Amazinc Paste

The touch-up and repair of hot-dip galvanized steel coatings is important to maintain uniform barrier and cathodic protection as well as ensure longevity. Although the hot-dip galvanized coating is very resistant to damage, small voids or defects in the coating can occur during the galvanizing process or due to improper handling of the steel after galvanizing.

Touch-up and repair of galvanized steel is simple whether newly galvanized or in service for years. But there are more restrictions to the allowable repairs on a new product than one that has been in service.

ASTM A780

The main restriction in the specification for repairing newly galvanized material is the size of the area which is outlined in the product galvanizing specifications (A123, A153, and A767). According to those specifications, the allowable surface area for repair is no more than ½ of 1% of the accessible surface area on that article, or 36 in² (22,500 mm²) per ton of piece-weight, whichever is less. ASTM A780 Practice for Repair of Damaged and Uncoated Areas of Hot-Dip Galvanized Coatings contains details how to repair the damaged coating.

at least 2.0 mils (50.8 µm)

Another tenet of the specification for touch-up and repair is the coating thickness of the repair area. Touch-up materials are required to meet a coating thickness of at least 2.0 mils (50.8 µm) for one application, and the final coating thickness of the repair area is dictated by the material used to do the repair, outlined below.

Zinc-Rich Paints

Zinc-rich paint is applied to a clean, dry steel surface by either a brush or spray. The paint must contain either between 65% to 69% metallic zinc by weight or greater than 92% metallic zinc by weight in the dry film. Paints containing zinc dust are classified as organic or inorganic, depending on the binder they contain. Inorganic binders are particularly suitable for paints applied in touch-up applications of undamaged hot-dip galvanized areas.

The coating thickness for the paint must be 50% more than the surrounding coating thickness, but not greater than 4.0 mils (100 µm), and measurements should be taken with either a magnetic, electromagnetic, or eddy current gauge to ensure compliance.

Features

• Provides long-term protection against rust and corrosion
• High-purity, heat & weather resistant zinc protection
• Performs touch-up on galvanized parts
• Used for protection after welding and assembly works
• Prevents oxidation for a long time
• Dries fast, heat resistant (120°C)

Areas of Use

• Zinc Paste is used mainly for aesthetic purposes as it gives a bright appearance of aluminium. It also has a good chemical and abrasion resistance, enabling its use in industrial environments.
• Used for coating, priming and touch-up on bodywork components. Used on agricultural machinery, trailers, vehicles and tow cars, silos, greenhouses, construction machinery, steel structures etc.

Application

• Can be applied on a clean surface with a brush, paint roller, traditional industrial air brushing or the airless method.
• Corners, sharp contours, bolts and nuts have to go pre-treatment prior to application; paste is applied uniformly in one layer with a brush afterwards.

Technical Data

Appearance: Liquid
Colour: Gray
Odour: Characteristic
Art. Nr.: W 140 620
Package: 1 kg