Power Washers
Case Studies
Crown Equipment Corporation, New Bremen, OH, manufactures electric lift trucks and television antennae
rotors. Mild steel, aluminum, cast iron, and copper are all used and cleaned at the plant. In 1988 Crown used
208,000 lb. of TCA in cold cleaning (dipping) and vapor degreasing operations. Hand dipping now uses a
water-based cleaner with rust inhibitor added for corrosion resistance. 100% d-limonene spray cleaner has
replaced TCA for hand wiped parts. An alkaline aqueous immersion cleaner has replaced one degreaser (with
inhibitor added for ferrous parts). The other degreaser was replaced with an aqueous power washer which uses
heat, agitation, and forced air drying to produce clean parts. The payback period for the capital expenses was 10
months. In 1989 Crown saved $100,000 in chemical costs. Crown Equipment has switched to water -based
cleaning with no decrease in production. Employees prefer the water-based cleaner for hand dipping.
Kohler, Kurt, and Anthony Sasson, Case Studies: Multi-Industry Success Stories to Reduce TCA use in Ohio,
Pollution Prevention Review, Autumn 1993, pp. 407-409.
The Marine Corps Air Station Naval Aviation Depot, Cherry Point, NC, is responsible for the complete
maintenance/rebuilding of naval aircraft. In 1990 the depot used 8000 gallons of CFC-113 and 15,600 gallons of
1,1,1-trichloroethane. By the end of 1992 CFC-113 usage had been reduced to 500 gallons annually and TCA
usage had been cut to about 4800 gallons annually. The replacements included: soap bubbles for leak checks;
aqueous power washers for electronics, motor, and engine shop use; terpene cleaners for hand wiping; steam
cleaning or wet sodium bicarbonate blasting for soil and carbon removal; and plastic media blasting for paint
removal.
Fennell, Mary Beth and Roberts, James Mark/Naval Aviation Depot, Hazardous Minimization-Saving Time,
Money , and the Environment, proceeding of the Aerospace Symposium, January 1993, Lake Buena Vista,
Florida, pp 39-46.
Modern Windows and Awning Company (MOCO) uses a six stage power washer to clean metal storm and screen
doors prior to powdercoating. The power has alkaline aqueous wash, followed by water rinse. The final rinse
contains a corrosion inhibitor. Cleaning is followed by oven drying and powder coating. The powder coating
process yields a high quality finish on the windows and doors and has very little waste. The dry powder overspray
is collected and reused. Fixtures used in the spray booth collect very little of the powder and are cleaned
occasionally by burning off the paint buildup. The entire cleaning/finishing process uses no ozone depleting
solvents.
For Aluminum Window/Door Fabricator: Powder Coating is Finish of Choice, Plating and Surface Finishing,
July 1993, v80, n7, pp 8-9.
A steel mill had been cleaning 42 inch roller bearings by boiling them in fuel oil for 6-8 hours in a 300 gallon vat.
This was followed by manually scraping and brushing to remove the high temperature grease used in the bearing.
They installed a spray washer (80 gpm, 75 psi, 160 F) as an alternative. The spray washer cleans the bearing in
15 minutes and gets it cleaner than the old method. The cost of the spray washer was returned to the company in
6 months in labor savings alone. As a result of installing the new washer they are cleaning the bearings more
often (prolonging bearing life), and have eliminated a significant safety hazard.
Nourie, Steven M./American Metal Wash, Inc., Aqueous Clean Does Work, Proceedings of the 1991 International
CFC and Halon Alternatives Conference, Baltimore, MD, pp 61-62.
The company assembling the Maverick missile first has to clean and paint the housing. Previously the housing
was solvent cleaned by hand followed by a four coat wet (solvent) paint system. This was replaced by an aqueous
wash with a biodegradable detergent, rinse and dry. After cleaning the missile housing was powder coated with
paint and cured. The company is achieving a better quality finish on the housing for less money. The aqueous
wash gets the surface of the housing clean enough so that powder coating is an option. The new system uses no
solvent and emits no VOC's.
Nourie, Steven M./American Metal Wash, Inc., Aqueous Clean Does Work, Proceedings of the 1991 International
CFC and Halon Alternatives Conference, Baltimore, MD, pp 63-64.
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