转盘卷取机活动支承的结构改进及分析

对转盘卷取机一号活动支承底座结构进行改进,采用ANSYS有限元软件对改进前后的结构进行分析,计算结果表明,改进后的活动支承底座刚度与原有结构接近。实际应用表明该结构能够达到减少卷取机卷筒震颤的效果,同时改进后的结构也能满足飞剪锁紧缸拆卸方便的需求。     

掘进机回转支承常见故障分析及预防措施研究

为延长掘进机回转支承的使用寿命,基于掘进机回转支承在掘进机中的重要性以及其工作环境的复杂性,结合掘进机回转支承的主要结构形式,分析了影响掘进机回转支承运行寿命的主要因素,并提出了一些预防掘进机回转支承故障的措施.实际应用结果表明,通过综合应用这些措施,能显著减少掘进机回转支承的故障率,有效延长回转支承的应用寿命,更好地...     

中厚板轧机支承辊用轴承的修复与结构改进

引进了二手轧机支承辊四列圆锥滚子轴承经修复后达到了标准要求 ,但寿命很短 ,为此用“滚动轴承极限设计方法”对该轴承进行了设计改进 ,使其额定动载荷和额定寿命均有较大提高 ,并在结构上采用了半密封结构 ,改善了轴承的润滑条件 ,取得较为满意的使用效果。附图 1幅。     

浅谈静压轴承的特点、设计及修复

目前,许多机床的磨头支承结构采用了静压支承,静压支承具有几何精度高,波纹小,维修性方便,寿命长等优点.用于加工硬质合金刀片的机床,由于对以上要求都较高,故改造的成型专用磨床,其前后轴承和止推轴承都是小孔节流的静压轴承.本人根据多年的实践经验,在此介绍小孔节流的静压轴承的特点、计算、维修及修复.     

搅拌轴支承结构的改进

化工设备中的搅拌装置的性能、寿命往往决定于搅拌轴及其支承的可靠性.为此,介绍一种可靠性高的新型搅拌轴支承结构,该结构安装容易,特别适宜搅拌轴下端和封头底端较近的情形.     

一种先进的轴承支承结构

简要介绍进口的柴油加氢精制装置反应进料泵,FACCA400 M02B3型电机轴承支承结构形式和密封结构及性能特点.     

超精研机静压支承的改进

VMUC100A(100D)轴承沟遂道自动超精研机，采用机械压轴式无心静压支承夹具。此设备一般提供胶木体和金属体静用支承。在使用中胶木体支承刚性差异“跑点”，金属体支承虽不“跑点”，但易产生套圈表面来重划伤。为了解决     

轴支承结构设计准则（八）

轴支承结构设计准则（八）杨文彬（南京化工大学）１引言旋转运动的轴必须由至少两只相距一定距离的滚动（或滑动）轴承来支承，旋转轴的运行性能。支承状况及质量密切相关，对旋转轴支承状况和质量有决定性影响的不仅是轴承本身，而且包括轴承周围的支承结构设计。滚动轴...     

平面滑动回转支承设计方法

介绍了一种以高分子聚合物材料为基础的新型滑动回转支承。说明了与普通滚动回转支承相比,此滑动回转支承具有结构简单紧凑、加工工艺简单、价格成本低廉、安装维护方便、承载能力大、使用寿命长等优点。对滑动回转支承进行了理论上的外载荷(倾覆力矩、轴向载荷、径向载荷)分析,由此确定了滑动回转支承外载荷与结构尺寸之间的数量关系,并由此提出滑动回转支承的设计方法,确定了滑动回转支承的主要结构尺寸。最后,对滑动回转支承与滚动回转支承进行比较分析,进一步说明其具有功耗低、性价比高、成本低、应用范围广等优点。     

多用木工机床刀轴支承结构的设计与分析

随着高科技技术的发展，现代新型节能优化设计应用于工业中的各个领域，多用木工机床的诞生填补了老式木工机床刀轴支承结构受力不均，使用寿命低的特点，通过对其优化设计，提高了生产效率，降低了经济成本。本文主要围绕对多台木工机床刀轴支承结构进行工况分析，和改进措施对其结构优化设计，进一步来说明科技创新带给人们的方便，从而保证了木工机床的安全生产，创造更多的经济效益。     

A Comparative Study of Static and Dynamic Characteristics of Parabolic and Plane Inclined Slider Bearings Lubricated with MHD Couple Stress Fluids

In this article the couple stress effects on the static and dynamic characteristics of parabolic and plane inclined slider bearings in the presence of an applied magnetic field with squeeze action is analyzed theoretically. The modified magnetohydrodynamic (MHD) couple stress Reynolds equation is derived. The closed-form solution for the film pressure of parabolic and inclined plane slider bearings is obtained and used to study the MHD couple stress static and dynamic characteristics of these bearings. The results predict a higher steady load-carrying capacity, dynamic stiffness, and damping coefficient for the bearings lubricated with MHD couple stress fluid than the corresponding Newtonian case. It is observed that the parabolic-shaped slider bearings provide greater steady load-carrying capacity, dynamic stiffness, and damping coefficients compared to the plane inclined slider bearings.     

水泥球磨机调心滚子轴承接触应力和寿命分析

介绍了球磨机小齿轮轴两端调心滚子轴承载荷的计算方法,建立Romax轴系仿真模型,分析了径向力、齿轮推力、温度对轴承接触应力和寿命的影响,结果表明:随径向力增大,轴承最大接触应力增大,寿命减小;随齿轮推力增大,游动端轴承的接触应力和寿命几乎无变化,固定端轴承列1和列2接触应力变化趋势不同,0～225 kN,列1呈减小趋势...     

Experimental evaluation of the stress distribution on the outer surface of the outer race of conventional and double‐decker high‐precision bearings

Experimental investigations have been carried out on the stress distribution on the outer surface of the outer race of conventional and double‐decker high‐precision bearings (DDHPBs). The investigations, in general, indicate that the overall level of stress variation on conventional bearings in various modes of loading under static conditions is greater than that of DDHPBs having an identical inner bore. The cyclic stress levels have been found to be higher for the outer race of conventional bearings compared to that of DDHPBs. Also, the frequency of stress cycles on the outer race of conventional bearings is greater than that of DDHPBs. A comparison of the stress distribution pattern indicates that, under identical loads, the ratio of deflection to indentation on the elements of DDHPBs and conventional bearings is less than unity. Also, under identical operating conditions, the ratio of stresses due to centrifugal forces on the elements of DDHPBs and conventional bearings of the same bore and outer diameter is less than unity. It is concluded that the life of DDHPBs as compared to conventional bearings should be longer under identical operating conditions.     

钢制和陶瓷圆柱滚子轴承高速性能的有限元分析

在高速圆柱滚子轴承理论研究的基础上,对普通钢制轴承和陶瓷轴承进行有限元分析,研究了转速对接触应力和等效应力的影响.结果表明,高速轴承的疲劳寿命主要取决于滚动体作用于外圈的离心力,减小滚动体离心力是提高此类轴承寿命的最有效途径;在中、低速时,钢轴承的寿命和可靠性均好于陶瓷轴承.但当转速达到高速时,陶瓷轴承在寿命方面显示出更大的优势.为陶瓷轴承的设计与应用提供参考.     

Lubrication of a narrow porous journal bearing with a couple stress fluid

This paper describes a theoretical investigation of the rheological effects of couple stress fluids on the performance of narrow porous journal bearings. A most general modified Reynolds equation is derived for narrow porous journal bearings using the Stokes constitutive equations for couple stress fluids. The fluid in the film region and in the porous region has been modelled as a couple stress fluid. The analysis takes into account velocity slip at the porous interface using the Beavers‐Joseph criterion. A closed‐form expression for field pressure is obtained for narrow journal bearings. Eigen‐type expressions for field variations are obtained. The dimensionless load‐carrying capacity, attitude angle, and coefficient of friction are presented for different operating parameters. It is observed that narrow porous journal bearings with couple stress fluids as lubricant show a significant increase in load‐carrying capacity with reduced coefficient of friction as compared to the Newtonian case. The present study predicts the effects of the percolation of polar additives (microstructures) into the porous matrix on the bearing performance.     

A study of optimum load-bearing capacity for slider bearings lubricated with couple stress fluids in magnetic field

A theoretical study of slider bearings in general form is presented, considering the lubricant to be an isothermal, incompressible electrically conducting couple stress fluid in the presence of a uniform magnetic field. An expression for a modified Reynolds equation is derived in order to obtain pressure gradient in terms of inlet–outlet (IO) film height ratio (simply IO film ratio) of slider bearings. As a special case, a study of the IO film ratio of four particular types of slider bearings is analysed. For the study of optimum load capacity, three-dimensional geometry has been assumed in order to consider side flow. Values of maximum load capacity for various values of couple stress and magnetic parameters, and the corresponding IO film ratio of the four bearings are obtained numerically, and a comparative study of these values has been presented. A comparative study of optimum load-carrying capacity for finite and infinite slider bearings has also been made. It is observed that both the values of maximum load capacity and the corresponding IO film ratio depend on couple stress and magnetic parameters and the shape of bearings conjointly. The present results are also compared with the similar available data in Newtonian cases.     

基于BP神经网络和有限元分析的深穴圆柱滚子的优化设计

针对直素线圆柱滚子轴承在工作中滚子端部出现应力集中,降低轴承接触疲劳寿命的问题,采用了深穴圆柱滚子。结构合理的深穴圆柱滚子轴承可以有效改善普通直素线滚子轴承受载后滚子两端的边缘应力集中现象。采用ABAQUS有限元分析软件对深穴圆柱滚子轴承进行了三维接触有限元分析,应用BP神经网络对滚子深穴结构进行了优化,优化后滚子两端部位的边缘应力集中明显减小,轴承的接触疲劳寿命和承载能力得到提高。     

低速滚动轴承故障诊断方法研究

低速滚动轴承结构和工作条件特殊,故障机理复杂,诊断难度较大。本文根据低速滚动轴承的故障特性,提出了利用应力波与小波分析进行低速滚动轴承故障诊断的方法。首先以低速运转Cooper轴承系列01B65 EX滚子轴承为例,建立了完好和故障低速滚动轴承的三维整体接触计算模型,运用有限元软件对其进行了比较全面、精确的分析,计算出外圈故障模型的最大应力和应变及各元件之间的接触应力,将发生故障前后的外圈外表面应力应变分布规律以及接触应力分布规律进行比较。然后在应力波实验分析的基础上,选择db6母小波、尺度j=4对实验所采集的数据信号进行小波变换,成功提取了外圈模拟故障的应力波信号特征频率。     

异形支承圆柱滚子轴承结构优化

使用传统弹性接触理论校核某汽车变速箱用异形支承圆柱滚子轴承接触应力,结果满足设计要求,但使用中因出现边缘应力集中而失效。建立有限元模型进行分析,认为出现边缘应力集中的原因为外圈与滚子边缘接触位置有严重折弯变形,通过在轴承外圈上增加0.2 mm过渡阶梯的改进措施,折弯变形减小了50%。经耐久性试验验证,优化后轴承满足使用要求。     

基于接触应力的圆柱滚子轴承疲劳寿命分析

首先介绍了圆柱滚子轴承疲劳寿命的经典理论计算方法.然后运用Hertz接触应力理论计算出圆柱滚子轴承的最大接触应力,结合三参数幂函数公式确立疲劳寿命曲线方程计算出轴承的疲劳寿命值.通过改变轴承滚子数目、径向力大小以及径向游隙等参数,将基于接触应力得到的疲劳寿命结果与经典理论结果进行比较,证明了该方法的合理性.并分析了在考虑离心力作用下高速圆柱滚子轴承疲劳寿命与转速之间的关系.