Tài liệu Machining technology machine tools and operations

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Machining Technology Machine Tools and Operations
CRC_43390_FM.indd i 3/25/2008 5:13:23 PM CRC_43390_FM.indd ii 3/25/2008 5:13:25 PM CRC_43390_FM.indd iii 3/25/2008 5:13:25 PM CRC Press Taylor & Francis Group 6000 Broken Sound Parkway NW, Suite 300 Boca Raton, FL 33487-2742 © 2008 by Taylor & Francis Group, LLC CRC Press is an imprint of Taylor & Francis Group, an Informa business No claim to original U.S. Government works Printed in the United States of America on acid-free paper 10 9 8 7 6 5 4 3 2 1 International Standard Book Number-13: 978-1-4200-4339-6 (Hardcover) This book contains information obtained from authentic and highly regarded sources Reasonable efforts have been made to publish reliable data and information, but the author and publisher cannot assume responsibility for the validity of all materials or the consequences of their use. The Authors and Publishers have attempted to trace the copyright holders of all material reproduced in this publication and apologize to copyright holders if permission to publish in this form has not been obtained. If any copyright material has not been acknowledged please write and let us know so we may rectify in any future reprint Except as permitted under U.S. Copyright Law, no part of this book may be reprinted, reproduced, transmitted, or utilized in any form by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying, microfilming, and recording, or in any information storage or retrieval system, without written permission from the publishers. For permission to photocopy or use material electronically from this work, please access www.copyright.com (http:// www.copyright.com/) or contact the Copyright Clearance Center, Inc. (CCC) 222 Rosewood Drive, Danvers, MA 01923, 978-750-8400. CCC is a not-for-profit organization that provides licenses and registration for a variety of users. For organizations that have been granted a photocopy license by the CCC, a separate system of payment has been arranged. Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation without intent to infringe. Library of Congress Cataloging-in-Publication Data Youssef, Helmi A. Machining technology : machine tools and operations / Helmi A. Youssef, Hassan El-Hofy. p. cm. Includes bibliographical references and index. ISBN 978-1-4200-4339-6 (hardback : alk. paper) 1. Machining. 2. Machine-tools. I. El-Hofy, Hassan. II. Title. TJ1185.Y68 2008 671.3’5--dc22 2008008302 Visit the Taylor & Francis Web site at http://www.taylorandfrancis.com and the CRC Press Web site at http://www.crcpress.com CRC_43390_FM.indd iv 3/25/2008 5:13:25 PM To our grandsons and granddaughters, Omar, Youssef, Nour, Anourine, Fayrouz, and Yousra CRC_43390_FM.indd v 3/25/2008 5:13:25 PM CRC_43390_FM.indd vi 3/25/2008 5:13:26 PM Contents Preface ............................................................................................................................................xix Acknowledgments ........................................................................................................................ xxiii Editors ............................................................................................................................................xxv List of Symbols ............................................................................................................................xxvii List of Acronyms ....................................................................................................................... xxxiii Chapter 1 Machining Technology.................................................................................................1 1.1 1.2 1.3 1.4 Introduction ...............................................................................................................................1 History of Machine Tools .........................................................................................................1 Basic Motions in Machine Tools...............................................................................................5 Aspects of Machining Technology ........................................................................................... 5 1.4.1 Machine Tool .................................................................................................................6 1.4.2 Workpiece Material ....................................................................................................... 9 1.4.3 Machining Productivity .................................................................................................9 1.4.4 Accuracy and Surface Integrity................................................................................... 10 1.4.5 Product Design for Economical Machining ................................................................ 10 1.4.6 Environmental Impacts of Machining ........................................................................ 10 1.5 Review Questions .................................................................................................................... 10 References ........................................................................................................................................ 10 Chapter 2 Basic Elements and Mechanisms of Machine Tools .................................................. 11 2.1 Introduction ............................................................................................................................. 11 2.2 Machine Tool Structures ......................................................................................................... 13 2.2.1 Light- and Heavy-weight Constructions ...................................................................... 17 2.3 Machine Tool Guideways ........................................................................................................ 18 2.3.1 Sliding Friction Guideways ......................................................................................... 18 2.3.2 Rolling Friction Guideways ......................................................................................... 21 2.3.3 Externally Pressurized Guideways .............................................................................. 22 2.4 Machine Tool Spindles............................................................................................................ 23 2.4.1 Spindle Bearings ......................................................................................................... 23 2.4.2 Selection of Spindle-Bearing Fit .................................................................................25 2.4.3 Sliding Friction Spindle Bearing ................................................................................. 27 2.5 Machine Tool Drives ...............................................................................................................28 2.5.1 Stepped Speed Drives..................................................................................................28 2.5.1.1 Belting ...........................................................................................................28 2.5.1.2 Pick-Off Gears .............................................................................................. 30 2.5.1.3 Gearboxes...................................................................................................... 30 2.5.1.4 Stepping of Speeds According to Arithmetic Progression ........................... 31 2.5.1.5 Stepping of Speeds According to Geometric Progression ............................ 32 2.5.1.6 Kinetic Calculations of Speed Gearboxes .................................................... 35 2.5.1.7 Application of Pole-Changing Induction Motors.......................................... 35 2.5.1.8 Feed Gearboxes ............................................................................................ 37 2.5.1.9 Preselection of Feeds and Speeds ................................................................. 39 vii CRC_43390_FM.indd vii 3/25/2008 5:13:26 PM viii Contents 2.5.2 Stepless Speed Drives .................................................................................................40 2.5.2.1 Mechanical Stepless Drives .........................................................................40 2.5.2.2 Electrical Stepless Speed Drive ................................................................... 42 2.5.2.3 Hydraulic Stepless Speed Drive ................................................................... 43 2.6 Planetary Transmission ..........................................................................................................44 2.7 Machine Tool Motors ............................................................................................................. 45 2.8 Reversing Mechanisms ........................................................................................................... 45 2.9 Couplings and Brakes .............................................................................................................46 2.10 Reciprocating Mechanisms .................................................................................................... 48 2.10.1 Quick-Return Mechanism ........................................................................................... 48 2.10.2 Whitworth Mechanism ................................................................................................ 50 2.10.3 Hydraulic Reciprocating Mechanism ......................................................................... 50 2.11 Material Selection and Heat Treatment of Machine Tool Components ................................. 51 2.11.1 Cast Iron ...................................................................................................................... 51 2.11.2 Steels............................................................................................................................ 52 2.12 Testing of Machine Tools ....................................................................................................... 53 2.13 Maintenance of Machine Tools .............................................................................................. 55 2.13.1 Preventive Maintenance .............................................................................................. 56 2.13.2 Corrective Maintenance .............................................................................................. 56 2.13.3 Reconditioning ............................................................................................................ 56 2.14 Review Questions ................................................................................................................... 57 References ........................................................................................................................................ 57 Chapter 3 General-Purpose Machine Tools ................................................................................ 59 3.1 3.2 Introduction ............................................................................................................................ 59 Lathe Machines and Operations ............................................................................................. 59 3.2.1 Turning Operations...................................................................................................... 59 3.2.2 Metal Cutting Lathes ...................................................................................................60 3.2.2.1 Universal Engine Lathes ...............................................................................60 3.2.2.2 Other Types of General-Purpose Metal Cutting Lathes ............................... 69 3.3 Drilling Machines and Operations ......................................................................................... 70 3.3.1 Drilling and Drilling Allied Operations ..................................................................... 70 3.3.1.1 Drilling Operation......................................................................................... 70 3.3.1.2 Drilling Allied Operations ............................................................................ 71 3.3.2 General-Purpose Drilling Machines ........................................................................... 74 3.3.2.1 Bench-Type Sensitive Drill Presses .............................................................. 74 3.3.2.2 Upright Drill Presses..................................................................................... 74 3.3.2.3 Radial Drilling Machines ............................................................................. 76 3.3.2.4 Multispindle Drilling Machines.................................................................... 76 3.3.2.5 Horizontal Drilling Machines for Drilling Deep Holes ............................... 77 3.3.3 Tool Holding Accessories of Drilling Machines ......................................................... 77 3.3.4 Work-Holding Devices Used on Drilling Machines ................................................... 79 3.4 Milling Machines and Operations .......................................................................................... 82 3.4.1 Milling Operations ...................................................................................................... 82 3.4.1.1 Peripheral Milling ......................................................................................... 82 3.4.1.2 Face Milling ..................................................................................................84 3.4.2 Milling Cutters ............................................................................................................84 CRC_43390_FM.indd viii 3/25/2008 5:13:26 PM Contents ix 3.4.3 General-Purpose Milling Machines ........................................................................... 86 3.4.3.1 Knee-Type Milling Machines ....................................................................... 86 3.4.3.2 Vertical Bed-Type Milling Machines............................................................ 88 3.4.3.3 Planer-Type Milling Machine ....................................................................... 88 3.4.3.4 Rotary-Table Milling Machines .................................................................... 89 3.4.4 Holding Cutters and Workpieces on Milling Machines .............................................90 3.4.4.1 Cutter Mounting ............................................................................................90 3.4.4.2 Workpiece Fixturing ..................................................................................... 91 3.4.5 Dividing Heads ...........................................................................................................94 3.4.5.1 Universal Dividing Heads .............................................................................94 3.4.5.2 Modes of Indexing ........................................................................................ 95 3.5 Shapers, Planers, and Slotters and Their Operations ..............................................................99 3.5.1 Shaping, Planing, and Slotting Processes....................................................................99 3.5.1.1 Determination of vcm in Accordance with the Machine Mechanism.......... 101 3.5.2 Shaper and Planer Tools ............................................................................................ 102 3.5.3 Shapers, Planers, and Slotters.................................................................................... 103 3.5.3.1 Shapers ........................................................................................................ 103 3.5.3.2 Planers ......................................................................................................... 105 3.5.3.3 Slotters......................................................................................................... 107 3.6 Boring Machines and Operations ........................................................................................ 107 3.6.1 Boring ........................................................................................................................ 107 3.6.2 Boring Tools .............................................................................................................. 108 3.6.2.1 Types of Boring Tools ................................................................................. 108 3.6.2.2 Materials of Boring Tools ........................................................................... 109 3.6.3 Boring Machines ....................................................................................................... 109 3.6.3.1 General-Purpose Boring Machines............................................................. 109 3.6.3.2 Jig Boring Machines ................................................................................... 110 3.7 Broaching Machines and Operations .................................................................................... 111 3.7.1 Broaching .................................................................................................................. 111 3.7.1.1 Advantages and Limitations of Broaching ................................................. 112 3.7.2 The Broach Tool ........................................................................................................ 113 3.7.2.1 Tool Geometry and Configuration .............................................................. 113 3.7.2.2 Broach Material .......................................................................................... 116 3.7.2.3 Broach Sharpening ...................................................................................... 116 3.7.3 Broaching Machines .................................................................................................. 116 3.7.3.1 Horizontal Broaching Machines ................................................................. 117 3.7.3.2 Vertical Broaching Machines...................................................................... 118 3.7.3.3 Continuous Horizontal Surface Broaching Machines ................................ 118 3.8 Grinding Machines and Operations ...................................................................................... 119 3.8.1 Grinding Process ....................................................................................................... 119 3.8.2 Grinding Wheels ....................................................................................................... 122 3.8.2.1 Manufacturing Characteristics of Grinding Wheels .................................. 122 3.8.2.2 Grinding Wheel Geometry ......................................................................... 127 3.8.2.3 Mounting and Balancing of Grinding Wheels and Safety Measures ......... 127 3.8.2.4 Turning and Dressing of Grinding Wheels................................................. 130 3.8.3 Grinding Machines .................................................................................................... 131 3.8.3.1 Surface Grinding Machines and Related Operations ................................. 132 3.8.3.2 External Cylindrical Grinding Machines and Related Operations ............ 133 3.8.3.3 Internal Grinding Machines and Related Operations ................................. 136 3.8.3.4 Centerless Grinding Machines and Related Operations ............................. 137 CRC_43390_FM.indd ix 3/25/2008 5:13:26 PM x Contents 3.9 Microfinishing Machines and Operations ............................................................................ 141 3.9.1 Honing ....................................................................................................................... 141 3.9.1.1 Process Capabilities .................................................................................... 142 3.9.1.2 Machining Parameters ................................................................................ 144 3.9.1.3 Honing Machines ........................................................................................ 145 3.9.2 Superfinishing (Microhoning) ................................................................................... 145 3.9.3 Lapping ...................................................................................................................... 147 3.9.3.1 Machining Parameters ................................................................................ 147 3.9.3.2 Lapping Machines ....................................................................................... 148 3.10 Review Questions .................................................................................................................. 154 References ...................................................................................................................................... 156 Chapter 4 Thread Cutting ......................................................................................................... 157 4.1 Introduction ........................................................................................................................... 157 4.2 Thread Cutting ...................................................................................................................... 159 4.2.1 Cutting Threads on the Lathe.................................................................................... 160 4.2.2 Thread Chasing ......................................................................................................... 163 4.2.3 Thread Tapping ......................................................................................................... 164 4.2.4 Die Threading............................................................................................................ 168 4.2.4.1 Die Threading Machines ............................................................................ 169 4.2.4.2 Die Threading Performance........................................................................ 172 4.2.5 Thread Milling .......................................................................................................... 172 4.2.6 Thread Broaching ...................................................................................................... 175 4.3 Thread Grinding ................................................................................................................... 175 4.3.1 Center-Type Thread Grinding ................................................................................... 175 4.3.2 Centerless Thread Grinding ...................................................................................... 177 4.4 Review Questions .................................................................................................................. 178 References ...................................................................................................................................... 179 Chapter 5 Gear Cutting Machines and Operations................................................................... 181 5.1 Introduction ........................................................................................................................... 181 5.2 Forming and Generating Methods in Gear Cutting.............................................................. 183 5.2.1 Gear Cutting by Forming .......................................................................................... 184 5.2.1.1 Gear Milling................................................................................................ 184 5.2.1.2 Gear Broaching ........................................................................................... 188 5.2.1.3 Gear Forming by a Multiple-Tool Shaping Head ........................................ 189 5.2.1.4 Straight Bevel Gear Forming Methods ....................................................... 190 5.2.2 Gear Cutting by Generation ...................................................................................... 190 5.2.2.1 Gear Hobbing .............................................................................................. 190 5.2.2.2 Gear Shaping with Pinion Cutter ................................................................ 198 5.2.2.3 Gear Shaping with Rack Cutter ..................................................................202 5.2.2.4 Cutting Straight Bevel Gears by Generation ..............................................202 5.3 Selection of Gear Cutting Method ........................................................................................207 5.4 Gear Finishing Operations ....................................................................................................207 5.4.1 Finishing Gears Prior to Hardening ..........................................................................207 5.4.1.1 Gear Shaving ...............................................................................................207 5.4.1.2 Gear Burnishing .......................................................................................... 211 5.4.2 Finishing Gears After Hardening.............................................................................. 212 5.4.2.1 Gear Grinding ............................................................................................. 212 5.4.3 Gear Lapping ............................................................................................................. 214 CRC_43390_FM.indd x 3/25/2008 5:13:26 PM Contents xi 5.5 Review Questions and Problems ........................................................................................... 215 References ...................................................................................................................................... 215 Chapter 6 Turret and Capstan Lathes ....................................................................................... 217 6.1 6.2 6.3 6.4 Introduction ........................................................................................................................... 217 Difference Between Capstan and Turret Lathes ................................................................... 217 Selection and Application of Capstan and Turret Lathes ..................................................... 219 Principal Elements of Capstan and Turret Lathes ................................................................ 219 6.4.1 Headstock and Spindle Assembly ............................................................................. 220 6.4.2 Carriage/Cross-Slide Unit ......................................................................................... 221 6.4.3 Hexagonal Turret ....................................................................................................... 221 6.4.3.1 Manually Controlled Machines .................................................................. 222 6.4.3.2 Automatically Controlled Headstock Turret Lathes ................................... 222 6.4.4 Cross-Sliding Hexagonal Turret ................................................................................ 223 6.5 Turret Tooling Setups ............................................................................................................ 223 6.5.1 Job Analysis ............................................................................................................... 223 6.5.2 Tooling Layout........................................................................................................... 226 6.6 Review Questions .................................................................................................................. 232 References ...................................................................................................................................... 232 Chapter 7 Automated Lathes .................................................................................................... 233 7.1 7.2 7.3 7.4 Introduction ........................................................................................................................... 233 Degree of Automation and Production Capacity .................................................................. 234 Classification of Automated Lathes ...................................................................................... 235 Semiautomatic Lathes ........................................................................................................... 237 7.4.1 Single-Spindle Semiautomatics ................................................................................. 237 7.4.2 Multispindle Semiautomatics .................................................................................... 239 7.5 Fully Automatic Lathes......................................................................................................... 241 7.5.1 Single-Spindle Automatic.......................................................................................... 241 7.5.1.1 Turret Automatic Screw Machine ............................................................... 241 7.5.1.2 Swiss-Type Automatic ................................................................................. 252 7.5.2 Horizontal Multispindle Bar and Chucking Automatics ........................................... 256 7.5.2.1 Special Features of Multispindle Automatics ............................................ 256 7.5.2.2 Characteristics of Parallel- and Progressive-Action Multispindle Automatic .............................................................................. 258 7.5.2.3 Operation Principles and Constructional Features of a Progressive Multispindle Automatic ...........................................................260 7.6 Design and Layout of Cams for Fully Automatics ...............................................................266 7.6.1 Planning a Sequence of Operation and a Tooling Layout ......................................... 267 7.6.2 Cam Design ............................................................................................................... 268 7.7 Review Questions and Problems ........................................................................................... 283 References ......................................................................................................................................284 Chapter 8 Numerical Control and Computer Numerical Control Technology ......................... 285 8.1 Introduction ........................................................................................................................... 285 8.2 Coordinate System ................................................................................................................290 8.2.1 Machine Tool Axes for NC .......................................................................................290 8.2.2 Quadrant Notation ..................................................................................................... 292 8.2.3 Point Location ........................................................................................................... 292 8.2.4 Zero Point Location ................................................................................................... 293 CRC_43390_FM.indd xi 3/25/2008 5:13:27 PM xii Contents 8.2.5 Setup Point................................................................................................................. 293 8.2.6 Absolute and Incremental Positioning....................................................................... 293 8.3 Machine Movements in Numerical Control Systems ........................................................... 294 8.4 Interpolation ......................................................................................................................... 296 8.5 Control of Numerical Control Machine Tools ...................................................................... 297 8.6 Components of Numerical Control Machine Tools .............................................................. 299 8.7 Tooling for Numerical Control Machines ............................................................................302 8.8 Numerical Control Machine Tools ....................................................................................... 305 8.9 Input Units ............................................................................................................................308 8.10 Forms of Numerical Control Instructions ............................................................................ 310 8.11 Program Format .................................................................................................................... 311 8.12 Feed and Spindle Speed Coding ........................................................................................... 312 8.12.1 Feed Rate Coding ...................................................................................................... 312 8.12.2 Spindle Speed Coding ............................................................................................... 314 8.13 Features of Numerical Control Systems ............................................................................... 314 8.14 Part Programming ................................................................................................................ 316 8.15 Programming Machining Centers ........................................................................................ 320 8.15.1 Planning the Program ................................................................................................ 320 8.15.2 Canned Cycles ........................................................................................................... 322 8.16 Programming Turning Centers ............................................................................................. 328 8.16.1 Planning the Program ................................................................................................ 328 8.16.2 Canned Turning Cycles ............................................................................................. 331 8.17 Computer-Assisted Part Programming................................................................................. 334 8.17.1 Automatically Programmed Tools Language............................................................ 334 8.17.2 Programming Stages ................................................................................................. 337 8.18 CAD/CAM Approach to Part Programming ........................................................................ 339 8.18.1 Computer-Aided Design ............................................................................................ 339 8.18.2 Computer-Aided Manufacturing ............................................................................... 339 8.19 Review Questions .................................................................................................................340 References ...................................................................................................................................... 343 Chapter 9 Hexapods and Machining Technology ..................................................................... 345 9.1 9.2 9.3 Introduction .......................................................................................................................... 345 Historical Background .......................................................................................................... 345 Hexapod Mechanism and Design Features ..........................................................................348 9.3.1 Hexapod Mechanism .................................................................................................348 9.3.2 Design Features ......................................................................................................... 349 9.3.2.1 Hexapods of Telescopic Struts (Ingersoll System)...................................... 349 9.3.2.2 Hexapods of Ball Screw Struts (Hexel and Geodetic System) ................... 352 9.4 Hexapod Constructional Elements ....................................................................................... 354 9.4.1 Strut Assembly .......................................................................................................... 354 9.4.2 Sphere Drive .............................................................................................................. 354 9.4.3 Bifurcated Balls ......................................................................................................... 356 9.4.4 Spindles ..................................................................................................................... 357 9.4.5 Articulated Head ....................................................................................................... 359 9.4.6 Upper Platform .......................................................................................................... 359 9.4.7 Control System .......................................................................................................... 361 9.5 Hexapod Characteristics ....................................................................................................... 362 9.6 Manufacturing Applications ................................................................................................. 366 CRC_43390_FM.indd xii 3/25/2008 5:13:27 PM Contents xiii 9.7 Review Questions ................................................................................................................. 368 References ...................................................................................................................................... 369 Chapter 10 Machine Tool Dynamometers ................................................................................ 371 10.1 10.2 Introduction ......................................................................................................................... 371 Design Features of Dynamometers ..................................................................................... 371 10.2.1 Rapier Parameters for Dynamometer Design ....................................................... 372 10.2.2 Main Requirements of a Good Dynamometer ...................................................... 373 10.3 Dynamometers Based on Displacement Measurements ..................................................... 374 10.3.1 Two-Channel Cantilever (Chisholm) Dynamometer ............................................ 374 10.3.2 Two-Channel-Slotted Cantilever Dynamometer................................................... 374 10.4 Dynamometers Based on Strain Measurement ................................................................... 375 10.4.1 Strain Gauges and Wheatstone Bridges ................................................................ 375 10.4.2 Cantilever Strain Gauge Dynamometers .............................................................. 377 10.4.3 Octagonal Ring Dynamometers............................................................................ 378 10.4.3.1 Strain Rings and Octagonal Ring Transducers ..................................... 378 10.4.3.2 Turning Dynamometer .......................................................................... 382 10.4.3.3 Surface Plunge-Cut Grinding Dynamometer ....................................... 384 10.4.3.4 Milling Dynamometers ......................................................................... 384 10.5 Piezoelectric (Quartz) Dynamometers ................................................................................ 384 10.5.1 Principles and Features ......................................................................................... 384 10.5.2 Typical Piezoelectric Dynamometers ................................................................... 386 10.6 Review Questions ................................................................................................................ 389 References ...................................................................................................................................... 390 Chapter 11 Nontraditional Machine Tools and Operations ........................................................ 391 11.1 11.2 11.3 11.4 CRC_43390_FM.indd xiii Introduction ......................................................................................................................... 391 Classification of Nontraditional Machining Processes ....................................................... 392 Jet Machines and Operations .............................................................................................. 392 11.3.1 Abrasive Jet Machining......................................................................................... 392 11.3.1.1 Process Characteristics and Applications ............................................. 392 11.3.1.2 Work Station of Abrasive Jet Machining .............................................. 395 11.3.1.3 Process Capabilities .............................................................................. 396 11.3.2 Water Jet Machining (Hydrodynamic Machining) ............................................... 397 11.3.2.1 Process Characteristics and Applications ............................................. 397 11.3.2.2 Equipment of WJM ............................................................................... 399 11.3.2.3 Process Capabilities .............................................................................. 401 11.3.3 Abrasive Water Jet Machining .............................................................................402 11.3.3.1 Process Characteristics and Applications .............................................402 11.3.3.2 Abrasive Water Jet Machining Equipment ...........................................405 11.3.3.3 Process Capabilities ..............................................................................409 Ultrasonic Machining Equipment and Operation ............................................................... 410 11.4.1 Definitions, Characteristics, and Applications...................................................... 410 11.4.2 USM Equipment ................................................................................................... 413 11.4.2.1 Oscillating System and Magnetostriction Effect .................................. 413 11.4.2.2 Tool Feeding Mechanism ...................................................................... 418 11.4.3 Design of Acoustic Horns .................................................................................... 419 11.4.3.1 General Differential Equation............................................................... 419 11.4.3.2 Design of the Cylindrical Stepped Acoustic Horns (A(x) = C)............ 421 11.4.3.3 Design of Exponential Acoustic Horns (A(x) = A0e−2hx) ...................... 421 3/25/2008 5:13:27 PM xiv Contents 11.4.4 Process Capabilities .............................................................................................. 430 11.4.4.1 Stock Removal Rate .............................................................................. 430 11.4.4.2 Accuracy and Surface Quality .............................................................. 432 11.4.5 Recent Developments ............................................................................................ 433 11.5 Chemical Machining ........................................................................................................... 434 11.5.1 Chemical Milling .................................................................................................. 435 11.5.2 Photochemical Machining (Spray Etching) .......................................................... 441 11.6 Electrochemical Machines and Operations ........................................................................ 445 11.6.1 Process Characteristics and Applications ............................................................ 445 11.6.2 Elements of Electrochemical Machining .............................................................. 447 11.6.2.1 Tool........................................................................................................ 447 11.6.2.2 Workpiece .............................................................................................449 11.6.2.3 Electrolyte ............................................................................................449 11.6.3 ECM Equipment ...................................................................................................449 11.6.4 Process Capabilities .............................................................................................. 451 11.7 Electrochemical Grinding Machines and Operations ........................................................ 453 11.8 Electrical Discharge Machines and Operations.................................................................. 454 11.8.1 Process Characteristics and Applications ............................................................ 454 11.8.2 ED Sinking Machine............................................................................................. 458 11.8.3 EDM-Spark Circuits (Power Supply Circuits) ......................................................460 11.8.3.1 Resistance-Capacitance Circuit ...........................................................460 11.8.3.2 Transistorized Pulse Generator Circuits ............................................... 462 11.8.4 EDM-Tool Electrodes............................................................................................ 463 11.8.5 Process Capabilities ..............................................................................................464 11.8.6 Electrical Discharge Milling.................................................................................465 11.8.7 Electrodischarge Wire Cutting ............................................................................468 11.9 Electron Beam Machining Equipment and Operations ...................................................... 470 11.9.1 Process Characteristics and Applications .............................................................. 470 11.9.2 Electron Beam Machining Equipment .................................................................. 471 11.9.3 Process Capabilities ................................................................................................ 474 11.10 Laser Beam Machining Equipment and Operations .......................................................... 475 11.10.1 Process Characteristics ........................................................................................... 475 11.10.2 Types of Lasers ...................................................................................................... 477 11.10.2.1 Pyrolithic and Photolithic Lasers ........................................................... 477 11.10.2.2 Industrial Lasers ..................................................................................... 477 11.10.2.3 Laser Beam Machining Operations ....................................................... 478 11.10.3 LBM Equipment ..................................................................................................... 481 11.10.4 Applications and Capabilities ................................................................................. 483 11.11 Plasma Arc Cutting Systems and Operations ..................................................................... 485 11.11.1 Process Characteristics ........................................................................................... 485 11.11.2 Plasma Arc Cutting Systems .................................................................................. 486 11.11.3 Applications and Capabilities of Plasma Arc Cutting ............................................ 486 11.12 Review Questions ................................................................................................................ 488 References ...................................................................................................................................... 492 Chapter 12 Environment-Friendly Machine Tools and Operations .......................................... 495 12.1 Introduction ......................................................................................................................... 495 12.2 Traditional Machining ........................................................................................................ 498 12.2.1 Cutting Fluids ......................................................................................................... 501 12.2.1.1 Classification of Cutting Fluids ............................................................... 501 CRC_43390_FM.indd xiv 3/25/2008 5:13:28 PM Contents xv 12.2.1.2 Selection of Cutting Fluids ......................................................................502 12.2.1.3 Evaluation of Cutting Fluids ...................................................................502 12.2.2 Hazard Ranking of Cutting Fluids ......................................................................... 503 12.2.3 Health Hazards of Cutting Fluids ...........................................................................504 12.2.4 Cryogenic Cooling ..................................................................................................504 12.2.5 Ecological Machining............................................................................................. 505 12.3 Nontraditional Machining Processes ................................................................................... 510 12.3.1 Chemical Machining .............................................................................................. 510 12.3.2 Electrochemical Machining.................................................................................... 512 12.3.3 Electrodischarge Machining................................................................................... 514 12.3.3.1 Protective Measures ............................................................................... 516 12.3.4 Laser Beam Machining .......................................................................................... 516 12.3.5 Ultrasonic Machining ............................................................................................. 519 12.3.5.1 Electromagnetic Field .............................................................................. 520 12.3.5.2 Ultrasonic Waves ..................................................................................... 520 12.3.5.3 Abrasives Slurry ...................................................................................... 520 12.3.5.4 Contact Hazards ...................................................................................... 521 12.3.5.5 Other Hazards.......................................................................................... 521 12.3.6 Abrasive Jet Machining .......................................................................................... 521 12.4 Review Questions................................................................................................................. 523 References ...................................................................................................................................... 524 Chapter 13 Design for Machining ............................................................................................. 525 13.1 Introduction.......................................................................................................................... 525 13.1.1 General Design Rules ............................................................................................. 525 13.2 General Design Recommendations .................................................................................... 526 13.3 Design for Machining by Cutting ....................................................................................... 528 13.3.1 Turning ................................................................................................................... 528 13.3.1.1 Economic Production Quantities............................................................. 529 13.3.1.2 Design Recommendations for Turning.................................................... 530 13.3.1.3 Dimensional Control ............................................................................... 535 13.3.2 Drilling and Allied Operations............................................................................... 535 13.3.2.1 Economic Production Quantities............................................................. 536 13.3.2.2 Design Recommendations for Drilling and Allied Operations............... 536 13.3.2.3 Dimensional Control ............................................................................... 539 13.3.3 Milling .................................................................................................................... 539 13.3.3.1 Design Recommendations ....................................................................... 539 13.3.3.2 Dimensional Factors and Tolerances ....................................................... 542 13.3.4 Shaping, Planing, and Slotting................................................................................ 542 13.3.4.1 Design Recommendations ....................................................................... 542 13.3.4.2 Dimensional Control ............................................................................... 543 13.3.5 Broaching................................................................................................................544 13.3.5.1 Design Recommendations .......................................................................544 13.3.5.2 Dimensional Factors ................................................................................ 549 13.3.5.3 Recommended Tolerances ....................................................................... 550 13.3.6 Thread Cutting........................................................................................................ 550 13.3.6.1 Design Recommendations ....................................................................... 550 13.3.6.2 Dimensional Factors and Tolerances ....................................................... 551 13.3.7 Gear Cutting ........................................................................................................... 552 13.3.7.1 Design Recommendations ....................................................................... 552 13.3.7.2 Dimensional Factors ................................................................................ 554 CRC_43390_FM.indd xv 3/25/2008 5:13:28 PM xvi Contents 13.4 Design for Grinding ............................................................................................................. 554 13.4.1 Surface Grinding .................................................................................................... 554 13.4.1.1 Design Recommendations ....................................................................... 554 13.4.1.2 Dimensional Control ............................................................................... 556 13.4.2 Cylindrical Grinding .............................................................................................. 556 13.4.2.1 Design Recommendations ....................................................................... 556 13.4.2.2 Dimensional Factors ................................................................................ 557 13.4.3 Centerless Grinding ................................................................................................ 557 13.4.3.1 Design Recommendations ....................................................................... 558 13.4.3.2 Dimensional Control ............................................................................... 559 13.5 Design for Finishing Processes............................................................................................ 559 13.5.1 Honing .................................................................................................................... 559 13.5.2 Lapping ................................................................................................................... 560 13.5.3 Superfinishing ......................................................................................................... 561 13.6 Design for Chemical and Electrochemical Machining ....................................................... 561 13.6.1 Chemical Machining .............................................................................................. 561 13.6.1.1 Design Recommendations ....................................................................... 561 13.6.1.2 Dimensional Factors and Tolerances ....................................................... 563 13.6.2 Electrochemical Machining.................................................................................... 563 13.6.2.1 Design Recommendations .......................................................................564 13.6.2.2 Dimensional Factors ................................................................................ 566 13.6.3 Electrochemical Grinding ...................................................................................... 566 13.6.3.1 Design Recommendations ....................................................................... 566 13.6.3.2 Dimensional Factors ................................................................................ 567 13.7 Design for Thermal Machining ........................................................................................... 567 13.7.1 Electrodischarge Machining................................................................................... 567 13.7.1.1 Design Recommendations ....................................................................... 567 13.7.1.2 Dimensional Factors ................................................................................ 568 13.7.2 Electron Beam Machining ...................................................................................... 568 13.7.3 Laser Beam Machining .......................................................................................... 569 13.8 Design for Ultrasonic Machining ........................................................................................ 570 13.9 Design for Abrasive Jet Machining ..................................................................................... 571 13.10 Review Questions................................................................................................................. 572 References ...................................................................................................................................... 573 Chapter 14 Accuracy and Surface Integrity Realized by Machining Processes ........................ 575 14.1 14.2 14.3 14.4 14.5 Introduction.......................................................................................................................... 575 Surface Texture .................................................................................................................... 575 Surface Quality and Functional Properties ......................................................................... 577 Surface Integrity .................................................................................................................. 579 Surface Effects by Traditional Machining........................................................................... 582 14.5.1 Chip Removal Processes......................................................................................... 582 14.5.2 Grinding.................................................................................................................. 583 14.6 Surface Effects by Nontraditional Machining ..................................................................... 587 14.6.1 Electrochemical and Chemical Machining ........................................................... 590 14.6.2 Thermal Nontraditional Processes ......................................................................... 591 14.6.2.1 Electrodischarge Machining ................................................................... 591 14.6.2.2 Laser Beam Machining ........................................................................... 596 14.6.2.3 Electron Beam Machining ...................................................................... 597 14.6.2.4 Plasma Beam Machining (PBM)............................................................. 598 CRC_43390_FM.indd xvi 3/25/2008 5:13:28 PM Contents xvii 14.6.2.5 Electroerosion Dissolution Machining .................................................... 598 14.6.2.6 Electrochemical Discharge Grinding ...................................................... 598 14.6.3 Mechanical Nontraditional Processes .................................................................... 599 14.7 Reducing Distortion and Surface Effects in Machining...................................................... 599 14.8 Review Questions................................................................................................................. 601 References ...................................................................................................................................... 601 Chapter 15 Automated Manufacturing System .........................................................................603 15.1 Introduction..........................................................................................................................603 15.2 Manufacturing Systems .......................................................................................................605 15.3 Flexible Automation-Flexible Manufacturing Systems .......................................................609 15.3.1 Elements of Flexible Manufacturing System ......................................................... 610 15.3.2 Limitations of Flexible Manufacturing System...................................................... 611 15.3.3 Features and Characteristics ................................................................................... 611 15.3.4 New Developments in Flexible Manufacturing System Technology ..................... 611 15.4 Computer Integrated Manufacturing ................................................................................... 612 15.4.1 Computer-Aided Design ......................................................................................... 615 15.4.2 Computer-Aided Process Planning......................................................................... 616 15.4.3 Computer-Aided Manufacturing ............................................................................ 617 15.5 Lean Production–Just-in-Time Manufacturing Systems ..................................................... 617 15.5.1 Steps for Implementing the IMPS Lean Production .............................................. 618 15.5.2 Just-in-Time and Just-in-Case Production .............................................................. 619 15.6 Adaptive Control .................................................................................................................. 620 15.7 Smart Manufacturing and Artificial Intelligence ................................................................ 622 15.7.1 Expert Systems ....................................................................................................... 622 15.7.2 Machine Vision ....................................................................................................... 623 15.7.3 Artificial Neural Networks ..................................................................................... 623 15.7.4 Natural-Language Systems ..................................................................................... 624 15.7.5 Fuzzy Logic (Fuzzy Models) .................................................................................. 624 15.8 Factory of the Future ........................................................................................................... 624 15.9 Concluding Remarks Related to Automated Manufacturing .............................................. 625 15.10 Review Questions................................................................................................................. 625 References ...................................................................................................................................... 626 Index .............................................................................................................................................. 627 CRC_43390_FM.indd xvii 3/25/2008 5:13:28 PM CRC_43390_FM.indd xviii 3/25/2008 5:13:29 PM Preface This book provides a comprehensive description of machining technologies related to metal shaping by material removal techniques, from the basic to the most advanced, in today’s industrial applications. It is a fundamental textbook for undergraduate students enrolled in production, materials and manufacturing, industrial, and mechanical engineering programs. Students from other disciplines can also use this book while taking courses in the area of manufacturing and materials engineering. It should be also useful to graduates enrolled in high-level machining technology courses and professional engineers working in the field of manufacturing industry. The book covers the technologies, machine tools, and operations of several machining processes. The treatment of the different subjects has been developed from the basic principles of machining processes, machine tool elements, and control systems, and extends to ecological machining and the most recent machining technologies, including nontraditional methods and hexapod machine tools. Along with the fundamentals of the conventional and modern machine tools and processes, the book presents environmentalfriendly machine tools and operations; design for machining, accuracy, and surface integrity realized by machining operations; machining data; and solved examples, problems, and review questions, which are very useful for undergraduate students and manufacturing engineers facing shop floor problems. The book is written in 15 chapters, describing for the first time in one book the fundamentals, basic elements, and operations of general-purpose machine tools used for the production of cylindrical and flat surfaces by turning, drilling and reaming, shaping and planing, and milling processes. Special-purpose machines and operations used for thread cutting, gear cutting, and broaching processes are also dealt with. Semiautomatic, automatic, NC and CNC machine tools, operations, tooling, mechanisms, accessories, and work fixation are discussed. Abrasion and abrasive finishing machine tools and operations such as grinding, honing, superfinishing, and lapping are described. Modern machine tools and operations, dynamometers, and hexapod machine tools and processes are described. Design for accurate and economic machining, ecological machining, levels of accuracy, and surface finish attained by machining methods are also presented. OUTLINE OF THE BOOK In Chapter 1, the history and progress of machining, aspects of machining technology, and the basic motions of machine tools are introduced. Classification of machine tools and operations in addition to the basic motions of machining operations are also given. Chapter 2 introduces the design considerations and requirements of machine tools, including basic elements such as beds, structures, frames, guideways, spindles and shafts, stepped and stepless drives, planetary transmission, machine tool motors, couplings, and brakes. Material selection and heat treatment of machine tool elements, and the testing and maintenance of machine tools are also discussed. Chapter 3 covers general-purpose metal cutting machine tools including lathes, drilling, reaming, jig boring machines, milling machines, and the machine tools of a reciprocating nature such as shapers, planers, and slotters. Machine tool elements, mechanisms, tooling, accessories, and operations are also explained. Chapter 3 also presents abrasion machine tools, including grinding and surface finishing machines and processes. Chapter 4 describes the different types and applications of commonly used screw threads. Thread machining by cutting and grinding methods are described, together with thread cutting machines and cutting tools. In Chapter 5, common types of gears are listed and their applications described. Gear production by machining methods that include cutting, grinding, and lapping are described, together with their corresponding machine tools and operations. xix CRC_43390_FM.indd xix 3/25/2008 5:13:29 PM
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