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131.
This work aims to characterize vibration behavior of roller bearings as a function of lubricant viscosity. Experimental tests were performed in NU205 roller bearings, lubricated with mineral oil of three different viscosity grades (ISO 10, 32 and 68). The mechanical vibration was determined through the processing and analysis of bearing radial vibration data, obtained from each of the lubrication conditions, during 2 h of test run for temperature stabilization and under several bearing shaft speeds. The applied radial load was 10% of the bearing nominal load. Through root mean square (RMS) analysis of the vibration signals, it was possible to identify specific frequency bands modulated by the change in lubricant viscosity, which was related to change in oil film thickness. 相似文献
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基于接触强度的最小尺寸凸轮机构设计 总被引:7,自引:4,他引:7
本文从凸轮副接触应力σH(r,φ)的表达式出发,构造起其相当函数J(r,φ)的三维立体图象,并借助此立体图象对最佳滚子半径r*的客观存在性给予了清晰、直观的几何解释和论证,最后给出了求解最佳滚子半径r*的通用有效算法。 相似文献
134.
解决皮带输送机跑偏问题的方法 总被引:2,自引:0,他引:2
从使用者角度出发,通过对带式输送杌在使用过程中出现胶带跑偏原因的分析,提出了胶带跑偏后的几种解决方法,这几种方法操作简便,使用工具简单,不受场地限制,经济实用。 相似文献
135.
《Advanced Powder Technology》2020,31(11):4445-4456
In this work, the screening process of an industrial-scale roller screen was simulated based on the validated discrete element method (DEM). The effects of the feed rate, rotational speed of rollers, inclination angle of screen deck and the cohesion force between wet particles on the screening process were investigated. The results show that screening efficiency decreases with the increase of feed rate, which remains above 0.80 when the feed rate is less than 700 kg/s. The optimal values of rotational speed and inclination for high efficiency are 100 r/min and 6°, respectively. Working parameters have a significant effect on both the passing percentage and the average velocity of different size fractions. Hence, reasonable working parameters should be adopted to avoid the accumulation of particles on the deck. Moreover, both particle shape and cohesion force have little effect on the screening processes of the roller screen. 相似文献
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《The Journal of Strategic Information Systems》2020,29(2):101613
Recent years have seen heightened interest in how information technologies (IT) are changing the nature of work in strategy and in the work of strategists. This paper highlights four ‘modes of open strategizing’ which represent the digital work activities of strategists, who in our case are top managers involved in developing and implementing a new five-year strategy at a large professional association. Top managers adopted an open strategy approach and included their organizational community in shaping a future direction for the professional association. Whilst IT-enabled openness in strategy has received significant interest recently, few studies have focused on the specific (digital) work practices of strategists and subsequently connected this to notable outcomes such as organizational transformation. We therefore respond to this by connecting the four outlined modes we identify to show realized strategic outcomes of digital work and how it can transform organizations. 相似文献
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以双列调心滚子轴承为例,从理论上分析预紧滚动轴承径向工作游隙的影响因素以及工作游隙对轴承使用寿命的影响,并给出轴承预紧前最佳原始游隙的计算公式.实践证明这种方法可以保证轴承在具体的工作条件下处于最佳的工作游隙状态,达到最长的使用寿命. 相似文献
140.
滚子链传动振动特性的研究 总被引:5,自引:0,他引:5
提出了滚子链传动的横向振动新模型,依据新模型导出了滚子链传动时横向动力响应的表达式 相似文献