Abstract:FuseTek bit, a PDC Impregnated diamond hybrid bit, launched by NOV in 2013. It is suitable for drilling medium-hard to hard and abrasion formations. The FuseTek bits were widely used in Congo, Ecuador, China, Colombia, etc., Applications have shown that the FuseTek bits could increase the ROP obviously and bit life 1-3 times or more compared with PDC bit or roller cone bit . Pexus hybrid bit, a PDC Carbide hybrid bit, launched by Shear Bits in 2014,which used extensively in Western Canada to drill glacial till, comprised of a hard top layer of boulders, drilled by rotary carbide element and a soft bottom layer of sand and shales drilled by PDC cutters. The whole interval can be drilled in one run with one Pexus bit. Those three types of hybrid bits are significant for realization of “one bit, one well” in the future.

Abstract:Polycrystalline diamond compact bits have been popular with the customers for the high drilling efficiency. However, the service life of PDC bits have been restricted by stratum, hole depth and temperature. In recent years, many researches were carried out on improving the performance of cutters by experts both in China and abroad and a lot of achievements were received. This paper mainly introduces 2 new technologies of Smith bits-CDE and ONYX 360 degree rotary cutter. The practical drilling experiment shows that the drilling efficiency and service life have been obviously improved by using these 2 cutters.

Abstract:Jinshan gas field is located in Longfengshan structure and Changling fault depression; in the deep formations below Denglouku, drillability is poor with strong abrasiveness, which causes serious bit wear and inefficient use. On the basis of detailed and overall analysis on the adaptability of cone bit, PDC bit and impregnated diamond bit in high abrasive formation, an idea was put forward that by combining the technical advantages of high ROP of PDC bit and long footage of impregnated diamond bit, the design was carried out on PDC impregnated composite bit. Good effect is received in field application of the bit and reasonable suggestions are also put forward.

Abstract:The paper briefly analyzes the technical design of wire-line core drilling for deep geological hole and discusses the borehole structure design, technical risk factors and drilling safety. At the same time, the suggestions are made on the reasonable selection of diamond wire-line core drilling bit, the improvement of service life of wire-line core drill pipe and the evaluation method.

Abstract:ZR1 hot dry rock well has the characteristics of high temperature, high hardness and high abrasiveness. Polysulfonate drilling fluid system was selected in the construction for its good keeping of rheology and low filtration under high temperature and high pressure. By the analysis on the factors such as formation lithology and petrophysical property, the cone bit suitable for the well drilling in high hardness and high abrasive formation was selected and 1.24m/h average ROP was obtained. Through the experiment and practice, the cementing technology of high temperature（130℃）was mastered, water sealing and cementing quality is qualified by inspection. By the use of Chuan 5-4 type coring apparatus, coring operations were successfully completed in the high temperature, high pressure, and the broken formation with core recovery of 45%～83%.

Abstract:Based on the shape and direction of different fuzzy membership function's distributional curve, we selected the fuzzy distribution which is suitable to describe the cement slurry’s thickening time, liquidity index, API fluid loss, compressive strength. By comparing the actual performance of cement slurry designed and measured with actual cementing quality score, we got the parameters of related membership function . Taking the 5 wells as an example, the results obtained from this evaluation method are verified by existing literature and the average fitting error of the cementing quality of the site is raised to -3.34% by -12.26%, which means this method can be used as a practical and reliable method for optimization of cement slurry system and admixture.

Abstract:Pump pressure is one of the important parameters of diamond wire-line core drilling, which can reflect whether the operation is normal in the well. In order to further study the relationship between pump pressure fluctuation and the actual drilling operation for fast and safe drilling, on the basis of the actual pump pressure data of CUSD2 in Heyuanbei of Jiangxi and the related drilling data, a pressure loss calculation model for drilling circulation system is established. Comparing the fluctuation trend of theoretical pump pressure calculated by analysis model and actual pump pressure and using the model to the actual drilling, the pump pressure fluctuation in subsequent formation was predicted, it was found that 7MPa pump pressure safety value was no longer suitable for subsequent drilling, then the safety value was adjusted to 10MPa. The reliability was verified by the pump pressure fluctuation data of adjacent well. By the appropriate adjustment and correction, this theoretical model can be applied in wire-line core drilling in Heyuanbei and the whole Xiangshan area.

Abstract:The deep well drilling technology has a rapid development nowadays and becomes more mature. But some downhole accidents still inevitably happen in the construction process of geothermal wells. The accident causes should be seriously and carefully analyzed to develop target treatment programs and procedures for scientific and reasonable treatment. Taking the frequent hole sticking accident of geothermal well construction in Jinzhong as an engineering case, the paper analyzed different accident causes and worked out the sticking accident treatment methods. Based on the releasing mechanism, the performance of oil-based sticking releasing agent and configuration method were set up, injection volume was accurately calculated and key points of the injection technology were mastered in the operation, good effect of treatment was received.

Abstract:Stepped horizontal hole section is applied to stack-up 2 or more continual thin reservoirs with certain different height, which has the advantages of saving drilling investment and improving the production efficiency of the single well compared with ordinary directional well and horizontal well. The design of 3D stepped horizontal well trajectory was made by the analysis on the existing design model of stepped horizontal well and by the use of the constant tool face model. The upper and lower targets’ drift angle and azimuth angle are taken as the known quantity, the build-up rate and installation angle of deflecting tools as control factors. In addition, the drift angle and azimuth angle of flex point are the parameters to be computed. It is shown by the calculation sample that the designed 3D hole trajectory can be used for the design of stepped horizontal hole section.

Abstract:Fularchi oilfield in Qiqihar is rich in heavy oil resources with shallow and thin reservoir. Because of the restriction of surface conditions, vertical wells can not be applied in the development. 7 shallow horizontal wells were constructed in this block by 3rd drilling branch of Great Wall drilling company. Due to the short distance from the ground to the target layer in shallow horizontal drilling, some specific technical problems will be showed up during the process of drilling and completion. The difficulties during the construction are analyzed; safe, high quality and efficient drilling are achieved by the design of BHA, geology steering technology and optimized design of drilling fluid.

Abstract:Due to the characteristics of wellhead system in deepwater, liner hanging and tieback technologies are important in deepwater wells. The paper introduces the conventional liner tieback technology in deepwater both in China and abroad, elaborates in detail about the whole process, working principles and characteristics of the corresponding tools and the field application; puts forward the existing problems. Aiming at the existing problems and according to the common-used liner tieback technologies and the application situation as well as the development conditions in foreign countries, the development direction of two liner tieback technologies, being developed with different ideas, for deepwater drilling are presented.

Abstract:Good effects were received by the application of air reverse circulation continuous sampling technology with rational drilling equipments and drilling parameters in an auriferous conglomerate mine of Jilin. The practice shows that the recovery of rock samples is more than 98% in auriferous conglomerate by the use of air reverse circulation continuous sampling technology, where sampling is difficult; and along with DTH hammer technology, drilling efficiency in hard rocks can be improved with the cost being reduced. The paper introduces the construction equipment, pipe configuration and the process of air reverse circulation continuous sampling technology.

Abstract:Dongsheng gas field stepped into the development period in 2013. Along with gradual increase of horizontal well construction, lost circulation accidents occur frequently, single well plugging time in drilling cycle was roughly 8%～50%, which greatly restricted the drilling efficiency. The main leakage zone was in Liujiagou formation, the permeability loss happened when drilling fluid density was low with 3～5m3/h leakage velocity and crack leakage occurred when drilling fluid density was high with 20m3/h leakage velocity until annular return lost. The cracks would expand with the increase of the borehole liquid column pressure, which would cause repeated lost circulation. By the analysis on the leakage characteristics in J58P13H and plugging effect, the adaptability of the composite plugging method, plugging materials for large crack expansion and expansion pipe plugging method in fractured leakage plugging were explored in order to promote these methods in Dongsheng gas field.

Abstract:I38H is a prior drainage horizontal well in adjustment wells of Bohai oilfield, which was used for injection in later stage. 827.0m horizontal section was designed to satisfy injection-production relation of 3 wells in the surrounding. I38H is also a shallow displacement well with horizontal and vertical ratio of 2.47. For the safety of drilling operation, by the optimization of hole configuration, rational design of wellbore trajectory, the use of beck rotary steering tool and the reamer while drilling, well I38H drilling operation was successfully comleted.

Abstract:In view of the natural gas hydrate reservoir environment and relying on the research on the geological survey project “the design and technical study on in-situ drilling and sampling equipments for the water formations”, pressure-temperature core sampler for ocean was developed. On the basis of laboratory test, functional marine experiment was made on the developed drilling tools in shallow water and deep water successively. After the improvement, the functional test of pressure-temperature core sampler was made in 1392m deep sea with success, which lays a solid foundation for the ocean exploration and sampling of natural gas hydrate in China.

Abstract:By the exploration of pile foundation construction method of rotary drilling rig under the combination conditions of strong seepage and hard rock bed, the combined drilling method of anti-seepage is summed up and has been successfully applied in the engineering, which is by high pressure jet grouting with cross use of cone tubular drilling and pick coring tubular drilling of rotary drilling rig to break into rocks. Obvious effects have been received in the construction of large diameter bored grouting pile in hard rock bed.

Abstract:For the construction of diaphragm retaining wall trenching in sand-bearing soft soil layer, the construction quality will be affected by the collapse of side wall of trench. Water loss reducing, appropriate slurry viscosity increasing and collapse prevention are the key for wall protection in trenching. According to the geological conditions of a diaphragm retaining wall trenching engineering in Ningbo, partially hydrolyzed polyacrylamide (PHP), calcium polyacrylonitrile (CPAN) and potassium nitryl humate (NKHm) were taken as additives; the optional ratio of slurry performance was ascertained by the orthogonal test. The test results show that when using PHP, the amount of water loss is small with thin mud cake; CPAN and NKHm have evident effects on fluid loss control with moderate viscosity. The test result is applied in the engineering practice and the good effect of wall protection is received.

Abstract:There are many factors that affect the settlement of the landfill site foundation and the MSW body, great difference exists between direct use of the calculation method of the current standard and the actual actual practice. In order to reduce the influence of uneven settlement on the impermeable layer of landfill, determine the refuse storage and ensure the stability of the garbage heap, it is necessary to make research on settlement of MSW landfill site. The settlement of the landfill site includes the settlement of foundation and the settlement of MSW, and the latter is divided into main settlement and the second settlement, the main settlement time is shorter than the secondary one. Through the settlement calculation of the foundation soil of a landfill site in Baoji City, the maximum settlement difference is more than 100mm, which has a great adverse effect on impermeable layer of landfill site, and for the calculation of the settlement of MSW body, the modified calculation value is very close to the observed value of settlement. Considering the difference of the regions and the garbage composition, the accumulation of observed data is of great significance.

Abstract:For the comprehensive control of an unstable slope in Lanzhou, by the use of anti-slide pile, soil retaining plank, pre-stressed anchor cable, passive protection net, active protection net, cutting (drainage) channel and backfill planting, the optimal combination of safety benefit, ecological benefit and economic benefit were achieved. Based on the analysis on regional engineering geological conditions, the paper puts forward the overall design ideas and introduces the design of various engineering measures as well as the construction points.