Troubleshooting guide to iron phosphatizing
Problem, Cause and Remedy
|Poor Coating||pH not in range. |
See “Poor Cleaning.”
|Adjust pH down with acid,
up with caustic.
|Poor Cleaning||Temperatures too low||Raise temperature|
|Concentration too low||Increase concentration|
|Poor exposure to cleaner||Check racking.
|Spotty Coating/ Streaking||Contaminated rinses|
|Check rinse tanks.
|Contaminated rinses||Check rinse tanks|
|Poor exposure||Check racking.
|Rusting||Coating weight too low||Raise temperatures.
|Dry-off too slow||Increase temperature in final rinse.|
|Drying between stages||Run at lower temps.
Better placement of nozzles.
Use fog nozzles
|Solutions Foaming||Temperature too low||Raise temperature|
|Pressure too high||Check for plugged nozzles|
|Pump picking up air||Check pump packing.
Check water level.
|Poor Paint Adhesion||Coating too heavy||Lower temperature.
|Poor cleaning||See “Poor Cleaning.”|
|Contamination||Look for source of silicone near washer.|
|Bad steel||Check raw material for excessive soil.|