Hasil untuk "Oils, fats, and waxes"

Taping He, Wenju Wang, Xiaobin Xie et al.

Abstract The sedimentary mechanisms and depositional processes of deep-water gravity flows in lacustrine basins remain incompletely understood, posing challenges for accurate reservoir prediction in continental rift basins. This study investigates the Triassic Yanchang Formation in the Ordos Basin to elucidate the genetic processes and evolutionary mechanisms of deep-lake gravity flow deposits. Through systematic core observations, grain size analysis (including mean size, sorting, skewness and kurtosis), and sedimentary facies analysis, we identified four distinct gravity flow types: (1) sandy debris flows, (2) muddy debris flows, (3) turbidity currents, and (4) slumps. Quantitative grain size parameters reveal significant differences among these facies, with mean grain size ranging from 1.19Φ to 3.53Φ. Three primary triggering mechanisms are recognized: seismic events (seismites), volcanic events (tuffaceous layers), and anoxic events ("Zhangjiatan" shales), with seismic and volcanic events exerting particularly strong influences. A new depositional pattern is proposed, detailing the complete evolutionary sequence from slope failure initiation to final deposition, encompassing the sliding-slumping-debris flow-turbidity current transition. This study advances understanding by: (1) establishing quantitative discriminators for different gravity flow types, (2) clarifying the causal relationships between external triggers and flow deposition, and (3) providing a comprehensive evolutionary framework for lacustrine gravity flow systems. These findings significantly enhance the ability to predict deep-lacustrine sedimentary architectures and hydrocarbon reservoirs, offering valuable insights for exploration in analogous rift basins.

Qingxiu Zeng, Peng Sun, Xingchao Jiang et al.

Despite over 40 years of exploration focusing on the deep to ultra-deep Ordovician carbonates as major hydrocarbon targets in the Tarim Basin, the identification of their source rocks remains elusive. Based on biomarkers, carbon and sulfur isotopes of hydrocarbons, the primary source for the Ordovician petroleum system has been attributed mainly to the lower Cambrian shales, although some oils were likely contributed from the Lower Ordovician source rocks. However, the current understanding of the evolution of the Ordovician petroleum system remains rudimentary, largely due to the complex interplay of multi-source (i.e., the widespread Precambrian shales) hydrocarbon inputs, diagenetic alterations, and tectonic processes over geological time. This study systematically investigates the molecular geochemistry of reservoir bitumen within the Ordovician carbonates from Tabei uplift, coupled with bitumen from the Sinian units at the western edge of the Tarim Basin. Our results indicate that the ion chromatography-mass spectrometry spectra and the saturated to aromatic hydrocarbons ratio of Ordovician reservoir bitumen closely resemble those of Sinian bitumen, as well as the published data of Sinian shales. This coupling linkage is revealed by cross-plots and ternary phase diagrams of various biomarker parameters, which can effectively distinguish the Sinian sources from other sources, i.e., the Lower Cambrian and Ordovician, for the Ordovician reservoir bitumen. Specifically, the ∑n-C21-/∑n-C22+, Pr/Ph, G/C31H22S, C23/C21TT ratios are effective indexes to differentiate these source rocks. By compiling the published organic geochemistry data of oils, it appears to infer that approximately 8.1% of the present-day oils produced from the Ordovician carbonates likely contain some proportion of Sinian-sourced oils. The recognition of Sinian sourced oils contributing to the paleo- and present-day Ordovician petroleum system offers valuable insights for the exploration of deep-ultra deep carbonates in the Tarim Basin, emphasizing the need to consider Precambrian shales as a significant hydrocarbon source.

Mohammad Reza Esmaeilinasab, Mastaneh Hajipour, Abbas Shahrabadi et al.

Abstract Smart water injection into oil fields is an efficient EOR method but has significant challenges due to incompatibility between the formation brine and the injecting water. The presence of reactive ions in smart water can change the wettability of reservoir rock to increase oil production. However, the possibility of formation damage due to inorganic scales may increase. In this research, static and dynamic experiments were conducted to investigate the competition between rock wettability alteration and formation damage due to smart water injection. The experiments were performed in two parts including waters compatibility tests and rock wettability measurements for various concentrations of potential-determining ions in smart water. The crystal size and morphology of the sulfate scales were inspected visually using scanning electron microscopy images. In static compatibility tests, the maximum amount of sulfate scales was detected in the mixture containing 40% injection water. The experimental data indicated that the simultaneous increase in the concentration of sulfate and magnesium ions improves the carbonate rock wettability 18% more compared to increasing sulfate concentration alone. As a result, SW_1Ca.2 Mg.1.5S revealed the highest effect on rock wettability changes from oil-wet to water-wet conditions in both static and dynamic tests. The formation damage analysis through core-flooding experiments showed that increasing the concentration of sulfate ions twice the sea water causes an 88% reduction in core permeability. However, doubling the magnesium concentration in the presence of sulfate ions reduces the permeability decline to 77%. The maximum recovery factor (i.e., 35%) was attained by injecting SW_1Ca.2 Mg.1.5S into the carbonate core, and core permeability was enhanced twofold. The findings show that simultaneous changes in the concentration of potential-determining ions in smart water, in addition to increasing oil production, also prevent formation damage, which is often neglected in previous studies.

LIU Wei, CAO Xiaopeng, HU Huifang et al.

Significant productivity breakthroughs have been achieved in key production layers of the shale in Jiyang Depression, notably the lower sub-member of the third member and the upper sub-member of the fourth member of Shahejie Formation. Despite these achievements, the development of these layers is relatively recent, and they exhibit considerable variation in individual well production. The primary factors influencing production remain unclear. Currently, a major focus of research is the comprehensive analysis of the main control factors for high production and the selection of reasonable fracturing parameters for shale oil horizontal wells. To better understand the impact of various factors on horizontal well production, factor correlation and pattern analysis are conducted using field data. Techniques such as gray correlation analysis and principal component analysis are employed to quantify the relationships between the average daily oil production over 90, 180, and 270 days and factors like the volume of fracturing fluid used and sand addition. Subsequently, a shale oil productivity prediction model is constructed, and fracturing parameters are optimized using SHAP（SHapley Additive exPlanations）. The research findings suggest that the volume of fracturing fluid, the amount of sand added, and the number of fracture events are the main engineering parameters affecting production. In contrast, geological parameters such as gray matter content, Total Organic Carbon（TOC）, and porosity significantly influence production as well. Over time, the impact of geological factors on production increases, while the influence of engineering factors diminishes during the later stages of production. Optimization analysis of fracturing parameters determined that a stage length of 40~45 meters, a fracturing fluid volume of 2 700 m³, and a sand addition volume of 180 m³ per stage are the optimal settings. These findings offer new insights for development determination and fracturing design in shale oil horizontal wells.

C.E. Obi, A.R. Hasan, M.A. Rahman et al.

This review addresses the diverse applications of multiphase flows, focusing on drilling, completions, and injection activities in the oil and gas industry. Identifying contemporary challenges and suggesting future research directions, it comprehensively reviews evolving applications in these multidisciplinary topics. In drilling, challenges such as gas kicks, cutting transport, and hole cleaning are explored. The application of immersion cooling technology in surface facilities for gas fields utilized in integrated bitcoin mining is also discussed. Nanotechnology, particularly the use of nanoparticles and nanofluids, shows promise in mitigating particulate flow issues and controlling macroscopic fluid behavior. Nanofluids find applications in drilling for formation strengthening and mitigating formation damage in completions as highlighted in this work, as well as in subsurface injection for enhanced oil recovery (EOR), waterflooding, reservoir mapping, and sequestration tracking. The review emphasizes the need for techno-economic analyses using multiphase flow models, particularly in scenarios involving fluid injection for energy storage. Addressing these multiphase flow challenges is crucial for the future of energy diversity and transition initiatives, offering benefits such as financial stability, resilience, sustainability, and reliable supply chains. The first part of this review presents the application of multiphase (typical gas, liquid, solid) flow models and technology for drilling, completion, and injection operations. While the second part reviews the applications of multiphase particulate (nanofluid) flow technology, the use of computational fluid dynamics (CFD), machine learning (ML), and system modeling for multiphase flow models in drilling, completions, and injection operations.

Guoxin LI, Bin ZHANG, Kunyu WU et al.

The geochemical analysis and experimental simulation are comprehensively used to systematically study the hydrocarbon generation material, organic matter enrichment and hydrocarbon generation model of Paleogene source rock in the Western Qaidam Depression, Qaidam Basin, NW China. Three main factors result in low TOC values of saline lacustrine source rock of the Qaidam Basin: relatively poor nutrient supply inhibits the algal bloom, too fast deposition rate causes the dilution of organic matter, and high organic matter conversion efficiency causes the low residual organic carbon. For this type of hydrogen-rich organic matter, due to the reduction of organic carbon during hydrocarbon generation, TOC needs to be restored based on maturity before evaluating organic matter abundance. The hydrocarbon generation of saline lacustrine source rocks of the Qaidam Basin is from two parts: soluble organic matter and insoluble organic matter. The soluble organic matter is inherited from organisms and preserved in saline lacustrine basins. It generates hydrocarbons during low-maturity stage, and the formed hydrocarbons are rich in complex compounds such as NOS, and undergo secondary cracking to form light components in the later stage; the hydrocarbon generation model of insoluble organic matter conforms to the traditional “Tissot” model, with an oil generation peak corresponding to Ro of 1.0%.

WANG Dianlin, YANG Qiong, WEI Bing et al.

The stability of foam system is very important in the application of foam flooding and gas reservoir foam drainage agent. The influence of surfactant molecular structure and interface arrangement on the permeability and stability of foam liquid film is of great significance for the construction of highly stable CO₂ foam, but there is no systematic understanding at present. The betaine surfactant with four molecular structures is used as the research object, and the foam phase property evaluation is used as the research method. For the saturated adsorption capacity, foam liquid film permeability, foam stability and other phase properties, the surfactant molecular structure, interface arrangement, CO₂ foam liquid film permeability, foam stability and their correlation experiments are carried out. The results show that when the molecular head groups of surfactants are consistent, the hydrophobic carbon chain length increases, the hydrophobic effect increases, the molecules on the liquid film surface are arranged more closely, the permeability of foam liquid film decreases, and the stability of foam increases. When surfactant molecules have longer hydrophobic carbon chains, the enhanced hydrophobicity leads to a tighter arrangement of the liquid membrane and an increase in adsorption capacity, hindering the permeation behavior of CO₂ gas within the bubble and weakening the foaming ability of the foaming solution. Based on the regression analysis of the parameters obtained from four foaming systems, the correlation coefficient <i>R</i>² between foam life, foam liquid film molecular adsorption capacity and foaming capacity and foam liquid film permeability <i>K</i> is established. The fitting shows that <i>R</i>²&gt;0.90. Therefore, the permeability of foam liquid film <i>K</i> can be used as one of the parameters to evaluate the stability of foam system and provide a reliable evaluation parameter for the screening of highly stable foam system.

Cheng Yuxiong, Wu Guang'ai, Wu Shiyun et al.

Soluble bridge plugs are deficient for low compressive strength,slow degradation rate,and inapplicability to ultra-high temperature environment.For these problems,an innovative design of all-metal bridge plug for ultra-high temperature environments was proposed.The room-temperature and high-temperature mechanical performance and high-temperature dissolution performance of soluble magnesium-based alloys were performed.Moreover,the materials for key bridge plug components were optimized through the finite element analysis.Finally,the prototype of all-metal bridge plug for ultra-high temperature environments was trial-manufactured and laboratory-tested.The application performance was verified with respect to pressure-bearing and dissolution capacities at room and high temperatures.The results show that with increasing temperature,high-strength soluble magnesium-based alloys present smaller reductions of tensile and yield strengths and yet considerable growth of the elongation rate,compared with high-elongation soluble magnesium-based alloys.At ultra-high temperatures,the dissolution rate of soluble magnesium-based alloys is found with a trend featuring slow-fast-slow variation,and the dissolution rate is the highest at 48～72 hours of dissolution.The developed all-metal bridge plug for ultra-high temperature environments can withstand a pressure difference of up to 70 MPa in 2% KCl aqueous solutions at 205 ℃,and maintain an effective seal for 10 hours.It can be completely dissolved in a closed container under simulated working conditions within 8 days,which meets the design and downhole service requirements.This study provides vital technical support for the development of all-metal bridge plugs suitable for ultra-high temperature environments.

赵月1,2,3，胡晓倩1，任健1,2,3，孙洋1,2,3 ZHAO Yue1,2,3, HU Xiaoqian1, REN Jian1,2,3, SUN Yang1,2,3

为提升粮食加工副产物玉米胚芽的综合利用价值，以玉米胚芽为原料，以出油率为指标，通过单因素试验和正交试验对玉米油的酶法辅助低温压榨法制取工艺条件进行优化，并对最优条件下制取的玉米油基本理化指标进行分析。结果表明：酶法辅助低温压榨法制取玉米油的最优工艺条件为酶解水分含量12%、纤维素酶添加量0.5%、碱性蛋白酶添加量1.0%、酶解温度45 ℃、酶解时间6 h、压榨温度60 ℃、压榨压力50 MPa、压榨时间60 min，在此条件下玉米胚芽的出油率为4189%，较常规低温压榨的出油率（39.68%)高；所制得的玉米油澄清、透明，呈棕红色，理化指标基本符合三级成品玉米油国家标准。综上，酶法辅助低温压榨工艺可获得品质良好的玉米油，同时出油率较常规低温压榨法有所提高。In order to improve the comprehensive utilization value of corn germ as a by-product of grain processing, the extraction conditions of corn oil by enzyme-assisted cold-pressing method were optimized by single factor test and orthogonal test with corn germ as raw material and oil yield as index, and the basic physicochemical indexes of corn oil prepared under the optimal conditions were analyzed. The results showed that the optimal conditions for extracting corn oil by enzyme-assisted cold-pressing method were as follows: enzymatic hydrolysis water content 12%, cellulase dosage 0.5%, alkaline protease dosage 10%, enzymatic hydrolysis temperature 45 ℃,enzymatic hydrolysis time 6 h, pressing temperature 60 ℃, pressing pressure 50 MPa, and pressing time 60 min. Under these conditions, the oil yield was 41.89%, which was higher than that of conventional cold-pressing method (39.68%). The corn oil produced was clear, transparent and brown-red, and its physicochemical indexes basically met the national standard of third grade corn oil. In general, the enzyme-assisted cold-pressing method can obtain corn oil with good quality, and its oil yield is higher than that of conventional cold-pressing method.

Y. Reda, H.M. Yehia, A.M. El-Shamy

Since aluminum is used in many essential applications, it has become a focus of researchers, mainly aluminum alloy 7075, because of its importance in the aircraft industry. The alloy 7075 incorporates high-strength materials such as Al-Cu-Mg, but with Zn through the primary alloy ingredient, instead of copper. Variations in the properties achieved in heat handling of Al-Zn-Mg ingredient 7075 are caused by solution and hardening process precipitation. The word heat-treatment solution means heat-treatment of a metallic structure to remove precipitated particles in the matrix. This work aims at studying the effect of solution treatment, the aging process, and the retrogression process on the mechanical properties of the Al 7075. Test measurements were taken by heating to 470 °C, intended for 30 min, then water quenching from goods, machines, and solutions. For example, not numerous of these collections were aged at R.T. Across 120 h. Other participants aged 24 h at 120 °C artificially. Then the retrogressed for 35 min at 180 °C; the group of these samplings was typically aged in R.T. across 120 h. Other groups were chemically aged for one day at 120 °C and retrogressed for 8 min at 200 °C, and all these samples were naturally aged at the average temperature for 120 h. Many classes were aged chemically for one day at 120 °C. Materials were evaluated by studying their microstructure, hardness, and tensile strength. It has been concluded that the best heat treatment values are the condition (1), indicating that the triple artificial aging gives the highest values of Hardness 49.4 HB and UTS 690 MPa, which were seen and convinced with the microstructure taken for each specimen.

黄传阳1，魏学鼎1，高盼1,2，罗质1,2，胡传荣1,2，何东平1,2 HUANG Chuanyang1, WEI Xueding1, GAO Pan1,2, LUO Zhi1,2, HU Chuanrong1,2, HE Dongping1,2

以黑芝麻为原料，乙醇为提取溶剂，采用超声辅助提取法提取芝麻素。通过单因素试验考察了乙醇体积分数、料液比、超声功率、提取温度及提取时间对芝麻素提取率的影响，并通过响应面法优化了芝麻素的提取工艺条件。结果表明：超声辅助提取芝麻素的最佳工艺条件为乙醇体积分数60%、料液比1∶ 15、超声功率300 W、提取温度57.0 ℃、提取时间2.3 h，在最佳工艺条件下芝麻素提取率为0.449 6%。研究结果为芝麻素的开发及利用提供了理论依据。 Sesamin was extracted from black sesame by ultrasound-assisted extraction method with ethanol as extraction solvent. The effects of ethanol volume fraction, solid-liquid ratio, ultrasonic power, extraction temperature and extraction time on the extraction rate of sesamin were studied by single factor experiment. The extraction process of sesamin was optimized by response surface methodology. The results showed that the optimal conditions were obtained as follows: ethanol volume fraction 60%, solid-liquid ratio 1∶ 15, ultrasonic power 300 W, extraction temperature 57.0 ℃ and extraction time 23 h. Under the optimal conditions, the extraction rate of sesamin was 0.449 6%. The study provided guidance for the development and utilization of sesamin.

Aniefiok Sylvester Akpan, Francisca Nneka Okeke, Daniel Nnaemeka Obiora et al.

Abstract 3D seismic volume and two well logs data labelled Bonna-6 and Bonna-8 were employed in the inversion process. The data set was simultaneously inverted to produce P- and S-impedances, density, V P  −  V S , and PI seismic attributes. An average “c” term value of 1.37 was obtained from the inverse of the slope of the crossplot of P-impedance versus S-impedance for Bonna-6 and Bonna-8 wells. This value was employed in the inversion process to generate the PI attribute, which aided in reducing the non-uniqueness inherent in discriminating the probable reservoir sands. Five seismic attributes slices were generated to ascertain the superiority of each attribute in delineating the probable reservoir sand. These attributes were: density, S-impedance, P-impedance, V P − V S ratio and PI. These attributes reveal low value of density (1.96 − 2.14 g/cc), P-impedance (1.8 × 104 − 2.1 × 104) ft/s*g/cc, S-impedance (9.2 × 103 − 1.1 × 104) ft/s*g/cc, V P  − V S (1.65 − 1.72) and PI (4.9 × 103 − 5.1 × 104) ft/s*g/cc around the area inferred to be hydrocarbon saturated reservoir. Although the attributes considered reveals the same zone suspected to be probable hydrocarbon zone, PI gives a better discrimination when compared to other attributes. A distinctive spread and demarcation of the delineated hydrocarbon sand are observed in the PI attribute slice.

Biyuan SHUI

To further increase the knowledge and understanding of the pipeline industry to its intelligent development, the status and trend of intelligent industry at home and abroad were investigated and analyzed, the relevant applicationcases of intelligent pipeline abroad were collected, and the results of work carried out in the construction of intelligentpipeline network in China and the practice of intelligent pipeline engineering in China-Russia Eastern Gas Pipeline weresummarized. The construction of intelligent industry (including the intelligent pipeline network) at home and abroad isgenerally in the primary stage of development, of which the development direction focused on the Internet of Things, digitaltwins, robots, intelligent equipment diagnosis, industrial internet platform application and so on. At the same time, the overallideas of data unification, system integration and standardization development were proposed. On this basis, the overallsolution of intelligent pipeline network with comprehensive systems and engineering operability was proposed. The overallstructure of intelligent pipeline network was established based on the aspects of business, intelligence and capability, andthe specific contents of each aspect were clarified. Besides, the result-oriented basic model for capability maturity evaluationof intelligent pipeline network was also proposed. On the principle of "from simple to difficult, from point to surface, andfrom part to whole", the developing route of "automatization, intellectualization and platformization" was put forward to theintelligent pipeline network. Finally, the problems existing in the construction of intelligent pipeline network were analyzedin depth, and the targeted development strategy was put forward.

Saeed Shad, Abouzar Daneshpajouh

Understanding and modeling of three-phase transient flow in gas-condensate wells play a vital role in designing and optimizing dynamic kill procedure of each well that needs to capture the discontinuities in density, geometry, and velocity of phases but also the effect of temperature on such parameters. In this study, two-phase Advection-Upstream-Splitting-Method (AUSMV) hybrid scheme is extended to a three-phase model capable of modeling blowout and dynamic kill in gas-condensate-water wells. In order to better understand and model such a process, density and viscosity changes are calculated using the Peng-Robinson equation of state. Moreover, the resulted simulator enables us to study and model highly changing flow conditions during blowout and dynamic kill process applied to a well in a gas condensate reservoir. In addition, a sensitivity analysis has been conducted on the relief well kill rate, pump step down schedule, and well intersection depth. Moreover, the results reveal the impact and influence of each of these parameters on dynamic kill process. Finally, the model introduced here and the results of the sensitivity analysis using this transient three-phase model can be used to better design a control process for wells in gas condensate reservoirs.

Han Jingjing, Hou Guangdong, Jing Zhiming

To prevent the accidents of kick, blowout and tubing jack during tubing string tripping in workover operation, the remote control hydraulic anti-jack and anti-blowout device has been developed. The device, using hydraulic plug-in plugging technology, could both quickly plug tubing and switch channels within the tubing to ensure the well killing needs. The whole set of device, which is remotely hydraulic controlled, could achieve mechanical automatic control when the tubing jacksand the overflow occurs,and reduced labor intensity feature without personnel operation on the wellhead. During the simulation of the overflow in the tubing,alignment, plug-in and plugging the tubing was completed in 34 seconds. The automatic control and remote control of the device contribute to the safe production, environmental protection and labor intensity reduction.

Lichen ZHENG, Jiaqing YU, Qinghai YANG et al.

To overcome the disadvantages of traditional downhole communication methods, a vibration wave downhole communication technique is proposed, and a vibration wave downhole communication system is developed. This technique has been verified by field test and is applied to separated layer water injection. It is shown by theoretical and test research that transmission of the vibration wave through tubing and casing appears as the alternate distribution of pass-band and stop-band. According to that, a multi-baseband transmission strategy is formulated. The on-off keying modulation and Manchester encoding scheme are used to load the control information into the vibration wave. A generation system of vibration signals is developed to realize the controllable conversion from electric energy into vibration wave energy. A receiving and decoding system of vibration waves, which uses a micro-vibration acceleration sensor as the signal pickup element, is developed too. A test system for vibration wave downhole remote transmission is designed and applied to field test. The feasibility of the technique and the accuracy and reliability of communication system are verified and the attenuation characteristics of casing vibration wave signals are obtained. This technique has been applied to separated layer water injection successfully with wide application prospect in wellbore control field. Key words: vibration wave, downhole communication, on-off-keying modulation, Manchester encoding, magne-tostrictive material, micro-vibration acceleration sensor

Fan Mingtao, Liu Gonghui, Li Jun et al.

Some shale gas wells in Sichuan have experienced casing deformation under large displacement multistage fracturing operation, which has seriously influenced the shale gas wells regular production.To address the issue, a casing-cement sheath-formation stress finite element analysis model under heat-mechanical coupling condition has been established with ABAQUS software to simulate stress distribution of casing and temperature distribution of the system during fracturing.With this model, under different injection fluids temperatures, the effects of casing eccentricity and cement sheath defectiveness on the casing stress has been analyzed.The results show that, in the fracturing process with high displacement, the eccentricity of casing will result in a decline of the casing stress, and the temperature decline have a great influence on casing stress.The casing stress increases with the increase of the cement sheath circumferential discontinuity under different injection fluid temperature.The influence of fluid temperature on the casing stress showed a trend of increase after down first.The influence of the missing location and the depth of the cement sheath on the casing stress are small.The injection fluid temperature is the main casing stress control factor.With the eccentricity of the casing, the combined effects of the temperature decline and the missing of cement sheath would result in greatly increased casing stress.The study method and results could provide theoretical supports for shale gas development in the future.

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<span style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体">涡轮钻具轴承组在恶劣的工作环境中受到钻压、水力载荷以及钻进冲击与振动的作用，容易发生磨损现象，直接影响涡轮钻具的使用寿命。以φ127 mm涡轮钻具为例，根据弹塑性力学和赫兹接触理论，运用ABAQUS软件建立定子－滚珠－转子非线性接触问题有限元模型，针对不同磨损程度的滚珠轴承进行了数值模拟分析。研究结果表明，随磨损量的增大，轴承定子、转子与滚珠的接触面积逐渐减小，应力集中现象加剧，接触应力明显增大；最大接触应力出现在滚珠上，且与磨损量呈现非线性关系；相同工况下，磨损2 mm后滚珠的最大Mises应力比未磨损时增加了14倍，轴承发生失效。该项研究成果对涡轮钻具设计及寿命预测具有指导作用。</span>