MAPPING THE TOTAL VALUE STREAM PP7359_C000.indd 1 5/29/08 9:39:19 AM PP7359_C000.indd 2 5/29/08 9:39:19 AM MAPPING THE TOTAL VALUE STREAM A Comprehensive Guide for Production and Transactional Processes MARK A. NASH AND SHEILA R. POLING PP7359_C000.indd 3 5/29/08 9:39:19 AM Productivity Press Taylor & Francis Group 270 Madison Avenue New York, NY 10016 © 2008 by Taylor & Francis Group, LLC Productivity 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: 978-1-56327-359-9 (Softcover) 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 with- out intent to infringe. Library of Congress Cataloging-in-Publication Data Nash, Mark A., 1959- Mapping the total value stream : a comprehensive guide for production and transactional processes / Mark A. Nash and Sheila R. Poling. p. cm. Includes bibliographical references and index. ISBN 978-1-56327-359-9 (alk. paper) 1. Production engineering. 2. Production management. 3. Process control. I. Poling, Sheila R. II. Title. TS176.N365 2008 658.5--dc22 2007048326 Visit the Taylor & Francis Web site at http://www.taylorandfrancis.com and the Productivity Press Web site at http://www.productivitypress.com PP7359_C000.indd 4 5/29/08 9:39:20 AM Dedication This book is dedicated to the three most important women in my life—Staci, Ally, and Delaney—who continually put up with my time alone to work on projects like this. And a special thank you to Roxie Craycraft who years ago reminded me of the importance of documenting the current state before looking at the future. Mark A. Nash I would like to dedicate this book to all of the people I have worked with in the past, those I work with in the present, and those with whom I will work in the future. By collaborating with a variety of industry experts, I have been able to learn, share, and develop new concepts beyond any I would have created as an individual contributor. This is what continual improvement is truly about. My involvement in this book is a direct result of my friendship with a person I consider to be a Lean Master—Mark Nash. I cannot express the pleasure I have had working on this and other projects with him. Due to our professional alliance, I have learned more about Lean and been given a new perspective and additional insights on quality improvement in general. I hope our successful partnership continues for many years to come. Sheila R. Poling PP7359_C000.indd 5 5/29/08 9:39:20 AM PP7359_C000.indd 6 5/29/08 9:39:20 AM Contents Acknowledgments .................................................................................xiii Introduction ........................................................................................... xv About the Authors ................................................................................. xix 1 The Big Picture … Literally Understanding the Purpose and Power of Value Stream Mapping ......1 Introduction ........................................................................................................ 1 Dissecting a Basic Value Stream Map ............................................................... 2 The Process or Production Flow in a Value Stream Map ......................... 2 The Communication or Information Flow in a Value Stream Map .......... 6 The Timelines and Travel Distances Shown in a Value Stream Map ....... 6 Understanding the Icons Used in Value Stream Mapping ................................ 9 Production versus Transactional Mapping: Understanding the Similarities and Differences .................................................................................................. 9 SECTION I: CurrENT STaTE: uNDErSTaNDINg aND MappINg YOur ExISTINg prOCESS 2 Identifying the Value Stream ............................................................17 Introduction .......................................................................................................17 Option 1: The Matrix Approach ...................................................................... 18 Production Process Matrix ....................................................................... 18 Transactional Process Matrix ................................................................... 21 Option 2: Ready, Aim, Map—Production and Transactional Value Streams ................................................................................................... 25 3 Collecting Basic Information about the Current State..................... 29 Introduction ...................................................................................................... 29 Capturing Basic Information ............................................................................ 29 Begin to Map Your Process ..................................................................... 30 Calculating Takt Time ...................................................................................... 34 4 Documenting Manufacturing (or Production) Process Flow ........... 39 Introduction ...................................................................................................... 39 Identifying and Mapping the Main Flow ........................................................ 40 Map How the Product Moves from One Step to the Next ..................... 42 vii PP7359_C000.indd 7 5/29/08 9:39:20 AM viii n Contents Map Where the Inventory Is .................................................................... 43 Map Where the Operators Are Located .................................................. 44 Putting It All Together .............................................................................. 44 Mapping Subtasks and Parallel Flows ............................................................. 45 Mapping Subtasks ..................................................................................... 45 Mapping Parallel or Alternate Paths ........................................................ 46 Lining Up Process Steps .................................................................................. 47 Aligning the Process Horizontally ........................................................... 48 Aligning the Process Vertically ................................................................ 49 The Power of Speed ........................................................................................ 50 5 Documenting Transactional Process Flow ....................................... 51 Introduction .......................................................................................................51 “The Product” in a Transactional World ......................................................... 52 Choosing the Level to Map .............................................................................. 52 Understand the Focus of the Value Stream..................................................... 52 Start with the Workfow ................................................................................... 53 Mapping Subtasks and Parallel Tasks .............................................................. 55 6 Showing the Flow Clearly ................................................................ 57 Introduction ...................................................................................................... 57 Providing Defnition to Subtasks and Parallel Paths ....................................... 57 Mapping the Reality of Rework ....................................................................... 58 Using Terminators to Clarify Rework in the Flow .......................................... 59 The Power of Simplicity ................................................................................... 62 7 Interpreting and Understanding Basic Product Flow...................... 65 Introduction ...................................................................................................... 65 Showing Where Flow Starts and Ends ............................................................ 65 The Traditional Mindset: Pushing Work.......................................................... 66 The Lean Concept of Pull Systems .................................................................. 66 Controlling Material When Pull Is Not Possible.............................................. 68 Calculating Customer Demand and Takt Time ............................................... 69 Showing Inventory ........................................................................................... 71 Capturing Cycle Time .......................................................................................74 Summarizing Basic Process Flow .................................................................... 76 Case Study in a Manufacturing Environment ................................................. 77 8 Utilizing Data in Manufacturing How to Add Power to Your Map with Facts ................................................79 Introduction ...................................................................................................... 79 Record the Number of Operators for Each Process ........................................ 80 Record the Cycle Time of Each Process Step ................................................. 81 Record the Changeover Time from One Process to Another ......................... 82 Record Uptime, or the Reliability of Equipment ............................................. 83 Record the Availability of Equipment .............................................................. 85 PP7359_C000.indd 8 5/29/08 9:39:20 AM Contents n ix Record Work Content and Non-Value-Added Time ........................................ 87 Record the Defect Rate .................................................................................... 87 Other Data You Might Want to Record on Your Map .................................... 89 9 Basic Process Flow in a Transactional World .................................. 91 Transactional versus Manufacturing Process Flow ......................................... 91 Difference 1: Speed of Transactional Processes.............................................. 92 Option A: Map the Process by Using the Employees’ Knowledge of the Process ....................................................................... 92 Option B: Map the Process by Working Backwards from the Last Process Step ....................................................................... 93 Option C: Use Both Options A and B ..................................................... 93 Difference 2: Transactional Employees Sometimes Do Not See a Process........................................................................................................... 93 Difference 3: Takt Time in Transactional Value Streams ................................ 94 Difference 4: Work Queues versus Piles of Inventory .................................... 95 10 Transactional Data Is Different … Or Is It? .................................... 97 Introduction ...................................................................................................... 97 Recording the Number of Employees in a Transactional Setting ................... 98 Documenting Cycle Time ................................................................................ 98 Documenting Expected (Estimated) Cycle Time .................................. 100 Documenting Changeover Time.................................................................... 100 Documenting Uptime or Reliability ...............................................................101 Documenting Availability of Equipment (AOE) .............................................102 Documenting Availability of Personnel (AOP) ...............................................103 How to Document Tasks That Supervisors and Managers Demand Be Performed Immediately ......................................................105 Documenting Defects .....................................................................................107 Capturing Other Data .....................................................................................107 Case Study in a Transactional Environment ..................................................110 11 Capturing Travel Distances throughout the Value Stream .............111 Introduction .....................................................................................................111 Measuring Travel Distance in the Value Stream ............................................111 Measuring and Documenting the Travel Path of the Product ...............112 Measuring and Documenting the Travel Path of Employees ................113 Physical Measurement of Travel ..............................................................114 Showing Travel Distance on a Value Stream Map .........................................115 Documenting Long Travel Distances within a Process Step .........................116 Check for Hidden Travel in Transactional Processes .....................................117 12 Showing the “Value” from the Process Flow ................................. 121 Introduction .....................................................................................................121 Measuring Total Cycle Time ...........................................................................122 Interpreting Parallel or Subtask Cycle Times .........................................124 PP7359_C000.indd 9 5/29/08 9:39:20 AM