等离子熔覆技术在导辊上的应用

为提高轧机导辊的耐磨和抗开裂性能,采用等离子熔覆技术,在45钢表面熔覆Al2O3掺杂Fe-Ni基高温耐磨合金涂层,利用扫描电子显微镜、X射线衍射仪研究熔覆层的组织结构,并在实验室研究基础上进行生产现场试验。结果表明:熔覆层组织细密均匀,其主要物相为γ-(Fe,Ni)、(Cr,Fe)7C3和少量FeAl、Fe0.23Ni0.77Al和Ni3Al金属间化合物;等离子合金导辊的使用寿命大大提高,综合性能评价值是普通高铬铸钢导辊的12倍。     

大规格圆棒用滚动导卫开度调节系统的改进

针对大规格圆棒生产用滚动导卫在轧制过程中导辊开度不能保持在设定值，影响产品质量及生产顺行的问题，通过对该类型导卫开度调节装置的工作原理及结构分析，明确了结构设计及选用材质与使用工况不匹配是问题产生的主要原因。为此，对调节装置进行了设计优化，改进后的导卫在线时间显著提高。     

大规格圆棒用滚动导卫开度调节系统的改进

针对大规格圆棒生产用滚动导卫在轧制过程中导辊开度不能保持在设定值,影响产品质量及生产顺行的问题,通过对该类型导卫开度调节装置的工作原理及结构分析,明确了结构设计及选用材质与使用工况不匹配是问题产生的主要原因。为此,对调节装置进行了设计优化,改进后的导卫在线时间显著提高。     

凸轮专用数控机床主轴的优化设计

本文以最小主轴重量及主轴前端挠度为优化目标，采用统一目标的线性组合法，引入加权因子，建立了一个统一的优化目标函数，对机床主轴进行了多目标优化设计，使优化结果更符合实际。     

New standardized procedure for the measurement of the static and dynamic properties of forming machines

The geometrical accuracy and the surface quality of sheet metal parts as well as the tool wear are influenced by process parameters and by static and dynamic interactions between the press and the tool. Therefore the qualitative characterization of the machine behavior is of high importance for both press manufacturers and press operators. Within research project (Behrens et al. in Entwicklung und Erweiterung standardisierter Messverfahren zur statischen und dynamischen Pressenvermessung. Final Report of the AiF Research Project 13742 N, 2005), a procedure for the measurement of the static machine behavior has been developed, which for the first time allows the standardized measurement of the ram deflection and the bolster plate deflection along with previously standardized characteristic values. The determination of the procedure as measurement directions and the automated evaluation of the measurements ensure not only reproducible results but also easy comparison of two machines. Additionally a new procedure for the measurement of the dynamic press behavior has been standardized which allows the comparison of the static and the dynamic characteristic values. The project [1] was funded under number AiF 13742 N by the Arbeitsgemeinschaft industrieller Forschungsvereinigungen “Otto von Guericke” e.V. with budget funds from the German Federal Ministry of Economics.     

Modeling and simulation of adaptronic drilling tool axes as the basis of control design

Drilling bars with great overhang are used for the purpose of deep drilling. Vibrations of the drilling bar and changing cutting forces based on form and position errors of a pilot hole are interrupting influences within the manufacturing process. Therefore the Fraunhofer IPT is developing an intelligent adaptronic drilling tool which enables the use of different redundant adaptronic systems each consisting of piezoactuators, solid-state joints and sensors in order to improve the accuracy of the drilling process. This paper presents the physical state-space model of the static und dynamic behaviour of one adaptronic system as the basis for further control synthesis and describes a useful tool for the multidiscipline design of the system. The starting model parameters are calculated by FEM-simulation and are fitted to measured data by an optimisation-algorithm based on Newton’s method. By describing the piezoelectric hysteresis the linear model of the mechatronic transfer behaviour is extended to a nonlinear model, which is the starting point for complex control designs for adaptronic machine tools.     

Influence of prestrain on the numerical simulation of the roller hemming process

This study focuses on the numerical simulation of roller hemming of an aluminium alloy sample with a curved geometry; this non-planar geometry is obtained by a prestrain procedure similar to deep drawing process. Material characterization was performed through tensile and simple shear tests at different orientations on the sheet plane. The influence of considering the Bauschinger effect, anisotropy, and the strain history on the final geometry was studied. A specific laboratory device for roller hemming was designed to forward an experimental database. The numerical simulation of the roller hemming of these samples is presented here, as well as the correlation between the calculations and the experimental tests, notably the roll-in value and the prediction of wrinkling.     

万能轧机导卫系统浅析

介绍了马鞍山钢铁股份有限公司H型钢厂万能轧机导卫系统的装配形式、设计原则和使用特点，同时介绍了当前H型钢轧制新工艺中所采用的万能轧机导卫系统。     

机床数控化改造中电磁兼容性问题探讨

普通机床的数控化升级改造，对于我国中小企业意义重大，数控设备的电磁兼容性问题是机床数控化改造的成败关键因素之一。本文重点讨论了数控机床的常见的电磁干扰源、干扰耦合途径以及抗电磁干扰的措施。     

基于有限元分析技术的VK50数控床身铣机床底座设计

介绍了基于有限元优化分析技术的VK50数控床身铣机床底座的开发设计过程,通过CAE技术对开发过程的支持,对机床底座结构进行了其动静态特性的计算机仿真及优化设计,实验表明改进后的机床底座具有良好的动静态特性,同时证明了CAE技术改造传统机床制造业的有效性及科学性.     

基于自激励的数控机床模态参数提取方法研究

提出了一种基于自激励的数控机床模态参数提取方法,利用该方法对XHK5140机床进行了实验模态分析,得到该机床的前4阶模态参数,并且将其和计算模态分析结果进行比较,验证了该方法的有效性。解决了传统模态实验设备难以激励大型数控机床的问题。     

棒材连轧机圆孔型入口滑动导板的新型式

通过改进棒材生产中圆孔型入口滑动导板的型式,成功地避免了生产中倒钢、卡钢等事故,提高了生产效率。     

Advanced experimental and numerical methods for the analysis of the dynamic forming press behavior

Numerical simulations are used to estimate the dynamic behavior of new concepts of forming presses as well as to improve the dynamic properties of existing machines. These simulations are to be parametrized with appropriate values in order to yield most accurate results. In many cases neither the way of building up the simulation model for the specific problem nor an appropriate method for gathering the needed date are given in advance. Regarding these facts this paper intends both to characterize the way of building up complex simulation models by using basic simulation modules and to describe methods for the identification of the needed parameters that work even under conditions that hitherto made parameter identifications impossible or at least very time-consuming. In this context recent developments in simulating press dynamics will also be characterized as new modal analysis methods that are not yet established in the field of forming technique. The research activities were financed by the European Research Association for Sheet Metal Working.     

同弧形导卫设计及应用

为解决小型车间导卫粘铁、耐磨性差的问题，采用了同弧形导卫设计方法，结果使导卫件的使用寿命提高3倍以上，导卫件的消耗及中间废品率降低3／4，轧机作业率提高2％。     

A Study on the Drive at Center of Gravity (DCG) Feed Principle and Its Application for Development of High Performance Machine Tool Systems

For high performance machining, it is essential to minimize the vibration of a machine tool, which is incurred due to the instantaneous acceleration/deceleration. To minimize this vibration, it is fundamentally ideal to apply the driving force at the most shock-insensitive position of the moving structure: the center of gravity. Aiming at developing unparalleled high-performance machine tool systems, the effectiveness of the Drive at the Center of Gravity (DCG) principle on vibration reduction has been studied thoroughly by analytical and experimental approaches. Based on the results obtained, a new design of the high-performance machine tools has been discussed with a special focus on the installation of DCG mechanism without sacrificing any advantages already obtained in the recent basic design rules. The paper also describes the comparative study between a machine tool based on the DCG principle and the one with a conventional driving configuration. The results obtained have shown a distinctive performance difference in machining stability.     

钢轨轧制过程典型导卫系统的有限元模拟

利用有限元模拟方法,对钢轨轧制生产过程中典型导卫系统进行模拟研究,借助大型有限元模拟软件MSC.Marc,分别讨论了入口导板和出口卫板对轧制过程以及轧件变形过程的影响。模拟结果表明,入口导板对轧件顺利咬入孔型以及轧件在该道次的变形过程产生显著影响,出口卫板对轧制过程的顺利进行产生显著影响。通过对模拟结果的分析认为,有限元模拟方法有助于实际生产过程中导卫系统的设计与优化;有限元模拟技术的应用,可提高导卫系统的可靠性,并对轧制过程提供有效而便捷的途径。     

Analytical modeling of spindle–tool dynamics on machine tools using Timoshenko beam model and receptance coupling for the prediction of tool point FRF

Regenerative chatter is a well-known machining problem that results in unstable cutting process, poor surface quality and reduced material removal rate. This undesired self-excited vibration problem is one of the main obstacles in utilizing the total capacity of a machine tool in production. In order to obtain a chatter-free process on a machining center, stability diagrams can be used. Numerically or analytically, constructing the stability lobe diagram for a certain spindle–holder–tool combination implies knowing the system dynamics at the tool tip; i.e., the point frequency response function (FRF) that relates the dynamic displacement and force at that point. This study presents an analytical method that uses Timoshenko beam theory for calculating the tool point FRF of a given combination by using the receptance coupling and structural modification methods. The objective of the study is two fold. Firstly, it is aimed to develop a reliable mathematical model to predict tool point FRF in a machining center so that chatter stability analysis can be done, and secondly to make use of this model in studying the effects of individual bearing and contact parameters on tool point FRF so that better approaches can be found in predicting contact parameters from experimental measurements. The model can also be used to study the effects of several spindle, holder and tool parameters on chatter stability. In this paper, the mathematical model, as well as the details of obtaining the system component (spindle, holder and tool) dynamics and coupling them to obtain the tool point FRF are given. The model suggested is verified by comparing the natural frequencies of an example spindle–holder–tool assembly obtained from the model with those obtained from a finite element software.     

活套装置中导辊与起套辊位置的探讨

探讨棒、线材轧机活套装置中导辊与起套辊的位置布置,并给出了其位置布置的设计计算方法。     

机床沿曲线高速进给加工的最大安全恒定进给速度的确定

分析了曲线、曲面轮廓数控加工中,刀具路径曲线的几何特性与机床运动学特性的关系,建立了机床沿曲线恒速进给的运动学方程;基于虚功原理推导出刀具路径几何特性、机床特性及电机特性等之间关系的动力学方程.并用解析法,计算了在各坐标轴加速度、伺服电机额定转矩及额定转速约束条件下,机床沿曲线进给时的最大安全恒定进给速度.在最大安全恒定进给速度范围内,选择合适的进给速度,既能使加工表面粗糙度均匀,保证加工表面质量,同时又能获得较高的高速加工效率.     

基于WEB的机床夹具异地设计研究

介绍了通过建立网站实现基于WEB的机床夹具产品异地设计的方法和意义以及用VRML语言建立夹具产品三维动画装配模型的方法。