What is the purpose of using mechanical seals on modern tankers?

The purpose of using mechanical seals on modern tankers is primarily to prevent leakage to the bilge. Mechanical seals create a robust barrier that effectively contains liquids, thereby minimizing the risk of hazardous substances leaking into areas where they could cause environmental harm or safety hazards. This is especially critical on tankers that transport various liquids, including petroleum products, where spills can lead to significant ecological damage and legal repercussions.

By sealing the join between rotating and stationary parts, mechanical seals ensure that the fluid being transported stays contained within the system, preventing it from inadvertently escaping into the bilge areas of the vessel. This contributes not only to environmental protection but also enhances the safety of the ship and its crew by reducing the chance of fire or explosion associated with leaking flammable liquids.

While enhanced pumping efficiency, increased pressure in the system, and reduced operational costs may have some relevance in tank operations, they do not capture the primary function of mechanical seals, which is to ensure the containment of substances being transported.