某结合齿热锻模具开裂数值模拟分析及改进

针对某结合齿热锻过程中模具发生开裂失效的问题,通过有限元模拟软件对锻造过程进行了模拟分析,得出模具发生开裂的主要原因为危险处拉应力超过模具材料的抗拉强度。针对模具开裂失效原因,提出两种解决模具开裂失效的方法,一是优化预锻坯形状,二是优化模具结构,即采用分体式模具结构代替整体式模具结构。优化后的模拟结果表明,采用分体式模具结构大大减小了危险处拉应力值,从而避免了模具的早期失效。实际生产结果也表明,采用分体式模具结构大大提高了模具寿命。     

优化模具结构提高模具寿命QM50QT-H后转向灯壳注射模的改进

本文提出了注塑模具在生产中的变形问题,选用低合金工具钢CrWMn经热处理代替45调质钢,改善了模具局部强度及硬度,同时将模具型芯由整体结构改为镶拼式结构,彻底解决了模具的变形问题,优化了模具结构设计,提高了模具寿命。     

基于变密度法的级进模模具结构拓扑优化设计

针对多工位级进模模具,提出了一种基于变密度法的级进模模具结构拓扑优化方法。先通过板材冲压成形有限元数值模拟得到变形板料对模具的作用力,利用自主开发的载荷映射工具构建级进模模具结构分析的力边界条件;再通过模具结构分析,明确模具结构优化的空间;最后结合拓扑优化算法对模具结构进行了优化设计。以某汽车连接器件级进模模具为例对该方法加以验证,与按传统方法设计的模具相比,优化重构后的模具在重量保持不变的情况下最大变形量减小了36.5%。对优化重构后的级进模在冲压成形过程中的应变值进行了测量,应变实测值与结构分析结果比较吻合,表明文中所提出的级进模模具结构拓扑优化方法是切实可靠的。     

巨型工程车子午线轮胎活络模具结构设计

以40.00R57巨型工程车子午线轮胎活络模具为例,介绍了该活络模具的基本结构,并优化了模具结构,解决了模具的重量超重、容易变形等问题。模具结构合理,满足了生产和使用的要求。     

一种新的大方管铝型材挤压模结构

介绍了传统大方管铝型材挤压模过早失效的原因。详细分析了传统大方管挤压模的结构特点。提出了一种新的模具结构,阐述了这种模具结构的组成要素,说明了有关主要结构参数的选择,描述了这种新的结构的优点。通过对新旧模具结构的使用结果对比,表明了这种新的模具结构是有效的,是具有明显优势的,能大大提高模具的寿命,是一种值得推广的模具结构。目的在于向同行推广这一技术和这种新的模具结构,为广大设计者提供可靠、有效的参考。     

新型锥齿轮锻件切边模研制

锥齿轮锻件原切边模结构不尽合理,模块刃口加工方法落后,模具寿命低、切边质量差.提出新型切边模结构和刃口齿形设计计算公式,论述模具制造工艺、模块翻新和模具系列化方案.新型模具克服了原模具的缺点,显著提高了锻件切边质量和模具寿命,降低了模具成本.     

优化模具结构 提高模具寿命 QM50QT—H后转向灯壳注射模的改进

本文提出了注塑模具在生产中的变形问题，选用低合金工具钢CrWMn经热处理代替45调质钢，改善了模具局部强度及硬度，同时将模具型芯由整体结构改为镶拼式结构，彻底解决了模具的变形问题，优化了模具结构设计，提高了模具寿命。     

地垫注塑模具设计

从零件图的结构要素、注塑零件尺寸精度与形状位置精度等方面对地垫零件进行了注塑工艺性分析.对地垫塑料零件的注塑模具结构进行工艺性设计.本着在满足地垫注塑要求的情况下,模具结构尽量简单,以缩短模具制造周期,便于以后维修保养的原则,设计中将模具的基本结构确定为两板式单腔模具.并对地垫注塑模具的分型面、合模导向装置、主要工作零件结构、零件脱模推出装置、浇注系统进行了分项单元设计,并设计绘制了地垫注塑模具的总体结构图.     

多孔发射药挤压模具的结构参数优化

为了得到多孔发射药模具的合理结构参数,采用正交实验法设计模具结构参数组合。应用Workbench流固耦合模块模拟发射药药料在模腔内的挤压过程及针架的变形过程,得到模具最优结构参数组合,并通过挤压实验验证了所选模具结构参数的合理性。     

插座面板注射模设计

通过对插座面板的结构、尺寸和成型要求进行分析,确定了合理的模具结构.文中阐述了模具中的分型面、型腔与流道的布置、脱模机构与冷却机构、斜顶机构的结构设计,介绍了模具的工作过程.该模具采用一模四腔的结构.     

弹性阀座加工方法的改进

对弹性阀座的机械加工工艺和冲压加工工艺进行了对比,并分析了冲压加工所产生的误差,介绍了冲压加工的特点及级进模的结构。     

On thin rings and short tubes subjected to centrally opposed concentrated loads

The deformation behaviour of mild steel rings and short tubes of various diameters, thicknesses and lengths loaded centrally by opposed conically-headed cylindrical punches is examined. The test equipment and procedure are briefly described and typical histories of deformation, punch load—displacement diagrams and the increase in the horizontal ring or tube radius for increasing punch travel are presented. A comparison is made between the latter and those predicted by use of a simple expression based on the assumption of rigid-plastic material deformation. Good correlation is obtained with rings of different diameter to thickness ratio.     

通用可微调快换冲模设计

设计了一种可应用于组合冲模及柔性冲压系统的快换冲模机构。通过斜楔机构的设计，模具间隙可做微量调节，工作安全可靠。模具更换快捷、方便并带自锁功能。适合中小型冲压制品的多品种、中小批量生产及系列产品的开发。     

基于Mastercam的鼠标凹凸模具造型与加工

应用Masteream曲面造型方法完成鼠标凹模及凸模的造型,合理安排凹模及凸模的数控加工工艺,应用Mastercam强大的曲面加工方法进行鼠标凹模及凸模刀具参数设置粗、精加工切削参数设置及轨迹生成、模拟仿真并生成数控G代码,完成凹模及凸模的加工。     

冲裁模具间隙及凹模圆角对凸模应力应变影响的有限元分析

冲裁模具的间隙和凹模圆角,对凸模的应力、应变有重要的影响。运用有限元分析了冲裁模具在不同间隙与圆角下凸模的应力、应变特性。分析结果表明,应力、应变随着间隙和凹模圆角的增加而减小。模拟分析的结果为模具间隙和圆角半径的选择提供了依据。     

The effect of die/blank holder and punch radiuses on limit drawing ratio in angular deep-drawing dies

Deep-drawing is one of the most important methods used to form sheet metal. The radius of die/blank holder and punch is important for deep-drawing dies because of an effective way to promote deep drawability sheet metal. This paper presents an attempt to determine the effect of various radiuses of die and punch on the limit drawing ratio and was investigated using DIN EN 10130–91 sheet metal. The die/blank holder profile with angles of α?=?0°, α?=?2.5°, α?=?7.5°, α?=?12.5°, α?=?15° and die/punch profile with radiuses for R?=?10, R?=?8, R?=?6, R?=?4 and R?=?0 mm were analyzed to determine the influence of punch force on the limit drawing ratio. The aim of this study is to investigate the effect of radius and angle variables on drawability in the deep-drawing process and to obtain useful data from the industrial field. The experiments show that the limit drawing ratio increased with increasing radius of punch (R), die/blank holder angle (α).     

Effects of process variables on V-die bending process of steel sheet

This investigation aims to clarify the process conditions of the V-die bending operation of steel sheet. It provides a model which predicts the correct punch load for bending and the precise final shape of products after unloading, in relation to the tensile properties of the material and the geometry of tools. The process variables are punch radius (R_p), die radius (R_d), punch width (W_p), punch speed (V_p), friction coefficient (μ), strain hardening exponent (n) and normal anisotropy (R).This investigation is carried out by performing some experiments and by finite-element simulation. Experiments determine the punch for bending for various process variables, such as punch radius, punch speed and lubrication, were carried out. As a result it was found that punch load increases as punch radius and punch speed increase or lubrication decreases.An elasto-plastic incremental finite-element computer code based on an updated Lagrangian formulation was developed to simulate the V-die bending process of sheet metal under the plane-strain condition. Isotropic and normal anisotropic material behavior was considered including nonlinear work hardening. A modified Coulomb’s friction law was introduced to treat the alternation of sliding–sticking state of friction at the contact interface. Simulation results, such as the punch load of bending and the bend angle of the bent part after unloading, are compared with experimental data; satisfactory agreement was observed. The simulation clearly demonstrates that the code to simulate V-die bending process was efficient.Simulations were made to evaluate the effects of die radius, punch width, strain hardening exponent and normal anisotropy on punch load of bending. The punch load for bending is smaller for materials with a larger strain hardening exponent. The effect of punch width on punch load is limited. The punch load decreases in the early stage and increases in the final stage of the bending process as the die radius increases. The influences of all of the process variables on the final bend angle of the bent parts of sheet after unloading were also evaluated. The effects of process variables except die radius on the bend angle after unloading are also limited. The angle of spring-back is greater for tools with larger die radius.     

堆焊耐磨合金制造大型陶瓷模具模芯工艺

在４５钢上堆焊Ｄ３２Ｄ３２７合金制造大型模芯,实践证明,采用合理的堆焊工艺可在４５钢上获得较为满意的耐磨合金层,采用这一工艺,大型模芯的制造成本只是Ｃｒ１２ＭｏＶ钢制模芯的１／３￣１／４。     

汽车覆盖件模具凸型面拉延方法

针对汽车覆盖件这种具有复杂曲面特征的零件,在传统的全型面拉延成形方法基础上提出一种新的凸型面拉延成形方法。该方法根据拉延成形过程中凸、凹模工作型面上只有凸型面接触板料的特点,通过成形仿真获得全型面拉延的成形极限图(Forming limit diagram, FLD)和凸、凹模与板料的接触区域分布。然后将板料相对凸、凹模工作型面上的起皱区域及双面接触区域所对应的单元剔除,将单面接触区域中面积较小且形态狭长的单面接触区域合并转化为双面接触区域,同时将未转化的单面接触区域外周节点拟合成曲线后导入到CAD中对凸、凹模工作型面进行分割获得所需的凸型面。算例表明该方法在保证拉延成形质量的前提下可以有效地减小凸、凹模工作型面的面积,降低拉延模具的生产成本。     

滑块式弯曲模具设计与加工

通过对某音响底壳零件的结构及工艺分析,阐述了该零件的冲压工艺和模具设计、加工的要点,设计了滑块式弯曲模具的装配图及主要零部件图。实践表明:该零件的冲压工艺方案合理,模具结构型式新颖、加工工艺合理可靠。