Washers are described by stage count: a three-stage typically runs a combination cleaner and iron phosphate, a rinse and a final rinse, while a five-stage separates cleaning from coating with a rinse between each. More stages mean less carry-over, better coating and better corrosion results. Seven-stage lines add a second cleaner or extra rinses for zinc phosphate or thin-film chemistries.
Our five-stage is running zirc now, so the old three-stage is just for the cheap shelving.
Also heard as
- five-stage washer
- 5-stage
Related terms
Pretreatment
The cleaning and chemical conditioning a part gets before powder, which decides most of its adhesion and corrosion life.
Wash
Line slang for the spray pretreatment washer, or for the pass a part makes through it.
Seal rinse
A final pretreatment rinse that fills pores in the conversion coating and boosts corrosion resistance.
DI rinse
Deionized water rinse, the final stage that washes salts off the part so they do not end up trapped under powder.