The flowability of ground powders and the comminuting mechanism of mills

The ground powders with the same particle size distribulion and the sanw mean particle diameter were prepared by five different types of mills. The flowability index (FI) and the particle shape indices, namely. Wadell‘s working sphericity ψw and circularity ψc , of five kinds of test powders were nwasured. The effect of the comminuting mechanisms on the flowability of ground powders was investigated, and the relationship between the flowability of ground powders and the partticle shape indices was analyzed. The experimental restdts show that the ground turn,tiers obtained by collision have irregular particle shapes and smooth surfaces, showing a high flowability. On the other hand, though the particle obtained by grinding is close to a spherical particle, but it has a rugged suttee, and shows a bad flowability. Furthermore, the flowability index is more corrdated with the circularity titan the working sphericity is. This means that the surface roughness is more effective, in determining the flowability of powders than the roundtwss is.     

我国锤片粉碎机的现状和提高方向

本文简要地阐述了锤片粉碎机的工作原理和影响粉碎效率的因素,讨论了主要技术参数对粉碎机性能的影响。介绍了我国锤片粉碎机发展过程,特别是较前有重大突破的七十年代末期和八十年代初期粉碎机的研制情况、推出的产品、达到的水平和系列化工作的情况。并对锤片粉碎机的制造、安装、操作、管理、工艺设计、工艺流程、吸风配备、传动、自动化以及进一步研完粉碎理论改进机器结构等十个方面提出了个人看法和改进意见。     

新型冲击式超细粉碎机研究

研制的新型立式高速冲击超细粉碎样机，粉碎石灰石的产品平均粒径为2．34μm．粉碎3～8组奠氏硬度的物料时，其平均粒径均在25μm以下。试验结果表明：动态机械性能和粉碎、分级效率等指标均满足要求；能适应多种物料超细粉碎，粉碎物料的平均粒径超过了日本MVM型机的平均粒径。     

新型塑料粉碎机

瑞典乐必得塑料粉碎机制造公司推出新型塑料粉碎机系列．从根本上简化了清洁和维护程序，降低了人工费用，机器停工期减少了50％，还可通过简单操作来检测机器是否清洁，以防止在更换原料和颜色时产生污染。     

基于TRIZ原理的粉碎机锤片结构问题解决方案

利用TRIZ理论中的冲突解决理论和物质-场分析与标准解,提出几种防止锤片磨损、破坏,以及提高粉碎效率、降低粉碎能耗的方案,为设计锤片新结构提供了依据.     

双自由度共振制样粉碎机的设计

利用双自由反共振原理设计的新型制样粉碎机,与传统单自由度系统制样粉碎机相比,具有激振电机不振动、没有陀螺效应、提高激振电机的使用寿命、改善工作环境、达到防震降噪目的的特点。同时由于激振能量大部分被振动料钵吸收,在相同情况下,电机功率由原来的1．1kW降至0．5kW,达到了降低能量的效果。     

涡轮分级机中粒子粉碎效应研究

介绍了一种适合超细粒子分级的高效精密空气分级设备－ＳＷ型卧式涡轮分级机，分析了分级流场的特性，从理论和实验两方面对分级机的粉碎效应进行了研究。     

Research on Selective Shredding of Wasted Printed Circuit Boards

Electronic scrap, especially wasted printed circuit boards (PCBs), is regarded as an environmental challenge. At present, the physical separation is thought to be the environmental friendly and economical method of treating and reutilizing electronic waste. An effective liberation of metals from non-metallic components is a crucial step towards mechanical separation and recycling of wasted PCBs. In this paper, the selective shredding theory and mechanics characteristics of wasted PCBs were analyzed, and the shredded experiments of wasted PCBs by hammer mill were investigated. The result shows that the selective shredding exists in the wasted PCBs shredded process by hammer mill. The shredding velocity of non-metallic components is far greater than that of metals in the wasted PCBs shredding, which makes the metals concentrate in the coarserfr action. And the impact force of hammer mill is superior to metai liberation from non-metallic components, a satisfied metal liberation degree can be achieved in the wasted PCBs shredding by hammer mill.     

循环式气力输送装置在饲料粉碎机上的应用

本文针对饲料粉碎机粉碎后的物料比重轻、颗粒细不易分离,含尘浓度大的空气排入大气中,既浪费饲料,又污染环境等问题,将循环式气力输送装置应用在饲料粉碎机除尘,实践证明可提高分离与除尘效率,效果显著.     

饲料粉碎机的吸风与气力输送效果试验

本文通过生产实际和测定,认为对饲料粉碎机排料时进行吸风,再行机械提升,或采用气力输送,均可提高粉碎机的生产率。气力输送在提高生产率,改善出机物料的物理状态和设备工作状态方面,优于机械输送加吸风,但一般只适用于先粉碎后配料的生产工艺。