Method B: Visible Penetrant Post-Emulsifiable (Lithophilic)
Guide to Method B (lipophilic) processing per ASTM E-1417.
1. Pre Clean The Surface
Use Met-L-Chek® E-59A, R-503 or R-504 to remove oil, grease and other contaminants from the test surface. Part must be clean, dry, and at a temperature of 40-125°F (4.4-52°C) before penetrant is applied.
Products to Use:
2. Apply Penetrant
Apply Met-L-Chek® VP-31A onto a clean and dry test surface using spray, immersion or wipe on. Wait a minimum of 10 minutes; 20 minutes if temperature is between 40-50°F (4.4-10°C) before proceeding to the next step.
Products to Use:
3. Apply Emulsifier
Apply Met-L-Chek® E-50 emulsifier by spray or flow on. Use a drain time of under 2 minutes.
Products to Use:
4. Wash
Wash the part.
- Water Temperature: 50-100°F (10-38°C).
- Water pressure: < 40 psi (< 275 kPa).
- Wash Distance: > 12 inches (> 30 cm).
For Water-Based Developers go to step 4.A
For Non Water-Based Developers skip to step 4.B
4.A Water Based Developers
Apply Met-L-Chek® D-78B developer using immersion or spray prior to drying.
Products to Use:
4.B Non-Water Based Developers
Dry the part to be inspected and then apply Met-L-Chek® D-70.
Products to Use:
D-70:
5. Inspect
Wait a minimum of 10 minutes before inspection.
- Maximum time is 1 hour for form “f” (non-aqueous) developers.
- Maximum time is 2 hours for form “c” (aqueous) developers.
If times are exceeded, clean part and reprocess. Use illumination of > 100 foot candles (>1100 lux/m2) to inspect.