Open AccessAnalysis of the Mechanics of Cutting by a Cylindrical Drill with a Bridge
Author(s) -
L D Olenin
Publication year - 2011
Publication title -
izvestiâ mgtu "mami"
Language(s) - English
Resource type - Journals
eISSN - 2949-1428
pISSN - 2074-0530
DOI - 10.17816/2074-0530-69955
Subject(s) - drill , drilling , mechanics , strain hardening exponent , mechanical engineering , isotropy , deformation (meteorology) , structural engineering , engineering , materials science , physics , composite material , quantum mechanics
The article presents the results of analytical study of mechanics of formation of cylindrical holes in solid material by a rotating tool. The analysis is performed by the energy method using the extreme positions of deformation mechanics at following assumptions. The processed material is considered isotropic, having strain hardening, that corresponds to the conditions of full cold deformation. In addition, it is assumed that the contact friction submits to the Coulomb law, that is proportional to the normal pressure at the contact, the hardening curve on a dedicated section approximated by a linear function. Two variants of cutting are investigated: the tool with the drill web, that has a negative rake, and the tool with the corrected drill web. It is shown that the traditional drill with a drill web is not an effective tool. Optimization of geometry of a drill web provides repeated reduction of axial force. The physical equations for calculation of power parameters of drilling based on the actual geometry of a cutting part of the tool, and also its central part named a drill web, are given.