抗微动磨损性能是衡量乘用车轮毂轴承润滑脂优劣的重要指标,以不同稠化剂配方的聚脲润滑脂为分析对象,采用FALEX微动磨损测试仪测试润滑脂抗微动磨损性能,并从油膜厚度、流变性能等方面分析因稠化剂组成不同造成的抗微动磨损性能差异.结果表明:具有良好的油膜形成能力和油膜稳定性的润滑脂具有更好的抗微动磨损性能;稠化剂结构强度较小、可恢复能力较强、更容易流动的润滑脂的抗微动磨损性能更优.

基于脂润滑球轴承动态击穿电压测试方法,即击穿电压越大,油脂导电性越差,考察基础油黏度、有机胺类型对脲基脂导电性的影响,同时评定不同无机碳系填料对脲基脂导电性的差异.结果表明:不同基础油黏度的同类脲基脂击穿电压不同,黏度越大击穿电压越大;脲基脂导电性与稠化剂结构有较大的相关性,相同制备工艺下脲基稠化剂类型决定了油脂分油特性,分油越小击穿电压越大;添加了不同无机碳系填料的脲基脂击穿电压不同,且经高温滚压后出现不同程度的导电性增强或衰减.

出于环境保护的压力和技术进步,连铸机轴承润滑脂也朝着提高使用性能和降低消耗量的方向发展.对连铸机轴承的失效原因及对润滑脂的性能要求进行了分析,研制了一款环保型绿色复合磺酸钙润滑脂用于连铸机轴承的润滑,该润滑脂具有优异的高温性能,极压性能和抗水性能.台架试验表明,研制的复合磺酸钙润滑脂具有良好的抑制轴承温升的能力.经过3个月的实际应用,从摩擦学性能,抗磨损性能,流变学特性,稠化剂纤维结构及轴承润滑状态等方面对使用后的润滑脂进行了评估,表明研制的复合磺酸钙润滑脂完全能够满足连铸机轴承的润滑要求.润滑脂的月消耗量降低了30％～40％,减少了水体污染,同时也降低了废润滑脂的处理量和处理费用,呈现出良好的经济效益和绿色环保效应,可在连铸机上推广使用.

在聚脲基础脂中添加不同导电材料制备导电轴承润滑脂,分别采用体积电阻率测试法和脂润滑轴承动态击穿电压测试法评价导电润滑脂在球轴承中的导电特性.结果 表明:脂润滑轴承动态击穿电压测试更加适合轴承用导电脂的导电特性评价;润滑脂的击穿电压随导电材料添加量的增大而下降,不同的导电材料导电效率不同;低击穿电压伴随着低击穿电流,与高击穿电压相比具有更低的击穿放电功率;在脂润滑滚动轴承动态导电性能测试中存在"导电环"现象,润滑膜被击穿后即使降低电压润滑膜依然处于导体状态,导电环的面积大小可用于评价润滑脂的导电性能,导电环面积越小导电性能越好.

润滑是摩擦学的重要组成部分,良好的润滑能够降低摩擦与减少磨损,降低设备功耗,提高能源利用率.在所有润滑剂中,润滑脂具有其他润滑剂不可替代的独特性能.随着现代工业的发展,在高载荷与高温下运转的机械对润滑脂的长寿命与润滑性提出了更高的要求.2018年,在种类繁多的润滑脂产品中,复合铝基润滑脂约占4％的市场份额[1].

根据汽车玻璃升降器的使用工况和常见使用情况分析,得出其润滑要求,通过对基础脂和添加剂的筛选,以及一系列理化性能评价,研制了长城汽车玻璃升降器专用润滑脂.试验结果表明,该产品具有优良的胶体安定性、储存安定性、耐高低温性、抗摩擦磨损性、抗氧化安定性、抗水性、防腐蚀性和防锈性等,产品通过了客户的玻璃升降器寿命耐久性台架试验,满足客户指定的VDA270气味测试和欧盟ELV六项检测要求.近四年在市场上应用效果良好,能够较好地满足玻璃升降器的润滑使用要求.

为研究润滑脂对More Quiet噪声测试的影响,采用608微型精密轴承进行测试,对不同工作锥入度、洁净度和纤维结构的润滑脂进行分析测试,结果表明:适当增大润滑脂的工作锥人度会提高润滑脂的噪声等级,润滑脂的洁净程度越高,纤维结构越短小均匀,噪声等级越高.静音性能优异的润滑脂具有优异的机械、胶体安定性能.

稠化剂是润滑脂的主要组分,其结构与组成决定润滑脂的重要性能.以锂基润滑脂为研究对象,利用MS,XRD,SEM等分析手段,采取结构模拟与试验验证的方法,考察生长与破坏过程中稠化剂纤维的结构变化,目的是研究稠化剂纤维的生长机理.结果 表明:稠化剂纤维是稠化剂分子的聚集体,其生长过程是稠化剂分子有序排列的结晶过程;稠化剂纤维三维方向的生长情况不同,宽度方向优先生长,长度方向随后生长并引起扭转;其破坏过程与生长过程基本相逆,变化趋势与C模型更为相近.

润滑脂是将稠化剂分散到基础油中并复配添加剂形成的胶体分散体系,其产品性能主要取决于组分性能.根据稠化剂的类型,润滑脂分为锂基润滑脂、聚脲基润滑脂、磺酸钙基润滑脂、硅润滑脂、膨润土润滑脂等,并被广泛应用于各类机械设备中.润滑脂的组成、结构、性能之间存在着关联性,润滑脂的微观结构一定程度上决定了润滑脂的使用效果.润滑脂微观结构是以稠化剂纤维(也称皂纤维)为主体结构,基础油吸附在皂纤维周围,整体构成空间网状结构[1],其中稠化剂纤维的微观结构是研究重点.

对4种轮毂轴承润滑脂进行机械安定性、流变性能、抗水性、黏附性、分油性能测试,对比其使用性能,选择相同的车辆类型、轴承和试验条件进行行车试验.结果表明:新型复合锂稠化剂结构的润滑脂各项性能指标优良,满足行驶里程要求,可以为轮毂轴承提供良好的润滑,提高了车辆行驶的安全性和可靠性.

作为铁路列车的关键部件,列车轴箱轴承的性能及可靠性随着列车的高速化也受到了越来越多的关注[1].列车轴箱轴承除了要支承列车重量及车辆载重所构成的静态和动态的径向负荷外,还要承受车轴方向额外的非稳定力,其可靠性对列车的安全运行具有重大影响.高铁轴承润滑脂作为轴箱轴承的重要组成部分,在中国的发展还几乎为零,产品主要依赖进口.随着国内高铁的快速发展,高铁轴承润滑脂用量也会日益增加,依赖进口的生产模式会导致成本会越来越高,因此未来高铁轴承润滑脂的设计开发将是一个大的趋势,发展自主知识产权的高铁轴承润滑脂技术迫在眉睫.

差示扫描量热法(DifferentialScanning Calorimetry),作为一种多用途、高效、快速、灵敏的分析测试手段,已广泛用于研究物质的物理变化和化学变化过程.这些变化是物质在加热或冷却过程中发生的,它在热流曲线上表现为吸热或放热的峰或基线的不连续偏移.差示扫描热量仪(简称DSC)是一种多功能的量热仪器,可测定物质的熔融热、相变热、结晶热、氧化过程等,也可用于新材料热韧性和化学性质的测定.

The rheological and tribological properties of four kinds of heavy vehicle grease were studied, the influence of types and viscosity of base oil, types and contents of thickening agent and tackifier on the rheological properties of grease at different temperatures was analyzed; the tribological performance of four kinds of lubricating grease was determined by the rheometer, the change of friction coefficient of grease under different pressure and speed was investigated. The results showed that: in the rheological test, LX-4 and LX-2 grease showed excellent high temperature performance, which indicates that these two kinds of grease has the excellent performance including high temperature sealing performance and high temperature adhesion; LX-4 showed excellent lubricating properties under high and low temperature. In the tribological test, LX-2 grease exhibited a low friction coefficient, especially in the 50N high-pressure area, LX-2 entered more easily into the thin film lubrication area, lubricating film was formed more easily, the friction coefficient decreased rapidly.

炉渣是高炉的主要副产品之一.根据各厂原燃料的不同,吨铁炉渣量在300～450 kg.我国是钢铁生产大国,因此每年的高炉炉渣产量相当可观[1].高炉炉渣的处理方法分为干渣法和水渣法2种.其中水渣法是在炉前用高压水将炉渣冲制咸水渣,再经过渣水分离的工艺.

Noise performance of three kinds of commercially available low-noise greases are respectively tested by dif-ferent vibration test equipment and evaluation method.The results show that the measured noise level order for three kinds of greases is consistent and comparable qualitatively.BeQuiet+and MoreQuiet should be preferred in the labora-tory or for controversial cases.

以150BS为基础油,对国内外生产的10种不同类型的有机膨润土的稠化能力及成脂性能进行了考察,认为美国南方黏土公司生产的有机膨润土B和浙江临安生产的有机膨润土F类型一致,基本组成和结构相当,均属于脂肪酸氨基酰胺覆盖剂类型的有机膨润土.用其稠化150BS基础油,均能够制成高温性能及抗水性能优异的润滑脂,产品性能与国外同类产品相当,部分指标优于国外同类产品.

A mathematical model for accurately calculating heat generation rate in a grease-lubricated spherical roller bearing (SRB) is established in this paper by adopting the local heat source analysis approach, which involves in calculating heat generation rates of roller–raceway contact, cage and inner ring land contact, roller and cage pocket contact, and power loss of roller churning. Numerical calculating results show that the total heat generation rate of SRB increases as the inner ring rotating speed and radial load increase. The heat generated by roller–raceway contact is the dominant part in the total heat generation rate of the SRB. Some SRB geometrical parameters, such as diametral clearance and roller–raceway osculation, also have some effect on SRB heat generation rate.

Based on a set of formulae for calculating elliptical contact parameters and elastic deformation developed by Houpert and mechanical analysis, a numerical model is established for calculating the roller load distribution and shaft axis orbit of spherical roller bearings with considering off-sized rollers in this paper. A numerical calculation example is carried out to investigate the effects of single off-sized roller and multiple off-sized rollers on spherical roller bearing roller load distribution and axis orbit. Results show that the roller maximum load will increase as its off-sized diameter becomes larger than the nominal diameter, and the roller maximum load will decrease as its off-sized diameter is smaller than the nominal diameter. The maximum loads of the rollers in the two rows neighboring on the off-sized roller/rollers can also be affected. Meanwhile, roller diameter error will largely affect the axis orbit and inner ring radial displacement of spherical roller bearings.

Lithium greases containing different kinds of tackifiers were prepared,and their cone penetration and similar viscosity were tested.The influence of tackifier types on the rheological properties were studied by rheometers in two differ?ent test modes,one of that is controlled?stress rheology measurement under oscillatory strain amplitude sweep,the other is controlled?strain rheology measurement under steady stress sweep.The experimental results show that the storage modulus of the greases with tackifiers is decreased and the strain is increased,compared with the greases without tackifiers.The addi?tion of tackifiers results in the increase of viscous properties and the decrease of elastic properties of the lithium greases,so the lithium greases with tackifiers are more difficult to flow,and are easier to deform under stress and also easier to recover when stress disappears.Several kinds of tackifiers in study have different extent of influence on the lithium greases,the in?fluence of polymethacrylate is more obvious than that of the ethylene?propylene copolymer with low molecular weight.