Production of Thin Outer Skin Car Body Panels by Using Novel Short Cycle Stretch-Forming (SCS) Technology

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.

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Effects of process variation in short cycle stretch forming in beverage can production

10.1063/1.4963466 ◽

2016 ◽

Cited By ~ 1

Author(s):

Matthias Schneider ◽

Mathias Liewald

Keyword(s):

Process Variation ◽

Stretch Forming ◽

Short Cycle

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

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.154-155.1068 ◽

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.

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Batch Fluctuations in Short Cycle Stretch Forming of Tinplate can Bodies

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.794.105 ◽

2015 ◽

Vol 794 ◽

pp. 105-111 ◽

Cited By ~ 1

Author(s):

Matthias Schneider ◽

Mathias Liewald

Keyword(s):

Process Model ◽

Tensile Tests ◽

Stretch Forming ◽

Short Cycle ◽

Forming Technology ◽

Metal Thickness ◽

First Results ◽

In Series ◽

The University ◽

Main Effects

Short cycle stretch forming (SCS) is an innovative stretch forming technology, developed by the Institute for Metal Forming Technology (IFU) at the University of Stuttgart. The SCS technology combines plane pre-stretching and deep drawing operations within the same stroke of the press ram. The sheet metal thickness is reduced, and the denting resistance as well as the yield stress are increased due to hardening effects.In this study, the SCS technology is applied to rotational-symmetric bodies. A process simulation of an SCS cupping process was carried out for producing tinplate cans. Based on these results, a tool was produced. First results showed that the metal thickness of cups for two-piece drawn and ironed (D&I) steel can bottoms can be reduced. With this technological goal, it is possible to save the material cost in series production.This paper analyses how batch fluctuations affect the thinning of cup bottoms in SCS cupping. Therefore, preliminary experiments have been conducted, using their results to improve the previously used FE process model. With the aid of this model, an FEA-based parametric study on the variation of material properties is conducted. To examine batch fluctuations, tensile tests have been taken into account, and initial material parameters for simulation, such as friction coefficient, initial blank thickness, Lankford parameter and hardening behaviour, have been varied.The results of this paper show that SCS cupping offers a promising potential for material savings and demonstrate the main effects of batch fluctuations.

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Approach for Implementation of Short Cycle Stretch Forming (SCS) to Cupping Processes

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.611-612.1096 ◽

2014 ◽

Vol 611-612 ◽

pp. 1096-1101 ◽

Cited By ~ 5

Author(s):

Matthias Schneider ◽

Mathias Liewald

Keyword(s):

Metal Forming ◽

Stretch Forming ◽

Short Cycle ◽

The University ◽

Stretching Process

Short Cycle Stretch Forming (SCS) is a new stretching process patented by the Institute for Metal Forming (IFU) of the University of Stuttgart in 2006 [. It was mainly developed for outer car panels like doors [ and roofs [ with the aim of:

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Process Effects in Short Cycle Stretch Forming of Tinplate Can Bodies

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.716.494 ◽

2016 ◽

Vol 716 ◽

pp. 494-501

Author(s):

Matthias Schneider ◽

Mathias Liewald

Keyword(s):

Research Work ◽

Tool Geometry ◽

Stretch Forming ◽

Serial Production ◽

Short Cycle ◽

Forming Technology ◽

Metal Thickness ◽

Process Effects ◽

The University ◽

Main Effects

Short Cycle Stretch Forming (SCS) is an innovative stretch forming technology developed at the Institute for Metal Forming Technology (IFU) at the University of Stuttgart. The SCS technology combines plane pre-stretching of blank and subsequent deep drawing operations within the same stroke of press ram. The sheet metal thickness is reduced while denting resistance and yield stress increases due to hardening effects.Current research work focuses on applying SCS-technology to rotational-symmetrical bodies. A process simulation for SCS-Cupping process was performed for food cans. Based on these results a tool was manufactured and commissioned. The results showed that the thickness of cup bottoms of two-piece drawn and ironed (D&I) steel cans can be reduced. Therefore, it is possible to save material costs in serial production based on a reduced blank diameter.In this paper the different effects leading to the thinning of steel can bottom and failure types, such as, wrinkling and cracking are observed in a number of experimental series. Based on these results, the tool geometry was optimized and an advanced tool was manufactured. The results of this paper show that SCS-Cupping offers promising potential to save material, as well as outlining the main effects for this technology.

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