Definition - What does Pack Rust mean?
Pack rust is a type of corrosion and corrosion product that occurs due to atmospheric conditions within restricted spaces, such as crevices and joints of metallic components.
This term is important because it is used in the study of corrosion damage and protective coatings required for joints, metallic plates and other components that are packed to form vital structures, such as road and railway bridges.
Corrosionpedia explains Pack Rust
Pack rust refers to an electrochemical reaction that results in rust formation within the joints and packs of ferrous metal sheets and components of different structures. The term is also used during bridge inspection to report and explain the parts of bridges displaying the signs of deterioration by rust packed in between steel plates and joints.
Rusting occurs due to electrochemical reactions. Normal rust does not cause bulging and distortion, but a significant pack rust feature is the bulging of parts of parallel plates. If the problem is not resolved, structural strength will reduce continuously, creating potentially serious failures.
Pack rust mainly affects ferrous materials. To prevent pack rust, the surfaces must be treated with rust-preventive coatings at the time of component and plate assembly.
If pack rust affects a structure, the rust must be removed.