Fitting corrosion protection is a lot easier to manage with a process known as metallized arc spray of zinc. SIP’s ARC-ZINC thermal zinc application process gives the industry the maximum corrosion protection available with over 300 g/m² coverage. Zinc is an extremely effective undercoat due to its excellent adhesive properties and enhances the corrosion resistance of the coated surfaces. Zinc coating is basically an anode, uniformly adhered to the surface of the pipe acting as a ‘patina’ or metallic barrier that keeps further corrosion from reaching the surface of the coated object. The more Zinc the better the protection is the slogan. Ductile Iron manufacturers around the world have been using this process since 1950’s with great success.
Many municipalities have specified this for new pipe installations, but fittings have been left out in the dark. Why not protect the fittings just like the pipes are protected? This is a question the Engineers at SIP looked and then studied what was out there. As we researched it became more evident that “more Zinc the better the protection”.
Below is a quick comparison guide between ARC-ZINC and ZINC Rich Paint:
|ARC-ZINC||Zinc Rich Paint|
|ISO 8170-01 Standard||ISO 8170-02 Standard|
|99.99% pure Zinc||85% pure Zinc applied at 2 to 3.5 mils max|
|Coverage of 300 g/m² to 400 g/m²||Coverage of 130 g/m² to 235 g/m²|
|Overspray not a factor||Over and Under spray has detrimental affect|
|Physical inspection of thickness and uniformity||Settling of Zinc in paint can cause uneven coating no verification|
|No Mud Cracking||Will Mud Crack at 6 Mills, detrimental affect|
|Pot Life Not Applicable||Must be constantly agitated and limited Pot life|
|Applied and cured regardless of Weather/Humidity||Curing and application Weather/Humidity dependent|
|Seal coat creates an oxide layer||Seal coat can cause Mud Cracking, detrimental affect|
|Any topcoat can be applied||Topcoats need be approved by Zinc Rich Paint Manufacturer|
|Greater surface adhesion (Nickel Scratch Test)||Lower surface adhesion (Nickel Scratch Test)|
|Matches Pipe Manufactures||Different than the adjacent pipe Zinc Process|