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Expert Experience and Data-Driven Based Hybrid Fault Diagnosis for High-SpeedWire Rod Finishing Mills 被引量:1
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作者 Cunsong Wang Ningze Tang +3 位作者 Quanling Zhang Lixin Gao Haichen Yin Hao Peng 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1827-1847,共21页
The reliable operation of high-speed wire rod finishing mills is crucial in the steel production enterprise.As complex system-level equipment,it is difficult for high-speed wire rod finishing mills to realize fault lo... The reliable operation of high-speed wire rod finishing mills is crucial in the steel production enterprise.As complex system-level equipment,it is difficult for high-speed wire rod finishing mills to realize fault location and real-time monitoring.To solve the above problems,an expert experience and data-driven-based hybrid fault diagnosis method for high-speed wire rod finishing mills is proposed in this paper.First,based on its mechanical structure,time and frequency domain analysis are improved in fault feature extraction.The approach of combining virtual value,peak value with kurtosis value index,is adopted in time domain analysis.Speed adjustment and side frequency analysis are proposed in frequency domain analysis to obtain accurate component characteristic frequency and its corresponding sideband.Then,according to time and frequency domain characteristics,fault location based on expert experience is proposed to get an accurate fault result.Finally,the proposed method is implemented in the equipment intelligent diagnosis system.By taking an equipment fault on site,for example,the effectiveness of the proposed method is illustrated in the system. 展开更多
关键词 High-speed wire rod finishing mills expert experience DATA-DRIVEN fault diagnosis
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Sealing capacity evaluation of underground gas storage under intricate geological conditions 被引量:1
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作者 Guangquan Zhang Sinan Zhu +4 位作者 Daqian Zeng Yuewei Jia Lidong Mi Xiaosong Yang Junfa Zhang 《Energy Geoscience》 EI 2024年第3期234-243,共10页
Evaluating underground gas storage(UGS)sealing capacity is essential for its safe construction and operational efficiency.This involves evaluating both the static sealing capacity of traps during hydrocarbon accumulat... Evaluating underground gas storage(UGS)sealing capacity is essential for its safe construction and operational efficiency.This involves evaluating both the static sealing capacity of traps during hydrocarbon accumulation and the dynamic sealing capacity of UGS under intensive gas injection and withdrawal,and alternating loads.This study detailed the methodology developed by Sinopec.The approach merges disciplines like geology,geomechanics,and hydrodynamics,employing both dynamic-static and qualitative-quantitative analyses.Sinopec's evaluation methods,grounded in the in situ stress analysis,include mechanistic studies,laboratory tests,geological surveys,stress analysis,and fluid-solid interactions.Through tests on the static and dynamic sealing capacity of UGS,alongside investigations into sealing mechanisms and the geological and geomechanical properties of cap rocks and faults,A geomechanics-rock damage-seepage mechanics dynamic coupling analysis method has been developed to predict in situ stress variations relative to pore pressure changes during UGS operations and evaluate fault sealing capacity and cap rock integrity,thereby setting the maximum operational pressures.Utilizing this evaluation technique,Sinopec has defined performance metrics and criteria for evaluating the sealing capacity of depleted gas reservoirs,enabling preliminary sealing capacity evaluations at UGS sites.These evaluations have significantly informed the design of UGS construction schemes and the evaluation of fault sealing capacity and cap rock integrity during UGS operations. 展开更多
关键词 Underground gas storage sealing capacity GEOMECHANICS Maximum operational pressure
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Interfacial friction effects on sealing performances of elastomer packer
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作者 Peng-Cheng Wang Ming-Hui Chen +2 位作者 Jim Jenkinson Yong-Xin Song Li Sun 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期2037-2047,共11页
Elastomer sealing performance is of critical importance for downhole tools application including the use of fracturing(Frac)plugs during multi-stage hydraulic fracking.In practice sealing performances of such plugs ar... Elastomer sealing performance is of critical importance for downhole tools application including the use of fracturing(Frac)plugs during multi-stage hydraulic fracking.In practice sealing performances of such plugs are normally evaluated through pressure tests,and in numerical simulation studies,maximum contact stress,average contact stress and contact length data are used to determine sealing quality between a packer and casing.In previous studies,the impact of friction forces on sealing performance is often overlooked.This work aims to fill this knowledge gap in determining the influence of friction forces on elastomer packer sealing performances.We first determined the most appropriate constitutive hyperelastic model for the elastomers used in frac plug.Then we compared analytical calculation results with Finite Element Analysis simulation using a simplified tubular geometry and showed the significant influences on interfacial friction on elastomer packer stress distribution,deformation,and contact stress after setting.With the demonstration of validity of FEA method,we conducted systematic numerical simulation studies to show how the interfacial friction coefficients can affect the maximum contact stress,average contact stress,contact stress distribution,and maximum mises stress for an actual packer used in plug products.In addition,we also demonstrated how the groove in a packer can affect packer deformation and evolvement during setting with the consideration of interfacial stress.This study underscores the critical role that friction forces play in Frac plug performance and provides a new dimension for optimizing packer design by controlling interfacial interactions at the packer contact surfaces. 展开更多
关键词 Elastomer seal FRICTION sealing performance Contact stress
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Synthesis and Characterization of Nonionic Waterborne Polyurethane and Application to Wool Fabric Finishing
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作者 殷映婷 FENG Mao +1 位作者 姚金波 牛家嵘 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期497-505,共9页
A nonionic waterborne polyurethane(WPU) was synthesized by the self-emulsification method using polyether diol(N220),isophorone diisocyanate(IPDI),trimethylolpropane poly(ethylene glycol monomethyl ether)(N120),1,4-bu... A nonionic waterborne polyurethane(WPU) was synthesized by the self-emulsification method using polyether diol(N220),isophorone diisocyanate(IPDI),trimethylolpropane poly(ethylene glycol monomethyl ether)(N120),1,4-butanediol(BDO) and trimethylolpropane(TMP) as the main materials.The effects of the NCO/OH ratio on the emulsion and film properties of NWPU were explored.The experimental results show that the NWPU prepared at an NCO/OH ratio of 1.1 has good emulsion stability and easy film formation,and the resultant film was elastic,soft,and transparent.The sample was used for wool finishing and the application performance was evaluated.When the NWPU dosage reached 40 g·L^(-1),the fabric area felt shrinkage rate reduced from 8.97% to 4.75%,the pilling rating raised from grade 2-3 to grade 4,and the whiteness value only decreased by 3.87%. 展开更多
关键词 waterborne polyurethane NONIONIC wool finishing ANTI-PILLING anti-shrinking
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Evolution and Application of Sealing Ability of Gypsum Caprocks under Temperature-Pressure Coupling:An Example of the ZS5 Well in the Tazhong Area of the Tarim Basin
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作者 LIU Hua ZHAO Shan +3 位作者 YANG Xianzhang ZHU Yongfeng WANG Shen ZHANG Ke 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期168-184,共17页
Gypsum caprocks'sealing ability is affected by temperature-pressure coupling.Due to the limitations of experimental conditions,there is still a lack of triaxial stress-strain experiments that simultaneously consid... Gypsum caprocks'sealing ability is affected by temperature-pressure coupling.Due to the limitations of experimental conditions,there is still a lack of triaxial stress-strain experiments that simultaneously consider changes in temperature and pressure conditions,which limits the accuracy of the comprehensive evaluation of the brittle plastic evolution and sealing ability of gypsum rocks using temperature pressure coupling.Triaxial stress-strain tests were utilized to investigate the differences in the evolution of the confinement capacity of gypsum rocks under coupled temperaturepressure action and isothermal-variable pressure action on the basis of sample feasibility analysis.According to research,the gypsum rock's peak and residual strengths decrease under simultaneous increases in temperature and pressure over isothermal pressurization experimental conditions,and it becomes more ductile.This reduces the amount of time it takes for the rock to transition from brittle to plastic.When temperature is taken into account,both the brittle–plastic transformation's depth limit and the lithological transformation of gypsum rocks become shallower,and the evolution of gypsum rocks under variable temperature and pressure conditions is more complicated than that under isothermal pressurization.The sealing ability under the temperature-pressure coupling is more in line with the actual geological context when the application results of the Well#ZS5 are compared.This provides a theoretical basis for precisely determining the process of hydrocarbon accumulation and explains why the early hydrocarbon were not well preserved. 展开更多
关键词 temperature-pressure coupling gypsum caprocks brittle-plastic evolution sealing capacity Tarim Basin
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Fracture sealing performance of granular lost circulation materials at elevated temperature:A theoretical and coupled CFD-DEM simulation study
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作者 Chong Lin Qi-Cong Xu +4 位作者 Lie-Xiang Han Gao Li Hai He Hong-Ling Zhou Ji-Ping She 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期567-581,共15页
Lost circulation is a common downhole problem of drilling in geothermal and high-temperature,high-pressure(HTHP)formations.Lost circulation material(LCM)is a regular preventive and remedial measure for lost circulatio... Lost circulation is a common downhole problem of drilling in geothermal and high-temperature,high-pressure(HTHP)formations.Lost circulation material(LCM)is a regular preventive and remedial measure for lost circulation.However,conventional LCMs seem ineffective in high-temperature formations.This may be due to the changes in the mechanical properties of LCMs and their sealing performance under high-temperature conditions.To understand how high temperature affects the fracture sealing performance of LCMs,we developed a coupled computational fluid dynamics-discrete element method(CFD-DEM)model to simulate the behavior of granular LCMs in fractures.We summarized the literature on the effects of high temperature on the mechanical properties of LCMs and the rheological properties of drilling fluid.We conducted sensitivity analyses to investigate how changing LCM slurry properties affected the fracture sealing efficiency at increasing temperatures.The results show that high temperature reduces the size,strength,and friction coefficient of LCMs as well as the drilling fluid viscosity.Smaller,softer,and less frictional LCM particles have lower bridging probability and slower bridging initiation.Smaller particles tend to form dual-particle bridges rather than single-particle bridges.These result in a deeper,tighter,but unstable sealing zone.Reduced drilling fluid viscosity leads to faster and shallower sealing zones. 展开更多
关键词 Geothermal well drilling HTHP formationLost circulation material CFD-DEM Fracture sealing
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Dynamic evaluation on sealing capacity of caprocks of the Meso-Neoproterozoic reservoirs in Ordos Basin,China
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作者 Yusong Yuan Yunqin Hao Rongqiang Zhang 《Energy Geoscience》 EI 2024年第1期99-107,共9页
The Meso-Neoproterozoic is a new play in the Ordos Basin.A deeper understanding about the dynamic relationship between the caprocks and the source rocks is needed.Based on the comprehensive analysis of hydrocarbon sou... The Meso-Neoproterozoic is a new play in the Ordos Basin.A deeper understanding about the dynamic relationship between the caprocks and the source rocks is needed.Based on the comprehensive analysis of hydrocarbon source development characteristics of the Meso-Neoproterozoic and its overlying strata,as well as the formation contact relationships,lithology characteristics and exploratory drilling data,it is recognized that the Meso-Neoproterozoic contains two types of petroleum accumulation assemblage,that is,the“self-sourced indigenous”and“upper source rock-lower reservoir”assemblages.The former is mainly controlled by the development and distribution of source rocks of the Changcheng System,with the Lower Cambrian shale sequence as its caprock.The later is controlled by the superposition between the Meso-Neoproterozoic and its overlying source rocks and this assemblage is mainly distributed in Hangjinqi and Pingliang areas with the Carboniferous-Permian shale sequence as its caprock.The dynamic evaluation on the displacement pressure serves to reconstruct the displacement pressure history of the caprock.The results show that the shale sequence of the Cambrian Maozhuang Formation in well XY 1 in the southern Ordos Basin has possibly acquired the ability of sealing natural gas since the early of Late Triassic.Its displacement pressure increased rapidly up to 20 MPa during the Late Triassic-Jurassic and keeps at 9.2 MPa at present,indicating fair sealing ability.The Carboniferous-Permian caprocks in Hangjinqi area could have acquired the ability to seal natural gas in the Late Jurassic-Early Cretaceous,and the present-day displacement pressure is 9e12 MPa,indicating good sealing ability.The upper Paleozoic caprock in Pingliang area has been able to seal natural gas since the Early Jurassic,with a maximum displacement pressure of 23 MPa during the Cretaceous period and a current value of 17 e20 MPa,indicative of strong ability to seal natural gas.The sealing ability of caprocks of both the“selfsourced indigenous”and“upper source rock-lower reservoir”assemblages has come into being earlier than or at least no later than the peak gas generation of the source rocks and therefore the caprocks are dynamically effective in geohistory.The Meso-Neoproterozoic reservoirs in the Ordos Basin are well preserved and probabally of better potential for exploration in terms of the caprock-source rock combination. 展开更多
关键词 Ordos Basin MESO-NEOPROTEROZOIC Caprock sealing ability Displacement pressure
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Evaluation of the dynamic sealing performance of cap rocks of underground gas storage under multi-cycle alternating loads
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作者 Lidong Mi Yandong Guo +3 位作者 Yanfeng Li Daqian Zeng Chunhua Lu Guangquan Zhang 《Energy Geoscience》 EI 2024年第4期125-132,共8页
The static sealing of underground gas storage(UGS),including the integrity of cap rocks and the stability of faults,is analyzed from a macro perspective using a comprehensive geological evaluation method.Changes in po... The static sealing of underground gas storage(UGS),including the integrity of cap rocks and the stability of faults,is analyzed from a macro perspective using a comprehensive geological evaluation method.Changes in pore structure,permeability,and mechanical strength of cap rocks under cyclic loads may impact the rock sealing integrity during the injection and recovery phases of UGS.In this work,the mechanical deformation and failure tests of rocks,as well as rock damage tests under alternating loads,are conducted to analyze the changes in the strength and permeability of rocks under multiple-cycle intense injection and recovery of UGS.Additionally,this study proposes an evaluation method for the dynamic sealing performance of UGS cap rocks under multi-cycle alternating loads.The findings suggest that the failure strength(70%)can be used as the critical value for rock failure,thus providing theoretical support for determining the upper limit of operating pressure and the number of injection-recovery cycles for the safe operation of a UGS system. 展开更多
关键词 Alternating load Cap rock Dynamic sealing performance Underground gas storage
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High-Speed and Low-Noise Gear Finishing by Gear Grinding and Honing:A Review
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作者 Xiaoqing Tian Yukai Sun +2 位作者 Weihao Mu Lian Xia Jiang Han 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第5期19-39,共21页
Gears are important mechanical parts for transmitting power and play an increasingly important role in the machinery industry.The electric vehicle industry developed rapidly and became a vital development field of the... Gears are important mechanical parts for transmitting power and play an increasingly important role in the machinery industry.The electric vehicle industry developed rapidly and became a vital development field of the automotive industry over the past few years.The conversion of energy increases the requirements for electric vehicle transmissions,which promotes the development of high-speed and low-noise transmission gear.This paper elaborates on the research progress of high-speed and low-noise gear finishing methods.Firstly,this review analyses the machining requirements,finishing,and specific machining technologies of high-speed and low-noise gears.The importance of gear grinding and honing in high-speed and low-noise gear machining is highlighted.Secondly,the applications of gear grinding and honing in gear modification,error compensation,and texture control are analyzed.Furthermore,the role of precision machining technology in improving gear performance is clarified.Finally,the design and processing methods of the modified tooth flank for gear modification are summarized.In addition,the influence of tooth surface texture on noise is described,and the texture change methods are explored.The well-known open problems of gear finishing are finally identified,and some new research interests are also pointed out.This review will provide valuable references for further research on gear finishing. 展开更多
关键词 High-speed and low-noise gear Gear machining technology Gear finishing Tooth flank modification Tooth surface texture
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Textile industry innovations in dyeing and finishing processes:Minimizing environmental impact
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《China Textile》 2024年第4期43-47,共5页
Textiles are one of the oldest industries in the world which has been manufacturing fabrics and materials needed for various purposes.However,the industry has been confronted with some problems regarding its pollution... Textiles are one of the oldest industries in the world which has been manufacturing fabrics and materials needed for various purposes.However,the industry has been confronted with some problems regarding its pollution;specifically the dyeing and finishing processes.As for the given issues,there has been a trend in recent years to come up with more environmentally friendly solutions. 展开更多
关键词 finishing DYEING IMPACT
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Finishing first with Monforts at Techtextil 2024
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《China Textile》 2024年第2期46-47,共2页
Monforts–which celebrates its 140th anniversary this year–continues to lead the field in finishing and coating technologies for technical textiles.The company is looking forward to many fruitful discussions on the s... Monforts–which celebrates its 140th anniversary this year–continues to lead the field in finishing and coating technologies for technical textiles.The company is looking forward to many fruitful discussions on the scope of existing and new processes and applications at the forthcoming Techtextil show in Frankfurt from April 23-26. 展开更多
关键词 COATING finishing discussions
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Study on Sealing Characteristics of Sliding Seal Assembly of Aircraft Hydraulic Actuator
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作者 Weinan Li Saixin Shi +4 位作者 Hongxia Tang Liang Chen Jiawei Zhang Hao Tang Jianhua Zhao 《Instrumentation》 2024年第1期18-29,共12页
The hydraulic actuator,known as the"muscle"of military aircraft,is responsible for flight attitude adjustment,trajectory control,braking turn,landing gear retracting and other actions,which directly affect i... The hydraulic actuator,known as the"muscle"of military aircraft,is responsible for flight attitude adjustment,trajectory control,braking turn,landing gear retracting and other actions,which directly affect its flight efficiency and safety.However,the sealing assembly often has the situation of over-aberrant aperture fit clearance or critical over-aberrant clearance,which increases the failure probability and degree of movable seal failure,and directly affects the flight efficiency and safety of military aircraft.In this paper,the simulation model of hydraulic actuator seal combination is established by ANSYS software,and the sealing principle is described.The change curve of contact width and contact pressure of combination seal under the action of high-pressure fluid is drawn.The effects of different oil pressure,fit clearance and other parameters on the sealing performance are analyzed.Finally,the accelerated life test of sliding seal components is carried out on the hydraulic actuator accelerated life test rig,and the surface morphology is compared and analyzed.The research shows that the O-ring is the main sealing element and the role of the check ring is to protect and support the O-ring to prevent damage caused by squeezing into the fit clearance,so the check ring bears a large load and is prone to shear failure.Excessive fit clearance is the main factor affecting the damage of the check ring,and the damage parts are mainly concentrated at the edge of the sealing surface.This paper provides a theoretical basis for the design of hydraulic actuator and the improvement of sealing performance. 展开更多
关键词 hydraulic actuator contact stress sealing characteristics maximum shear stress
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Fracture sealing based on microbially induced carbonate precipitation and its engineering applications:A review
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作者 Zhichao Song Chuangzhou Wu +1 位作者 Zuoyong Li Danyi Shen 《Biogeotechnics》 2024年第4期41-51,共11页
In this review,the development and application of microbially induced carbonate precipitation(MICP)technology for the sealing of underground engineering fractures are discussed in detail.The importance of sealing micr... In this review,the development and application of microbially induced carbonate precipitation(MICP)technology for the sealing of underground engineering fractures are discussed in detail.The importance of sealing micro-fractures in an environmentally friendly and efficient manner is emphasized,and the potential of the MICP method in controlling pore and fracture seepage is highlighted.The fundamental mechanisms,key influencing factors,numerical models,and applications of the MICP in the fields of geological CO_(2) storage and oil resources development are comprehensively summarized in the paper.At the same time,the limitations of the existing research and the future research directions are discussed,especially in terms of improving the processing efficiency,environmental impacts,and cost considerations.Overall,the development of MICP technology provides a new environmentally friendly reinforcement method for geotechnical engineering and is expected to play a key role in the future development of underground space engineering. 展开更多
关键词 Microbially induced carbonate precipitation(MICP) Fracture sealing Bio-grouting Engineering applications
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中药丸剂塑料球壳外层密封专用蜡的研究开发
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作者 吴国江 夏树斌 刘青竹 《石油炼制与化工》 CAS 北大核心 2025年第1期167-171,共5页
研制了一种用于中药丸剂塑料球壳外层密封的专用蜡。将54号全炼石蜡和80号软质微晶蜡的混合物作为基础蜡料,考察各种添加剂对基础蜡料的熔点、运动黏度及其他性能的影响,确定该专用蜡的最佳制备配方为:54号全炼石蜡与80号软质微晶蜡的... 研制了一种用于中药丸剂塑料球壳外层密封的专用蜡。将54号全炼石蜡和80号软质微晶蜡的混合物作为基础蜡料,考察各种添加剂对基础蜡料的熔点、运动黏度及其他性能的影响,确定该专用蜡的最佳制备配方为:54号全炼石蜡与80号软质微晶蜡的质量比为9∶1,低相对分子质量聚乙烯、C 5加氢石油树脂、乙烯-醋酸乙烯酯共聚物(EVA)、黏度调节助剂A、煤基费-托合成软质蜡、非晶态α-烯烃共聚物(APAO)的加入量(w,以基础蜡料的质量计)分别为1.0%,1.0%,0.5%,3.0%,20%,1.5%。在温度为120℃、时间为30 min、搅拌转速为200 r min的条件下制备的密封专用蜡在40℃及-10~-20℃下不变形、不龟裂,性能优于参比样品。 展开更多
关键词 中药丸 塑料球壳 密封蜡 运动黏度
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A STUDY ON THE SEALING PERFORMANCE BETWEEN CYLINDER HEAD AND CYLINDER SLEEVE IN DIESEL ENGINES 被引量:2
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作者 廖日东 左正兴 《兵工学报》 EI CAS CSCD 北大核心 2000年第1期-,共5页
针对12V型整体式气缸盖柴油机的气缸盖/气缸套密封系统,采用有限元法,研究了固紧螺栓预紧力大小及分配、固紧螺栓位置、气缸盖材料等因素对密封系统性能的影响规律。对确定的气缸爆发压力,计算出了理论上能保证密封的最小预紧力。得... 针对12V型整体式气缸盖柴油机的气缸盖/气缸套密封系统,采用有限元法,研究了固紧螺栓预紧力大小及分配、固紧螺栓位置、气缸盖材料等因素对密封系统性能的影响规律。对确定的气缸爆发压力,计算出了理论上能保证密封的最小预紧力。得出的结论有益于对整体式气缸盖柴油机的改进设计。文中计算采用了SDRC公司的I-DEASTM软件。 展开更多
关键词 柴油机 气缸盖 密封 有限元法 A STUDY ON THE sealing PERFORMANCE BETWEEN
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Numerical simulation of two-phase flow field in underwater sealing device based on dynamic mesh 被引量:1
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作者 张学伟 李强 吕梦柔 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第3期253-257,共5页
In order to speed underwater launch of minor-caliber weapons,a sealing device can be set in front of underwater muzzle to separate water,preventing the muzzle from water immersion.By establishing and simplifying the m... In order to speed underwater launch of minor-caliber weapons,a sealing device can be set in front of underwater muzzle to separate water,preventing the muzzle from water immersion.By establishing and simplifying the model of underwater weapon sealing device and unstructured mesh computing domain model based on computational fluid dynamics(CFD),dynamic mesh and user defined function(UDF),the N-S equation is solved and the numerical analysis and calculation of the complex two-phase flow inside the sealing device are carried out.The results show that the gas discharged from the sealing device is conducive to the formation of the projectile supercavity.When the projectile is launched at 5munder water,the shock wave before and after the projectile has impact on the box body up to 100 MPa,therefore the sealing device must be strong enough.The research results have the vital significance to the design of underwater weapon sealing device and the formation of the projectile supercavitation. 展开更多
关键词 two-phase flow SUPERCAVITATION sealing device computational fluid dynamics(CFD) dynamic mech
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Multi-Stage-Based Siamese Neural Network for Seal Image Recognition
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作者 Jianfeng Lu Xiangye Huang +3 位作者 Caijin Li Renlin Xin Shanqing Zhang Mahmoud Emam 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期405-423,共19页
Seal authentication is an important task for verifying the authenticity of stamped seals used in various domains to protect legal documents from tampering and counterfeiting.Stamped seal inspection is commonly audited... Seal authentication is an important task for verifying the authenticity of stamped seals used in various domains to protect legal documents from tampering and counterfeiting.Stamped seal inspection is commonly audited manually to ensure document authenticity.However,manual assessment of seal images is tedious and laborintensive due to human errors,inconsistent placement,and completeness of the seal.Traditional image recognition systems are inadequate enough to identify seal types accurately,necessitating a neural network-based method for seal image recognition.However,neural network-based classification algorithms,such as Residual Networks(ResNet)andVisualGeometryGroup with 16 layers(VGG16)yield suboptimal recognition rates on stamp datasets.Additionally,the fixed training data categories make handling new categories to be a challenging task.This paper proposes amulti-stage seal recognition algorithmbased on Siamese network to overcome these limitations.Firstly,the seal image is pre-processed by applying an image rotation correction module based on Histogram of Oriented Gradients(HOG).Secondly,the similarity between input seal image pairs is measured by utilizing a similarity comparison module based on the Siamese network.Finally,we compare the results with the pre-stored standard seal template images in the database to obtain the seal type.To evaluate the performance of the proposed method,we further create a new seal image dataset that contains two subsets with 210,000 valid labeled pairs in total.The proposed work has a practical significance in industries where automatic seal authentication is essential as in legal,financial,and governmental sectors,where automatic seal recognition can enhance document security and streamline validation processes.Furthermore,the experimental results show that the proposed multi-stage method for seal image recognition outperforms state-of-the-art methods on the two established datasets. 展开更多
关键词 Seal recognition seal authentication document tampering siamese network spatial transformer network similarity comparison network
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建筑电气设备用丙烯酸酯橡胶密封圈失效原因分析
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作者 姜广明 辛朝晖 +3 位作者 王广克 胡水 贾颖华 肖凯巍 《橡胶工业》 CAS 2025年第1期49-52,共4页
拆取建筑电气设备上未发生渗漏失效和发生渗漏失效的2种丙烯酸酯橡胶密封圈,观察失效状态并分析失效原因。红外分析和热重分析表明2种密封圈胶料的组成一致,物理性能分析表明失效密封圈胶料的硬度较低和拉伸性能较差,动态力学性能分析... 拆取建筑电气设备上未发生渗漏失效和发生渗漏失效的2种丙烯酸酯橡胶密封圈,观察失效状态并分析失效原因。红外分析和热重分析表明2种密封圈胶料的组成一致,物理性能分析表明失效密封圈胶料的硬度较低和拉伸性能较差,动态力学性能分析表明失效密封圈胶料的交联密度较低。综合推断,密封圈渗漏可能是由于其硫化程度不够,强度不足,在装配时被挤压变形而破损,加之耐油性能降低,导致失效。 展开更多
关键词 丙烯酸酯橡胶 密封圈 失效 物理性能 动态力学性能 硫化程度
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一种新的转子轴端密封结构设计--阶梯式
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作者 康鹏志 秦恩臣 +1 位作者 刘麒麟 刘冰 《橡塑技术与装备》 CAS 2025年第1期30-33,共4页
本文简要介绍目前密炼机转子常用的几种轴端密封形式及其优缺点,探讨一种新的转子轴端密封结构设计——阶梯式,该结构可以在一定程度上改善密封效果,减少维护更换次数。
关键词 密炼机 轴端密封 接触面 阶梯式
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Metal Sealing Performance of Subsea X-tree Wellhead Connector Sealer 被引量:13
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作者 ZHAO Honglin CHEN Rui +5 位作者 LUO Xiaolan DUAN Menglan LU Yinghui FU Guowei TIAN Hongping YE Daohui 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第3期649-656,共8页
The metal sealing performance of subsea X-tree wellhead connectors is crucial for the safety and reliability of subsea X-trees. In order to establish the theoretical relation between metal sealing ring's contact stre... The metal sealing performance of subsea X-tree wellhead connectors is crucial for the safety and reliability of subsea X-trees. In order to establish the theoretical relation between metal sealing ring's contact stress and its structural parameters and working pressure, a mechanical analysis method for double-cone sealing of high pressure vessels is applied in analyzing the metal sealing ring under the condition of preload and operation. As a result, the formula of the unit sealing load for the metal sealing ring under operation with residual preload is shown in this paper, which ensures that the metal sealing ring has an excellent sealing effect and can prevent the metal sealing ring from yielding. Besides, while analyzing the sealing process of the metal sealing ring, the change rule of contact stress and working pressure is concluded here, putting forward that the structural parameters of the metal sealing ring are the major factors affecting the change rule. Finally, the analytical solution through theoretical analysis is compared with the simulation result through finite element analysis in a force feedback experiment, and both are consistent with each other, which fully verifies for the design and calculation theory on metal sealing ring's contact stress and its structural parameters and working pressure deduced in this paper. The proposed research will be treated as an applicable theory guiding the design of metal seal for subsea X-tree wellhead connectors. 展开更多
关键词 sealing ring metal sealing mechanical analysis subsea X-tree wellhead connector subsea X-tree
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