How does a transformer oil leakage arrester work?

A leakage arrester is typically a containment and diversion device, not an electrical arrester. It can be a seal or gland arrangement around vulnerable joints, bushings, or valves that captures small leaks and channels oil into a collection cup or drain line. Some designs add absorbent media and a visual indicator to show leakage early. The goal is to prevent oil from dripping externally, reduce environmental exposure, and provide time to schedule repairs before the leak becomes serious.