Evaluation of tooth profile changes of symmetric and asymmetric spur gear forging dies due to shrink fit

The compressive pre-stress due to the shrink fitting cause dimensional changes on the tooth profile of the precision gear forging dies. The accuracy of the gear die is directly affecting the accuracy of the final product. Therefore, the dimensional variations due to shrink fit must be pre-determined and the gear tooth profile on the die insert modified accordingly. In this study, the change of tooth profile of the symmetric and asymmetric precision spur gear forging dies because of shrink fitting are analyzed by finite element (FE) method and the results are compared with the experimental ones. Both the (CMM) measurements and the finite element results of gear dies predict much higher radial displacements than the results of the cylindrical approach (Lame Equations). The amount of radial displacements along the tooth profiles of both symmetric and asymmetric gear dies are not uniform and changing from root to tip of the tooth. The radial displacements of the asymmetric gear forging die are higher than the symmetric one.

___

  • [1] B.A. Behrens, E. Doege, S. Reinsch, K. Telkamp, H. Daehndel, A. Specker, Precision forging processes for high-duty automotive components, J. Mater. Process. Technol. 185 (2007) 139–146. doi:10.1016/j.jmatprotec.2006.03.132.
  • [2] O. Eyercioglu, Developments and performance analyses of precision forged spur gears, University of Birmingham, 1995.
  • [3] O. Eyercioglu, T.. Dean, D. WaLton, Precision Forging of Gears, in: Int. Mach. Des. Prod. Conf., 1996.
  • [4] T. Dean, The net-shape forming of gears, Mater. Des. 21 (2000) 271–278. doi:10.1016/S0261-3069(99)00074-6.
  • [5] O. Eyercioglu, Precision Forging of Asymmetric Spur Gears, Sci. Technol. Res. Counc. Turkey-MAG 217M063. (2018).
  • [6] N.F. Yilmaz, O. Eyercioglu, Near net shape spur gear forging using concave preform, Mechanika. 24 (2018) 268–277. doi:10.5755/j01.mech.24.2.19334.
  • [7] B. Parsons, B.N. Cole, Paper 20: A Generalized Approach to the Optimum Design of Short Composite Cylinders:, doi:10.1243/PIME_CONF_1967_182_084_02. Http://Dx.Doi.Org/10.1243/PIME_CONF_1967_182_084_02. (2016).
  • [8] G. Lamé, Lecons sur la théorie mathématique de l’Elasticite des Corps Solide, Paris, Courcier, Bachelier, Imprimeur-Libraire, 1852.
  • [9] O. Eyercioglu, T.A. Dean, Design and manufacture of precision gear forging dies, Proc. CIRP Int. Conf. Des. Prod. Dies Molds. (1997) 311–316.
  • [10] M.A. Kutuk, O. Eyercioglu, N. Yildirim, A. Akpolat, Finite element analysis of a cylindrical approach for shrink-fit precision gear forging dies, Proc. Inst. Mech. Eng. Part C J. Mech. Eng. Sci. 217 (2003) 677–685. doi:10.1243/095440603321919590.
  • [11] O. Eyercioglu, M.A. Kutuk, N.F. Yilmaz, Shrink fit design for precision gear forging dies, J. Mater. Process. Technol. 209 (2009) 2186–2194. doi:10.1016/j.jmatprotec.2008.05.016.
  • [12] O. Eyercioglu, T. Dean, D. Walton, Dimensional accuracy of hot precision forged spur gears, Int. Gearing Conf. (1994).
  • [13] M.H. Sadeghi, Gear Forging: Mathematical Modeling and Experimental Validation, J. Manuf. Sci. Eng. 125 (2003) 753. doi:10.1115/1.1616952.
  • [14] N.F. Yilmaz, O. Eyercioglu, An integrated computer-aided decision support system for die stresses and dimensional accuracy of precision forging dies, Int. J. Adv. Manuf. Technol. 40 (2009) 875–886. doi:10.1007/s00170-008-1402-z.
  • [15] B.A. Behrens, D. Odening, Process and tool design for precision forging of geared components. Int J Mater Form (2009) 21:125–128. doi.:10.1007/s12289-009-0577-7
  • [16] J.H .Kang, KO Lee, Je J.S., S.S. Kang, Spur gear forging tool manufacturing method considering elastic deformation due to shrink fitting. J Mater Process Technol (2007) 187-188:14–18. doi:10.1016/j.jmatprotec.2006.11.161
  • [17] J.H .Kang, KO Lee, Je J.S., S.S. Kang, New forging tool manufacturing method for spur gear part Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture (2007) 21(11):1601-1606. doi:10.1243/09544054JEM656.
  • [18] F.D. Silveria, L. Schaeffer, Evaluation of different levels of prestressing for cold forging tools by numerical simulation analysis The International Journal of Advanced Manufacturing Technology (2018) 98:2487–2495, doi: 10.1007/s00170-018-2351-9
  • [19] F.D. Silveria, L. Schaeffer, Cold forging tool for gear accuracy grade improvement by a different shrink fitting method REM, Int. Eng. J., Ouro Preto, (2018) 71(4), 593-597, doi: 10.1590/0370-44672017710092
  • [20] Y.S. Lee, J.H. Lee, Experimental and analytical evaluation for elastic deformation behaviors of cold forging tool, J. Mater. Process. Technol. 127 (2002) 73–82.
  • [21] Y.S. Lee, J.H. Lee, Analysis of the elastic characteristics at forging die for the cold forged dimensional accuracy, J. Mater. Process. Technol. 130/131 (2002) 532–539.
  • [22] Y.S. Lee, J.H. Lee, Finite element modeling approaches to the accurate dimensional prediction for a cold-forged part, J. Eng. Manuf. 218 (2004) 1709–1722.
  • [23] B. Zuo, B. Wang, Z. Li, N. Li, J. Lin, An investigation of involute and lead deflection in hot precision forging of gears, Int. J. Adv. Manuf. Technol. 88 (2017) 3017–3030. doi:10.1007/s00170-016-9003-8.
  • [24] P. Pedersen, On Shrink Fit Analysis and Design, Comput. Mech. 37 (2006) 121–130. doi:10.1007/s00466-005-0664-7.
  • [25] O. Eyercioglu, Analysis of Dimensional Variations of Precision Gear Forging Die Geometry Due to Shrink Fit, in: ICEF IV, 4th Int. Conf. Eng. Form. Sci., Amsterdam, 2018.
  • [26] K. Lange, Handbook of metal forming, McGraw-Hill Book Company, 1985. [27] www.suppliersonline.com/propertypages/H13.asp
  • [28] www.azom.com