Industrial Plant Engineering Practice Test

Crevice corrosion happens when a small, tucked-away space at a joint—such as between flange faces, the gasket, and bolts—forms a stagnant micro-environment where chemistry changes promote metal dissolution. The best way to prevent this is to minimize or eliminate those crevices through proper gasket selection and tight, uniform clamping. Choosing a gasket material that is chemically compatible with the fluid and operating conditions reduces the chance of reaction at the interface and lowers the likelihood of a protected, stagnant area forming. Proper clamping ensures even compression across the gasket, seals any irregularities, and prevents gaps or looseness that would trap fluid. When the joint is well-sealed and the gasket is appropriately chosen and installed, there’s less opportunity for stagnant, corrosive pockets to develop.

Coatings might help on exposed surfaces, but they don’t reliably address the tiny gaps and crevices at joints, and coatings can be damaged during assembly. Magnets don’t influence crevice corrosion, and simply increasing pipe diameter doesn’t tackle the chemical and micro-geometry issues at joints that drive crevice corrosion.