CIRP Annals Online sorted by Year and Volume




A key issue in product life cycle : disassembly
F. Jovane (1), L. Alting (1), A. Armillotta, W. Eversheim (1), K. Feldmann (2), G. Seliger (2), N. Roth (2)  
STC A,  42/2/1993,  P.651
Keywords: Assembly, Disassembly, Recycling
Abstract : Incoming environmental legislation is expected to impose recycling activities on industrial and consumer product manufacturers. Disassembly of used products is needed in order to make recycling economically viable in the current state of the an of reprocessing technology, thus avoiding the future high disposal costs. This paper gives an overview of disassembly research at universities, research centers and industrial companies, pointing out ongoing topics and trends for future activities. Among them, major attention has been paid to basic technological development, product design (design for disassembly), process design (selection of disassembly strategy and automation level) and system design (configuration of manual and automated disassembly facilities, design of disassembly tools). It is also shown how the emerging life cycle concept can be fully exploited to develop suitable ways of dealing with information related to environmental protection and resource optimization. A result of the survey is that further development on disassembly of existing products (technology, planning at process and system level) is needed to allow future products to be designed with recycling considerations in mind.


Recent developments in chip control research and applications
I.S. Jawahir (2), C.A. Van Luttervelt (1)  
STC C,  42/2/1993,  P.659
Keywords: Chip Formation, Chips, Chip Control, Chip Breakers, Chip Removal
Abstract : During the 1990 CIRP General Assembly in Berlin a working group on Chip Control was formed within the STC -"Cutting", with a view to evaluating and sharing the present knowledge on chip formation and chip control and promoting new research in this area. To date, about 40 researchers have made more than 60 contributions at six chip control working group meetings. Among these presentations, several contributions really provided fresh insights dealing with new and innovative research methods. The working group also provided a framework for international cooperative work, enabling exchange of information and coordinated research collaboration. The group placed a greater emphasis on the practical value of knowledge on chip control for industrial applications. This paper presents the major results of this cooperative work covering modeling of the chip formation process for chip flow; curl and breaking; means of chip breaking, including experimental as well as the knowledge-based systems approach; and a summary of future directions in research and applications.

 STC Dn 

Product modelling
F.L. Krause (2), F. Kimura (2), T. Kjellberg (2), S.C.Y. Lu (2), L. Alting (1), H.A. ElMaraghy (1), W. Eversheim (1), K. Iwata (1), N.P. Suh (1), V.A. Tipnis (2), M. Weck (1)  
STC Dn,  42/2/1993,  P.695
Keywords: Computer-Aided Design, Product Development, Modeling
Abstract : One of the most challenging tasks in the engineering profession is to develop new products that have the shortest lead-time. highest quality and lowest cost with optimal life-cycle consideration. The issue of product modeling is at the center of various new product development paradigms designed to meet this challenge, and, therefore, has received major attentions from application and research communities. Due to the fast developments of computer and information technologies and the increasing demands of competitiveness and productivity, the scopes and approaches of product modeling have evolved rapidly in recent years. This paper presents an overview of the state-of-the-art and practice of product modeling in terms of product models and process chains, and suggests some important issues for further investigation.


Advanced techniques for die and mold manufacturing
T. Altan (1), B.W. Lilly, J.P. Kruth (1), W. Koenig (1), H.K. Toenshoff (1), C.A. Van Luttervelt (1)  
STC E,  42/2/1993,  P.707
Keywords: Die, Mold
Abstract : Die and mold manufacturing represents a significant area of production technology since it influences the feasibility and economics of producing a very large number of discrete components. Modern die manufacturing includes just about all aspects of manufacturing: part design, geometry handling and transfer, die design. process modeling, prototype production, control of dimensional and surface quality as well as advanced mechanical, electrical, and electrochemical machining methods. This paper, prepared with input from various CIRP colleagues, attempts to review the latest advances and practical applications in the field


Recent development in auto-body panel forming technology
T. Nakagawa (1)  
STC F,  42/2/1993,  P.717
Keywords: Sheet Metal, Formability, Deep Drawing, Forming Techniques, Laser Beam Welding, Simulation
Abstract : Auto-body panel forming is one of the most important manufacturing processes in automotive industry. Intensive efforts have been made continuously for the improvement of panel quality and productivity and for the reduction of manufacturing cost. Forming process itself does not change so much but the whole panel manufacturing system is gradually changing by introducing the surrounding advanced technologies. This paper deals with the recent innovative developments in the fields of forming materials, blank preparation, control of forming conditions, forming tool design and manufacturing and computer simulation of forming process. Contributions for preparing this survey are received from T. Altan, E. Doege, M. Geiger, K. Lange and A. Schey. The author would like to extend his sincere gratitude to automotive industries, Toyota, Nissan and Honda for their valuable contributions to prepare the paper.


Abrasive machining in the future
I. Inasaki (1), H.K. Toenshoff (1), T.D. Howes (2)  
STC G,  42/2/1993,  P.723
Keywords: Abrasives, Grinding, Grinding Wheels, Grinding Fluids, Machine Tools
Abstract : Although abrasive machining is a centuries-old technology, it continues to play an important role in industry. The extremely small scale of chips produced and the self-sharpening of grinding wheels are key advantages of abrasive machining and should be taken advantage of in future efforts to develop abrasive machining technologies. The most recent developments in abrasive machining are reviewed pointing out problems to be solved for their practical applications in the near future. Developing technologies reviewed in the paper relate to 1. technologies for making abrasive grinding wheels, 2. high-precision machining, 3. heavy-duty machining, 4. implementation of intelligent abrasive machining, 5. use of computer simulation to understand abrasive processes, and 6. environmental aspects of abrasive processes. It is concluded that promising abrasive technologies of the future should include grinding wheels with ultrafine grits, molecular dynamics surface integrity assessment techniques, high-speed abrasive machining with CBN, autonomous machining system implementing intelligent control and advanced monitoring systems, and coolant free grinding.


High speed machining
J. Tlusty (1)  
STC M,  42/2/1993,  P.733
Keywords: Machining, Machine Tools, High Speed
Abstract : Applications of High Speed Milling to face milling of cast iron with silicon nitride tools, to end milling of aluminum aircraft structures, to end milling of titanium fan blades and to end milling of hardened steel dies are described. A case of High Speed Grinding of gears is also introduced. The problem of loss of Process Damping is dealt with as well as the use of spindle speed regulation for improving stability. The various aspects of HST discussed are the spindle and guideway design, feed drives for fast cornering, lightweight structures.


Evolution and future perspectives of CAPP
H.A. ElMaraghy (1)  
STC O,  42/2/1993,  P.739
Keywords: Computer-Aided Process Planning, Computer Integrated Manufacturing, Product/Process Modelling and Planning
Abstract : Modem manufacturing is characterized by low volume, high variety production and close tolerance high quality products. Computer Integrated Manufacturing (CIM) is recognized as an effective platform for increasing manufacturing competitiveness. Computer Aided Process Planning is an essential key for achieving CIM. The integration of design, computer aided process planning (CAPP) and production planning and control (PPC) is becoming essential especially in a concurrent engineering environment where many product life cycle factors are of concern. An overview of the major development thrust in CAPP is presented along with some of the evolving trends and challenges such as rapid, generic, dynamic and/or distributed process planning. Related issued of quality and evolving standards are also discussed.


Scales vs laserinterferometers - Performance and comparison of two measuring systems
H. Kunzmann (1), T. Pfeifer, J. Flaegge  
STC P,  42/2/1993,  P.753
Keywords: Accuracy, Displacement Measurements, Gratings, Laser Interferometers
Abstract : Scales and laser interferometers both are linear displacement measuring systems (LBS). It is the performance of the LBS that limits the accuracy of servo-positioning machine tools and/or measuring instruments. The traditional systems for this purpose (besides lead-screws) have been graduated scales. Since the invention of the Here gasser laserinterferometry has been an attractive alternative to scales. The performance of both systems are partially very similar, partially very different. In this paper metrology relevant capabilities of both systems are described and compared.


Low pressure synthesis of diamond coatings
H.E. Hintermann (1), A.K. Chattopadhyay  
STC S,  42/2/1993,  P.769
Keywords: Surfaces, Diamond Coatings, Manufacturing Processes
Abstract : In part 1 of this paper a concise r351sum351 is given on the present understanding of the reigning mechanisms of COD low pressure diamond synthesis, in particular of nucleation and early growth. The formation and involvement of atomic hydrogen and hydro255carbon radicals is essential for growing diamond films; they are the determining active and interactive species. In part 2 the po255tential of COD diamond in mechanical, especially tool applications, is treated. A state-of-the-art overview of current industrial uses, capabilities and limitations of COD diamond products is presented and discussed. Part 3 deals with an entirely new applica255tion of COD diamond with definite industrial potential, i.e. with thin film diamond sensors. The feasibility of such devices has been shown; nevertheless, to make the product commercially viable, depends on the successful development of an industrially economic process technology - hence, presents a strong CIRP related challenge.