AUTOMATIC PAINT GUN WASHER

Revision: 8/96

Process Code: Navy and Marine Corps: ID-05-00; Air Force: PA01; Army: PNT

Usage List: Navy: High; Marine Corps: High; Army: High; Air Force: High

Substitute for: Manual Cleaning of Paint Guns

Applicable EPCRA Targeted Constituents: Toluene (CAS: 108-88-3), Xylenes (CAS: 1330-20-7), Methyl Ethyl Ketone (CAS: 78-93-3), Acetone (67-64-1), n-Butyl Alcohol (CAS: 71-36-3), Lead (CAS: 7439-92-1), Chromium (CAS: 7440-47-3), Zinc Compounds

Overview:

Automatic paint gun washers are similar to conventional home dishwashing machines, except that the thinners and solvents in the automatic washers are not heated in the process. The washers can be used to clean conventional air spray, HVLP, electrostatic, airless, or air-assisted paint guns. Solvents used in the automatic paint gun washer are recycled and reused in the cleaning process. The paint gun to be cleaned is attached to a nozzle within the automatic paint gun washer, and the machine is sealed. Most automatic paint gun washers can wash two to three paint guns at a time. The exterior of the paint gun is cleaned with atomized paint thinner using a dishwasher action. The interior of the paint gun is cleaned by circulating solvent through the nozzle attachment. Automatic paint gun washers collect used solvent in a reservoir. Impurities in the used solvent are filtered out in the reservoir. The filtered solvent is then ready for reuse instead of being disposed as hazardous waste. The solvent impurities form a sludge, which is collected and disposed. The typical solvent capacity of the spray gun washer is 3 gallons; it must be changed out every 3 to 8 weeks, depending on usage.

The manual cleaning of paint guns can be labor intensive and can generate significant quantities of solvent wastes. Automatic paint gun washers can reduce the amount of solvent used and paint solvent waste generated by up to 70-80% when compared to manual paint gun cleaning. Since automatic paint gun washers are sealed units, worker exposure to hazardous materials during solvent handling is also greatly reduced.

Materials Compatibility:

Chlorinated solvents can not be used in most automatic paint gun washers.

Safety and Health:

Health concerns are dependent on the variety of solvent and paint that is handled. Inhalation of lead- and zinc chromate-based paints can lead to irritation of the respiratory system. Some lead compounds are carcinogenic. Solvent-based paints can irritate the lungs and mucous membranes. Prolonged exposure can affect respiration and the central nervous system. Proper personal protection equipment (PPE) should be used.

Consult your local industrial health specialist, your local health and safety personnel, and the appropriate MSDS prior to implementing this technology.

Benefits:

  • 70 to 80 percent cost savings for solvents used to manually wash paint guns due to solvent recycling and reuse
  • Reduces the amount of hazardous waste and hazardous air emissions generated
  • Localized handling site for solvents used for paint gun washing
  • Because solvent storage is localized, procurement of standardized solvent(s) are possible for this maintenance action
  • Accurate waste solvent classification for this maintenance action is simplified
  • Fully automatic, reduces labor
  • Pneumatically operated (non-electric) washer
  • Reduces worker exposure to solvent, hazardous waste and hazardous air emissions

Disadvantage:

  • Users of automatic paint gun washers have noticed that if they delay washing the paint guns, the cleaning efficiency is reduced, and additional hand cleaning of the equipment is required.

Economic Analysis:

The capital cost for automatic paint gun washers will vary, depending upon the unit size, unit type, and the application. Capital costs for these washers range from $600 to $2,400.

Assumptions:

  • 18 spray guns are cleaned per week
  • Solvent required for automatic gun cleaning: 6 gallons/month
  • Solvent required for manual gun cleaning: 36 gallons/week
  • Hazardous waste disposal cost: $20/gallon
  • Solvent procurement cost: $4/gallon
  • Labor rate: $30/hour
  • Labor, manual gun cleaning: 10 min/gun or 3 hr/week
  • Labor, automatic gun cleaning: 1 min/gun or 0.3 hr/week
  • Electrical costs are negligible

Annual Operating Cost Comparison for
Automatic Washing and Manual Washing of Paint Guns

Automatic Wash Manual Wash
Operational Costs:
Labor: $470 $4,700
Material $290 $7,500
Waste Disposal $1,400 $37,400
Total Operational Costs: $2,160 $49,600
Total Recovered Income $0 $0
Net Annual Cost/Benefit: -$2,160 -$49,600

Economic Analysis Summary

  • Annual Savings for Automatic Washing: $47,440
  • Capital Cost for Diversion Equipment/Process: $600
  • Payback Period for Investment in Equipment/Process: Immediate

Approving Authority:

Navy: Approval is controlled locally and should be implemented only after engineering approval has been granted. Major claimant approval is not required.

Points of Contact:

Barbara Roehm (N40R)
Commander Submarine Forces, US Pacific Fleet
Pearl Harbor, HI 96860
Phone: (808) 474-9118; Fax: (808) 474-3196

Scott Mauro
Naval Facilities Engineering Service Center, Code 423
1100 23rd Avenue
Port Hueneme, CA 93043-4370
Phone: (805) 982-4889, DSN: 551-4889, Fax: (805) 982-4832

Vendors:

The following is a list of automatic paint gun washer manufacturers. This is not meant to be a complete list, as there may be other manufacturers of this type of equipment.

Technical Innovations, Inc.
2105 Austin Ave.
Troy, MI 48083
Phone: (810) 528-0232, Fax: (810) 528-9330

Butler Compressor and Spray Equipment Co.
657 Monterey Pass Road
Monterey Park, CA 91754
Phone: (818) 289-4247, Fax: (818) 284-9971

Graco Inc.
P.O. Box 1441
Minneapolis, MN 55440
Phone: (612) 623-6709, Fax: (612) 623-6777

Source(s):
Barbara Roehm, Commander Submarine Forces, US Pacific Fleet, May 1996.
Vendor Communication, Technical Innovations, Inc., April 1996.
Vendor Communication, Butler Compressor and Spray Equipment Co., April 1996.