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70 Cards in this Set
- Front
- Back
A furnace wall soot blower sequence of operation is extend, __________ and blow, retract. |
rotate |
|
Soot blowers are especially required on a boiler fired with ____________ coal. |
pulverized |
|
During a soot blowing operation the boiler firing rate should be at least _____% |
50% |
|
Shot cleaning pellets have a diameter of approximately _____ mm. |
6.0mm |
|
Soot and ash are undesirable on tube surfaces because they reduce boiler ____________. |
efficiency |
|
As it relates to soot blower operations, shooting condensate or wet steam at the tube surfaces may cause quick __________. |
erosion |
|
In addition to reducing heat transfer, soot and ash on fireside tubes also __________ draft fan power. |
increases |
|
Iron shot or pellets, fall by __________ onto the surfaces of the tubes and ricochet from one tube to another. |
gravity |
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A stationary soot blower has a row of __________ throughout the lance length. |
nozzles |
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A long retractable soot blower will blow during extension and retraction as it __________. |
rotates |
|
If soot accumulation is not dealt with, over time the accumulation may restrict the ________ gas passage. |
flue |
|
Soot and ash are undesirable on tube surfaces because they reduce ___________ efficiency. |
boiler |
|
Most of the ash removed by the shot is removed in the ________ gas stream. |
flue |
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The steam used for soot blowing is preferably __________ at the sootblower nozzle. |
superheated |
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While a steam soot blower is in operation it is cooled by __________. |
steam |
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A steam boiler is blown down in order to __________ sediment and scale forming matter from the boiler. |
discharge |
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A "rule of thumb" rate of continuous blowdown is approximately ___% of steaming rate. |
1% |
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Boiler water having the greatest concentration of suspended solids is found in the bottom of the _______ drum. |
mud |
|
The CSA B51 Code requires the installation of a blow-off tank for all boilers operating at or above ______ kPa. |
103 kPa |
|
The water temperature at the blow-off tank outlet may not exceed ____˚C. |
65˚C |
|
The type of blowdown system used on a boiler is usually a function of the type of __________ water treatment used. |
external |
|
Blowdown guidelines can be found in ASME Section _____. |
VII |
|
Boiler water having the greatest concentration of suspended solids is found in the bottom of the _______ drum. |
mud |
|
Water leaving a blowdown tank and entering a sewer must not exceed _____˚C. |
65˚C |
|
According to CSA B-51, all boilers discharging into a sewer and operating above what pressure require a blow-off tank? ( ____ kPa) |
103 kPa |
|
A blowdown tank will lower the temperature and __________ of the incoming boiler water. |
pressure |
|
When two seatless valves (slow opening) are used for intermittent blowdown, the operation sequence is:
Open the downstream valve _______ and close it _______. |
first, last |
|
Intermittent blowdown systems:
• are subject to rapid ____________ changes • flow through the piping only for a short period of time • two seatless blowdown valves may be fitted • if the boiler is operating above 103 kPa, a blow-off tank is required |
temperature |
|
The preferred arrangement of valves on a boiler blow-off line is a quick-opening valve ________ to the boiler followed by a slow-openig valve. |
closest |
|
The external inspection of a boiler includes making sure the __________ are in good operating condition. |
valves |
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If a new boiler is not properly boiled out, it may result in a __________ condition occurring. |
foaming |
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Superheater vents are usually opened before firing a boiler to prevent _____________ of the superheater. |
overheating |
|
If three boilers each have a pressure of 130 kPa, the pressure in the steam header will be _______ kPa. |
130 kPa |
|
When cooling down a steam boiler that has been taken out of service, a vent valve on the steam drum should be opened to prevent a __________ from occurring. |
vacuum |
|
Boiling out of boilers is done with a ____________ solution. |
alkaline |
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A boiler furnace ___________ must last a specific amount of time. |
pre-purge |
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If a new boiler is not properly boiled out, it may result in a ____________ condition occurring. |
foaming |
|
Steam headers must be warmed up properly to avoid __________ stress. |
thermal |
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While a boiler is warming up it is good practice to check the _______ water fuel cut-off device for proper operation. |
low |
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A boiler inspection must be done _________ closing up and filling the boiler. |
before |
|
When igniting a gas or oil fired boiler you should ignite from an __________ igniter. |
electric |
|
A boiler warm-up should be done _________ to minimize any differential expansion. |
slowly |
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Boiler dry-out means to dry out the new ____________. |
refractory |
|
Before removing a boiler from service for maintenance purposes it is beneficial to ___________ the boiler. |
blowdown |
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New refractory must be thoroughly and properly cured with a light fire because it contains moisture which can cause it to ___________ if not cured. |
fracture |
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A boiler has been in operation for one year and is now taken off the line for cleaning, repair and inspection. The boiler is one of three in a battery and the other two will remain in operation. This one boiler is to be drained and cooled. Before any person is allowed to enter the boiler drum, the correct safety procedure requires that the main steam, blowdown and feed water valves be _________, chained, tagged, and ___________. |
closed, locked |
|
Before lighting up a boiler you should: (choose all that apply)
a) purge the furnace b) open the blow down valve c) check the fuel supply d) fill the boiler with water |
a) purge the furnace c) check the fuel supply d) fill the boiler with water |
|
When you first notice that the water level in the boiler gauge glass can no longer be seen, it is best first to ensure that the boiler is not _______ filled. |
over |
|
The principle cause of furnace explosions is when the _________ cycle before lighting is not long enough or doesn't occur. |
purge |
|
A pressure explosion of a boiler may occur if _____ boiler water level produces weakening of tubes. |
low |
|
Control systems should be checked and maintained ___________, this is the best way to prevent an accident on a boiler with automatic controls. |
regularly |
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The best method to provide a continuous record for boiler operation, maintenance, and testing is to use an official plant log book on a ________ basis. |
dialy |
|
Operating soot blowers below fifty percent of full load may cause __________- out. |
flame |
|
A reason for many boiler accidents may be due to Inadequate ____________ of operating personnel. |
training |
|
Insufficient ________ is the main cause of furnace explosion. |
purge |
|
Poor combustion due to the insufficient amount of ________ may cause a furnace explosion. |
air |
|
The best method of ensuring adequate attention is being given to the boiler and its controlling and safety devices is to maintain a _____________ showing testing results and by whom they were done. |
log-book |
|
A dark coloured smoke coming from the stack may be an indication of a dirty ___________ in an oil fired burner. |
nozzle |
|
When preforming a soot blowing operation it is important to maintain ________ stability. |
flame |
|
A boiler pressure or waterside explosion may be cause by a _______ water condition. |
low |
|
One cause of flame failure in oil or gas fired boilers is _______ in the fuel. |
water |
|
In the event of a flame failure, an automatic boiler will close the _________ valve. |
fuel |
|
When two seatless valves are used for intermittent blowdown, the operation sequence is: |
open downstream first and close last |
|
Dissolved solids in a boiler can cause: |
foaming and carry-over |
|
The continuous blowdown is used in addition to the: |
main blowdown |
|
Natural gas fired power boiler flames should be fairly rapid, mostly ______, and some _________. (colours) |
blue; orange |
|
In the event of a low water condition in a boiler the engineer in charge should: |
shut down burner; let cool; inspect |
|
if the safety valve on a boiler pops and the only pressure gauge indicates well below pop pressure, you could: |
reduce boiler pressure and get the gauge checked |
|
A natural gas power boiler flame should be: |
fairly rapid, mostly blue, and some orange |
|
If a burner fails, this could cause admission of unburned fuel to the furnace which may ________. |
explode |