Reciprocating Pump vs Rotary Pump
Reciprocating pumps and rotary pumps are positive displacement pumps using two different mechanism to displace liquids. Pumps are devices that are used to move liquids sludge and gases from one place to another, mostly from underground to the surface of the earth. These pumps are either mechanical or electrical in nature. There are many types of pumps out of which we shall talk about positive displacement pumps which are further divided into reciprocating and rotary pumps. These are called positive displacement as they capture liquid on the suction side and move it to the discharge side using the principle of rotation. Rotating pump creates vacuum that draws in liquid. There is no air formation and there is no need to bleed air out of the lines. Let us find out the difference between reciprocating and rotary pumps.
Reciprocating pumps
These are positive displacement pumps (they transport matter with a moving object) that make use of diaphragm or a piston to displace liquids. They are called reciprocating because of a continuous backward and forward motion. Reciprocating pumps that use a piston do so by alternately drawing liquid or gas into a piston and then forcing it out through an exit valve. Diaphragm pumps also work in a similar manner using flexing of diaphragm. Reciprocating pumps progressively displace matter in a closed space by placing an obstruction in the form of a piston or a diaphragm.
Rotary pumps
These are also positive displacement pumps that cause displacement of liquid using the pressure of rotation. Pump moves at a great speed creating a vacuum that sucks liquid into the pump and throws it out through a discharge valve. These pumps can handle all types of liquids that do not have any solid content and are poor in transporting thick and viscous liquids. These pumps are simple in design and are very effective in conditions where centrifuges cannot be used economically. In places where changes in pressure are anticipated, rotary pumps are ideally suited. If the liquid that is to be transported is viscous, it is advisable to reduce the speed of the pump. The capacity of rotary pumps is not affected by changes of pressure on the side of the suction.