Experimental research and numerical optimisation of multi-point sheet metal forming implementation using a solid elastic cushion system

Tolipov, Abror; Elghawail, Ali; Shushing, S.; Pham, Duc Truong; Essa, Khamis

doi:10.1088/1742-6596/896/1/012120

Cited by 5 publications

(4 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This assumed that parameters with p -values of less than 0.05 were deemed to be statistically significant. The smaller the p-value below this threshold, the more significant the process parameter [ 38 , 44 ]. The null hypothesis specified that none of the investigated parameters was significant.…”

Section: Resultsmentioning

confidence: 99%

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

et al. 2020

View full text Add to dashboard Cite

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.

show abstract

Section: Resultsmentioning

confidence: 99%

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

et al. 2020

View full text Add to dashboard Cite

show abstract

“…Kareem and Imad [3] studied the influence of localised deformation on the quality of the deformed sheet and the importance of using the elastic cushion in reducing the formation of dimples, but they also found that using a very thick elastic cushion degrades the accuracy of the fabricated part. On the other hand, Essa et al [2,8,20] studied the effect of elastic material, friction coefficient and thickness on the surface quality. They were able to optimise the elastic material type and thickness for better product quality parts.…”

Section: Introductionmentioning

confidence: 99%

Multipoint forming using mesh-type elastic cushion: modelling and experimentation

Tolipov

Elghawail

Abosaf

et al. 2019

Int J Adv Manuf Technol

View full text Add to dashboard Cite

There is a growing demand for flexible manufacturing techniques that meet the rapid changes in production technology, processes and innovations. Multipoint forming (MPF) is a flexible sheet metal forming technique where a reconfigurable die can be readily changed to produce various shapes. Parts produced using MPF suffer from geometrical defects such as wrinkling, dimpling and thickness variations. In this paper, a multipoint forming process using a novel mesh-type elastic cushion was proposed in order to improve the quality of the deformed sheet and to minimise the developed defects. Finite element modelling (FEM) and design of experiments (DoE) were used to study the influence of the mesh-type elastic cushion parameters such as the type and the size of the mesh, and the thickness of the cushion on the wrinkling, deviation and thickness variations of the deformed sheet. The results showed that using elastic cushion with square meshes of a size of 3.5 mm and a thickness of 3 mm reduced the wrinkling from 3.18 to 1.98 mm, while the thickness variation improved from 98 to 19 μm. Finally, the deviation from target shape reduced from 1.7848 to 0.0358 mm.

show abstract

“…13 The forming parameters such as the hardness and thickness of the elastic cushion, blank holder force, coefficient of friction and radius of curvature were investigated and optimised to improve the quality of parts using MPF. 14 Forming force measurements are essential for the investigations of MPF processes to avoid defects and improve forming precision. To detect forming forces on individual pins in MPF tools within a narrow working area requires sensors with high specifications.…”

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Measurement of forces on multi-point forming tools using fibre Bragg grating sensors

Elghawail

Pham

Huang

et al. 2019

Proceedings of the Institution of Mechanical Engineers, Part B:

View full text Add to dashboard Cite

Multi-point forming uses forces applied to a tool, comprising of multiple pins set at different heights, to form sheet metal for panelling in white goods, automotive bodywork, aircraft frames and so on. The use of multiple pins allows for rapid change over and flexibility in the tool making it suitable for small-batch and prototype component manufacture. To explore the relationship between ‘springback’ of the sheet metal on release from the tool, and the applied pin force, it is first necessary to understand and measure the forming forces. This article presents a novel method of measuring forming forces on individual pins in a multi-point forming tool using fibre Bragg grating sensors, monitoring the elastic strain on the selected pins during the forming process. The operating principles behind forming force measurements using fibre Bragg gratings are introduced and a relationship is developed between springback in the formed part after the final unloading and the forming force as measured on selected individual pins under different compression ratios (30%, 40%, 50% and 60%) of the elastic cushion between the tips of the pins and the workpiece. Experiments were performed to validate the proposed measuring method, and results indicate that forming forces detected by the proposed method correlated well with the results obtained by numerical simulation. This suggests the proposed method has good potential for real-time measurement and monitoring of forming force distribution in multi-point forming tools during the forming process.

show abstract

Experimental research and numerical optimisation of multi-point sheet metal forming implementation using a solid elastic cushion system

Cited by 5 publications

References 8 publications

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

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

Multipoint forming using mesh-type elastic cushion: modelling and experimentation

Measurement of forces on multi-point forming tools using fibre Bragg grating sensors

Contact Info

Product

Resources

About