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Questions and Answers
What happens if the feedwater regulator is stuck open?
What happens if the feedwater regulator is stuck open?
What is the purpose of a bowl at the bottom of the water column?
What is the purpose of a bowl at the bottom of the water column?
When checking a safety valve with the hand-lifting gear, the pressure should be no lower than ___% of the safety valve set pressure.
When checking a safety valve with the hand-lifting gear, the pressure should be no lower than ___% of the safety valve set pressure.
75
If valves are located between the boiler and water column, they must be:
If valves are located between the boiler and water column, they must be:
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When a hydrostatic test is put on a boiler, each safety valve should be:
When a hydrostatic test is put on a boiler, each safety valve should be:
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After installing a new gauge glass, the proper procedure for returning the glass to service is:
After installing a new gauge glass, the proper procedure for returning the glass to service is:
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The steam pressure gauge is graduated in:
The steam pressure gauge is graduated in:
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One of the purposes of the water column is to:
One of the purposes of the water column is to:
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The gauge glass should be blown down:
The gauge glass should be blown down:
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The flame failure control is tested by:
The flame failure control is tested by:
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Which of the following controls operates due to changes in temperature?
Which of the following controls operates due to changes in temperature?
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The pressure-sensitive device attached to the fan housing of a fully automatic burner starts operating when there is:
The pressure-sensitive device attached to the fan housing of a fully automatic burner starts operating when there is:
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If the pressuretrol starts the burner and ignition failed to take place, the control that protects the boiler is the:
If the pressuretrol starts the burner and ignition failed to take place, the control that protects the boiler is the:
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The pressure-sensitive device in Question 91 is sometimes called a(n):
The pressure-sensitive device in Question 91 is sometimes called a(n):
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Draft is measured in:
Draft is measured in:
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Which of the following is used to measure temperature?
Which of the following is used to measure temperature?
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The main stop valve is located on the:
The main stop valve is located on the:
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OS&Y stands for:
OS&Y stands for:
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An interlock control is a(n):
An interlock control is a(n):
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Trial for ignition refers to the:
Trial for ignition refers to the:
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More than one safety valve is required on boilers that have over:
More than one safety valve is required on boilers that have over:
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At 0 PSIG, how many BTU are necessary to change 1 lb of water at 212 degrees Fahrenheit into 1 lb of steam?
At 0 PSIG, how many BTU are necessary to change 1 lb of water at 212 degrees Fahrenheit into 1 lb of steam?
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Radiation is
Radiation is
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Steam at 100 PSI and 400 degrees Fahrenheit is
Steam at 100 PSI and 400 degrees Fahrenheit is
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Which of the following most closely defines sensible heat?
Which of the following most closely defines sensible heat?
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What is required to raise the temperature of 1 lb of water from 32 degrees to 212 degrees Fahrenheit?
What is required to raise the temperature of 1 lb of water from 32 degrees to 212 degrees Fahrenheit?
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Increasing the pressure has what effect on the boiling point of water?
Increasing the pressure has what effect on the boiling point of water?
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Heat absorbed by water when it changes from liquid to steam at the boiling point is called
Heat absorbed by water when it changes from liquid to steam at the boiling point is called
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Heat may be transferred in how many ways?
Heat may be transferred in how many ways?
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A boiler horsepower is defined as
A boiler horsepower is defined as
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A boiler's steam pressure gauge reads 150. What is the absolute pressure?
A boiler's steam pressure gauge reads 150. What is the absolute pressure?
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What does 212 degrees F equal on the Celsius scale?
What does 212 degrees F equal on the Celsius scale?
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One boiler horsepower is equal to how many Btu?
One boiler horsepower is equal to how many Btu?
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A British thermal unit is
A British thermal unit is
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Hydronic heat is
Hydronic heat is
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Superheated steam is
Superheated steam is
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2,545 Btu represents
2,545 Btu represents
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A throttling calorimeter is used to measure the quality of
A throttling calorimeter is used to measure the quality of
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The amount of heat in one pound of saturated steam is approximately equal to
The amount of heat in one pound of saturated steam is approximately equal to
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A boiler operating at 100 PSI has a dry saturated steam temperature of 338 degrees F. What is the boiler's water temperature?
A boiler operating at 100 PSI has a dry saturated steam temperature of 338 degrees F. What is the boiler's water temperature?
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A dry pipe is used to
A dry pipe is used to
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The purpose of a staybolt is to
The purpose of a staybolt is to
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The boiler vent valve is located on the
The boiler vent valve is located on the
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The purpose of the hole in the end of the staybolt is to
The purpose of the hole in the end of the staybolt is to
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A fusible plug melts at
A fusible plug melts at
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As the firing rate increases in a boiler equipped with a convection superheater, the steam temperature
As the firing rate increases in a boiler equipped with a convection superheater, the steam temperature
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When boilers are connected to a common header, it is required that an ample free blowing drain be provided between the stop valves if either or both boilers have
When boilers are connected to a common header, it is required that an ample free blowing drain be provided between the stop valves if either or both boilers have
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It is permissible to have only one bottom blowdown valve on a boiler when the
It is permissible to have only one bottom blowdown valve on a boiler when the
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When the boiler pressure exceeds ______ PSI, it is required that extra-heavy pipe be used on the blowoff system.
When the boiler pressure exceeds ______ PSI, it is required that extra-heavy pipe be used on the blowoff system.
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Baffles are placed between the tubes of a boiler for the purpose of
Baffles are placed between the tubes of a boiler for the purpose of
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A boiler has a steaming capacity of 35,500 lb of steam per hour. The evaporation rate is 10 lb/ft² of heating surface per hour. What is the horsepower rating of this boiler?
A boiler has a steaming capacity of 35,500 lb of steam per hour. The evaporation rate is 10 lb/ft² of heating surface per hour. What is the horsepower rating of this boiler?
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Boiler tube sizes are specified by
Boiler tube sizes are specified by
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The maximum size of boiler blowdown lines, valves, and fittings shall not exceed
The maximum size of boiler blowdown lines, valves, and fittings shall not exceed
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The purpose of an expansion tank in a hot water heating system is to provide for the expansion of
The purpose of an expansion tank in a hot water heating system is to provide for the expansion of
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Heavy accumulation of soot in a boiler will result in
Heavy accumulation of soot in a boiler will result in
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How are the tubes secured in a fire-tube boiler?
How are the tubes secured in a fire-tube boiler?
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A tube in a fire-tube boiler is surrounded by
A tube in a fire-tube boiler is surrounded by
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Atmospheric pressure is considered to be
Atmospheric pressure is considered to be
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In a water tube boiler,
In a water tube boiler,
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Diagonal stays are found in
Diagonal stays are found in
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Handholes and manholes are oval
Handholes and manholes are oval
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To check the water level in the gauge glass of a steam boiler
To check the water level in the gauge glass of a steam boiler
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The vent valve
The vent valve
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A high-pressure boiler has its safety valve set above
A high-pressure boiler has its safety valve set above
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Which of the following is an advantage of fire-tube boilers over water tube boilers?
Which of the following is an advantage of fire-tube boilers over water tube boilers?
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Water walls are found
Water walls are found
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The best time to bottom blow a boiler is at
The best time to bottom blow a boiler is at
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A telltale hole is found in a
A telltale hole is found in a
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A 2-inch boiler tube has a wall thickness of 3/16 inch. What is its inside diameter (ID)?
A 2-inch boiler tube has a wall thickness of 3/16 inch. What is its inside diameter (ID)?
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At what temperature does steel start to rapidly lose its strength?
At what temperature does steel start to rapidly lose its strength?
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A hot-water heating system is about to be started. How full of water should the expansion tank gauge glass be?
A hot-water heating system is about to be started. How full of water should the expansion tank gauge glass be?
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What is the relationship between longitudinal stress and circumferential stress?
What is the relationship between longitudinal stress and circumferential stress?
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A therm is equal to how many Btu?
A therm is equal to how many Btu?
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The factor of evaporation is
The factor of evaporation is
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The purpose of a bottom blowdown is to
The purpose of a bottom blowdown is to
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Damage by spalling refers to the
Damage by spalling refers to the
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Superheaters raise the temperature of
Superheaters raise the temperature of
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The steam space is
The steam space is
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The heating surface of a boiler is the area
The heating surface of a boiler is the area
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The purpose of a superheater is to
The purpose of a superheater is to
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What is the formula for the factor of evaporation?
What is the formula for the factor of evaporation?
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What can cause a superheater tube to overheat?
What can cause a superheater tube to overheat?
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A boiler has a steaming capacity of 34,500 lb of steam per hour. The evaporation rate is 10 lb/ft² of heating surface per hour. What is the boiler heating surface?
A boiler has a steaming capacity of 34,500 lb of steam per hour. The evaporation rate is 10 lb/ft² of heating surface per hour. What is the boiler heating surface?
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How many square feet of heating surface does a 3-inch fire-tube, 20 ft long with a 3/16-inch wall have?
How many square feet of heating surface does a 3-inch fire-tube, 20 ft long with a 3/16-inch wall have?
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In a high-temperature hot water boiler, what would cause a tube to overheat?
In a high-temperature hot water boiler, what would cause a tube to overheat?
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A downcomer is
A downcomer is
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Extreme firebox temperature changes cause
Extreme firebox temperature changes cause
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The low-water cutoff
The low-water cutoff
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Steam coming from the bottom try cock would indicate
Steam coming from the bottom try cock would indicate
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What type of valve has the most resistance to flow?
What type of valve has the most resistance to flow?
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When checking the water level of a boiler,
When checking the water level of a boiler,
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A siphon or pigtail is used to protect a steam pressure gauge
A siphon or pigtail is used to protect a steam pressure gauge
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The feedwater regulator is located
The feedwater regulator is located
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An automatic feedwater regulator
An automatic feedwater regulator
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To test the low-water cutoff,
To test the low-water cutoff,
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The purpose of testing a safety valve by hand is to
The purpose of testing a safety valve by hand is to
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The automatic control that protects a boiler from being dry fired is the
The automatic control that protects a boiler from being dry fired is the
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To check the water level in the gauge glass of a steam boiler,
To check the water level in the gauge glass of a steam boiler,
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On a steam boiler, testing the operation of the safety valve by hand with the boiler under pressure should be done
On a steam boiler, testing the operation of the safety valve by hand with the boiler under pressure should be done
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What type of valve has the least resistance to flow?
What type of valve has the least resistance to flow?
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Study Notes
Boiler Basics
- At 0 PSIG, it takes 970 BTU to convert 1 lb of water at 212°F into steam.
- Radiation transfers heat via waves, differing from conduction (direct contact) and convection (movement of liquids/gases).
- Superheated steam is identified at 100 PSI and 400°F, indicating heat beyond saturation.
Heat and Energy
- Sensible heat is measurable and can be felt by a thermometer.
- To heat 1 lb of water from 32°F to 212°F, 180 BTU is required.
- Raising water's boiling point requires increased pressure; the temperature will rise.
Heat Transfer Terms
- Latent heat refers to heat absorbed during the phase change from liquid to steam.
- Heat can be transferred in three ways: conduction, convection, and radiation.
Boiler Operations
- Boiler horsepower equates to the evaporation of 34.5 lb of water at 212°F per hour.
- The absolute pressure from a 150 PSIG reading is 164.7 PSIA (adding atmospheric pressure).
Measurement Conversions
- 212°F equals 100°C; one boiler horsepower equals 33,472 BTU.
- A British thermal unit (BTU) raises 1 lb of water by 1°F.
- A therm is an energy measurement equal to 100,000 BTU.
Boiler Components and Calculations
- Hydronic heat utilizes hot water; superheated steam is reheated steam.
- A throttling calorimeter measures the quality of saturated steam.
- Approximate heat in 1 lb of saturated steam is 1,150 BTU.
- A boiler's heating surface area can be calculated based on evaporation rates and steam capacity.
Safety and Maintenance
- Fusible plugs melt at 450°F, providing a safety mechanism to prevent overheating.
- Boiler vent valves are located on the top of the steam drum to release excess pressure.
- A dry pipe separates moisture from steam as it exits the boiler drum.
Structural Elements
- Staybolts strengthen fire-tube boilers by supporting flat plates.
- Baffles direct flue gas travel and improve efficiency.
- A high-pressure boiler's safety valve operates above 15 PSI.
Operating Conditions
- Bottom blowdown removes sludge; testing low-water cutoff ensures safe operation.
- Gauge glass indicates the water level; issues could arise from blocked connections.
Valve Operations
- Globe valves provide high resistance to flow, while gate valves offer the least resistance.
- Siphon protects steam pressure gauges from high-temperature steam.
Testing and Regulation
- Monthly testing of safety valves under pressure confirms they can lift correctly.
- Automatic feedwater regulators maintain proper water levels in the boiler system.
Troubleshooting
- Low-water level indications are checked by try cocks on the boiler.
- Issues with boiler efficiency can stem from soot accumulation or inadequate maintenance.
Safety Features
- The automatic control that prevents dry firing in boilers is the low-water cutoff.
- Steam temperature rapidly decreases boiler efficiency if not managed properly due to spalling.
Additional Information
- Diagonal stays are typically found in fire-tube boilers, contributing to structural integrity.
- The heating surface must be exposed to flame to maximize efficiency in boiler operation.### Valves and Safety Measures
- Safety valves must be locked or sealed open if located between the boiler and water column.
- During hydrostatic testing, safety valves should be held to their seat by a testing clamp.
Gauge Glass Procedures
- After installing a new gauge glass, open the drain and crack open the top valve for proper service return.
- The gauge glass should be blown down daily to ensure accuracy and safety.
Pressure Gauges and Measurements
- Steam pressure gauges are typically graduated in pounds per square inch (PSI).
- Draft is measured in inches of water, which indicates airflow in system applications.
Monitoring and Control Devices
- One purpose of a water column is to dampen the oscillation of water in the gauge glass, providing stable readings.
- An Aquastat operates based on temperature changes, ensuring boiler function within safe limits.
- Vaporstats are pressure-sensitive devices that indicate fan failure, triggering protective measures.
Ignition and Flame Failure Controls
- The flame failure cutoff protects the boiler if ignition fails after burner activation.
- Trial for ignition involves the flame scanner detecting the pilot flame, ensuring a safe ignition process.
Boiler Surface Area Regulations
- A boiler must have more than one safety valve if it has over 500 ft² of heating surface to meet safety standards.
Measurement Tools and Their Functions
- A pyrometer is used to measure temperature accurately, critical for maintaining proper operating conditions.
- OS&Y stands for "outside screw and yoke," a type of valve used for controlling steam flow.
Safety and Interlock Systems
- Interlock controls are devices preventing firing attempts unless deemed safe, enhancing operational safety.
- The main stop valve is located on the steam line, crucial for regulating flow in the system.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge with this flashcard quiz designed for the MA 2nd Class Fireman's exam. The quiz covers essential topics such as heat transfer and energy requirements, providing an excellent review for aspiring firemen. Enhance your understanding and preparation effectively.
