浅谈鄂式破碎机设计中的啮角分析

通过对颚式破碎机动颚运动轨迹的分析,提出传统的颚式破碎机的啮角设计概念有很大的局限性,认为它没有真实地反映颚式破碎机的工作状况,进而提出啮角设计的新概念——工态啮角。     

破碎革新

在过去的100年间，破碎实践中有许多重要的改变，但相对来说，发生在岩矿粉碎破碎机中的基础性变革却很少。第一台颚式和旋回式破碎机起源于19世纪中期和后期。为了满足现今工业大产量的需求，开发的大型设计几乎都基于原来概念上的颚式和旋回式破碎机。然而，过去采用这些设计的工作人员都经历过在相对短期运行后常由于出现过多的润滑问题而致使营筒组机械疲劳的故障，如旋回式破碎机模臂梁的折断、联结松动、驱动轴出问题、颚式破碎机机架的断裂、机底部分的疲损。甚至是先进的技术也能产生出重大的故障，比如：电脑程控系统在一定条件下…     

基于ug的颚式破碎机的运动仿真

通过UG软件对颚式破碎机进行建模及运动仿真,介绍如何模拟动颚的往复摆动,分析动颚的摆角、速度、加速度,获得机构的行程速比系数。     

大破碎比颚式破碎机及对破碎工艺流程的变革

介绍了新型破碎设备--外动颚大破碎比颚式破碎机及该系列产品的技术参数、性能特点;可用一段大破碎比破碎机取代传统流程中的两段或三段破碎,新型破碎设备的研制成功带来了破碎工艺的变革。     

颚式破碎机惯性力平衡优化

颚式破碎机由于其工作性质的特殊性,在使用时会产生很大的噪音和振动,这些因素会导致机器关键零部件产生疲劳损伤,影响整个机器的结构特性和工作稳定性,间接影响着日常的作业环境和工作效率,严重的振动甚至能对机器自身造成不可修复的破坏,进而影响使用寿命。振动是影响仪器设备正常工作的关键因素,强烈的振动会对破碎机的转速校准精度造成显著影响。因此,为降低颚式破碎机的振动频率,通过对颚式破碎机进行系统建模,并采用C++编程辅助计算,分析了机械系统的振动来源,应用机械系统动力学相关知识,对系统惯性力进行分析,并对破碎机结构进行优化：通过改变破碎机飞轮的偏心配重以及配重角度,使得偏心轴、飞轮和大带轮的质心满足颚式破碎机运动构件的质心运动方程。实验表明,该方法能够将系统的惯性力降低到优化前的三分之二。     

颗粒粉碎过程及设备(一)

正粉碎是颗粒物料生产的基本操作之一,其目的在于提升不同物料的均匀混合度,便于原料颗粒内的成分进行分离,提高物料的流动性,实现物料的流态化操作,提高物料干、溶解等工艺性能。颚式破碎机1.颚式破碎机的构造(1)简摆颚式破碎机图1所示为1200mm×1500mm简摆颚式破碎机。机架1的上部装有两对互相平行的轴承,     

颗粒粉碎过程及设备(一)

<正>粉碎是颗粒物料生产的基本操作之一,其目的在于提升不同物料的均匀混合度,便于原料颗粒内的成分进行分离,提高物料的流动性,实现物料的流态化操作,提高物料干燥、溶解等工艺性能。颚式破碎机工作原理及类型颚式破碎机是无机非金属材料工业中广泛应用的粗、中碎机械。根据其动颚的运动特征,颚式破碎机可分为简单摆动型、复杂摆动型和综合摆动型三种形式,如图1所示。     

双腔颚式破碎机动态破碎力分析

为提高双腔颚式破碎机破碎力计算的准确性,使用速度瞬心法,分析双腔颚式破碎机偏心轴旋转360°动颚的运动规律及破碎腔的变化规律,提出有效破碎腔折算系数,并对破碎力的变化规律进行分析.结果表明,破碎力随有效破碎腔的变化呈周期性变化,修正了最大破碎力计算公式,得出双腔颚式破碎机在偏心轴转至（水平向右逆时针转起）170°时左腔破碎力达到最大值,转至350°时右腔破碎力达到最大值.对完善双腔颚式破碎机的基础理论有重要意义.     

简述五种破碎设备的发展历程及研究状况

破碎机是冶金、矿山、化工、电力、陶瓷、水泥、建筑和筑路等工业部门广泛应用的重要设备。本文以颚式破碎机、圆锥式破碎机、辊式破碎机、锤式破碎机、反击式破碎机五种常用破碎设备为例,重点介绍其发展历程及研究现状。     

冲击式粘土破碎机和湿粘土质原料破碎烘干机

冲击式粘土破碎机和湿粘土质原料破碎烘干机汪一佛（中国建筑材料科学研究院，北京１０００２４）１湿粘土破碎机的工作原理和技术性能１．１工作原理破碎机是由带三个活动辊和板锤转子体等部件组成的破碎系统。它主要借助高速旋转转子体上的板锤，冲击湿土块进行破碎，被...     

A Study of Premature Failure of Crusher Jaws

In this article, we report the outcome of an investigation made to uncover the premature fracture of crusher jaws produced in a local foundry. A crusher jaw that had failed while in service was studied through metallographic techniques to determine the cause of the failure. Our investigation revealed that the reason for the fracture was the presence of large carbides at the grain boundaries and in the grain matrix. This led to the formation of microcracks that propagated along the grain boundaries under in-service working forces. It is also believed that the precipitation of carbides at the grain boundaries may have occurred because of improper heat treatment, but not because of a deficiency in composition.     

Ein Zerkleinerungskennwert für Betone

Based on quasi-brittle fracture models, a brittleness parameter is derived which characterises the resistance of concrete materials against mechanical fragmentation. Fragmentation tests in a laboratory jaw crusher are performed to verify this parameter. The brittleness parameter includes compressive strength and maximum aggregate size which can both be evaluated easily in practice. Resistance against mechanical fragmentation decreases if values for the brittleness parameter increase.     

井下移动式破碎机垂直方向随机振动响应的研究简

 为了研究井下移动式破碎机在破碎头受随机载荷作用下垂直方向的振动特性、探究其工作可靠性低的原因,通过假设与简化,根据多体动力学理论,建立了其动力学模型和垂直方向的运动方程,运用虚拟激励法推导了破碎机垂直向振动响应的数学模型．以国产某型井下移动式破碎机为研究对象,分析确定了破碎头冲击岩石时的随机载荷,运用MATLAB语言程序,得到该破碎机在高位时受随机载荷作用下破碎头、支臂与机身在垂直方向的随机振动响应．结果表明：在载荷峰值为375 kN、均值为186 kN、频率为10 Hz的随机激励作用下,该机各部振幅峰值与均值分别为：破碎头：0.0125 m,0.007 25 m;支臂：0.010 m,0.006 57 m;机身：0.006 1 m,0.003 62 m,可见各部振动比较剧烈．破碎头振动和波动最大,支臂次之,机身最小,与实际情况相符．当各部件振幅达最大时,破碎头、支臂与机身的低频与固有频率接近,容易发生共振,这是导致机器振动剧烈,引起零部件、元器件失效,使用寿命下降的主要原因．所得结论为改进移动式破碎机设计、采取合理的减振措施、延长破碎机使用寿命提供参考．     

低碳中合金钢破碎机锤头的研制

研究了一种新型的破碎机锤头,对其采用合金化处理并经过热处理,实验表明:该低碳中合金耐磨钢的硬度大于51HRC,冲击韧性大于141J/cm2。经热处理后的显微组织为回火马氏体+残余奥氏体+弥散的碳化物,比高锰钢破碎机锤头性能有很大提升。     

On the separation and recycling behaviour of textile reinforced concrete: an experimental study

This paper presents the results of recent experiments on the recyclability of the textile components in textile reinforced concrete (TRC). TRC as a multi-component system often contains organic ingredients such as carbon fibres and polymer impregnations. Consequently, the recycling of TRC is not trivial and has not yet been sufficiently clarified until now. In this study, an impregnated, bi-axially reinforced, and warp-knitted textiles made of carbon fibres was used in combination with a fine grained concrete. Flexural tests on TRC specimens containing recycled epoxy-impregnated carbon reinforcement were performed, whereby the recycling was simulated by a pre-treatment of the carbon fibre material in a jaw crusher. The results showed a pronounced decrease in flexural strength compared to untreated carbon reinforcement. Moreover, three different crushing methods were investigated with respect to their influence on the recovery of styrene-butadiene-rubber impregnated carbon textiles. Besides jaw crushing and impact milling, crushing with a hammer mill showed the best degree of purity but also caused the highest mechanical damage to the textile. The impact of material, structure of the composite and crushing methods on the separation behaviour could be deduced from the experiments.     

Modeling of the compression of coated papers in a soft rolling nip

An analytical model is developed for the compression of coated substrates in a soft rolling nip formed between a hard roll and a soft covered roll. The coating layer, substrate, and soft cover are modeled as a stack of three layers that are compressed jointly while passing through the nip. Material models have been adopted separately for each of the three layers and were combined together according to the thickness of individual layers. In this study, the substrate is considered to be a viscoelastic–plastic material and is represented by a modified solid element while the coating layer is assumed to be elastic and the soft cover material is approximated by a standard Maxwell model. A strain function is derived for the compression of substrate in the nip that appears to be a parabolic function of time. Substrate compression in the nip and its subsequent relaxation are calculated by solving a set of differential equations that describe the coating, substrate, and soft cover deformations. This model is used to study the soft-nip calendering of coated papers. Examples of numerical modeling that demonstrate the paper deformation and stress profiles in the nip are presented. In addition, the effects of paper and cover properties as well as calendering parameters on the dynamics of paper compression are discussed. Finally, a comparison of the modeling results is made with the experimental data.     

低合金马氏体耐磨钢的工况适应性

破碎、粉磨作业设备中,内衬板的选用往往不被重视,一些耐磨性好的材料,因不能适应工况条件而降低了使用寿命。通过调整马氏体钢的成分,经热处理后,进行工况条件的耐磨适应性试验,使马氏体钢的成分和组织在特定工况条件下的耐磨性最优化,可以提高内衬板的使用寿命,降低成本,提高生产效益。     

Numerical Design of Synchronous Generators

High power density applications require special treatment in design optimization. Among the critical questions is how the working torque angle will change through an optimization analysis. We present a new method for computing and using the synchronous reactance that accounts for the torque angle in the midst of complex parameter changes. The challenge is to tally this effect along with the load power factor into a variable metric optimization. Our new technique both computes this reactance under heavy saturation and integrates it into the machine design. The technique also covers appropriate stator current excitation densities in transient and steady-state excitation.