某类机械设备的磨损与抗磨损研究

煤矿机械利用率极高,且大部分设备都处于大负荷高强度的长期运作状态,很容易造成机械磨损等问题,为了满足当代煤矿市场对煤矿开采量以及机械生产效率的要求,需要针对煤矿机械设备磨损问题进行深入探究。本文从煤矿机械设备工作特点以及其磨损特征切入主题,从各影响因素分析机械磨损因素,以提出具有针对性的抗磨损措施,以保证煤矿机械设备生产工作的质量与效益。     

煤矿机械磨损失效问题探讨

结合当前煤矿机械磨损失效问题,探讨机械磨损失效的分析方法,包括一般资料分析法、宏观分析与微观分析法、磨损表皮分析法和磨屑分析法等,并从设计结构、生产资料、生产技术和工艺等方面提出提高机械抗磨损能力的措施。     

港口机械抗典型磨损的堆焊工艺

在港口装卸生产中,主要依靠各种运输、装卸机械承担货物的中转、装卸。这些机械在使用过程中的部件磨损是一个普遍存在的问题,因此寻求一种比较好的抗磨损工艺,提高被磨损件的寿命,是港口机械维修人员所共同探索的课题。根据港口机械的典型磨损情况,我们查阅了国内最先进的金属抗磨损的新工艺、新材料,经过多次的试验使用,认为采用堆焊工艺是一种比较好的抗磨损办法。该工艺成本低、抗磨损时间长,可大大延长被磨损件的寿命,提高港口装卸机械的工作效率。下面简介堆焊的几种工艺方法和所需用的抗磨损材料。     

对机械结构设计之中抗磨损的改造手段分析

在机械结构运行过程中，磨损是一个常见且危害较大的问题，如降低安全系数、运转性能以及生产质量等，所以，针对机械结构设计之中抗磨损问题予以探讨，并提出相应的改造手段便显得尤为重要了。     

基于变元法的机械传动结构抗磨损设计及优化

首先介绍了变元法及链传动和齿轮传动抗磨损设计要点,然后针对链传动结构易磨损的弊端进行了抗磨损设计,并通过模糊综合评判法选择了最优方案,同时对链轮齿数、链条节距、中心距和链长等进行了优化设计。     

浅谈煤矿机械的磨损及其减小方法

通过分析机械磨损的种类和形式,总结出机械磨损的一般规律及特性,根据这些规律及特性分析了影响机械磨损的因素,提出了一些减小机械磨损的途径和方法。达到延长机械设备使用寿命,提高机械设备使用效率的目的。     

关于机械设备磨合、磨损问题研究

机械设备故障的产生,最显著的特征是出现磨损现象,机器的表面不断受到冲击、高温和腐蚀性物质的作用而导致严重的磨损。机械设备的磨损会造成机械的零部件的尺寸、形状和金属表面层发生变化,降低了机械生产的精度,严重了会引发机械故障的发生。机械的磨合、磨损问题是由于机械的摩擦而产生的,由于摩擦的机械性作用致使机械表面受到损耗,进而造成机械的表面因摩擦热而升高温度。本文对机械磨合、磨损发生的规律和形式进行探索,分析机械磨损产生的因素。     

机械磨损的元素含量分析方法在机械故障诊断中的应用

通过对机械磨损机理的分析，研究了几种机械磨损元素含量的分析方法，试图更加有效利用磨损元素监测来对机械设备的运行状态进行状态监测。通过研究分析，提出了科学的取样方式，解决了机械设备加油不定时、不定量、不能定时换油以及各磨损阶段特征不同等带来的问题，并在实际工作中得到了应用。     

烧结矿单辊破碎机抗磨损技术研究

单辊破碎机是烧结矿生产线上一个重要的部件,其工作环境与性质决定其必须具有抗高温与耐磨损的特性.针对目前单辊破碎机易磨损、寿命短的问题,首先,对其失效原因与磨损机理等方面进行了研究,得出其主要磨损形式是高温环境下带有凿削形式磨损的磨粒磨损.然后,研究了其抗磨损结构设计的方法,并对其材料选择与耐磨堆焊工艺等进行了详细分析与探讨,设计了一种抗磨损的长寿命烧结矿单辊破碎机.最后,通过工程实际使用验证了提出的单辊破碎枳抗磨损技术是可行且有效的.     

煤矿机械磨损失效问题的研究

从露天开采与井下开采两种模式分析了煤矿机械磨损失效的机理,探讨了机械磨损失效的原理,包括磨粒磨损和腐蚀磨损,提出了相应的防范对策,其中有提高机械设备材料的硬度、降低氧化磨损和制定机械设备管理制度,以期为同行提供参考。     

Experimental studies of the tooth wear resistance with different profiles in single screw compressor

The single screw compressor has been used in gas compression and refrigeration systems. However, the durability is not good as expected for the wear of its meshing pair. In order to improve the wear resistance and operation life, several new profiles of meshing pair have been proposed, but most of these new profiles have not been applied in products or verified by experiments. In this paper, an eccentric wheel abrasion test device was designed to investigate the wear resistance of different meshing pairs. Results show that dispersing abrasion area and making connect area continuous can improve wear resistance.     

装载机销轴磨损历程分析及其改进

销轴是装载机工作装置的重要连接部件,销轴的磨损失效往往造成严重的后果。通过大量试验,分析了装载机销轴磨损的历程,表明销轴的磨损历程主要分为磨合阶段、磨粒磨损阶段和粘结磨损阶段。结合虚拟样机技术和有限元技术,确定了销轴的最大磨损位置,对销轴油孔的结构进行了改进,提高了润滑效果,延长了销轴的使用寿命。     

Scratch and wear performance of prosthetic femoral head components against crosslinked UHMWPE sockets

Total hip arthroplasty is a highly successful procedure where the hip joint is replaced by an artificial ball and socket joint. Bearing wear continues to be a contributing factor to implant failure. Prosthetic femoral heads roughen in vivo which leads to increased wear. Along with the introduction of improved polyethylene which reduces wear by up to 99%, improved femoral head materials have been introduced to improve resistance to abrasion. The abrasion resistance of two of these improved femoral heads was assessed in this study and compared to a cobalt chromium (CoCr) femoral head. The resulting wear performance against a polyethylene acetabular component was assessed. The bulk ceramic (zirconia toughened alumina) femoral head exhibited superior abrasion resistance compared to CoCr (97% reduction in damage) as well as reduced wear after abrasion (97% reduction in wear). The oxide coated zirconium niobium femoral head showed inferior abrasion resistance compared to CoCr (99% increase in damage) as well as increased wear after abrasion (161% increase in wear). Both femoral head surfaces utilize hard ceramic materials, however, the thin ceramic coating on top of a softer metallic substrate of the oxide coated bearing was unable to withstand aggressive abrasion.     

芳纶纱的结构形貌对芳纶/PTFE织物复合材料摩擦学性能的影响

为了研究纱线结构形貌对织物复合材料摩擦学性能的影响,选用对位芳纶纤维,制备成3种具有不同结构形貌的芳纶纱,分别为长丝平行纱、长丝加捻纱和短纤维加捻纱。以相同的制备工艺得到3种芳纶/PTFE织物复合材料,采用多试件摩擦磨损试验机测试复合材料的摩擦学性能,并对芳纶/PTFE混编织物及相应复合材料的结构形貌、力学性能和磨损表面进行分析与探讨。实验结果表明：芳纶纱的结构形貌可直接影响纱线的断裂强度、纱线拔出强力、纱线与树脂的界面结合力,进而影响织物复合材料的摩擦学性能;在不同的磨损条件下3种混编织物的耐磨性表现有所不同,当载荷相对较低时,芳纶短纤维加捻纱/PTFE织物复合材料磨损率更低,而当载荷较高时,芳纶长丝加捻纱/PTFE织物复合材料耐磨性更好。     

船用机械密封环热-结构耦合有限元优化计算研究

以小锥度的收敛间隙为优化原则,以最大接触压力作为目标函数,以静环端面的磨损裕度为设计变量,采用一阶优化法进行机械密封环热-结构耦合有限元优化计算。优化结果表明:过大的磨损裕度使密封端面易产生外侧接触的倾向,密封系统稳定性差,外侧易出现严重磨损;过小的磨损裕度使密封端面内侧接触压力明显增大,易出现局部过度磨损现象。采用此优化方法,可以在保证内接触条件下提高密封端面接触均匀性和机械密封的热力学性能,对机械密封环的设计,制造及密封环热力状态的进一步研究具有重要的意义。     

Possibility of the Abrasive Wear Resistance Determination with Scratch Tester

Abrasion wear resistance is very important in many applications and it is not a surprise that there are many laboratory test methods for its determination. In this article, a possibility of the abrasive wear resistance determination with scratch tester, as a relatively easy and quick test method, was analysed and compared with the standard test method for pin abrasion testing (ASTM G 132). Materials used in the tests were: two ferrous-based coatings (deposited on an Al–Si alloy substrate with atmospheric plasma spraying), two aluminium-based composite materials with 10 wt% of Al₂O₃ reinforcements (produced with compocasting technique) and grey cast iron, known as a material with good abrasive wear resistance. Coefficient of friction and wear of the samples were investigated with both abrasion wear test methods and analysed in correlation with their mechanical properties.     

Gouging and sliding abrasion of austenitic manganese steels reinforced by hard phases

Boron in austenitic manganese steels leads to the formation of (Fe,Mn)₃(B,C) carboborides arranged in a cell-type microstructure.Gouging abrasion tests with a modified 300 J Charpy impact tester (copy of the “Uppsala pendulum”) reveal that these carboborides do not improve the wear resistance. This originates from their relatively low hardness compared with the work-hardened matrix, from a weak bonding to the austenite as well as from favourable conditions for unimpeded crack propagation and crack branching within the carboboride cell walls.However, pin abrasion tests on flint abrasive paper show that carboborides, hardened, for example, by additions of vanadium, substantially increase the abrasive wear resistance. This results from a supporting effect of the hard phase cell structure on the abrasive agent which consequently impedes wear of the softer matrix.     

Abrasive wear of steel against gravel with different rock–steel combinations

Wear testing equipment and tests used in research laboratories are often miniature or simplified versions of real applications. For example standardized ASTM dry sand rubber wheel abrasion test G 65 and pin abrasion test G 132 are widely used to study materials’ abrasion wear resistance. The test results, however, do not always correlate too well with the results obtained from real wear conditions. One reason for this is, for example, that in the crushing applications of mining industry the abrasive size is usually much larger than that used in the laboratory wear tests. To study the abrasive wear caused by larger size gravel, new three-body abrasion test equipment was therefore constructed. The equipment uses the pin-on-disk principle with free abrasive particles of sizes up to 10 mm. During the test the pin is repeatedly pressed against a fixed amount of abrasive that is rotating with the disk having confining walls. As the pin is prevented from touching the counterbody, only the abrasive acts as the wearing agent.Three steels of different hardnesses were cross-tested as pin–disk pairs and as pins against a rubber disk using three igneous rock gravels with different crushability properties as abrasives. The wear was measured as mass loss from both the pin and the disk, and the rock comminution was measured by sieving. The results indicate that the mechanism of wear is greatly affected by the hardness of the counterbody. When using large size abrasives, the rate of comminution is also a very important factor that can significantly affect the wear test results.     

钛、硼高铬铸铁的试验及应用

研究Ti和B对高铬铸铁组织和性能的影响表明川和B能使高铬铸铁组织细化,硬度提高,动态断裂韧性提高33％,抗磨性提高。根据装机试验,用这种铸铁铸造的衬板寿命比不加Ti8衬板寿命提高二倍。     

The abrasive wear of steels in South African soils

A high carbon steel was heat treated to produce a range of microstructures and mechanical properties. These steels were subjected to abrasion testing in stony, clay, and sandy soils. Wear rates were found to be twenty times higher in stony soil than in sandy soil and seven times greater than in clay. It was found that the relative wear resistance increased in sandy and clay soils with increase in steel hardness. In stony soils the relative wear resistance of all steels was found to be similar. An explanation for such behaviour was formulated on the basis of surface temperature heating and work hardening effects. The aggressive nature of abrasion found in stony soils was also found to give rise to the appearance of very hard white layers on the steel surfaces.