后由下向上扩孔的施工工艺,以前多用作爆破刷大的导井,作为反井钻井凿井法,需要一次扩孔到所需直径,钻进直径从1.4m到5m,破岩面积增大12.7倍,需要解决大体积机械破岩、大面积暴露井帮稳定及控制理论,以及相适应的大直径反井钻机。本文对反井钻井凿井新工艺的研究背景、研究目标及技术路线进行了分析,确定了大直径反井钻机技术关键。大体积破岩采用的盘形滚刀和镶齿滚刀,本文对两种滚刀破岩机理进行理论分析、实验室试验,并采用LS-DYNA动态有限元,对镶齿盘型滚刀破岩进行了数值分析,在岩石为花岗岩条件下,两种滚刀压入岩体的深度与正压力成正比,同样正压力条件下,镶齿滚刀压入深度大,且破碎单位体积岩石能耗相对小,为了达到同样破岩效果,盘形滚刀所需压力大,也增大了切向推力,这样也需要更大的扭矩和钻机功率,考虑反井钻机特点,本文认为镶齿滚刀更适合反井钻井法凿井大体积破岩。对于大直径反井钻机扩孔钻头结构进行分析,提出了力矩平衡钻头滚刀布置原则,形成了5m大直径扩孔钻头。在对滚刀及扩孔钻头受力分析基础上,研究确定了大直径反井钻机主要技术参数：导孔直径350-380mm、扩孔直径3.5-5.0m、拉力600kN、出轴转速0-5rpm、扭矩300kNm等,为大直径反井钻机设计打下基础。大直径反井井帮需要在扩孔钻进、设备拆除及支护期间长时间暴露,井帮稳定是反井钻井凿井法成败的技术关键,地层条件、地应力及地质构造是影响井帮稳定的主要因素,本文建立了井帮力学分析模型,采用剪切破坏强度理论,确定了井帮失稳条件,提出采用地层改性方法,通过对破碎地层的注浆加固,提高了软弱地层的完整性和等效模量,使地层中的塑性变形区域消失,软弱地层塌孔和缩颈的风险大大减小。通过计算对比,在煤矿岩石地层条件下注浆扩散直径在10m,能够达到反井井帮稳定。本文在分析大直径反井钻井穿过的不同地层条件的基础上,研究确定5种反井钻井凿井工艺,包括大直径反井一次成井、局部开挖预支护、定向钻进导孔、地表局部不稳定地层加固、局部破碎地层单孔加固、地面预注浆地层改性等,使反井钻井凿井法能够在不同工程条件和地质条件得到应用。本文对倒“T”新型大直径反井钻架结构在钻进、拆卸钻杆过程中,钻架受力及变形进行了模拟计算,对分体式大直径扩孔钻头及滚刀布置进行了分析,成功研制出5.0m大直径反井钻机。在此基础上,在煤矿井筒工程中进行工业性试验,通过工程实践检验了滚刀破岩及地层稳定理论,大直径反井钻机的设计和反井钻井工艺合理性,证明反井钻井凿井法的是一种可靠地凿井工艺。
[Abstract]:Underground projects such as mine, hydropower, transportation and other underground projects in our country need to build a large number of wellbore, as the import, export, ventilation, safe escape channel and so on. Many wellbore have lower exit. The drilling and blasting method used in this kind of project is forward to construction, and there are many problems in safety and efficiency. It is not good to make full use of most of the projects with the lower exit. Engineering conditions. Therefore, this paper puts forward a new drilling technique of anti well drilling method to achieve comprehensive mechanized rock breaking drilling, and the operators do not work well, so as to solve the problem of drilling safety fundamentally.
The anti well drilling rig adopts the construction process from the upper and down to the guide hole, and then the construction technology of the lower upward hole enlarging. Before the drilling well, it needs to expand the hole to the required diameter, the diameter from 1.4m to 5m, the rock breaking area is increased by 12.7 times, the large volume mechanical rock breaking and the large area exposure well are needed. In this paper, the research background of the new technology of anti well drilling, the research target and the technical route are analyzed in this paper, and the key of the large diameter anti well rig is determined.
The disc hob and hob hob used in large volume rock breaking are carried out in this paper. The rock breaking mechanism of two kinds of hob is analyzed theoretically, laboratory test and the dynamic finite element method of LS-DYNA are used to analyze the rock breaking rock of the insert type hob. Under the condition of granite, the depth of the rock mass is proportional to the positive pressure, and the same positive pressure is made. Under the force conditions, the insert hob has a large depth of pressure, and the energy consumption of the broken unit volume is relatively small. In order to achieve the same rock breaking effect, the disc hob needs large pressure and also increases the tangential thrust. This also requires greater torque and drill power, considering the characteristics of the drilling rig. This paper considers that the insert hob is more suitable for the drilling of the well drilling method. In the analysis of the structure of the reaming drill bit for the large diameter counter well drilling machine, the principle of the hob layout of the moment balance bit is put forward, and the 5m large diameter reaming bit is formed. On the basis of the force analysis of the hob and the reaming bit, the main technical parameters of the large diameter drill rig are determined: the diameter of the guide hole 350-380mm, the diameter of the reaming 3.5-5.0m, and the drawing of the hole diameter. The force 600kN, the shaft speed 0-5rpm, torque 300kNm and so on, lay the foundation for the design of large diameter anti drill rigs.
The large diameter reverse well drilling needs to expand drilling, remove the equipment and expose long time during the support period. The stability of the well is the key to the success or failure of the anti well drilling method. The formation conditions, ground stress and geological structure are the main factors that affect the stability of the well. In this paper, the well Gang mechanics analysis model is established and the shear failure strength theory is adopted. The formation modification method is adopted to improve the integrity and the equivalent modulus of the weak stratum by the grouting reinforcement of the fractured stratum, and the plastic deformation area in the stratum is disappearing, the risk of the collapse and necking of the weak stratum is greatly reduced. The grouting diffusion in the coal mine rock stratum is in 10m through calculation and comparison. It can achieve the stability of the well side of the well.
On the basis of analyzing the different formation conditions of large diameter reverse well drilling, this paper studies and determines 5 kinds of reverse well drilling technology, including large diameter reverse well first well formation, local excavation Presupport, directional drilling guide hole, local unstable ground reinforcement, local broken ground single hole reinforcement, ground pre grouting formation modification, etc. Drilling rig drilling method can be applied in different engineering conditions and geological conditions. In this paper, a new type of inverted "T" large diameter reverse well drilling frame structure in the process of drilling and removing drill rod is simulated, and the layout of the large diameter hole drilling bit and hob is analyzed, and the 5.0m large diameter anti well drill has been successfully developed. On this basis, the industrial test is carried out in the coal mine shaft engineering. Through the engineering practice, the theory of rock breaking and formation stability of the hob is tested, the design of the large diameter anti well drill and the rationality of the well drilling technology are proved. It is proved that the well drilling method is a reliable drilling technique.
【学位授予单位】：北京科技大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：TV554

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