Abstract:The cavity building by water jet is the important way of coal bed methane well completion. In order to optimize the nozzle for water jet tools to enlarge cavity diameter and improve cavity building efficiency, the similar coal samples were prepared, rock breaking effects were tested by continuous jet and cavitating jet in laboratory and the application was carried out in the field. The results showed that under the condition of free jet, the best rock breaking effects were at jet distance of 200mm and 300mm for continuous jet and cavitating jet respectively. Under the condition of submerged jet, the continuous jet could not erode the coal sample; the eroding diameter of cavitating jet increased first, then decreased tending to be stable; and when the submerged depth was 200mm, the eroding diameter reached the maximum. The eroding depth increased with the increase of submerged depth; by the submerged depth of 300mm, the eroding depth was tending to be stable and decreased slowly. This research provides the basis for nozzle selection and optical design of water jet tools.

Abstract:Because of fracture development in upper layer of Majing structure in Western Sichuan with low formation bearing capacity and dense well spacing, channeling with adjacent wells is easily occur in drilling process and lost circulation is often encountered, even leading to complex loss circulation. Although conventional bridge plug can be effectively used, the repeated leakage and flowing backward frequently occur for the poor formation bearing capacity with low onetime success rate. In order to improve plugging effect and onetime success rate, on the basis of the original plugging technology, efficient plugging agent was introduced, through the formula optimization in laborotory and construction process improvement, efficient bridge plug technology has been formed. The field test shows that the technology has high onetime success rate and good plugging effect, which provides a new method to solve the above mentioned complex lost circulation and has certain guiding significance for dealing with complex lost circulation.

Abstract:Drilling fluid properties and performance parameters have significant influence on Antarctic scientific drilling. Drilling fluids should have appropriate viscosity and density to cool drill bit, balance hole wall pressure, carry ice chips and clean hole bottom; in addition, its properties, such as electrical conductivity, thermal conductivity and corrosion, also have important influence on drilling tools for normal operation and downhole information transmission. According to the types of drilling fluid used in Antarctic, experimental tests were made on the conductivity, thermal conductivity and corrosion on sealing components of 6 kinds of medium DSO-3.0cst, KF96 silicone oil-2.0cst, ethyl butyrate, n-butyl butyrate, n-amyl butyrate and n-propyl propionate respectively under different temperatures, the drilling fluids and sealing materials suitable for Antarctic are selected, which can be important reference for drilling fluid selection and drilling tools design.

Abstract:针对常规漂珠的批量生产限制、承压能力差，非漂珠低密度水泥浆体系密度可控范围窄、低温强度低等问题，进行了新型深井高强低密度水泥浆体系的研究。选用新型高承压人造空心微珠作为主减轻剂，以颗粒的合理级配及紧密堆积为理论基础，通过水泥石抗压强度、水泥浆沉降稳定性等试验优选了 DC-1、DC-2外掺料，并确定最优配比。复配外加剂体系后，研制出密度为1.30～1.40 g/cm3的低密度水泥浆体系，具有密度低、强度高、稳定好等特点。该体系泥浆在大庆油According to the problems of conventional floating bead about mass production limit, poor resistance to pressure and non floating bead about narrow controllable range and low temperature strength, the study was made on high compressive strength and low density cement slurry system for new deep well. New high pressure artificial cenospheres were selected as density reducer, on the theoretical basis of reasonable gradation of particles and dense packing and by the cement compressing strength and cement slurry sedimentation stability tests, DC-1 and DC-2 additives were optimized and the optimal proportion was determined. With the additive system completion, new cement slurry system of 1.30～1.40g/cm3 was developed with the characteristics of low density, high compressive strength and good sedimentary stability, this slurry system was applied in Zhaoshen well 19 in Xujiaweizi block of Daqing oilfield. The good application effects show its good popularization and application prospect.田徐家围子区块肇深19井成功应用，取得较好的效果，具有良好的推广应用前景。

Abstract:Wall protection and plugging has been technical difficulty in deep hole drilling. In the drilling construction for deep prospecting projects in Xiaoqinling, because of the complex regional geology with tectonic development and fractured rocks, block falling, hole collapse and leakage often occurred in drilling process and mud plugging effect was poor, while good result was achieved by slurry plugging in the construction. According to the application of cement slurry plugging technology for deep drilling projects in Xiaoqinling, the paper analyzes and summarizes wall protection and plugging technology for deep core drilling, puts forward the requirements of deep holes grouting and plugging technology to the performance of quick-setting cement slurry and gives advices to the related drilling construction in this area.

Abstract:How to reduce drilling friction is the most difficult problem in horizontal drilling. Main tools for friction reducing are bearing sub, low-torque drill pipe, DSTR nipple joint, oscillating drag reduction device, only a few research on non-rotational drill pipe protector for friction reducing has been conducted. Comparing with non-rotational drill pipe protector, the other tools have some limitations, mainly in lower safety for too many subs or joints and key seats creating. Non-rotational drill pipe protector was used in the horizontal section drilling of Yaoqing 33-2HF, the friction between drilling tool and borehole was greatly reduced, so that drilling speed increased by 40.40% and the drilling cycle was shorten 57.79%, which provides reference for long horizontal well operation in the future.

Abstract:Industrialized horizontal wells is an emerging technical means for newly developed tight oil and gas development and unconventional oil and gas resource development, by optimizing the platform wells layout and line production to improve the construction efficiency of well drilling and completion as well as post operation, so as to shorten the construction period and reduce the cost. Based on the integrated application of the industrialized organization in target block, line production and drilling efficiency improving, the drilling cycle of the target block is greatly shortened and the production schedule are completed. By the analysis on the difficulties of industrialized drilling construction, the paper elaborates the key technologies for modular construction of industrialized drilling operations, which provides useful reference for the same type of wells construction.

Abstract:The new type brine recovery well AK1 is located at the old area of Beypazari trona solution mining zone. AK1 was completed by the SDC-1500 truck mounted rig which was independently developed by the Institute of Exploration Techniques, CAGS. Special casing string was set in the borehole. Innovative negative pressure pumping method is used in AK1 to get the recovery from underground. The recovery of AK1 is more than 3 times of that from the normal production well, which has alleviated the shortage of brine supply for processing factory and improved the production efficiency.

Abstract:Hot dry rock strata usually are of igneous rocks with strong abrasion and poor drillability. Because of the low drilling efficiency of conventional drilling methods, SC-86H high energy liquid-jet hammer was specially developed for hot dry rock strata drilling, and the ground drilling tests were carried out on the prototype. Intact granite with drillability of grade X was taken as simulation strata, the effects of hammer mass, piston stroke and inputting flow rate on the drilling efficiency were studied. The test results show that increasing the hammer mass, piston stroke and inputting flow rate are beneficial to improve the drilling efficiency. The maximum ROP obtained in the tests is 5.19m/h, which is significantly more than that of conventional rotary drilling machines.

Abstract:This paper reviewed the research status of pipe automatic arranging system. In view of small capacity, poor stability and low placing efficiency of the drill pipe storage, a pipe arranging scheme was presented, pipes are arranged layer by layer separated by separator-plate with no gap. The scheme includes drill pipe conveying and sorting devices. Two automatic pipe conveying methods of inclined rolling conveyor and V-shaped groove conveying and sorting were designed. By the comparison of the advantages and disadvantages of these two options, V-shaped groove conveying and sorting device was selected to be the research direction. Based on the actual project parameters, the Adams dynamic simulation analysis was made on the precision error of the drill pipe in the conveying process, the rationality of the design was verified.

Abstract:According to the actual working conditions, the rig derrick vibration model is established and the dynamic load is obtained by testing experiments. Transient response analysis is made on K-type drilling rig derrick with ANSYS software, the results indicate that the variation of each part of the rig derrick has the character of simultaneity under the effect of dynamic load, yet the moments to achieve maximum value is different, which shows the lag of derrick response. The derrick is mainly on up-down vibration with a certain degree of torsion vibration. Displacement occurs mainly on the top of the derrick, while the torsion amplitude decreases gradually from top to bottom. The largest vibration displacement 108.33mm, the maximum bending moment 80990.8N·m and the maximum stress -0.16354E 09Pa satisfy the design requirements respectively. In the process of the transient vibration, torsion vibration attenuation is rapid; while X direction decay is the fastest among X, Y and Z directions, which is consistent with the actual situation. Therefore, the transient analysis on derrick by using the actual dynamic load provides reference basis for the derrick structure design and safety assessment.

Abstract:Requirements for wellbore trajectory are increasing along with the continuous development of drilling technology. Normal instruments based on geomagnetic positioning has been unable to meet the accuracy requirements, so a variety of near field magnetic guide system, such as MGT, RMRS and SmartMag target instrument, etc. are developed. On the basis of the type of emission source, this system can be divided into active measurement technology and passive measurement technology. Solenoid location system belongs to active measurement technology with the advantages of small data quantity and high temperature-resistance, this technology has been commercialized abroad, but there is no much research on it in China. The paper briefly introduces the theoretical model of solenoid measurement and explains the indoor experiment and error analysis. 144 points data were measured totally with the average total distance error of 4.9% and average plane projected distance error 5.6%; the feasibility of solenoid-location system is validated preliminarily.

Abstract:With the progress of oil exploration and development technology, rotary steerable drilling system is more and more applied in modern drilling. But when faced with more complex and higher curvature wellbore structure, the drilling operation requirements can not be fully met only by Xceed rotary steerable tools. In view of this situation, a special PDC bit with gauge structure was put forward, whose special lies in 1in standard gage in upper gage and 3in in lower gage with 0.6 degree taper. The computer simulation analysis shows that this PDC bit can not only improve the ability of BHA whipstocking, but also improve the drilling tool operation stability compared with conventional PDC bit. The field application in Bohai oilfield indicates the stronger whipstocking capacity of this PDC bit with special gauge structure to ensure the stability of rotary steerable tool and other downhole tools and slow down the downhole instrument failure caused by underground vibration.

Abstract:The development of large particle synthetic diamond technology makes it feasible technically and economically to manufacture surface set diamond bit. In this paper, numerical simulation study on the force, flow field and temperature field of φ75mm surface set synthetic diamond bit were made. The results indicate that diamond particles will be easily carbonized in the conditions of high bit weight and without drilling fluid circulation. With the cooling effect of drilling fluid, bit would get refrigeration in 0.006s during one round of bit rotation in 0.08s. Meanwhile, the erosion effect on bit body by hydraulic cavitation and solid particles in drilling fluid is very obvious. Duo to micro cracks in diamond particles, damage could occur in diamond particles even under the allowable stress. The comparative analysis shows that the diamonds on the outermost and the innermost nozzles of surface set diamond bit are prone to be damaged, so the design and manufacturing of surface set diamond bit should be strengthened.

Abstract:Under the guidance of the bionic theory, taking mole claws as bionic prototype, the high efficiency and wear resistance properties obtained from long-term evolution are introduced. CVD polycrystalline diamond cutters were selected as cutting unit and efficient bionic cutting teeth were prepared with vacuum hot pressing sintering process. By the contrast tests, the results reveal that the wear resistance of efficient bionic cutting teeth is increased by 23% compared with the conventional PDC teeth; the cutting efficiency is 1.49 times that of the conventional PDC teeth and 48% higher than bionic PDC teeth. It preliminarily proves the feasibility of the process of efficient bionic cutting teeth, which lays a solid foundation for further study on efficient cutting bit.

Abstract:Taking the example of pile foundation engineering of Sanguo Grand Theater of Xuchang City, the difficulties encountered in hard formations by ordinary long spiral drilling machine, hydraulic driving head drill and high weight and large torque dynamic head drill with frequency conversion technology are presented with the related countermeasures. The adaptability to formations are discussed for various models of long spiral pile hole drilling machine to provide reference for construction machinery selection in similar engineering.

Abstract:Steel pipe column reverse construction method is more and more widely applied in ultra large and ultra deep foundation pit, by the effective combination of bored pile and steel pipe column, the construction period and cost are greatly shortened. The verticality control is one of the important indicators of the construction quality of the steel pipe column. In order to meet the design requirements on the verticality of steel pipe column and ensure the construction quality, with the engineering case of steel pipe column grouting pile construction by the combination of auger drill and percussion drill in complex geological conditions, the paper summarizes and puts forward the technological process and control measures for reverse construction technology in steel pipe column grouting pile construction.

Abstract:Mountain rocks were encountered in the excavation of a construction project in urban scenic spot, rock slope blasting was to be carried out in this case. Pre-splitting blasting technology was used to reduce the blasting vibration damage and protect the integrity of the excavation profile. A pre-splitting blasting scheme was proposed based on the suitable design and the construction was carried out carefully in accordance with the scheme; meanwhile, the blasting vibration velocity of surrounding buildings was monitored. The results show that the vibration velocity of each monitoring point was much less than safety permission ranges with good macro blasting effect, which provides favorable excavation conditions for later blasting. This pre-splitting blasting technology has certain reference for the similar projects.

Abstract:The popularization of bore grouting pile technology gives rise to more intensified market competition, how to control the construction cost under the premise of good quality control is the key to achieve good economic benefits. With the case of the second phase project of Wuqing business district, the paper introduces the cost management and quality control in bored grouting pile construction. In cost management, how to prepare cost plan and effectively control the cost are described; in quality control, the control on bit diameter and pile diameter related to cost control as well as the quality of concrete at the top of pile are introduced.

Abstract:According to the particularity and severity of environmental protection situation for the nuclear geological prospecting industry, it is necessary to construct a safe production management system suitable for the geological prospecting units. Based on “nuclear” character, this system should be focused on the safety management of radiation source protection, radiation protection and environmental protection, use modern scientific and technological means to increase the safety assurance coefficient and promote closed-loop management level of hidden danger in field operation under the conditions with no technical and logistic support; carry forward the safety culture idea and improve the safety culture system with the characteristics of nuclear geological prospecting to make the safety management in the nuclear geological prospecting from the traditional experience management to the modern scientific management. With scientific management methods, the security risks in the production process can be controlled in the minimum range to ensure the sustainable development of nuclear geological prospecting industry.