膨胀尾管悬挂器膨胀力有限元计算与试验研究

膨胀尾管悬挂器通过膨胀锥在本体内运动使其发生径向变形,依靠变形后本体与上层套管间的摩擦力,使膨胀悬挂器固定于上层套管实现尾管坐挂功能。膨胀力是膨胀锥驱动本体变形的关键、也是膨胀尾管悬挂器设计、现场施工的重要参数。采用LS-DYNA对影响膨胀力的多种因素进行研究,得到膨胀锥角、膨胀锥与本体间摩擦、膨胀本体结构对膨胀力的影响规律,并通过膨胀试验、金相观察进行验证分析。数据表明该方法能够较为准确的计算本体膨胀所需要的膨胀力及膨胀变形过程中本体的应力、应变。     

膨胀悬挂器本体膨胀性能试验研究

膨胀悬挂器依靠硫化橡胶的本体膨胀发生塑性变形,并与上层套管形成摩擦力悬挂尾管,橡胶起到密封和增大摩擦力的作用。悬挂较重的尾管需要增加本体长度,导致悬挂器整体结构增加,增大了悬挂器入井和施工风险。针对该问题优化本体设计,在本体外壁镶嵌金属块并硫化橡胶,通过膨胀试验验证了该方法的可行性,为掌握本体膨胀后与上层套管的接触应力,采用应力测试方法对本体膨胀过程中上层套管的应变进行了测量并计算得到接触应力,试验数据表明膨胀悬挂器经过结构优化在保证悬挂、密封性能的前提下使膨胀本体缩短,从而提高了现场施工的可靠性。     

膨胀悬挂器力学性能分析及试验研究

采用解析方法、有限元方法对影响悬挂器膨胀力的关键技术因素进行研究,得到了膨胀锥结构、本体材料等因素对膨胀力的影响规律。针对膨胀悬挂器实际工作状态,对膨胀本体在上层套管内膨胀进行了计算与试验研究,得到膨胀力、悬挂力与本体结构的关系。试验表明所采用的计算、试验方法能够较为精确的计算本体发生塑性变形所需要的膨胀力及膨胀后形成的悬挂力,研究成果为提高膨胀尾管悬挂器性能与整体结构优化设计提供了依据。     

膨胀悬挂器本体管材性能研究

要膨胀悬挂器通过膨胀金属本体与上层套管形成摩擦力悬挂尾管,本体管材的选取对悬挂器膨胀、悬挂性能参数有直接影响,为此采用有限元方法对本体膨胀过程进行计算,得到本体膨胀前后结构参数变化及膨胀力大小,并通过与膨胀试验得到的数据进行对比分析,验证了计算的可靠性。为确定本体膨胀前后强度变化,分别选取膨胀前、膨胀后样块进行拉伸试验,得到材料屈服、抗拉强度。数据表明的所选用的管材在膨胀后屈服强度、抗拉强度分别增大72.6%、7.94%。通过研究掌握了膨胀管材膨胀前后的力学、结构性能参数变化,为悬挂器结构设计、现场作业提供了参考依据。     

悬挂器旋转机构设计与试验研究

膨胀悬挂器通过旋转机构带动尾管转动提高固井质量、解决尾管入井遇阻问题,旋转机构需要传递大扭矩、具有高可靠性,是膨胀悬挂器研制的关键和技术难点。采用键槽传动机构实现旋转,通过扭矩套筒上的传动键与尾管套筒内壁的键槽配合传动扭矩,使用3D打印技术验证了机构的可行性,并利用ABAQUS有限元软件对旋转机构的强度进行了计算,得到扭矩应力关系曲线。在此基础上研制出旋转机构,通过扭矩测试试验和现场应用验证了其可靠性,数据表明所研制的旋转机构扭矩达到15000N·m,能够满足现场使用要求。     

尾管悬挂固井中钻杆接头伸长量计算模型建立

尾管悬挂固井作业过程中,钻杆受到多种载荷联合作用产生轴向变形;若注水泥施工步骤前的钻杆上提距离过短,会导致钻杆和尾管悬挂器在后续作业时重新扣合,使得起钻时悬挂器无法顺利脱手造成卡钻。通过对直井尾管固井施工过程中钻杆受载情况的分析,并基于钻杆接头与钻杆本体存在结构差异这一特点,提出了一种综合考虑结构场、温度场、压力场等因素的钻杆接头最大伸长量工程计算模型。运用该模型可以对尾管固井过程中钻杆的伸长量进行更加准确的分析计算,尽量减少卡钻事故。通过分析得知,静止状态下钻杆的轴向伸长量是最大的;对钻杆接头伸长量影响最大的因素是温度场,影响最小的因素是压力场,且温度对钻杆接头的影响要比对同尺寸的管柱的影响略小。     

尾管悬挂器在南堡油田定向井中的应用分析

研究复杂井况下尾管悬挂工艺,提高尾管悬挂器应用成功率。介绍冀东油田南堡区块常用液压尾管悬挂器的主要结构原理和应用该型悬挂器的南堡油田定向井的典型井况特点,结合该型悬挂器的结构原理和南堡油田定向井典型井况特点,分析南堡油田应用该型悬挂器的风险,并针对这些风险提出相应的技术措施。对2007—2018年间南堡油田应用该型悬挂器的情况进行总体技术分析和总结,得出这些技术措施对该井况具有适应性并具有推广意义。     

具有双防退功能的封隔器技术研究与应用

针对常规尾管顶部封隔器在尾管固井作业中所表现出来的环空封隔压力低,安全可靠性较差等问题,研制了带有组合式防退锁紧机构的单胶筒尾管顶部封隔器。封隔器将防退卡瓦与双面卡簧两种防退锁紧机构组合在一起,有效解决了胶筒在坐封后的回缩问题,保证了密封效果。同时封隔器胶筒采用了一体式设计,两侧为组合式防突环,可在封隔器坐封时膨胀,形成密闭空间,防止胶筒在高压作用下发生轴向窜动,进一步提高了封隔器封压能力。该型封隔器在完成样机试制后,进行了一系列地面性能试验,并在现场进行了现场应用,取得了良好的应用效果。     

液化气罐车用安全阀及其带压堵漏器

介绍了一种新型的液化气罐车用安全阀及其带压堵漏器的性能和工作原理。当安全阀发生泄漏时,带压堵漏器可方便快速地安装在安全阀上,达到迅速堵漏、防止事故蔓延扩大的目的。     

工程机械气顶油行车制动系统的结构改进

正1.气顶油行车制动系统目前压路机、装载机、平地机等工程机械大都采用气顶油行车制动系统。该系统主要由发动机1、空压机2、安全阀3、油水分离器4、储气筒5、脚踏制动阀6、气顶油加力泵7、制动钳8组成,如图1所示。储气筒5上安装有安全阀3,当储气简5储气压力达到安全阀3设定压力值后,安全阀3向外排气,以保持设定压力值。制动时,压缩空气从储气筒5经脚踏制动阀6到达气顶油加力泵7。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

ANGULAR DISTORTION ALLOWABLE VALUE AND ASSESS METHOD OF WELD ON COKE TOWER

A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed. Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have been explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth of angular distortion may pose too. For the coke tower with a popular structure of Dg 5 400 mm×28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be easily applied to different size of angular distortion.