基于专家系统的数控刀具选配系统的研究

在数控刀具选配实现过程中,采用专家系统的基本原理,使数控刀具选配更加方便与简洁。本文详细研究数控刀具事实库、规则库以及数控刀具选配系统推理机的设计方法,并建立了基于专家系统的数控刀具选配系统模型。最后提出数控刀具选配方案的评价方法。     

基于遗传算法的智能化刀具选配系统的开发

开发了智能化选刀系统的硬件;提出了基于遗传算法的智能化刀具选配方案,并介绍了将加工条件参数化为环境因素和将刀具信息参数化为基因的方法;构建了智能化选配系统的逻辑结构;通过模糊综合评判、概率统计等数学方法建立了刀具适用度函数的数学模型;以C++为平台编制了系统程序;并以实例对智能化选配系统进行了检测和评估。     

某航空发动机燃油喷嘴生产线智能刀具管理及选配系统研究

以国内某航空发动机生产公司对燃油喷嘴智能生产线刀具管理的需求现状为背景,针对其刀具准备计划和生产计划匹配效率低、刀具信息不畅通、现有刀具管理软件功能不全或冗杂、无法对刀具进行参数化的查询等问题,结合企业的个性化需求进行了系统功能需求分析,基于需求分析进行了系统功能模块的设计,并开发了一套相应的智能化刀具管理及选配系统.在系统实现中采用了B/S三层架构体系,使用了MVC设计模式,应用了面向对象的编程思想,使得各功能应用模块高度解耦.系统的实现与应用满足了该企业燃油喷嘴生产线刀具管理及选配的相关业务需求,实现了精细化、自动化、智能化管理.     

基于相似度的刀具选配方法研究

针对刀具选配过程中无法有效利用以往选配过程中积累的成功经验和数据的问题,提出了基于相似度的案例匹配方法,研究了加工案例中刀具选择的知识表示方法以及案例之间相似度的计算方法,用层次分析法建立刀具选配的权重决策模型,确定案例中各特征属性的权重,实现了基于历史案例的刀具的选配。     

面向企业信息化管理的刀具选配系统开发

通过对现代加工企业刀具使用流程的分析,以工件加工过程中刀具需求、刀具组配流程、工件与刀具材料匹配、刀具出入库管理、刀具采购、使用监控等实际使用环节为目标,开发了一套基于刀具使用全程的选配管理系统。系统的使用缩短了工装准备时间,提高了刀具的利用率,节省了加工时间,增强了企业的竞争力。     

基于规则挖掘的刀具智能选配技术研究

刀具的智能选配是CAPP系的过程,通过对影响因素的分析筛选,建立刀具选择评判因素集.采用数据挖掘的方法从已有的工艺经验中挖掘出刀具选配的潜在规则,建立刀具选配规则知识库,并以知识库为支撑,提出了一种刀具搜索优化算法,用于提高刀具选配的效率,为开发智能化SmartCAPP系统提供有力的支持.     

基于特征的刀具选配系统的研究与开发

通过分析工件的特征信息,利用规范化数据库技术进行了刀具选配系统的开发,使用该系统可在特征的基础上实现刀具类型、刀具组件信息和工件与刀具材料匹配等快速查询以及刀具的组配。     

基于特征的刀具“形-性-用”一体化设计方法

刀具作为机床的"牙齿",在金属切削中非常重要,目前专用化是刀具发展的一个主要趋势,挑战刀具设计的灵活性和准确性。为了实现这一目标,提出了刀具"形-性-用"一体化设计方法,它以加工需求为驱动,利用切削过程中涉及的理论(几何约束、切削力作用、切削层作用机理、刀具强度理论、高温材料学属性以及化学反应关系等),并通过刀具设计特征,将刀具的形状、性能和使用结合起来,进而实现针对加工需求的专用刀具设计,以及相应的加工条件和切削参数等的确定。然后建立了刀具"形-性-用"一体化设计方法系统框架,并开发了其软件平台。最后采用示例分析,展示本方法的刀具参数优化过程和刀具建模过程,进而证明本方法的可行性。刀具"形-性-用"一体化设计方法为刀具专用化发展提供一种新方法和新思路。     

基于生命库存理论的刀具管理系统研究与开发

针对现有刀具管理系统在库存管理方面研究不足的问题,本文基于生命库存理论研制了一种新型的刀具管理系统。系统的应用可以实现从刀具需求到报废的整个生命周期的信息实时有效的管理。研制的系统能够满足一般制造企业的需求,并从根本上提升刀具的管理品质。     

基于Web的数控车间刀具准时配送管理系统

为满足数字化生产线对先进配送与管理方法的迫切需求,提出了B／S模式的设计思想,采用J2EE架构开发了基于Web的数控车间刀具准时配送管理系统。分析了面向精益生产的数控车间刀具配送系统的功能需求,并运用UML语言对系统进行了建模。系统按功能可划分为基础数据管理、配送准备、配送执行、回收准备、回收执行五大模块。该系统能够有效缩短刀具配送时间,降低刀具的间接成本,提高实际生产效率。     

Automatic NC-Data generation method for 5-axis cutting of turbine-blades by finding safe heel-angles and adaptive path-intervals

In this paper, an efficient method tor generating 5-axis cutting data for a turbine blade is presented. The interference elimination of 5-axis cutting currently is very complicated, and it takes up a lot of time. The proposed method can generate an interference-free tool path, within an allowance range. Generating the cutting data just point to the cutting process and using it to obtain NC data by calculating the feed rate, allows us to maintain the proper feed rate of the 5-axis machine. This paper includes the algorithms for: (1) CL data generation by detecting an interference-free heel angle, (2) finding the optimal tool path interval considering the cusp-height, (3) finding the adaptive feed rate values for each cutter path, and (4) the inverse kinematics depending on the structure of the 5-axis machine, for generating the NC data.     

Selecting optimal tools for arbitrarily shaped pockets

As a result of slicing a 3D part into 2D pockets for generating tool paths, pockets are becoming more commonly used. When a pocket is machined, the question of which of the many feasible tools for cutting the pocket is best always arises. Will cutting be more efficient if multi-tools are used? Will the algorithm to choose the optimal tools be timesaving enough? This paper presents a method in which an upper bound O(N) is used to choose the optimal cutting tool combination, where N is the number of feasible tools available. The proposed method is quick and sufficient for computer-aided process planning (CAPP) and computer-aided manufacturing (CAM) environments.     

MACHINING PARAMETERS OPTIMIZATION FOR ALUMINA BASED CERAMIC CUTTING TOOLS USING GENETIC ALGORITHM

Alumina-based ceramic cutting tools can be operated at higher cutting speeds than carbide and cermet tools. This results in increased metal removal rates and productivity. While the initial cost of alumina based ceramic inserts is generally higher than carbide or cermet inserts, the cost per part machined is often lower. Production cost is the main concern of the industry and it has to be optimised to fully utilize the advantages of ceramic cutting tools. In this study, optimization of machining parameters on machining S.G. iron (ASTM A536 60-40-18) using alumina based ceramic cutting tools is presented. Before doing the optimization work, experimental machining study is carried out using Ti [C,N] mixed alumina ceramic cutting tool (CC 650) and Zirconia toughened alumina ceramic cutting tool (Widialox G) to get actual input values to the optimization problem, so that the optimized results will be realistic. The optimum machining parameters are found out using Genetic algorithm and it is found that Widialox G tool is able to machine at lower unit production cost than CC 650 tool. The various costs affecting the unit production cost are also discussed.     

MACHINING PARAMETERS OPTIMIZATION FOR ALUMINA BASED CERAMIC CUTTING TOOLS USING GENETIC ALGORITHM

Alumina-based ceramic cutting tools can be operated at higher cutting speeds than carbide and cermet tools. This results in increased metal removal rates and productivity. While the initial cost of alumina based ceramic inserts is generally higher than carbide or cermet inserts, the cost per part machined is often lower. Production cost is the main concern of the industry and it has to be optimised to fully utilize the advantages of ceramic cutting tools. In this study, optimization of machining parameters on machining S.G. iron (ASTM A536 60-40-18) using alumina based ceramic cutting tools is presented. Before doing the optimization work, experimental machining study is carried out using Ti [C,N] mixed alumina ceramic cutting tool (CC 650) and Zirconia toughened alumina ceramic cutting tool (Widialox G) to get actual input values to the optimization problem, so that the optimized results will be realistic. The optimum machining parameters are found out using Genetic algorithm and it is found that Widialox G tool is able to machine at lower unit production cost than CC 650 tool. The various costs affecting the unit production cost are also discussed.     

基于柔性制造系统的刀具编码应用研究

柔性制造系统主要适用于中小批量、多品种零件的加工,不同品种的零件需要配置不同类型的刀具,为了防止刀具在加工过程中的磨损、折断,还需配置一定数量的姊妹备刀。根据企业实际生产的现况看,相同种类的刀具数量可能至少需要3把,用于机床的切削加工;刀具磨损或折断时的备用;刀具库进行预调的准备。而整个生产制造过程需求的刀具数量将更多。对于柔性制造生产系统,每台加工中心可以配置的刀具至少在50把以上。按一条柔性制造系统生产线配备10台以上的CNC机床,则刀具的数量有可能达到500把以上。因此只有进行刀具编码才能管理这么多的刀具。     

高速加工原理及刀夹、刀具选用

高速切削加工能够大大提高切削速度 ,提高工件的加工质量和刀具的耐用度。在高速切削条件下 ,材料的切削机理将发生变化 ,切削过程将变得容易 ,切削热将降低。介绍了正在研究和应用的刀夹类型和刀具材料。     

金刚石刀具研磨质量的影响因素

金刚石刀具研磨非常困难,影响研磨质量的因素较多。     

钛合金BT20端铣试验研究

传统的钛合金加工工艺因其切削速度低、刀具耐用度低、机床功率不足的缺陷 ,导致了加工效率低。针对上述问题 ,对钛合金BT2 0进行了多次端铣试验 ,发现采用先进的刀具材料 ,优化刀具角度 ,使用大功率机床 ,在保证必要的刀具耐用度的前提下 ,完全可以提高切削速度 ,从而提高钛合金加工效率。     

虚拟轴机床刀具运动轨迹的直接控制

本文提出了虚拟轴机床刀具运动轨迹的直接控制方法,该方法可根据可信息和加工工艺信息,直接生成刀具希望轨迹和虚轴运动指令,并通过虚实变换对实轴的联动控制,从而有效保证刀具轨迹与希望轨迹一致,所得结果为开发新型虚拟轴机床控制系统奠定了基础。     

A manufacturing model of helical groove on rotary burr and a universal post processing method

A systematic machining theory and precision method to determine cutter location in a grinding system is presented for rotary burr. First, the helical cutting edge on various kinds of revolving surfaces is built. Then, based on the geometry model of the helical cutting edge, the smooth spiral rake surface with constant normal rake angle and flank surface can been formed during the one-pass grinding process by this method. No interference between the grinding wheel and workpiece happens by the wheel special rotation. The method has the characteristic of detaching the grinding wheel path solution from specified machining conditions. The grinding wheel path is suitable for different NC machine tools through post processing. Meanwhile, a mechanism kinematic model of the NC machine tool is built, and a generalized algorithm for post-processing of multi-axis NC machine tools is presented. This model is applied to arbitrary configuration of NC machine tool, and the motion value for each axis will be generated by the inputting structure and motion parameters of the machine tool. The model, together with the machining method mentioned in this paper, make the calculation and generation of the grinding wheel path simpler and universal. At last, the validity of the method given in the paper is identified by an example of grinding.