浅析柴油机气缸套磨损和拉缸原因及预防措施

气缸套磨损、拉缸是柴油机运行过程中常见的现象,为了减少柴油机运行故障,提高柴油机使用效益,降低用户的经济成本,文章对气缸套磨损和拉缸的常见原因进行了分析,并提出几点有效的预防措施。     

BFM1013型柴油机拉缸预防措施

<正>一台6 3 3 M型起重机使用的BFM101 3型柴油机突然出现拉缸的严重故障,工作时能明显听到异响。检查发现,是Ⅵ缸中度拉缸。影响拉缸的因素很多,情况也比较复杂。它主要与柴油机的工作温度和负荷、活塞与缸套的材料匹配和配合间隙等有密切关系。     

某型柴油机拉缸故障原因分析与处理

对某型船用主柴油机在修后航行试验过程中出现的拉缸故障停车现象,进行了原因分析和故障排除,恢复了舰船动力设备的性能,保证了修理工程的顺利进行.     

某型柴油机拉缸故障原因分析

本文针对某型柴油机在使用过程中发生机体被打破,平衡块和连杆小端甩出机体外部的故障,通过对柴油机故障现象、相关零部件的拆检分析,确定了故障原因是由于气缸盖摇臂座紧固螺钉孔存在缺陷发生开裂,摇臂座紧固螺钉松脱,造成柴油机工作过程中该缸配气系统失效,燃油稀释缸套油膜,引起拉缸,导致活塞拉断,连杆小头失去约束从而发生一系列故障。     

某型柴油机拉缸原因分析及解决措施

本文针对某型柴油机在国产化过程中出现的拉缸问题,从原理上分析了某型柴油机拉缸的原因,并提出了在制造、安装、使用过程中应采取的预防措施。     

柴油机过热和拉缸的预防

（1）水温偏高 装载机工作环境多尘土，在风扇的作用下，气流由前向后高速通过水散热器，空气中部分尘土附着在水散热器的表面上。这些尘土用水难以洗掉，从而使水温偏高，甚至经常开锅。再者由于发动机长时间在高速、大负荷条件下工作，水温偏高甚至经常开锅。     

BFM1O13型柴油机拉缸预防措施

一台6 3 3 M型起重机使用的BFM101 3型柴油机突然出现拉缸的严重故障,工作时能明显听到异响。检查发现,是Ⅵ缸中度拉缸。影响拉缸的因素很多,情况也比较复杂。它主要与柴油机的工作温度和负荷、活塞与缸套的材料匹配和配合间隙等有密切关系。     

XST型数字式柴油机测缸仪研制与应用

介绍XST型数字式柴油机测缸仪基本原理、使用方法及使用效果。     

预防柴油机拉缸与烧活塞的措施

（1）确保活塞与气缸有合理的配合间隙更换新活塞与气缸时,要保证合理的配合间隙。确定此间隙有3种方法。①计算法。计算法仅从温度引起的热膨胀考虑,只是从理论上进行研究,实际应用还存在一定的问题,所以这种方法没有得到广泛的应用。     

柴油机拉缸的原因及注意事项

柴油机拉缸是指缸套被活塞组件拉伤的故障。拉缸可通过发动机的响声和排气冒烟来判断,轻微拉缸一般不易听到;较严重的拉缸可听到一种尖锐的像活塞敲缸的声     

Effect of Carbon Coating on Scuffing Performance in Diesel Fuels

Low-sulfur and low-aromatic diesel fuels are being introduced in order to reduce various types of emissions in diesel engines to levels in compliance with current and impending U.S. federal regulations. The low lubricity of these fuels, however, poses major reliability and durability problem for fuel injection components that depend on diesel fuel for their lubrication. In the present study, the authors evaluated the scuff resistance of surfaces in regular diesel fuel containing 500 ppm sulfur and in Fischer-Tropsch synthetic diesel fuel containing no sulfur or aromatics. Tests were conducted with the high frequency reciprocating test rig (HFRR) using 52100 steel balls and H-13 tool-steel flats with and without Argonne's special carbon coatings. Test results showed that the sulfur-containing fuels have about 20% higher scuffing resistance than does fuel without sulfur. The presence of the carbon coating on the flat increased scuffing resistance in both regular and synthetic fuels by about ten times, as measured by the contact severity index at scuffing. Coating removal was observed to be a necessary, but not sufficient condition for scuffing failure in tests conducted with coated surfaces. The loss of coating from the surface occurred by the two distinct mechanisms of spalling and wear.     

船舶柴油机缸套活塞环微观滑动接触模型研究

本文根据模拟试验的相似准则设计了磨损试验,得出硬化相的性能和含量与试验所选用的材料在性和一致,且随着载荷的增加,材料发生拉毛的时间呈指数关系下降。在此基础上建立了摩擦配对副三滑磨面接触模型,为更好地解释内燃机气缸套及活塞环的磨损现象提供了理论依据。     

基于广义贴近度的船用柴油机磨损模式识别方法

在总结船用柴油机磨损形式的磨粒分析基础上,分析了模糊逻辑方法进行模式识别的不足,提出在船用柴油机磨损模式识别中极用基于广义贴近度的模糊模式识别方法,建立相应模式识别专家系统,并验证了识别结果的可靠性。     

Infrared and Visual Study of the Mechanisms of Scuffing

The development of a reliable model for predicting scuffing requires an understanding of the mechanism of scuffing initiation. This study examines the process of scuffing directly within a contact and thus tests some of the existing, proposed mechanisms.

A lubricated steel ball is loaded and rotated against a sapphire flat and the load increased in stages until scuffing occurs. Two methods of observation are employed. In one, the temperature of the steel ball across the contact is mapped continuously using an infrared microscope. A novel, nodding mirror set-up enables temperature profiles to be taken many times a second. This work shows that scuffing does not occur at either a critical maximum or at a critical inlet temperature. In the second approach, a solid-slate TV camera and video recorder are used to monitor the contact visually up to and during scuffing. This work suggests that, for a range of different lubricants, the onset of scuffing is always immediately preceded by the buildup of fine wear debris in the contact inlet. This then causes starvation followed by extremely rapid scuffing in the rear of the contact.

From these findings, an alternative method of scuffing based upon the influence of wear debris on lubricant film thickness is proposed.     

Scuffing Performance of Amorphous Carbon During Dry-Sliding Contact

Scuffing is a major problem that limits the life and reliability of sliding tribo-components. When scuffing occurs, friction force rises sharply and is accompanied by an increase in noise and vibration; severe wear and plastic deformation also occur on the damaged surface. Attempts have been made over the years to combat scuffing by enhancing the surface properties of the machine elements, and by methods involving lubricant formulation and coating application.

In this study, the authors evaluated the scuffing performance of an amorphous, near-frictionless carbon (NFC) coating that provides super-low friction under dry sliding conditions. The test configuration used a ball-on-flat contact in reciprocating sliding. The coating was deposited on HI3 steel. An uncoated 52100 steel ball was tested against various coated flats in room air. Compared to uncoated surfaces, the carbon coating increased the scuffing resistance of the sliding surfaces by two orders of magnitude. Microscopic analysis shows that scuffing occurred on coaled surfaces only if the coating had been completely removed. It appears that depending on coating type, the authors observed that coating failure occurs before scuffing failure by one of two distinct mechanisms: the coating failed in a brittle manner and by spoiling, or by gradual wear.     

The Role of Soot Aggregation on the Lubrication of Diesel Engines

This paper deals with the role of the soot on the valvetrain wear in diesel engines. First, wear is related to the soot aggregation at the inlet, of the cam-tappet contact. Then, an experimental device using a Rayleigh pad which allows one to study the aggregation underflow of diesel soot in completely formulated oils is described. The results concerning four oil samples, chosen for their differences in formulation and aging are given and related to the wear. Finally, the aggregation is related to the interparticle interactions and, more particularly, to the dielectric constants of the soots and of the lubricant.     

柴油机磨损趋势预测

本文应用灰色系统理论的ＧＭ（１,１）预测模型,运用直读铁谱实验的数对柴油机磨损趋势进行了在线预测。重要的是,灰色系统理论－校正模型能够识别柴油机工况变化引起的直读铁数据的变化,正确判断其磨损趋势,实现对柴油机摩擦磨损趋势进行在线预测,其最大的特点是建模所需样本数据少,计算简单,预测准确。     

Experimental Validation of Critical Temperature-Pressure Theory of Scuffing

A series of experiments was conducted for validating a newly developed theory of scuffing. The Critical Temperature-Pressure (CTP) theory is based on the physisorption behavior of lubricants and is capable of predicting the onset of scuffing failures over a wide range of operating conditions, including the contacts operating in the boundary lubrication and in the partial elastohydrodynamic lubrication (EHL) regimes. According to the CTP theory, failures occur when the contact temperature exceeds a certain critical value which is a function of the lubricant pressure generated by the hydrodynamic action of the EHL contact. A special device capable of simulating the ambient conditions of the partial EHL conjunctions (of contact temperature, pressure, and the lubricant pressure) was constructed. A ball-on-flat type wear tester was put inside a pressure vessel, completely immersed in a highly pressurized bath of mineral oil. The temperature on the flat specimen was gradually increased while the ball was slowly traversed. At a certain critical temperature, the friction force abruptly jumped indicating the incipiency of the lubrication breakdown. This experiment was repeated for several levels of hydrostatic pressure and the corresponding critical temperatures were obtained. The test results showed an excellent correlation with the newly developed CTP theory.     

Prediction of Scuffing Failure Based on Competitive Kinetics of Oxide Formation and Removal: Application to Lubricated Sliding of AISI 52100 Steel on Steel

A method for predicting scuffing failure based on the competitive kinetics of oxide formation and removal has been developed and applied to the sliding of AISI 52100 steel on steel with poly-α-olefin as the lubricant. Oxide formation rates were determined using static oxidation tests on coupons of 52100 steel covered with poly-α-olefin at temperatures of 140°C to 250°C. Oxide removal rates were determined at different combinations of initial average nominal contact pressures (950 MP a to 1578 MP a) and sliding velocities (0.4 m/s to 1.8 m/s) using a ball-on-disk vacuum tribotester. The nominal asperity flash temperatures generated during the wear tests were calculated and the temperatures corresponding to the intersection of the Arrhenius plots of oxide formation and removal rates were determined and taken as the critical failure temperatures. The pressure-velocity failure transition diagram was constructed by plotting the critical failure temperatures along isotherms of average nominal asperity flash temperatures calculated at different combinations of contact stress and sliding speed. The predicted failure transition curve agreed well with experimental scuffing data.