Analytical Calculation of the True Equivalent Chip Thickness for Cutting Tools and its Influence on the Calculated Tool Life


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A majority of the established systems for determination and optimization of cutting data are based on Woxén’s equivalent chip thickness, heW. In metal cutting theory and models, the equivalent chip thickness is of vital importance when the depth-of-cut ap is in the same order or smaller than the nose radius r. Woxén made considerable simplifications in his chip area model, that form the basis for calculations of the equivalent chip thickness. Basic mathematical solutions, e.g. describing the chip area on circular inserts, are lacking. This article describes the geometrical implications when machining with round inserts. The error in Woxén’s equivalent chip thickness is largest when the depth-of-cut is less than ¼ of the nose radius and are up to 40 % wrong for some combinations of cutting data in the finishing range. The presented results explain the difficulties in getting a good validity in the models used to calculate tool life in finishing machining. The error leads to an underrating of the tool load in many machining situations



Edited by:

Mustafizur Rahman, Erry Yulian Triblas Adesta, Mohammad Yeakub Ali, A.N. Mustafizul Karim, Md. Abdul Maleque, Hazleen Anuar, Tasnim Firdaus Mohamed Ariff, NMohammad Iqbal, Noorasikin Samat and Noor Azlina Hassan




J. E. Ståhl and F. Schultheiss, "Analytical Calculation of the True Equivalent Chip Thickness for Cutting Tools and its Influence on the Calculated Tool Life", Advanced Materials Research, Vol. 576, pp. 80-86, 2012

Online since:

October 2012




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