Chapter 9-12 Flashcards
- All new boilers, and boilers which have been repaired on their pressure parts, require a _____ to be performed upon them.
A) acidifying B) descaling C) hydrostatic test D) refractory dry out E) soot blowing
C) hydrostatic test
- On small boilers, a hydrostatic test is done with:
A) compressed nitrogen B) water pressure C) steam pressure D) compressed air E) acetic acid
B) water pressure
- When a hydrostatic test is done on a boiler, the pressure shall be under control at all times, so that the required test pressure is never exceeded by more than:
A) 0.1 B) 0.06 C) 0.05 D) 0.04 E) 0
C) 0.05
- All traces of oil or grease must be removed from a boiler by boiling out with:
A) a suitable acid B) hot water C) a suitable alkali D) a suitable solvent E) sodium sulphite and hydrazine
C) a suitable alkali
- After construction of the boiler setting, the refractories will contain a considerable amount moisture. Referring to this situation, which of the following statements are correct?
1) the refractories should be dried out as fast as possible
2) the refractories should be dried slowly
3) if the refractories are dried too slowly, large cracks will appear
4) if the refractories are dried too quickly, the refractories will crack
A) 1,3 B) 2,4 C) 1 D) 2 E) 3
B) 2,4
- An alkaline boilout is used on a boiler:
A) when the boiler has had oil contamination
B) before overhauls
C) after an acid clean
D) before returning the boiler to service after an overhaul
E) after an acid clean
A) when the boiler has had oil contamination
- _____ storage is preferable for boilers that are out of service for an extended period of time or in locations where freezing temperatures.
A) dry
B) short
C) wet
D) long
A) dry
- Moisture absorbing materials should be placed on trays inside the drums to absorb moisture from the _____.
A) metal
B) tubes
C) air
D) fuel
C) air
- Inert gas, such as nitrogen, is connected to the drum vent to maintain approximately _____ kPa. Positive pressure.
A) 100
B) 35
C) 325
D) 500
B) 35
- Wet storage is used if the standby boiler may be required for service at _____ notice.
A) dry
B) short
C) wet
D) long
B) short
- Oxen scavengers are added to water to increase the _____ and to absorb any oxygen present in the feedwater.
A) pH
B) solids
C) alkalinity
D) conductivity
C) alkalinity
- The _____ valve on the shut down boiler will close when the Boiler pressure drops below the header pressure.
A) fuel
B) feedwater
C) header
D) non return
D) non return
- When the pressure in the boiler steam drum drops to _____ kPa, the drum vents are to be opened to avoid the formation of a vacuum within the boiler.
A) 170
B) 500
C) 5
D) 1000
A) 170
- The fireside of the boiler is cleaned of all dust and soot by washing with a hot _____ solution of water.
A) acidic
B) alkaline
C) caustic
D) soapy
B) alkaline
- The waterside of the boiler is not washed until the _____ has examined and determined the amount of sludge and scale present.
A) manager
B) worker
C) inspector
D) owner
C) inspector
- During the high pressure flush, the blowdown valves should be disconnected, if possible, to prevent them fro getting plugged with _____.
A) water
B) rust
C) dirt
D) scale
D) scale
- When examining waterside surfaces, the inspector looks for signs of corrosion, pitting, and _____ of the metal.
A) bulging
B) blisters
C) cracking
D) wearing
C) cracking
- _____ is the result of dissolved oil or oxygen in the feedwater.
A) scale
B) pitting
C) cracking
D) bulging
B) pitting
- When inspecting the fireside of the boiler, the tube and drum surfaces are examined for bulges or blisters, which indicate _____.
A) drying
B) drafting
C) overheating
D) underheating
C) overheating
- Refractory and brickwork of the burners, baffles, and furnace walls are checked for _____.
A) cracks
B) discoloring
C) melting
D) deterioration
D) deterioration
- The dampers and air registers ar checked for _____ and to ensure they move freely.
A) holes
B) dust
C) warpage
D) design
C) warpage
- When performing an internal inspection of a boiler, examine the waterside through all the handhole doors for:
A) tube pitting B) carbon deposits C) moisture D) process contamination E) small salt traces
A) tube pitting
- After an acid clean on a boiler, the boiler is flushed with an alkaline solution such as:
A) lime B) citrus C) molybdenum D) soda ash E) caustic soda
D) soda ash
- Internal boiler cleaning is usually preceded by:
A) a hydrostatic test B) an internal inspection C) an external inspection D) an overhaul E) retubing
B) an internal inspection
- The frequency of internal boiler cleaning depends on:
1) feedwater quality
2) operating schedule
3) operating condition
4) water treatment control
A) 1,2,3 B) 1,3,4 C) 2,3,4 D) 1,2,3,4 E) 1,2,4
D) 1,2,3,4
- When mechanically cleaning a boiler, the boiler must be:
A) at full load B) at half load C) at minimum load D) off the line E) at 60% load
D) off the line
- _____ is carried out to remove scale that has been allowed to build up on the waterside of boilers.
A) soot blowing B) swaging C) pressure rolling D) acidizing E) expanding
D) acidizing
- The main concern of the _____ _____ is to operate the boiler safely and efficiently.
A) power engineer
B) maintenance manager
C) boiler inspector
D) plant manager
A) power engineer
- Heating surfaces must be _____ to ensure maximum heat transfer to the water and steam in the boiler.
A) large
B) clean
C) contacted
D) free
B) clean
- In order for the gauge glass to show the correct level, all connections to the gauge glass and the water column must be_____ to ensure they are clear and free from obstructions.
A) tight
B) purged
C) blown down
D) unblocked
C) blown down
- If the water column is fitted with high and low water alarms, then their operation is checked at regular intervals.
A) true
B) false
A) true
- The boiler operators must be familiar with the _____ for starting up the standby feed pump and stopping the in service pump.
A) procedure
B) schedule
C) boiler
D) deaerator
A) procedure
- In order to avoid scale formation and corrosion in the _____, the make up water for the feedwater supply must be properly treated.
A) deaerator
B) boiler
C) furnace
D) tank
B) boiler
- The operator must be familiar with manual operation of the _____ system, in case of a system failure.
A) generator
B) water
C) control
D) air
C) control
- All boilers should be bottom blown, at least once a day. This is done to remove _____ that has accumulated in the bottom drum.
A) scale
B) water
C) alkalinity
D) sludge
D) sludge
- The operator should make a general inspection of the entire plant every _____ hours.
A) two
B) three
C) four
D) six
A) two
- Furnace explosions occur when an accumulation of combustible gases ignite and explode within the furnace, or gas passes of the boiler.
A) true
B) false
A) true
- _____ explosions occur when a pressure part of the boiler, such as the steam drum, fails due to steam pressure, or a structural weakening of the metal.
A) furnace
B) pressure
C) gas
D) water
B) pressure
- List five of the most common causes of furnace explosions:
1) failure to purge the furnace adequately before startup
2) admission of fuel to main burner before pilot flame or other ignition source is established
3) loss of ID fan
4) the main flame in the furnace may get blown out
5) loss of FD fan
6) attempting to light one burner off other burners in operation
7) incorrect amount of air supplied to the burner, resulting in incomplete combustion
A) 3,4,5,6,7 B) 1,2,3,6,7 C) 1,2,3,4,5 D) 1,2,4,6,7 E) 1,3,4,6,7
D) 1,2,4,6,7
- List the two major causes of pressure explosions:
1) pressure in excess of that for which he Boiler was designed
2) poor quality feedwater
3) weakening of the material to an extant that the pressure part fails
4) poor fuel quality
5) non specification boiler materials
A) 1,5 B) 1,3 C) 1,2 D) 1,4 E) 3,5
B) 1,3
- Furnace explosions are caused by:
1) failing to supply sufficient air to the furnace when boiler is lit
2) failing to purge furnace properly
3) relighting burners off hot refractory
4) maintaining efficient igniters and pilots
5) installing flame sensing devices
A) 1,2,3 B) 2,3,4 C) 3,4,5 D) 1,2,5 E) 1,4,5
A) 1,2,3
- Which of the following boilers would most likely have soot blowers?
1) gas fired boilers
2) electric boilers
3) coal fired boilers
4) oil fired boilers
A) 1,2 B) 3,4 C) 1,3,4 D) 1,2,3,4 E) 1,2,4
B) 3,4
- During the operation of a boiler, the heating surfaces exposed to the combustion gases tend to become coated with soot and ash, which:
1) lowers the steam pressure in the boiler
2) acts as an insulation and reduces heat transfer
3) lowers the efficiency and capacity of the boiler
4) increases the draft power required
A) 1,2,3,4 B) 1,2,3 C) 1,3,4 D) 1,2,4 E) 2,3,4
E) 2,3,4
- The method most commonly used to remove soot and ash from boiler heating surfaces is to blast away these deposits by means of:
1) a natural gas jet
2) a steam jet
3) a water jet
4) an air jet
A) 1,3 B) 1,2 C) 2,3 D) 2,4 E) 3,4
D) 2,4
- Soot blowers can be classified as:
1) manual operation
2) automatic operation
3) stationary operation
4) movable operation
A) 1,2,3,4 B) 1,2 C) 3,4 D) 1,2,4 E) 1,3,4
A) 1,2,3,4
- Stationary type soot blowers are located in the:
1) secondary superheater section
2) air heater section
3) economizer section
4) furnace walls
A) 2,3 B) 1,2 C) 2,4 D) 1,3 E) 3,4
A) 2,3
- The reason for having retractable soot blowers is because they:
1) are cheaper than stationary soot blowers
2) are used in the high temperature zones of the boiler
3) use different cleaning mediums than stationary types
4) they are protected from high temperatures when withdrawn from the boiler
A) 1,2,3,4 B) 1,2 C) 3,4 D) 2,4 E) 1,2,3
D) 2,4
- Which of the following procedures are correct during soot blowing periods?
1) the firing should be switched from coal to gas
2) the boiler should be firing at least 30% rate
3) the boiler should be firing at least 70% rate
4) the furnace pressure should be below atmospheric pressure
A) 1,2,4 B) 1,3,4 C) 2,4 D) 3,4 E) 1,2,3
C) 2,4
- It is important that soot blowers be adjusted so that they do not impinge directly upon tubes or baffles because:
A) they cause too much smoke coming out the smoke stack
B) erosion of these parts will take place
C) it is hard on the soot blowers due to too much back pressure
D) they would not clean the surface very well in this position
E) the soot blower nozzles will plug up
B) erosion of these parts will take place
- Which of the following conditions would indicate that the soot blowers should be operated:
1) the steam pressure is low in the boiler drum
2) high draft loss through the boiler
3) uneconomical steam temperature
4) uneconomical gas temperature
A) 1,2,3,4 B) 1,2,3 C) 1,3,4 D) 2,3,4 E) 1,2,4
D) 2,3,4
- Which of the following is caused from scale buildup on boiler tubes:
1) increased boiler efficiency
2) weakening of tube metal
3) decreased boiler efficiency
4) increased flue gas temperature
5) cracks in boiler tubes
A) 1,2,3,4 B) 1,3,4,5 C) 2,3,4,5 D) 1,2,4,5 E) 1,2,3,5
C) 2,3,4,5
- When adding phosphate to the boiler water, the chemical may:
1) combine with dissolved solids in the boiler water
2) decrease the dissolved solids in the boiler water
3) increase the suspended solids in the boiler water
4) increase the pH of the boiler water
A) 1,2,3 B) 1,2,4 C) 1,3,4 D) 2,3,4 E) 1,2,3,4
C) 1,3,4
- Chelating agents feed to the boiler water:
1) require close control to prevent corrosion
2) reduce scale buildup within high pressure boilers
3) protects against corrosion within the boiler
4) obtains best results with soft water
A) 1,2,3 B) 1,3,4 C) 1,2,4 D) 2,3,4 E) 1,2,3,4
B) 1,3,4
- Organics, such as tannins, lignins, and starches are used to:
1) control silica in boiler water
2) reduce corrosion within the boiler
3) coat suspended solids in the boiler water
4) produce a nonsticky sludge in the boiler water
A) 1,2,3 B) 1,3,4 C) 1,2,4 D) 2,3,4 E) 1,2,3,4
B) 1,3,4
- To reduce scale and mud formation within the boiler, we:
1) force the hardness in the water to come out of solution by feeding sulphite to the boiler water
2) treat the suspended solids in the boiler water with lignins
3) remove suspended solids from the boiler water through blow off
4) feed soda ash, caustic soda, or sodium phosphate to precipitate solids in boiler water
A) 1,2,3 B) 1,2,4 C) 1,3,4 D) 2,3,4 E) 1,2,3,4
D) 2,3,4
- Certain chemicals introduced into the boiler water to prevent scale may:
1) form a mud or sludge
2) cause foaming or priming
3) result in corrosion attack on the metal
4) result in reduced boiler blow off
A) 1,2,3 B) 1,3,4 C) 1,2,4 D) 2,3,4 E) 1,2,3,4
A) 1,2,3
- Carbon dioxide dissolved in boiler feed water causes:
1) a reduced pH value in the water
2) metal loss in the condensate piping
3) an increase in the water alkalinity
4) damage to the feed pump
A) 1,2,3 B) 1,2,4 C) 1,3,4 D) 2,3,4 E) 1,2,3,4
B) 1,2,4
- Water which has been mechanically aerated:
A) is suitable to feed directly to the boiler without further treatment B) will be low in dissolved oxygen C) will be free of dissolved gases D) may cause pitting in the boiler metal E) will be high in dissolved CO2
D) may cause pitting in the boiler metal
- Contributors to corrosion within a steam boiler are:
1) oxygen
2) carbon dioxide
3) a low pH
4) high chelate concentrations
A) 1,2,3 B) 2,3,4 C) 1,3,4 D) 1,2,4 E) 1,2,3,4
E) 1,2,3,4
- An amine, which is fed to the boiler for protection of the condensate return lines against corrosion, may:
1) raise the pH of the condensate
2) coat the surfaces of the return piping
3) neutralize the acid in the condensate
4) cause the condensate to become acidic
A) 1,2,3 B) 1,2,4 C) 1,3,4 D) 2,3,4 E) 1,2,3,4
A) 1,2,3
- Hydrazine is used in some high pressure boilers:
A) to control the dissolved solids B) to prevent foaming C) to eliminate erosion D) to reduce oxygen pitting E) to condition the sludge
D) to reduce oxygen pitting
- In some boilers, caustic soda (sodium hydroxide) is injected into the boiler water. As a result:
1) the pH of the boiler water is increased
2) foaming could occur at high concentration
3) caustic embrittlement could occur
4) boiler water acidity is increased
A) 1,2,3 B) 1,3,4 C) 1,2,4 D) 2,3,4 E) 1,2,3,4
A) 1,2,3
- Factors required to produce caustic embrittlement are:
1) a high pH in the boiler water
2) stress of the Boiler pressure parts
3) a riveted joint in the boiler
4) a leak of boiler water
A) 1,2,3 B) 2,3,4 C) 1,3,4 D) 1,2,4 E) 1,2,3,4
D) 1,2,4
- The most undesirable feature of impurities in boiler feedwater is:
A) scale B) caustic embrittlement C) corrosion D) carry over E) sludge
C) corrosion
- Corrosion of metal in a boiler system is caused by:
1) a low pH of the boiler water
2) oxygen being absorbed by the boiler water
3) maintaining an OH- ions concentration higher than that of the H+ ions in the boiler water
4) carbon dioxide being allowed into the return condensate
A) 1,2,3 B) 1,2,4 C) 1,3,4 D) 2,3,4 E) 1,2,3,4
B) 1,2,4
- Failure to filter surface water before using it in a boiler may result in:
1) a hard, tight scale firming on the water surfaces of the boiler metal
2) foaming within the boiler
3) a sludge collecting in the drums
4) boiler water carry over with the steam
A) 1,2,3 B) 1,3,4 C) 1,2,4 D) 2,3,4 E) 1,2,3,4
D) 2,3,4
- Boiler blow off is an important factor in feedwater control because it:
1) should be completed before the boiler water is tested
2) allows removal of sludge thus assists in the prevention of scale
3) increases scale formation
4) should be completed afte the boiler water is tested
5) will help control dissolved solids within the boiler
A) 2,4,5 B) 3,4,5 C) 2,3,5 D) 1,2,3 E) 2,3,4,5
A) 2,4,5
- The prime purpose of a continuous blow off line from the steam drum of a watertube boiler is to:
A) heat the make up water supplying a deaerator
B) reduce the solids level of the oiler water by intermittent operation of the blow off valves
C) control the dissolved oxygen in the boiler water
D) control the quantity of scale forming salts within the boiler water
E) reduce the water level in the boiler
D) control the quantity of scale forming salts within the boiler water
- _____ is any solid, liquid, or vaporous contaminants that leaves the boiler with he steam.
A) carryover
B) blowdown
C) feedwater
D) mist
A) carryover
- _____ is particularly harmful as it forms a very hard deposit on turbine blades.
A) carryover
B) mist
C) silica
D) phosphate
C) silica
- The causes of carryover can be divided into two broad categories, namely, mechanical and _____,
A) virtual
B) carryover
C) upset
D) chemical
D) chemical
- Chemical carryover is primarily caused by _____.
A) foaming
B) misting
C) water
D) load
A) foaming
- Mechanical carryover can be prevented by careful boiler design and by operating the boiler within the design parameters for _____ level and firing rates.
A) chemical
B) water
C) blowdown
D) impurities
B) water
- Chemical carryover can be prevented by chemical injection, mud drum blowdown, and _____ _____.
A) pure water
B) boiler load
C) continuous blowdown
D) more chemicals
C) continuous blowdown
- Efficient control of boiler blowdown is an important objective in the operation of most boilers.
A) true
B) false
A) true
- A simple blowdown system involves control that is totally reliant on the _____.
A) effluent
B) chemicals
C) conductivity
D) operator
D) operator
- Control of the continuous blowdown flow is _____ adjusted by the operator.
A) manually
B) automatically
C) quickly
D) slowly
A) manually
- Erratic solids levels in the boiler result in erratic residuals of phosphate, sulphite, and so on, which leads to confusion over the amounts of chemicals that are added.
A) true
B) false
A) true
- A significant improvement in _____ can be accomplished by recovering heat from the blowdown water and from its flash steam.
A) control
B) efficiency
C) recovery
D) chemical
B) efficiency
- The phenolphthalein alkalinity test is carried out on boiler water:
1) to indicate the amount of bicarbonate sin the boiler water
2) to indicate the amount of dissolved hydroxides in the boiler water
3) to determine the “P” alkalinity value of the boiler water
4) to indicate the amount of carbonates in the boiler water
A) 1,3,4 B) 1,2,4 C) 1,2,3 D) 2,3,4 E) 1,2,3,4
D) 2,3,4
- To determine the amounts of all the dissolved materials, which cause alkalinity of the water, you should:
A) complete a pH test B) complete a methyl orange test C) complete a phosphate test D) complete a phenolphthalein alkalinity test E) complete a conductivity test
B) complete a methyl orange test
- An accurate pH reading of boiler water may be obtained by:
A) using litmus paper in the water sample
B) measuring the hydrogen ion concentration in the water sample
C) the total alkalinity test
D) completing the hardness test
E) completing a phosphate test
B) measuring the hydrogen ion concentration in the water sample
- The test used to determine the ppm of phosphate in the boiler water:
A) has a sample with an end colour of blue
B) requires the addition of potassium-iodide-iodate solution be added to the sample
C) uses an indicator which causes the water sample to turn yellow at the end point of the test
D) requires sulphuric acid be titrated into the sample until a faint pink colour develops
E) requires the addition of a methyl orange indicator
A) has a sample with an end colour of blue
- The sodium sulphite test on boiler water:
A) requires an amount of starch be added to the sample
B) should be filtered prior to adding test chemicals
C) should produce an end reading of 20 ppm or less
D) indicates the acidity of the boiler water
E) the total dissolved solids in the boiler water measures
A) requires an amount of starch be added to the sample
- When testing boiler water for dissolved solids:
A) we measure the amount of electrical current the sample will conduct
B) we must neutralize the oxide ion first
C) phenolphthalein is added to the sample to cause a blue colour to appear, neutralizing the water
D) filter the sample, then add sulphuric acid to neutralize the water
E) measure the “m” and “P” alkalinities
A) we measure the amount of electrical current the sample will conduct
- When using a meter to determine the pH of boiler water:
A) the dissolved salts in the sample should first be neutralized
B) the voltage between the electrodes will vary according to the hydrogen iron concentration of the sample
C) the hydrogen ion concentration generates a current in the solution, which is measured and read in pH numbers
D) the voltage between the electrodes will vary inversely to the concentration of hydrogen ions
E) the voltage between the electrodes is not effected by the concentration of hydrogen ions
B) the voltage between the electrodes will vary according to the hydrogen ion concentration of the sample
- Shot feeding involves the injection of chemicals over a relatively _____ period of time.
A) long
B) intermittent
C) short
D) measured
C) short
- A _____ feed system. This involves feeding the chemicals to the boiler system at the most efficient isn’t injection points and at a steady and continuous rate.
A) closed bypass
B) shot
C) slug
D) continuous
D) continuous
