LD-M_1磨削液简介

LD-M_1磨削液是为解决人造金刚石压机顶锤、压缸等YG-8硬质合金的磨削加工而研制的。是一种不含矿物油，动、植物油，不含亚硝酸钠等有毒物质的非离子型的新型化学合成磨削液。     

弧三角孔型整体磨削的误差计算

分析了Ｙ型轧机弧三角孔型整体磨削误差计算原理，明确了整体磨削误差计算的思路，指出了整体磨削误差计算的方法和步骤。     

Y型轧机弧三角孔形整体磨削的误差计算

分析了Y型轧机弧三角孔形整体磨削误差计算原理 ,明确了整体磨削误差计算的思路 ,指出了整体磨削误差计算的方法和步骤。     

平面磨削的磨削力数学模型研究

为了获得磨削淬硬的切向磨削力进而确定磨削温度场的热源强度,通过对单个磨粒切削状态分析简化,在因次解析法的基础上建立平面磨削力的数学模型,利用试验验证了其有效性,进一步分析了磨削用量对磨削力的影响规律。研究结果表明:切向磨削力和法向磨削力误差均6.81%,验证了所建平面磨削力数学模型的有效性。     

如何防止渗碳淬火齿轮磨削裂纹的产生

通过对 2 0CrMnTi热处理过程中的组织变化 ,表层应力的消除方法、机加工过程中的磨削参数选择、砂轮的选择、磨削液的选择等分析 ,提出了防止磨削裂纹产生的措施     

如何防止渗碳淬火齿轮磨削裂纹的产生

针对20CrMnTi渗碳淬火齿轮在磨齿过程中容易产生磨削裂纹而报废的现象,通过对其热处理过程中的组织变化,表层应力的消除方法,机加工过程中的磨削参数选择、砂轮的选择、磨削液的选择等进行分析,提出了防止磨削裂纹产生的措施。     

磨具磨削时被加工表面微观形貌的研究

用近似旋转椭圆体单一磨削微粒切削被加工表面的模拟方法,展示微观切削过程中,被磨削表面的参数变化规律,确定磨削加工过程中磨具材料单位体积中磨削微粒数量Z、磨削微粒前面切削刃面积、切屑厚度的计算方法;提出切削中材料分离过程和变形过程所在变形区厚度的定义。     

砂带磨削接触有限元分析

针对砂带磨削中接触状况,研究磨削轮与工件的接触应力关系,利用有限元方法,使用MSC.MARC软件对某型号磨削轮进行应力分析,得出接触应力影响因素的影响程度,指导磨削轮设计和恒压强磨削控制。     

大理石磨削条件对磨具磨削性能的影响

本文研究了定压端面磨削大理石时,磨削加工条件对磨削生产率和加工表面质量的影响;分析了磨具磨损特征;提出了合理选择加工条件的原则。实验结果与理论分析相一致,可供生产厂家参考。     

岩石平面磨削信号的EAR模型与Lyapunov指数

根据实验检测的切削信号，分别建立了不同磨削条件下的颤振位移和磨削力的ＥＡＲ模型，同时依据已建立的ＥＡＲ模型，通过Ｌｙａｐｕｎｏｖ指数的分析计算，探讨混沌可能出现的切削条件，进而判断磨削系统是否发生混沌现象     

掘进工作面射流通风流场研究

掘进工作面压入式通风实际上是有限空间的受限贴附射流通风． 根据流体力学和射流理论, 分析了掘进通风射流产生过程及掘进工作面压入式通风风流结构． 风流从圆形风筒射入掘进工作面形成射流区和回流区． 给出了回流区平均速度、最大回流速度及射流作用距离的计算模型, 为掘进工作面合理有效通风提供了新的理论依据．     

立磨腔内气相流场数值模拟与分析

利用计算流体力学软件对立磨腔内气相流场的分布特性进行数值模拟分析,摸清腔内流场的分布规律,并对腔内局部结构进行优化设计。模拟结果表明:立磨腔内的流场主要由周向涡流和纵向涡流耦合而成,并在风环、灰斗和旋转磨辊的影响下变得十分复杂;在选粉区域呈现出沿顺时针旋转的强制涡流,且在部分导风叶片间产生局部二次涡流,认为导风叶片的安装角度应随位置的不同而有所改变。就风环结构中的导风锥对立磨腔内流场的影响做了深入研究,为立磨的结构优化设计和进一步研究提供了方法和依据。     

基于CFD超细磨用搅拌装置关键参数影响研究

在分析超细磨技术要求的前提下,通过分析盘式、螺旋式、叶轮式、棒式四种常用搅拌装置型式,确定了盘式是较为适合的超细磨用搅拌装置。利用计算机仿真流体力学建立了仿真分析模型,进行仿真分析。通过仿真得到了搅拌装置的流场分布状态和输入功率变化情况,重点分析了转速、搅拌元件直径、间距、面积比与流场、功率间的影响关系及变化范围。通过仿真明确了搅拌转速的范围为300~800r/min,搅拌元件直径的范围在150~170mm,搅拌元件间距的范围为30mm左右,空隙面积比的范围为0.15~0.35。各参数的确定为实验和工业中超细磨技术和设备的研发奠定了基础。     

煤超微粉碎双圆盘气流粉碎机的分级系统设计

用于煤的超微粉碎的气流粉碎机能最小限度地减小杂质混入,能够较好地保持超微煤粉颗粒的粒形,具有纯度高、设备简单、可靠性高等优点。设计了一种双圆盘气流粉碎机用于煤的超微粉碎,其分级系统采用压缩气体作介质。进入分级机内的气固两相流沿内壁旋转,并由外向内运动,产生离心力场和向心力场,同时在高速旋转分级转子的作用下,使得气流产生的离心力场和向心力场迅速增加,这样进入分级机内的煤粉颗粒受到离心力和向心力的平衡作用而分级,分级后粒径为3～100μm。     

立式辊磨机内部空气流场特性的仿真研究

首先介绍了立式辊磨机的结构和工作原理,然后在此基础上利用计算流体动力学仿真软件对立式辊磨机内部的空气流场分布特性进行了数值仿真研究。数值仿真结果表明,在立式辊磨机内部存在一个巨大的漩涡,该漩涡的存在不仅严重浪费了系统的能量,而且还改变了磨盘上物料层的稳定性,加剧了整个系统的运行不稳定性。初步揭示了立式辊磨机内部的空气流场分布特性,并为系统的结构优化提供了一定的依据。     

机械动能磨制备硬质高岭土微粉的工艺参数研究

为了避免高岭土在传统的湿法和普通机械磨超细粉碎过程中引入大量其他杂质,从而造成高岭土纯度降低,研究采用绵阳流能粉体设备有限公司的LNI-330A型机械动能磨对高岭土进行超细粉碎。在分级机转速为1 087 r/min,粉碎主机转速为120 m/s,系统风量为5 400 m³/h,二次风量为465 m³/h,主气流流量为3 523 m³/h情况下,最大产量为397 kg/h,激光粒度分析和扫描电镜分析表明,高岭土微粉的d₅₀<4 μm,呈现结构有序和形貌定型化的特征。     

Investigating flow conditions in dynamic air classification

Operating conditions during the air classification process, of critical importance for many grinding operations, were tested in laboratory scale. For efficient and satisfactory operation, the most important parameters, such as air flow rate, concentration of material in the air, rotor speed, wear rate, classification capacity and efficiency, require optimization. This paper indicates the influence of operating parameters on the classification process and provides optimization examples carried out by practical testing. On-line particle size and concentration measurement from Malvern Insitec was used to investigate the flow conditions during testing. Direct on-line measurement was possible inside the classifier circuit, thanks to the “multi-scattering” algorithm system, designed for the on-line measurement of highly concentrated particles in flows ranging from static to supersonic.     

DEM simulation of the flow of grinding media in IsaMill

IsaMill is a high speed stirred mill for high efficiency grinding of mineral ores and concentrates. A numerical model based on the discrete element method (DEM) was developed to study flow of grinding media in IsaMill. The DEM model was first verified by comparing the simulated results of the flow patter, mixing pattern and power draw from those measured from a 1:1 scale lab mill. Then the flow properties were analysed in terms of flow pattern, flow velocity, force field and power draw. The effects of parameters relating to particle material (i.e., sliding friction coefficient and damping coefficient) and operational conditions (i.e., rotation speed and solid loading) were investigated. While the damping coefficient showed a negligible effect for the range considered, other three parameters had strong effects on the flow properties. Increasing the sliding friction caused the flow velocity and compressive force to have minimum values due to the competitive mechanisms for energy transfer and dissipation, but increased the power draw. The increase in the rotation speed and solid loading also increased the flow velocity, compressive force and power draw of mill. The particle scale information obtained would be useful to understand the fundamentals governing the flow of grinding media in IsaMill.     

Slurry flow in a tower mill

Tower mills are a commonly used device for fine grinding in the mineral processing industry and can be used for dry or wet-grinding applications. In wet grinding, the nature of the slurry flow plays an important role in transporting feed rock and ground fines inside the mill and also assists discharge from the mill. Operating conditions and impeller design can affect the slurry distribution within the mill with some regions of the charge potentially being drier and others saturated. To help understand the slurry distribution and transport we use a two stage modelling process. The Discrete Element Method (DEM) is used to characterise the motion and distribution of the grinding media in the tower mill. The averaged voidage distribution and steady velocity field from the DEM model is then used to define a dynamic porous media in the fluid model. The Smoothed Particle Hydrodynamics (SPH) method is used for modelling the fluid flow because of the free surface and the moving impeller. The one way coupled DEM/SPH model is then used to assess how the fluid distribution and flow pattern of the slurry in a tower mill are to variations in the slurry viscosity.     

Computational prediction of performance for a full scale Isamill: Part 2 – Wet models of charge and slurry transport

The Isamill is a horizontal stirred media mill used for fine and ultrafine grinding of slurry transported rock particles. The charge motion is analysed using two different approaches, (1) a fluid only model, and (2) a 1-way coupled DEM + SPH model. The flow pattern when the classifier is closed is regular with a pair of oppositely oriented vortices between each pair of grinding discs. A strong radial outflow from the middle of the classifier is generated by the high centrifugal force which creates a pair of toroidal vortices at the discharge end of the mill. The classifier, when open, acts as a pump drawing slurry axially along the mill. It enters the classifier through the holes in its end plate and is then forced radially outward by rotational acceleration of the classifier cage. The enhanced outflow significantly strengthens the large toroidal vortices on the outside of the classifier. This produces a strong retrograde annular flow along the mill shell that penetrates a significant distance back into the grinding chamber. The effect of the classifier is significant and strongly influences the flow over much of the mill and controls slurry (feed and product) transport and discharge. The predictions of the different models are qualitatively similar but with important differences including the fluid only model predicting higher flow speeds because it cannot capture the strong slip between the media and the grinding discs. The strength of the axial transport is strongly dependent on the slurry viscosity. A critical viscosity can be identified above which there is insufficient axial transport to enable mill operation.