MIST COLLECTION OF METALWORKING FLUIDS HOW TO CONTROL, CONTAIN, AND FILTER COOLANT & OIL MIST A TECHNICAL REFERENCE GUIDE TABLE OF CONTENTS WHY Mist Collection? ................................................................................. 4 Start with the Basics .................................................................................. 4 What is Mist? .....................................................................................................................4 What is Smoke? ................................................................................................................4 History of Mist Collection .................................................................................................5 Steps to Selecting the Right Mist Collector ....................................................................6 1. Determine Your Needs ........................................................................... 6 1A. Types of Machines Generating Mist ....................................................................6 Metal Cutting Operations – Mills .........................................................................6 Metal Cutting Operations – Turning ....................................................................7 Metal Grinding Operations ...................................................................................7 Metal Forming Operations – Heading and Stamping ........................................8 Metal Forming Operations – Casting ...................................................................8 Drawing Operations ..............................................................................................9 Heat Treating .........................................................................................................9 Part Washers ..........................................................................................................9 Electrical Discharge Machine (EDM) Operations ..............................................10 Lube Oil Reservoirs .............................................................................................10 Plastic and Rubber Applications ........................................................................11 1B. Types of Lubricants and Coolants......................................................................11 Water-Soluble (Water-Soluble, Semi-Synthetic, Synthetic) Coolants ............11 Straight Oil ...........................................................................................................12 Properties of Coolants and Lubricants ..............................................................13 1C. The Purpose of a Mist Collector .........................................................................14 1D. Determining Airflow............................................................................................14 Open Area Method for Enclosed Machines ......................................................14 Air Exchange Method for Enclosed Machines ..................................................15 Machines without Good Enclosures ..................................................................15 Handling Hot Airflow Applications ....................................................................16 1E. Selecting a Mist Collector Based on Calculated Airflow ..................................17 1F. Location of Mist Generated.................................................................................17 Frequently Moved Machining Centers ..............................................................18 Infrequently Moved Machining Centers ............................................................18 1G. Combining Mists .................................................................................................18 2. Types of Collector Installations ........................................................... 19 2A. Machine-Mounted Systems ...............................................................................19 2B. Ducted Single Machining Center Systems ........................................................19 2C. Ducted Cellular Systems .....................................................................................20 2D. Ducted Central Mist Systems .............................................................................20 2E. Ambient Mist Filtration Systems ........................................................................20 3. Installing the Mist Collector ................................................................ 22 3A. Locating the Mist Collector – Indoors vs. Outdoors .........................................22 3B. Hooding Designs .................................................................................................23 3C. Machining Center Pick-Up Point Location .........................................................24 3D. Ducting Types ......................................................................................................24 3E. Ducting Do’s and Don’ts .....................................................................................26 3F. Electrical Controls ................................................................................................27 3G. Drains ...................................................................................................................27 P-Trap ...................................................................................................................27 Drain Hose with Loop .........................................................................................28 Drain Hose without Loop ....................................................................................28 Drain Collection Container .................................................................................28 3H. Gaskets and Caulking ...................................................................................29 4. Selecting the Right Mist Filter Media & Collector Configuration ........ 29 4A. Filter Media Technology .....................................................................................29 4B. HEPA / 95% DOP Filter Media Technology .......................................................31 4C. Mist Collector Technology ..................................................................................31 Centrifugal Mist Collector ...................................................................................31 Electrostatic Precipitators ...................................................................................32 Mist Collectors with Panel Filters .......................................................................33 Media/Vee-Bag Mist Collector ............................................................................33 Cartridge Mist Collector ......................................................................................34 5. System Operation ............................................................................. 34 5A. Start-Up Procedures............................................................................................35 5B. Balancing the Airflow .........................................................................................35 6. Troubleshooting Common Problems .................................................... 36 7. Glossary ................................................................................................ 39 COOLANT & OIL MIST TECHNICAL REFERENCE GUIDE WHY MIST COLLECTION? START WITH THE BASICS For over 50 years, manufacturers of metal products What is Mist? have been purchasing and installing mist collectors Mist is commonly thought of as a small liquid on their mills, drills, lathes, grinding, casting, and droplet, but in different industries, the definition is other metal cutting, metal forming, and related more refined. For this guide, mist is defined as: machines to: • A liquid particle 20 microns or smaller. • Provide clean air for their workers, This manual focuses primarily on applications reducing the adverse affects of exposure that use oil and water-soluble lubricants, coolants, to metalworking fluids and mist. and detergents that during use generate a mist • Comply with local, state, and federal and require the control of a mist collector. These indoor air quality standards. applications include, but are not limited to: • Minimize accidents and maximize • metal cutting worker effectiveness. • metal forming • Reduce maintenance costs. • metal grinding • Improve quality. • part washers In selecting the mist collector, the purchasing manager often must rely on sales presentations from • lube oil systems mist collector manufacturers. Perhaps they browse What is Smoke? through brochures and test reports showing that Smoke is commonly thought of as that gray to each product available is best for their situation. Not black cloud emitted from burning wood, out of the an ideal way to ensure that what is purchased is the smoke stack on a semi truck, what you see and right solution. smell when someone is smoking a cigarette, and This manual has been put together to address what is produced when you weld two pieces of steel common questions involved in purchasing a mist together. This is not the type of smoke that we are collector, such as: referring to: • Which filtration technology is the best? In this guide, smoke is defined as: • Individual machine-mountable units or large • A liquid particle that condenses from a vapor central systems? to a liquid, typically 0.07 to1 micron in size. • Ambient