In the coating industry, how is a lining defined?

A lining is defined as a coating applied specifically to surfaces that will be immersed in liquids, often for the purpose of providing corrosion resistance, chemical resistance, or physical protection. This type of coating is vital for applications such as tanks, pipes, and containers that are frequently in contact with liquids. Typically, linings form a barrier between the surface they are protecting and the potentially harmful substances, thus extending the life of the underlying substrate and ensuring safety and functionality.

The focus on immersion surfaces highlights the unique challenges and requirements of these coatings, such as the ability to withstand prolonged exposure to corrosive environments. Other options do not encompass the specific characteristics and applications that define linings. For instance, while external coatings serve a different purpose, and temporary protective coatings or surface treatments target different needs altogether, linings are distinctly formulated and intended for immersion scenarios. This ensures they meet the precise demands of service conditions faced in such environments.