Marine pumps refer to the different pumps that are used on ships. All marine pumps must meet certain specifications of the shipbuilders society before they can be approved for use on ships.
Large amounts of air need to be pumped out on ships, for this reason, most marine pumps do not require manual priming before they can operate. They are self-priming pumps and need little or no manual manipulation to function.
Most marine pumps are designed in the centrifugal pump style in order for them to function in different capacities on the ship. Boiler feed pumps are marine pumps that transfer the required quantity of water to a steam generator or nuclear reactor. The amount of water the boiler feed pump transfers should be directly proportional to the quantity of steam emitted. Boiler feed pumps are usually located in the engine room of a ship.
The condensate pump is another type of marine pump that is also a centrifugal pump. As the name implies it transports condensed steam by converting it to water. Condensate pumps function either in an open circuit or closed circuit. In an open circuit system, the pump would transfer the condensed steam in the form of water into a tank, but in the closed-circuit system, the water is transferred to the boiler pump instead of a tank. The suction strength of a condensate pump can be improved by installing an impeller for the suction stage. Reducing the speed at which the pump rotates also enhances its suction strength.
Transverse thrusters are propeller pumps used on ships as well, so they fall under the category of marine pumps. They Are usually present in the bow of the ship and are responsible for pumping out water to control the direction the propeller of the ship moves. When the propeller pumps water through the transverse tunnel in a particular direction, it causes the ship to turn in the opposite direction of the water.
There is also the cooling water marine pump. This type of pump makes use of either freshwater or seawater to cool down the ship in case of excess heating.
Cargo oil pumps are used on the ship to pump out excess oil when the ship gets to its destination port. This pump pumps the oil out of the ship’s tank and into a tank on land at the ship port. During the pumping process when the oil is still full, the inlet of the pump widens to make space for the volume of oil being sucked through the pipes, then as the amount of oil reduces, the suction becomes higher and the inlet deflates. At this stage, special equipment is used to remove the air to prevent it from getting into the pump.
The bilge pump is also another type of marine pump that is used to remove excess water which tends to accumulate at the lowest part of a ship.
Fire fighting pump as the name implies is used to pump water used for fighting fires on ships. They can either be stationary or transportable. The transportable fire fighting pumps are self-priming centrifugal pumps and can either be single-stage or multi-stage. The stationary fire fighting pumps on ships usually require manual priming before they can function.
Other types of marine pumps include the ballast pump and dock pump. Most marine pumps have a vertical and radially split design due to the inadequate space found on ships. The motor of the pump is usually mounted directly on the pump.