Flanges are an integral part of any pipeline. Flanges on natural gas lines have to tolerate pressure up to 1500 psi. Of course, by the time the gas reaches its destination, the pressure is reduced to about .25 psi. Corrosion can substantially reduce durability. There are ways that you can avoid corrosion on flanges.
Unprotected flanges are at a higher risk of corrosion and failure. Periodic inspections are necessary to ensure serviceability. Destructive inspection processes can cause work stoppages and are time-consuming. A flange that is fully protected against corrosion can equate to less frequent inspections, fewer work stoppages, and less time dedicated to inspections.
Crevice Corrosion and Pitting Corrosion
The two most likely types of corrosion you will find on a flange are pitting corrosion and crevice corrosion. Pitting corrosion affects the face of the flange (the area you can see) and can result in cavities or crevices forming.
Crevice corrosion is harder to detect and therefore more dangerous. This type of corrosion is found where two flanges meet. Such corrosion often goes undetected and winds up causing widespread damage.
Anti-corrosive paint solutions can keep corrosion issues at bay. Paint solutions are simple solutions. However, they will not reduce the need for regular inspections. Additionally, you will need to have a paint maintenance schedule in place to ensure continued protection.
One of the simplest ways to prevent corrosion of flanges is to add a gasket to the setup. Gaskets can prevent corrosion by providing a barrier between the flange and corrosive chemicals. Mechanical solutions require less maintenance than chemical or paint solutions.
Start With the Right Flange for the Application
A good way of preventing corrosion is to start with the right flange for the application from the start. A high-quality flange made for the specific application is an important first step in preventing corrosion and other failures. Make sure you get your flanges from a trusted source like Lynco Flange & Fitting.