Pumps (General) Flashcards
What is a pump?
A machine that adds energy to a liquid by increasing its velocity and/or increasing its pressure.
What are pumps classified as and how do they operate?
Pumps are classified as mechanical devices and are used to move liquids or gases utilising the suction of pressure to achieve this.
What are some uses of a pump?
Removing sewage from homes and businesses to waste treatment facilities.
Circulating heat transfer liquids through heating and cooling systems.
Mixing and transferring liquid components within chemical and industrial processes.
What are the two major types of pumps?
Positive Displacement and Centrifugal.
What are the 2 minor categories that positive displacement pumps fall under?
Single rotor and Multiple rotor.
What are the subcategories for the two minor categories for positive displacement pumps?
Single rotor: vane, piston, flexible member, and single screw.
Multiple rotor: gear, lobe, circumferential piston, and multiple screws.
What is the impeller?
The rotating part of the pump that gives the liquid energy.
What are the types of impellers?
Single suction enclosed, double suction enclosed and the single suction open impeller.
Describe single suction enclosed impeller.
Has only one tube where liquid can enter the impeller.
Describe double suction enclosed impeller and how is it better than single suction?
It allows liquid to enter both sides of the impeller and this creates high flows (volume,quantity) compared to the other.
Describe single suction open impellers?
Allows liquid to flow in one side of the impeller but has no enclosure.
What is true at the impeller region and the discharge region?
Impeller: high velocity, low pressure.
Discharge: lower velocity, high pressure.
What are pump curves and how do you use them.
Pump curves are graphs showing every operating point a pump can achieve. You can use them by finding the coordinates of flow rate and head pressure and seeing what curve it sits on.
On what axis are flow rate and head pressure?
The flow rate is the x-axis, and head pressure is the y-axis.
