SIGMA Offers Large Zinc Anode Caps, Sizes ¾” and 5/8”

Zinc Anode Caps offer cathodic protection to underground and submerged threads, bolts, and nuts on glands, flanges, and mechanical fittings. They are designed to be used in water treatment plants, weirs, lock gates, and any other structures with exposed metal threads.

How Zinc Caps Work

Corrosion is an electrochemical process in which dissimilar metal parts form a galvanic cell when they are in contact with moisture. Using the common battery as an example, moisture becomes the electrolyte while the different metals in the system (such as bolts, nuts, fittings etc.) become the positive and negative ends of the battery. The more “negative” component loses material thru corrosion while protecting the “positive” component, which becomes shielded. Because zinc is much more negative than most other materials, the protected component is essentially immune to corrosion as long as there is Zinc remaining to consume. Zinc Anode Caps offer protection for other system components made of steel, cast iron, ductile iron, brass and copper. The quantity of Zinc Anode Caps used determines the service life of the protected component. Zinc Anode Caps are made from Special High Grade Zinc that conforms to the highest industry standards that meet or exceed all MIL-A-18001J and ASTM B418-80 specifications. Zinc Caps should be installed on all exposed bolts of pipeline fittings depending on soil conditions.

These anodes are suitable for:

  • Pipeline installers and manufacturers
  • Pipeline flange manufacturers and suppliers
  • Dredging companies
  • Submersible pump manufacturers and suppliers
  • Water boards and Utility providers
  • Councils, water and sewerage departments
  • Corrosion engineering
  • Wharf and jetty construction companies

For information on these and other SIGMA products, please contact your regional office