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Manufacturing Planning and Control (MPC) systems have attracted great interest in recent years. T... more Manufacturing Planning and Control (MPC) systems have attracted great interest in recent years. Teaching of this subject however is challenging because of the difficulty of providing appropriate examples in an academic environment. This paper describes a business game developed by a leading automotive components company. The objective of the game is to illustrate the benefits of reducing complexity within manufacturing systems in simplifying planning and control. The paper describes the development process for the game and provides detailed playing instructions. Finally, the paper reviews the use of the game in both an industrial and an academic context.
… : Proceedings of the …, 1985
The ever-increasing development and implementation of expensive advanced machines have made the s... more The ever-increasing development and implementation of expensive advanced machines have made the study of machining economics increasingly important. Machining economics is to a great extent about making use of production resources most efficiently and at the lowest possible cost. Since the cost and time of machining are sensitive to the cutting conditions, optimum values have to be determined before a part is put into production. The optimum cutting conditions in this context are those that do not violate any of the constraints that may apply on the process and satisfy the economic criterion. The main objectives of this thesis are to investigate the methodologies and to develop a logical algorithm for predicting the constrained optimum cutting conditions in oblique machining with nose radius tools so that the production cost/time can be calculated and minimised. Based on a variable flow stress machining theory, a method has been developed for predicting cutting forces, stresses, temperatures, etc. which are then used to check process constraints such as machine power, tool plastic deformation and built-up edge formation, from a knowledge of the work material properties and the cutting conditions. 2.1 Optimisation Criteria, Constraints and Strategies 11 2.2 Analytical Studies of Machining Process 2.2.1 The Orthogonal Machining Theory 2.3 Oblique Machining with Nose Radius Tools 2.3.1 Chip Flow Direction and Equivalent Cutting Edge 2.3.2 Chip Flow Angle due to the Effect of Nose Radius 2.3.3 Modified Tool Angles and Equivalent Cutting Edge 40 2.4 Cutting Forces and Tool Temperatures in Oblique Machining Chapter Three. Modelling of the Optimisation of cutting conditions 3.1 Economic Consideration and Objective Functions of a Single-Pass Turning Operation 3.2 Optimisation Procedure 3.3 Constraints , iv 3.3.1 Tool Plastic Deformation 50 3.3.2 Machine Tool Torque/Power 51 3.3.3 Minimum and Maximum Tool Life Values 53 3.3.4 Available Feeds and Speeds of the Machine Tool Used, as well as the Minimum and Maximum Feeds/Depths for Tool and Workpiece 53 3.3.5 Built-up Edge Formation 54 3.4 Prediction of Cutting Forces, Temperatures, Stresses, etc. in Oblique Machining With Nose Radius Tools 56 3.5 Prediction of Tool Life in Oblique Machining 57 Chapter Four. Prediction of Cutting Conditions Giving Plastic Deformation of the Tools in Oblique Machining 59 4.1 Introduction 4.2 Review of Previous Work 4.3 Calculation of Stresses Inside the Cutting Edge of a Tool 4.3.1 Stress Analysis in the Cutting Edge region of a Tool 67 4.3.2 Stresses on the Tool Flank-Work Interface 71 4.4 Prediction of Cutting Conditions Giving Plastic Deformation of the Cutting Edge of a Tool 72 4.4.1 Loading Conditions of a Tool 4.4.2 Prediction Methodology 4.4.3 Comparison Between Predicted and Experimental Plastic Deformation Conditions in Approximately Orthogonal Machining 4.4.4 Prediction of Plastic Deformation Conditions in Oblique Machining 4.4.4.1 Determination of High Temperature Shear Strength Data for the Tool Material 4.4.4.2 The Predicted Results 4.5 Experimental Procedure 4.5.1 Methods Used for Determining Plastic Deformation
issues
Manufacturing Planning and Control (MPC) systems have attracted great interest in recent years. T... more Manufacturing Planning and Control (MPC) systems have attracted great interest in recent years. Teaching of this subject however is challenging because of the difficulty of providing appropriate examples in an academic environment. This paper describes a business game developed by a leading automotive components company. The objective of the game is to illustrate the benefits of reducing complexity within manufacturing systems in simplifying planning and control. The paper describes the development process for the game and provides detailed playing instructions. Finally, the paper reviews the use of the game in both an industrial and an academic context.
… : Proceedings of the …, 1985
The ever-increasing development and implementation of expensive advanced machines have made the s... more The ever-increasing development and implementation of expensive advanced machines have made the study of machining economics increasingly important. Machining economics is to a great extent about making use of production resources most efficiently and at the lowest possible cost. Since the cost and time of machining are sensitive to the cutting conditions, optimum values have to be determined before a part is put into production. The optimum cutting conditions in this context are those that do not violate any of the constraints that may apply on the process and satisfy the economic criterion. The main objectives of this thesis are to investigate the methodologies and to develop a logical algorithm for predicting the constrained optimum cutting conditions in oblique machining with nose radius tools so that the production cost/time can be calculated and minimised. Based on a variable flow stress machining theory, a method has been developed for predicting cutting forces, stresses, temperatures, etc. which are then used to check process constraints such as machine power, tool plastic deformation and built-up edge formation, from a knowledge of the work material properties and the cutting conditions. 2.1 Optimisation Criteria, Constraints and Strategies 11 2.2 Analytical Studies of Machining Process 2.2.1 The Orthogonal Machining Theory 2.3 Oblique Machining with Nose Radius Tools 2.3.1 Chip Flow Direction and Equivalent Cutting Edge 2.3.2 Chip Flow Angle due to the Effect of Nose Radius 2.3.3 Modified Tool Angles and Equivalent Cutting Edge 40 2.4 Cutting Forces and Tool Temperatures in Oblique Machining Chapter Three. Modelling of the Optimisation of cutting conditions 3.1 Economic Consideration and Objective Functions of a Single-Pass Turning Operation 3.2 Optimisation Procedure 3.3 Constraints , iv 3.3.1 Tool Plastic Deformation 50 3.3.2 Machine Tool Torque/Power 51 3.3.3 Minimum and Maximum Tool Life Values 53 3.3.4 Available Feeds and Speeds of the Machine Tool Used, as well as the Minimum and Maximum Feeds/Depths for Tool and Workpiece 53 3.3.5 Built-up Edge Formation 54 3.4 Prediction of Cutting Forces, Temperatures, Stresses, etc. in Oblique Machining With Nose Radius Tools 56 3.5 Prediction of Tool Life in Oblique Machining 57 Chapter Four. Prediction of Cutting Conditions Giving Plastic Deformation of the Tools in Oblique Machining 59 4.1 Introduction 4.2 Review of Previous Work 4.3 Calculation of Stresses Inside the Cutting Edge of a Tool 4.3.1 Stress Analysis in the Cutting Edge region of a Tool 67 4.3.2 Stresses on the Tool Flank-Work Interface 71 4.4 Prediction of Cutting Conditions Giving Plastic Deformation of the Cutting Edge of a Tool 72 4.4.1 Loading Conditions of a Tool 4.4.2 Prediction Methodology 4.4.3 Comparison Between Predicted and Experimental Plastic Deformation Conditions in Approximately Orthogonal Machining 4.4.4 Prediction of Plastic Deformation Conditions in Oblique Machining 4.4.4.1 Determination of High Temperature Shear Strength Data for the Tool Material 4.4.4.2 The Predicted Results 4.5 Experimental Procedure 4.5.1 Methods Used for Determining Plastic Deformation