Abstract:China’s dependence on foreign oil and gas is rising， and conventional technology optimization is difficult to meet the demand for greatly increasing production and reducing cost. We must break difficulties through revolutionary and disruptive innovation. In the shale gas revolution， based on the first principle thinking method， and focusing on the two goals of improving controlled reserves and reducing development costs， disruptive innovative technologies such as ultra-long horizontal well drilling， large fracturing， pad drilling and multi-layer three-dimensional development have been developed so as to reduce the drilling period and operation cost by more than 50%. It has realized the efficient development of Fuling Shale Gas Field—the first large shale gas field in China. The author extends the first principle thinking method to the fields of fracture cave carbonate rock reservoir and hot-dry rock geothermal energy development. The application of the first principle thinking method is an important way and method for the disruptive innovation of petroleum engineering technology in the future.

Abstract:As an emerging drilling technology， riserless mud recovery drilling technology has the advantages of safety and environmental protection， simplified well structure and reduced drilling risk. The traditional riserless mud recovery drilling technology relies on subsea pumps to lift drilling mud from the subsea wellhead to the deck surface， which requires extremely high lifting capacity and reliability of the subsea pumps. Therefore， for future deep-sea drilling， subsea pumps will be the bottleneck restricting the application of riserless mud recovery drilling technology. Drawing on the principle of onshore gas lift reverse circulation drilling， this paper explores the feasibility of use of gas lift technology in part or in whole to replace subsea pumps for mud recovery in terms of equipment availability， flow adjustability， applicable conditions， well control safety， etc. The results show that the performance of gas lift reverse circulation technology and related equipment can meet the requirements of RMR with the features of adjustable up-hole return flow and safety， and it is highly worthy of research.

Abstract:In recent years， with rolling out of marine natural gas hydrate exploration， in order to further increase the production and accelerate the pace of commercial exploitation of marine natural gas hydrate， the development of horizontal wells has become an important means for increasing production. However， in horizontal well drilling in shallow soft formation where shallow soft digenetic formation is present， the key technologies for borehole cleaning， wellbore stability， rheological property control， lubrication， friction reduction and leakage prevention in highly deviated well sections and horizontal well sections should be solved. In view of the technical difficulties on drilling fluid for horizontal wells in shallow soft formation， indoor research and field test were conducted to form a set of drilling fluid system and drilling fluid drilling process for horizontal well drilling in shallow soft formation， and several horizontal test wells were drilled in shallow soft formation on land to ensure the smooth well drilling and completion， which provides a large number of field test data for trial production of marine gas hydrate horizontal wells in China.

Abstract:Air lift reverse circulation drilling technology is a relatively mature drilling method in drilling engineering. With the characteristics of high drilling efficiency， long bit life， and good well quality， it has been widely used and promoted. However， air-lift reverse circulation continuous coring technology is still in the stage of exploratory research. The predecessors have done theoretical exploration tests on this technology， but continuous coring tests have not been carried out， and the existing double-wall drilling tools are also unable to meet the requirements for sealing and durability due to the quality and diameter of the returning cores. Therefore， it is necessary to further carry out theoretical research， parameter calculation， optimization of drilling tool design， and continuous coring test to explore the development prospects of this technology. The tests have been done， and the results show that the design of the large diameter double wall drilling tool is reliable and durable， and it can successfully obtain cores continuously. The cores were timely taken， free of pollution， highly representative， and can truly reflect the stratum level， depth， and particle gradation without repeated erosion and repeated fragmentation.

Abstract:Based on the requirements of green geiological exploration， this article mainly introduces the drilling technical characteristics and application advantages of portable modular drill. The application effect of the drill is analyzed based on 30 drilling holes in different kinds of geological conditions. The drilling technical methods are explored integrating the portable modular rig， the efficient rock crushed thin wall bit and the green drilling fluid， as a result improving the drilling quality and efficiency， reducing the adverse impact of the engineering activities on the natural environment， obtaining a better social and economic benefits. At the same time， the environmental protection and treatment measures in engineering activities are explored， and the management issues of green exploration work is discussed. At last， some suggestions are put forward for the wide application of drilling rig in the future， which provide a better guiding significance for the continuous promotion of green geological exploration work.

Abstract:In reference to the major national R & D project “the Development of Key Technology and Equipment of 5000m Geological Core Drill”， the main structure， the measurement and control system， the integrated active and passive rope arrangement system， and the winch auxiliary device of 5000m wire-line coring winch are introduced in detail， providing a new idea for the design and development of the wire-line coring winch. Notably， the winch auxiliary system is equipped with the depth detection and correction measurement device， the tension detection device， the wire-line cleaning device， the wire-line testing device， the core fishing downhole data acquisition device， etc.， which are used for accurately measuring hole depth and displaying the fishing device， identifying the downhole working condition of the inner tube assembly， cleaning drilling fluid on the surface of steel wire， monitoring the condition of the wire-line， and measuring the azimuth and inclination of the borehole. The wire-line coring winch designed in this paper was tested at depth of 4007.10m with fast retrieving and running in of the wireline for the whole coring process， achieving desired effect.

Abstract:The mast of coal bed methane truck-mounted rig is an important executive device， while the mast support frame is significant for supporting the mast， and its vibration stability determines the reliability of the mast. The finite element modal method is used to analyze the support frame under both the free vibration state and the prestressed state， and the numerical results and the change rule of the natural frequency and the modal shape are attained for the two states. Comparative analysis shows that the results for the two state are close but with slight difference， indicating that prestress is of little impact on vibration. At the same time， it is verified that the mast support frame will not generate resonance. Moreover， the modal results provide a theoretical support for the structural design of the frame， and a theoretical basis for topology design and in-depth dynamic analysis with crucial significance.

Abstract:The lost circulation incident in drilling operation has the characteristics of sudden occurrence and difficulty in treatment， which leads to low success rate of plugging and high cost. In order to solve this kind of problem quickly， accurately and efficiently， we must accurately predict lost circulation and put forward plugging measures. In this paper， the gradient boosted decision tree algorithm （GBDT） is used to study the loss circulation prediction model with the feasibility of GBDT as a lost circulation prediction model verified by analyzing some machine learning algorithms. The lost circulation case decision base is established by using case-based reasoning technology， and the Euclidean algorithm and LB_Keogh algorithm are used to search lost circulation cases to put forward corresponding lost circulation treatment measures. The reliability of similarity calculation has been verified through field cases.

Abstract:Controlled directional borehole drilling is often used in drilling engineering. In directional drilling， acquisition of borehole inclination and azimuth， installation angle of the deflecting tool， and hole bottom real time position（bore hole depth） are very important. Russian drillers have developed an automatic system integrating information， procedure and navigation used for directional drilling， which is of great significance for increasing drilling efficiency， guaranteeing borehole quality， and improving technical and economic indexes. It can provide some reference for Chinese counterparts.

Abstract:In order to improve drilling efficiency and make proper use of the heat generated during drilling， this paper investigates the thermo-mechanical rock fragmentation method by which ceramic material is added as a friction element to the impregnated diamond bit to improve the mechanical properties of the working layer. A new type of thermo-mechanical diamond bit was manufactured by calculating the size of the water ports and friction elements， and designing the bit matrix and structure， and compared with the conventional six-water-port and the three-water-way bits（the same structure as that of the thermo-mechanical diamond bit except for the friction element in the matrix） in lab drilling test. The results showed that， compared with the six-water-port and the three-water-port bits， the thermo-mechanical diamond bit with the friction element can generate heat and weaken the rock， and increase the drilling speed. At the same flow rate， the maximum ROP was 33.3% higher than that of the six-water-port bit. The matrix of the thermomechanical diamond bit had a small degree of wear than the three-water-port bit， and the thermo-mechanical diamond bit can be used for drilling highly abrasive formations.

Abstract:This article introduces field use of small-diameter wireline core drilling for geothermal survey hole ZK01 in the northern part of Dangshan County， Anhui province， where water-sensitive mudstone formation with a thickness of more than 600m was encountered. The mudstone was hydrated at the surface after encountering water， leading to the diameter shrinkage and the thick mud cake on the inner wall of the casing， which resulted in poor mud circulation and mud pump choking. In light of the characteristics of the small-diameter rope core drilling process， with analysis of the hole shrinkage characteristics and the causes for the mud cake on the inner wall of the casing， hydraulic control reaming drill bits were used with non-solid emulsified inhibitive drilling mud to achieve good results. The article describes the principle of the hydraulic control reaming bit， the precautions for reaming operation， the maintenance and preparation of non-solid emulsified inhibitive mud. The hydraulic control reaming bit was used for the first time in the small-diameter wire core drilling process， which can provide a good reference for subsequent drilling in similar formations.

Abstract:Green exploration is a prospecting mode， which， guided by the concept of green development in the process of prospecting， is intended to minimize the negative impact on the ecological environment， and to a certain extent， control the entire process of geological exploration to minimize the environmental impact so as to benefit both prospecting and environmental protection through the use of advanced exploration methods， processes， equipment， technology， and proper management. This article describes the practice and application results of green exploration in the Weiganping Phosphorus Mine in Fuquan City， analyzes the impact and damage of the construction project on the ecological environment， and summarizes the achievements in the implementation of green exploration， with a view to popularizing and applying it in future geological exploration work.

Abstract:Rock properties and in-situ stress can provide basic information for stimulated reservoir volume， and they affect fracture propagation evidently. Since shale has well developed lamination， the conventional methods with sonic velocity data， without considering special shale anisotropy， always express apparent error. A transverse isotropic model was presented to illustrate the unique rock properties of shale and a novel stress calculation method was investigated. The differences in rock mechanical parameters between isotropic model and anisotropic model were analyzed， and conversion of dynamic and static mechanical parameters was also presented. It was found the young’s modulus and the stress were greater than those from the conventional methods. The influence of initiation pressure from the anisotropic model was more obvious than that from the isotropic model. Fracturing simulation was performed with fracturing optimization software for shale formation in Jiaoshiba， Fuling. Numerical results show the fracture width is impacted noticeably and the anisotropy model underestimates the fracture height growth， which can provide technology support for in-situ fracturing treatment.

Abstract:Well Block Zi-201 is a key shale gas exploration and development area invested by PetroChina in the Rongxian area， Zigong city. Drilling of horizontal sections in this well block encountered many engineering challenges， mainly including serious borehole sloughing， hole instability， difficult well path control， low intersection rate of high-quality reservoirs， frequent sticking while tripping， which seriously restricted drilling safety and efficiency. In view of the above problems， the non-stabilizer mud moter was selected to optimize the BHA for reduction of the rigidity and friction of the BHA. At the same time， the compound plugging agent with plastic deformation particles and rigid plugging materials has been developed to improve the density， and strengthens the well wall support and sealing characteristics of the oil-based drilling fluid so as to ensure drilling safety and efficiency in the horizontal sections， and realize the normal completion of horizontal wells in Well Block Zi-201. Moreover， compared with previous drilling， the drilling period has been reduced by 34.12% with the effective intersection rate in high-quality reservoirs up to 100%， which provides a reference for safe and efficient drilling in the block and lays a foundation for increasing explored reserves and production.

Abstract:Temperature sensitive shape memory polymer is a kind of shape memory material. In its structure， there are fixed phases that remember the initial shape and reversible phases that can be cured and softened reversibly with temperature. In this paper， these properties of materials are applied to the cementing field of petroleum engineering. The temperature sensitive deformation characteristics of temperature sensitive polymer allows the particle deformation to be excited at high downhole temperature to form a large deformation， which provides a bridge structure for sealing and plugging the lost circulation layer； thus， solving the problems of poor leakage prevention and plugging effect of cementing slurry， and inability of the cement truck to pump large particles. The initial particle size of the temperature sensitive plugging material is 1mm. After reaching the temperature sensitive point， it deforms and expands in volume. The application temperature is 60 to 140℃， and the dosage is 0 to 2%BWOC； The temperature sensitive plugging cement slurry system prepared on these conditions can effectively seal the 2mm slotted plate at 7MPa. The temperature sensitive plugging cement slurry has been applied in North-209 well， North-8 well and North-213-1 well for cementing of the liner or oil bearing layers by the Northeast oil and gas branch company successively， especially in North 213-1 well where it effectively solved the problem of cementing leakage.

Abstract:The Wen-23 gas storage reservoir is a depleted sandstone type gas reservoir with a massive salt rock cover and a maximum temperature of 120°C at the bottom. To address severe leakage and formation contamination during drilling in the Wen23 reservoir， a leak-proof low-density micro-foam drilling fluid system with a temperature resistance of 120°C was developed. Test showed that the micro-foam drilling fluid system had a density change of only 0.04g/cm³ after 72hrs aging at 120°C. Only 325mL was required to reach a pressure of 10MPa or more with the permeability recovery value of the formation up to 87.9%. The micro-foam drilling fluid has been applied to 66 wells in the Wen-23 gas storage reservoir with the incidence of leakage only 13.6%， and the well wall was stable during the drilling operations. The leak-proof low-density microfoam drilling fluid with 120°C resistance has demonstrated good leak prevention in the construction of the Wen-23 gas storage reservoir with effective protection of the well wall stability and reduction of the damage to the reservoir， providing a guarantee for the safe and efficient development of the Wen23 gas storage reservoir.

Abstract:The horizontal section of the horizontal well in Daniudi and Dongsheng gas fields in northern Ordos is between 1000~2000m， and inclination-hold drilling is dominated. In order to ensure the inclination-maintaining effect， reduce the frequency of trajectory adjustment and reduce the slide drilling footage， the drilling assembly with the double stabilizers for inclination maintaining was mainly used to keep the inclination， and achieved good effect. However， the tight sandstone reservoirs in northern Ordos is highly heterogeneous， and the horizontal section often cuts through mudstone interlayers to make it necessary to adjust the trajectory， which led to the low build rate of the BHA assembly with the double stabilizers for inclination in the trajectory adjustment； thus， quick adjustment cannot be made to achieve the geological purpose. With analysis of the performance of different BHAs， the variable diameter stabilizers were applied to control their downhole working conditions. Through change of the outer diameter， they can change the drilling string， and its structure and effect to meet trajectory control， and realize inclination drilling along the whole horizontal section with quick and flexible trajectory adjustment. In Daniudi and Dongsheng gas fields in northern Ordos， the variable diameter stabilizers were applied to more than 10 wells in horizontal section drilling with the average ROP of 10.18m/h， and an increase of 24.6% in drilling rate for the horizontal section. The field results were good with improved drilling efficiency at horizontal sections， and can provide beneficial reference for improving drilling speed and efficiency at long horizontal section drilling in Ordos Basin.

Abstract:In view of the coal roadway， the high stress roadway and other small section roadways in the soft outburst coal seams in China’s coal mines， as well as the complex drilling conditions in narrow space， such as frequent giving way in the belt transportation roadway， by-passing of the roadway at work by the drill， and in light of the existing difficulties in movement and alignment of the drill in the coal mine drilling field， ZLY2500L crawler tunnel drill for coal mines is developed. At present， the commonly used containerized crawler drill has such defects： it can’t highly integrate underground mobility， compactness and high safety for operators； thus， leading to low gas drainage drilling efficiency， and poor adaptability to the complex drilling field and mine conditions. ZLY2500L drill can effectively improve drilling efficiency in small and medium-sized coal mines， increase mining output and reduce the labor intensity. It can be used for cross-seam and in-seam gas drainage drilling， water exploration and drainage， floor grouting and other drilling work. This paper mainly introduces the main technical parameters， the structural layout features and the hydraulic system of ZLY2500L crawler tunnel drill for coal mines. The test shows that it has a good application prospect for drilling in small and medium-sized coal mines.

Abstract:This article mainly introduces the design and verification test of ZHDN-SDR 150A high-frequency sonic drill， and provides theoretical basis and technical guidance for its application in the investigation and remediation of contaminated sites. The overall design scheme and the main performance parameters of the drill is discussed； meanwhile the structural design and technological innovation of the high-frequency sonic power head， the main components of the machine， and the auxiliary drilling tools are systematically analyzed. Verifying test was conducted for the drill in two different soil formations， and all parameters met the design requirements. The comparison of the verification results between the ZHDN-SDR 150A drill and similar ones at home and abroad shows that the drill stands at the domestically advanced level and runs neck and neck with international counterparts in terms of the main performance parameters and key equipment. The drill has prominent advantages with regard to vibration frequency， stratum applicability， and service life of auxiliary drilling tools， but has shortcomings such as decreasing drilling efficiency under the hyperthermal condition， scant intelligent and automation level. Therefore， it is necessary to further develop new materials with high temperature resistance and hardness， and to improve the remote wireless control system.

Abstract:In view of the lack of the function for cost calculation of foundation pit project in the current Revit software， this paper proposes using the Revit API secondary development technology is to realize the automatic calculation of foundation pit project cost based on the foundation pit project building information modeling （BIM） component family. Firstly， Revit platform is used to establish the BIM model of a foundation pit project and realize the parameterization of the family class of supporting structures of foundation pit projects. Then， with the knowledge of calculation process of foundation pit project cost， the Revit API secondary development technology is used to automatically obtain the parameters of various components in the BIM model of foundation pit project， and to realize the actual quantity calculation， quota application， display and output of data， etc.， based on the calculation formula of foundation pit project cost. Finally， taking a foundation pit project in Changsha city as an example， the automated cost calculation of the actual project is carried out to verify the feasibility of the above Revit-based foundation pit project cost calculation plug-in. The results show that the Revit cost calculation plug-in developed in this paper can achieve automatic cost calculation based on the imported BIM model of foundation pit project， and the results match well with manual calculation. The implementation of this technology makes up for the inadequacy of Revit software in the calculation of foundation pit project cost and foundation pit project cost， improves the efficiency of designers and lays a good foundation for further expanding the application of BIM technology in foundation pit projects.

Abstract:There was water seepage and frost boiling in the track plate at the local uplink of the ballastless track of Baicaoan Tunnel of the Tangbao railway line. Under dynamic loading of trains， the track plate sank unevenly. Railway track plate sinking was treated by grouting and glue injection： The 0.5m vertical depth of the broken rock layer under the inverted arch of the suspended track plate was injected with quick-setting cement slurry to achieve compaction and solidification of the broken rock layer at the bottom of the arch to improve and increase the rock bearing capacity of the base of the inverted arch； and a new 4.75^# high-strength foamed resin was injected into the bottom of the sinking track plate to lift the whole track plate until it returns to its original position. After grouting and glue injection， the vertical subsidence of the line has reached the designed stable value with the carrying capacity of the ballastless track restored.