Which type of pump typically includes a lantern ring?

A centrifugal pump typically includes a lantern ring as part of its design. The lantern ring is installed in the stuffing box of the pump's shaft seal. Its primary function is to provide a controlled path for lubrication and cooling fluid to flow around the shaft, helping to reduce wear on the packing material and prevent overheating. This is particularly important in centrifugal pumps, which often operate at higher speeds and generate more heat than other types.

In addition to the cooling and lubrication function, the lantern ring also aids in managing leakage by allowing a small amount of fluid to flow around the shaft while preventing excessive leakage into the environment. This is crucial for maintaining efficiency and safety in system operation.

Positive displacement pumps do not typically require a lantern ring since their operation is based on trapping a fixed volume of fluid and moving it through the system, which does not involve high rotational speeds like those seen in centrifugal pumps. Gear pumps and diaphragm pumps similarly have different sealing mechanisms that do not incorporate a lantern ring.