Steelseal Repainting System for Peeling/Flaking (unsound) PVC Plastisol/HP200/HPS200

Standard Specification No. 6

PREPARATION
Remove all existing coatings back to the galvanised substrate by the most suitable means. Trials may be carried out to ensure the most practical method is used. Typical methods include:

1. Proprietary Chemical Stripper
Use in accordance with the manufacturer’s recommendations. After allowing the stripper to react, remove coating by scraping and/or pressure washing. Repeated application may be necessary for complete removal of Unsound Plastisol.

Thoroughly wash down using a suitable detergent solution to remove all stripper residues, dirt, grease and other deleterious matter. This should be supplemented with scrubbing brushes/nylon scouring pads etc. to remove stubborn residues. Rinse with clean water and allow to dry.

Remove corrosion by mechanical abrasive tools to achieve bright metal substrate. Most common areas of corrosion occur at sheet ends/sides, overlaps and as a result of mechanical damage. Any white zinc salts must also be removed by dry abrading using nylon scouring pads or similar.

2. Abrasive Blast Cleaning
Wet or dry blast clean in accordance with equipment manufacturer’s recommendations. Remove all Unsound Plastisol and prepare corroded areas to bright metal (Sa 2.5 grade ISO 8501-1:88). Remove all blasting debris. Apply primer as soon as possible to avoid deterioration of blast standard.

3. High Pressure Water Equipment
Use in accordance with the manufacturer’s instructions.

Remove corrosion by mechanical abrasive tools to achieve bright metal substrate. Most common areas of corrosion occur at sheet ends/sides, overlaps and as a result of mechanical damage. Any white zinc salts must also be removed by dry abrading using nylon scouring pads or similar.

Preparation of the substrate may also be carried out using a combination of the above methods.

Control water/blast pressures and techniques so as to avoid 1) damage to sheets, 2) minimise removal of any sound galvanise and 3) prevent excessive ingress of water/blast media under sheet overlaps. Where ingress occurs thoroughly dry and remove any blast media.

Ensure all surfaces are clean, dry and free from oil, grease or other deleterious matter before painting commences.

PAINTING

Patch Primer:
To bare prepared steel areas apply: Steelseal Primer, PC4VC Series, (Brush & Airless Spray Qlty), DFT 50-60mms. This patch coat should be applied as an overall coat in the case of abrasive blast cleaning as this method of preparation often depletes the protective galvanise layer.

Apply Overall

1st Coat: Steelseal Primer, PC4VC Series, (Brush & Airless Spray Qlty), DFT 50-60mms.

2nd Coat: Steelseal Topcoat, PC5VF Series, DFT 50-60mms

*3rd Coat: Steelseal Topcoat, PC5VF Series, DFT 50-60 mms

* The second application of the topcoat will depend on the method of application, surface profile detail and the colour choice

Consideration should be given to surface profile, accessibility, location and equipment used. Work should be carried out using good painting practices and application techniques to ensure that a continuous, even wet film is applied. Pigment orientation of metallic shades can result in sueding effects if applied incorrectly.

The above suggestions are given in good faith, without prejudice or liability, and all materials should be applied in strict accordance with the product data sheets and Steelseal repaint Systems - Notes for guidance.

This specification is valid for 6 months from the date of the document. Further deterioration in site conditions may occur after this time, which would require a new specification. All materials are subject to Akzo Nobel Industrial Coatings Ltd Current Terms and Conditions of Sale.