B-02: Pumps And Compressors

Question 1

Which type of pump produces the greatest suction?

A. A volute centrifugal pump
B. A centrifugal pump
C. A regenerative pump
D. A positive displacement pump

Answer 1

D. A positive displacement pump

Question 2

Which method is NOT used to connect an electric motor to a compressor shaft?

A. Connected directly
B. Welding
C. V-Belts
D. Through a flywheel

Answer 2

B. Welding

Question 3

When a gland is tightened to stop leakage, what does the excessive heat caused by the friction do?

A. It melts the packing
B. It melts the shaft
C. It scores the shaft
D. It scores the packing

Answer 3

C. It scores the shaft

Question 4

Consider a pump that delivers liquid into the base of an overhead storage tank, from a reservoir situated below the pump. The vertical distance from the liquid surface up to the pump center line plus the vertical distance from the pump centre line up to the surface of the liquid in the discharge tank is:

A. Static discharge head
B. Static suction head
C. Total discharge head
D. Total static head

Answer 4

D. Total static head

Question 5

Preferably, dynamic pumps should be located _____ the liquid source.

A. Directly under
B. Above
C. At
D. Below

Answer 5

D. Below

Question 6

Centrifugal compressors:

A. Are used for his pressure and low flow
B. Could be of the multi-stage type
C. Must have a safety valve on the discharge when steam driven
D. Require inlet and discharge valves

Answer 6

B. Could be of the multi-storage type

Question 7

What is a disadvantage of compressed air tools?

A. They do not require insulation as they are cool to touch
B. Air transmission piping is more difficult to install then electric wiring
C. They are often lighter in weight
D. Air transmission piping is cheaper

Answer 7

B. Air transmission piping is more difficult to install than electrical wiring

Question 8

Reciprocating compressors can be single or double acting, depending on which factor?

A. Number of cylinders
B. Cylinder diameter
C. Cylinder design
D. Number of strokes of the piston

Answer 8

C. Cylinder design

Question 9

Single stage reciprocating air compressors have:

A. One or more cylinders of equal size
B. Variable speed drivers
C. Several cylinders, each of different sizes
D. Low power requirements

Answer 9

A. One or more cylinders of equal size

Question 10

Positive displacement compressors:

A. Cannot deliver pulsation-free air
B. Must have suction and discharge valves
C. Must all use internal lubrication
D. Could be single stage with three cylinders

Answer 10

D. Could be single stage with three cylinders

Question 11

Pumps are generally classified in which two categories ?

A. positive displacement and dynamic
B. Dynamic and rotary
C. Reciprocatingand rotary
D. Tri-plex and centrifugal

Answer 11

A. Positive displacement and dynamic

Question 12

The capacity of a centrifugal pump should only be reduced by:

A. Throttling the suction valve
B. Closing the suction valve
C. Opening the pump casing vent valve
D. Throttling the discharge valve

Answer 12

D. Throttling the discharge valve

Question 13

Which type of seal presents an intricate path that escaping gases must negotiate to reach atmosphere?

A. Dry Seal
B. Mechanical seal
C. Labyrinth seal
D. Carbon ring seal

Answer 13

C. Labyrinth seal

Question 14

A pump is capable of suction lift due to:

A. Its ability to convert kinetic energy into potential energy
B. The speed at which it operates
C. Its input power
D. Atmospheric pressure

Answer 14

D. Atmospheric pressure

Question 15

A speed-increasing gear is commonly used on:

A. Rotary lobe compressors
B. Screw compressors
C. Sliding vane compressors
D. Lobe compressors

Answer 15

B. Screw compressors

Question 16

When a pump discharges into a vessel operating at 300 kPa, the 300 kPa is referred to as:

A. Dynamic head
B. Pressure head
C. Discharge head
D. Friction head

Answer 16

B. Pressure head

Question 17

What is the head of a pumping system (without considering fluid velocity or friction of pipe, valves, and fittings)?

A. Static suction lift
B. Static head
C. Static discharge head
D. Discharge head

Answer 17

B. Static head

Question 18

It is generally accurate to say that:

A. 9.8 kPa pressure results from every metre of water depth or height
B. A water height or depth of 10.34 metre results in 1 kPa
C. 10.21 kPa Will results from 1 metre of static water head
D. 1 kPa Will result from a water head of 9.8 M

Answer 18

A. 9.8 kPa pressure results from every metre of water depth or height