B1-2 Pumps And Compressors; Lubrication Flashcards
For quick starting, positive displacement standby pump will have:
A) the suction valve open and the discharge valve open
B) the vent and drain valves open
C) the suction valve and discharge valves closed
D) the suction valve open and the discharge closed
E) the suction valve closed and the discharge valve open
A) the suction valve open and the discharge valve open
Large centrifugal pumps should be started:
A) with the suction and discharge valves both open
B) with the suction and discharge valves both closed
C) with the suction and discharge valves 50% open
D) with the suction valve closed and the discharge valve open
E) with the suction valve open and the discharge valve closed
E) with the suction valve open and the discharge valve closed
Rotary and reciprocating pumps are examples of: A) turbine pumps B) regenerative pumps C) mixed flow pumps D) positive displacement pumps E) dynamic pumps
D) positive displacement pumps
Pumps that move a specific amount of liquid regardless of head include: A) mixed flow, volute and diffuser B) reciprocating, gear and rotary lobe C) centrifugal and rotary D) gear, lobe, diffuser, and mixed flow E) turbine and centrifugal
B) reciprocating, gear and rotary lobe
Pumps are generally classified into three groups, including: A) centrifugal, rotary and reciprocating B) reciprocating, gear and lobe C) gear, turbine and reciprocating D) turbine, rotary and lobe E) diffuser, reciprocating and rotary
A) centrifugal, rotary and reciprocating
The purpose of a diffuser in a centrifugal pump is to:
A) ensure the pump maintains its prime
B) change the pressure of the liquid to velocity
C) change the velocity of the liquid to pressure
D) counter balance the axial thrust of the impeller
E) reduce the pressure at the packing gland
C) change the velocity of the liquid to pressure
Volute, diffuser, axial flow, mixed flow and regenerative are all examples of: A) feedwater injector pumps B) rotary pumps C) reciprocating pumps D) centrifugal pumps E) positive displacement pumps
D) centrifugal pumps
The sum of pump static head and dynamic head is called the: A) total head B) combined head C) actually head D) friction head E) velocity head
A) total head
To reduce excessive leakage through the packing gland of a centrifugal water pump:
A) throttle the suction valve a little
B) tighten up the gland until all leakage has stopped
C) close down on the suction valve
D) tighten up the gland as far as possible
E) tighten up the gland to permit a slight amount of leakage
E) tighten up the gland to permit a slight amount of leakage
The inspection of an operating centrifugal water pump should ensure:
A) there is slight leakage from the stuffing boxes
B) the casing vent valve is partially open
C) the impeller is not rotating too rapidly
D) that the casing drain valve is partially open
E) that the suction valve is closed
A) there is slight leakage from the stuffing boxes
To reduce leakage between a pump shaft and casing, packing material is enclosed in a: A) seal cage B) packing chamber C) seal box D) casing box E) stuffing box
E) stuffing box
The purpose of a lantern ring in a centrifugal pump is to:
A) prevent moisture from entering the bearings
B) reduce the clearance between the impeller and the casing
C) carry oil from the sump to the bearing surface
D) secure the impeller to the pump shaft
E) prevent air leakage along the shaft
E) prevent air leakage along the shaft
Commonly used materials for pump wearing rings include: A) copper and Babbitt B) ceramic and stellite C) cast iron and bronze D) Teflon and PVC E) tool steel and stainless steel
C) cast iron and bronze
Typically, a centrifugal pump:
A) needs a lantern ring when “lifting” liquid
B) can lift water from very deep wells
C) can discharge water to a very high elevation with a single stage
D) will work well with a high negative suction head
E) is mainly used with lubrication systems
A) needs a lantern ring when “lifting” liquid
A major advantage of mechanical pump seals over packing is:
A) they are easily replaced when worn
B) they never wear out
C) they are less expensive
D) they do not result in shaft wear
E) they eliminate the need for sealing water when the pump is above the supply source
D) they do not result in shaft wear
The method of compressor control in which the motor runs constantly and air is compressed only between predetermined limits is called: A) constant acceleration control B) constant discharge control C) constant power control D) constant speed control E) constant pressure control
D) constant speed control
During startup, air compressors should be unloaded:
A) to prevent overloading of the motor
B) to prevent excessive stress on the compressor valves
C) to ensure proper operation of the suction valves
D) to ensure sufficient oil flow to compressor parts
E) to prevent cylinder overheating
A) to prevent overloading of the motor
An air compressor centrifugal unloader is used in conjunction with: A) free air unloader control B) suction unloader control C) start and stop control D) variable speed control E) constant speed control
C) start and stop control
A chemical typically utilized in compressed air dryers is: A) caustic soda B) hydrated lime C) silica gel D) sodium bicarbonate E) sodium sulphite
C) silica gel
The most suitable method of control for an air compressor that operates 25% of the time or less is: A) constant speed control B) suction unloader control C) free air unloader control D) start and stop control E) variable speed control
D) start and stop control
Inlet or discharge valves are NOT required on:
A) single acting compressors
B) single stage reciprocating compressors
C) double acting compressors
D) rotary lobe compressors
E) two stage reciprocating compressors
D) rotary lobe compressors
“Relative to a dry pipe fire system, an automatic air supply shall be connected so that proper pressure can be maintained in each system” is a statement of the:
A) Canadian standards association
B) industrial accident prevention association
C) society of municipal fire marshals
D) occupational health and safety
E) national fire protection association code
E) national fire protection association code
In an air compression system, a moisture separator:
A) is at the compressor suction and contains silica gel drying agent
B) is a centrifuge at the compressor suction
C) is immediately downstream from the after cooler
D) is a trap on the bottom of the receiver
E) is between the compressor and the after cooler
C) is immediately downstream from the after cooler
High capacity steam turbines should be lubricated with oils that: A) have a low pour point B) have a low specific heat C) mix well with water D) have a very high viscosity E) are fire resistant
E) are fire resistant
Oil additives:
A) are not a component of most lube oils
B) never lose their effect during use of the oil
C) will always affect the pour point greatly
D) should not significantly affect all other characteristics
E) should be used as little as possible
D) should not significantly affect all other characteristics
A semi solid lubricant: A) cannot be filtered B) can only be used for high temperature services C) has a low pour point D) requires complex handling equipment E) has low viscosity
A) cannot be filtered
Relative to lubrication, one place where wear is beneficial is:
A) on pump wear rings
B) on the oil pump sealing surfaces
C) new Babbitt bearing surfaces which wear smooth
D) in anti friction bearings
E) on the cylinder walls of internal combustion engines
C) new Babbitt bearing surfaces which wear smooth
A semi solid lubricant:
A) is not suitable for carrying away heat from bearings
B) does not provide suitable coating action for corrosion prevention
C) requires expensive handling equipment
D) is difficult to apply
E) is most suitable for journal bearing lubrication
A) is not suitable for carrying away heat form bearings
A semi solid lubricant: 1) has a high viscosity 2) seals out first and water from bearings 3) cannot be used for high temperature service 4) can be filtered A) 1,2,3 and 4 B) 1,2 and 4 C) 1,2 and 3 D) 3 and 4 E) 2,3 and 4
C) 1,2 and 3
Using compressed air to blow out a cleaned bearing:
A) should only be done in a well ventilated area
B) will result in distortion of the inside race
C) is the most effective method to remove impurities
D) will cause damage to the bearing due to corrosion
E) may have a sandblasting effect, causing pitting
E) may have a sandblasting effect, causing pitting
The lubricant for an anti friction bearing:
A) removes the load from internal components
B) must be cooled
C) could be either a semi solid lubricant or an oil
D) will separate the moving parts completely
E) prevents axial thrust
C) could be either a semi solid lubricant or an oil
A form of lubrication in which the slow speed surfaces are separated by only a very fine film of lubricant is: A) microscopic film lubrication B) rolling lubrication C) boundary lubrication D) fluid film lubrication E) fine film lubrication
C) boundary lubrication
Large journal or sleeve bearings have grooves:
A) in the non pressure area
B) cut in them for cooling purposes
C) in the high pressure area of e bearing Babbitt
D) for distributing lubricant evenly just after the pressure area
E) cut into the bearing housing
A) in the non pressure area
The pump used to supply water to plant washrooms and showers is called the: A) cooling water pump B) water closet pump C) safety water pump D) domestics water pump E) shower water pump
D) domestic water pump
Volute, diffuser, axial flow, mixed flow and regenerative are all examples of: A) reciprocating pumps B) centrifugal pumps C) feedwater injector pumps D) rotary pumps E) positive displacement pumps
B) centrifugal pumps
The vertical distance from the surface of a pump source of supply to the free surface of water in the discharge tank is the: A) total static head B) pressure head C) total head D) static friction head E) static discharge head
A) total static head
The pump used in high pressure, low capacity service would be: A) a diffuser centrifugal pump B) an injector C) a gear pump D) a centrifugal circulator pump E) a volute centrifugal pump
C) a gear pump
Regenerative pumps are also known as: A) injectors B) direct acting pumps C) mixed flow pumps D) turbine pumps E) centrifugal pumps
D) turbine pumps
The process in which vapour bubbles form and collapse causing a rapid succession of shock waves within a pumped liquid is called: A) embrittlement B) ambiosynthesis C) cavitation D) surge E) water hammer
C) cavitation
The purpose of a diffuser on a centrifugal pump it to:
A) change the velocity of the liquid to pressure
B) reduce the pressure at the packing gland
C) change the pressure of the liquid to velocity
D) counter balance the axial thrust of the impeller
E) ensure the pump maintains its prime
A) change the velocity of the liquid to pressure
Pumps that move a specific amount of liquid regardless of head include: A) centrifugal and rotary B) reciprocating, gear and rotary lobe C) turbine and centrifugal D) mixed flow, volute and diffuser E) gear, lobe, diffuser and mixed flow
B) reciprocating, gear and rotary lobe
To reduce excessive leakage through the packing gland of a centrifugal water pump:
A) tighten up the gland to permit a slight amount of leakage
B) tighten up the gland until all leakage has stopped
C) close down on the suction valve
D) tighten up the gland as far as is possible
E) throttle the suction valve a little
A) tighten up the gland to permit a slight amount of leakage
To prevent mechanical seal faces from becoming scored or grooved, make certain that:
A) the bearing oil sump is at least 50% full of lubricant
B) the coolant flow to the seal is adequate
C) the pump is equipped with a foot valve
D) the pump is always started with the suction valve closed
E) the pump is not operated at excessive discharge pressures
B) the coolant flow to the seal is adequate
The purpose of a lantern ring in a centrifugal pump is to:
A) prevent air leakage along the shaft
B) secure the impeller to the pump shaft
C) prevent moisture from entering the bearings
D) reduce the clearance between the impeller and the casing
E) carry oil from the pump to the bearing surface
A) prevent air leakage along the shaft
To prevent mechanical seal faces from becoming scored or grooved, make certain that:
A) the pump is equipped with a foot valve
B) the bearing oil sump is at least 50% full of lubricant
C) the casing drains are cracked open during startup
D) air is vented from the seal housing
E) the pump is not operated at excessive discharge pressures
D) air is vented from the seal housing
Pump wear rings are installed on an impeller by set screws, threading or: A) soldering B) welding C) forging D) shrinking E) waxing
D) shrinking
To prime a centrifugal pump: A) fill the discharge pipe with liquid B) fill the casing and suction line with liquid C) clean the oil ring D) bypass the impeller E) run the pump at half speed
B) fill the casing and suction line with liquid
Intercoolers:
A) must have a safety valve when used in positive displacement compressors
B) are used on all compressors
C) cool the air in the cylinders
D) are required to cool compressor lubricating oil
E) are more efficient when cooled with air than with water
A) must have a safety valve when used in positive displacement compressors
Velocity is converted to pressure in a centrifugal compressor: A) discharge pipe B) re directional vanes C) diffuser and casing D) impeller E) barrel casing
C) diffuser and casing
Sliding vane compressors: A) use cylinder valves B) are double acting compressors C) are of a positive displacement design D) are 100% efficient E) can develop pressures only up to 200 kPa
C) are of a positive displacement design
An auxiliary which will decrease an air compressor power requirements is the: A) variable compression ratio head B) diffuser C) after cooler D) intercooler E) receiver
D) intercooler
In an air compression system, a moisture separator:
A) is at the compressor suction and contains silica gel drying agent
B) is a centrifuge at the compressor suction
C) is between the compressor and the after cooler
D) is immediately downstream from the after cooler
E) is a trap on the bottom of the receiver
D) is immediately downstream from the after cooler
The compressor that would be used for large volume, low pressure applications would be the: A) single stage reciprocating B) single stage screw C) sliding vane D) multistage compressor E) single stage centrifugal
E) single stage centrifugal
The compressor with the lowest compression efficiency is the: A) single acting compressor B) double acting compressor C) two stage reciprocating compressor D) rotary lobe compressor E) single stage reciprocating compressor
D) rotary lobe compressor
“Relative to a dry pipe fire system, an automatic air supply shall be connected so that proper pressure can be maintained in each system,” is a statement of the:
A) occupational health and safety
B) Canadian standards association
C) industrial accident prevention association
D) national fire protection association code
E) society of municipal fire marshalls
D) national fire protection association code
Relative to lubrication, one place where wear is beneficial is:
A) new Babbitt bearing surfaces which wear smooth
B) on the cylinder walls of internal combustion engines
C) on the oil pump sealing surfaces
D) on pump wear rings
E) in antifriction bearings
A) new Babbitt bearing surfaces which wear smooth
For extremely low ambient air temperatures, the preferred lubricant is: A) paraffin based B) a semisolid C) a solid D) low viscosity liquid E) a high viscosity liquid
C) a solid
If oil viscosity changes greatly with little temperature change, then it will have a: A) high viscosity index B) low viscosity index C) high carbon residue D) low pour point E) high pour point
B) low viscosity index
Some of the purposes of a lubricant are: 1) friction reduction 2) wear reduction 3) corrosion reduction 4) surface reduction A) 1 and 3 only B) 1 and 2 only C) 2,3 and 4 only D) 1,2 and 3 only E) 1,2 and 4 only
D) 1,2 and 3 only
The oil for a refrigeration compressor:
A) must congeal at evaporator temperatures
B) must have a high flash point
C) must have a low pour point
D) must react chemically with the refrigerant
E) must have a high fire point
C) must have a low pour point
If you desire an oil to flow at a much lower temperature, you would likely add: A) a thickening agent B) pour point depressants C) a dispersant D) a viscosity index improver E) lower viscosity oil
B) pour point depressants
A thrust bearing that utilizes the oil wedge principle of lubrication is the: A) rotation thrust bearing B) collar thrust bearing C) vertical thrust bearing D) Bernoulli thrust bearing E) kingsbury thrust bearing
E) kingsbury thrust bearing
