Abstract:In the strategic seminar on basic research on geological engineering (prospecting engineering direction) held in 2013, it was proposed that the efforts should be made to make the prospecting engineering subject supported by the National Natural Science Foundation of China. And good news came in 2014, the National Natural Science Foundation of China formally listed prospecting engineering subject into funding direction, which was named “Exploration Technology and Geological Drilling Subject (D0219)”. This event has historical significance. In this paper, based on the analysis on the situation of funded projects of exploration technology and geological drilling as well as some neighboring subjects in 2015 and 2016, the units funded by NNSF, funds, project types and project contents were obtained. It is also pointed out that in the next period of time, the total number of application for support by NNSF will increase year by year, especially the youth fund projects. At the same time, the main challenges in current fund application were discussed.

Abstract:Compared to shallow water and onshore drilling, a number of technical difficulties are encountered in deepwater drilling and completion. Due to subsea high pressure and low temperature, hydrate has become a main threat to the safety of deepwater drilling and completion operation. Currently, OBM is the priority to prevent hydrate generation in deepwater drilling and completion. However, OBM is not environmental-friendly compared to WBM, so the latter was selected to use in ultra-deep water drilling. In view of the absence of similar experience, according to the actual situation of ultra-deep well in Lingshui block, the hydrate risk of 2 wells are simulated in order to identify hydrate generation condition; on the other hand, aiming at the risk of hydrate generation, proper hydrate inhibitor and drilling & completion fluid are selected. On the above basis, the matching technical scheme has been worked out. By the successful practice of deepwater drilling in Lingshui block, it is proved that WBM hydrate inhibition technology can well prevent hydrate generation during deepwater drilling operation and ensure operation safety, which has great reference and popularization value for the similar deep water well operation.

Abstract:The southwest of Jiaoshiba block in Fuling shale gas field is superimposed by multiple tectonic movements with strong deformation and complex fracture. The seismic curvature attribute indicates that the curvature of the main gas stratum is densely distributed. Although the curvature only indicates the extent of the strata bending deformation, the high curvature of the shale reservoir often predicts more micro-fractures development, which is favorable for shale reservoir forming a complex fracture network. However, if the natural micro-fractures were opened too much and too early, a large amount of fracturing fluid loss would be caused to result in limited fracture propagation and difficult sand pumping during the fracturing process. Compared with the main block, the fracturing curves show huge differences and the treatment difficulty greatly increased, too. Starting from the plane distribution of curvature, curvature density, directivity and the extension length, this paper tries to quantify the relationship between curvature and the effect of fracturing testing gas. Meanwhile, considering the influence of regional structure and fault impact, fracturing construction characteristics of different high curvature areas are analyzed and the corresponding adjustment measures are put forward, which provides the experience reference for the later-stage fracturing effect improvement and efficient gas field development.

Abstract:In this article, the analysis is made on the current cementing status and the causes of poor cementing quality in the western region of Yanchang oilfield. Based on the analysis, the slurry performance requirements for horizontal well cementing in this area are put forward. The optimized cement slurry system suitable for this area is selected, which has low filtration, zero-free liquid and high sedimentation stability, and its rheology is beneficial to improve the displacement efficiency; andefficiency; the formed cement stone has no shrinkage, micro-expansion and early strength characteristics, which can meet the requirements of horizontal well perforation post-fracturing and other projects construction. By all the above, a complete set of cement slurry system suitable for horizontal well cementing in the western area of Yanchang oilfield is formed.

Abstract:In the drilling of Wandi 1 well for basic geological survey of shale gas in Micangshan-Dabashan, the Permian Wujiaping formation thick layer of siliceous limestone and flint limestone were encountered, which were hard and compact with the development of fracture, dissolved fissure and karst caves. The serious circulation loss even no-return happened, which resulted in difficult drilling. Plugging while drilling, bridging material plugging, cement mortar plugging, colloid mud-cement slurry plugging and interception plugging technologies were adopted, no return of drilling fluid was solved.

Abstract:The geological conditions were extremely complicated with poor wall stability and severe sloughing problems in WFSD-4S hole of Wenchuan earthquake fault scientific drilling project. To solve the above problems, the drilling fluid system of bi-polymer anti-sloughing system was adopted in the drilling construction, which had excellent properties of stability, rheology, cuttings carrying and anti-sloughing, and presented effective application result in WFSD-4S hole drilling construction. Through optimizing the formula of drilling fluid and rationally adjusting and maintaining the performance parameters, the technical difficulties in WFSD-4S hole drilling were successfully solved, which laid a solid foundation for smooth completion of drilling construction.

Abstract:Shengtuo oilfield is the matured oil areas of Shengli oilfield. Oilfield development entered the later period, formation pressure disturbance is very common due to long period of waterflooding development, and the deployment of dense well pattern. To maintain the stable production, drilling infill wells in the existing well field. There is anti-collision and barrier-bypassing, wellbore trajectory control and drilling well control and other technical difficulties on infill wells, therefore, according to the actual drilling situation to develop technical plan and emergency plan, anti-collision wells use the "cone bit PDM BHA, pressure relief by stopping early water injection in injectors. Take one group (five wells) and one well as examples, engineering plans, wellbore trajectory control, BHA optimization and well control technology are analyzed, and corresponding measures are proposed, which solve the construction difficulties. The applications prove the scientific and feasible of the measures, and provide reference function for same kind of drilling in matured oilfield.

Abstract:The research is made on the application of air DTH hammer drilling technology for geothermal wells in the carbonate formation of Guizhou Province．In a well section of 10-1100m in depth with 216-406mm in diameter, cracks and fractures develop; water gushing, air leakage, block falling and difficult slag discharge frequently occur. In this paper, the DTH hammer equipment configuration, bottom hole assembly and drilling parameters in such complicated conditions are discussed; common problems in the drilling process with air DTH hammer drilling technology are analyzed and the corresponding technical measures are put forward. This paper also summarizes the drilling efficiency and economic benefit of air DTH hammer used for deep well drilling in the complex conditions of carbonate formation. The study results show that by reasonable equipment configuration and technical measures, the drilling efficiency of air DTH hammer can be effectively improved, which is great beneficial to deep geothermal wells of Guizhou Province.

Abstract:Based on the introduction of common stratum of non metallic mineral exploration, boring characteristics and wire-line core drilling, the causes of accidents such as sticking and pump suffocation are analyzed with the countermeasures. This paper summarizes the wire-line core drilling experience about flushing fluid types, performance requirements and maintenance management in soft and loose strata; emphatically presents SJP cement slurry and its application in grouting technology for borehole plugging.

Abstract:Lost circulation simulator is one of the key apparatus to formulate technical plans for lost circulation prevention and plugging. This new type medium pressure (0-1MPa) lost circulation simulator was designed to improve the complex structure, tedious test procedures, large volume mud and low data reappearance of existing lost circulation simulators. With this device, 1-3mm fracture leakage formation and 1-4mm cavern leakage formation can be simulated. The actual leakage area is totally 0.35-2.79cm2 with porosity of 1.81%-14.24%. By using this experimental device, the plugging slurry formulas, being composed of swelling plugging agents and walnut shells, etc., is obtained, which is suitable for different leakage formations. The sealing effect of plugging slurries not only depends on the size of fractures or cavern, but also on the total porosity of leakage formation. This lost circulation simulator and the plugging slurry formula can offer beneficial reference for lost circulation prevention and plugging in drilling process.

Abstract:Yaerxia oilfield is located in the anticline of west Yaerxia Cretaceous reservoir with high formation dip, much interlayer, strong abrasiveness and poor drillability. Deviation often occurs in vertical drilling and tool face stability is poor with serious back pressure in directional drilling, the selection of PDC bit types is difficult. Due to the poor compatibility with the formations, complicated downhole problems would be caused, which seriously restrict the drilling speed-increasing, the drilling fluid performance should be suitable. Aiming at the difficulties of restricting drilling speed-increasing, through the analysis on the field test results, this paper illustrates the drilling speed-increasing measures in Ya K block, including deviation control with straight well drilling, hydraulic oscillator test, PDC bit personalized test, bottom hole assembly selection and optimization of drilling fluid performance, etc. By the field tests, successful experience of the drilling speed-increasing has been accumulated for Ya K block.

Abstract:On the basis of analyzing the structure of screw drive chuck，a brief design calculation is made on the technical parameters of screw and nut. According to the application problems of chuck on large diameter drill, its structure is improved and perfected. With the reliable clamping, this type of chuck can meet the requirements of drilling rig and better technical and econom57ic results are achieved.

Abstract:In view of the service conditions of aluminum drill pipe in complex ultra-deep well drilling engineering, the main external drilling engineering factors of the corrosion behavior of aluminum alloy drill pipe are analyzed, the test and analysis on corrosion degree of the aluminum drill pipe engineering sample of Songke-2 well in the project of deep drilling of resources and environment in Songliao basin. The results show that the structure of drill pipe, wear and stress, drilling fluid medium as well as high temperature and high pressure are the main factors of corrosion; the corrosion at the connection point of aluminum rod and steel joint is the most serious and the aluminum rod body is the next; the corrosion resistance of pipe upsetting end is the best, the main components of the corrosion products are Al2O3 and Al (OH)3 phase.

Abstract:Great progress has been made in the research and efforts on diamond bits used in hard and compact, strong abrasive and mudstone formations. In hard and compact formation, by adding rare earth and selfsharpening materials in bit matrix and with low pressure bit structure design, the drilling speed can be up to 1.5-2.0m/h in hard and compact slipping formation with drillability less than grade 11 and the bit service life reaches 30-300m; in hard and abrasive formation, with the ultra high diamond working layer and optimized hydraulic structure design, ultrafine prealloyed powder and ultra wearresistant matrix performance, the POP and bit service life are increased by 20%-70% and 1.4-10 times respectively; in hard and compact mudstone formation, by the study on sharpteeth PDC bit and Baras bit, the drilling efficiency is increased by about 50%. For deep hard rock drilling in oil and gas field, compared with cone bit, NR826 series of impregnated diamond bit is used with screw drill, the ROP and bit service life are increased by 18%-85% and 5-8 times respectively. In addition, good progress has also been made in the research on PDC bit for offshore deep drilling in China.

Abstract:In processing of manufacturing the brazing diamond bit for vacuum activation brazing-sintering machine, when the temperature exceed 727℃，the bit body of steel 45 will react austenitic reaction and becomes easy to deform under brazing-sintering pressure because of the higher Ni-based brazing temperature. In order to maintain certain pressure to reduce the contact electric resistance and meet the requirements of constant brazing sintering temperature, by increasing the flow area of the bit steel body and reducing the resistance of the steel part to reduce the heating power and the temperature rise of the bit steel body, the plastic deformation of bit body can be effectively reduced.

Abstract:With the example of rockfall geological hazard in Beijing Baiquanshan scenic spot, this paper systematically introduces the hazard about the dangerous rock belt (mass) scale, dangerous rock characteristics, damage mode and damage degree, etc., and according to the geological hazard characteristics, development degree and the traffic conditions in the valleys, the analysis, comparison and selection are made on variety of treatment schemes, the final choice are cutting down earth on the upper anti-dip part of the dangerous zone to remove the dangerous rock mass, float stones on steep slope and loose rock mass and hanging active protection net. This scheme can be used as a treatment reference for the similar geological hazard of natural scenic spot in valley.

Abstract:In view of long length, small thickness and small integral rigidity of the diaphragm wall reinforcement cage of Harbin Metro Line 2, 15-point lifting hoisting method was adopted. By the checking calculation and selection on the parameters of the hanging points, wire rope and carrying poles, an economic, reasonable, scientific and safe hoisting method was provided, which has a certain reference for hoisting the similar diaphragm wall reinforcement cage.

Abstract:The excavation area of Hangzhou Xiaoshan Huarun Vientiane Project is very large and deep, and its location is very complex. The foundation pit is close to subway station and shield tunnel, river, large underground pipeline and buildings, etc. So it has a very high demand to control the deformation and leakage of foundation pit. How to successfully complete the construction of such projects worthy of extensive consideration and research. Based on the engineering construction examples, this paper summarizes and validates the applicability and reliability of the methods and technical measures adopted in the construction of the deep foundation pit under the complex environmental conditions and the analysis of the monitoring data, ensure the safety of foundation pit construction.