Application of IDA Method for Hull Plate Forming by Multi-Point Press Forming

J. Ocean Eng. Technol. 2008;22(6):75-82.

Yoon Jong-Sung,Lee Jang-Hyun,Ryu Cheol-Ho,Hwang Se-Yun,Lee Hwang-Beom

Graduate School Inha University,Department of Naval Architecture and Ocean Engineering Inha University,Graduate School Inha University,Graduate School Inha University,Graduate School Inha University

다점 프레스를 이용한 곡면 성형의 가공 정보 산출을 위한 IDA방법

윤종성,이장현,유철호,황세윤,이황범

인하대학교 대학원 선박공학과,인하대학교 기계공학부 선박해양공학,인하대학교 대학원 선박공학과,인하대학교 대학원 선박공학과,인하대학교 대학원 선박공학과

Keywords: Spring-back, FEA Finite element analysts, IDA(Iterative displacement adjustment), Multi-point press forming

핵심용어: 스프링 백, 유한요소해석, 순환적 변환 조정, 다점 프레스

Abstract

Flame bending has been extensively used in the shipbuilding industry for hull plate forming In flame bending it is difficult to obtain the desired shape because the residual deformation dependson the complex temperature distribution and the thermal plastic strain. Mechanical bending such as reconfigurable press forming multi-point press forming or die-less forming has been found to improve the automation of hull plateforming because it can more accurately control the desired shape than line heating. Multi-point forming is a process in which external forces are used to form metal work-pieces. Therefore it can be a flexible and efficient forming technique. This paper presents an optimal approach to determining the press-stroke for multi-point press forming of curved shapes. An integrated configuration of Finite element analysis (FEA) and spring-back compensation algorithm is developed to calculate the strokes of the multi-point press. Not only spring-back is modeled by elastic plastic shell elements but also an iterative algorithm to compensate the spring-back is applied to adjust the amount of pressing stroke. An iterative displacement adjustment (IDA) method is applied by integration of the FEA procedure and the spring-back compensation work. Shape deviation between the desired surface and deform