Week 5 Test Questions with
Answers
What type of control is used when compressor demand varies between 60% and 100%
capacity? - Answer-Modulation control
What are the 3 types of components used to physically alter the displacement of a
compressor? - Answer-- Turn valves
- Poppet valves
- Slide valves
The 3 types of valves that are used for displacement control operate on the same
principle which is to let some of the air in the compression chamber cycle back into the
to the suction without being compressed. True or False? - Answer-True
What is the purpose of variable volume ratio control on a screw compressor? - Answer-
To save power
What determines the pressure ratio that the screw compressor delivers? - Answer-The
discharge port location
How does a screw compressor deliver smooth, pulsation free flow of gas? - Answer-
Staggering the lobes and flutes
What are the 3 main types of capacity control used on screw compressors? - Answer--
Suction throttling
- Rotating speed
- Displacement control
What is the most common method of suction throttling control? - Answer-Load/ No load
What are the 2 modes of the load/no load control and what are the positions of the inlet
valve on each? - Answer-Mode 1: Fully loaded/ open inlet valve
Mode 2: Fully unloaded/ Closed inlet valve
When does a compressor reach its built in pressure ratio? - Answer-Just before it
discharges