超临速球磨机导向机构设计分析及磨矿介质运动学规律研究

【作者】 刘道玉；

【导师】 迟毅林；

【作者基本信息】 昆明理工大学 ， 机械设计及理论， 2005， 硕士

【摘要】 在磨矿作业过程中,球磨机的生产能力随球磨机转速的增加而增加,提高球磨机转速,可显著地提高球磨机生产能力,但是当常规球磨机的转速达到或超过某一值时,其磨矿介质和矿石将发生离心运动,磨矿能力不但不随转速的进一步增加而增加,反而出现几乎不能磨矿的现象,这时球磨机的转速就是临界转速。超临速球磨机作为一种新型的磨矿设备,其磨矿机理和常规球磨机有很大的不同,它突破了常规球磨机只能在临界转速以下工作的限制,以超过临界转速进行磨矿作业,磨矿效率大大提高。 超临速球磨机筒体内采用导向机构改变了常规球磨机内被重力和离心力控制的磨矿介质和矿石的运动轨迹,使矿石受到高速和最大限度的冲击和磨剥,磨矿效率和磨矿速度大大提高,从而达到球磨机小型化、生产能力大型化的目标。目前国内外在超临速磨矿设备和理论方面的研究还不多见,且大多是从工艺上进行的研究,超临速球磨机的设计制造缺乏新的理论依据,还不能广泛应用于工业生产实际。 本论文对超临速球磨机的结构组成、特点进行了阐述,对其导向机构进行了合理的设计,并对整机进行了三维建模。在有限元理论分析的基础上,对导向机构建立了符合实际工况的理论模型、边界条件等,用ANSYS软件进行了有限元仿真分析,得到了导向机构的结构变形和应力、应变分布情况,分析结果和实际情况相符,总结出了一些很有学术和应用价值的结论。 针对超临速球磨机磨矿介质运动的三个阶段:圆周运动阶段、沿导向板滑落阶段、抛物线冲击矿石阶段,对超临速球磨机磨矿介质运动规律进行了研究,得出了超临速球磨机磨矿介质的运动轨迹方程、对矿石的冲击速度、冲击力公式和冲击次数等,为进一步探讨磨矿介质对矿石的冲击效果而进行运动仿真和试验分析奠定了理论基础。最后为该课题的进一步研究方向提出了一些有益的建议。 本论文所运用的研究方法和得出的结论对超临速球磨机工业化设计能起到积极的推动作用。更多还原

【Abstract】 In the process of grinding ores, the productive capacity of the ball mill will be increased with the increment of the rotation speed. But the centrifugal motion of balls and ores will occur when the rotation speed of the ball mill reaches or exceeds the special value, and the productive capacity can’t be increased, even that the ordinary ball mill can hardly grind ores. The special value is named as critical rotation speed of the ball mill. Ultracritical rotation speed ball mill(URSBM)is a new kind of equipment for grinding ores, it is different from ordinary ball mill in the principle of grinding ores. URSBM has broken the limit of critical rotation speed, and it can grind ores by exceeding critical rotation speed, so its efficiency of grinding ores is increased.The centrifugal motion state of the balls and ores in the URSBM is changed by guidance device equipped in the URSBM, and the balls and ores are forced to move in parabola locus, so the ores are crashed and milled acutely, and the productive capacity of the URSBM is increased remarkably. The developing objective that the small-scale ball mill has large-scale productive capacity is attained. Now, the researches on URSBM and its principle of grinding ores are not enough, and most of which are researches on process of grinding ores. The industrialization design of URSBM lacks theory basis. Therefore, the URSBM can’t apply to the industrial production.This paper introduces the structure and characteristics of URSBM, designs the guidance device of it reasonably, and establishes the three-dimensional model of it. Basing on the theory analysis of finite element, the author has constructed the theory model, boundary conditions of guidance device, and analyzed it with ANSYS software. The guidance device’s structural deformation, stress and strain distribution are found. The results of simulation analysis are fit for practice. And the author gets some conclusions which have academic and applied value.According to that the ball mediums in the URSBM go through three steps: uniform circumference motion, motion on the surface of guidance arc plate and parabola motion, the author studies the kinematics regularity of the ball mediums. The parabola equation, the formula of impact velocity, impact forces of the ball mediums and impact frequency are extracted. Therefore, more researches on motive simulationof ball mediums striking ores and test analysis have theory foundation. Besides, this paper has given some useful advice on the task in the future.The new thought this paper presents and the new study method this paper uses must accelerate the process of URSBM industrialization design.更多还原