深水采油树Spring-Seal密封圈接触模型构建与实验测试

为提高深水采油树在高压、高温、低温等工况下长时间工作的稳定性,对采油树密封圈进行重新设计,提出Spring-Seal密封圈(以下简称S密封圈);基于赫兹接触理论、填料密封接触理论,重新构建S密封圈接触力学模型;建立有限元仿真分析模型,分析不同条件下S密封圈的密封性能,同时验证新建接触模型的合理性;利用实验测试S密封圈的实际密封效果。研究结果表明:S密封圈在高压、高温、低温等工况下能够长时间稳定工作且密封性能良好。研究结果可为S密封圈的接触研究及工程运用提供理论参考。

Sealing capacity evaluation of underground gas storage under intricate geological conditions

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.

Interfacial friction effects on sealing performances of elastomer packer

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.

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

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.

Fracture sealing performance of granular lost circulation materials at elevated temperature:A theoretical and coupled CFD-DEM simulation study

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.

Dynamic evaluation on sealing capacity of caprocks of the Meso-Neoproterozoic reservoirs in Ordos Basin,China

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.

Influence of pressure disturbance wave on dynamic response characteristics of liquid film seal for multiphase pump

Slug flow or high GVF(Gas Volume Fraction)conditions can cause pressure disturbance waves and alternating loads at the boundary of mechanical seals for multiphase pumps,endangering the safety of multiphase pump units.The mechanical seal model is simplified by using periodic boundary conditions and numerical calculations are carried out based on the Zwart-Gerber-Belamri cavitation model.UDF(User Define Function)programs such as structural dynamics equations,alternating load equations,and pressure disturbance equations are embedded in numerical calculations,and the dynamic response characteristics of mechanical seal are studied using layered dynamic mesh technology.The results show that when the pressure disturbance occurs at the inlet,as the amplitude and period of the disturbance increase,the film thickness gradually decreases.And the fundamental reason for the hysteresis of the film thickness change is that the pressure in the high-pressure area cannot be restored in a timely manner.The maximum value of leakage and the minimum value of axial velocity are independent of the disturbance period and determined by the disturbance amplitude.The mutual interference between enhanced waves does not have a significant impact on the film thickness,while the front wave in the attenuated wave has a promoting effect on the subsequent film thickness changes,and the fluctuation of the liquid film cavitation rate and axial velocity under the attenuated wave condition deviates from the initial values.Compared with pressure disturbance conditions,alternating load conditions have a more significant impact on film thickness and leakage.During actual operation,it is necessary to avoid alternating load conditions in multiphase pump mechanical seals.

Preparation and property of seal coating for gas turbine compressor

Double-layer structure of seal coating which consisted of a Ni5Al bond coating and a Ni25 graphite top coating were prepared on steel substrate of gas turbine compressor cylinder block.Bond coating was prepared by atmospheric plasma spraying and top coating was prepared by flame spraying.The microstructure,mechanical properties and abradability of the coating were characterized by scanning elec-tron microscope(SEM),hardness tester,universal testing machine,thermal shock testing machine and abradability testing machine.The res-ults show that the overall spraying structure of the seal coating is uniform,the nickel metal phase is the skeleton supporting the entire coat-ing,and the coating is well bonded without separation.The seal coating has a bonding strength of not less than 7.7 MPa,excellent thermal stability,and thermal shock resistance cycle numbers at 500℃more than 50;the scratch length,deepest invasion depth and wear amount of the coating increase with rise of test temperature,with almost no coating adhesion,indicating that the seal coating has excellent abradability.

SEAL428采集设备原理分析

本文从Sercel公司用于陆地和海上勘探的428系列地震仪器产品性能特点出发,通过对比分析,总结海洋SEAL428系统的设计理念和数据采集原理。文章从两者的野外采集设备布设和连接方式切入,对比两套系统的设备架构、数据传输、设备布设灵活性、带道能力、采集设备种类、采集设备故障排查等方面的异同。重点对SEAL428地震采集仪器的数据采集原理进行分析,对SEAL428的“鬼对”传输技术、数字滤波器原理等进行深入探讨,以期为国内海洋物探装备技术提升提供参考。

Study on Sealing Characteristics of Sliding Seal Assembly of Aircraft Hydraulic Actuator

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.

Application of Choquet Integral-Importance-Performance Analysis and TOPSIS Methods in Approaching the Preference Factors of Calligraphy and Seal Engraving Imagery

Classical Chinese characters,presented through calligraphy,seal engraving,or painting,can exhibit different aesthetics and essences of Chinese characters,making them the most important asset of the Chinese people.Calligraphy and seal engraving,as two closely related systems in traditional Chinese art,have developed through the ages.Due to changes in lifestyle and advancements in modern technology,their original functions of daily writing and verification have gradually diminished.Instead,they have increasingly played a significant role in commercial art.This study utilizes the Evaluation Grid Method(EGM)and the Analytic Hierarchy Process(AHP)to research the key preference factors in the application of calligraphy and seal engraving imagery.Different from the traditional 5-point equal interval semantic questionnaire,this study employs a non-equal interval semantic questionnaire with a golden ratio scale,distinguishing the importance ratio of adjacent semantic meanings and highlighting the weighted emphasis on visual aesthetics.Additionally,the study uses Importance-Performance Analysis(IPA)and Technique for Order Preference by Similarity to Ideal Solution(TOPSIS)to obtain the key preference sequence of calligraphy and seal engraving culture.Plus,the Choquet integral comprehensive evaluation is used as a reference for IPA comparison.It is hoped that this study can provide cultural imagery references and research methods,injecting further creativity into industrial design.

Seal&Protect^(TM)对牙本质作用的扫描电镜研究

目的 通过扫描电镜观察Seal&ProtectTM封闭人离体牙牙本质小管的效果 ,探讨作用机理。方法 选择新鲜的离体牙进行脱敏治疗 ,立即制备标本 ,进行扫描电镜观察其牙本质横纵断面的结构变化。结果 对照组牙本质表面凹凸不平 ,呈弹坑状 ,牙本质小管口完全暴露 ;实验组牙本质表面呈均匀一致状 ,大部分牙本质小管被封闭 ,极少数小管外露。结论 Seal&ProtectTM能有效地封闭牙本质小管 ,达到治疗牙本质过敏症的目的。

Seal演算与Boxed Ambient演算的关系分析

研究不同演算系统之间的逻辑结构和描述能力具有重要的理论意义。本文在系统分析Seal演算与BoxedAmbient演算的语法结构和语义规约系统的基础上给出了一些等价关系:通信等价、通信原语等价和代码移动等价。最后给出了Seal演算通信进程到BoxedAmbient演算通信进程的一种结构化转换方法。

Seal演算的偶图语义

偶图反应系统是一种新的理论工具,其基础是一种强调位置和连接的移动计算图形化模型——偶图,偶图范化了π演算和移动Ambient演算的特征,能够表示具有位置和移动性质的复杂系统.偶图反应系统为普适计算不同层次的设计和实现提供了统一的建模框架.Seal演算是一种用于描述移动计算的进程语言,具有良好的安全性质.文中给出了一种不带复制进程表达式的Seal演算的偶图表示,分析了该Seal演算与其偶图表示间的结构对应和操作对应.本研究扩展了偶图理论的应用范围,展示了偶图理论在描述安全演算方面的能力,为在偶图反应系统框架下研究Seal演算的性质和应用奠定了基础.

Seal & Protect封闭剂治疗牙本质过敏症的疗效评价

目的 观察Seal＆Protect封闭剂治疗牙本质过敏症的作用,通过扫描电镜观察Seal＆Protect封闭人离体牙牙本质小管的效果。方法 牙本质过敏患牙180颗,实验组90颗,用Seal＆Protect治疗,对照组90颗用30％草酸钾治疗。取离体牙30颗,于颈部制备洞型,分3组(第1组涂布Seal＆Protect,第2组涂布30％草酸钾,第3组未经任何处理作空白对照)扫描电镜观察表面形态。结果 实验组治疗后的即刻疼痛缓解有效率100％,3个月复查有效率97.78％,而用30％草酸钾即刻疼痛缓解有效率为96.67％,3个月复查有效率87.78％,两者有显著差异(P<0.05)。SEM观察显示经Seal＆Protect和草酸钾处理,大部分牙本质小管被封闭。结论 Seal＆Protect能有效地封闭牙本质小管,是一种有效的治疗牙本质过敏症的脱敏剂。

Seal演算的等式特性

为完善Seal演算的自身性质及形式化证明移动代码的安全性,从上下文等价性角度研究了Seal演算的等式特性及其应用。首先定义了Seal演算的可观察性和上下文等价性,然后通过两个判断上下文等价性的定理给出了Seal演算上下文等价性的判定方法,最后依据上下文等价性证明了Seal演算的防火墙等式。结果表明,Seal演算上下文等价性可以正确地描述Seal演算的等式特性,并可判定Seal演算的安全特性。

DMG窝沟封闭系统Ionosit Seal临床效果研究

目的观察DMG窝沟封闭系统Ionosit Seal预防儿童恒磨牙龋病的临床效果。方法 2011年7月选择河北省廊坊市第六小学100例6-8岁儿童随机分为两组,各50例。A组一侧恒磨牙（牙数=88）选择DMG窝沟封闭系统Ionosit Seal进行窝沟封闭治疗,另一侧恒磨牙（牙数=84）采用3M Filtek Z350流动复合树脂进行窝沟封闭治疗;B组一侧恒磨牙（牙数=86）选择DMG窝沟封闭系统Ionosit Seal进行窝沟封闭治疗,另一侧恒磨牙（牙数=84）采用国产观雅窝沟封闭剂进行窝沟封闭治疗,随访6个月、1年、2年、3年,复查封闭剂保留情况和儿童患龋情况。结果术后6个月,A组3M Filtek Z350与Ionosit Seal、B组国产观雅封闭剂与Ionosit Seal的窝沟封闭剂保留率及患龋率比较差异无统计学意义（P〉0.05）。术后1、2、3年,A组3M Filtek Z350与Ionosit Seal的窝沟封闭剂保留率及患龋率比较差异无统计学意义（P〉0.05）;术后1、2、3年,B组国产观雅封闭剂与Ionosit Seal的窝沟封闭剂保留率及患龋率比较差异有统计学意义（P〈0.05）。结论采用DMG窝沟封闭系统Ionosit Seal进行窝沟封闭预防儿童恒磨牙窝沟龋的效果显著,值得临床推广应用。

A STUDY ON THE SEALING PERFORMANCE BETWEEN CYLINDER HEAD AND CYLINDER SLEEVE IN DIESEL ENGINES

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。

ProSeal喉罩联合舒芬太尼在妇科腹腔镜手术中的应用效果分析

目的:探讨Pro Seal喉罩联合舒芬太尼在妇科腹腔镜手术中的应用效果。方法:将90例妇科腹腔镜患者按随机数字表法分成Pro Seal喉罩联合舒芬太尼麻醉组(喉罩联合组)和气管插管联合舒芬太尼麻醉组(插管联合组)各45例。记录两组T0、T1、T2、T3、T4、T5的平均动脉压(MAP)和心率(HR)、气腹前后5 min的气道峰压(Ppeak)和呼气末二氧化碳分压(PETCO2)、手术结束后的苏醒时间;同时比较两组患者相关的并发症。结果:两组T1时点MAP、HR低于T0时(P<0.05),插管联合组在T2、T3、T5时点MAP、HR高于喉罩联合组(P<0.05);两组在间歇正压通气期间Ppeak、PETCO2变化比较差异有统计学意义(P<0.05);喉罩联合组苏醒时间短于插管联合组(P<0.05);喉罩联合组的并发症少于插管联合组(P<0.05)。结论:Pro Seal喉罩联合舒芬太尼麻醉用于腹腔镜妇科手术的临床效果优于气管插管联合舒芬太尼麻醉,具有安全性好,血流动力学平稳,苏醒时间短,并发症少的优点,操作简单,值得推广应用。

冠心病介入治疗术后Angio-Seal血管闭合装置的应用

目的 探讨在冠心病介入治疗术 (PCI)后应用血管闭合装置Angio -Seal止血的可靠性、安全性及临床应用价值。方法 6 3例经股动脉冠脉介入治疗术后 ,应用Angio -Seal装置止血 ,记录止血时间、下肢制动时间及血管并发症。结果 应用Angio -Seal装置血管闭合成功率 98 4 % (6 2 / 6 3)。止血时间 (49± 12 )秒 ;制动时间 (2 1± 0 8)小时 ;1例发生血肿。结论 血管闭合装置Angio -Seal是一种安全、可靠的止血方法 ,术后的止血时间及患肢制动时间明显缩短 ,并有助减少血管穿刺部位血肿等并发症的发生。