金属板料的成形及冲裁-------外文翻译冲压模具设计成型方面.doc

毕 业 设 计（论 文） 英 文 翻 译 课题名称 基于UG的高顶盖后板修边模参数化设计 系 部 材 料 工 程 系 专 业 材料成型及控制工程 班 级 KT633-01 学 号 2006K330130 姓 名 何杏4 Sheet metal forming and blanking 4.1 Principles of die manufacture 4.1.1 Classification of dies In metalforming,the geometry of the workpiece is established entirely or partially by the geometry of the die.In contrast to machining processes,ignificantly greater forces are necessary in forming.Due to the complexity of the parts,forming is often not carried out in a single operation.Depending on the geometry of the part,production is carried out in several operational steps via one or several production processes such as forming or blanking.One operation can also include several processes simultaneously(cf.Sect.2.1.4). During the design phase,the necessary manufacturing methods as well as the sequence and number of production steps are established in a processing plan(Fig.4.1.1).In this plan,the availability of machines,the planned production volumes of the part and other boundary conditions are taken into account. The aim is to minimize the number of dies to be used while keeping up a high level of operational reliability.The parts are greatly simplified right from their design stage by close collaboration between the Part Design and Production Departments in order to enable several forming and related blanking processes to be carried out in one forming station. Obviously,the more operations which are integrated into a single die,the more complex the structure of the die becomes.The consequences are higher costs,a decrease in output and a lower reliability. Fig.4.1.1 Production steps for the manufacture of an oil sump Types of dies The type of die and the closely related transportation of the part between dies is determined in accordance with the forming procedure,the size of the part in question and the production volume of parts to be produced. The production of large sheet metal parts is carried out almost exclusively u