Red Seal Exam Questions Answered Correctly Latest Update 2025-2026
How is cavitation immediately recognizable? - Answers Rattling sound and confirmed by low
pressure at pump inlet
What would you use a meter in valve for? - Answers Opposing loads
What is a metering out valve for - Answers tractive loads
In a barometer for every thousand feet of gain in altitude, how far does the column of Mercury
drop? - Answers 1 inch
How do positive displacement compressors work? - Answers Trapping the volume of gas and
reducing it by compressing it
How do dynamic compressors work? - Answers Increase the pressure by adding velocity
What are three things that pressure vessels must have? - Answers Gauge drain and safety relief
valve
What's the advantage of a labyrinth compressor? - Answers Runs without oil
What should you not do before inspecting a valve? - Answers Clean it
What causes valve flutter? - Answers Too much lift
What is the purpose of Rider bands? - Answers Support the weight of the piston and half the
weight of the rod
How do you set piston clearances if you don't have manufacturer specifications - Answers
Crank head clearance at 1/3 and head end clearance at 2/3
What temperature is the discharge temp held at for air cool compressors - Answers 88°C
At what discharge temperatures do you use thermo syphon cooling - Answers Between 88°C
and 121°C
What's the best option when changing capacity in a compressor? - Answers VVCP. Variable
volume clearance pocket.
What is the main purpose of an intercooler? - Answers Reduce horsepower requirement
In a compressor, how much hotter should the cooling water be the incoming gas temp? -
Answers 5.5°C hotter
Can a crew compressor deliver smooth pulsation, free air - Answers Yes
Does a dry screw or a wet screw need timing gears - Answers Dry screw
, What is the best method of capacity control on a screw compressor? - Answers Variable speed
control
What would you use a vein compressor for? - Answers Plant air or breathable air
What does the oil relief valve do in a vane compressor? - Answers Relieve oil on start up to
make sure hydraulic lock doesn't happen
What is the oil release valve do in a vane compressor - Answers Release oil on shut down
What does the vacuum relief valve do in a vane compressor? - Answers Prevent blade chatter
What would you use a liquid ring compressor for? - Answers Dirty gases without much
maintenance
What would you use a lobe blower compressor for? - Answers Large volume low pressure
What is the most used seal in dynamic compressors? - Answers Labyrinth seals
What is Stonewall? - Answers Occurs at low pressure and result in high flow
What is surge? - Answers Occurs at low flow causes high pressure
What's the safety factor for General rigging - Answers 5:1
What's the safety factor for lifting workers? - Answers 10:1
What's the safety factor for public elevators? - Answers 20:1
What is the basket hitch rated at? - Answers 2X
What is the choker hitch rated at? - Answers 3/4 X
What's the safety factor for chain? - Answers 4:1
How much stretch in a chain is allowed before you have to replace it - Answers 5%
How much is a wire rope allowed to shrink before it's replaced? - Answers 1/3 of its original
diameter
How should he set the angle of a ladder from vertical length to horizontal length - Answers 4:1
What height do you need guard rails? - Answers Above 3 m
What height do you need toe boards? - Answers Above 3.5 m
How low do you set foundations for grout? - Answers 3/4" to 1 1/2" deep
What grade surface plate is most common in a machine shop - Answers Grade B
How is cavitation immediately recognizable? - Answers Rattling sound and confirmed by low
pressure at pump inlet
What would you use a meter in valve for? - Answers Opposing loads
What is a metering out valve for - Answers tractive loads
In a barometer for every thousand feet of gain in altitude, how far does the column of Mercury
drop? - Answers 1 inch
How do positive displacement compressors work? - Answers Trapping the volume of gas and
reducing it by compressing it
How do dynamic compressors work? - Answers Increase the pressure by adding velocity
What are three things that pressure vessels must have? - Answers Gauge drain and safety relief
valve
What's the advantage of a labyrinth compressor? - Answers Runs without oil
What should you not do before inspecting a valve? - Answers Clean it
What causes valve flutter? - Answers Too much lift
What is the purpose of Rider bands? - Answers Support the weight of the piston and half the
weight of the rod
How do you set piston clearances if you don't have manufacturer specifications - Answers
Crank head clearance at 1/3 and head end clearance at 2/3
What temperature is the discharge temp held at for air cool compressors - Answers 88°C
At what discharge temperatures do you use thermo syphon cooling - Answers Between 88°C
and 121°C
What's the best option when changing capacity in a compressor? - Answers VVCP. Variable
volume clearance pocket.
What is the main purpose of an intercooler? - Answers Reduce horsepower requirement
In a compressor, how much hotter should the cooling water be the incoming gas temp? -
Answers 5.5°C hotter
Can a crew compressor deliver smooth pulsation, free air - Answers Yes
Does a dry screw or a wet screw need timing gears - Answers Dry screw
, What is the best method of capacity control on a screw compressor? - Answers Variable speed
control
What would you use a vein compressor for? - Answers Plant air or breathable air
What does the oil relief valve do in a vane compressor? - Answers Relieve oil on start up to
make sure hydraulic lock doesn't happen
What is the oil release valve do in a vane compressor - Answers Release oil on shut down
What does the vacuum relief valve do in a vane compressor? - Answers Prevent blade chatter
What would you use a liquid ring compressor for? - Answers Dirty gases without much
maintenance
What would you use a lobe blower compressor for? - Answers Large volume low pressure
What is the most used seal in dynamic compressors? - Answers Labyrinth seals
What is Stonewall? - Answers Occurs at low pressure and result in high flow
What is surge? - Answers Occurs at low flow causes high pressure
What's the safety factor for General rigging - Answers 5:1
What's the safety factor for lifting workers? - Answers 10:1
What's the safety factor for public elevators? - Answers 20:1
What is the basket hitch rated at? - Answers 2X
What is the choker hitch rated at? - Answers 3/4 X
What's the safety factor for chain? - Answers 4:1
How much stretch in a chain is allowed before you have to replace it - Answers 5%
How much is a wire rope allowed to shrink before it's replaced? - Answers 1/3 of its original
diameter
How should he set the angle of a ladder from vertical length to horizontal length - Answers 4:1
What height do you need guard rails? - Answers Above 3 m
What height do you need toe boards? - Answers Above 3.5 m
How low do you set foundations for grout? - Answers 3/4" to 1 1/2" deep
What grade surface plate is most common in a machine shop - Answers Grade B
