What should existing slip on flanges be checked for during inspection?

During the inspection of existing slip-on flanges, it is particularly important to check for crevice corrosion. This type of corrosion occurs in the small gaps or crevices that may form between the flange and the pipe, especially in environments where moisture can be trapped. Slip-on flanges are particularly vulnerable due to their design, which creates an area where stagnant water can accumulate, leading to increased corrosion rates.

Detecting crevice corrosion is crucial because it can compromise the integrity of the flange and potentially lead to leaks or failures. Identifying this issue early through inspection plays a vital role in maintaining the safety and reliability of pressure vessels.

While checks for corrosion or erosion, holes or cracks, and thermal expansion are also important aspects of a comprehensive inspection, the specific focus on crevice corrosion highlights the unique challenges associated with slip-on flange designs and their operational environments.