Sherwin-Williams Marine Tank Lining 180°C-C

Perform DFT measurement with calibrated wet film thickness gauge (ASTM D7091): 90% of all measurements ≥ nominal DFT; maximum 10% may be between 0.9×NDFT and NDFT. Minimum 3 measurements per square meter required. Measurement only after minimum 1 week drying time.

Perform pull-off adhesion test (ASTM D4541) with portable adhesion tester: glue dolly to dry layer (≥1 week cure), increase perpendicular tensile force at constant rate until failure. Determine reading in MPa/PSI. Classify failure mode (adhesion failure at substrate, layer-to-layer failure or substrate failure). Minimum 5 test points per application area.

Measure surface profile per ASTM D4417 (Method B: depth micrometer, Method C: replica tape) BEFORE application. Determine Mean Maximum Profile (h_max) by averaging at least 20 peak-to-valley measurements. Required profile typically 50–75 µm for epoxy systems. If too shallow (<50 µm): blast clean again; if too deep (>75 µm): not acceptable.

Deploy holiday/pinhole detector: low-voltage wet brush method (≤500 µm thickness) or high-voltage spark tester (>250 µm). Move electrode surface step-by-step over all surfaces. Alarm/needle indication shows defect. Mark and document. Alternatively: UV-pigment method for large-area tank testing in darkness.

During application and cure continuously document: steel temperature (surface temperature with infrared pyrometer), relative humidity (hygrometer), dew point. Ensure steel temperature is at least 3°C above dew point (condensation risk). Air temperature between 2–43°C (Seaguard 5000 HS: 35–110°F). Document in inspection record with date/time.

Inspect visually against reference standard per ASTM D4141 Method C (gloss/color). Scan surfaces for weak points: scratches, blisters (pores), shell formation, scratches, color spots. Measure defect area with calipers and document photographically. Some surface defects (small scratches <5 mm²) are acceptable per PSPC tolerances; blisters or shell formation = rework required.