The oil filling plug assembly ensures reliable lubrication in marine component manufacturing equipment. This critical part is installed in hydraulic systems and gearboxes used across shipbuilding and offshore machinery production lines. It provides a secure, leak-proof interface for oil refilling and maintenance, enabling technicians to perform routine servicing without disrupting production. In high-vibration environments typical of shipyard assembly areas, the plug’s robust design prevents accidental discharge and contamination. Its presence allows for consistent lubrication, reducing downtime and maintenance costs. The assembly is commonly found in gearboxes of cranes, winches, and propulsion systems, where precise lubrication is essential for prolonged operational life. By facilitating safe and efficient oil management, the plug supports the reliability of complex machinery used in constructing and maintaining marine infrastructure. It plays a vital role in ensuring smooth operation of test rigs and production lines, where consistent performance is paramount. In auxiliary systems such as hydraulic presses and conveyors, the plug enables quick access for maintenance, supporting the continuous flow of manufacturing processes.