Abstract:The formations are mainly of steep occurrence of phyllite in Tiziya-Fuziling lead-zinc polymetallic ore area, locally containing calcite or quartz veins with fault fracture zone development and poor wall stability, the design requirements could not be met because of common severe drilling hole bending. The hole deviation prevention, deviation correction and slurry protection are the major construction technical problems in this mining area. This paper introduces the technical measures taken in hole deviation prevention, directional deflection, wall protection and plugging, as well as the results achieved.

Abstract:Aiming at the difficulty in water sample collection caused by small diameter monitoring channel of CMT monitoring well, a new type of portable motorized inertial pump is developed and its reliability is analyzed. The tests and studies are made on the influence of motor speed, sampling depth, channel diameter and sampling tube specifications on sampling speed, which lays the foundation for retrofitting portable motorized inertial pump and provides reference for the sampling of small diameter monitoring wells.

Abstract:In 2016, land gas hydrate trial-produce has been carried out successfully in Muli basin, Qinghai. It is the first time that the technology of horizontally butted well has been applied in gas hydrate trial-produce and remarkable results have been achieved. Complex stratum of drilling area brought great difficulty and risk to the horizontally butted well drilling. Drill pipe sticking appeared several times during the drilling process, this paper mainly introduces and analyzes in detail on the main reason of drill pipe sticking with the corresponding jam release methods.

Abstract:Drilling equipment and process method are the core of drilling engineering technology and the former is the basis and hardware condition of drilling technology. Different types of drilling equipment are required in the different construction conditions. Drilling equipment is the general name of the necessary equipment for drilling construction, such as drilling rig, mud pump, derrick, power and other technical equipments. Based on the analysis on the influence of equipment configuration on drilling efficiency, this paper discusses the selection and allocation of key equipments and tools for deep geological core drilling and puts forward some suggestions for the optimizing the key equipments in deep hole core drilling.

Abstract:SAGD twin well is an important technology for producing heavy crude oil, which demands a lot controlling about the two wells’ trajectory. It’s good to improve the drilling trajectory measuring accuracy and efficiency with the help of MGT technology instead of MWD. At present, there is no report on the application of similar mature instruments made in China. This article mainly introduces an experiment performed on the ground, which tries to find the relationship between the trajectory accuracy and magnetic source inside a casing to provide data and technical support to the practical application. A solenoid which is put into a 139.7mm casing as a magnetic emitter and a magnetic sensor are placed to simulate real drilling situations of SAGD, the relative positions of the twin well are finally worked out by computer analytic data. In the experiment, the relative position between the sensor and the casing is continuously changed to simulate the actual situation of bit drilling. 18 trajectory patterns are collected with 198 point sites data. Before correction, the average errors of calculated total distance was about 7% and the plane errors are about 9.4%; after correction, the errors are reduced to only half the previous ones. The results show that the calculated points can really reflect the actual direction of the trajectory.

Abstract:In the regional geological survey of urban geology and hydrogeology in coastal area of Jiangsu Province, full coring drilling is the main field work means. The sedimentary layers thickness are of 300～500m inequality, the deepest place is up to more than 800m. There is no precedent of coring in such thick sedimentary layer with such requirement in Jiangsu Province even in China. According to a drilling construction case, this paper summarizes the full coring drilling construction technology in very thick gravel layer of Jiangsu coastal area starting with drilling equipments selection, construction technologies determination and mud control technology, which could be referred in similar drilling projects in the future.

Abstract:By analyzing the purpose and requirements of the shale gas geological exploration well, the applicability of small diameter core drilling technology in this field is determined. Proceeding from the physical and chemical characteristics of shale and shale gas reservoir, the technical research on small diameter core drilling technology applied in this field is carried out. The analysis on the main points control is made for small diameter core drilling technology differing from conventional situation processing from equipments selection, management and technology to ensure the economy and safety of shale gas geology exploration well and further improve the small diameter core drilling technology system.32

Abstract:In order to reduce the high holing abandoned rate lasted for years in the construction of the southwest of Tarim, this paper introduces the drilling construction technology of Yundi well-1 in the southwest depression of Tarim basin, the process of dealing with complicated downhole situation and the on-site technical management measures; summarizes the technology characteristics of drilling in the complex strata of Tuyon basin in southwestern Tarim depression to form a complete set of feasible construction methods and technical management program, the construction problems in this region are basically solved.

Abstract:The construction is difficult in Dacun exploration area in Guxu mining area of South Sichuan coal field with Karst cave and crack development, coal seam collapse and the wall damage by gas pressure test and CBM well test. In order to deal with the above difficulties, the suitable construction processes and technical measures were adopted in borehole structure design, bit selection and the usage of drilling fluid and casing, the good effects ensured the smooth drilling construction in this area.

Abstract:The various complex formations with folds and faults development made the drilling construction very difficult in Baijian mining area, several drilling technologies are adopted, including ball-down single pipe drilling, PDC wire-line core drilling, drilling with casing and diamond wire-line core drilling. According to the different formation conditions, different slurry preparation schemes are adopted and flexibly used in the construction process with good construction effects and experience.

Abstract:The designed hole depth was 2000m for Dongfenghu geothermal well exploration construction project in Benxi of Liaoning Province, the well completion diameter was required to be 100mm. The construction was difficult because of the deep drilling and large completion diameter, complicated ground conditions with broken formation, leakage and caving development. This paper introduces the construction process, mainly including customized non-standard bit drilling, broken drill pipe treatment, hole reaming by pre-posed bit, cementing technology and drilling through cement plug, which can be reference for the similar projects.

Abstract:In the geological exploration of solid mineral resources in China, diamond drilling is a main drilling method. In the diamond drilling, rock fragmentation is mainly realized by the diamonds set in bit crown. Along with the rock fragmentation at the bottom hole and the borehole depth increasing, the diamond face exposure is worn, which has direct influence on drilling rate and bit footage until the bit is discarded. Therefore the sharpening of the diamond face exposure should be paid a special attention. Russian doctor Спирин В.И. and some others have made a lot of studies on sharpening the diamond face exposure by using electrochemical principle in order to improve the penetration rate and bit footage; and based on this principle, the portable diamond bit electrochemical sharpening device has been developed for field application with very good technical and economic effects.

Abstract:The soil samples are required to be undisturbed in scientific drilling of Hemudu-Tianluoshan site in Ningbo. Due to the special strata lithology in Ninbo area, it is difficult to meet the requirements with the traditional thick-wall and thin-wall soil samplers. In this case, a new type double-tube core barrel is developed, and the mud technology is also improved. The application shows that the core recovery has been improved with high quality soil and rock samples, the disturbance on undisturbed soil are largely decreased. This new type double-tube core drilling tool, with PVC inner tube and one-way valve, large water outlet and proud exposure bit, has advantages of high efficiency, high performance price ratio and good operability.

Abstract:The hot dry rock resource is mainly made up of volcanic with high temperature and poor drillability. In order to resolve the difficulties of low drilling speed and serious drilling tools wear, a set of φ127mm high-temperature turbodrill is designed and manufactured, which was tested in a hot dry rock well, the ROP were increased by 30.3% and 98.5% compared with φ165mm PDM + diamond bit and rotary table matching cone bit respectively. The experiment results show that this φ127mm turbodrill has reasonable structure design and is suitable for the high-temperature hot dry rock drilling.

Abstract:Expandable convoluted tubing technology has been applied in the field of petroleum drilling both in China and abroad, but the research on small diameter expandable convoluted tubing in the field of geological drilling has little effect. In this case, mall diameter expandable convoluted tubing technology for geological drilling industry is researched and developed, which has been successfully applied in sealing up the leaky stratum in ZK3-1 drilling in Sichuan coal survey, then drilling to the final depth. This application is a new field for the accident treatment in geological drilling industry, which fills the gap in the field of small diameter expandable convoluted tubing in China.

Abstract:This paper mainly introduces the working principles and construction steps of hydraulic pipe-fracturing technology. Combining with the construction case in Changchun sewage pipeline replacement, the detail exposition are given to the construction steps, the difficult problems and treatment measures as well as the construction precautions for the application of the hydraulic pipe-fracturing technology in sewage pipeline in-situ replacement. In this construction, hydraulic pipe-fracturing technology showed its unique advantages with good effects, the experience can be reference to the trenchless pipe replacement.

Abstract:The model barrel experiments were carried out on different drainage methods for the waste mud of bored pile in an engineering project in Wenzhou with the same chemical agent combined with vacuum preloading, the comparison analysis was made on drainage rate, total amount of drainage and water content. The experiments found that with the improved drainage methods, the water content of waste mud is reduced from original 180%～ 190% to 60%～80% in a short time (within 80h), which shows remarkable effect of waste mud disposal by improved drainage methods of additive agent combined with vacuum preloading.

Abstract:In recent years, concrete settlement, water emitting and sand exuding often appeared on the pile top concrete in the bored grouting piles construction and inspection processes in Wenzhou City, which seriously affected the engineering quality. From the view point of factors of environment, material and technology and combined with the bore grouting pile construction experience, the forming causes of the above mentioned phenomena are analyzed respectively and the relevant explanations are presented in this article, the correlation between these 3 phenomena is also explained.

Abstract:With the engineering case of bored grouting pile construction in the work area at north band of Lingkun bridge for Wenzhou regional railway, the analysis and discussion are made on the technical measures adopted to overcome difficulties of rotary drilling rig construction in over-water holing at the estuary and the engineering effects. The difficulties are involved as strong tidy sea area encountered, large depth of bored pile, very unstable flow plastic formation at the upper part, the pile bottom extending deep into the pebble layer with sudden mud leakage possibility and hole collapse easily caused by tidal effect, and so on.