HWGS gas seals typically consist of a stationary seal ring and a rotating seal ring. The seal faces of these rings are usually made of a hard material like silicon carbide or carbon graphite, which provides a smooth, wear-resistant surface. The seal faces are kept apart by a thin film of gas, which is supplied under pressure to the seal chamber. This gas film prevents direct contact between the seal faces, reducing friction and wear, and thereby extending the life of the seal.

The Plan 53B system is a closed loop piping system that circulates and isolates liquids between sealed double seal arrangements to cool and lubricate the inner and outer seals. The system provides circulation through an internal pump ring and uses a heat exchanger to remove heat.