Marine pumps refer to various pumps that meet the requirements of ship regulations and technical conditions for ship use. On ships, they are often used to transport various liquids such as seawater, fresh water, sewage, lubricating oil, and fuel. To achieve this goal, it is necessary to increase the pressure energy, potential energy, or overcome the resistance of liquid flow in the pipeline of the transported liquid. Therefore, fundamentally, pumps are equipment used to increase the mechanical energy of the liquid.

According to different purposes, marine pumps can be divided into:

Pumps for marine power

There are fuel pumps, lubricating oil pumps, seawater pumps, fresh water pumps, hydraulic pumps for steering gear or other hydraulic deck machinery, feedwater pumps for boiler installations, cooling water pumps for refrigeration installations, seawater pumps and condensate pumps for seawater desalination plants, etc.

Marine general pumps

There are bilge pumps, ballast pumps, fire pumps, daily fresh water pumps, daily seawater pumps, and hot water circulation pumps; There are also general-purpose pumps that can be used as ballast, firefighting, and bilge pumps.

Special ship specific pumps

Some special purpose ships also have specialized pumps set up for their special operational requirements, such as cargo pumps for oil tankers, mud pumps for dredgers, salvage pumps on fishing vessels, water jet propulsion pumps on water jet propulsion vessels, and fishing pumps on net less fishing vessels.

According to the different working

principles of pumps, there are mainly the following types of marine pumps:

Displacement pump

Positive displacement pumps suck and discharge liquids by periodically increasing or decreasing the working volume caused by the movement of working components. When the working volume increases and the pressure decreases, the liquid is sucked in. When the working volume decreases and the pressure increases, the liquid is discharged, and the pressure of the liquid is directly increased by compression.

Impeller pump

Vane type pumps rely on the impeller to drive the liquid to rotate at high speed, continuously generating suction and discharge effects, transferring mechanical energy to the conveyed liquid, increasing the pressure of the liquid, and achieving the purpose of conveying the liquid.

Jet pump

Jet pumps rely on the working fluid with a certain pressure to generate a high-speed jet in the nozzle to inject fluid, and then increase the energy of the injected fluid through momentum exchange.

According to the position of the pump shaft, it is divided into vertical pumps and horizontal pumps;

Divided into single suction pumps and double suction pumps according to the number of suction ports;

According to the prime mover of the driving pump, it is divided into electric pump, steam pump, and diesel engine pump.

Generally, pumps are named after their functions on ships, such as the main seawater cooling pump and the main lubricating oil pump.