SIGMA Z-COAT: THE Corrosion Protection Plan

SIGMA Z-COAT provides unparalleled galvanic protection to ductile iron in corrosive environments. In the SIGMA Z-COAT process, the zinc coating is applied by spraying zinc-rich paint onto the surface. It complies with ISO 8179-2 specs.

The zinc-rich paint, or SIGMA Z-COAT method, is considered superior for use on fittings and other products with rough surfaces and non-uniform shapes. Because it is applied as a liquid, SIGMA Z-COAT permeates all surfaces and fills the peaks and valleys formed in the fitting manufacturing process. This prevents voids in coverage, which can result in corrosion and ultimately, failure.

The benefits of SIGMA Z-COAT include:

  • Galvanic protection to ductile iron for corrosive soils or wastewater immersion.
  • Advanced coating protection with highly effective galvanic protection properties, tenacious bonding, and abrasion resistance.
  • Adherence to ISO-8179-2 requirement for liquid inorganic zinc-rich coating.
  • Paint dry film minimum zinc content not less than 235 g/m2. Heavier coating of 300 g/mcan be applied. 
  • Minimum coating thickness of 3.5 mils.
  • Asphaltic topcoat paint applied as per ISO 8179-2.
  • Light spray gun reduces worker fatigue, improves control, and results in even coating.
  • Safer for workers as it is non-vaporized; minimal risk of inhaled aerosols, requires less PPE.

Even though SIGMA Z-COAT is a superior coating for fittings, ARC ZINC, which conforms with ISO 8179-1 and is applied by Arc spray, is available upon request.

For information about SIGMA ZINC Fittings, please contact Stuart Box at or Dennis Wilson at