【作者】 张永光；

【导师】 殷琨；

【作者基本信息】 吉林大学 ， 地质工程， 2011， 博士

【摘要】 冲击挤密潜孔锤钻进技术集冲击钻进、振动钻进、空气钻进及无排渣方法的优点于一体,钻进效率高,成孔质量好,是一种高效环保的浅层地热孔钻进技术。钻头结构形式,冲击挤密潜孔锤外管形状设计,尾部机构优化都直接影响钻进效率,是完善和推广该项技术的关键所在。本文以LS-DYNA显式动力分析为基础,对比了优化九阶梯钻头和凸轮旋压钻头在相同冲击荷载作用,相同计算时间,相同地层条件下的钻进深度,为凸轮旋压钻头挤土机理提供了理论依据,并在此基础上对凸轮旋压钻头做了机构改进,在原结构基本不变的条件下设计了螺旋球齿型和反S型切削刃凸轮旋压钻头,提高了钻进效率。对冲击挤密潜孔锤外管机构做了全新的结构设计,首先借鉴振动沉管桩增加管靴易入土工程实例,利用ANSYS/LS-DYNA显式动力分析有限元软件模拟分析了冲击挤密潜孔锤一段粗径外管粗径段出刃量锥角,长径比,两段粗径外管粗径段出刃量锥角,长径比,粗径位置,三段粗径外管的粗径段出刃量锥角,长径比,粗径段数目及位置等参数对钻进效率的影响,设计加工了多组活套式粗径外管,并进行了对比性室外冲击试验,对比分析确定了各情形下粗径外管的最优参数,验证了数值模拟的合理性和可靠性,为生产试验提供可靠的理论依据。在冲击挤密潜孔锤头部机构改进,中部机构重新设计的基础上,对其尾部机构的后轴套及花键轴做了优化设计,设计了花键轴底端凸肩装置,实现了两个零件轴向锁紧定位,解决了原冲击挤密潜孔锤工作不连续,效率低下的问题,并将表面仿生设计理论引入冲击挤密潜孔锤外部机构表面设计中,得到头部仿生非光滑表面设计宜采用凹坑表面仿生形态,中部和尾部仿生非光滑表面设计宜采用凹槽表面仿生形态,优化组合了一套完整的高效环保浅层地热孔冲击挤密潜孔锤钻进技术。更多还原

【Abstract】 Sallow geothermal energy is green and renewable sources of energy. It doesn’t only have a wide distribution and a large reserve, but also is clean, environmentally-friendly and reproducible. Further, its exploring doesn’t be affected by using areas and the seasons. Vigorously developing and exploiting sallow geothermal energy has major significance for satisfying the energy need of all the world, improving energy structure, alleviating environmental pollution, fulfilling the target on energy conservation and reduction of pollutant emissions of all countries and promoting the sustainable development of eco.At the same time, developing an effect environmental drilling method, just applying to geothermal hole, is very important. Then, the drilling technology of percussion-compact DTH hammer solves this drilling problem, and builds a strong foundation for exploiting and widely using sallow geothermal energy. Additionally, the drilling technology of percussion-compact DTH hammer also has a wide field of application with good prospects on geotechnical anchor engineering, no open-digging laying pipeline engineering and pile foundation engineering.Percussion-compact DTH hammer is an effect environmental drilling technology, and design on exterior structure of percussion-compact DTH hammer is the key. The exterior structure of percussion-compact DTH hammer contacts with soil around during the process of percussion-compact-rotary drilling. Therefore, the optimum design on exterior structure will improve drilling effect of percussion-compact DTH hammer.This paper just based on "Research on applying of an effect environmental drilling technology in exploring of sallow geothermal energy". After analysis on the effect environmental drilling technology of soft formation, mechanical model and finite element model of soft formation and exterior structure of DTH hammer were built and analyzed on numerical simulation. The forming reasons of "pile effect" were analyzed through dynamic simulation methods. Cam spinning bit, outer and tail structures were optimum designed, and the theory of surface non-smooth was applied to outer structure design. Based on experimental data, the parameters of exterior structure of the CJ-130 percussion-compact DTH hammer were defined. All these played an important part in exploiting the sallow geothermal energy. The main research contents and conclusions contain:1. Based on the theory of damage of soil body, combining the dynamic character of soil under live-loading, the forming reason of "pile effect" was analyzed from mechanism, and the numerical simulation of the "pile effect" was done, during which its forming process was observed. The continuous dynamic simulation of optimized nine multiple diameter drill pressing soil was analyzed, and then, the same analysis on Cam spinning bit was completed. The difference of pressing soil mechanism between these two drills was compared. Next, comparative trials were completed among circular cone bit, multiple diameter drill and cam spinning bit. The results showed that cam spinning bit had the top drilling effect, multiple diameter drill takes second place, and circular cone bit was the last. The reason of the cam spinning bit with high effect was conclude combining simulation and experiment. Given this, some improvements of cam spinning bit were done. I designed five cam spinning bits, including buttons well-distributed front cam spinning bit, buttons spiral-distributed front, unilateral channelized, double sided channelized and spiral-distributed channelized.2. Based on the result that outer tube effects on drilling efficiency is three times than that of drill, the outer tube structures, such as different angels of oblique edge, different slenderness ratios, different numbers and places of wide diameter, effects on drilling depth were calculated by use of ANSYS/LS-DYNA. The results deduced the best parameters. That is, the angel of oblique edge was 20°, the slenderness ratio of one wide diameter was 1.54, the slenderness ratio of two wide diameters(front-middle) is 1.42, the slenderness ratio of two wide diameters(front-back) is 1.35, and the slenderness ratio of three wide diameters is 1.15. All these drilling efficiency were higher than that of the same diameter outer tube.3. On the base of theory researches and numerical simulations, looping type test pieces of outer tubes were manufactured, and test-bed was built. Many compared experiments were made, including the angel of oblique edge, the slenderness ratio and the numbers and places of outer tube with one wide diameter, outer tube with two front-middle wide diameters, outer tube with two front-back wide diameters and three wide diameters. The end results deduced the best angel of oblique edge was 20°, the range of wide diameter was 2～4mm, the range of the slenderness ratio was 1.4～1.6. And the reasonable number of wide diameter is 1～2. The three wide diameters will be not consided.4. Test piece of outer tube withΦ34mm was secondary manufactued. Together with looping and matrix, it was made new sample of two or three sections joined. And the second compared experiments were made. As is shown from the results, the synergic parameters of exterior structure of the CJ-130 percussion-compact DTH hammer provided reliable test data for the following research. That is, the angel of oblique edge was 20°, the diameter of wide section isΦ134mm,the length is 201mm,the number of wide section is one and it situated at the bottom.5. Optimum designs on rear axle housing, castellated shaft and air Distributor of tail structure of percussion-compact DTH hammer were researched. As a result, the function of axial alignment self-locking came true in the tail structure. And it solved the discontinuous-"working on and off" problem of percussion-compact DTH hammer. In other words, continuous and effect drilling was carried out. At the same time, the simulate theory of surface non-smooth was applied to the surface design of outer structure. Then, experiment on exterior structure with non-smooth simulation surface was made. The results showed that drill with simulation surface of steel pit, and outer tube and tail structure with simulation surface of notch would help to improve drilling efficiency.The main innovation points in this paper contain:1. The forming process of "pile effect" was dynamic simulation analyzed by the non-linear finite element solver ANSYS/LS-DYNA, whose calculation is explicit, aided with implied. The drilling process of nine multiple diameter drill, cam spinning bit and the wide diameter outer tube were simulated by the same means.2. Optimum design on exterior structure of percussion-compact DTH hammer was done, borrowing ideas from pipe boots structure. The parameters of wide diameter outer tube were determined from numerical simulation and experimental research. And the drilling efficiency was improved.3. Flank spline, transferring from circumference direction, was applying to the tail structure of percussion-compact DTH hammer. So it solved the discontinuous problem of percussion-compact DTH hammer. The simulate theory of surface non-smooth was applied to the surface design of outer structure. The simulation surface helped to improve drilling efficiency of percussion-compact DTH hammer.更多还原