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Effect of Global and Local Stiffness on Blankholder Pressure in Draw Die Forming
Technical Paper
2001-01-1138
ISSN: 0148-7191, e-ISSN: 2688-3627
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Sector:
Event:
SAE 2001 World Congress
Language:
English
Abstract
This work investigates the effect of elastic deformation of the press and die in a double action press on system performance during draw die forming. A simple linear elastic model of the complete press system was developed to show that the relative stiffness of system components controls blankholder force variation during the stroke. Calibration of the analytical model with data taken from a production press shows that the simple model explains real global system behaviour very well; and that varying system compliances can desensitise the press system to changes affecting the binder gap during the stroke. The experimental data suggests that real press and tool systems do not have an appropriate combination of system compliance, which causes large variations in blankholder force during the stroke. This model will be a useful tool for die designers and process engineers for assessing the potential impact of blankholder force variation during die design. It can also be included in finite element forming simulation models.
The main focus of this work is the global model, however it is important to recognise that local structural stiffness of the stamping tools also has an important effect on restraining force variation around the binders. Contact pressure contour plots generated from a finite element model of a production blankholder are used to illustrate the significance of local structural stiffness variation. A simple model is developed to explain this result, which agrees with information available from the tryout process for that tool.
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Citation
Dingle, M., Hodgson, P., and Cardew-Hall, M., "Effect of Global and Local Stiffness on Blankholder Pressure in Draw Die Forming," SAE Technical Paper 2001-01-1138, 2001, https://doi.org/10.4271/2001-01-1138.Also In
References
- Karima M. “Practical Application of Process Simulation in Stamping,” Journal of Materials Processing Technology 46 309 320 1994
- Doege E. Sommer N. “Blank-holder Pressure and Blank-holder Layout in Deep Drawing of Thin Sheet Metal,” Proceedings of 2nd International Conference on Technology of Plasticity 11 1987
- Karima M. “Understanding Blank Holder Effect on Formability of Sheet Metal Stampings,” SAE Technical Paper Series 890347 1989
- Lange K. Handbook of Metal forming Dearborn, Michigan Society of Manufacturing Engineers 1985
- Siegert K. Wagner S. Ziegler M. “Closed Loop Control of the Friction Force. Deep Drawing Process.,” Journal of Materials Processing Technology 126 133 1997
- Dingle M.E. Hodgson P.D. Cardew-Hall M.J. “Analysis of the Elastic Behaviour of the Press System in Draw Die Forming,” presented at Innovations in Processing and Manufacturing of Sheet Metals New Orleans 2001