On the Variability of Tool Wear and Life at Disparate Operating Parameters

Authors: S. E. Oraby, A.M. Alaskari

Abstract:

The stochastic nature of tool life using conventional discrete-wear data from experimental tests usually exists due to many individual and interacting parameters. It is a common practice in batch production to continually use the same tool to machine different parts, using disparate machining parameters. In such an environment, the optimal points at which tools have to be changed, while achieving minimum production cost and maximum production rate within the surface roughness specifications, have not been adequately studied. In the current study, two relevant aspects are investigated using coated and uncoated inserts in turning operations: (i) the accuracy of using machinability information, from fixed parameters testing procedures, when variable parameters situations are emerged, and (ii) the credibility of tool life machinability data from prior discrete testing procedures in a non-stop machining. A novel technique is proposed and verified to normalize the conventional fixed parameters machinability data to suit the cases when parameters have to be changed for the same tool. Also, an experimental investigation has been established to evaluate the error in the tool life assessment when machinability from discrete testing procedures is employed in uninterrupted practical machining.

Keywords: Machinability, tool life, tool wear, wear variability

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1328152

References:

[1] Y. Kwon and W. Fischer, "A novel approach to quantifying tool wear and tool life measurements for optimal tool management," International Journal of Machine Tools and Manufacture, vol. 43, no. 4, pp. 359-368, 2003.
[2] Tool life testing with single-point turning tool, B94.55M, (The British Standards Institution, BSI Britsh Standards, 839 Chiswick High Road, London W4 4AL, England, 1985.
[3] R. A. Etheridge and T. C. Hsu, "The specific wear rate and its application to the assessment of machinability," Annals of the CIRP, vol. 18, no. 1, pp. 107-118, 1970.
[4] M. Kronenberg, "Replacing the Taylor formula by a new tool life equation," International Journal of Machine Tool Design and Research, vol. 10, no. 2, pp. 193-202, 1970.
[5] B. N. Colding and W. Koning, "Validity of the Taylor equation in metal cutting," Annals of the CIRP, vol. 19, no. 4, pp. 793-812, 1971.
[6] T. R. Chandrupatta, "An alternative method for the determination of tool life equations," in Proc. 26 th International Machine Tools Design and Research (MATADOR) Conf., pp, 359-361, Manchester (UMIST), England, 1986.
[7] V. P. Astakhov, "The assessment of cutting tool wear," International Journal of Machine Tools & Manufacture, vol. 44, no. 6, pp. 637-647, 2004.
[8] J. A. Arsecularatne, L. C. Zhang and C. Montross, "Wear and tool life of tungsten carbide, PCBN and PCD cutting tools," International Journal of Machine Tools & Manufacture, vol. 46, no. 5, pp. 482-491, 2006.
[9] K. Uehara, "New attempts for short time tool life testing," Annals of the CIRP, vol. 22, no. 1, pp. 23-24, 1973.
[10] T. Sata, "Rapid tool life tests by means of irradiated carbide cutting tools," Journal of Japanese Precision Engineering, vol. 24, pp. 453-460, 1985.
[11] Wu Chen 1988. "A new rapid wear test for cutting tools," in Poc. 27 th International Machine Tools Design & Research (MATADOR) Conf., pp. 261-265, Manchester (UMIST), England, 1988.
[12] Y. Koren, "A variable cutting speed method for tool life evaluation," in Proc. the 4th Conf. on Production Engineering, pp. 530-534 Tokyo, Japan, 1980.
[13] K. Jemieliniak, M. Szafarczyk and J. Zawistowski, "Difficulties in tool life predicting when turning with variable cutting parameters," Annals of the CIRP, vol. 34, no. 1, pp. 113-116, 1985.
[14] K. Nagasaka and F. Hashimoto, "Tool wear prediction and economics in machining stepped parts," International Journal of Machine Tools & Manufacture, vol. 28, no. 4, pp. 569-576, 1988.
[15] D. S. Ermer and S. M. Wu, "The effect of experimental error on the determination of the optimum metal cutting conditions," Transactions ASME, Journal of Engineering for Industry, Series B, vol. 89, no. 2, pp.315-322, 1966.
[16] M. Y. Friedman and N. Zlatin, "Variability of tool life as a function of its mean value," in Proc. the North American Manufacturing Research Conference NAMRC-II, pp.128-138. Madison, WI, USA, 1974.
[17] D. A. Axinte, W. Belluco and L. D. Chiffre, "Reliable tool life measurements in turning - an application to cutting fluid efficiency evaluation," International Journal of Machine Tools & Manufacture, vol. 41, no. 7, pp. 1003-1014, 2001.
[18] Tool-Life Testing with Single-Point Turning Tools, ISO 3685, International Organization for Standardization (ISO), 1993.
[19] S. E. Oraby and D. R. Hayhurst, "Tool life determination based on the measurement of war and tool force ratio variation," International Journal of Machine Tools & Manufacture, vol. 44, no. 12, pp. 1261- 1269, 2004.