共查询到19条相似文献,搜索用时 187 毫秒
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针对圆锥滚子斜置贯穿式超精研凸度的变化和影响因素难以掌握的问题,介绍了斜置贯穿式超精研的工作机理,分析了滚子-油石接触的几何特征,提出和建立了滚子凸度修形仿真分析的原理、方法和几何模型,给出了仿真分析流程,并对凸度影响因素进行了仿真分析。结果表明:滚子斜置角主要影响凸度量大小和凸度形状,滚子倾斜角主要影响凸度对称性;与正置贯穿式超精研相比,斜置式可以大幅提高凸度量,且其凸度形状两端区域更陡峭,斜置角取值适当时凸度形状比较接近对数凸度曲线;油石厚度越大,凸度量越大;油石磨除滚子材料能力越强,凸度量越大,且被超精区域逐渐向中部集中。 相似文献
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提出圆锥滚子凸度贯穿式超精研修形加工的一种新型的锥柱匹配的导辊配置方式,其后导辊是圆柱形形面,可通用于不同型号的滚子;其前导辊采用匹配的专用螺旋锥形形面。对锥柱匹配导辊配置方式的滚子姿态进行简化分析表明,这是一种具有特定滚子姿态的斜置贯穿式超精研,可以获得凸度。依据共轭曲面原理建立斜置贯穿式超精研导辊的理想形面方程,通过数值计算分析锥柱匹配导辊形面和相应滚子姿态问题,结果表明,一般斜置贯穿式超精研前后导辊理想形面的轴向截形均为相对于导辊轴线倾斜的轻微内凹曲线,但存在特定的滚子姿态,可以使后导辊形面曲线不倾斜而只有轻微内凹;锥柱匹配导辊配置方式中,后导辊的圆柱面是近似形面,但其形状误差很小,一般不超过4 μm,对滚子的支撑稳定性影响不大。给出了锥柱匹配导辊配置方式中圆柱导辊形状误差、锥形导辊形面参数以及相应滚子姿态参数的精确计算方法。 相似文献
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滚子凸度超精研机床是以贯穿方式对圆柱或圆锥滚子的表面进行加工 ,不仅效率高 ,能很好地改善工件的粗糙度、波纹度和圆度 ,而且在滚子纵向形成微量凸度 ,使装配后的轴承能明显地减少或消除滚子边缘应力集中 ,减少温升 ,有利润滑 ,从而提高轴承的使用寿命 1~ 2倍。在该机床上最多可用 8块油石同时对滚子进行超精 ,8块油石采用 8个独立气缸提供压力。控制这些气缸的气动系统具有加压冲击小、断电后自动卸压等特点 ,能较好满足超精工艺要求。 该机床气动系统的工作原理如图 1所示。气动系统的最大工作压力为 0 .6MPa ,进入机床的压图 1… 相似文献
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滚子轴承滚道超精研机是我公司为适应客户对有凸度滚道超精研的需要,于近年来开发出的新型机床.新机型设计采用油石大往复小振荡技术,伺服电机驱动油石座滑板进行大往复运动,油石振荡头采用静压轴承的结构实现油石的振荡.即采用改变窄油石在滚道宽度内的往复速度和油石振荡频率,来实现有凸度滚道的超精研. 相似文献
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在经过改装的3M6312型四工位超精研机上,采用无心纵向进给贯穿式超精197726轴承的圆锥滚子,一次超精研达到成品滚子的各项技术要求。文中介绍了超精研规范和油石的选用原则,并以本厂工艺和引进的日本工艺作了对比。附图5幅,表1个。 相似文献
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在介绍一般超精研工作方式与工作原理的基础上,以深沟球轴承套圈沟道超精研和无心贯穿式圆锥滚子超精研为代表,通过与一般超精研的对比,探讨了滚动轴承超精研工艺的特殊性。一般超精研油石与工件之间为面接触,而滚动轴承的多种超精研方式中,油石与工件之间为非面接触,工艺特性更加复杂。对于这类特殊的超精研工艺,有必要开展深入系统的研究,并提出了进一步研究的主要问题。 相似文献
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传统认为圆锥滚子贯穿式超精中,超精导辊螺旋面全长保持一个工作角度,即导辊单角度超精时,滚子的上素线应保持水平状态。分析认为,上素线保持水平状态不是滚子的理想姿态,理想姿态是小端略高的状态,并分析滚子的凸度超精加工机理和影响凸度对称性及凸度量大小的因素。 相似文献
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根据三辊行星轧机的运动规律和轧辊设计原理,利用坐标变换的方法,建立起既有倾斜角β又有偏转角α的空间轧辊模型,研究了三辊行星轧机轧辊建模和定位的方法,确定了轧辊和轧件接触点计算的方法和轧件模型,在此基础上建立了三辊行星轧制空间模型. 相似文献
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Damage caused by particles within rolling/sliding contacts can severely reduce the operational life of machinery such as roller bearings, gears and pumps.Abrasive wear of spherical roller thrust bearings has been studied using a stylus apparatus and scanning electron microscopy (SEM). Both a standard bearing and a bearing with rollers coated with metal mixed amorphous carbon (Me-C:H) were studied. The SEM measurements were performed systematically across the contact surfaces so that surfaces with gradually different contact situations could be examined. These measurements were compared to the measured wear depth of the components of the roller bearing. Also, the calculated contact conditions in terms of creep, contact size and surface separation have been related to the observed wear pattern at various locations.To attempt to understand the wear behaviour of the bearing with coated rollers, the coating as well as the material content of the surfaces were examined using both SEM and energy dispersive X-ray spectrometry (EDS). This revealed that the coating did not flake off but rather was scratched off.It is possible to link the abrasive wear behaviour to the contact conditions. It is crucial to understand this relationship when building a simulation model of abrasive wear. 相似文献
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滚子偏斜对高速滚子轴承的寿命有显著影响。文中分析了在直母线和对数修形母线两种母线形式下,GCr15圆锥滚子和Si3N4圆锥滚子无偏斜、向小端偏斜及向大端偏斜三种情况时与GCr15滚道接触的应力分布情况。结果表明,对GCr15滚子或Si3N4滚子,一旦出现滚子偏斜,其接触应力和Mises应力值将显著增加,疲劳寿命大大降低,但修形后偏斜时的应力值要小于修形前。由于Si3N4的弹性模量大于GCr15的弹性模量,同时泊松比小于GCr15的泊松比,修形前后Si3N4滚子的应力值都高于GCr15滚子的应力值,疲劳源的深度也比GCr15滚子的大。 相似文献
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《Wear》1987,120(1):81-99
Simulation of roller guide wear in rod or wire rolling mills has been performed in a high temperature test rig where the specimen rollers are in intermittent contact with the periphery of a heated rotating steel disc.By varying the time in contact during each cycle and deliberately superimposing a sliding component on the rolling contact, three components of guide roller wear were separated and quantified. The dominant component is wear due to sliding at the contact surface during rolling, followed by the isolated contribution from absolute rolling, while wear during roller acceleration is of less importance.Surface studies and the observed linear increase in wear vs. number of test cycles together with the linear increase in wear rate with normal force clearly show that abrasion by disc oxides is the dominant wear mechanism at elevated temperatures. The influence of disc temperature on the operating wear mechanisms as well as the resulting wear are also evaluated.A quantitative classification of four guide roller materials, a high chromium tool steel, two grades of high chromium cast iron and a cermet, has also been made. The hard cermet, containing about 50 vol.% titanium carbides, proved to be the outstanding material in roller guide applications. 相似文献