The first and perhaps the most critical step in obtaining a quality finish is the effective pre-treatment (e.g. washing) of the product surface.
The majority of industrial coatings require the thorough cleaning of all dirt, oils, and contaminants from the product surface and treating the product surface with phosphate or conversion coatings to prevent corrosion and increase paint adhesion.
The quality of the surface preparation process and equipment sets the standard for all subsequent operations in a finishing system. KOCH skilled engineers will ensure that your surface preparation machine is properly designed as a good beginning to your total coating process.
Washers may be fabricated from mild steel, stainless steel, or fiberglass reinforced plastic (FRP) material.
The operating efficiency of a washer is a major factor in its design. Energy saving features such as FRP construction, bottom entry/bottom exit, vestibule air seals, water reuse, design and selection of nozzles, tank and housing insulation, and the reuse of exhaust heat from gas-fired burners are some of the considerations KOCH engineers will evaluate for energy conservation in your equipment.
Power spray washers are the most popular method of performing surface preparation. These machines, usually conveyorized, are readily adaptable to many applications and are preferred for high production lines.
These units employ acid or alkaline cleaners, followed by water rinses, conversion coatings, and sealers. Deionized or R/O water may be used as a final rinse to minimize any contaminants on the substrate.
Power spray washers usually have from two to seven stages, but may have more depending on the desired quality of the final finish. Three and four stage spray washers combine the cleaning and conversion steps. When heavier soils are to be removed or higher quality coatings desired, five to ten stage washers are generally used. These provide for multiple cleaning and rinse stages in addition to a conversion coating stage, a sealer stage and a deionized or R/O water rinse.
Drain zones must be properly engineered to minimize carryover and contamination, yet limited so that flash rusting does not occur between stages.
Provisions for removing dirt and sludge with minimum maintenance and labor are also important considerations that KOCH engineers will explore with you.
Spray -Dip Combination
A variation to the spray washer is the combination power spray and immersion arrangement. The spray and dip combination may be required with complex parts that do not lend themselves to good cleaning by spray only.
Wastewater treatment is an integral component of the surface preparation machine. The surface preparation process produces wastewater that is contaminated with a variety of chemicals. Some of these chemicals may be toxic, and their discharge regulated. A wastewater treatment system neutralizes, precipitates and filters out contaminants through a series of precisely controlled processes. KOCH engineers can design your machine to conserve water usage and minimize waste treatment requirements.
Mild Steel Washer
Stainless Steel Washer