If the mechanical energy is converted into hydraulic energy (or pressure energy) by sucking the liquid into a cylinder in which a piston is reciprocating (moving backwards and forwards), which exerts the thrust on the liquid and increases its hydraulic energy (pressure energy), the pump is known as reciprocating pump
Main ports of a reciprocating pump
1.A cylinder with a piston, piston rod, connecting rod and a crank,
2. Suction pipe
4. Suction valve and
Slip of Reciprocating Pump
Slip of a reciprocating pump is defined as the difference between the theoretical discharge and the actual discharge of the pump.
Characteristic Curves Of Reciprocatring Pumps
1.According to the water being on contact with one side or both sides of the piston
(i.) Single acting pump (ii.) Double-acting pump
2.According to the number of cylinders provided
(i.) Single acting pump (ii.) Double-acting pump (iii.) Triple-acting pump
Reciprocating pumps Vs centrifugal pumps
The advantages of reciprocating pumps in general over centrifugal pumps may be summarized as follows:
1. They can be designed for higher heads than centrifugal pumps.
2. They are not subject to air binding, and the suction may be under a pressure less than atmospheric without necessitating special devices for priming.
3. They are more flexible in operation than centrifugal pumps.
4. They operate at nearly constant efficiency over a wide range of flow rates.
The advantages of centrifugal pumps over reciprocating pumps are:
1. The simplest centrifugal pumps are cheaper than the simplest reciprocating pumps.
2. Centrifugal pumps deliver liquid at uniform pressure without shocks or pulsations.
3. They can be directly c onnected to motor derive without the use of gea rs or belts.
4. Valves in the discharg e line may be completely closed without injurin g them.
5. They can handle liquid s with large amounts of solids in suspension.