Manufacturing Automation: Metal Cutting Mechanics, Machine Tool Vibrations, and CNC Design

Abstract

9R15. Manufacturing Automation: Metal Cutting Mechanics, Machine Tool Vibrations, and CNC Design. - Y Altintas (Manuf Autom Lab, Univ of British Columbia, Canada). Cambridge UP, Cambridge, UK. 2000. 286 pp. Softcover. ISBN 0-521-65973-6. $39.95.Reviewed by AA Ber (Dept of Mech Eng, Technion Israel Inst of Tech, Technion City, Haifa 32000, Israel).This reviewer wishes to congratulate the author for writing this book. This combination of the three subjects, Metal Cutting Mechanics, Machine Tool Vibrations, and CNC Design under one roof, is actually done for the first time. Furthermore, integration of these three subjects gives the readers, students (mostly graduates), design engineers, as well as practitioners, a better outlook on the subject dealt with in the book Manufacturing Automation. The book is well written, and the sequence of subjects is perfect. The author was aware that each of the major subjects can fill up a book by itself, and he mentioned it in the introduction. Inserting a Problem Section after each chapter, emphasizing the main points discussed in it, turns the work into a textbook. However, it can also serve as a reference book for engineers and practitioners. Chapter 1 is a general introduction to manufacturing and a short overview of what one will find in this book chapter by chapter. Chapter 2 presents the mechanics of cutting. It is introduced under the most classical approach and written in an orderly and systematic way, except for the section on Milling and Tool Breakage which introduces a refreshing modern approach. Most of the equations are brought in their final form, which is quite acceptable for graduate students, engineers, and practitioners. The nomenclature and symbols are sometimes confusing; the author mixes old American standards with the ISO standards and puts them together in the same equation. This reviewer suggests that in future editions only ISO standard 3002/I through IV be considered. In this chapter, this reviewer missed the roles of Surface Finish and Tolerances in the cutting operations. Tool life is defined geometrically and not in a modern way, namely “The tool terminates its life when it ceases to fulfill its function.” In other words, the tool life ends on reaching the geometrical life (as defined in the book), or when the Surface Finish exceeds the demand and or the part is out of the defined Tolerance. It is a pity that the author did not include a section dealing with tool materials in this chapter. The materials composing the tool play a major role in the mechanics of cutting. For example, the contact length between tool and chip is a function of the tool’s properties (primarily its thermal conductivity) and of other factors.In Chapter 3, the static and dynamic deformation in machining is treated in a very extensive and clear way that even this reviewer (whose field is not dynamics) could understand the factors and problems involved. The analysis presented emphasizes, by sample formulation, prediction of the magnitude and location of static deformation of bar turning and end milling. The section dealing with chatter is most impressively introduced. By introducing modal analysis techniques, the author shows how one can represent a complex machine tool structure using commonly used mathematical expressions and analyze the chatter as well as other sources of vibrations. In Chapter 4, the practical side of manufacturing is discussed. The author introduces the CNC technology and its principles of operation and leads the reader through NC programming of a part. The methodology of NC programming is well presented. All elements involved in CNC are discussed and theoretically supported. In the paragraph on Computer Assisted NC Part Programming, the author succeeded in showing in a compact and very clear form how complicated forms can be dealt with and successfully machined. The basics of Computer-Aided Manufacturing (CAM) is introduced. The author focuses on the teaching aspects of the subject. Chapter 5 contains conventional textbook material. The chapter is well written. The reader is led systematically through the various aspects of the CNC systems. A typical CNC machining center, including all necessary hardware, mechanical, electrical, and hydraulic and their combinations necessary to operate CNC systems, is well described. The various elements required, like machine tool drives, mechanical as well as electrical (and others), are described in detail and accompanied by the relevant formulation on which they are based upon. The mathematical modeling of drive systems is covered both in the time and frequency domain. The author directs some attention to the accuracy of the system. At the end of the chapter, the author presents an example of a design of an Electro-Hydraulic CNC Press Brake. The design contains the various elements of the system and may serve as a guide to the inexperienced reader (mostly students) while dealing with any CNC design. Chapter 6 is mo