In any type of application where metal is exposed to moisture, there is the risk of corrosion damage. For plumbing systems, utility companies, water and sewer systems, or any of type of similar application, protecting metal pipes from corrosion is a priority.
There are several different options in cathodic protection. Some of the more costly involve fully encasing a pipe in a non-corrosive material, but this is often impossible in smaller systems where the risk of a toxic spill is not a major concern or factor.
For these types of systems, and also for oil and gas pipelines, different options in cathodic protection can provide a cost-effective solution. The use of this type of protection is highly effective and can be used in any type of environment or application.
How it Works
The goal of cathodic protection methods is to divert the corrosion to an alternative location, protecting the metal in the pipe from the damage.
All ferrous metal corrodes, to some degree, in the presence of water, and specific minerals found in the soil. Sulfur is particularly problematic, but so is the presence of chloride salts. Even factors such as the organic material in the soil can lead to increased rates of corrosion. With some types of cathodic protection, a sacrificial metal is used to attract the reactive elements and to protect the metal in the pipe.
Other systems may use coatings to protect the pipe. These coatings are applied to the exterior of the pipe. The products are designed to adhere completely to the surface of the pipe to prevent the coating from separating from the metal (cathodic disbondment) and creating a space where oxidation can occur.
These coatings can be sprayed on, painted on, or applied through a process that covers the entire pipe with the coating. Tape and mastic can also be used to cover joints, elbows, and fittings in the pipe.
