往复推送链的运动精度可靠性研究

往复推送链是一种新型的链传动装置。本文简略介绍往复推送链的结构形式及工作原理后,重点阐述往复推送链运动精度的可靠性设计原理,即将链条中的链节长度、运动副间隙看作矢量,将链节长度的原始误差和运动副的磨损量看作变量,推导出输出运动位置误差的计算公式,建立了往复推送链运动精度可靠度的计算公式,找出了可靠度随着磨损量的增大而下降的关系。     

Analysis and optimization of municipal solid waste combustion in a reciprocating incinerator

A mathematical model is presented for the combustion of municipal solid waste in a reciprocating incinerator. The most preferable incinerator is determined by detailed simulation and analysis of different incinerator shapes. Furthermore, the optimal design and operating parameters are obtained by analyzing the injection angle and velocity of the secondary air. Both the results of numerical simulation and practical operation show favorable combustion state, low contaminants emission, and suitability for the combustion characteristics of Chinese municipal waste and the treating requirements. This study provides an important reference for the optimizing design and operation of municipal solid waste incinerator.     

往复式压缩机气流脉动与管路振动问题分析与解决

针对往复式乙烯压缩机管网振动严重超标的问题，通过测量振动值、分析振动原因，采取重新布管、增加缓冲罐等措施，使管线振动情况得以明显改善。     

大型高压往复式压缩机在石化领域的应用发展研究

针对国内外对活塞力≥1250kN的大型高压往复式压缩机产品的需求现状,结合多年来对国外发达国家关于大型高压往复式压缩机产品及技术的分析研究和应用研究,通过对大型往复式压缩机产品及技术在国内石化领域的应用状况分析,对在国内石化领域引进大型往复式压缩机产品、技术及国产化进行了分析论证,并在此基础上进行了归纳总结,为大型高压往复式压缩机产品及技术在国内石化领域有效使用及其国产化、设备采购、维护及管理工作等方面提供参考和借鉴。     

一种往复式送料设备

本文介绍了一种往复式送料设备,阐述了其结构方案、实施方式,介绍了具体实例。该设备被安置于两相邻机床之间,构成送料系统,可用于任意间距的两机床之间的物料运送,方便用户灵活使用。     

Experimental Study of Leakage and Friction of Rectangular,Elastomeric Hydraulic Seals for Reciprocating Motion from −54 to +135°C and Pressures from 3.4 to 34.5 MPa

Hydraulic seals for reciprocating motion are used in mechanisms, machines, and devices most commonly in automotive, aerospace, marine, and general industrial sectors. Applications vary from those of a cheap medical injector and tire pump to mechanisms controlling ultra-expensive equipment in power stations, ships, and space vehicles. Unfortunately, elastomeric seals are flexible solids with nonlinear response to changes in their environment involving stress or strain, heat transfer, interaction with fluids, and aging. Unsurprisingly, research into their performance is ongoing for more than 80 years. The present experimental study is a step toward a better understanding of sealing performance in a broad range of temperatures and sealed pressures. Hundreds of experiments were conducted in conformance to international standards and in controlled conditions within tight tolerances of all parameters, including mechanical properties, solid dimensions, and operating conditions. Rectangular elastomeric seals for aerospace applications were studied under sealed pressures of 3.4 to 34.5 MPa (500 to 5,000 lb/in²) and in ambient temperatures of ?54 to +135°C. The combined range of pressures and temperatures exceeds what is available in the literature, particularly on the low temperature side. Other parameters varied in the experiments include the seal dimensions and radial interference, the surface roughness of the cooperating shafts, and the support of seals by one or two back-up rings. The results of the parametric study, summarized in eight tables and two figures, have been sorted for ascending leakage and friction force at each of the studied ambient temperatures for quick selection of optimal values.     

往复式压缩机工艺管线振动超标与治理

针对天然气长输管线常用的往复式压缩机工艺管线振动严重超标的问题,通过对不同工况下关键测点的振动测试和压力脉动分析,结合测点的测试数据和频谱特性,得出了压力脉动是导致管线振动主要原因的认识。为了控制压力脉动以消减激振力,根据现场的工艺要求,提出了增加汇气管的缓冲容积和改善管道配置的治理措施。完成整改后,再次进行了关键测点的振动测试和压力脉动分析,数据表明:整改前后压缩机在相同工况参数下运行时,测点最大振动位移由289.76μm降低到47.2μm;最大振动速度由34.26 mm/s降低到5.18 mm/s;压力脉动也符合API 618标准的要求。同时,管线的振动烈度满足多台压缩机同时运行的要求,使得增压站的天然气处理量至少由67.41×10~4m~3/d提升到119.52×10~4m~3/d。该案例表明,对压缩机进行变工况振动测试和频谱特性分析,可方便地找出主要振动源,为管道的减振治理提供依据。     

往复式压缩机配管设计

结合具体工程实例,从设备平面布置、主要工艺管线和辅助系统管线的设计及支架设置等方面,介绍了往复式压缩机的配管设计,并具体分析了几种防振支架。     

基于近似熵的往复压缩机气阀故障复杂性测度分析

针对往复压缩机气阀故障诊断及特征样本提取存在困难,结合近似熵在度量时间序列复杂性方面具有的优势及缺陷,提出适于近似熵分析的分阶段数据划分方法,将其用于分析往复压缩机气阀振动信号与气缸压力信号。结果表明,分阶段的气缸压力信号的近似熵比整体样本数据及气阀振动信号更具一致性,并且具有明显的分类效果,能够有效识别气阀故障状态。     

Reciprocating heat-engine cycles

The performance of a generalized irreversible reciprocating heat-engine cycle model consisting of two heating branches, two cooling branches and two adiabatic branches with heat-transfer loss and friction-like term loss was analyzed using finite-time thermodynamics. The relations between the power output and the compression ratio, between the thermal efficiency and the compression ratio, as well as the optimal relation between the power output and the efficiency of the cycle are derived. Moreover, analysis and optimization of the model were carried out in order to investigate the effect of the cycle process on the performances of the cycles using numerical examples. The results obtained herein include the performance characteristics of irreversible reciprocating Diesel, Otto, Atkinson, Brayton, Dual and Miller cycles.