THE EFFECTS OF PUNCH SPEED ON THE FORGING LOAD OF HOT PRECISION BEVEL GEAR FORGING
Abstract
The mass production bevel gears is mainly realized by precision forging process. The process can be carried out cold, warm or hot conditions by using various forging presses (hydraulic or mechanical presses and HERF machines). The process cycle time is changing with the type of forging press (i.e. the speed of punch). During hot forging, the hot billet is in contact with the relatively colder die and heat is transferred to the environment. Therefore, the billet temperature is changing during deformation and the processing time is an effective parameter of the temperature distribution of the billet. The flow stress of the material and the forging load are increasing with reducing billet temperature. In this study, the effect of punch speed on the forging load were investigated by the finite element method. To simulate different forging presses, various punch speeds were chosen as 0.001 m/s, 0.01 m/s, 0.1 m/s, 1 m/s. and 10 m/s. In accordance with these punch speeds, the temperature distribution of the billet and the forging loads were determined. The results show that the temperature drop of the billet and the forging load are decreasing with the increasing punch speed. So that forging with HERF machines is advantageous than the hydraulic and mechanical presses in the precision hot forging process of bevel gears.
Keywords
Bevel gear forging,forging,finite element method,heat treatment
References
- Behrens, B.A., Doege, E., Reinsch, S., Telkamp, K., Daehndel, H., and Specker, A. (2007) Precision forging processes for high-duty automotive components. J. Mater. Process. Technol.
- Eyercioglu, O., Dean, T.., and Wlaton, D. (1996) Precision Forging of Gears. Int. Mach. Des. Prod. Conf.
- Eyercioglu, O., Dean, T.., and Walton, D. (1994) Dimensional accuracy of hot precision forged spur gears. Int. Gearing Conf.
- Yilmaz, N.F., and Eyercioglu, O. (2018) Near Net Shape Spur Gear Forging Using Concave Preform. Mechanics, 24 (2), 268–277.
- Doege, E., and Nägele, H. (1994) FE Simulation of the Precision Forging Process of Bevel Gears. CIRP Ann., 43 (1), 241–244.
- Szentmihali, V., Lange, K., Tronel, Y., Chenot, J.-L., and Ducloux, R. (1994) 3-D finite-element simulation of the cold forging of helical gears. J. Mater. Process. Technol., 43 (2–4), 279–291.
- Mamalis, A.G., Manolakos, D.E., and Baldoukas, A.K. (1996) Simulation of the precision forging of bevel gears using implicit and explicit FE techniques. J. Mater. Process. Technol., 57 (1–2), 164–171.
- Song, J.H., and Im, Y.T. (2007) Process design for closed-die forging of bevel gear by finite element analyses. J. Mater. Process. Technol.
- Kim, S.-Y., and Im, Y.-T. (2002) Three-dimensional finite element analysis of non-isothermal shape rolling. J. Mater. Process. Technol., 127 (1), 57–63.
- Kim, S.-Y., Tsuruoka, K., and Yamamoto, T. (2014) Effect of Forming Speed in Precision Forging Process Evaluated Using CAE Technology and High Performance Servo-press Machine. Procedia Eng., 81, 2415–2420.
