特大型回转窑项目实施面临的问题与对策

从特大型回转窑项目实施面临的大件(轮带、大齿圈和筒体)运输、齿轮的承载能力等问题分析入手,提出了设计和适合于现场的制作方案;通过力学平衡实例解算,解决了回转窑用自定位滑履轴承设计的关键技术——滑履托瓦倾角的确定;通过齿轮变位系数选择与分配、螺旋角的选择,解决了常规模数回转窑齿轮承载能力小的问题;运用比照法对特大型回转窑的设计方案进行评估,得出结论:使用滑履轴承、多瓣组合大齿圈、现场组焊滑环、现场制作筒体、现场切削焊接坡口和垫板外圆,可以解决特大型回转窑项目实施的大件运输问题;通过对变位系数进行合理分配和采用斜齿轮传动,可以满足大功率传动要求;采用自定位滑履轴承,不但省去了挡轮装置,而且使滑履与滑环接触面自动吻合,可以避免热工制度改变和操作等原因造成的轮带和托轮不正常磨损。     

基于已建基础的滑履磨设计

根据已建滑履磨的基础形状和预留地脚螺栓孔位置实测数据,逆向设计滑履磨,对滑履磨筒体、滑履轴承、进出料装置等主要零部件进行了设计,确保与已建滑履磨基础安装配套;按照用户水泥粉磨生产线工艺要求,对磨机回转部件等内部结构进行了设计改进,满足了水泥粉磨生产工艺要求.     

Ф3.8×12.5m滑履磨润滑站的研制

由中信重机公司在１９９８年自行开发研制的３．８ ×１２．５ｍ多点啮合边缘传动滑履磨是国内首创。在结构上,该滑履磨的整个磨体由４个滑履轴承支撑,上轴承座的大小不影响中空轴的尺寸,这样就解决了传统水泥磨因结构限制而影响磨机的产量。但对润滑站的要求也随之提高,一台磨机需配４台润滑站,每台润滑站都有高低压两套供油系统,分别向磨机两端的四个滑履提供润滑和支撑,以保证整个磨机的正常工作。 高压供油系统在磨机启动或停止前后向滑履轴承输送高压油,使整个磨体浮起,并形成一定厚度的油膜,以减少启动力矩及停磨时避免因转…     

φ4.2×13 m滑履磨机修改设计

河南义煤集团水泥厂的5000t/d新型干法水泥生产线,其中的2台φ4.2×13m滑履磨机由成都建筑材料工业设计研究院设计,中信重型机械公司生产制造,该双滑履磨技术较为先进,为许多厂家所选用。在本次生产过程当中,根据实际工艺需求,对其磨内的原有结构进行了一些修改设计,现就有关改进的设计内容归纳如下。1磨机主要技术参数该磨机的主要技术参数见表1。2磨机结构特点该磨机主要由进料装置、滑履轴承、回转部分、表1φ4.2×13m滑履磨主要技术参数规格(mm)筒体内径筒体有效内径筒体内壁长度筒体有效长度工艺参数粉磨方式生产能力(t/h)出磨成品细度…     

干法球磨机磨内喷水冷却技术的分析与应用

针对干法球磨机滑履轴承托瓦在运转中因温度过高容易导致设备跳停、烧瓦等事故,对磨内喷水冷却技术进行了综合研究,并对其特点和应用情况进行了归纳总结。实际应用表明,该降温方式有效降低了滑履轴承托瓦温度以及出磨物料温度,避免了干法球磨机动力传递过程中的安全事故,为干法球磨机的设计提供了借鉴。     

特大型矿用磨机滑履轴承润滑系统解析

结合滑履轴承的结构和工作原理,详细介绍了特大型矿用磨机滑履轴承润滑系统的设计组成,并对系统的工作原理、参数选定、功能特点及安全保护等逐一进行了分析。实际应用表明,该系统很好地满足了特大型磨机滑履轴承的润滑要求,确保了磨机安全、可靠运行。     

滑履磨机试运转时所遇问题及解决措施

陕 西尧柏特种水泥厂2000t/d新型干法水泥生产线,其磨机选用由中信重型机械公司生产的2台4×13m双滑履磨,设计产量75t/h,研磨体最大装载量为180t,中心传动,主电机功率为2500kW,该双滑履磨技术较成熟,现为许多厂家所选用。滑履磨相对于中空轴磨,具有重量轻、加工工艺简单、加工时间短、价格便宜等优点。但在磨机试运转过程中出现一些问题,本文就其原因及处理方法作一介绍。1漏球运转时研磨体17小球有部分从出料装置漏出。漏球的原因是出料篦板的两块中心筛板在安装时不平整,有错位 ;二是出料篦板中的外篦板与二仓的非标环沟衬板之间没有…     

φ3.8×9m滑履磨筒体加工工艺

一、引言滑履磨是一种新型的水泥磨。具有结构简单、运行可靠、工作效率高和占地面积小等优点，在国外建材行业已广泛使用。随着在国内的应用越来越多，为制造业提出了新的课题。滑履磨与普通磨机的一个重要区别就是支承部分的位置与结构不同。普通磨机是支承在筒体两端的中空轴上，中空轴可以单独加工，而滑履磨则是支承在与筒体一体的滑环上，为保证滑环的精度、表面粗糙度和形位误差，最好的办法是整体加工。我公司1994年与丹麦史密斯公司合作生产的Ф3．8×9m滑履磨筒体如图1所示。该磨机是双滑环结构，其主要的加工部位、两处gb3970h。…     

干法球磨机滑履轴承降温技术研究与应用

针对干法球磨机在运转过程中滑履轴承托瓦温度过高,会引起烧瓦、传动不平稳等问题,以及非常严重的恶性事故,针对不同的降温技术进行综合论述,并对其特点及应用情况进行了归纳总结。通过实际应用,提出了针对干法球磨机滑履轴承不同情况下的有效降温技术,避免了干法球磨机动力传递过程中的安全事故,对干法球磨机寿命的提高起到了一定的促进作用,为干法球磨机的设计提供了借鉴。     

筒辊磨功耗因数的探究

运用模型推理、控制变量法和MATLAB编程方法,分别探讨了物料粒度、功率因数和滑履摩擦对磨机功耗的影响。导出理论状态下,物料钳角α≤2γ时,物料粒度对磨机功耗的影响较低;当筒体与磨辊比值k=2.1左右时,功耗最低;单位功耗与磨辊直径的1.5次方成正比。并且得出了主、副支承滑履方位角θ1、θ2与摩擦功耗的三维关系图。分析结果可为筒辊磨结构参数的优化提供参考,也为后续筒辊磨功耗试验提供依据。     

“双碳”目标下球磨机节能降耗技术研究进展

球磨机广泛应用于冶金矿山行业,磨矿作业的动力消耗与金属消耗较大,如何有效降低能耗与金属消耗是一项重要研究内容。主要从磨机自身结构改进、精确化装补球技术、耐磨材料制备技术三个方面进行综述。磨机自身结构改进主要包括以下措施:球磨机大型化、将边缘传动改为中心传动、将滑动轴承改为滚动轴承、改善研磨介质与衬板种类与形状。精确化装补球技术在我国矿山中应用广泛,均不同程度地降低了球磨机的电耗与球耗。耐磨材料制备技术主要围绕锰钢材料、铸铁材料、合金钢材料、双金属复合材料、磁性材料、橡胶材料的设计与制备进行了阐述,主要通过微合金化设计、热处理制度改进达到细化晶粒、转变组织的目的,提高材料的耐磨性,从而降低磨损率。      

采煤机导向滑靴的机械制造工艺优化

以矿井采煤机导向滑靴为研究对象,阐述了传统导向滑靴耐磨层打磨过程中,焊接材料贵、加工成本高、制造效率低等问题,从焊接材料和焊接方式上提出了制造工艺优化方案,并通过试验平台验证了方案的可行性。为煤矿机械部件制造工艺提供了有效的改进思路。     

立式辊磨机对菱镁矿磨矿及浮选效果的影响

立式辊磨机是一种集中碎、粉磨、快速烘干、高效选粉等工序为一体的高效节能环保型设备,具有结构 简单紧凑、工作可靠、流程简单、占地面积小等诸多优点。 针对丹东宽甸某菱镁矿,分别进行立式辊磨机与球磨机磨 矿—浮选试验,通过对比磨矿能耗、磨耗、磨矿产品粒度特性、矿浆中 Fe3+浓度等数据,并比较了药剂制度对闭路试验 精矿指标的差异。 结果表明:立式辊磨机磨矿的能耗仅为球磨机磨矿能耗的 17%左右,立式辊磨机的磨耗约为球磨 机磨耗的 6%左右,同时立式辊磨机磨矿产品中有利于浮选的中间粒级(0. 105~ 0. 045 mm 粒级)含量要比球磨机磨矿 高 2. 39 个百分点、立式辊磨机磨矿矿浆中的 Fe³⁺浓度也仅为球磨机磨矿矿浆的 17. 86%;通过闭路试验精矿指标对比 表明,使用立式辊磨机磨矿,可有效降低油酸钠与六偏磷酸钠用量,并降低精矿中 CaO 品位,提升精矿质量。     

球磨机提升条

球磨机是粉磨作业所需的重要设备,为了提高生产效率,延长提升条的使用寿命,需要选择合适的耐磨材料以及设计出合理的耐磨结构。本文根据两种生物耐磨特征,运用三维建模软件建立了光滑、横向条纹、纵向条纹、凸包的仿生结构特征提升条的球磨机模型。通过数值模拟与磨矿实验,统计了磨矿过程中4种不同表面特征提升条的应力分布、累积力、微观磨损形貌等信息,结果表明具有仿生结构的提升条能够有效的缓释提升条在磨矿时的等效应力,降低了提升条的磨损消耗,对比发现横向条纹仿生结构在4种提升条中的耐磨性和磨矿效果最佳。     

煤矿大型滑动轴承刮研实践

阐述大型滑动轴承维护的步骤与方法:首先应合理确定最初配合间隙及最大磨损间隙,轴承在运转中不断磨损,此时需要对滑动轴承间隙进行调整,当顶间隙超过极限间隙数值时,需要刮研下瓦。在此基础上,介绍了义煤集团公司千秋煤矿在解决轴承持续磨损方面的经验。     

DEM modelling of liner evolution and its influence on grinding rate in ball mills

Wear of grinding mill liners and lifters plays a major role in the overall efficiency and economics of mineral processing. Change in the shape of lifters as they wear has a significant influence on grinding efficiency, and the annual cost of maintenance and mill down-time depends on the life of both liners and lifters. The Discrete Element Method (DEM) is a computational method for simulating the dynamics of particle processes. This paper presents an analysis of 3D simulation of a grinding mill carried out using the EDEM software package customised to predict the rate of wear of lifter geometry and to enable progressive updating of worn lifter geometry profiles. A simplified breakage rate model is developed as a tool to correlate liner profile to mill performance.The combination of the prediction of liner profile and grinding rate shows promise to provide a powerful tool for advanced mill liner design – providing a means to balance liner life and mill performance over the life of the liner at the liner design stage.     

An experimental investigation of the effects of operating parameters on the wear of lifters in tumbling mills

Lifters are usually used with mill liners to extend their life and to enhance the grinding and crushing efficiency. Although the lifters are durable wear parts but they will gradually worn and consequently their dimensions change during the course of operation. These changes in dimensions have a significant influence on the overall economic performance of the mills. Therefore, it is useful to know the relationship between the mill operation and the lifter profile, and the influence of lifter wear on the change in lifter profile. In this work, a laboratory mill which is capable of producing the required impact and abrasion grinding was operated both wet and dry. Many factors were varied such as: velocity, charge, ore size and different material for the lifters. Also the wear rate on the top and face of lifters are compared in the different conditions. It is found that the mill charge and the mill speed significantly affect the wear rate. Also, the results showed how size distribution affects the wear rate. The results can be interpreted in terms of the wear process in industrial scale mills over different operating conditions. The experimental results provide the possibility of including the lifter wear in optimising mill performance.     

Discrete element method (DEM) modelling of evolving mill liner profiles due to wear. Part II. Industrial case study

The wear of tumbling mill liners influences the load behaviour and consequently the performance and efficiency of tumbling mills. The ability to accurately predict the evolving mill liner profile due to wear is therefore of great economic significance since it can be used to determine the optimal initial lifter design for a particular operation. In this paper, we use the discrete element method (DEM) to simulate the load behaviour and predict the wear of two different liners used in industrial mills for the grinding of coal in dry conditions. Our simulated results are compared to industrial measurements in both cases. A good agreement is found between those measurements. Moreover a quick empirical equation is derived for a particular lifter in order to predict the wear without using the DEM.     

Is media shape important for grinding performance in stirred mills?

Models for understanding the basic concepts of fine grinding and how they apply to the design of stirred media mills have not yet matured. While spherical media in tower mills has previously been studied, real grinding media shape in stirred mills can range from spherical (steel/ceramic balls) to highly non-spherical (sand or slag) resulting in very different media and grinding dynamics. Handling the contact mechanics of non-spherical particles is a challenge for numerical models, and very few studies dealing with non-spherical particle shape exist in the literature. Discrete Element Method (DEM) simulations of dry media flow in a pilot-scale tower mill are performed for four cases with different shaped grinding media, in order to understand how flow and energy utilisation within a stirred mill depend on media shape. Differences in media transport, stress distribution, energy dissipation, and liner wear were observed in the tower mill for the spherical and non-spherical cases. A significant departure from sphericity of the media leads to strong dilation of the bed, reduced bulk density, and a reduction in active volume and collisional power levels leading to a reduction in power draw for the mill. In addition, highly non-spherical media tend to pack tightly near the mill walls forming a near solid layer around the inside of the mill shell which results in poorer transport and mixing, as well as increased wear rates on the screw impeller. Grinding performance in stirred mills appears to deteriorate strongly when using highly non-spherical media.