Keywords: machining allowance, volume minimization, iron casting, machine tool, simulation, contactless three-dimensional scanning, photogrammetry.

This paper demonstrates the problems of machining allowances for the mass minimization of iron castings using machine tools by means of simulation methods. Modern machine tool design development predominantly aims at the improvement of their operating efficacy and accuracy while simultaneously reducing cost [1] but unfortunately, in most cases these three factors are mutually exclusive [2]. Therefore, cost reduction, should be sought in areas bearing no direct influence on machine tool efficiency and accuracy.

In this paper the authors propose a new machining allowance volume minimization system for machine tool casting. Thus the implied reduction of swarf by-production promises to bring about considerable reductions in energy consumption, an alleviation of machining difficulties, and a decrease in tool overexploitation [3], directly influencing production expenditure. Thus it is proposed to replace the arduous cast marking out procedure with an innovative implementation of visual measurement technology. Introducing TRITOP and Atos (GOM) measuring systems it is postulated that the critical advantage of cast geometry scanning resulted in rapid acquisition of virtual models of the casts investigated [4,5]. Appropriate processing of the obtained scan images allows their comparison with the construction model designs of individual machine tool body elements [6,7].

There are two ways of determining machining allowances and mass minimization. According to the individual methods of machining allowance for mass minimization, each cast is subjected to the machining allowance for volume minimization individually [8]. As opposed to the individual method, the global mode of surplus minimization involves creating a virtual system of all scanned casts comprising a given machine tool, inter-connected by a chain of dimensions [9].

1

M. Berg, S. Keller, "MAHO. Training literature. CNC 432", AG Pfronten, 1991.

2

K. Ehmann, S. Kapoor, R. Devor, I. Lazoglu, "Machining process modelling", Journal of Manufacturing Science and Engineering, 119, 655-663, 1997. doi:10.1115/1.2836805

3

K. Mrozek, A. Gessner, "Optimization of machining allowances of large size iron castings", Advances in Science and Technology, 6, 96-103, 2011.

4

ATOS GOM II, User information, catalogues, 2011.

5

W. Cuypers, N. Van Gestel, A. Voet, J.-P. Kruth, J. Mingneau, P. Bleys, "Optical measurement techniques for mobile and large-scale dimensional metrology", Optics and Lasers in Engineering, 47, 292-300, 2009. doi:10.1016/j.optlaseng.2008.03.013

6

M. Wieczorowski, M. Rucinski, R. Koteras, "Application of optical scanning for measurement of castings and cores", Archives of Foundry Engineering, 10, 265-268, 2010.

7

K. Galanulis, C. Reich, J. Thesing, D. Winter, "Optical Digitizing by ATOS for Press Parts and Tools", Internal publication, GOM, Braunschweig, 2005.

8

A. Gessner, Patent application no. P-390852 (31.03.2010), "Method for preparing cast iron for machining with minimized machining allowances", (in Polish).

9

K. Mrozek, Patent application nr P-396737 (24.10.2011), "Sposób przygotowania zespolu montazowego odlewów do obróbki z globalna minimalizacja naddatków obróbkowych" (in Polish).

purchase the full-text of this paper (price £20)

go to the previous paper
go to the next paper
return to the table of contents
return to the book description
purchase this book (price £50 +P&P)