ABLT系列轴承疲劳寿命强化试验势在必行

随着人们对轴承研究的不断深入，疲劳寿命及其可靠性作为轴承最重要的性能，已引起各轴承生产单位及相关用户的广泛关注。但由于影响其疲劳寿命的因素太多，再加上轴承疲劳寿命理论仍需完善，进行寿命试验无疑成为评定这项指标的惟一有效途径。低载荷、高转速的常规寿命试验方法费时费力而且试验结果的可靠性差，ABLT型系列自动控制轴承疲劳寿命及可靠性强化试验机是我中心在轴承疲劳寿命强化试验机及试验方法的研究基础上进一步研制成功的。     

金属磨损自修复技术在滚动轴承上应用的试验

介绍了金属磨损自修复技术以及ART修复材料的成分、特点及修复原理,以6310轴承样本进行对比试验,对比ART材料自修复技术对轴承滚道各项技术指标和寿命的影响。金属磨损自修复技术能够修复轴承滚道的磨损,提高轴承的寿命。     

国内滚动轴承疲劳寿命试验机对比分析

对国内滚动轴承疲劳寿命试验机的结构及性能特点进行了对比分析,重点阐述了GQZS系列轴承疲劳寿命强化试验机的结构及特点,并指出了试验技术的研发方向。     

杭轴推出滚动轴承疲劳寿命及可靠性强化试验机

杭州轴承试验研究中心从80年代中期开始,引进了一台美国FederalMogul公司B-5强化试验机,承担了机械部的重点科研课题“滚动轴承疲劳寿命强化试验机及试验方法的研究”,并通过了机械部的鉴定。在完善该课题成果的基础上,进一步消化、吸收、创新,研制成功ABLT-1型（B10-60R）自动控制滚动轴疲劳寿命及可靠性强化试验机,不仅达到国外同类试验机水平,而且以优于国外同类试验机的性能价格比,满足了中国轴承行业加速轴承新产品开发的需求。经过在三种类型（ZS型、B型（美国）、B10-60R型）试验机上进行四种不同应力的10多万小时对比…     

B型试验机密封轴承改进试验方法

B型滚动轴承疲劳寿命试验机是我国五六十年代生产的主要滚动轴承疲劳寿命试验机，传统方法在该试验机上进行密封轴承试验时存在试验参数准确性差、试验数据不准确等问题。文章对上述问题进行了详细分析并提出了在该试验机上进行密封轴承试验的新方法。     

滚动轴承寿命试验机及其试验技术的现状及发展

本文概述了滚动轴承寿命强化试验机及其试验技术的现状及发展,探讨了寿命试验的设计,寿命试验数据的处理、分析.在中国轴承行业"十一五"发展规划中,重点要求开展提高滚动轴承寿命和可靠性工程技术攻关.低载荷、高转速的传统轴承寿命试验方法周期长、费用高且试验结果的可靠性差,而强化试验则在保持接触疲劳失效机理一致的前提下,大大地缩短了试验时间,降低了试验成本,从而加快了产品的开发周期和改进步伐,因此轴承寿命强化试验得到越来越多的关注、研究和应用.     

滚动轴承寿命试验机及其试验技术的现状及发展

本文概述了滚动轴承寿命强化试验机及其试验技术的现状及发展,探讨了寿命试验的设计,寿命试验数据的处理、分析。在中国轴承行业“十一五”发展规划中,重点要求开展提高滚动轴承寿命和可靠性工程技术攻关。低载荷、高转速的传统轴承寿命试验方法周期长、费用高且试验结果的可靠性差,而强化试验则在保持接触疲劳失效机理一致的前提下,大大地缩短了试验时间,降低了试验成本,从而加快了产品的开发周期和改进步伐,因此轴承寿命强化试验得到越来越多的关注、研究和应用。     

ABLT-I型轴承疲劳寿命试验机的改造

对ABLT-I型轴承疲劳寿命试验机进行系统改造,扩展了单一的疲劳寿命试验模式,可实现自动变载变速的性能试验,并重点介绍了ABLT-I型试验机改造后的工作原理和改造方法。     

轴承疲劳寿命试验技术发展趋势

结合国际国内轴承疲劳试验的现状 ,阐述了强化轴承疲劳寿命试验发展趋势。随着全球经济一体化的发展 ,轴承寿命快速试验国际化势在必行。     

滚动轴承疲劳寿命的截尾试验和寿命分布参数的估计方法

所谓轴承疲劳寿命的定数截尾试验,是在同类型寿命试验机较多时,把随机抽取的一组(几套)试验轴承同时全部装机试验,试验过程中,出现疲劳破坏轴承时,可换上非试验轴承来陪同那些未疲劳破坏的轴承一起试验,或将未疲劳破坏轴承合并机台试验,试到所需要的截尾数r套轴承疲劳破坏时停试。 本文介绍了截尾试验数据处理的一些方法,重点介绍最佳线性不变估计法;不同样本容量的完全试验所得额定寿命L_(10)和中值寿命L_(50)的置信度;在《轴承》1980年1期上继续介绍在不同的样本容量n下,截尾数r与风险值R的关系;最后对有关的问题进行初步讨论。附图13幅,表14个,参考文献4种。     

Effect of Composition and Physical Properties of Silicon Nitride on Rolling Wear and Fatigue Performance

The improved performance of silicon nitride components over all-steel bearings in several applications has been demonstrated. However, the effects of grain size, intergranular phase composition, fracture toughness, and hardness on rolling wear and fatigue performance are not completely understood. Three commercial bearing materials were tested under standard conditions and their physical properties were obtained. Wear and fatigue properties were compared to physical properties and material composition. It was found that a high fracture toughness is not required for high fatigue life and wear resistance. Total wear and fatigue life of the assembly must be considered, in addition to performance of the ceramic material alone, for specific applications. Grain boundary composition did not appear to affect the wear mechanism of these hot-isostatically-pressed materials.     

车辆机械零件的磨损与预防

磨损是车辆机械零件的主要的失效形式,按磨损机理可分为粘着磨损、磨料磨损、疲劳磨损、腐蚀磨损、气蚀和微动磨损等,通过分析车辆机械零件的磨损机理,采取合理的预防措施,可有效地提高车辆机械零件的使用寿命。     

The Effect of Adapter Crown Wear on Rated Fatigue Life of a Railroad Tapered Roller Bearing

A model is developed to describe the effects of adapter crown wear on the misalignment of a railroad tapered-roller bearing. Wear of the crowned surface results in a flat on top of the adapter. This flat, in contact with the wear plate, is shown to have the capacity to transmit a moment between the bearing and the side-frame of the truck. The magnitude of the moment transmitted is dependent on the length of the flat. These analytical results are coupled with model results from a bearing manufacturer, which give the relationship between bearing misalignment, and thus transmitted moment, and reduction in fatigue life of the bearing. The analysis indicates that a slightly worn adapter has no appreciable effect on the rated fatigue life of the bearing, but once a threshold level in adapter crown wear is reached, the bearing fatigue life will begin to decrease. Large amounts of adapter crown wear will result in significant bearing misalignment and a corresponding reduction in the fatigue life of the bearing.     

振幅对金属橡胶材料疲劳寿命的影响分析

对设计制作的固支圆盘形金属橡胶试件进行了疲劳试验,研究了振幅对金属橡胶材料疲劳寿命的影响。提出了割线刚度和等效黏性阻尼系数两个疲劳参数,分析了疲劳加载过程中承载能力和耗能能力随振动周次的变化趋势,并以疲劳参数为基础建立了金属橡胶材料疲劳损伤与振动周次的数学模型。结果表明,小振幅的初始稳定加载有助于改善金属丝线的力学特性,提高金属橡胶材料的承载能力和耗能能力,而振幅的增大会导致金属橡胶材料疲劳寿命的迅速缩短。     

Wear characterisation of small PM rotors and oil pump bearings

The mechanical, micro and physical properties exhibited by PM rotors and journal bearing employed in oil pumps of automobiles, decides life of the pump. In this work, the factors that markedly characterise wear are featured. Tip clearance between the driving and driven gears influences the volumetric efficiency of the pump. When the tip clearance exceeds 0.20 mm (0.007 in.), and the face clearance exceeds 0.1 mm (0.004 in.) the discharge drops below the desired volumetric efficiency of 70%. Relationships between microstructure, micro-hardness, surface roughness, tip clearance of fresh and worn out parts are investigated. PM bearing bushings are finding increasing use in automobiles and consumer durable products owing to favorable size to weight ratio and cost advantages. Superior life and torque characteristics of PM bearings are related to density, size and geometry. Bushings at 6.8 g/cc with a 0.8 μm bearing clearance were determined to give improved life. Apart from the conventional wear test practices in industries, the concept of accelerated wear test (AWT) is employed to simulate equivalent wear on rotors and bearings; the results obtained are compared with the actual field samples. An empirical data on wear behavior is arrived from experimental studies, which can be used for simulated endurance test of these parts. Possible remedies applicable to achieve optimum life are identified. By optimising the material properties, higher wear resistant PM rotors and bearings could be manufactured economically.     

An experimental investigation of wear and fatigue life reduction of boundary lubricated spherical roller thrust bearings

Wear and fatigue life reduction in boundary lubricated spherical roller thrust bearings has been investigated. Previously presented results from measurements show that there is a significant change in the washer profile due to wear. This change in surface profile greatly affects the fatigue-life of the bearings. A fractional factor experiment series was used to study how the contacting surfaces of the bearing were affected by the rotational speed, load, hardness of the contacting surfaces and type of oil. The results show that the fatigue life and amount of wear on the washer surfaces were affected by the type of lubricant and rotational speed. A change of the load or a change of the hardness of the contacting surfaces did not influence the wear or the fatigue life of the contacting surfaces.     

Rolling Contact Fatigue Evaluation of Advanced Bearing Steels with and Without the Oil Anti-Wear Additive Tricresyl Phosphate

The effect of the oil anti-wear additive tricresyl phosphate (TCP) on rolling contact fatigue (RCF) life of advanced bearing steels—AISI VIMVAR M50, CSS 42L, Pyrowear 675, and Cronidur 30 was investigated with silicon nitride balls at 177 °C and at a maximum Hertzian stress of 5.5 GPa. TCP at 1% additive concentration was blended into a synthetic polyol ester turbine engine lubricant basestock having a nominal viscosity of 3 cSt at 100 °C. Additionally, the basestock was fortified with the anti-oxidants dioctyl-diphenyl amine (DODPA) and phenyl-α-napthyl amine (PANA) at 1% concentration each. The presence of TCP has a measurable positive effect on RCF life and wear. Also, all the advanced bearing materials exhibited superior fatigue life compared to conventional bearing steel M50, both with and without TCP. The study indicates that current gas turbine lubricant formulations with TCP have positive effects on fatigue life and wear performance of M50, Pyrowear 675, CSS 42L, and Cronidur 30.     

复合添加剂摩擦磨损性能的研究

边界润滑条件下 ,承载能力主要取决于添加剂的性能 ,含有聚合剂的润滑油在极压状态能在运动副接触表面形成原位聚合膜 ,较大幅度地提高疲劳寿命 ,降低摩擦、磨损。极压添加剂对防止胶合破坏效果较好 ,将上述二种添加剂复配进行协同试验 ,可以得到对疲劳和胶合都有较好作用的润滑油 ,提高润滑油使用性能和扩大应用范围。在含 0 .4%二聚酸 /司本 -80的 46# 精制矿物油中添加 1.5 %重极压齿轮油可使其 PB 增加近 68 ,PD 增加 2 8% ,磨痕直径减少约 3 8% ,疲劳寿命较 46# 精制矿物油提高近 3 3 % ,FZG达到 12级     

Metal forming oils: How their application increases tool life

Metal forming oils can contribute considerably to increased tool life, thus reducing production costs. Low tool wear, good surface finish of the workpiece, no clinging of waste material to the tool in punching, no bulging of the side wall in deep drawing, easy removal of the oil, no workpiece and tool assembly corrosion, and minimum health risks are the most important performance characteristics to be met by a metal forming oil. Low tool wear and thus a long tool life are best realized if elastohydrodynamic (ehd) lubrication conditions are present in almost all stages of the process. Several examples of metal forming operations are given in which a long tool life has been achieved     

Gas release during wear I. The phenomenon and preparations for identification

Experiments on the sliding wear phenomena of bearing materials with solid particles in the oil film have revealed that with a tin-aluminium alloy gas is released. However this did not occur with white metal or copper-lead. Gas was again released when clean oil was used. One analysis of the released gas by mass spectroscopy showed it to consist chiefly of air with a small percentage of hydrogen, several orders of magnitude higher than normally found in dry air.Gas is also released by scratching aluminium, zinc and a magnesium alloy in straight mineral lubricating oil, liquid paraffin, silicone oil as-received or dried, and also in glycerol and water. Copper, brass, white metal, mild steel and titanium showed very little or no gas evolution.The literature on the effect of hydrogen on rolling bearing life is briefly reviewed and the possible effect of hydrogen on sliding wear is discussed.