Types of pumps

Types of pumps

1- Displacement pumps:
Reciprocating
Screw pump
Gears pump
2- Axial flow pumps
3- Centrafugal pumps:
Pump Classification According to Purpose and Principle of Operation

(A) PUMP CLASSIFICATION ACCORDING TO PURPOSE
In accordance with their purpose, shipboard pumps can be di¬vided into three groups:
1. General service pumps whose function is to ensure the sea¬worthiness of the ship and to provide for the domestic needs of the
•crew and passengers, and also to maintain the necessary sanitary conditions on board.
2. Pumps of the shipboard systems, designed to serve the main
•and auxiliary systems, and to facilitate the maintenance of normal conditions for their operation.
3. Special-purpose pumps in tankers, trawlers, ice-breakers, life-saving ships and dredgers. General service pumps include:
(1) bilge pumps,
(2) sanitary pumps,
(3) fire pumps,
(4) emergency pumps.

(B) PUMP CLASSIFICATION ACCORDING TO PRINCIPLE OF OPERATION
The following types are distinguished:
1. Static head, or potential energy, pumps,
2. Dynamic head, or kinetic energy, pumps.
The first group of pumps, which mainly create a static head or potential energy, are of the positive displacement type and in¬clude reciprocating and rotary pumps.
In addition to the static head, the pumps of the second group impart considerable dynamic head, or kinetic energy, to the liquid being handled. The part of the kinetic energy (dynamic head) re¬quired to deliver the liquid to its destination is transformed into potential energy (static head) in special parts of the pump designed for this purpose. In other words, velocity head is converted into pressure head.
The second group includes centrifugal, propeller and jet pumps.