On the Study of Automatic Plate Bending

人们常说船舶工业的主要特点是船舶是由大尺寸的焊接结构组成的，而且船舶的结构，特别是在船头和船尾，是由自由曲面组成的。因此，板材弯曲是船舶生产中最重要的工艺之一，目前双曲率板材的弯曲多采用水火弯板工艺。而在造船自动化的过程中，板材弯曲是最复杂的一个过程，在造船工业中，开发自动化的板材弯曲设备一直是一个梦想。本文的主要工作如下：（1）研制了一台6 × 6活塞式自动卷板机样机（总载荷20吨）。(2)为了了解该设备的性能，对一百多块钢板进行了试验。(3)为了解设计端面形状与安装板形状之间的关系，开发了基于有限元法的计算程序NCBEND。利用NCBEND程序可以方便地计算板在弹塑性状态下的有限变形问题。(4)通过试验结果与计算结果的对比，初步建立了一种表面嵌入形状的估算方法。

It is often said that the main characteristics in shipbuilding industry are ship is composed of a large size of welded structures and also her structure, especially at fore and aft parts, is composed of free curved surfaces. Therefore plate bending is one of the most important techinique in ship production stage.Thus far line heating method is employed to bend a plate which has double curvatures. In order to make automated shipyard, however, plate bending process is the most complicated one.In shipbuilding industry, the development of automatic plagte bending facility has long been a dream. However, there were few study in the world In this paper, (1) A prototype of automatic plate bending facility is developed, in which 6x6 pistons are used (total load 20 ton). (2) In order to know the capability of the facility, more than a hundred of steel plates are tested. (3) To know the relation between design shape of face and set-in shape of plate, a calculation program called NCBEND based on finite element method is developed. By using the program NCBEND, a finite deformation problem of plate bending in the elastic-plastic stated can easily be calculated. (4) Comparing test results and calculated ones, a estimation method of set-in shape of surface is generally established.