Which type of tube rupture occurs due to prolonged overheat conditions?

The correct answer is thick-lipped rupture, which occurs due to prolonged overheat conditions. This type of rupture typically manifests when the material's strength is compromised by extended exposure to high temperatures. As the tube becomes overheated, it can cause the material to lose its ductility and strength, leading to a rupture characterized by a thick lip or edge around the break. This phenomenon often occurs in systems where there is inadequate cooling or excessive heat generation, potentially resulting in catastrophic failure if not properly managed.

The other types of ruptures have different characteristics. Thin-lipped ruptures often involve more brittle materials that fail under stress without the prolonged exposure to heat contributing to the fracture. Longitudinal and transverse fractures represent the direction in which a tube fails, generally influenced by mechanical stress or pressure rather than extended heat exposure. Understanding these distinctions is critical for diagnosing tube failures and implementing preventative maintenance strategies.