Abstract:China is very rich in shale gas resources with great development potential. It is possible to form a series of complete drilling and completion technology for shale gas development through borrowing, converting and utilizing of wellproven conventional oil and gas development technology. Horizontal drilling has dominated the drilling methods for shale gas development, and integrated with rotary steerable drilling, MWD/LWD, 3-D seismic survey, and underbalanced drilling, it will increase development efficiency. Hydraulic fracturing is a main technique for stimulation of shale gas reservoirs. Advances in slick water fracturing, refracturing, synchronized fracturing, etc., will make shale gas development more promising.

Abstract:The vertical depth of Heyuanbei deep drilling hole CUSD2 in xiangshan area was designed for 1800m and it spent 119 days (the drilling started on November 28, 2014 to March 26, 2015)to have the drilling depth of 1535.02m, reaching the geological target horizon. The first domestic XY-8DB electric drive spindle coring rig was chosen for this project construction, with P size (122mm in diameter) core drilling to 1535.02m. The paper introduces the drilling construction technology for this borehole.

Abstract:According to the complex geological conditions of deep tight gas reservoir in Daqing oilfield, fracture developing in conglomerate and volcano rocks in the reservoir and strong water sensitivity; leakage, collapse, diameter shrinkage and drilling fluid property degradation while drilling at high temperature; friction, cuttings carrying and reservoir pollution in deep horizontal well drilling, as well as the high cost and late environmental protection pressure caused by the use of oil-based drilling fluid, on the basis of the analysis and summary of the previous experience, starting from the geological characteristics in tight gas reservoir and difficult points of deep horizontal well drilling, the technical measures for drilling fluid were clear. Though the study on inhibition of polyamine & polyether polyol and anti-sloughing plugging agent and working with new efficient independent developed drilling sealing material, a set of double poly amine drilling fluid technology was developed, which is suitable for horizontal well construction in deep tight gas reservoir. The laboratory studies and field application show that this drilling fluid system has ability of strong sealing

Abstract:For steep formation, soft-hard interbeded layer and burnt rock exist in Baiyanghe coalbed methane mining area in Fukang of Xinjiang, drilling deflection and hole collapse are caused. Pneumatic DTH hammer and EM-MWD directional drilling technology were used to solve these difficult problems; the construction efficiency was more than 3 times than the general drilling speed.

Abstract:Hard formation was encountered in Yanyingzi geothermal well of Chengde where there were deviating force and complex lithology, the construction was difficult. Screw drill was adopted in accident treatment, deviation correction and compound drilling; the effects of screw drill application under these 3 working conditions are analyzed. Serious wear of conventional bit in hard rock drilling, low drilling speed and drilling collar fracture are solved by MD bit, and some improvement suggestions are put forward.

Abstract:Well ZK1146 is a scientific drilling hole for Qilianshan gold mine, which is located in Jinying mining area of Gansu Province; the mining area contains formations of sandstone, mudstone, carbonaceous slate and phyllite with poor lithology and cementation, large dip angle, disordered bedding and low wall strength. Based on this situation, the solid free film-forming and anti-sloughing drilling fluid system was developed with inhibitory and cementation to solve the drilling difficulties in broken, collapse and water sensitive formations. Good effects of borehole wall and core protection have been obtained in well ZK1146, the mudstone dispersing is effectively prevented.

Abstract:The Support Vector Machine (SVM), Bayes discriminant analysis and multiple regression analysis were used for diagnosis and prediction of sticking. The discriminant model of stick type was built based on pattern recognition theory. The calculation analysis on the sticking data of northeastern Sichuan was made, it was indicated that the misjudgment rate for discriminant result of SVM, Bayes discriminant analysis and multiple regression analysis was 1.92%, 11.52% and 61.54%. The accuracy of SVM recognition result was the highest, but its discriminant equation is complex and the contribution of each component to the result could not be intuitively seen; while the equation of multiple regression analysis is simple, which could intuitively show the close degree between each component and sticking, but the accuracy of recognition result was lower. The accuracy of Bayes discriminant analysis was between the above two, but the discriminant accuracy is closely related to the number of discriminant.

Abstract:Drilling tool falling is a typical downhole accident; it will spend time, manpower and material resources for dealing. The careful drilling tool detection, inspection and good-condition of drilling tool are the main insurance to prevent the accident. However, due to some objective factors, the accident still occurs. The paper presents a typical case of I27H well in Bohai oilfield, drilling tool dropped down to the hole bottom in the drilling process of a 406.4mm well, based on the brief introduction of this well and the accident process, the difficulties of drilling tool fishing in large diameter hole in middle shallow were presented and the feasible fishing scheme was put forward with successful fish operation.

Abstract:Geothermal resources is a clean energy, which is mainly exploited with geothermal well. The quality and service life of the well will directly affect the whole operation cost and efficiency of heating, spring bathing, planting and breeding. The reduced water amount even no water will occur because of the blockage in filter tubes or mining layers (fissures or karst). These blockage types can be divided into physical and chemical (bacterial) blockage. The causes of various types of blockage are analyzed in detail and the special solutions are proposed according to those different engineering cases.

Abstract:The article introduced CSD1800A drilling machine with all hydraulic power head about its application effect in Qinghai-Tibet Plateau, and analyzed its advantages. By the comparison of application effects of drilling machines both in China and abroad, it is proved that CSD1800A is an economical and practical drilling machine for medium-length hole.

Abstract:All hydraulic drill power-head used in coal mine is mainly composed of hydraulic motor and gearbox, and the vibration intensity of gear transmission directly affects the output capability of power-head. Take ZYWL-2600R soft coal seam spiral drill as the research object, on the basis of single degree of freedom torsion vibration model of gear pair, the vibration acceleration of meshing line as optimization objective, a dynamic optimization design model of power-head gear pair is established and the graphical interface of the optimization program is developed with the help of Matlab optimization toolbox and GUI tools to figure out the minimum macroscopic design parameters of vibration, which provides the reference to dynamic optimization design of high speed drill power-head. The results show that the gear mesh stiffness of the optimized gear pair is significantly increased accompanied with the effective improvement of vibration characteristics of gear transmission.

Abstract:The current situation of coring drill pipe and friction welding technology is presented. Through the comparison of 3 kinds of deep hole wire-line coring drill pipe connection structure and production process, analysis was made on the advantages of the use of thin-wall wire-line coring drill pipe by friction welding in deep hole drilling. The paper introduces the structure design and the machining process of φ73mm×5mm thin-wall wire-line coring drill pipe by friction welding and puts forward the main technical problems and matters needing attention in the welding process. The main technical parameters of the drill pipe are obtained through the tension and torque tests, the maximum tensile force and torque are 580kN and 5500N·m respectively, and the recommended use depth is 2000～3000m.

Abstract:Mainly designed for large diameter foundation grouting pile construction, YCJF-25 percussive and reverse circulation hydraulic rig has the advantages of large rock breaking energy, high rock breaking efficiency, fast discharging ability and repeated bottom cuttings breaking can be effectively avoided. The paper introduces YCJF-25 percussive and reverse circulation hydraulic rig about its performance parameters, illustrates its structure features and analyzes its construction efficiency.

Abstract:Rock-embedding is more and more required in diaphragm wall engineering. According to the low rock embedding efficiency of the grab widely used at this stage, take the characteristics of grabbed formation as the starting point, the analysis was made on the reasons of low rock embedding efficiency; with rock fragmentation theory as theoretical basis, some improvement suggestions were put forward in the grab weight, cylinder closing force, bucket teeth arrangement and grabbing mode.

Abstract:The main elements of the dismountable support system for working pit are introduced including 2 parts of vertical hollow column and special steel plate with uneven thickness. The vertical hollow column can be laid into the expected depth by force transfer device, air hammer or small drill. The special steel plate is laid layer by layer through stratified excavation. Structure type, working principle, construction technology and design theory are introduced and the design process is described combined with engineering example. The feasibility of column selection and rationality of the special steel plate size are verified according to the actual calculation to avoid the complexity of traditional construction technology, save engineering materials, improve construction efficiency and reduce project cost.

Abstract:Based on the detailed geological investigation of the debris flow gully in Qianhuoshiling village, the stone landslide masonry dam for the debris flow control was designed; the stability of dam was calculated to learn the related parameters, the anti-slide stability coefficients and anti-overturning stability & foundation stability under three kinds of design condition. By the design and implementation of the program, the influence of the debris flow could be effectively weakened to protect the safety of life and property of the villagers.

Abstract:Penetration rate, bit footage and cost per meter drilling are main technical and economical indexes of exploration engineering. The indexes depend upon bit selected, drilling parameters used and operation technology. The selected bit should be suitable for hardness, abrasiveness (drillability) of rock to be penetrated. The operation technology mainly depends upon qualification and experience of driller. And selection, definition and their rational combination of the drilling parameters are an important factor, which can not be neglected. Concept about critical drilling parameters has been put. The critical parameters are a red line not to pass, otherwise accident will occur. In normal parameters drilling weight on bit and rotary speed should be rationally combined and flow rate of fluid should guarantee cuttings in the bottom of the hole in normal state in order to obtain good technical and economical results. It is suggested to adjust rational combination of weight on bit and rotary speed and control the appearance of critical drilling parameters with wattmeter seriously and quantity of the drilling fluid in the bottle of the hole with flow meter and to combine drilling with experience with drilling with science.

Abstract:Ultra-high pressure grouting of hydropower project building is a new subject. The natural fall of the second pumped storage power station of Tianhuangping is about 730m, 12MPa grouting experiment was carried out in PDX1 testing tunnel of Tianhuangping to study and explore the impact of high water head in hydraulic tunnel on the integrity of tunnel surrounding rocks and deformation resistance. By the smooth progress of the entire filling based on the appropriate construction methods and measures, reasonable grouting procedures and parameters were obtained, which could be the practical basis of large concrete lining grouting with high pressure water head.