煤矿立井提升系统可靠性的研究

通过对可靠性理论的分析,建立了煤矿立井提升系统的可靠性模型,以对其提升结构进行分析研究,构建了以可靠性为核心的立井提升系统维修方法和理论,以极大地提升煤矿立井提升系统在工作时的可靠性和安全性。     

谐波测试法在煤矿提升机罐笼振动故障诊断中的应用

以某煤矿为例,煤矿副立井大罐笼提升系统在提升和下放过程中,当罐笼速度为2.5~4 m/s时出现声音较大的异响和振动。为了查明原因,对该煤矿提升机电控系统的谐波进行现场测试,根据测量结果分析可知,电控系统谐波是提升机罐笼在运行过程中产生振动的根源,为全面分析煤矿提升系统罐笼振动的故障诊断提供了比较简便的解决方法。     

基于ANSYS的煤矿立井抢险排水管道振动模态分析

建立了810 m煤矿立井抢险排水管道结构的有限元模型,利用有限元分析软件ANSYS对其进行模态分析,得出了管道结构固有频率和振型,验证了管道结构的强度及稳定性,为煤矿立井抢险排水系统的可靠运行提供了依据。     

忻州窑矿副立井提升机自动罐帘门系统的设计与应用

对大同煤矿集团有限责任公司所属矿井的19部副立井提升机进行了调研,并对罐帘门优、缺点进行了详细的分析研究,结合《煤矿安全规程》及有关规定对罐帘门的要求,设计了安全、可靠、适用性强的自动化罐帘门。通过在现场应用,效果良好,为煤矿副立井提升机运输人员和物料提供了安全保障,保证了矿井安全高效生产。     

煤矿立井装载用板式定量输送机技术

介绍了立井箕斗装载系统规范要求,分析了板式定量输送机的构成及运行,并对板式定量输送机关键技术进行研究。立井装载用板式定量输送机的应用,可降低煤矿的生产周期,延长设备使用寿命,提高生产能力。     

煤矿进风立井破碎筒壁支护技术

基于进风立井井筒在施工过程中基岩段出现严重破碎现象,导致井筒施工难度大、危险系数高以及支护难度大等问题,古城煤矿通过技术研究,决定对基岩段破碎筒壁提出了“注浆加固+自锁式锚杆”等联合支护技术。通过实际应用效果来看,立井井筒破碎段采取联合支护技术后,控制了围岩破碎现象,保证了井筒安全顺利施工,取得了显著应用成效。     

管路内径对箕斗定重称载液压系统性能的影响

王石凹煤矿的立井箕斗定重称载系统容易出现液压元件和管路受损,并存在响应滞后和称重不准确等问题。以定重称载液压系统为研究对象,采用AMESim建立了定重称载系统的仿真模型,分析了液压管路内径对箕斗定重称载液压系统响应速度、准确性及系统刚度等指标的影响。结果表明:当管路长度一定时,系统的超调量和调整时间随管道内径的增大而增大,固有频率、阻尼比、相对误差与刚度随管道内径的增大而减小。建议采用装载过程中压力值增量计算系统相对误差,此时得到的相对误差值小且稳定。     

副立井直流提升机制动系统恒减速改造

在技术的改革以及设备的更新换代下,传统的多绳摩擦提升机已经无法满足副立井的提升运行需求,而恒减速系统则是未来发展的必然趋势。因此,对传统的提升机进行改造具有重要的价值。本文主要探究副立井直流提升机制动系统恒减速改造。结合某矿场的副立井,探究直流提升机系统的改造方式,并且对具体的技术参数进行分析,通过改造,系统达到运行的需求,且保障了运行的安全性。希望通过本文的分析,可以为煤矿企业的发展提供可行性建议。     

三电平变频器在立井提升机中的应用

通过分析立井提升机运行过程中复杂的加减速工况需要，根据对电机制动作业以及调速设计上的高精度要求，设计出三电平变频器，并将其应用于煤矿立井提升机的速度调节当中。基于实际设备配置构件仿真试验对EESM波形图进行分析，可以看出整体三电平变频器具有良好的调速稳定效果，可靠性较高，设计工作取得有效成果。     

煤矿副井操车系统设计

为了保证高效采煤,更好地适应当前煤矿开采要求,升级完善了当前的煤矿副井操车系统。明确煤矿副井操车的改进目标,在分析系统结构的基础上,制定可行的改进方案,完善副立井操车系统控制过程。改进后,副井操车系统的工作效率得到明显提升,获得了预期的开采效果。改进完善煤矿副井操车系统可以切实提高开采效率,为企业带来更大的经济效益。     

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...     

On the Relation of Load to Average Gap in the Contact Between Surfaces with Longitudinal Roughness

A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.     

三绕组变压器的双绕组等效建模及在Matpower中的应用

针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

电站锅炉模糊风险评价方法研究与应用

针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。     

考虑进油孔有限长滑动轴承油膜力的近似解析解

针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。     

交通荷载作用下桥梁结构参数识别方法

应用动力节点加载法,将作用在桥梁上的交通荷载转化为等效节点荷载,再用两步构造法识别结构物理参数.第1步,用Newmark-β方法变换结构运动方程,并用结构的加速度响应求得变换空间内的位移、速度和加速度响应;第2步,基于最小二乘原理,构造出变换空间内求解结构参数的递推式,进行结构物理参数识别.数值模拟结果表明,在交通荷载作用下,该方法能够快速、准确地进行桥梁结构参数识别.     

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.     

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....