scholarly journals PREDICTION AND ENHANCEMENT OF THICKNESS REDUCTION IN MULTI-POINT FORMING PROCESS USING ANOVA ALGORITHM

2019 ◽  
Vol 19 (1) ◽  
pp. 92-104
Author(s):  
Tahseen F Abaas ◽  
Karem M Younis ◽  
Khalida K Mansor
Keyword(s):  
Analysis Of Variance ◽  
Thickness Reduction ◽  
Model Parameters ◽  
Forming Process ◽  
Minimum Thickness ◽  
Blank Holder ◽  
Response Parameter ◽  
Multipoint Forming ◽  
Thickness Deviation ◽  
Reconfigurable Die

Multipoint forming is an engineering concept which means that the working surface of the dieand/or punch is made up of hemispherical ends of individual active elements (called pins), whereeach pin can be independently, vertically displaced using a geometrically reconfigurable die,precious production time is saved because several different products can be made withoutchanging tools. The aim of this work is to present the effect of many parameters (blank Holdertypes, rubber thickness and forming speed) on the reduction of thickness for brass with 0.71 mmthickness. This research is concentrate on the development of predictive models to estimate theminimum deviation in thickness using analysis of variance (ANOVA), minimum thicknessdeviation has been modeled. In the development of this predictive model, blank holder, rubberthickness and forming speed have been considered as model parameters. Arithmetic theminimum thickness deviation used as response parameter to assess the thickness reduction ofMultipoint forming parts. The data required has been generated, compared and evaluated to theproposed models that obtained from experiments. Taguchi algorithm is used to predict theeffect of forming parameters on thickness reduction in forming process of Brass (65-35) basedon orthogonal array of L9. The analysis of variance was used to find the best factors that effecton the thickness deviation, The result of this research is the contribution of blank holder types,rubber thickness and forming speed with respect to minimum thickness deviation is (69.195,18.1 and 12.733) % respectively.

scholarly journals Prediction of Process Parameters That Affecting on Surface Roughness in Multi-Point Forming Process Using ANOVA Algorithm

2019 ◽  
Vol 15 (2) ◽  
pp. 70-79
Author(s):  
Tahseen Fadhil Abbas ◽  
Karem Mohsen Younis ◽  
Khalida Kadhim Mansor
Keyword(s):  
Surface Roughness ◽  
Product Quality ◽  
Prediction Models ◽  
Model Parameters ◽  
Forming Process ◽  
Blank Holder ◽  
Response Parameter ◽  
Optimum Parameters ◽  
Multipoint Forming ◽  
Reconfigurable Die

  Multipoint forming process is an engineering concept which means that the working surface of the punch and die is produced as hemispherical ends of individual active elements (called pins), where each pin can be independently, vertically displaced using a geometrically reconfigurable die. Several different products can be made without changing tools saved precious production time. Also, the manufacturing of very expensive rigid dies is reduced, and a lot of expenses are saved. But the most important aspects of using such types of equipment are the flexibility of the tooling. This paper presents an experimental investigation of the effect of three main parameters which are blank holder, rubber thickness and forming speed that affect the surface integrity for brass (Cu Zn 65-35) with 0.71 mm thickness. This paper focuses on the development of prediction models for estimation of the product quality. Using Analysis of Variance (ANOVA), surface roughness has been modeled. In the development of this predictive model, blank holder, rubber thickness and forming speed have been considered as model parameters. The mean surface roughness (Ra) is used as response parameter to predict the surface roughness of multipoint forming parts. The data required has been generated, compared and evaluated to the proposed models obtained from experiments. Taguchi algorithm was used to predict the forming parameters (blank holder, rubber thickness and forming speed) on product roughness in forming process of Brass (Cu Zn 65-35) based on orthogonal array of L9 and finally ANOVA was used to find the optimum parameters that have effect on the product quality.

Optimization of Deep Drawing Processes Using Statistical Design of Experiments

1996 ◽  
Author(s):  
Dietrich Bauer ◽  
Regine Krebs
Keyword(s):  
Mathematical Model ◽  
Analysis Of Variance ◽  
Orthogonal Array ◽  
Deep Drawing ◽  
Metal Forming ◽  
Drawing Process ◽  
Drawing Force ◽  
Forming Process ◽  
Deep Drawing Process ◽  
Metal Forming Process

Abstract For a deep drawing process some important controllable variables (factors) upon the maximum drawing force are analyzed to find a setting adjustment for these process factors that provides a very low force for the metal forming process. For this investigation an orthogonal array L18 with three-fold replication is used. To find the optimum of the process, the experimental results are analyzed in accordance with the robust-design-method according to Taguchi (Liesegang et. al., 1990). For this purpose, so-called Signal-to-Noise-ratios are calculated. The analysis of variance for this S/N-ratios leads to a mathematical model for the deep drawing process. This model allows to find the pressumed optimal settings of the investigated factors. In the following, a confirmation experiment is carried out by using these optimal settings. The maximum drawing force of the confirmation experiment does not correspond with the confidence interval, which was calculated by analysis of variance techniques. So the predicted optimum of the process does not lead to a metal forming process with very low deep drawing force. The comparison with a full factorial plan shows that there are interactions between the investigated factors. These interactions could not be discovered by the used orthogonal array. Thus the established mathematical model does not describe the relation between the factors and deep drawing force in accordance with the practical deep drawing conditions.

Applying 2k Factorial Design to Study on Parameters Affecting Springback of Forming of Advanced High Strength Steel Sheets (AHSS)

2017 ◽  
Vol 872 ◽  
pp. 83-88
Author(s):  
Ramil Kesvarakul ◽  
Chamaporn Chianrabutra ◽  
Watcharapong Sirigool
Keyword(s):  
Elastic Recovery ◽  
Weight Ratio ◽  
High Strength ◽  
Die Design ◽  
Statistical Experimental Design ◽  
Blank Holder Force ◽  
Forming Process ◽  
Blank Holder ◽  
Punch Radius ◽  
Springback Angle

Advanced high strength steels (AHSS) are widely used in the automotive industry due to their appropriate strength to weight ratio. This alloy has unique hardening behavior and variable unloading elastic modulus; however, the unavoidable obstacle of AHSS sheet metal forming is springback. The springback is a result of elastic recovery and residual stress. The aim of this study is to determine the proper process parameters enabling the reduction of the springback defects in AHSS forming process. This work was divided into two parts, regarding to the effects of numerical parameters and process parameter on forming AHSS. In this paper, a U-shape forming was used to examine the springback behaviors, such as springback angle, sidewall curl, and thickness, through an experiment. To achieve this purpose, 2k factorial statistical experimental design has been employed to investigate the parameters affecting the springback of forming in AHSS to find out the main effect in the springback reduction focusing on using as a guideline for die design. It showed that the blank holder force is the most influential parameter. The second is the punch radius. However, the blank holder force and punch radius is not simple to adjust in die design, the die radius becomes the important parameter to be used to reduce the springback angle.

scholarly journals Investigation of Slip Occurrence in the Ring Rolling Process

2019 ◽  
Vol 291 ◽  
pp. 02006
Author(s):  
Andrzej Gontarz ◽  
Piotr Surdacki
Keyword(s):  
Wall Thickness ◽  
Failure Modes ◽  
Rolling Process ◽  
Ring Rolling ◽  
Thickness Reduction ◽  
Main Stage ◽  
Forming Process ◽  
Limit Values ◽  
Ring Shape ◽  
Ring Rolling Process

Ring rolling is a hot forming process for producing rings that have large diameters when compared to their cross sections. This process is very dynamic and involves considerable variations in ring shape and size. One of the failure modes in ring rolling processes is slip that occurs when a thickness reduction, exceeds the limit value. The thickness reduction depends on the tool speed and dimensions as well as ring size, and varies over time. This paper reports results of a study investigating the thickness reduction with respect to slip occurrence. In terms of wall thickness reduction, the process can be divided into three distinct stages (excluding the sizing stage): (i) initial stage corresponding to the first revolution of the roll, (ii) main stage, when the proper ring rolling takes place, (iii) final stage, when the main roll does not move in an axial direction but the ring is being formed during one revolution of the tool. It has been found that the most slip-prone moment is the end of the second and the beginning of the third stage of the ring rolling process, when the wall thickness reduction is the highest. Based on a comparison of the calculated thickness reduction and its limit values, it could be predicted whether slip would occur, and if so – in what stage of the rolling process. Numerical results and experimental findings are in good agreement.

scholarly journals Reconfigurable Multipoint Forming Using Waffle-Type Elastic Cushion and Variable Loading Profile

Materials ◽  
2020 ◽  
Vol 13 (20) ◽  
pp. 4506
Author(s):  
Mohammed Moheen ◽  
Adel Abdel-Wahab ◽  
Hany Hassanin ◽  
Khamis Essa
Keyword(s):  
Process Parameters ◽  
Fem Analysis ◽  
Thickness Variation ◽  
Variable Loading ◽  
Shape Deviation ◽  
Multipoint Forming ◽  
Base Radius ◽  
Manufacturing Techniques ◽  
Elastic Cushion ◽  
Reconfigurable Die

There is an increasing demand for flexible, relatively inexpensive manufacturing techniques that can accommodate frequent changes to part design and production technologies, especially when limited batch sizes are required. Reconfigurable multi-point forming (MPF) is an advanced manufacturing technique which uses a reconfigurable die consisting of a set of moveable pins to shape sheet metal parts easily. This study investigates the use of a novel variable thickness waffle-type elastic cushion and a variable punch-loading profile to either eliminate or minimise defects associated with MPF, namely wrinkling, thickness variation, shape deviation, and dimpling. Finite element modelling (FEM), analysis of variance (ANOVA), and the response surface methodology (RSM) were used to investigate the effect of process parameters pertaining to the cushion dimensions and type of loading profile on the aforementioned defects. The results of this study indicate that the most significant process parameters were maximum cushion thickness, cushion cut-out base radius, and cushion cut-out profile radius. The type of loading profile was found to be insignificant in all responses, but further investigation is required as the rate, and the thermal effects were not considered in the material modelling. Optimal process parameters were found to be a maximum cushion thickness of 3.01 mm, cushion cut-out base radius of 2.37 mm, cushion cut-out profile radius of 10 mm, and a “linear” loading profile. This yielded 0.50 mm, 0.00515 mm, 0.425 mm for peak shape deviation, thickness variation, and wrinkling, respectively.

The Impact Analysis of Stamping Process Factors Based on Dynaform

2013 ◽  
Vol 712-715 ◽  
pp. 642-646
Author(s):  
Zhen Gang He ◽  
Yan Ping Zheng ◽  
Gai Yan
Keyword(s):  
Quality Evaluation ◽  
Impact Analysis ◽  
Simulation Analysis ◽  
Blank Holder Force ◽  
Forming Process ◽  
Blank Holder ◽  
Stamping Process ◽  
The Coefficient Of Friction ◽  
Process Factors ◽  
The Impact

Combining with practical needs in production, it carried out the numerical simulation analysis of automobile beam stamping forming process based on Dynaform in this paper. According to quality evaluation index of forming parts, it analyzed the effect of variation of blank holder force, the stamping speed, the coefficient of friction and draw bead on stamping quality. It forecast the quality problems happened in forming process, which provides the theoretical basis for design of stamping process and mold.

scholarly journals Analysis of the multilayer woven fabric behaviour during the forming process: focus on the loss of cohesion within the woven fibre network

2019 ◽  
Vol 20 (4) ◽  
pp. 407
Author(s):  
Ahmad Rashed Labanieh ◽  
Christian Garnier ◽  
Pierre Ouagne ◽  
Olivier Dalverny ◽  
Damien Soulat
Keyword(s):  
Woven Fabric ◽  
Carbon Fabric ◽  
Mechanism Of Formation ◽  
Forming Force ◽  
Forming Process ◽  
Plane Shear ◽  
Blank Holder ◽  
Fibre Network ◽  
Process Loss

The first step in the composite manufacturing process consists of forming a flat textile reinforcing structure into a 3D shape. The quality of the final composite part is affected by the presence of defects induced during the forming process. Loss of cohesion in the woven fibre network (intra-ply yarn sliding) is a frequent defect in the forming process. It is expected when the cohesion between the yarns is weak or when the blank holder pressure is high. However, the mechanism of formation of this defect is not fully understood. In the present study, forming experiments with friction-based holder have been conducted for a monolayer twill woven carbon fabric in two orientations and for two plies of this fabric with different relative orientations. The occurrence of the intra-ply yarns sliding has been observed as a function of the blank holder pressure. A correlation between the occurrence of this defect and the fabric orientation has been noticed. Furthermore, the effect of the fabric orientation, number of plies, relative plies orientation and blank holder pressure on the recorded forming force and on the fabric in-plane shear is also reported and analysed.

Research Progress and Application of Multi-Point Forming

2011 ◽  
Vol 221 ◽  
pp. 679-683
Author(s):  
Hui Min Li ◽  
Wei Gang Guo
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Automotive Industry ◽  
Research Progress ◽  
Aviation Industry ◽  
Body Frame ◽  
Forming Process ◽  
Reconfigurable Die ◽  
Element Method

The research progress was introduced about multi-point forming press. It include forming process, reconfigurable die and finite element method. The forming method provided the techonology for development of the aviation industry and automotive industry. The application prospect and techonology dominance were instructed by illuminating body frame of coach.

Effect of Blank Holder Force with Low Frequency Vibration Technique in Circular-Cup Deep-Drawing Using AZ31 Magnesium Alloy Sheet

2011 ◽  
Vol 383-390 ◽  
pp. 2785-2789
Author(s):  
Naoki Horiike ◽  
Shoichiro Yoshihara ◽  
Yoshitaka Tsuji ◽  
Yusuke Okude
Keyword(s):  
Deep Drawing ◽  
Low Frequency ◽  
Lubricating Oil ◽  
Drawing Process ◽  
Blank Holder Force ◽  
Forming Process ◽  
Blank Holder ◽  
Deep Drawing Process ◽  
Low Frequency Vibration ◽  
Friction Performance

In the deep-drawing process, the application of low-frequency vibration to the blank material has recently been focused on with the aim of improving the friction performance between the die and the blank material. A servo-controlled press machine is suitable for applying low-frequency vibration to the blank during the deep-drawing process, because the punch speed and blank holder force (BHF) are easily controlled as process parameters by using the servo motors. In this study, a BHF with low-frequency vibration was proposed as a technique for improving deep-drawability, which is mainly affected by the friction performance and the lubricant condition. We found that the friction performance between the blank surface and the blank holder was decreased in the case of a BHF with low-frequency vibration since the lubricating oil rapidly flowed into the clearance during the forming process. Furthermore, for a BHF with low-frequency vibration, the punch force and the deformation resistance were lower than those in a deep-drawing test without low-frequency vibration.

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