In most cases, the choice of the appropriate driver for a gas compressor is ultimately determined by the:
A - Type or source of available power B - Nature of the gas being compressed C - Compression ratio of the compressor D - Horsepower requirements
Correct Answer(s): A
Question 5:
Pulling vacuum on compressor cylinders is recommended during start-up because it allows air to enter through packing and achieve maximum compression efficiency in a shorter time.
A - True B - False
Correct Answer(s): B
Question 6:
A turbocharger may increase the output of a given engine by as much as:
A - 50% B - 30% C - 90% D - 15%
Correct Answer(s): A
Question 7:
Induction motors are simple, rugged and reliable, and have no:
A - Moving parts B - Rotating windings C - Limit to the applications for which they may be used D - Bearings requiring lubrication
Correct Answer(s): B
Question 8:
An engine exhaust temperature controller is affected by:
A - Fuel gas consumption B - Crankcase pressure C - Air-to-fuel ratio D - Lube oil pressure
Correct Answer(s): C
Question 9:
The most widely used compressor driver in the low power range is the:
A - Gas turbine B - Steam turbine C - Synchronous motor D - Squirrel cage induction motor
Correct Answer(s): D
Question 10:
Compressor cylinders operating on bypass may:
A - Heat up B - Cause hydrates to form C - Damage the governor D - Result in warping cylinder parts
Correct Answer(s): A
Question 1:
By definition, a dynamic compressor involves:
A - An intermittent flow of a gas from a low velocity to a high-pressure area B - Trapping a set volume of a gas inside a space and then forcing it out at a higher pressure C - The continuous flow of a gas with the conversion of velocity energy into pressure energy D - The continuous flow of a gas into and out of a reciprocating cylinder
Correct Answer(s): C
Question 2:
Centrifugal compressors have the advantage of:
A - Having a higher efficiency compared to positive displacement compressors B - Being simple and rugged in construction C - Requiring internal lubrication D - Being well suited for low capacity work
Correct Answer(s): B
Question 3:
If you were setting up an axial compressor that was driven by an internal combustion engine, what would you need to add for the compressor to perform to design?
A - Additional stages B - Speed-increasing gears C - Speed-reducing gears D - A higher torque camshaft
Correct Answer(s): B
Question 4:
The thrust that is produced on the rotor of an axial compressor:
A - Results in a force that tends to push the rotor toward the discharge end B - Is balanced by the shape of the blades C - Can be overcome by installing a dummy piston on the compressor shaft D - Is an insignificant factor in compressor design
Correct Answer(s): C
Question 5:
In an axial compressor, the shortest blades on the stator are located:
A - On the upper casing of the unit B - At the inlet end of the unit C - At the outlet end of the unit D - At the middle of the unit
Correct Answer(s): C
Question 6:
In an axial compressor, when the gas passes through the fixed blades, its pressure is further increased by conversion of:
A - Velocity B - Discharge rate C - Suction D - Volume
Correct Answer(s): A
Question 7:
The two types of thrust bearings used in axial compressors are designed to:
A - Reduce corrosion of the compressor blades B - Absorb the axial thrust that is directed toward the discharge end of the rotor C - Align the stator with the impellers D - Absorb the axial thrust that is directed toward the inlet end of the rotor
Correct Answer(s): D
Question 8:
A major advantage of a horizontally split compressor casing is that:
A - The casing is a one-piece design allowing for maximum velocity to pressure conversion B - The upper casing can be removed for maintenance functions C - A gasket is used to seal the upper and lower casings D - The casing seal is metal to metal
Correct Answer(s): B
Question 9:
In a centrifugal compressor, the diffuser vanes work to:
A - Accelerate the flow of gas into the eye of the impeller B - Increase gas pressure between the impeller outlet and the volute casing C - Increase gas pressure just before it leaves the volute casing of the compressor D - Reverse the direction of flow as the gas leaves the impeller, reducing the pressure
Correct Answer(s): B
Question 10:
Elevating the output pressures of centrifugal compressors by multi-staging means that:
A - The diffuser vanes are placed at both the inlet and outlet of an impeller B - The gas is compressed in steps as it passes progressively through several impellers mounted on a common shaft C - A low-pressure compressor discharges into the suction of a high-pressure compressor D - Several sets of diffusers are placed at the outlet of a single impeller
Correct Answer(s): B
Question 1:
In an axial compressor, when the gas passes through the fixed blades, its pressure is further increased by conversion of:
A - Velocity B - Suction C - Discharge rate D - Volume
Correct Answer(s): A
Question 2:
In an axial compressor, a stage consists of a/an:
A - Set of intake and a discharge valves B - Pair of moving and fixed blade rows C - Seal and a fixed blade row D - Impeller shaft and a stator
Correct Answer(s): B
Question 3:
The two types of thrust bearings used in axial compressors are designed to:
A - Absorb the axial thrust that is directed toward the inlet end of the rotor B - Absorb the axial thrust that is directed toward the discharge end of the rotor C - Align the stator with the impellers D - Reduce corrosion of the compressor blades
Correct Answer(s): A
Question 4:
Centrifugal compressors do not require internal lubrication.
A - True B - False
Correct Answer(s): A
Question 5:
By definition, a dynamic compressor involves:
A - The continuous flow of a gas into and out of a reciprocating cylinder B - An intermittent flow of a gas from a low velocity to a high-pressure area C - The continuous flow of a gas with the conversion of velocity energy into pressure energy D - Trapping a set volume of a gas inside a space and then forcing it out at a higher pressure
Correct Answer(s): C
Question 6:
In an axial compressor, the longest blades on the stator are located at the:
A - Middle B - Outlet end C - Casing D - Inlet end
Correct Answer(s): D
Question 7:
Centrifugal compressors have the disadvantage of:
A - Requiring internal lubrication B - Being mechanically complex C - Having lower efficiencies compared to positive displacement compressors D - Being subject to corrosion and erosion to a greater extent than axial compressors
Correct Answer(s): C
Question 8:
Centrifugal compressors have the disadvantage of:
A - Not being well suited for low capacity work B - Requiring internal lubrication C - Being mechanically complex D - Having high maintenance requirements
Correct Answer(s): A
Question 9:
Labyrinths and carbon rings are devices commonly used on centrifugal compressors and provide the same function as:
A - Inlet guide vanes B - Stator blade adjusters C - Mechanical seals D - Thrust bearings
Correct Answer(s): C
Question 10:
The thrust that is produced on the rotor of an axial compressor:
A - Can be overcome by installing a dummy piston on the compressor shaft B - Is an insignificant factor in compressor design C - Is balanced by the shape of the blades D - Results in a force that tends to push the rotor toward the discharge end
Correct Answer(s): A
Question 1:
The impeller of a centrifugal compressor can be equipped with vanes at the eye shaped in such a way:
A - That allows for the control of the capacity of the unit B - That the operating characteristics of the compressor can be adjusted C - That the axial thrust which is directed toward the inlet end of the impeller is absorbed D - To provide shockless entry to the impeller
Correct Answer(s): D
Question 2:
In an axial compressor, a stage consists of a/an:
A - Seal and a fixed blade row B - Impeller shaft and a stator C - Pair of moving and fixed blade rows D - Set of intake and a discharge valves
Correct Answer(s): C
Question 3:
Axial compressor casings are made of:
A - Steel B - Galvanized steel C - Wrought iron D - Aluminum Correct Answer(s): A
Question 4:
In an axial compressor, each pair of moving and fixed blade rows constitutes:
A - A stage B - A pressure reduction C - An impeller shaft D - A seal
Correct Answer(s): A
Question 5:
Centrifugal compressors have the disadvantage of:
A - Having high maintenance requirements B - Not being well suited for low capacity work C - Being mechanically complex D - Requiring internal lubrication
Correct Answer(s): B
Question 6:
In an axial compressor, the shortest blades on the stator are located:
A - On the upper casing of the unit B - At the inlet end of the unit C - At the outlet end of the unit D - At the middle of the unit
Correct Answer(s): C
Question 7:
Elevating the output pressures of centrifugal compressors by multi-staging means that:
A - A low-pressure compressor discharges into the suction of a high-pressure compressor B - The gas is compressed in steps as it passes progressively through several impellers mounted on a common shaft C - Several sets of diffusers are placed at the outlet of a single impeller D - The diffuser vanes are placed at both the inlet and outlet of an impeller
Correct Answer(s): B
Question 8:
Compared to centrifugal compressors, to achieve given pressure differentials, axial compressors require:
A - Lower volumes B - Higher temperatures C - More stages D - Fewer stages
Correct Answer(s): C
Question 9:
In an axial compressor, the longest blades on the stator are located at the:
A - Casing B - Middle C - Outlet end D - Inlet end
Correct Answer(s): D
Question 10:
Two-stage centrifugal compressors are commonly used in:
A - Large volume, high pressure applications B - Low volume, low pressure applications C - Low volume, high pressure applications D - Large volume, low pressure applications
Correct Answer(s): D
Question 1:
Centrifugal compressors have the disadvantage of:
A - Being mechanically complex B - Requiring internal lubrication C - Not being well suited for low capacity work D - Having high maintenance requirements
Correct Answer(s): C
Question 2:
In a centrifugal compressor, the diffuser vanes work to:
A - Reverse the direction of flow as the gas leaves the impeller, reducing the pressure B - Increase gas pressure between the impeller outlet and the volute casing C - Accelerate the flow of gas into the eye of the impeller D - Increase gas pressure just before it leaves the volute casing of the compressor
Correct Answer(s): B
Question 3:
Centrifugal compressors have the advantage of:
A - Having a higher efficiency compared to positive displacement compressors B - Being simple and rugged in construction C - Requiring internal lubrication D - Being well suited for low capacity work
Correct Answer(s): B
Question 4:
If you were setting up an axial compressor that was driven by an internal combustion engine, what would you need to add for the compressor to perform to design?
A - Additional stages B - A higher torque camshaft C - Speed-reducing gears D - Speed-increasing gears
Correct Answer(s): D
Question 5:
In an axial compressor, a stage consists of a/an:
A - Pair of moving and fixed blade rows B - Set of intake and a discharge valves C - Seal and a fixed blade row D - Impeller shaft and a stator
Correct Answer(s): A
Question 6:
In an axial compressor, each pair of moving and fixed blade rows constitutes:
A - A seal B - A pressure reduction C - An impeller shaft D - A stage
Correct Answer(s): D
Question 7:
The thrust that is produced on the rotor of an axial compressor:
A - Is balanced by the shape of the blades B - Results in a force that tends to push the rotor toward the discharge end C - Is an insignificant factor in compressor design D - Can be overcome by installing a dummy piston on the compressor shaft
Correct Answer(s): D
Question 8:
Axial compressor casings are made of:
A - Galvanized steel B - Wrought iron C - Aluminum D - Steel
Correct Answer(s): D
Question 9:
In an axial compressor, the shortest blades on the stator are located:
A - At the middle of the unit B - At the outlet end of the unit C - At the inlet end of the unit D - On the upper casing of the unit
Correct Answer(s): B
Question 10:
Compared to centrifugal compressors, to achieve given pressure differentials, axial compressors require:
A - Fewer stages B - Lower volumes C - More stages D - Higher temperatures
Correct Answer(s): C
Question 1:
The impeller of a centrifugal compressor can be equipped with vanes at the eye shaped in such a way:
A - That allows for the control of the capacity of the unit B - To provide shockless entry to the impeller C - That the operating characteristics of the compressor can be adjusted D - That the axial thrust which is directed toward the inlet end of the impeller is absorbed
Correct Answer(s): B
Question 2:
If you were setting up an axial compressor that was driven by an internal combustion engine, what would you need to add for the compressor to perform to design?
A - Additional stages B - A higher torque camshaft C - Speed-increasing gears D - Speed-reducing gears
Correct Answer(s): C
Question 3:
The thrust that is produced on the rotor of an axial compressor:
A - Can be overcome by installing a dummy piston on the compressor shaft B - Is an insignificant factor in compressor design C - Results in a force that tends to push the rotor toward the discharge end D - Is balanced by the shape of the blades
Correct Answer(s): A
Question 4:
In an axial compressor, the shortest blades on the stator are located:
A - At the outlet end of the unit B - At the middle of the unit C - On the upper casing of the unit D - At the inlet end of the unit
Correct Answer(s): A
Question 5:
The two types of thrust bearings used in axial compressors are designed to:
A - Absorb the axial thrust that is directed toward the discharge end of the rotor B - Align the stator with the impellers C - Absorb the axial thrust that is directed toward the inlet end of the rotor D - Reduce corrosion of the compressor blades
Correct Answer(s): C
Question 6:
Axial compressor casings are made of:
A - Wrought iron B - Galvanized steel C - Aluminum D - Steel
Correct Answer(s): D
Question 7:
Two-stage centrifugal compressors are commonly used in:
A - Large volume, high pressure applications B - Low volume, low pressure applications C - Low volume, high pressure applications D - Large volume, low pressure applications
Correct Answer(s): D
Question 8:
A major advantage of a horizontally split compressor casing is that:
A - The casing is a one-piece design allowing for maximum velocity to pressure conversion B - The casing seal is metal to metal C - The upper casing can be removed for maintenance functions D - A gasket is used to seal the upper and lower casings
Correctness Rule: Single Correct Answer Required
Answer(s) Given: C Correct Answer(s): C Marked as: Correct
_______________________________________________
Question 9:
Centrifugal compressors have the advantage of:
A - Being simple and rugged in construction B - Requiring internal lubrication C - Having a higher efficiency compared to positive displacement compressors D - Being well suited for low capacity work
Correctness Rule: Single Correct Answer Required
Answer(s) Given: A Correct Answer(s): A Marked as: Correct
_______________________________________________
Question 10:
Elevating the output pressures of centrifugal compressors by multi-staging means that:
A - A low-pressure compressor discharges into the suction of a high-pressure compressor B - The diffuser vanes are placed at both the inlet and outlet of an impeller C - Several sets of diffusers are placed at the outlet of a single impeller D - The gas is compressed in steps as it passes progressively through several impellers mounted on a common shaft
Correctness Rule: Single Correct Answer Required
Answer(s) Given: D Correct Answer(s): D Marked as: Correct
Question 1:
Labyrinths and carbon rings are devices commonly used on centrifugal compressors and provide the same function as:
A - Stator blade adjusters B - Thrust bearings C - Mechanical seals D - Inlet guide vanes
Correctness Rule: Single Correct Answer Required
Answer(s) Given: C Correct Answer(s): C Marked as: Correct
_______________________________________________
Question 2:
In an axial compressor, a stage consists of a/an:
A - Pair of moving and fixed blade rows B - Set of intake and a discharge valves C - Impeller shaft and a stator D - Seal and a fixed blade row
Correctness Rule: Single Correct Answer Required
Answer(s) Given: A Correct Answer(s): A Marked as: Correct
_______________________________________________
Question 3:
In an axial compressor, the shortest blades on the stator are located:
A - At the inlet end of the unit B - On the upper casing of the unit C - At the middle of the unit D - At the outlet end of the unit
Correctness Rule: Single Correct Answer Required
Answer(s) Given: D Correct Answer(s): D Marked as: Correct
_______________________________________________
Question 4:
Centrifugal compressors do not require internal lubrication.
A - True B - False
Correctness Rule: Single Correct Answer Required
Answer(s) Given: A Correct Answer(s): A Marked as: Correct
_______________________________________________
Question 5:
The thrust that is produced on the rotor of an axial compressor:
A - Is balanced by the shape of the blades B - Can be overcome by installing a dummy piston on the compressor shaft C - Is an insignificant factor in compressor design D - Results in a force that tends to push the rotor toward the discharge end
Correctness Rule: Single Correct Answer Required
Answer(s) Given: B Correct Answer(s): B Marked as: Correct
_______________________________________________
Question 6:
Two-stage centrifugal compressors are commonly used in:
A - Large volume, low pressure applications B - Low volume, high pressure applications C - Low volume, low pressure applications D - Large volume, high pressure applications
Correctness Rule: Single Correct Answer Required
Answer(s) Given: A Correct Answer(s): A Marked as: Correct
_______________________________________________
Question 7:
Centrifugal compressors have the disadvantage of:
A - Requiring internal lubrication B - Being mechanically complex C - Having high maintenance requirements D - Not being well suited for low capacity work
Correctness Rule: Single Correct Answer Required
Answer(s) Given: D Correct Answer(s): D Marked as: Correct
_______________________________________________
Question 8:
Compared to centrifugal compressors, to achieve given pressure differentials, axial compressors require:
A - More stages B - Fewer stages C - Higher temperatures D - Lower volumes
Correctness Rule: Single Correct Answer Required
Answer(s) Given: A Correct Answer(s): A Question 1:
An aftercooler on a reciprocating compressor:
A - Increases the weakening of parts due to high temperatures B - Condenses both oil and water from the compressed gas C - Reduces the level of liquids in the scrubber by operating the dump valve D - Increases the possibility of explosions of oil vapour mixed with air
Correctness Rule: Single Correct Answer Required
Answer(s) Given: B Correct Answer(s): B Marked as: Correct
_______________________________________________
Question 2:
Intercoolers are never equipped with a safety valve, pressure gauges and thermometers on the compressed gas and cooling water piping.
A - True B - False
Correctness Rule: Single Correct Answer Required
Answer(s) Given: B Correct Answer(s): B Marked as: Correct
_______________________________________________
Question 3:
The large surface area provided within a horizontal separator allows for:
A - Lower equipment cost when compared to vertical separators B - Optimum release of trapped gas C - Optimum retention of trapped gas D - Ease of liquid level control
Correctness Rule: Single Correct Answer Required
Answer(s) Given: B Correct Answer(s): B Marked as: Correct
_______________________________________________
Question 4:
Gas compressor intercoolers should be equipped with:
A - A coalescing section B - A safety valve C - Mist extractors D - Vents
Correctness Rule: Single Correct Answer Required
Answer(s) Given: B Correct Answer(s): B Marked as: Correct
_______________________________________________
Question 5:
The heat exchanger on the discharge of the compressor following the completion of compression is called the:
A - Intercooler B - Vortex breaker C - Hot mist extractor D - Aftercooler
Correctness Rule: Single Correct Answer Required
Answer(s) Given: D Correct Answer(s): D Marked as: Correct
_______________________________________________
Question 6:
To reduce the gas temperature between states of a gas compressor a/an ___________ is utilized.
A - intercooler B - aftercooler C - separator D - mist extractor
Correctness Rule: Single Correct Answer Required
Answer(s) Given: A Correct Answer(s): A Marked as: Correct
_______________________________________________
Question 7:
Which of the following is not a result of cooling the gas with an intercooler and/or aftercooler:
A - Removal of water and oil vapours from the gas stream B - More effective cylinder lubrication C - Increased the amount of power required to compress the gas D - Reduces weakening of parts due to high temperatures
Correctness Rule: Single Correct Answer Required
Answer(s) Given: C Correct Answer(s): C Marked as: Correct
_______________________________________________
Question 8:
Because their configuration provides a __________________ the use of horizontal separators allows for optimal release of trapped gas.
A - superior control of process temperatures B - reduced surface area C - greater degree of level control D - greater surface area
Correctness Rule: Single Correct Answer Required
Answer(s) Given: D Correct Answer(s): D Marked as: Correct
_______________________________________________
Question 9:
In separator vessels, regardless of shape or capacity, the secondary section uses:
A - A pad made up of knitted wire mesh, or a series of cyclonic passages B - The effects of the centrifugal force of the inlet stream to separate liquids from the gas C - A sump to collect all liquids removed from the gas D - The force of gravity to help separate entrained droplets of liquid from the stream
Correctness Rule: Single Correct Answer Required
Answer(s) Given: D Correct Answer(s): D Marked as: Correct
_______________________________________________
Question 10:
The major section of the separator vessel labeled "D" in the diagram below is referred to as the:
A - Coalescing section B - Sump (liquid collection) section C - Primary separation section D - Secondary or gravity section
Correctness Rule: Single Correct Answer Required
Answer(s) Given: B Correct Answer(s): B Marked as: Correct
Question 1:
Gas compressor intercoolers should be equipped with:
A - Vents B - A coalescing section C - A safety valve D - Mist extractors
Correctness Rule: Single Correct Answer Required
Answer(s) Given: C Correct Answer(s): C Marked as: Correct