A new pre-weld immersion cleaning and etching line from PSI has been developed to accommodate the demand for larger propellant tanks. Each of the cleaning vats has a volume of 5.5 ft3. In the first stage of the cleaning process, all components are washed for about 15 minutes in a concentrated alkaline bath, then dipped in a distilled water rinse. Surface contamination of hemispherical components is then removed by immersing them in a solution comprising 30 percent nitric acid and 3 percent hydrofluoric acid. In the case of more delicate components, a 35 percent nitric acid bath is used to remove surface contaminants. A rinse in tap water and then in hot DI water completes the cleaning process.
Pressure Systems Inc.
Los Angeles, CA