Cratering refers to crater-like depressions on an electrodeposition film.
Q1:
Substrate degreasing failure (remaining oil)
A1:
- Enhance degreasing and rinsing processes.
In the case of cratering in the interior, be careful about degreasing failure.
Q2:
Oil or other contamination of electrodeposition paint.
A2:
- Remove oil with an oil magnetic filter.
- Raise the ash content to mitigate damage caused by cratering.
- Be careful about the oil or other contamination and continued or sporadic entry of contaminants accompanying the substrate.
Q3:
Oil remaining at sheet steel joints.
A3:
- Enhance the degreasing process.
- Ensure that the baking temperature increases gradually.
Q4:
Oil blown out from devices.
A4:
- Oil may be blown out in conjunction with the air from the air blower.
(Oil deposits occurring after electrodeposition can also cause cratering.)
Q5:
Cratering due to conveyor oil in the baking and drying oven. (Oily dust, iron particles, etc.)
A5:
- Conduct cleaning regularly to ensure that nothing falls.
Q6:
Contamination by oil used for equipment construction/installation in areas nearby. (Specifically, sprayed lubricant mist)
A6:
- Prevent thoroughly the entry of oil into the coating process.
Even a trace amount of oil mist can affect the coating.
Q7:
Spray dust from intermediate/top coating.
A7:
- Prevent thoroughly the entry of spray dust.