Second Edition Handbook for CRITICAL CLEANING Cleaning Agents and Systems Second Edition Handbook for CRITICAL CLEANING Cleaning Agents and Systems Edited by Barbara Kanegsberg Edward Kanegsberg Boca Raton London New York CRC Press is an imprint of the Taylor & Francis Group, an informa business Cover design by David Kanegsberg. CRC Press Taylor & Francis Group 6000 Broken Sound Parkway NW, Suite 300 Boca Raton, FL 33487-2742 © 2011 by Taylor and 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: 978-1-4398-2827-4 (Hardback) This book contains information obtained from authentic and highly regarded sources. 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Visit the Taylor & Francis Web site at http://www.taylorandfrancis.com and the CRC Press Web site at http://www.crcpress.com To a beautiful, safe, productive world for the next generation Noa Raeli Kanegsberg To our most valuable collaborative efforts Deborah Joan Kanegsberg and David Jule Kanegsberg And to the memory and positive influence of Israel Feinsilber Jule Kanegsberg Murray Steigman Dr. Jacob J. Berman Contents Preface to the Second Edition ..................................................................................xi Preface to the First Edition .....................................................................................xv About the Second Edition ......................................................................................xix Editors ....................................................................................................................xxv Contributors’ Bios ...............................................................................................xxvii Part I Cleaning agents 1 Cleaning Agents: Overview ..............................................................................3 Barbara Kanegsberg 2 Aqueous Cleaning Essentials ...........................................................................35 Michael Beeks and David Keller 3 Cleaning Agent Chemistry...............................................................................63 JoAnn Quitmeyer 4 Solvents and Solubility .....................................................................................95 John Burke 5 Hydrofluoroethers ..........................................................................................115 John G. Owens 6 Hydrofluorocarbons .......................................................................................131 Joan E. Bartelt and Abid Merchant 7 n-Propyl Bromide ...........................................................................................149 John Dingess, Richard Morford, and Ronald L. Shubkin 8 Vapor Degreasing with Traditional Chlorinated Solvents ............................169 Stephen P. Risotto 9 d-Limonene: A Safe and Versatile Naturally Occurring Alternative Solvent ........................................................................................................181 Ross Gustafson vii viii Contents 10 Benzotrifluorides ...........................................................................................191 P. Daniel Skelly Part II Cleaning Systems 11 Cleaning Equipment: Overview .....................................................................203 Barbara Kanegsberg 12 The Fundamental Theory and Application of Ultrasonics for Cleaning ......217 F. John Fuchs 13 Ultrasonic Cleaning Mechanism ...................................................................233 Sami B. Awad 14 Ultrasonic Cleaning with Two Frequencies ..................................................241 K.R. Gopi and Sami B. Awad 15 Megasonic Cleaning Action ...........................................................................247 Mark Beck 16 Snap, Crackle, or Pop: How Do Bubbles Sound? ...........................................259 Mark Hodnett 17 Principles and Quantitative Measurements of Cavitation ............................269 Lawrence Azar 18 Equipment Design ..........................................................................................281 Edward W. Lamm 19 From Laboratory Cleaning to Production Cleaning .....................................299 Ronald Baldwin 20 Cold and Heated Batch: Solvent Cleaning Systems .......................................315 P. Daniel Skelly 21 Flushing: A Dynamic Learning Process in Soils, Chemistry, and Equipment ......................................................................................................321 Richard Petrulio 22 Solvent Vapor Degreasing: Minimizing Waste Streams ...............................331 Joe McChesney 23 Vapor Degreaser Retrofitting ........................................................................343 Arthur Gillman 24 Enclosed Cleaning Systems ............................................................................347 Don Gray and John Durkee 25 Organic Solvent Cleaning: Solvent and Vapor Phase Equipment Overview .......................................................................................................363 Wayne L. Mouser 26 Overview to “Nonchemical” Cleaning ..........................................................373 Ed Kanegsberg Contents ix 27 Cleaning with Micro Sandblasters .................................................................381 Jawn Swan 28 Cleaning with Carbon Dioxide Snow ............................................................397 Robert Sherman 29 Cleaning with Dense-Phase CO : Liquid CO , Supercritical CO , and 2 2 2 CO Snow ........................................................................................................411 2 William M. Nelson 30 Gas Plasma: A Dry Process for Cleaning and Surface Treatment ................425 Kenneth Sautter and William Moffat 31 Superheated, High-Pressure Steam Vapor Cleaning .....................................433 Max Friedheim and Jose Gonzalez 32 Making Decisions about Water and Wastewater Processes ..........................441 John F. Russo 33 Overview of Drying: Drying after Solvent Cleaning and Fixturing ............471 Barbara Kanegsberg 34 Drying .............................................................................................................477 Daniel J. VanderPyl 35 Liquid Displacement Drying Techniques ......................................................497 Phil Dale and Robert L. Polhamus Glossary of Terms and Acronyms ...........................................................................................511 Index .......................................................................................................................515 Preface to the Second Edition Why a Second Edition? In the last few years, challenges to the manufacturing community have increased and so have performance expectations. With the ever-decreasing size of components, these expectations are becoming more difficult to meet. The second edition of the Handbook for Critical Cleaning hopes to help you meet these expectations and produce high-quality products in a cost-effective manner. Although cleaning is a process and not a chemical, increased awareness of the consequences of chemical use to workers, to the general public, and to the environment has prompted more stringent regulatory measures worldwide. Environmental and worker safety regulations are imperative to maintaining a decent quality of life on this planet and, perhaps, to our very survival. However, the goal of manufacturing is not to jump through regulatory hoops, but to produce efficient products. Compromising on the efficacy of cleaning and thereby producing a suboptimal product can affect public safety and can compromise on the quality of life. Manufacturers face the challenge of doing it all. What Is Critical Cleaning? Identify, then qualify/validate and monitor the critical cleaning steps. The terms “critical cleaning” and “precision cleaning” are often used interchangeably. However, we prefer the former term. Precision cleaning suggests cleaning in a highly restricted clean room, where each individual component is perhaps cleaned separately by a highly trained technician, where there are perhaps wet benches with automated product handling, and where there may be a multichamber-automated spray system that feeds directly into the clean room. This is a limited view of the important cleaning step. Perhaps the best way to define a critical cleaning step is to consider the negative consequences that arise if that step is not performed or is performed inadequately. Based on our experience, the important cleaning step, the critical cleaning step, may occur in a machine shop or in a job shop (e.g., a coating facility) in what appears, at first glance, like an automotive repair facility. If the soil (matter out of place) is not adequately removed at that step, subsequent processing and cleaning steps may not resolve the problem but may actually exacerbate contamination by inadvertent chemical reaction of the soil, dry- ing of the soil, or by embedding the soil on the surface of the product. Contamination happens long before the product enters the clean room. A clean room can only minimize recontamination, and even the most sophisticated clean room or controlled environment cannot correct a contaminated product (Kanegsberg and Kanegsberg, 2010). xi xii Preface to the Second Edition Lean Cleaning and Supply Chains Economic pressures have led to the implementation of such concepts as lean cleaning and six-sigma; thus, we have to clean smarter. In fact, it is imperative that we clean smarter. Cleaning must be value added. Assess your own processes and understand the role that cleaning plays in those processes. Sometimes the value added is only appreciated by factoring in the costs of not cleaning or under- cleaning at a particular step. Critical cleaning is not just about what is done or how it is done. It is also about when it is done. This becomes even more important when we realize that most products are not built from scratch within one facility. There usually is a complex supply chain of autonomous or semiautonomous facilities, which may sometimes be separate divisions or departments of the same company. Regardless of whether the supply chain involves inter- or intracompany processes, it is cru- cial that communication take place and that process understanding and process integration occur. The most critical cleaning step may be one that needs to take place at a supplier, before the part reaches your facility. Critical Cleaning and Surfaces Cleaning is removing undesired materials from surfaces without changing the surface in an unaccept- able manner. As products get smaller, the surface becomes a greater percentage of the product. When products are at the nanoscale, it can be said that the product is the surface. New and Useful Cleaning Is a Process The economic and regulatory hurdles involved in introducing new cleaning agents have increased considerably (see “A balancing act” in book 2). Therefore, chemicals that have been developed for markets other than cleaning but have been adapted for the cleaning sector and complex blends have become increasingly prevalent. Therefore, the newer cleaning products are covered extensively in the second edition. Cleaning equipment has also evolved during the past decade, and meshing the appropriate cleaning agent with the right equipment requires a working understanding of chemis- try, physics, and engineering. We have added discussion of ultrasonic techniques and monitoring. Partially spurred by regulatory pressures, an increased use of so-called nonchemical approaches is included. Process Implementation All of the knowledge in the world about cleaning agents, cleaning equipment, and process flow is of no use if you do not improve the cleaning process. We provide guidance to actually do something: to select, validate, implement, and monitor the cleaning process. We also cover new approaches to defini- tive, lean, analytical testing and provide discussions related to clean rooms, including construction and working in a clean room. applications The application portion of the Handbook for Critical Cleaning has been expanded to include critical cleaning processes for high-value products such as for medical devices, pharmaceutical, food process- ing, aerospace, and military. Electronics cleaning, which had been considered to be “solved” a decade ago, has resurfaced as a critical issue due to such developments as miniaturization, increased component Preface to the Second Edition xiii density, and replacement of lead solders with lead-free, higher temperature solders. Conservation of fine art may not immediately be thought of along with manufacturing, but this involves critical cleaning and the requirements are in some ways similar. Two art conservators outline the thought processes and trial- and-error determinations to match cleaning agents to the soil when cleaning or restoring paintings. Safety/Environmental Considerations Safety and environmental considerations are not only global issues but are also important concerns at the national and local levels, and they do not always coordinate or mesh well. You cannot ignore them, and you should not ignore them. We have not attempted to outline all regulations. Dealing with such a moving target would be frustrating and futile, and most engineers would develop glazed eyeballs. Instead, we have attempted to discuss a few topics that are important to the critical cleaning community and to provide strategies for working constructively with the regulatory world. Some of this guidance comes from members of the regulatory community. Resource conservation is becoming an important topic in the twenty-first century. Efforts to minimize or recycle water, chemicals, and energy will increasingly become a factor in keeping pro- cess costs competitive. Green cleaning, which considers both safety and environmental impact, is discussed throughout the two books. The definition of green is not set in stone; it will continue to evolve. Web-Based Material Some of the authors have submitted non-print media (color illustrations, animations, film clips, etc.) to augment their chapters. These can be accessed via the “Downloads & Updates” tab on the web pages for these books at CRCPress.com. the Lady in the Saffron Sari Barbara Kanegsberg “You must run, you must flee,” implored the earnest gentleman as he ran toward us. Puzzled and slightly alarmed, our daughter Deborah and I peered down a corridor of immense, mul- ticolored marble slabs while balancing a finished wood cabinet door, a celadon green tile, and some decorative hardware. It was a brilliant, Southern California morning. The silhouette of the plaster Disneyland Matterhorn broke through a cloudless blue sky. The only obvious danger was the trauma of remodeling the kitchen. “Why do we need to run?” I asked. “You must hide, my wife must not see you,” he replied. “Why can’t your wife see us?” our daughter asked. “Because, you see, I told her, first we will select the marble, then the cabinets, then the tile, then the door pulls. You are coordinating. If she sees you, she will want to coordinate.” At that very moment, an elegant woman wearing a luminous, saffron-yellow sari came gliding across the marble yard. “You see, dear,” she said, putting her arm around the gentleman and steering him purposefully toward the exit, “they are coordinating. Let’s go, we must coordinate too.”