Abstract:〗Deep ice core drilling is an important constituent part of the polar scientific research. In polar exploration sampling process, at the same time of achieving high quality samples, the drilling fluid pollution to the polar region should be reduced to the lowest degree, which has great significance to the polar native environment protection. According to the stratum conditions of the polar scientific drilling, a transport model of pollutant in the snow layer is established by Visual Modflow. When the pollutants concentration maintains constant, numerical simulation for the borehole pollutants is made to predict the pollutants in snow plume diffusion range in a decade. On this basis, contrastive analysis is made on the pollutant dispersion ability of snow under different dispersion coefficient. The drilling fluid used in the polar is 10 times that of water, with the increase of pollutants viscosity, the diffusion range will also be reduced correspondingly. This study result lays the important theoretical and technical basis for the evaluation of the influence of drilling fluid used in polar ice core drilling on the polar environment.

Abstract:Based on the bionic coupling theory and according to non-smooth morphology of shells, mole cricket and other animals & plants, a new kind of bionic PDC tooth is developed. The analysis is made on the single tooth motion process before and after the wear by abaqus finite element software and the comparative analysis is made with the stress distribution state of the common PDC teeth. It can be seen that under the same conditions, the non-smooth PDC cutting teeth have better stress value and distribution state than the common PDC ones with good rock breaking effect. In addition, the abrasion ratio test is also made on these 2 kinds of cutting teeth; the test results also prove that the PDC bionic PDC teeth have some superiority.

Abstract:For oil shale situ high-temperature mining, underground frozen wall should be constructed to prevent underground water flowing into the mining area and the leakage of oil and gas．The buffer zone between the high-temperature mining area and the freezing zone of underground frozen wall not only affects oil shale mining and frozen wall cooling effects but also affects the entire project construction and operating costs. By theoretical calculation method and numerical simulation, with the lowest cost as the goal, the detailed calculation and analysis are made and the rational buffer distance is determined, which could be the theoretical guidance to underground frozen wall design for oil shale in situ high-temperature mining.

Abstract:Cutting heat generated during rotary drilling is extremely easy to melt ice located in warm ice layer of deep ice cap because the high temperature is almost close to or even reach ice pressure melting point, which results in low penetration rate, poor core recovery and frequent sticking accidents. So it is necessary to design a device to test the cutting heat which is influenced by WOB, rotation speed and the structure of cutting tool; the test results would provide the theoretical basis for the design of cutting tool structure and optimization of drilling parameters. With the XY-1 core drilling system as the platform, using the wireless signal transmission principle, the test stand for testing cutting heat generated during rotational drilling in ice layer is designed. Preliminary test results show that by this experimental device, the parameters of WOB, torque and cutting temperature can be accurately measured, which can also be used for the related experimental study.

Abstract:大扭矩反扭装置是研制铠装电缆冰下基岩电动机械取心钻具的主要部分之一，该装置的失效将导致钻进无法进行，甚至将造成钻具脱落等严重的孔内事故。设计了铠装电缆钻具反扭装置实验台，并就实验装置的设计思想、设计原则、主要结构参数及初步实验结果进行了详细介绍。该实验台可以测试反扭装置在不同温度冰层和不同孔径任意组合下所能提供的反扭矩大小以及产生的下滑阻力。初步实验验证，该实验台工作性能良好，可以为更好的选择反扭装置类型及最优的使用参数提供重要依据。

Abstract:In the field of drilling technology in the polar regions，the coring tools of armored cable type electric machinery are widely used. Optimizing and designing the anti-torque system to improve the anti-torsion is the key for the successful core drilling in sub-glacial bedrock with electric machinery coring tool. In order to analyze all the performance of anti-torque device，the simulation method based on digital virtual prototype RecurDyn is proposed. Anti-torque device is composed of planar six-bar mechanism; the inventor software is introduced into RecurDyn to establish the geometry model of anti-torque device, by which the motion simulation and analysis are carried out. The paper introduces the method and procedures of how to use the RecurDyn software to realize the motion simulation and the analysis on the planar six-bar mechanism (anti-torque device). With anti-torque device as the research object, the motion of anti-torque device is showed by animation in RecurDyn/post module and the chart is used to reflect the result of motion simulation, by which the science, the rationality and the practicability of anti-torque device design are proved and the predetermined position changing can be determined to satisfy the request of balance drilling in polar regions.

Abstract:Mud refrigeration system is very important in the drilling process of gas hydrate sampling. This article describes the structure and working principle of the gas hydrate mud refrigeration system developed by Jilin University. The field application tests were made in Qiangtang basin, Muli basin and Mohe basin, the test results show that the application scope of this refrigeration system is wide with stable and reliable performance, and can be used in gas hydrate drilling in high altitude and high latitude permafrost regions and some other special areas.

Abstract:Aluminum drill pipe has the advantages of low density, high specific strength and strong corrosion resistance, but the wear resistance is low. In the practical application, the aluminum drill pipe body and steel tool joints are assembled together to form a drill string, the steel tool joints are used to withstand the screwing and unloading operation. Because of the differences of aluminum and steel in the elastic modulus, thermal expansion coefficient and the yield strength, the unreliable connections often happen. The theoretical calculations of interference are made on aluminum drill pipe with internal upset, which has the diameter of 147mm and wall thickness of 13mm, the interference range should be 0.712～1.009mm to meet transfer load without plastic deformation. The paper also introduces the assembly process of drill rod and steel joint.

Abstract:Spindle-type core drill is the most popular drill in geological core drilling engineering. This article presents the improvement of the vertical spindle speed detecting method for spindle-type core drill and introduces the development of speed detecting system based on the key technologies of the sensor, counter module and acquisition machine. The counter module design is optimized to improve the accuracy of the speed measurement. The system has been examined by the NGH drilling program in Mohe, which can surely meet the requirement.

Abstract:Based on the complicated geological conditions in Cretaceous strata scientific drilling in Jiao-Lai basin, the paper introduces the construction about the borehole structure, BHA, flushing fluid selection and drilling technical parameters. According to the difficult problems of hydration dispersion in mudstone strata, oversized diameter caused by borehole collapse and bit balling, the solutions for advanced open borehole drilling and the selection of low solid inhibited flushing fluid and drill bit are mainly discussed.

Abstract:For the problems of high gas emission and gas transfinite in upper corner and return air from 1303 working face of Guojiahe mine， by the analysis and calculation of the principles and parameters of gas drainage for high-position borehole and combined with the production conditions of working face, the gas drainage technologies for conventional high-position borehole and high-position borehole with large diameter were performed in practice. The practical results show that the latter is much better than the former and effectively solves the problems of the gas transfinite and improves the safe production conditions of the working face.

Abstract:Sawayaerdun gold deposit is located in the Midwest of Tarim plate across two secondary tectonic units in Dongelai gold-antimony polymetallic metallogenic belt, where the structure is developed with strong rock alteration. Because of high altitude, bad climate conditions and the steep mountain roads, water supply is very difficult for the construction. According to the difficulties of broken rocks, difficult coring, borehole deviation, poor water supply and bad climate conditions encountered in the construction, the specific technical measures are introduced.

Abstract:A drill sticking accident caused ZK001 borehole abandonment in Jiaozhuang iron ore area of Henan, the construction technology was improved by using proper equipment and high-quality mud, the final hole with depth of 1115.72m was reached with good technical indexes. Analysis is made on the borehole structure, drilling methods and properties of flushing fluid; the problems appeared in the construction and the countermeasures are briefly discussed.

Abstract:According to the geological engineering difficulties in AT9 well area and the special requirement of anti-bumping in the straight section of cluster wells, the designs of well location, platform layout, borehole trajectory and well structure are optimized. The paper introduces the key techniques of MWD anti-bumping, PDC straight spiral rod composite drilling and drilling fluid in drilling process, analyzes the technical rationality and the development economy of cluster well group and verifies the applicability of the cluster drilling technology in AT9 well area.

Abstract:5 kinds of diamond drilling bits were prepared with different matrix hardness and profiles by hot pressing sintering method, which were tested in engineering exploration and compared with the common electroplated diamond drilling bits to analyze the drilling efficiency. The result shows that by optimized design, the hot pressing sintering diamond bits are suitable for engineering exploration equally, their drilling efficiency are almost equal to or even higher than that of the electroplated diamond drilling bits. In weathered limestone formation drilling, the lower the matrix hardness of hot pressing sintering bit, the higher the drilling efficiency, and vice versa. The profile of bit by special teeth design is faster exposed than that by plain teeth design with higher drilling efficiency.

Abstract:In order to meet the deep core drilling requirements and based on the analysis on the advantages and disadvantages of the existing similar mud pumps in the market, the main problems to be solved for new mud pump are put forward. NBB-390～52/11～8 variable displacement pump is introduced about its main components, characteristics, technical parameters and test running.

Abstract:Well track control is important in drilling deep well and directional well. The electromagnetic measurement while drilling system can monitor and transmit the state parameters of borehole to ground device by wireless electromagnetic wave. This system is applied widely for its high transmission rate and getting none influence from drilling fluid. The paper elaborates a self-developed electromagnetic measurement while drilling system in China and its test situation, which can receive signal up to 200mV from borehole of 609m in depth. The experimental research shows that this system is reliable and can satisfy the requirement of the annulus pressure, temperature and other parameters near the bit.

Abstract:Take φ2500mm comb bit as the object, use three-dimension drawing software Solidworks to establish the three-dimension modal of the bit, apply a new generation of multi-physics field collaborative simulation environment Ansys Workbench for mesh generation and static analysis, the equivalent stress and displacement nephogram of the overall structure were got and the maximum deformation value, maximum stress value and the location of the maximum stress point of the bit under the maximum load and wing plate force condition were obtained. The data obtained are very critical to check the strength and stiffness of the bit and important in the optimization of design process.

Abstract:For deep foundation pit construction, if in the condition of shallow buried underwater confined water, the tube well is applied to lower underground water level and different measures are taken for well sealing to ensure the underground water level to be controlled within the scope of the construction requirements. The paper introduces the dewatering construction for deep foundation pit in a project of Shandong and the relative well sealing plan as well as the construction process for the relief well with confined water head.

Abstract:The smallest diameter limit for bored grouting pile construction in Shanghai area is analyzed theoretically and discussed. By a construction case of a bore grouting pile with the diameter of 400 mm, the discussion is made on the measures of construction technologies and quality assurance for the bore grouting pile with the diameter less than 550 mm, and the possibility of the design and construction for bore grouting pile with even smaller diameter is also explored.

Abstract:Take an example of the foundation pit excavation for a renovation project in Zhengzhou, the paper describes the purpose and content of monitoring, monitoring accuracy and instrument selection, the layout of monitoring points and monitoring methods as well as monitoring alarm values and monitoring frequency. The practice shows that by timely capturing small changes in construction to realize information construction, the foundation pit and the surrounding environment are protected.

Abstract:Grouting pressure control is an important step in curtain grouting, by the analysis on the grouting pressure, the process of grouting filling, diffusion and compaction in rock fissures can be distinguished to regulate the slurry concentration, control the grouting volume, and further more to control the water control effects in curtain grouting and the grouting construction cost to a large extent. According to a curtain grouting water control project in Zhaojiawan copper mine, analysis is made on the variation of grouting pressure during the process of grouting filling, diffusion and compaction in rock fissures, which can be the reference to the pressure control of grouting construction.