Spring-back analysis in the cold-forming process of ship hull plates

2018 ◽  
Vol 96 (5-8) ◽  
pp. 2341-2354 ◽  
Author(s):  
Wei Shen ◽  
Renjun Yan ◽  
Shuangyin Li ◽  
Lin Xu
Keyword(s):  
Back Analysis ◽  
Ship Hull ◽  
Spring Back ◽  
Forming Process ◽  
Cold Forming

Numerical and experimental analysis on cold-forming and spring-back of hull plate

2018 ◽  
Vol 233 (3) ◽  
pp. 561-569 ◽  
Author(s):  
Wei Shen ◽  
Renjun Yan ◽  
Shuangying Li
Keyword(s):  
Three Dimensional ◽  
Dimensional Accuracy ◽  
Ship Hull ◽  
Laser Forming ◽  
Successive Approximation Method ◽  
Spring Back ◽  
Forming Process ◽  
Cold Forming ◽  
Thick Plates ◽  
Forming Mechanism

Ship hull structures are fabricated by curved thick plates before they are welded together. There are traditional methods such as, line heating and laser-forming methods for plate bending. However, it is recognized that the hot-forming technology causes a series of troubles on doubly or multiple curved plates. Multi-point forming mechanism with square press heads is a new forming process for three-dimensional ship hull plate. Cold-forming has a high dimensional accuracy but results in spring-back. The spring-back process of curved thick plates in the finite element method is analyzed and the predicted results are compared with the test results in the present paper. To ensure the forming precision, the successive approximation method is also developed and verified to control the spring-back.

Nonlinear Finite Element Analysis of Spring-Back Characteristics in the Cold-Forming Process of Three-Dimensionally Curved Thick Metal Plates

2013 ◽  
Vol 135 (3) ◽  
Author(s):  
Jeom Kee Paik ◽  
Jeong Hwan Kim ◽  
Bong Ju Kim ◽  
Chang Hyo Tak
Keyword(s):  
Finite Element ◽  
Three Dimensional ◽  
Steel Plates ◽  
Research Centre ◽  
Spring Back ◽  
Forming Process ◽  
Element Analysis ◽  
Cold Forming ◽  
Metal Plates ◽  
National University

The present paper is part of the study to develop the advanced computer aided manufacture (CAM) system called the changeable die system (CDS) that applies the cold-forming technique to produce curved thick metal plates with complex, three-dimensional geometry [Paik et al., 2009, “Development of the Changeable Die System for the Cold-Forming of Three-Dimensionally Curved Metal Plates,” The Lloyd's Register Educational Trust Research Centre of Excellence, Pusan National University, Korea]. This paper focuses on the procedure of predicting the spring-back characteristics using elastic-plastic large deflection finite element method, which is a key technical element within the framework of the CDS process. The validity of the procedure is confirmed by comparison with experimental results obtained by the CDS machine in the cold-forming process of curved steel plates.

Comparison of Material Behavior and Economic Effects of Cold and High Temperature Forming Technologies Applied to High-Strength Steels

2005 ◽  
Vol 6-8 ◽  
pp. 101-108 ◽  
Author(s):  
Reimund Neugebauer ◽  
Angela Göschel ◽  
Andreas Sterzing ◽  
Petr Kurka ◽  
Michael Seifert
Keyword(s):  
Elevated Temperatures ◽  
High Strength Steels ◽  
Dimensional Accuracy ◽  
High Strength ◽  
Economic Effects ◽  
Material Behavior ◽  
Spring Back ◽  
Forming Process ◽  
Cold Forming ◽  
Forming Tools

The focus of forming high-strength steel at elevated temperature is to improve its forming properties like elongation and to reduce the power requirements during the forming process in opposite to cold forming. Because of the undefined and large spring-back effects parts made by cold forming are not able to achieve the demanded dimensional accuracy, which is necessary for laser welding operations in car body assembly. The reduction of the spring-back behavior is another advantage of the temperature controlled forming technology. On the other side the forming at elevated temperatures requires increased costs for forming tools and tempering equipment. For a fundamental evaluation of this technology, expenditures for the complete process chain have to be considered.

Analysis of Spring-Back Behavior in the Cold-Forming Process of Three-Dimensionally Curved Metal Plates

2010 ◽  
Author(s):  
Jeom Kee Paik ◽  
Jeong Hwan Kim ◽  
Bong Ju Kim ◽  
Chang Hyo Tak
Keyword(s):  
Three Dimensional ◽  
Nonlinear Finite Element ◽  
Steel Plates ◽  
Nonlinear Finite Element Method ◽  
Spring Back ◽  
Forming Process ◽  
Cold Forming ◽  
Metal Plates ◽  
Computer Aided ◽  
Advanced Computer

The present paper is part of the study to develop the advanced computer aided manufacture (CAM) system called the changeable die system (CDS) that applies the cold-forming technique to produce curved metal plates with complex, three-dimensional geometry. This paper focuses on the algorithm of predicting the spring-back behavior using nonlinear finite element method, which is a key element within the framework of the CDS process. The validity of the algorithm is confirmed by comparison with experimental results obtained by the CDS machine in the cold-forming process of curved steel plates.

Grain Size Modification by Micro Rotary Swaging

2015 ◽  
Vol 651-653 ◽  
pp. 627-632 ◽  
Author(s):  
Svetlana Ishkina ◽  
Bernd Kuhfuss ◽  
Christian Schenck
Keyword(s):  
Grain Size ◽  
Longitudinal Section ◽  
Forming Process ◽  
Boundary Area ◽  
Cold Forming ◽  
Flat Surfaces ◽  
Rotary Swaging ◽  
2D Simulation ◽  
Physical Tests ◽  
Formed Part

Rotary swaging is a well established cold forming process e.g. in the automotive industry. In order to modify the material properties by swaging systematically, a new process of swaging with asymmetrical strokes of the forming dies is investigated. The newly developed tools feature flat surfaces and do not represent the geometry of the formed part as in conventional swaging. Numerical simulation and physical tests are carried out with special regard to the resulting geometry, mechanical properties and the microstructure. During these tests copper wires with diameter d0=1 mm are formed. Regarding the microstructure in the longitudinal section of formed specimens, elongation of grains in the central part and grain size reduction in the boundary area are observed. Furthermore, this approach opens up new possibilities to configure the geometry of wires. 2D-simulation is applied and discussed in the paper to investigate change of the processed geometry (cross-section) and shear strain distribution during the rotary swaging process.

Numerical Study of the Flow Forming Process of AISI 630 Stainless Steel

2011 ◽  
Vol 264-265 ◽  
pp. 24-29 ◽  
Author(s):  
Seyed Mohammad Ebrahimi ◽  
Seyed Ali Asghar Akbari Mousavi ◽  
Mostafa Soltan Bayazidi ◽  
Mohammad Mastoori
Keyword(s):  
Feeding Rate ◽  
Surface Defects ◽  
Numerical Study ◽  
Internal Diameter ◽  
The Finite Element Method ◽  
Forming Process ◽  
Flow Forming ◽  
Cold Forming ◽  
External Variables ◽  
Experimental Process

Flow forming is one of the cold forming process which is used for hollow symmetrical shapes. In this paper, the forward flow forming process is simulated using the finite element method and its results are compared with the experimental process. The variation of thickness of the sample is examined by the ultrasonic tests for the five locations of the tubes. To simulate the process, the ABAQUS explicit is used. The effects of flow forming variables such as the angle of rollers and rate of feeding of rollers, on the external variables such as internal diameter, thickness of tube and roller forces are considered. The study showed that the roller force and surface defects were reduced with low feeding rate and low rollers attack angles. Moreover, the sample internal diameter increased at low feeding rate and low rollers attack angles. The optimum variables for flow forming process were also obtained.

Machine Learning Acoustic Emission Based Monitoring of Cold Forging for Smart Manufacturing: A Review

2021 ◽  
Vol 2 (3) ◽  
Keyword(s):  
Machine Learning ◽  
Acoustic Emission ◽  
Product Quality ◽  
High Speed ◽  
High Rate ◽  
Cold Forging ◽  
Smart Manufacturing ◽  
Forming Process ◽  
Cold Forming ◽  
Effective Manner

Cold forging is a high-speed forming technique used to shape metals at near room temperature. and it allows high-rate production of high strength metal-based products in a consistent and cost-effective manner. However, cold forming processes are characterized by complex material deformation dynamics which makes product quality control difficult to achieve. There is no well defined mathematical model that governs the interactions between a cold forming process, material properties, and final product quality. The goal of this work is to provide a review for the state of research in the field of using acoustic emission (AE) technology in monitoring cold forging process. The integration of AE with machine learning (ML) algorithms to monitor the quality is also reviewed and discussed. It is realized that this promising technology didn’t receive the deserving attention for its implementation in cold forging and that more work is needed.

Research of Characteristic of Wrinkling in Cold Forming Process for Ship Frame Part Based on Numerical Simulation

2015 ◽  
Author(s):  
Pei-Yong Li ◽  
◽  
Jun-jie Song ◽  
Cheng-fang Wang ◽  
Yun-sheng Mao ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Forming Process ◽  
Cold Forming

Study on the Formability of the Seam Welded Tube for Manufacturing the Drive Shaft

2013 ◽  
Vol 631-632 ◽  
pp. 708-712
Author(s):  
Bong Joon Kim ◽  
Eun Soo Park ◽  
Won Yong Byeon ◽  
Dal Joon Cha ◽  
Yong Nam Kwon
Keyword(s):  
Weld Line ◽  
Reduction Process ◽  
Rear Wheel ◽  
Drive Shaft ◽  
Cold Reduction ◽  
Roll Forming ◽  
Forming Process ◽  
Cold Forming ◽  
Geometrical Defects ◽  
The Impact

In this study, cold reduction process of the tubular metal is applied to manufacture the drive shaft for the rear wheel drive system. With this method during forming process, chip forming such as hobbing and broaching method is not involved. The manufacturing process is as follows; the tube which the sheet is formed and welded to by roll forming machine, is mounted on a suitable mandrel. This mandrel has an external toothing which corresponds to internal toothing of the final product. During axial moving and rotating of the workpiece, forming operation is carried out in lengthwise direction of the toothing. This forming rolls is positioned on the roll head and have a rolling axis vertical with the one of a mandrel. The total forming load needed in the cold reduction process is separated into numerous forming steps along the entire cylindrical length of the zone to be formed. In the process of cold forming on the profiled mandrel during the impact forming operation, material is pushed into depression of toothing of a mandrel mainly in a radial direction. Finally splines can be generated on the surface of components and overall elongated. If the process parameter such as the length of forming per 1rotation of 1roll is not optimized, the impact force from the rolls of the forming process causes geometrical defects. So the optimal parameters such as feeding and rotating speed of workpiece and the forming length should be properly determined. And the effects of the weld line positioning on the formability of the forming process is analyzed to minimize the generation of the defects such as crack on the surface of splined zone.

Sign in / Sign up

Export Citation Format

Share Document