辊压磨行星齿轮减速器漏油分析

对辊压磨行星齿轮减速器漏油的原因进行了系统地分析。对预防漏油而采取的技术措施进行了全面地阐述,经生产实践证明预防漏油的技术措施效果良好。     

三环减速器的润滑与密封

简述三环减速器的特点及存在问题;从骨架油封质量不良、装配工艺不当、环境温度高、轴表面粗糙度和偏心度的影响及润滑油粘度低五方面,分析了导致减速器严重泄漏及其损坏频繁的故障原因,提出采用橡胶密封的改造措施,取得了理想效果。     

磨床主轴端漏油治理

目前，磨床砂轮主轴密封一般都采用普通单唇骨架油封，这种油封结构简单，使用方便，在一般场合下密封效果良好。但由于砂轮架主轴转速高，动压轴承所使用的2号主轴油粘度又很低，各橡胶制品厂生产的普通油封均难以达到稳定的全密封性能。     

抽油机减速器轴密封装置的改进

针对减速器渗漏油情况,将减速器轴的原机械密封改进为可调式且便于更换的弹性密封,通过可调式密封压盖使其产生弹性变形,使轴与该装置形成压力接触密封。弹性密封发生磨损时,聚氨酯密封环通过释放能量自动补偿磨损间隙。当磨损达到极限时,可通过调整固定螺栓恢复接触压力,提高轴承盖的工作寿命,为抽油机减速器长期运转不渗油、漏油提供新的技术和措施。     

浮动密封在减速器上的应用

目前我厂刮板机和皮带机用减速器上的密封形式通常采用带有骨架的唇形密封圈(骨架油封)结构。这种密封结构在有大量煤粉、泥砂的煤矿井下使用有较大的弊端,特别是在减速器输出轴和盲轴部位,因位于采煤工作面内,工作环境相当恶劣,     

变速器输出轴漏油的原因及改进方法

1.故障现象 我处2005年购置了6台2000型油井压裂车,经长期使用后,部分压裂车的艾里逊CL-T9880型变速器输出轴出现漏油故障。更换输出轴油封后使用不久又发生漏油,反复更换输出轴油封,始终不能彻底解决输出轴漏油问题。     

起重机驱动桥轮边减速器漏油原因分析及改进措施

正起重机驱动桥轮边减速器漏油会造成其润滑不良,甚至导致轮毂发热和打齿,直接影响整机使用。提高轮边减速器相关零部件的加工精度,虽有助于减少其漏油,但需要投入高精度设备,所需成本较高。本文以某型汽车起重机驱动桥轮边减速器为例,从轮边减速器结构、加工和装配过程3方面进行分析,并依据分析结果对轮边减速器结构进行了改进,使其获得了理想的密封效果。     

使用油封时对轴的改进设计

针对轴部使用油封时常见的故障,提出一种对轴部进行改进的设计方法:在轴上加衬套,衬套与轴之间用O型圈静密封,骨架油封与衬套接触,可避免轴的磨损.     

用于高(焦)炉煤气风机的非接触螺旋槽干气密封的设计与分析

论述了高(焦)炉煤气离心风机的转轴密封正被干运行非接触气体密封所取代的技术趋势。针对干式布袋除尘反吹煤气风机转速低、压力波动频繁的难点,设计了非接触螺旋槽干气密封,包括高刚度目标的螺旋槽型优化、干气密封零压力开启转速和角向动态失稳界限频率的分析、关键零件功能结构的选取以及干气密封支持系统的确定等。按照美国石油协会(API)617的规定及沈阳万得孚工业公司的标准对所设计的干气密封进行了性能检验和试验,并经历了工业现场令人满意的运行。     

输煤系统带式输送机减速器油封泄漏的分析与处理

针对北仑发电厂二期输煤系统带式输送机减速器高速端油封频繁泄漏的问题,从骨架油封的密封机理和导致油封密封失效的主要因素着手分析,结合现场生产实际,找出渗漏的原因,并采取相应的有效改进措施。     

On the input/output reduction in efficiency measurement

Inputs and outputs reduction is an important discussion in management science. In some cases decision makers (DMs) forced to reduce some inputs and as a result they have to reduce some outputs. In this paper we propose a new method to find how much some inputs/outputs of each decision making unit (DMU) should be reduced such that the total efficiency of all DMUs after reduction being maximized. For this purpose we propose an improved DEA-like model. The proposed model decreases the total inefficiency of all DMUs. We employ a set of real data to show applicability of the proposed method and the results are compared with those find in the literature.     

自卸货车升降液压缸漏油故障分析与排除

自卸货车设有多节升降液压缸筒，可2面、3面倾卸，是各类工程机械中主要的运输设备。其最常见的故障就是漏油，除了因液压缸密封元件正常老化破损造成漏油外，还有以下几方面原因，值得大家重视。     

基于模块化的数控加工中心输入输出层的软件编制

通过对控制对象、MCL语言等进行描述,介绍了在Cincinnati Milacron 10-vc上利用MCL语言对输入输出层进行的程序编制,提出了一种多层模块化软件开发的思路,具有较强的适用性.     

Decentralized output feedback stabilization for switched stochastic high-order nonlinear systems with time-varying state/input delays

This paper investigates decentralized output feedback stabilization problem for a class of switched stochastic high-order systems with time-varying state/input delays. With the help of coordinate transformations, a scaling gain is incorporated into the observers and controllers for the nominal system. Based on the homogeneous domination approach and stochastic Lyapunov–Krasovskii stability theorem, it is shown that global asymptotic stability in probability of the closed-loop system can be implemented by tuning the scaling gain. Two examples are given to demonstrate the feasibility of the proposed control method.     

Mathematical models of the simplest fuzzy PI/PD controllers with skewed input and output fuzzy sets

This paper unveils mathematical models for fuzzy PI/PD controllers which employ two skewed fuzzy sets for each of the two-input variables and three skewed fuzzy sets for the output variable. The basic constituents of these models are Gamma-type and L-type membership functions for each input, trapezoidal/triangular membership functions for output, intersection/algebraic product triangular norm, maximum/drastic sum triangular conorm, Mamdani minimum/Larsen product/drastic product inference method, and center of sums defuzzification method. The existing simplest fuzzy PI/PD controller structures derived via symmetrical fuzzy sets become special cases of the mathematical models revealed in this paper. Finally, a numerical example along with its simulation results are included to demonstrate the effectiveness of the simplest fuzzy PI controllers.     

粒子群优化算法求解多模式项目再调度问题

针对有资源约束的项目调度问题中,项目执行环境发生变更时的项目再调度问题,分析了项目执行环境变更的情况和项目再调度变更费用的构成,建立了以再调度变更费用为优化目标的多模式项目再调度模型并应用基于粒子群优化算法进行求解.在该算法中,粒子分为优先级粒子和模式粒子,实现对活动优先顺序和模式的优化.部分初始优先级粒子位置矢量通过启发式规则产生,以提高解的质量.通过仿真计算分析了关键参数的选择,并与其他启发式算法进行了比较.仿真结果表明,该算法能有效地求解多模式项目的再调度问题,在实际工程中有一定应用价值.     

Adaptive output feedback tracking of nonlinear systems with uncertain nonsymmetric dead-zone input

In this paper, the problem of adaptive practical tracking is investigated by output feedback for a class of uncertain nonlinear systems subject to nonsymmetric dead-zone input nonlinearity with parameters of dead-zone being unknown. Instead of constructing the inverse of dead-zone nonlinearity, an adaptive robust control scheme is developed by designing an output compensator including two dynamic gains based respectively on identification and non-identification mechanism. With the aid of dynamic high-gain scaling approach and Backstepping method, stability analysis of the closed-loop system is proceeded using non-separation principle, which shows that the proposed controller guarantees that all closed-loop signal is bounded while the output of system tracks a broad class of bounded reference trajectories by arbitrarily small error prescribed previously. Finally, two examples are given to illustrate our controller effective.     

可编程控制器的输入输出保护

针对可编程控制器输入单元所连接的设备性质不同、输出形式不同、输出驱动的负载类型不同,提出应采用适当的硬件保护,以保证可编程控制器系统的高可靠性。     

基于自组织I/O映射神经网络的产业链核心竞争力

为有效提升产业链竞争优势,合理、高效地配置产业链的内部资源,对产业链核心竞争力进行了研究。分析了其构成要素,建立了数学模型与指标体系,并针对产业链核心竞争力高维指标体系内存在的部分相关性高、影响度低的冗余因素,提出一种基于BP神经网络、遗传算法、粒子群算法融合的自组织I/O映射神经网络模型。基于该模型,对指标体系内的各复杂因素进行了筛选,过滤掉冗余指标因素,识别出最能反映输入输出映射关系的因素变量,并在此基础上构建了关键因素识别模型,以识别构成产业链核心竞争力的关键因素。