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140 Cards in this Set
- Front
- Back
The most efficient operation of a fan demands that the ________ is only sufficient enough to supply the required amount of air. |
speed |
|
Balanced draft refers to the combination of _________ and ___________ draft. |
forced, induced |
|
A boiler with only an induced draft fan will have a ________ furnace pressure |
negative |
|
When the least amount of energy is desired to drive a fan with variable output control, the type of control used would most likely be _________ speed coupling. |
variable |
|
A diaphragm draft gauge on a furnace typically indicates the draft in __________ of water column. |
millimetres |
|
Which code specifies standards for the air openings required into a boiler room when the boiler is burning oil? |
CSA B-139.1 |
|
The advantages of a steel stack over a reinforced concrete stack is that a steel stack is a lower ________. |
cost |
|
Draft measuring instruments can be used to measure wind box pressure, air heater flue gas pressure and ____________ pressure. |
furnace |
|
Natural draft is produced in a boiler furnace when gasses in the stack have _________ mass than an equal column of outside colder air. |
less |
|
If a "U" tube is connected to the discharge of a forced draft fan the open end will have a _________ liquid level than the connection to the fan. |
higher |
|
When the least amount of energy is desired to drive a fan with variable output control, the type of control used would most likely be a ___________ speed coupling. |
variable |
|
In a balanced draft system, the forced draft fan is __________ than the induced draft fan. |
smaller |
|
The most efficient operation of a fan demands that the __________ be only sufficient enough to supply the required amount of air. |
speed |
|
Proper draft is important to the plant operator because it produces ________ combustion. |
efficient |
|
In a balanced draft system the air heater is placed __________ the ID fan and boiler and ___________ the forced draft fan and boiler. |
between, between |
|
Variable speed couplings require the ________ amount of energy when the fan is operating at varying speeds. |
least |
|
Inlet damper control on a fan requires ______ power to drive the fan at reduced loads. |
less |
|
An induced draft fan operates at much __________ temperatures than an FD fan. |
higher |
|
With a fan outlet damper control the fan air pressure ____________ with a decrease in air flow. |
increases |
|
The inclined "U" tube manometer is __________ accurate than a "U" tube manometer. |
more |
|
With axial flow fan the air flow is __________ to the shaft. |
parallel |
|
The incomplete combustion of carbon results in the formation of ___________. |
CO |
|
The amount of air required to supply just enough oxygen for complete combustion is called ___________ air. |
theoretical |
|
The approximate amount of excess air for burning fuel oil is ____% |
15% |
|
Carbon monoxide is both explosive and _________. |
toxic |
|
A disadvantage of coal compared to oil is that more handling equipment and _________ is required. |
labour |
|
When using a mechanical fuel oil atomizer, ________ pump pressure is required. |
high |
|
Ethane is a component of natural gas and constitutes a percent volume of ____% - ____%. |
10% - 20% |
|
When using a Fyrite Analyzer it is recommended to use _____ bulb strokes to capture a _____ ml sample. |
18, 60ml |
|
The main function of a gas burner is to provide _________ of gas with combustion air. |
mixing |
|
Boiler stack temperature can rise if the __________ of the boiler becomes fouled. |
fireside |
|
Insufficient air for combustion will result in:
_________ in flue gasses ______ oxygen reading in flue gases ______ CO in flue gases |
carbon, low, high |
|
A major disadvantage of oil over coal is that oil is more ___________ and less abundant. |
expensive |
|
When a gas fired burner is burning fuel properly, it will have a ________ flame with short ________ coloured tips. |
blue, yellow |
|
The approximate amount of excess air for fuel oil is ____% |
15% |
|
In a steam atomizing oil burner, the _______ travels through the central portion of the burner. |
oil |
|
The __________ atomizing burner supplies oil under high pressure. |
mechanical |
|
If not enough air is given to an oil fired flame, the flame will be _______ and smokey. |
dark |
|
The amount of excess air required for combustion is determined by the composition and ___________ of the fuel. |
condition |
|
The three combustible elements of a fuel are: |
Hydrogen, Carbon & Sulphur |
|
__________ is added to the coal in a typical FBC unit to ensure that the heated compounds become relatively inert. |
limestone |
|
NOx emissions are reduced in a fluidized bed furnace due to the ___________ combustion temperatures. |
reduced |
|
In atmospheric fluidized bed combustion units, the fuel content by mass of the turbulent inert material is usually less than _____% |
2% |
|
The combustion in a fluidized bed combustion unit can be controlled at a furnace temperature of _______˚C to reduce NOx emissions. |
850˚C |
|
Before coal can be burned in a fluidized bed combustion unit, it is necessary to heat the inert bed material to about _________˚C |
600˚C |
|
A typical time to heat the bed in a fluidized bed combustion unit to fuel-ignition temperature is ____ hour(s) |
1 hour |
|
One major disadvantage of FBC is it will not work with __________ in the coal. |
sulphur |
|
A design disadvantage of the application of a PFBC furnace is _________ and/or corrosion/fouling of turbine blades may occur. |
erosion |
|
Reducing furnace bed temperatures from 1600˚C to 850˚C reduces as well the production of __________ oxides. |
nitrous |
|
What is the ignition temperature of coal? |
600˚C |
|
Steam generators of the FBC type can be reduced in size by up to ____% |
25% |
|
A gradual loss of the fluidized bed, including fuel (carbon) particles, is due to ____________. |
carryover |
|
Fluidized bed combustion is a term describing a _________ of systems of combustion. |
range |
|
One major disadvantage of FBC is there is poor combustion _________ at low firing rates. |
control |
|
The pressurized combustion chamber allows the use of more efficient _________ cycles. |
energy |
|
What is the percentage of SO2 reduction which can be gained by adding an excess amount of limestone to the bed of an AFBC unit? ( ____% - ____%) |
80% - 90% |
|
Large "clinkers" are not produced in FBC furnaces because of the __________ furnace temperatures. |
lower |
|
For coal containing 5% sulphur, how much limestone might be fed to the furnace of an AFBC unit with each tonne of coal? |
1/2 tonne |
|
Two start-up strategies of an FBC unit are:
1. Combustion of auxiliary fuel as a flame ________ the bed fluidized with air.
2. Passing hot gasses through the ______. |
above, bed |
|
Operating a PFBC furnace at low temperatures results in the __________ temperature limited over the period of heat supply. |
steam |
|
The growth of the bed can be controlled by __________ feed rate and bed _________ rate. |
limestone, drain |
|
Because of the one quarter reduction size of FBC plants a significant saving is gained in __________ and construction cost. |
material |
|
The ASME code states that if a steam boiler has over _________ m2 of water heating surface, two or more safety valves shall be installed. |
47 |
|
If a safety valve opens, the boiler pressure will not rise more than ______% above the MAWP |
6% |
|
The purpose of the spring in a safety valve is to hold down the ______ on the seat. |
disc |
|
Each safety valve on a steam heating boiler is set to discharge at a pressure not exceeding _____ kPa |
100 kPa |
|
The safety valves on a boiler meet code requirements and are set to a popping pressure of 1380 kPa. What would be the maximum permissible pressure rise in the boiler, if the boiler was fired at full capacity with the main steam valve closed? (kPa) |
82.8 kPa |
|
When performing a safety valve pop test, one of the first things to do is verify the __________ of the applicable steam pressure gauge. |
accuracy |
|
If the safety valve of a boiler is set at 200kPa, then the steam gauge dial must be graduated from 0 kPa - ________ kPa. |
400kPa |
|
A steam heating boiler safety valve shall be set to discharge at a pressure no greater than ______ kPa. |
103 |
|
An operator should check that a boiler safety valve will open at its set pressure by ___________ the boiler pressure until the valve opens and noting the pressure on the pressure gauge when the valve opened. |
increasing |
|
In order for a person to adjust the opening pressure or popping point of a safety valve, they must be authorized by a boiler _____________. |
inspector |
|
The minimum blowdown of an LP safety valve is _____ kPa. (ASME Section IV) |
15 kPa |
|
A fitting which is not clearly identified should be ___________. |
rejected |
|
Temperature relief devices can open on a rise in temperature by the expansion of a wax-filled rod or by the ________ of the alloy in a fusible plug. |
melting |
|
Two safety valves are required on a high pressure steam boiler that has a heating surface larger than _____ m2 |
47 m2 |
|
LP boiler safety valves can be repaired by a qualified boiler operator after permission from the ____________. |
inspector |
|
If a safety valve is too small then the boiler pressure will rise more than ____% above the MAWP. |
6% |
|
A safety relief valve is like a safety valve except it does not have a ____________ ring or bottom guides |
blowdown |
|
A temperature relief valve uses the expansion of a ______ filed rod. |
wax |
|
The opening or connection between a heating boiler safety valve and the boiler shall have __________ the same area as the valve inlet. |
at least |
|
What does the boiler inspector install to prevent tampering with a safety valve setting? |
a seal |
|
If a power boiler has 60 square meters of heating surface, it must have _____________ safety valves. |
at least two |
|
When is a stop valve allowed between the safety valve and the boiler drum? |
never |
|
The "popping" action of a safety valve is due to the __________-shaped lip on the valve disc. |
cone |
|
An LP steam boiler safety valve shall not be smaller than ____mm |
13mm |
|
The safety valve test lever must not be used unless pressure is at least ____% of Boiler Operating pressure. |
75% |
|
The purpose of the spring in a safety valve is to hold down the ______ on the seat. |
disc |
|
If gauge glass breaks, the first action by the operator should be to close the gauge glass _________ valves. |
isolation |
|
Tubular gauge glasses should not exceed _____ mm in length. |
750 mm |
|
For a horizontal firetube boiler with a diameter greater than 400 mm, ASME code, Section 1, requires the lowest visible level in the gauge glass to be at least ______ mm above the lowest permissible water level as specified by the boiler manufacturer. |
75 mm |
|
Round tubular gauge glasses are not recommended for pressures aboue ________ kPa |
2800 kPa |
|
According to the codes, each gauge glass shall be fitted with a drain cock or valve having an unrestricted drain opening of not less than ____mm diameter to facilitate cleaning. |
6 mm |
|
Quick-closing gauge glass valves require ____ degrees for full travel. |
90˚ |
|
The bottom of the gauge glass for a heating boiler must be ______ mm above the lowest permissible water level. |
25mm |
|
flat gauge glasses are lined with mica to prevent ________ of the glass. |
erosion |
|
According to the codes, gauge glasses on power boilers having multiple tubular sections shall have a minimum of _____ mm overlap of the sections in which the water level may be visible. |
25 mm |
|
According to the codes, connections from the power boiler to the water column shall be at least ______ mm. |
25 mm |
|
Dirp traps are installed on an "Igema" remote water-level indicator to prevent indicating liquid ___________. |
contamination |
|
A disadvantage of gauge glass safety-shutoff valve is it requires more __________. |
maintenance |
|
If gauge glass breaks, the first action by the operator should be to close the the _______ glass isolating valves. |
gauge |
|
When a differential pressure is used to measure water level in a boiler steam drum, the differential pressure is greatest when the drum level is ______. |
low |
|
When a fire tube boiler is filled for the first time, it should be confirmed that when the waster first appears in the gauge glass, that there is ______ mm of water over the top of the tubes. |
76 mm |
|
The bottom of the gauge glass for a fire tube boiler must be ______ mm above the highest fire tube. |
76 mm |
|
For pressure above 2410 kPa, a water column is constructed of __________. |
steel |
|
Try cocks are for __________ water level while the gauge glass is out of service. |
checking |
|
A great advantage of an Igema level indicator over a Hopkinson unit is there are no _________ parts. |
moving |
|
A gauge glass may be surrounded by a number of thin rods, when the boiler is a high pressure unit, the glass is attached to a _________ column. |
water |
|
According to the codes, if shut-off valves are installed on a water column, they are to be sealed in the open position and must be ____________ screw and yoke rising spindle gate valves. |
outside |
|
According to the codes, connections for gage glasses connected directly to the power boiler or to an intervening water column shall be at least ____ mm. |
15mm |
|
According to the codes, a power boiler water column must have a drain connection of at least ______ mm. |
20mm |
|
According to the codes connections from the power boiler to the water column shall be at least _______ mm. |
25mm |
|
According to the codes, if shutoff valves are provided in the pipe connections between a power boiler and a water column or between a power boiler and the shutoff valves required for the gauge glass what shall the minimum size be? (_____ mm) |
25mm |
|
At lower pressures, steam readily rises and _________ from the water. |
separates |
|
The intermittent blow-off line (is or is not) a drum internal. |
is not |
|
The continuous blowdown valve is usually a __________ valve with an indicator. |
regualting |
|
Some smaller boilers have a short pipe which discharges against a baffle in the steam drum. This pipe acts as an internal ___________ pipe. |
feed |
|
The chemical injection line is located near the __________ feed pipe. |
internal |
|
What purpose does the boiler steam drum serve?
a) provides a place for storage of steam b) provides a place for the distribution of feedwater c) provides a place in which equipment can be installed to remove impurities from the steam d) all of the above |
d) all of the above |
|
Relative to steam drum internals, a boiler water test is conducted to adjust or set the ___________ blow down valve (CBD) |
contiuous |
|
The steam drum in a modern watertube boiler is a complex piece of equipment with ________ mechanical stages to help separate steam from water. |
several |
|
The CBD pipe is controlled by a special __________ or metering valve. |
regulating |
|
Impurities must be removed from steam leaving the boiler because ___________ will form on turbine blades. |
deposits |
|
A boiler steam drum will allow load __________ to be accomplish more quickly. |
increases |
|
The component of a boiler which allows a space for the introduction of chemicals is the _________ drum. |
steam |
|
Some smaller boilers have a dry pipe in the steam section of the steam drum that acts as a __________. |
separator |
|
The chemical injection line is located near the __________ feed pipe. |
internal |
|
The continuous blow down collecting pipe is located a few inches ________ the water level in the steam drum. |
below |
|
The boiler continuous blowdown pipe is used to remove the greatest concentration of __________ solids from the drum. |
dissolved |
|
Water treatment chemicals are injected using an internal feed pipe near the __________ of the steam drum. |
bottom |
|
One of the purposes of combustion control is to: |
ensure the proper ratio of air and fuel |
|
If, during a flue gas analysis, the excess air to a boiler furnace is increased: |
CO2 with decrease |
|
Low fuel ________ in oil burners produces unsafe conditions of burning. |
pressure |
|
Due to various differences in the operation of the FBC plants, the following is required: |
A considerably different control system |
|
The efficiency of a combined cycle plant based on PFBC is about _____ higher than a conventional pulverized coal plant. |
5% |
|
One method of increasing combustion control at low operating rates in FBC units is to: |
Add more expensive control equipment |
|
Operating a PFBC furnace at low temperatures result in: |
Steam temperature limited over the period of heat supply |
|
Torsion bar safety valves are deigned for boilers that operate at greater than _______ kPa. |
8000 kPa |
|
If the bottom valve of a power boiler gauge glass is more than _____ m above the floor, the operating mechanism must indicate if the valve is open or closed. |
2.0 m (2.1m in moodle) |
|
The cyclone separator has ______ removed from the steam by centrifugal force. |
moisture |