B1-10 Boiler Maintenance; Types Of Plants and B1-9 Flashcards
0
Q
A tap drill leaves sufficient material for the tap to produce: A) 60 percent of a full thread B) 75 percent of a full thread C) 80 percent of a full thread D) 90 percent of a full thread E) 100 percent of a full thread
A
B) 75 percent of a full thread
1
Q
When drilling a piece of plate steel using a drill press, the piece should be stopped from turning by:
A) securing it with clamps
B) affixing it to the table with contact cement
C) holding it firmly with your hands
D) using locking pliers to hold it
E) bolting a stop to the table
A
A) securing it with clamps
2
Q
A threading device stamped with the markings M4-0.7 is used for a thread diameter of: A) one quarter inch B) four inches C) 0.7 centimetres D) 4 millimetres E) 0.7 inches
A
D) 4 millimetres
3
Q
Internal threads into which bolts are screwed are cut into a hole using: A) drills B) clippers C) scribers D) taps E) dies
A
D) taps
4
Q
A file which has no teeth on the edges is called a: A) 2nd cut file B) dead smooth file C) safe edge file D) pillar file E) flat file
A
C) safe edge file
5
Q
In order to check the trueness of a flat surface, the piece should be set up on a: A) hermaphrodite calliper B) surface plate C) vernier calliper D) machinist square E) layout bench
A
B) surface plate
6
Q
A common lifting device consisting of an upper and lower set of pulleys connected with a single length of rope is called: A) a come along B) a block and tackle C) a shackle D) a chain block E) a differential pulley block
A
B) a block and tackle
7
Q
When raising or lowering an unevenly distributed load, the minimum number of slings required is: A) one B) two C) three D) four E) six
A
B) two
8
Q
Whenever two or more sling eyes are used in lifting an object, they should be:
A) fastened with a Crosby clip
B) spaced evenly, regardless of the object’s centre of gravity
C) held in a shackle
D) used only with a come along
E) of equal strength
A
C) held in a shackle
9
Q
When an equipment cover is provided with two eye bolts for lifting, the strain must be applied to both the bolts:
A) with exactly the same lifting force
B) using two hoists and a lifting bridle
C) in a vertical direction
D) using a single sling to avoid slippage
E) using two slings from a single crane hook
A
C) in a vertical direction
10
Q
One disadvantage of Saran rope is that it:
A) stretches more than other types
B) is not resistant to acids and solvents
C) has low abrasion resistance
D) has a low melting temperature
E) all of the above
A
D) has a low melting temperature
11
Q
An eye made in a wire rope using a Crosby clip will have a strength factor of: A) 50% B) 75% C) 80% D) 90% E) 95%
A
C) 80%
12
Q
To prevent damage to a work surface while fastening:
A) use toothed lock washers
B) use castle nuts only
C) use a lubricant during threading and tightening
D) use flat washers
E) do not over tighten a nut
A
D) use flat washers
13
Q
Machine bolts 8mm in diameter or larger are manufactured: A) only with fine threads B) only with hexagon heads C) with either coarse or fine threads D) only with square heads E) only with coarse threads
A
C) with either coarse or fine threads
14
Q
Overheating of boiler tubes may be caused by: 1) excessive firing rates 2) poor water circulation 3) heavy scale formation 4) low water level while firing 5) formation of soot on heating surfaces A) 1,3 and 4 only B) 1,2,3,4 and 5 C) 1,2,3 and 4 only D) 2,3,4 and 5 only E) 1,4 and 5 only
A
C) 1,2,3 and 4 only
15
Q
An open water tank should be attached to the vent connection during a wet boiler lay up in order to:
A) prevent water vapour from entering the power plant
B) hold the man way doors closed
C) permit the injection of chemicals
D) prevent air from entering as water volume changes
E) prevent wastage of chemicals
A
D) prevent air from entering as water volume changes
16
Q
Cracked tube ends on a fire tube boiler can represent a severe hazard because:
A) the tube may be forced out of the tube sheet by pressure inside the shell
B) the tubes provide structural support to the tube sheets, which is reduced by cracking
C) the cracked ends can cause flue gases to leak into the boiler room
D) cracks concentrate the corrosive effect of the flue gases
E) flue gases will become mixed with the boiler water
A
B) the tubes provide structural support to the tube sheets, which is reduced by cracking
17
Q
Before being allowed to weld on a boiler, a welder must have:
A) certain minimum number of years experience
B) performance qualification card
C) welding test conducted
D) certificate of qualification and a performance qualification card
E) certificate of qualification
A
D) certificate of qualification and a performance qualification card
18
Q
When laying up a boiler using a wet method, the fire side of the heating surface should be protected from corrosion by:
A) painting with an oil based protective paint
B) placing a desiccant material in the furnace
C) a thin oxide scale that builds up on the surface
D) applying a coat of mineral oil
E) the chemicals in the water used for lay up
A
D) applying a coat of mineral oil
19
Q
External boiler inspections can be carried out while the boiler is in service.
A) true
B) false
A
A) true
20
Q
Chemical cleaning of smaller boilers is not usually done because:
A) of the thin metal of which they are manufactured
B) the cost to do so is not warranted or justified
C) of the small surface area which the chemical contacts
D) it is impossible to get the chemical circulating adequately
E) they do not have adequate support for the high density of the chemicals
A
B) the cost to do so is not warranted or justified
21
Q
A relatively new and safer type of chemical used in boiler cleaning and treatment is: A) chelates B) hydrazine C) sodium hydroxide D) caustic soda E) tri sodium phosphate
A
A) chelates
22
Q
In a hot oil system, the oil temperature is controlled by the: A) oil level in heater B) load demand C) firing rate D) air flow E) stack temperature
A
C) firing rate
23
Q
Of the following hot oil direct heater types, the one that is most efficient is: A) combination conduction and convection B) conduction C) convection D) combination radiation and convection E) radiant
A
D) combination radiation and convection
24
```
The heaters in a hot oil system should be inspected every:
A) 3 months
B) 6 months
C) 12 months
D) 18 months
E) 24 months
```
C) 12 months
25
```
The solid formation produced when the oil breaks down as a result of overheating in a hot oil heater is called:
A) sludge
B) scale
C) coke
D) residual
E) residue
```
C) coke
26
The reason for leaving the suction valve on the standby pump of a hot oil system open is to:
A) keep the pump hot and ready for startup
B) prevent air bubbles from forming in the pump
C) prevent contaminants from blocking the suction strainer
D) ensure the safety valve protects the pump from excessive pressure
A) keep the pump hot and ready for startup
27
The raw material that is used in the largest quantity in the chemical pulping process is:
A) the chemicals used to produce the white liquor
B) water used in the manufacturing process
C) fuel used in the paper mill boilers
D) wood from which the pulp is produced
E) the limestone used to recover liquor chemicals
B) water used in the manufacturing process
28
```
In addition to black liquor, most Kraft pulp mills use power boilers which burn primarily:
A) natural gas
B) waste wood
C) bunker oil
D) propane
E) waste paper
```
B) waste wood
29
```
In a gas processing plant, the liquid hydrocarbons are removed from natural gas by the:
A) fuel gas treatment process
B) separation process
C) stabilization process
D) dehydration process
E) absorption process
```
B) separation process
30
In the recovery boiler furnace, black liquor is burned and:
A) sodium carbonate is converted to sodium hydroxide
B) sodium sulfate is reduced to sodium sulfite
C) calcium carbonate is converted to calcium oxide
D) sodium sulfate is reduced to sodium sulfide
E) calcium oxide is converted to calcium hydroxide
D) sodium sulfate is reduced to sodium sulfide
31
```
Production of 1 tonne of Kraft pulp results in the formation of approximately:
A) 120 kg of black liquor for firing
B) 320 kg of black liquor for firing
C) 540 kg of black liquor for firing
D) 930 kg of black liquor for firing
E) 1300 kg of black liquor for firing
```
E) 1300 kg of black liquor for firing
32
```
In a packing plant, the sides of a carcass of beef are cooled for 24 to 36 hours at approximately:
A) 5*C
B) 0*C
C) -5*C
D) -11*C
E) -25*C
```
D) -11*C
33
```
The refinery process of breaking down long chain oil molecules into shorter, more valuable molecules (like gasoline) is called:
A) vacuum distillation
B) centrifugal separation
C) hydro-treating
D) catalytic cracking
E) fractional distillation
```
D) catalytic cracking
34
```
After the logs are barked at a sawmill, the longer ones are cut down by a circular saw called a:
A) head saw
B) trim saw
C) chain saw
D) deck saw
E) gang saw
```
D) deck saw
35
```
Separating the various components in crude oil by vaporizing and, subsequently, condensing the fractions at different temperatures is called:
A) vacuum distillation
B) catalytic cracking
C) fractional distillation
D) centrifugal separation
E) hydro-treating
```
C) fractional distillation
36
```
Enthalpy of an air mixture measures the:
A) moisture content of the air mixture
B) total heat content of the air mixture
C) sensible heat content of the air mixture
D) latent heat content of the moist air
E) sensible heat content of the dry air
```
B) total heat content of the air mixture
37
```
The heat content of dry air is calculated using the base as:
A) 0*C
B) 4*C
C) 21*C
D) 25*C
E) 100*C
```
A) 0*C
38
```
The property of air that cannot be determined using a psychrometric chart is the:
A) dew point temperature
B) Enthalpy
C) partial pressure
D) specific volume
E) specific humidity
```
C) partial pressure
39
```
The unit of measurement for specific volume of air is:
A) kg/kg of dry air
B) kg/cubic meter of dry air
C) cubic meters/kg of dry air
D) cubic meters/cubic meter of dry air
E) kJ/kg of dry air
```
C) cubic meters/kg of dry air
40
```
In a process of simply raising the temperature of air without changing its moisture content, the heat added is:
A) latent heat and superheat
B) sensible heat only
C) latent heat only
D) sensible heat and superheat
E) sensible heat and latent heat
```
B) sensible heat only
41
Spray water used in cooling and humidification of air:
A) must have a small amount of sodium chloride added
B) must be cooled before use
C) must have a small amount of calcium chloride added
D) must be heated before use
E) does not require additional heating or cooling
E) does not require additional heating or cooling
42
```
During summer, an air conditioned space should ideally have a relative humidity of 50% and a dry bulb temperature of:
A) 21.4*C
B) 22.4*C
C) 23.4*C
D) 24.4*C
E) 25.4*C
```
D) 24.4*C
43
```
The time for a person's body to adjust when moving between spaces of varying temperature and humidity is called the:
A) thermal variance
B) shock effect
C) temperature/humidity variance
D) quench effect
E) thermal load ratio
```
B) shock effect
44
Properties of the tube axial fan include:
1) it is suitable for duct mounting
2) it discharges the air in a spiral motion
3) it is quite noisy in operation
4) it has widespread application in commercial air conditioning
A) 1,3 and 4 only
B) 1,2 and 3 only
C) 1 and 4 only
D) 2,3 and 4 only
E) 2 and 4 only
B) 1,2 and 3 only
45
A non overloading fan (backward inclined fan) characteristic means that the power curve on the performance diagram:
A) maintains almost a horizontal line
B) is maximum at shutoff and then falls off when approaching free delivery
C) continuously rises or falls depending on the air temperature
D) continuously rises from shutoff to free delivery
E) rises from shutoff to a maximum and then falls off when approaching free delivery
E) rises from shutoff to a maximum and then falls off when approaching free delivery
46
Select the statement about a tube axial fan that is false:
A) it is suitable for use in industrial air conditioning
B) it is widely used in commercial air conditioning
C) it is quite noisy in operation
D) it has the ability to move large volumes of air
E) friction losses are higher than centrifugal fans
B) it is widely used in commercial air conditioning
47
```
In an air conditioning system, the pressure that overcomes the resistance of the ducts, filters, etc, is:
A) dynamic pressure
B) velocity pressure
C) static pressure
D) partial pressure
E) total pressure
```
C) static pressure
48
Which of the following is not a function of terminal air distribution devices?
A) distribute the air to the spaces
B) create local pockets of still air
C) provide uniform space temperatures
D) control or counteract the effects of conduction, convection and radiation
E) provide adequate air motion
B) create local pockets of still air
49
```
In air conditioning duct systems, the device that functions similarly to a check valve is the:
A) Louvre
B) relief damper
C) manual damper
D) two position damper
E) modulating damper
```
B) relief damper
50
In an air conditioning duct system, the most effective location for installing sound absorbing lining is:
A) in the middle section of a run of the duct
B) at the point the duct enters the control space
C) in the suction and discharge plenum of the fan
D) 6m from where a quiet location is located
E) near the terminal devices of the ducts
C) in the suction and discharge plenum of the fan
51
```
In an air conditioning system, the supply and the return air ducts are classified based on the air's:
A) volume and total pressure
B) velocity and volume
C) velocity and pressure
D) velocity pressure and total pressure
E) volume and static pressure
```
C) velocity and pressure
52
```
Coils with finned surfaces will experience reduced heat transfer efficiency when the fins are:
A) exposed to lower temperatures
B) exposed to higher air flows
C) crimped
D) closely spaced
E) poorly bonded to the tubes
```
E) poorly bonded to the tubes
53
```
The coil circulating design that produces a high heat transfer capacity with a limited water quantity is the:
A) full circuiting design
B) half serpentine design
C) double serpentine design
D) triple serpentine design
E) single serpentine design
```
B) half serpentine design
54
```
The fin spacing recommended for steam and hot water heating coils is:
A) 8-14 fins per inch
B) 4-8 fins per inch
C) 3-8 fins per inch
D) 2-4 fins per inch
E) 4-14 fins per inch
```
E) 4-14 fins per inch
55
```
In air conditioning coils, the extended surfaces provided by the fins are called:
A) bare surface
B) primary surface
C) contact surface
D) tertiary surface
E) secondary surface
```
E) secondary surface
56
Heating coil steam trap recommendations include:
1) trap all of the coils from a common header
2) type of trap depends on pressure differential and capacity
3) pitch condensate piping from trap to header 21mm/m
4) always install a strainer near the trap inlet
A) 3 and 4 only
B) 1,3 and 4 only
C) 2,3 and 4 only
D) 1,2,3 and 4
E) 1,2 and 3 only
C) 2,3 and 4 only
57
```
The preferred steam trap for installation on air conditioning heating coils operating at lower pressures (below 172kPa) is the:
A) float and thermostatic type
B) thermodynamic type
C) thermostatic type
D) impulse type
E) inverted bucket type
```
A) float and thermostatic type
58
The effects of using ethylene glycol in a hot water heating coil include:
1) a lower heat transfer rate
2) better protection against freezing
3) increased friction losses in the coil and piping
4) a requirement for a large pump with more horsepower
A) 2,3 and 4 only
B) 1 and 4 only
C) 1 and 3 only
D) 1,2,3 and 4
D) 1,2,3 and 4
59
Which of the following statements about vacuum breakers is false?
A) vacuum breakers are essential for satisfactory functioning of the steam trap
B) the vacuum breaker must be installed before the control valve and as near as possible to the outlet connection of the coil
C) pipe connections of check valves used as vacuum breakers may be left open to the atmosphere
D) they are used to prevent freeze ups caused by negative pressure in the coil
E) pipe connections of check valves used as vacuum breakers may be connected to the return header
B) the vacuum breaker must be installed before the control valve and as near as possible to the outlet connection of the coil
60
When air temperature is raised without the addition of water vapour to the air, the relative humidity will:
A) increase
B) increase or decrease depending on air movement
C) decrease
D) not change
C) decrease
61
An atomizing humidifier is typically regulated by:
A) a timer that controls the spray pump
B) a timer that controls a solenoid valve on the supply water line
C) a humidistat that controls a solenoid valve on the supply water line
D) a humidistat that controls the supply fan
E) a humidistat that controls the spray pump
C) a humidistat that controls a solenoid valve on the supply water line
62
When the outdoor temperature falls to below -25*C, the recommended relative humidity inside a home should be maintained at:
A) less than 10%
B) greater than 30%
C) greater than 50%
D) a slightly lesser value than where condensation starts to appear on window glass
E) at a much greater value than where condensation starts to appear on window glass
D) a slightly lesser value than where condensation starts to appear on window glass
63
```
A small air conditioning unit with DX coils, condenser, fans and controls all located in a closed casing that only provides air filtration, cooling, ventilation and dehumidification is called a:
A) window air conditioner
B) central conditioning unit
C) packaged air conditioner
D) rooftop air conditioner
E) fan coil unit
```
A) window air conditioner
64
The central air conditioning system with constant air volume supplied to the conditioned space which can provide both heating and cooling simultaneously is called a:
A) hot and cold deck system
B) multizone system
C) constant air volume, terminal reheat high velocity system
D) constant air volume, terminal reheat low velocity system
E) single zone system
B) multizone system
65
The space thermostat in each zone on a simple multizone system:
A) regulates the modulating damper of the mixing compartment
B) controls the mixing box
C) controls the hot water temperature to the coil
D) regulates the total makeup air into the system
E) controls the chilled water temperature to the coil
A) regulates the modulating damper of the mixing compartment
66
```
The four (4) possible arrangements of the intake section of an air handling unit are:
A) full recirculation, mixed air, supply air, and fixed percent outdoor air
B) full recirculation, mixed air, exhaust air and supply air
C) 100% outdoor air, mixed air, fixed percentage outdoor air, and full recirculation
D) 100% outdoor air, mixed air, exhaust air, and fixed percentage outdoor air
```
C) 100% outdoor air, mixed air, fixed percentage outdoor air, and full recirculation
67
```
Which of the following statements for a forced air system used in a residential home is false?
A) can provide cooling
B) can provide humidification
C) can provide ventilation
D) can provide natural gas heating
E) can provide multizone control
```
E) can provide multizone control
68
Fan coils with a makeup air system utilize a central system to provide:
A) 100% recirculated air and heating control
B) filtration, air mixing and air temperature control
C) filtration, air mixing and humidity control
D) 50% fresh air and humidity control
E) 100% fresh air and humidity control
E) 100% fresh air and humidity control
69
Solar loading in different zones is countered by:
1) use of larger capacity coils
2) provision of separate control zones for each building face
3) boosting the volume of air supplied to each zone
4) using different "changeover temperatures" for each zone
5) use of a separate primary air reheat schedule
A) 1,2 and 3 only
B) 3,4 and 5 only
C) 2,4 and 5 only
D) 1,2,3,4 and 5
E) 2,3 and 4 only
C) 2,4 and 5 only
70
```
The similarity between a constant air volume system with perimeter heating and a variable air volume system with perimeter heating is that the supplied air is controlled at:
A) 12.5*C
B) 25*C
C) 15*C
D) 20*C
E) 18*C
```
A) 12.5*C
71
The property by which an induction air conditioning system gets its name is:
A) the type of units in each zone
B) the way the air in the room is circulated
C) the types of AHU employed
D) the methods by which chilled water circulates through cooling coils
E) the air intake method used in the control AHU
B) the way the air in the room is circulated
72
A heat recovery system that operates in subfreezing temperatures is likely to have ice formation on the:
A) mixing valve
B) recovery coils and preconditioning coil
C) recovery coils
D) none of the coils because ethylene glycol is used as the heat transfer medium
E) preconditioning coils
C) recovery coils
73
```
The system that makes use of a coil installed underground below frost levels is called:
A) an underground runaround system
B) an earth to air heat pump
C) a thermal induction system
D) a heat pipe
E) a thermal earth wheel
```
B) an earth to air heat pump
74
A hygroscopic wheel is a heat recovery device in which:
A) moisture is produced
B) heat absorbing segments are filled with desiccant impregnated material
C) latent heat only is transferred
D) cross contamination is eliminated
E) glycol is pumped through circular coils
B) heat absorbing segments are filled with desiccant impregnated material
75
One of the disadvantages of a runaround system for heat recovery is:
A) a larger space requirement than other systems
B) a high temperature difference must be maintained between exhaust air and outdoor air
C) high maintenance costs
D) the possibility of cross contamination
E) the system is not very adaptable to retrofit applications
B) a high temperature difference must be maintained between exhaust air and outdoor air
76
By tilting the evaporator section of a heat pipe recovery unit below the horizontal, the heat recovery rate of the system will be:
A) reduced
B) increased
C) unchanged
B) increased
77
On typical ventilation control systems, when the supply fan is stopped, the position of the dampers should be:
A) outdoor air damper and return air damper are open, exhaust air damper is closed
B) outdoor air damper and exhaust air damper are 25% open, return air damper is 50% open
C) outdoor air damper, exhaust air damper, and return air dampers are all closed
D) outdoor air damper, exhaust air damper, and return air dampers are all open
E) outdoor air damper and exhaust air dampers are closed, return air damper is fully open
E) outdoor air damper and exhaust air dampers are closed, return air damper is fully open
78
When preheat coils are used to heat the outdoor air, the mixed air temperature is usually controlled to no more than 18*C to avoid:
A) overheating the water in the air washer
B) under heating the hot water in the heating coils
C) prevent excessive biological growth in the humidifier
D) overheating the water in the cooling coils
E) overheating the air in the controlled space
E) overheating the air in the controlled space
79
Dehumidification often leads to an uncomfortable dry bulb temperature in the controlled space. To overcome this difficulty:
A) install a reheat coil with modulating thermostat
B) install a modulating humidistat
C) raise the temperature of the DX coil
D) cycle the compressor on and off
E) supply a reduced amount of outdoor makeup air
A) install a reheat coil with modulating thermostat
80
Static air pressure in the ducting of an air conditioning system must be controlled:
A) to ensure acceptable noise levels and air flow patterns
B) to maintain humidity at desired levels
C) to reduce boiler fuel consumption
D) to prevent moisture condensation in the ducts
E) so that desired zone temperatures are achieved
A) to ensure acceptable noise levels and air flow patterns
81
```
The minimum amount of outside air required to replace stale air in a commercial building is:
A) 50%
B) 30%
C) 20%
D) 15%
E) 5%
```
D) 15%
82
```
The forcing of air into a building by means of a fan is called:
A) infiltration
B) ventilation
C) purging
D) exhaustion
E) ventilation load
```
B) ventilation
83
```
To calculate the heat gains from fluorescent lighting, add the wattage ratings and multiply by a factor of:
A) 0.6
B) 0.9
C) 1.2
D) 1.5
E) 2.0
```
C) 1.2
84
The ventilation load on a building is:
A) the total amount of leakage into the building
B) the percentage opening of the outside air dampers
C) the a,punt of makeup air required to remove smoke, odours, etc.
D) the additional heat load on the air conditioning equipment due to infiltration and ventilation
E) the rated capacity of the supply air fan
D) the additional heat load on the air conditioning equipment due to infiltration and ventilation
85
```
The quantity of heat flow from all mechanisms, in unit time, under the conditions prevailing at that time is called:
A) thermal tranmittance
B) thermal transmission
C) thermal resistance
D) radiance
E) thermal conductivity
```
B) thermal transmission
