Research on swinging unit multi-point die with discrete elastic cushion in flexible stretch forming process

2016 ◽  
Vol 91 (1-4) ◽  
pp. 237-245 ◽  
Author(s):  
Jian Xing ◽  
Yan-yan Cheng ◽  
Ming-zhe Li
Keyword(s):  
Stretch Forming ◽  
Forming Process ◽  
Elastic Cushion

Numerical Analysis for the Multi-Point Stretch Forming Process of Aircraft Skin Panel

2011 ◽  
Vol 109 ◽  
pp. 504-508 ◽  
Author(s):  
Yu Shan Deng ◽  
Yuan Yao ◽  
Shao Hui Wang
Keyword(s):  
Numerical Analysis ◽  
Numerical Simulations ◽  
Equivalent Strain ◽  
Stretch Forming ◽  
Forming Process ◽  
Outer Skin ◽  
Free Length ◽  
Aircraft Skin ◽  
A New Technique ◽  
Elastic Cushion

Multi-point stretch forming (MPSF) is a new technique to form aircraft outer skin panel. Since multi-point die is composed by the discrete punches, the result of the MPSF aircraft outer skin panel need to study in depth. The thickness of elastic cushion and free length are two important factors to affect the accuracy, and they must be chosen reasonably. A series of numerical simulations on typical MPSF processes were carried out to an aircraft outer skin panel part. The results show that the thicker the elastic cushion is, the more valid the dimple will be suppressed .The longer free length is, the smaller the equivalent strain and thinning and more uniform the distribution of thickness will be. When the free length is shorter, the degree of effect is relatively obvious on the equivalent strain and thinning and the distribution of thickness; when the free length is longer than a certain value, the degree of effect is small.

Numerical Analysis of the Multi-Point Stretch Forming Process of Aircraft Outer Skin Part

2010 ◽  
Vol 154-155 ◽  
pp. 1068-1072
Author(s):  
Shao Hui Wang ◽  
Zhong Yi Cai ◽  
Ming Zhe Li ◽  
Ying Wu Lan
Keyword(s):  
Numerical Simulation ◽  
Numerical Analysis ◽  
Flexible Manufacturing ◽  
Stretch Forming ◽  
Forming Process ◽  
Outer Skin ◽  
Free Length ◽  
Simulation Results ◽  
The Cost ◽  
Elastic Cushion

As a flexible manufacturing technique, Multi-point stretch forming (MPSF) is a suitable method for forming aircraft outer skin part. The traditional solid stretching die is replaced by the discrete multi-point die (MPSD), and the sheet metal is stretch-formed over the MPSD generated by serial adjusting mode or parallel adjusting mode. The MPSF can be used to form the parts of different shape and reduce the cost and leading time of stretching die fabrication for aircraft outer skin part. A series of numerical simulations on typical MPSF processes of aircraft outer skin part were carried out. The thickness of elastic cushion and free length are important factors to influence on the stretch forming results of stretch-formed parts. The numerical simulation results show that the thicker the elastic cushion is, the more valid the dimple will be suppressed .The longer the free length is, the easier the wrinkle will be brought.

A New Stretch-Forming Process Based on Loading at Discrete Points and its Numerical Investigation

2013 ◽  
Vol 423-426 ◽  
pp. 737-740
Author(s):  
Zhong Yi Cai ◽  
Mi Wang ◽  
Chao Jie Che
Keyword(s):  
Sheet Metal ◽  
Three Dimensional ◽  
Discrete Point ◽  
Stretch Forming ◽  
Sheet Metal Part ◽  
Metal Part ◽  
Forming Process ◽  
Loading Trajectory ◽  
New Process ◽  
Forming Defects

A new stretch-forming process based on discretely loading for three-dimensional sheet metal part is proposed and numerically investigated. The gripping jaw in traditional stretch-forming process is replaced by the discrete array of loading units, and the stretching load is applied at discrete points on the two ends of sheet metal. By controlling the loading trajectory at the each discrete point, an optimal stretch-forming process can be realized. The numerical results on the new stretch-forming process of a saddle-shaped sheet metal part show that the distribution of the deformation on the formed surface of new process is more uniform than that of traditional stretch-forming, and the forming defects can be avoided and better forming quality will be obtained.

Flexible Stretch Forming Technology for Sheet Metal Based on Discrete-Gripper and Multi-Point Die

2014 ◽  
Vol 556-562 ◽  
pp. 460-463 ◽  
Author(s):  
Xue Chen ◽  
Ming Zhe Li ◽  
Wen Hua Liu ◽  
Zhi Qiang Hou
Keyword(s):  
Sheet Metal ◽  
Experimental Results ◽  
Shape Error ◽  
Stretch Forming ◽  
Forming Process ◽  
Structural Composition ◽  
Forming Technology ◽  
Working Principle ◽  
Material Utilization

To solve the problem of low material utilization in traditional stretch forming process, a flexible stretch forming method was proposed, which can be realized by interaction of the multi-point stretch forming die with discrete-gripper stretch forming machine. The principle and characteristics of sheet metal flexible stretch forming technology was introduced, structural composition and working principle of the multi-point stretch forming die and discrete-gripper stretch forming machine were expounded, and the technology experiments was carried out with a self-designed flexible stretch forming technology equipment for sheet metal. The experimental results indicate that structure of multi-point stretch forming die and discrete-gripper stretch forming machine are reasonable, and flexible stretch forming technology can be realized by above-mentioned die and machine, stretch forming parts has a good quality and its shape error can satisfy requirements of production.

Principle and Simulation Study on Multi Point-Single Point Incremental Combined Forming for Sheet Metal

2009 ◽  
Vol 626-627 ◽  
pp. 273-278 ◽  
Author(s):  
X.J. Li ◽  
Ming Zhe Li ◽  
C.G. Liu ◽  
Zhong Yr Cai
Keyword(s):  
Sheet Metal ◽  
Single Point ◽  
Experimental Result ◽  
Work Piece ◽  
The Novel ◽  
Forming Process ◽  
Explicit Finite Element ◽  
Forming Defect ◽  
Forming Technology ◽  
Elastic Cushion

Based on Multi-Point (MP) forming technology and Single-Point Incremental (SPI) forming technology, MP-SPI combined forming method for sheet metal is proposed, the principle and two different forming techniques are illustrated firstly. Then the paper is focused on numerical analysis for the novel forming technique with explicit Finite Element (FE) algorithm. During simulation of spherical work-piece, dimpling occurs as a main forming defect in MP-SPI combined forming process. Simulation results show that the dimpling defect can be suppressed effectively by using elastic cushion. An appropriate thickness of elastic cushion is necessary to prevent dimpling. And also the deformation of the work-piece is sensitive to the shape of elastic cushion. The combined forming test shows that the numerical simulation result is closed to the experimental result.

Influence of Element Number on Shape Accuracy in Multi-Point Stretch Forming of Air Craft

2011 ◽  
Vol 130-134 ◽  
pp. 2240-2244
Author(s):  
Jing Ling Wang ◽  
Zhong Yr Cai ◽  
Mine Zhe Li ◽  
Hui Yang
Keyword(s):  
Flexible Manufacturing ◽  
Three Dimensional ◽  
Great Influence ◽  
Stretch Forming ◽  
Forming Process ◽  
Shape Accuracy ◽  
Part Quality ◽  
Die Surface ◽  
Dimensional Shape ◽  
Element Number

Multi-point stretch forming is a flexible manufacturing technique for three-dimensional shape forming of craft skin. Its die surface is constructed by many pairs of matrices of elements whose height is controlled by computer. It uses the curved surface of elements instead of the die surface. The element numberis an important parameter because it has great influence on the part quality. This paper simulates the forming process of paraboloid part and saddle-shaped part with different number of elements and studies the influence of element number on the shape accuracy of the part .That will provides guidance for the application of multi-point stretch forming.

Study on Forming Process of Stretch Forming Lattice Structure

2021 ◽  
Author(s):  
Wang Cheng ◽  
Li Jianhua ◽  
Lu Chenghui
Keyword(s):  
Lattice Structure ◽  
Stretch Forming ◽  
Forming Process
Sign in / Sign up

Export Citation Format

Share Document