通用气门间隙调整方法

本文从理论分析入手论证了四冲程发动机气门间隙的简单调整方法.利用这种方法曲轴只转一周(360°)即可将气门间隙调整完毕,做到正确、简单、迅速,从而可降低劳动强度,提高生产效率.     

浅谈柴油机气门间隙调整

针对气门间隙对柴油机工作和安全的重要意义,阐述了气门间隙不当对柴油机产生的危害和气门间隙调整时机,并总结归纳了两类行之有效的气门间隙检查与调整方法,最后对柴油机使用维护提出了几点建议。     

160系列柴油机气门间隙的调整

气门间隙是柴油机的一个重要的调整参数,其大小与发动机的结构、型式等有关,各种发动机都规定有具体的数值。为了保证气门与气门座的工作密封性,在配气机构中的气门与摇臂间,需要留有一定间隙,这就是我们平常所讲的气门间隙。留有间隙,可以防止加工误差、气门跳动或积炭而带来的气门关闭不严;同时还可补偿气门、推杆、气缸盖等因温度变化而产生的不同伸长量,以保证密封良好。气门间隙应按规定调整,过大、过小都     

浅谈内燃机气门间隙两次调整

浅谈内燃机气门间隙两次调整河北丰润县农机化技术学校苏仲田内燃机工作中，由于气门斜面与座的磨损，气门间隙会变小；又因气门组的传动和驱动件磨损，气门间隙又会变大。这都会造成发动机功率下降。因此，应在气门完全关闭状态下定期检查和调整气门间隙。四缸或六缸发动...     

车用发动机气门间隙的确定与调整

本文根据发动机气门机构的工作特点,从物理意义出发,介绍了不同机构与气门间隙之间的关系及其气门间隙的精确计算与简略估算方法。按照这一关系及其计算方法,为发动机设计和维修人员在确定不同气门机构的气门间隙时提供一个参考。     

柴油机气门间隙的几种调整方法

以CZ4 75Q柴油机为例 ,介绍柴油机气门间隙调整的几种方法 ,此方法能保证调出的气门间隙正确 ,保证气门开度和气门的密封性 ,而不影响柴油机的动力及性能指标。     

柴油机气门间隙柔性自动调整系统设计与研究

为在同一工位实现不同型号柴油机气门间隙自动调整,设计了基于工业机器人、激光位移传感器、长度计及PLC与组态软件的柴油机气门间隙柔性自动调整系统。该系统采用一台工业机器人夹持着电动拧紧系统进行柴油机曲轴旋转,一台工业机器人夹持着凸轮基圆探测单元和气门间隙调整单元进行凸轮基圆相位探测与气门间隙大小调整。工作时,固接于机器人手臂末端的单个激光位移传感器实现机器人的精确智能定位,光栅型长度计实现对凸轮相位角信息的采样,并采用塞片法实现气门间隙大小控制。整个系统以PLC为控制核心实现信号处理、通讯及控制。该系统通过进行小样本样机试验测试,结果表明其间隙调整精度可达±0.05 mm,模拟生产合格率为98.6%,生产节拍可达550 s,极大地提高了柴油机气门间隙调整效率和质量。     

多缸发动机气门间隙两次调整简明记忆法

1前言发动机工作一段时间后，由于配气机件磨损、气门间隙变大或变小．导致发动机功率下降，因此，气门间隙需经常进行调整．这里介绍一种气门间隙两次调整简明记忆法，供大家参考．2两次调整法多缸发动机的气门间隙调整一般需两次完成，也就是通过两次摇转曲轴把全部气门分两次调整的方法．它是根据四冲程内燃机曲轴转两圈（720“）各个气缸均完成一次工作循环，每只气门在凸轮轴的作用下完成一次开启和关闭的工作原理确定的，其要点如下．先使1缸处于压缩上止点，然后调整一部分气门，再旋转曲轴1＠将最后1缸首于压缩上止点，调完剩余的气…     

气门间隙对柴油机的影响及检查与调整

分析了气门间隙对柴油机运行的影响。在此基础上,总结了气门间隙变化的判断方法和气门间隙检查与调整方法,并提出了调整气门间隙过程中的注意事项。有针对性地对气门间隙加以维护、调整,保证柴油机的正常使用。     

浅谈12V135型柴油机气门间隙的调整

简要说明了如何识别12V135型柴油机缸号及其发火顺序,并介绍了气门间隙的调整方法。     

12V180ZJC型柴油机气门间隙调整方法

1前言 12V180ZJC型柴油机为80年代后期由联合国资助,青岛四方机车车辆厂和奥地利的李斯特内燃机研究所(AVL)合作开发的产品.     

轮对空心轴式电动机全悬挂驱动装置间隙设计及调整

分析了轮对空心轴电动机全悬挂驱动装置中空心轴与车轴、空心轴套与空心轴之间间隙的重要性及其在机车运行时的作用原理,介绍了驱动装置间隙的设计及在东风9型、东风11型机车上实施的过程。     

阀门质量检验问题及对策探究

阀门是石油与化工等工业生产中必须应用的一种配件,也属于工艺部件,可以有效的满足行业生产需求。但在实际的工业生产过程中,阀门质量检验还存在较多的问题,直接增大阀门泄漏几率,引发安全事故。本文从阀门质量检验入手,深入进行分析,结合实际情况探索阀门质量检验中存在的不足,探讨全新的质量检验方法。     

国际工程质量保证体系的建立与运作——小浪底工程监理实践

随着我国与外国在经济、技术合作领域的拓展,对进行国际招标的工程项目如何进行有效地质量控制与管理,小浪底工程在全方位地与国际惯例接轨,实施业主负责,监理实施、承包商执行模式的同时,也从中国的国情出发实行政府的质量监督。通过近几年的实践建立了与中国国情相结合的质量管理与控制的模式,充分发挥参建各方作用。     

Thermal conductivity measurement of insulating materials with a three layers device

This paper presents a new method dedicated to thermal conductivity measurement of low-density insulating materials. The three layers experimental device (brass/sample/brass) and the principle of the measurement based on a pulsed method are presented. The three-dimensional modelling of the system is used for a sensitivity analysis. The estimation method is described and applied to experimental measurements carried out at atmospheric pressure and under vacuum. We conclude that the thermal conductivity is estimated with a precision better than 5% and that the precision of the thermal diffusivity estimation depends on the density of the material.     

300MW汽轮机轴承绝对标高测量装置的研究

引进型300MW汽轮机发电机组普遍存在低压缸轴承座刚度较差的问题，使得运行过程中机组轴承的绝对标高易于变化而导致机组振动增加。为此，现场往往需要精确地测出在运行时机组轴承绝对标高的变化以便准确地对机组进行异常振动故障诊断及正确地对机组进行调整、安装或维修。文章应用近代物理学中光学的干涉及微弱信号检测原理，设计了一套300MW汽轮机发电机组轴承标高测量装置，较精确地测量出轴承的绝对标高并利用计算机对标高进行现场实时统计、分析、记录。     

Optical and thrust measurement of a pulse detonation combustor with a coaxial rotary valve

We developed a rotary valve for a pulse detonation engine (PDE), and confirmed its basic characteristics and performance. In a square cross-section combustor, we visualized a multi-shot of a pulse detonation rocket engine (PDRE) cycle at an operation frequency of 160 Hz by using a high-speed camera (time resolution: 3.33 μs, space resolution: 0.4 mm) and a Schlieren method. The propellant filling process and the purge process were confirmed, and each process was modeled. Moreover, we confirmed the processes of detonation wave generation and burned gas blowdown. In addition, we investigated the impact of shortening the passage width of a combustor and negative-time ignition (ignition time is earlier than the end-time of the propellant filling process) on the deflagration-to-detonation transition (DDT) distance and time. The DDT distance did not depend on the passage width of a combustor and decreased under the negative-time ignition condition. With a passage width of 20 mm, the DDT distance decreased by 22% under the negative-time ignition condition to a minimum value (76 ± 8 mm). The DDT time from spark time reached a minimum value (69 ± 14 μs) under the condition of a passage width of 10 mm and negative-time ignition. The detonation initiation time and the DDT distance were represented by the time until the flame expanded toward the tube-axis one-dimensionally from ignition (characteristic time). We also carried out thrust measurement using a PDRE system composed of a circular cross-section combustor and the newly developed valve. We obtained a stable time-averaged thrust in a wide range of operation frequency (40–160 Hz) and confirmed the increase of specific impulse due to a partial-fill effect. At a maximum operation frequency of 159 Hz, we achieved a maximum propellant-based specific impulse of 232 s and a maximum time-averaged thrust of 71 N.     

An electrochemical device for the Knudsen and bulk diffusivity measurement in the anodes of solid oxide fuel cells

Both Knudsen and bulk diffusion mechanisms are taken into account in the anode diffusivity measurement in solid oxide fuel cells (SOFCs). The correlation of anode parameters including pore size, porosity, tortuosity and thickness with the effective diffusivity is then explored analytically. Through quantitative analysis, limiting current density and concentration polarization are investigated with various SOFC anode structures. Our work improves the understanding of the gas diffusion and electrochemical performances of SOFCs with various electrodes.     

Instrumentation for the measurement of the variation, quantity and quality of Sun and sky radiation

Many biological responses, such as reproduction, differentiation and morphological development are regulated by radiant energy in particular wavelengths of the solar spectrum. Biologists are concerned with the influence of the spectral quality of natural daylight on these biological responses. Data, concerning spectral quality of daylight over a sufficient time period, required by biologists are usually not available. The described system will provide the information with sufficient accuracy and precision to discern small but significant changes. To produce such a monitoring system, a standardization program was evolved using the original Smithsonian solar standards and instruments. These were compared to each other and finally to commercial units which were used in the monitoring system. The system was designed so that data would be accurate at 0.01 ly min⁻¹ and could be automated to give high precision readings every 3 min with errors less than 2 per cent.