Abstract:Exploration Engineering started publication in October 1957, which experienced 2 times of publication ceasing and resuming, periodical title changing and several times of sponsors changing in these 60 years. For all that, due to the longterm efforts and insistence of all the previous editors committees and editorial staffs, Exploration Engineering walks up to the present with extraordinary paces. While writing down the brilliant 60 years history, Exploration Engineering has become a great works with the development history record of exploration engineering technology in China presenting in front of us. Nowadays, the impacts from subject adjusting, evaluation system, emerging media and fund source have been bringing new challenges. Looking forward to the future, Exploration Engineering will continually adhere to the publication aims of focusing on practicality, combining theory with practice and learning advanced foreign experiences, and continually to be faithful recorders of the technical development of exploration engineering and rock & soil drilling and tunneling.

Abstract:Air reverse circulation drilling technology is a mature and advanced process abroad, but is relatively limited in China. Based on the research in recent years, especially a contract test between air reverse circulation drilling and core drilling was carried out in Xiaolonghe tin polymetallic deposit of Yunan Tengchong in 2015, the formation, mineralization bodies loss and construction efficiency were studied. The research shows that air reverse circulation sampling drilling has the advantages of efficient construction, low cost and good in geological prospecting. Meanwhile, the limitations of this technology in geological prospecting and some problems that need further study are also found out.

Abstract:Being located at the core area of Longshan dome, Longshan gold antimony deposit is one of the most representative gold antimony deposits in the central Hunan Province. All the boreholes in the previous construction are deviating seriously due to cleavage development. Based on the review of previous borehole data and related references, the statistical study and analysis on the reasons which caused borehole deviation and the deviation regularities are made, it is found that the borehole deviation distance is connected with borehole design depth, rock cleavage and construction technology. The prevention measures, such as hole location moving, inclination angle changing, vertical shaft azimuth adjusting and reasonable construction technology adopting, are put forward to reduce the borehole deviation, improve construction efficiency and ensure the borehole quality.

Abstract:In Cangzhou deep salt mine survey project, coring in 500～3290m section of the completed ZK002 was carried out. Deep and shallow double-hole was designed and geological and petroleum drilling equipments were used respectively. The conventional core drilling technology and drilling coring technology were combined to realize the complementary advantages of 2 types of equipment and different coring processes, the construction risk reducing, drilling quality ensuring, construction cost saving and construction period shortening.

Abstract:Due to the instability of shale gas horizontal well, oil-based drilling fluid leakage will cause a great economic loss; so the property requirement of oil-based drilling fluid system is higher and higher. In view of the above issues, a new type of strong plugging oil-based drilling fluid system has been developed by orthogonal test; the laboratory tests show that this system has excellent stain resistance, emulsifying stability, low fluid loss, good rheology, moderate viscosity and shear force. By the application of strong plugging oil-based drilling fluid system, well Jiaoye195-1HF shows that the leakage risk and loss cost are greatly reduced compared to well Jiaoye200-1HF which used common drilling fluid and several other wells; in this circumstance, 11 days are saved; this strong plugging drilling fluid system has good application prospect.

Abstract:A high-performance water-based drilling fluid system has been developed to solve the technical problems such as borehole cleaning, borehole stability, lubrication, anti-sticking and protection of oil and gas reservoirs in horizontal well construction. By the optimization of inhibitor, coating agent, filtrate reducer and other treatment agents, the high performance water-based drilling fluid formulations are ultimately determined, the performance experiments show that this drilling fluid system has stable performance with strong inhibition, lubricity, anti-pollution and reservoir protection capability, very good construction effects have been achieved in the field application of well Suping-5 of Sudeerte oilfield with stable wall, and no jamming in the tripping.

Abstract:Ultra-low density foam cement slurry is an effective technical measure to solve cementing leakage and improve cementing quality for low leakage pressure well. In addition to the foam cementing slurry development and the performance optimization, confirming static liquid column pressure (SLCP) at different annulus depth is necessary for foam cementing slurry application. With the help of real gas state equation, taking the influence on N2 filling volume by the variation of temperature and pressure into account, a mathematical model of SLCP and density of foam cement slurry together with the well depth was established, the implicit function is solved by iterative method and the program operation is realized by using VB language. The influence rules of gas content variation and well depth on foam cementing slurry density and SLCP are analyzed; the cementing slurry column structure design ideas for foam cement slurry are given for cementing leakage prevention and pressure stability which can be reference and theoretical basis for balanced pressure cementing design. This design method has been proved to be reliable by field application.

Abstract:As an important technical approach to control coal mine water hazard, drilling technology has been widely used. The application of coal mine water hazard control technologies, such as large diameter drainage well drilling, ground floor multi-branch horizontal wells by surface directional drilling and grouting reinforcement and reconstruction, underground directional drainage drilling, grouting to seal water inrush passage drilling and rapid rescue drilling of mine inrush disaster, has received good effects. Further development of drilling equipments for water control and the research on related drilling technologies should promote coal mine water hazard control.

Abstract:The horizontal well drilling passes through different strata in Shahejie formation of Bohai 35 oilfield, sandstone-mudstone ratio is unstable in the whole horizontal section with lots of interbedding, which is easy to lead to wall instability, difficulty of sand control pipe running, many blind pipes setting and serious screen pipe blockage in production. By the use of while-drilling tools, timely tracking and adjustments of borehole trajectory, drilling fluid system, drilling technology and some other aspects, the oil reservoir encountering rate in severe heterogeneous reservoir of deep strata in middle Bohai Sea has been effectively improved. Some operation methods and experiences can be reference to the field construction of severe heterogeneous reservoir horizontal well in deep strata.

Abstract:According to the experience in the design and construction application of small simple platform and “Sea-1” continental scientific drilling platform, the key structures of modular connection, lifting module and the pile shoe are designed for the multi-function geological survey platform in application. By the innovative design, the platform construction site limitation, transportation and convenient installation are solved and the efficiency of platform lifting and transportation are improved to adapt to the offshore engineering investigation project with short period and frequent relocation. Good application effects are received.

Abstract:In view of poor technological adaptability, low drilling efficiency and high energy consumption of engineering drill in construction process, a new full hydraulic engineering drill with load feedback system is introduced in this paper, which has the advantages of strong adaptability, energy saving, long drilling footage, large pulling force and automatically screwing. The field geological exploration results show that CTG-200 type full hydraulic can solve the difficulties in the construction with its characteristics of smooth crawler travel, stable performance, simple operation, short auxiliary feeding time, fast drilling tools lifting, convenient drilling tools removing and convenient construction for different hole positions in multi angles. The full hydraulic engineering drill is a new development direction to satisfy the demand of high efficiency and energy saving in today’s drilling market.

Abstract:For deep hole drilling in complex formation, failure of inner tube drilling tools fishing, failure of core breaking, core erosion and so on are easy to happen in using wire-line coring drilling technology. Combined with the development status of wire-line coring tool both in China and abroad and starting from the practical problems, the optimum design thoughts of drilling tool structure are given including coating drag reduction and vibratory plugging removal of core barrel, anti-jacking design of latch mechanism, friction increase between core lifter and core, increase of the flowing area inside the drilling tool, change of the flushing fluid flowing direction near the bit and so on in this paper in order to further improve the drilling efficiency of the wire-line coring tool in deep hole drilling.

Abstract:Hydraulic borehole mining has been researched and used abroad due to the advantages of high safety factor, engineering benefit and good ecological environment protection. Some related research institutes in China are also carrying out this research. On the basis of analyzing the hydraulic borehole mining equipment in foreign countries, pawl telescopic mining equipment with independent intellectual property rights is developed. In order to increase the single hole mining volume and reduce the mining cost of this mining equipment, not only mechanical telescopic gun, but also pawl mechanism are innovatively used to secure the protrusion angle of the water gun to expand the area of hydraulic mining seam. The preliminary field experiments show that this pawl telescopic mining equipment has reasonable structure design with high work reliability, the expected target is achieved by the effectively mining.

Abstract:In order to study the application effects of Beidou satellite measurement technology in the displacement monitoring for deep foundation pit construction, with an example of deep foundation pit project in Liuzhou City, the paper introduces the advantages of BDS system and conventional measuring method, the composition of foundation pit monitoring system, measuring points selection, monitoring methods and the effects. The research shows that GNSS technology, in which BDS is the key, can meet the requirements of accuracy and reliability, and is suitable for the displacement monitoring of foundation pit.

Abstract:Due to the natural and historical reasons, the soil structure is very different to that of inland area in Tangshan coastal area mainly with multi-layer soil structure and soft clay & sand soil in upper part, which leads to high cost of the single pile type with low efficiency, difficult construction and being easy to cause environmental pollution. According to this situation and considering the formation in this area, a set of construction method of flexible-rigid composite pile with cement rejection pile and pre-stressed concrete pipe pile is designed with construction difficulties and cost reduction, efficiency improvement and realization of energy saving and no mud recharge to be an environmental protection demonstration, which provides the reference for foundation engineering construction in this area.

Abstract:To further understand the effect of deep foundation pit excavation on surrounding pipelines and determine the pipeline displacement track model, with the background of a deep foundation pit project of Nanjing, the analysis is made on the actual monitoring data of pipeline displacement. The design, construction and monitoring schemes of the foundation pit project are introduced; on this basis, according to the construction process, this paper analyzes the variation rules of vertical settlement and horizontal displacement of 4 surrounding pipelines and explores the relationship between them to reveal pipeline displacement track. By the analysis, it is concluded that the vertical settlement happened prior to the horizontal displacement in time domain, along with the development of foundation pit construction, vertical settlement and horizontal displacement developed synchronously; after the completion of the second support construction for foundation pit, the vertical settlement exhibits plateaus and the horizontal displacement reduced; after the construction of the basement floor, both the horizontal settlement and vertical displacement tend to be stable. The track of the pipeline displacement track vertically closer to the foundation pit side wall is a cubic polynomial curve and the pipeline displacement track far from the foundation pit side wall moves straightly toward the foot of the pit.

Abstract:Anisotropic rocks are often encountered in drilling engineering construction; while drilling, the anisotropic rocks strengths in different directions are not the same. The rocks that are vertical to the strata are broken easily, but those drilling in other directions have big fragmentation resistance, therefore the core part of rock is deformed into ellipsoidal shape by extrusion. Axial drilling load is mainly used for overcoming internal friction resistance in the rock and the reactions from the rock fragmentation. Under the action of vertical component of rock reaction, overturning moment is produced to the drill bit; under the action of the overturning moment, drill bit is deflected and borehole is deviated, which have direct influence on the penetration rate and hole quality. Doctor Скоромных В.В., who is a Russian professor, and some others have made a lot of studies in resolving the overturning moment, a new idea of drill bit design is proposed for drilling in the anisotropic rocks.

Abstract:For being situated in a mined out area, the foundation was unstable in CK3 contract section of Yangcheng-Manghe section of Yangcheng-Jiyuan expressway, the full filling pressure grouting method was used in the treatment. Because mud was restricted and hole completion was difficult in gravel layer, high pressure DTH hammer was applied with good effect. This paper summarizes the construction experience of grouting boring in mined-out area with high air-pressure DTH drilling technology in grouting hole design, equipments selection, BHA & drilling technology and dust & pollution control, which can be reference to the mined-out area treatment for the similar project.