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The Big 109
All of the 109 Questions potentially on any 2nd Class Firemans Exam. Finished! Good Luck Everyone!
109
Engineering
08/11/2009

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Term
What can you do with a Second Class Fireman's License?
Definition
With a Second Class Fireman's License one can operate any boiler or boilers under the engineer of fireman in direct charge there of.
Term
What is the D.P.S.'s definition of a boiler? A pressure vessel?
Definition
A boiler is a closed vessel in which water, under pressure, is transformed into steam by the application of heat. A Pressure Vessel is a closed vessel in which the source of pressure is external to itself. Any pressure vessel not defined as a boiler.
Term
How often must high pressure boilers be inspected in Massachusetts?
Definition
A high pressure boiler must be inspected once each year. The inspections must be internal and external. the external must be performed with the boiler under pressure and the internal with the boiler offline.
Term
What information is on a Certificate of Inspection?
Definition
Name or Owner/User, Location, Size and number of boiler, date of Inspection, Signature of Inspector, M.A.W.P.
Term
How often must air tanks be inspected?
Definition
Compressed air tanks, unless otherwise exempt, over 50PSI must be inspected every two years.
Term
How often must refrigeration equipment be inspected?
Definition
All refrigeration and air conditioning equipment requiring a certificate from the D.P.S. must be inspected at least once a year.
Term
What is a ton of refrigeration?
Definition
The melting of one ton of ice in a 24 hour period. (or 2,000 times the latent heat of fusion which is 144 is 288,000 BTU's per day or 12,00 BTU's/HR)
Term
How does the D.P.S. determine Boiler Horsepower?
Definition
(A.) Manufacturers tag (B.) Steam Output divided by 34.5 (C.) Input BTU's/HR divided by 41,840 (D.) Output BTU's/HR divided by 33475.
Term
How does the D.P.S. determine Turbine Horsepower?
Definition
By the outside diameter of the steam supply line. Does not exceed 1.75 inches less than 9HP. Over 1.75 and does not exceed 3.5 inches = 50HP which is a third class plant. Over 3.5 inches but not greater than 5 inches = 150HP which is a second class plant. Over 5 inches = 150HP which is a first class plant.
Term
Who can appeal the results of an examination by the D.P.S.?
Definition
A person who feels aggrieved by the action of an inspector or inspectors has the right to appeal.
Term
Which boilers require only Periodic Attendance?
Definition
Boilers that have between 9 ans 250 Boiler Horsepower require periodic attendance.
Term
What Boilers Require only Non-Continuous attendance?
Definition
boilers between 251 and 500 Boiler horsepower only Require Non-Continuous attendance.
Term
What boilers require Continuous Attendance?
Definition
Boilers over 501 Boiler Horsepower require continuous attendance.
Term
What is the difference between a gate valve and a globe valve?
Definition
A gate valve is used for on/off services and is not good when used for throttling or changing flow or pressure. A globe valve is used for throttling or changing pressure or flow in a process.
Term
What is a check valve? Where would you find one in a boiler room?
Definition
A check valve is a valve which only allows a fluid to flow in one direction. You would find one on a feed-water line to the boiler after the feed-water pump.
Term
What is a Non-Return valve? Where would you find one?
Definition
A Non-Return valve is a pressure assisted valve which allows steam to only travel in one direction. this valve is normally closed and only is opened when pressure over comes the valves closing pressure. You would normally find one on the steam output of a boiler.
Term
Which boilers require two main steam stop isolation valves?
Definition
When two or more boilers are connected to a common header and the boiler has a manhole. The 2 main steam stops should also have a free blow drain between them.
Term
Name at least 5 safety devices on a boiler.
Definition
Safety Valve, Low Water Cut-out, Flame Scanner, Process Controls, Pressure Gauge, Blow-down Valve, Gauge Glass and Water Column.
Term
What does a Safety Valve do?
Definition
Must discharge all off the steam a boiler can produce without allowing the pressure to rise more than 6% above the M.A.W.P.
Term
how many safety valves are required on a boiler?
Definition
There must be at least one safety valve on a boiler. Boilers with a heating surface over 500 square feet will have two or more.
Term
How often should safety valves be tested?
Definition
A safety valve will be tested on every start up of the boiler.
Term
At what pressure can you manually test the safety valves?
Definition
You can manually test the safety valves at 75% pressure.
Term
The pressure gauge reads 75PSI and the safety valve that is set to blow at 150PSI is blowing. What will you do?
Definition
First replace the pressure gauge, if the problem still exists and the gauge is correct, lift the handle of the safety to try to get it to seal. If the problem still exists, remove the boiler from service and have the valve repaired by a qualified technician or the OEM.
Term
What is saturated steam? What is superheated steam?
Definition
Saturated Steam is steam that has moisture in it. It is the steam that is in the drum and is at the same temperature as the water. Superheated Steam is steam that is removed from the drum and heated again to remove any moisture that may exist.
Term
What is Latent Heat and what is Sensible Heat?
Definition
Latent heat is the heat added to a substance that causes a change in state but not a change in temperature. Sensible heat is heat that is measured with a thermometer.
Term
What is a B.T.U.?
Definition
A B.T.U. us a British Thermal Unit or the amount of heat required to raise 1 pound of water 1 Degree Fahrenheit.
Term
How many BTU's are required to change water at 212°F to steam at 212°F?
Definition
970.3 BTU's are required.
Term
What is a Gauge Pressure? What is Absolute Pressure?
Definition
Gauge Pressure is the pressure read from a gauge. At atmospheric conditions it will read Zero. Absolute Pressure is the pressure of the surroundings or 14.7PSA. (When reading a gauge glass add 14.7 to what the gauge reads and you will have the PSIA.)
Term
As pressure increases, what happens to the Boiler Point of water?
Definition
The Boiling Point also increases.
Term
As pressure increases what happens to the Latent Heat of Evaporation?
Definition
The Latent Heat of Evaporation increases until 460PSIA and then decreases.
Term
Convert 60°C to Degree's Fahrenheit.
Definition
F=(1.8 X Celsius)+ 32. (1.8 X 60 = 108, Add 32, Total = 140°F)
Term
Convert 90°F to Degree's Celsius.
Definition
C=(F-32)÷1.8 (90-32 = 58, Divide by 1.8, Result = 32.2°C.)
Term
How much pressure will a column of water 10 feet high exert at it's base?
Definition
4.33PSI
Term
What doe the following numbers represent? 970.3, 2.31, .491 and 14.7?
Definition
(A.) 970.3 is the amount of BTU's added to convert 1 pound of water at 212°F to steam at 212°F (Latent Heat of Evaporation)
(B.) 2.31 is a column of water with a height of 2.31 feet will exert 1PSI at its base.
(C.) .491 is the conversion fact from inHG to PSI
(D.) 14.7 is atmospheric pressure at sea level.
Term
What is Radiation, Conduction, and Convection?
Definition
Radiation is heat transferred by light waves (i.e. heat from the sun). Conduction is Heat transferred by currents in a fluid (i.e. HRSG heat transfer). Convection is Heat transferred from one molecule to another (i.e. chemical reaction).
Term
What is an economizer? What is an Air Pre-Heater? What is a D.A.?
Definition
an Economizer takes heat from the flue gas and heat from the feed-water to increase boiler efficiency. An Air Pre-Heater takes heat from the boiler flue gas and heats the air which is mixed with the products of combustion to help increase overall boiler efficiency. A Deairator or D.A. is an open water feed heater which mixes steam and feed water.
Term
Name Three things that the D.A. does.
Definition
It acts as a feed-water storage tank, heats feed-water and removes noncondesible gases from the feed-water such as air.
Term
What is a Free-Flowing drain?
Definition
A drain that flows freely so it is visible and not directly into a pipe or vessel.
Term
What does a Super-heater do?
Definition
Takes Super-heater takes saturated steam from the steam drum and heats up the steam until no moisture is present.
Term
What is a Dry-Pipe?
Definition
A Dry-Pipe ensures that the saturated steam coming from an HRT or Scotch Marine boiler is dry or has no moisture droplets in it.
Term
When should the steam drum vent be opened or closed?
Definition
Should be open on start up until the pressure reaches 25% and closed until shut down when the pressure falls to 25% or below.
Term
Why are Super-Heaters fitted with drains?
Definition
To keep steam flowing through the Super-heater to protect the tubes from overheating and failing on start up or shut down.
Term
What is an Open Feed-Water Heater? A Closed Feed-Water Heater?
Definition
A Open Feed-Water Heater is one that allows water and steam to mix. A Closed Fee-Water Heater does not allow the water and steam to be mixed but allows heat transfer.
Term
What does M.A.W.P. stand for?
Definition
Maximum Allowable Working Pressure.
Term
How many BTU's in 1 Boiler Horsepower?
Definition
33,475 BTU's in 1 Boiler Horsepower. (970.3 X 34.5)
Term
What is an HRT Boiler?
Definition
A boiler where the products of combustion are inside the tubes, It was externally fired on coal.
Term
How is an HRT Boiler supported?
Definition
Either it was hung by lugs and rollers or suspended by the refractory.
Term
Which part of an HRT Boiler requires staying?
Definition
The boiler heads require staying.
Term
What is the closing-in line on an HRT Boiler?
Definition
This is where the boiler shell meets the refractory wall.
Term
Why are HRT boilers sloped or angled to the rear head?
Definition
They are sloped or angled to the rear to allow the boiler to be blown down for sediment or water chemistry control.
Term
How can you tell if an HRT Boiler has settled?
Definition
You can tell by the circumference of the blow-down pipe. It is found at the blow-down connection.
Term
What is a reinforcing pad? Where would you find it?
Definition
It is a plate added to the shell of the boiler for better thread penetration. It is found at the blow-off connection.
Term
What is a bag? Where could you find one on an HRT Boiler?
Definition
A Bag is caused by the build up of sediment on the inside of the shell of an HRT Boiler. The bag is formed when the sediment heats up and over time distorts the metal to create a bag like affect on the boiler shell. A Bag can be found on the heating surface of the shell of an HRT Boiler.
Term
How would you calculate the heating surface of an HRT Boiler.
Definition
Parts of the boiler with the products of combustion on one side and water on the other. You would measure the hot gas side parts. The heating surface is usually given in feet squared.
Term
Why would the blow-off pipe be located in the front of an HRT Boiler?
Definition
If the boiler was converted from coal to fuel oil. The oil would be piped in sending the flame further back on the HRT shell. The HRT would then need to be sloped or angled forward and the blow off pipe would then need to come to the front of the HRT as well.
Term
What is the difference between between an HRT and a Scotch Marine Boiler?
Definition
An HRT is externally fired while a Scotch Marine is internally fired.
Term
How much gas passes are in a Scotch Marine boiler?
Definition
A Scotch Marine typically had 3 gas passes.
Term
What is the difference between a Dry-Back and a Wet-Back Scotch Marine Boiler?
Definition
A Wet-Back Scotch Marine Boiler has a leg of water in the back for more heating surface and a Dry-Back did not.
Term
What is a Package Boiler?
Definition
A Package Boiler is a boiler which can easily be transported from site to site. A Package Boiler is usually built completely in a shop and transported to site, hooked up and fired.
Term
How many gas passes in a Package Boiler?
Definition
There are usually 4 gas passes in a typical package boiler.
Term
Describe the water circulation in a Stirling Boiler.
Definition
Water comes into the rear drum, then through a down comber then up the front drum, then to the middle drum and then back to the mud drum.
Term
What does baffling do in a boiler? What would make you believe you have a problem with the baffles?
Definition
Baffles in a boiler direct the flow of combustion gases over the boilers heating surfaces. If you had a high stack temperature you may have a failed baffle plate.
Term
Why are water tubes flared? Why are fire tubes beaded over?
Definition
Water tubes are flared so that they won;t fall out of the boiler. Fire tubes are beaded to keep a water tight seal between the fire tubes and the drum heads.
Term
Name three reasons we need blow-down valves.
Definition
They control chemistry in the boiler by removing sludge and sediment, help control high water levels, drain the boiler for cleaning and inspection, control chemical concentration in the boiler.
Term
How do you blow-down a boiler?
Definition
1. Find the true water level.
2. Have 1/2 a gauge glass full or better.
3. Open cooling water to blow-down tank.
4. Open quick opening valve or inside valve
5. Open slow opening or outside valve wide
6. Shut the outside or slow closing valve.
7. Close the inside valve or quick closing valve.
8. Check site glass
9. Secure cooling water to blowdown tank
Term
How do you blow-down a boiler when the gauge glass is not in sight?
Definition
You must use a second person a second person to watch the gauge glass.
Term
How do you find the true Water Level?
Definition
1. Slowly open the water column drain wide then close.
2. If the boiler is equipped with a low water cutoff you must disable it.
3. Open the drain on the water glass.
4. Open quick opening valve or inside valve.
5. Open slow opening or outside valve wide.
6. Shut the outside or slow closing valve.
7. Close the inside or quick closing valve.
8. When the level stabilizes check with tri-cocks.
9. Reactivate the low water cut-off.
Term
Explain how you would blow-down a gauge glass.
Definition
1. Open the drain on the water glass.
2. Close the top valve and blow-out the bottom connection.
3. Close the bottom valve and open the top valve to blow-out the top connection.
4. Close the drain valve.
5. Open the top valve.
6. When the level stabilizes check with tri-cocks.
Term
Which safety valve will lift first, drum or super-heater? Why?
Definition
The super-heater safety valve are set to lift first, this is so steam will travel through the super-heater always to keep the tubes from overheating and failing.
Term
What are the controlling factors of single, double, and triple element Feed-Water Regulators?
Definition
Single: controlled on water level only.
Double: Senses drum level and steam flow.
Triple: Controls on drum level, Feed-Water Flow and Steam Flow.
Term
Explain the operation of a Thermo-expansion Feed-Water Regulator.
Definition
They work when steam and water occupy a tube that is on a slight incline. As water level drops the steam space inside the tube expands. The expanding tube is connected to a linkage which will open the water valve as more steam occupies the tube than water.
Term
Explain the operation of a Thermo-hydraulic Feed-Water Regulator.
Definition
It works by head pressure. As level goes high, the head pressure of the water and pushes on the diaphragm of the which closes it down sending less water to the drum. Consequently, when more steam occupies the tube, the head the head pressure decreases and releases the diaphragm in the valve allowing it to open more to allow more water flow.
Term
Define Perfect, Complete, and Incomplete combustion.
Definition
Perfect: The complete burningof the fuel using a theoretical amount of air with no unused air or fuel. This will give you the hottest flame.
Complete: Completely burning all of the fuel while using excess air.
Incomplete: When not all of the fuel is burned.
Term
What is Primary Air, Secondary Air, and Tertiary Air?
Definition
Primary: Air that is used to control the rate of combustion.
Secondary: Air that is used to increase the efficiency of combustion.
Tertiary: Third source of air entered into combustion usually used for burning solid fuels.
Term
What are the three T's of combustion?
Definition
Time, Temperature, and Turbulence.
Term
What are the Combustibles in Fuel Oil?
Definition
Carbon, Hydrogen, and Sulfur.
Term
What is Excess Air?
Definition
The amount of air supplied above the the theoretical air for perfect combustion.
Term
What is Balanced Draft, Forced Draft, and Induced Draft?
Definition
Balanced: The use of a forced draft and induced fan together.
Forced: The use of a draft fan forcing outside air into the furnace, which creates a positive pressure on the furnace.
Induced: The use of a fan after the furnace, pushing air up the stack, which creates negative pressure on the furnace.
Term
Name two types of Air Pre-Heaters.
Definition
Tubular and Regenerate.
Term
What is Draft? How is it measured?
Definition
Draft is the movement of air through a furnace caused by warm air rising due to density. It is measured with a manometer. (U-tube or Inclined Tube)
Term
What is air made up of, by volume and weight?
Definition
Air by volume is made up of 20.91% Oxygen and 79.09 Nitrogen. By weight it is 23.13% Oxygen and 76.85% Nitrogen.
Term
What is Specific Gravity? What is Specific Heat?
Definition
Specific Gravity is the wight of any substance when compared to the weight of water. Specific Heat is the Amount of Heat required to raise the temperature of one pound of any substance one Degree Fahrenheit.
Term
How many Gallons in a Barrel of Oil?
Definition
42 gallons in a Barrel.
Term
What is Smoke? What causes it?
Definition
Smoke is visible emissions and is caused by incomplete combustion.
Term
Name two means of atomizing fuel oil.
Definition
1. Rotary Cup (Mechanical). 2. With High Pressure steam or air.
Term
Why do we purge a Boiler?
Definition
To remove any combustible gases that may still exist in the boiler.
Term
Explain how a Low Water Cut-Out works.
Definition
By sensing the level in a drum usualy by the site glass. When the water reaches a certain level, the low water cut-out will be activated. this device will remove the fires from the boiler as to protect the boiler from overheating due to low or no water in it.
Term
What is Pour Point, Flash Point, and Fire Point.
Definition
Pour: The lowest temperature at which oil will flow.
Flash: Temperature that oil will ignite (with a pop) but will continue to burn.
Fire: Minimum oil temperature which a flame will be sustained for at least 5 seconds.
Term
What would you do if you had a Flame Failure burning Oil.
Definition
Secure the fuel by closing the isolation valves, Purge the furnace and attempt to Re-Lite. During the Purge you can begin to Troubleshoot the cause of the Flame Failure.
Term
What percentages of CO2, O2, CO would you except burning oil.
Definition
Burning oil you would expect 12-14% CO2, 3-5% O2, and 0% CO.
Term
Explain how an Inverted Bucket Trap works.
Definition
It works by allowing the steam to enter the bucket and make the bucket buoyant. The bucket is in turn attached to a valve and the top of the bucket has a hole in it. As air and water collect they pass through the bucket and into the trap body, the bucket loses buoyancy and the bucket falls opening the valve and releasing the water and air. Once removed, steam will make the bucket buoyant again and the valve will close trapping the steam.
Term
What does a Steam Trap do?
Definition
Removes Air and Water from process steam increasing overall efficiency of the plant without the loss of steam.
Term
Name Four types of Steam Traps.
Definition
1. Float type
2. Inverted Bucket
3. Thermostatic
4. Thermodynamic.
Term
Explain Steam Injector works.
Definition
It works by flowing high pressure steam through a nozzle. When the steam exits the nozzle it creates a vacuum. At this point water or a fluid will be picked up by the vacuum and injected into the steam path.
Term
Explain how you would set the valves on a Duplex Pump.
Definition
1. Open the drains and close the steam and exhaust valves to perform LOTO.
2. Find the center of the piston by moving the piston rod all the way to each end making a mark. MEasure the distance between the marks and that will be the center.
3. Plum the rocker arm.
4. Center the valve square over the ports.
5. Equalize for lost motion.
6. Off center the valve.
7. Repeat for other side.
Term
What is the difference between a Rotary Pump and a Centrifugal Pump?
Definition
A Rotary Pump is positive displacement while a Centrifugal Pump is non-positive displacement.
Term
What is cavitation? How do you correct cavitation?
Definition
Cavitation is vapor bubbled in the fluid due to high temperature or low suction head. as these bubbles move towards high pressure areas within the pump the bubbles collapse and fluid rushes to fill the void. One would correct by either lowering the temp of the Feed-Water or lowering the flow the pump to raise suction head.
Term
Explain the procedure for starting a centrifugal pump.
Definition
Check and open the suction valve. Close the discharge valve. Prime the pump and if necessary vent the casing. Star the pump, when up to operating speed, open the discharge valve slowly.
Term
What do the numbers 10 X 6 X 12 mean in reference to a Duplex Pump.
Definition
10 is the diameter of the steam valve, 6 is the diameter of the water valve, and 12 is the length of the stroke.
Term
Explain what you would do if the Feed Pump tripped during normal.
Definition
If a feed pump trips and it is the only one, you attempt to restart it. If you have a standby, you would, knowing that the low water cut-off works, line up the pump and restart it.
Term
Where does make-up water come from?
Definition
From your service water system, which comes from surface water or ground water.
Term
What are the contaminants in make-up water?
Definition
Suspended Solids, Dissolved Solids and Dissolved Gases.
Term
Name two ways two ways to treat Make-Up Water.
Definition
Internally and Externally.
Term
What is Phosphate, Caustic Soda, and Sodium Sulfite used for?
Definition
Phosphate helps prevent scale from forming in the boiler.
Caustic soda which is used to raise the P.H. in a boiler.
Sodium Sulfite which is an Oxygen Scavenger.
Term
What is P.H.? How is it measured?
Definition
P.H. is the measure of a fluid alkalinity or acidity. It is measured on a scale of 0-14 with 7 being neutral.
Term
How do we test for Dissolved Solids?
Definition
By putting an electric charge through the water and measuring its resistance. The better the charge travels, the more the Dissolved solids there are.
Term
Why do we chemically treat condensate return lines?
Definition
By adding chemicals into the D.A. by means of metering pumps.
Term
How does a Zeolite water softener work?
Definition
It works by removing hard scale forming ions of calcium and magnesium and exchanges them for sodium ions which are soluable.
Term
Explain how you would replace a broken Gauge Glass.
Definition
1. Isolate the glass by closing the steam and water connections.
2. Open the gauge glass drain.
3. Have proper tools available (wire brush, wrench etc.)
4. If the gauge glass has a protector remove it.
5. Loosen nuts on gauge glass and remove glass and nuts. (wear gloves as the gauge may be hot and glass sharp)
6. Check connections for debris.
7. Wire brush and clean threads on glass connection.
10. Hand tighten the top connection unit.
11. Lift the glass 1/4 inch off the bottom connection and hand tighten the nut.
12. Slowly open the top steam connection to temper the glass.
13. With the top and bottom isolation open, close the drain.
14. If the glass leaks, isolate drain, and tighten up on nuts.
If you need to cut the gauge glass, measure from the top of the outside threads in the top connection to the bottom of the outside threads in the bottom connection and subtract 1.4 inch.