Pumps

What are the types of Pumps?

Pumps are classified into 2 types – Rotodynamic Pumps & Positive Displacement Pumps.

1) Rotodynamic Pumps – where energy is continuously added to the liquid to accelerate its velocity.

An example of a Rotodynamic Pump is a Centrifugal Pump, where it uses kinetic energy to force fluid movement from one location to another through centrifugal force using impellers.
The Impeller designs are grouped as either radial flow, mixed flow, or axial flow depending on their hydraulic geometry.
Regenerative pumps, are centrifugal pumps but their impeller rotates in a ringlike channel with an inlet and an outlet opening.

2) A Positive Displacement Pump is where the pump is either reciprocating or rotary. In a positive displacement pump, energy is periodically added to the liquid by the direct application of force to one or more movable volumes of liquid.

Examples of a Positive Displacement Pump is a Diaphragm Pump or a Rotary Lobe Pump.
A diaphragm pump uses a combination of the reciprocating action of a rubber or teflon diaphragm and suitable non-return check valves to pump a liquid. Sometimes this type of pump is also called a membrane pump.

Rotary pumps are the most widely used positive displacement pumps and they are used to pump viscous liquids such as motor oil, syrup, and paint.
Reciprocating pumps are also among the oldest types of pumps used.

What is the difference between Industrial pumps & Chemical pumps?

Industrial pumps are process pumps which are normally used for clean /non-corroding fluids which may or may not contain solids i.e sewage.

Chemical pumps are process pumps which are generally designed for corrosive fluids, often at high temperatures and pressures. They may also contain small solids.