Section 1 - Pumps

Question 1

Name the two pump groups

Answer 1

Positive Displacement
Rotodynamic

Question 2

What are Positive Displacement pumps commonly used for

Answer 2

Used with oil,
Relatively low flow,
High pressure

Question 3

What are Rotodynamic pumps commonly used for

Answer 3

Water,
Relatively high flow,
Low pressure

Question 4

What types of pumps are Rotodynamic

Answer 4

Centrifugal,
Axial flow

Question 5

What type of centrifugal pumps are there

Answer 5

Volute,
Diffuser,
Both can be single and multi stage

Question 6

What kind of positive displacement pumps are there

Answer 6

Reciprocating,
Rotary

Question 7

List the most common types of positive displacement pumps

Answer 7

Reciprocating,
Gear pump,
Lobe pump,
Vane pump,
Screw pump,
Variable delivery piston pump (axial and radial)

Question 8

What do positive displacement pumps have in common

Answer 8

Normally self priming,
Discharge valves must be open prior to starting,
Relief valves are normally fitted

Question 9

What are the two forms of variable delivery piston pumps

Answer 9

Axial and radial

Question 10

List the pump characteristics of a variable delivery piston pump

Answer 10

Positive displacement,
Self priming,
Uni-directional,
Flow can be reversed,
Constant speed,
Pumping rate can be varied

Question 11

How can an axial piston pump flow rate be changed

Answer 11

By adjusting the angle of the swash plate as this determines the length of the piston stroke, therefore the capacity of the pump

Question 12

Explain a Positive Displacement pump

Answer 12

A type of pump that moves a fixed volume of fluid through its mechanical action, creating a continuous flow without relying on high velocity

Question 13

Explain a Reciprocating pump

Answer 13

A positive displacement pump that uses a piston or plunger to create pressure and move fluid by reciprocating back and forth within a cylinde

Question 14

Explain a Rotary pump

Answer 14

A positive displacement pump that uses rotating elements such as gears, lobes, or screws to transfer fluid from the inlet to the outlet

Question 15

Explain a Diaphragm pump

Answer 15

A type of positive displacement pump where a flexible diaphragm moves up and down, creating pressure variations to pump the fluid

Question 16

Explain a Screw pump

Answer 16

A positive displacement pump that uses inter meshing screws to move fluid axially, pushing it from the inlet to the outlet

Question 17

Explain a Rotodynamic pump

Answer 17

A type of pump that imparts energy to the fluid through a rotating impeller, converting mechanical energy into fluid flow velocity

Question 18

Explain a centrifugal pump

Answer 18

The most common type of rotodynamic pump, utilizing a rotating impeller to increase the fluid’s kinetic energy, causing it to be expelled from the pump’s outlet

Question 19

Explain a Axial Flow pump

Answer 19

A type of rotodynamic pump in which the fluid flows parallel to the pump shaft, generating lift due to the propeller-like action of the impeller

Question 20

Explain a Mixed flow pump

Answer 20

A hybrid of centrifugal and axial flow pumps, where the fluid flow exits both radially and axially, combining characteristics of both types

Question 21

Explain a Multistage pump

Answer 21

A rotodynamic pump with multiple impellers arranged in series, each imparting additional energy to the fluid, enabling it to handle higher pressures efficiently

Question 22

Explain a gear pump

Answer 22

A type of positive displacement pump that uses interlocking gears to move fluid between the gear teeth, generating a steady flow without pulsation

Question 23

Explain a Vane pump

Answer 23

A positive displacement pump employing sliding vanes inside a cylindrical rotor to create fluid movement and generate pumping action