Term
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Definition
| A Boiler is a closed vessel in which water, under pressure, is transformed into steam by the application of heat |
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Term
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Definition
| A Pressure Vessel is a closed vessel in which the source of pressure is external to itself. Any pressure vessel not identified as a boiler. |
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Term
| How Often must boilers be inspected? |
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Definition
| All boilers operating over 15 PSI unless otherwise exempt shall be inspected internally and externally every year. |
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Term
| How much notice is required to prepare a boiler for inspection? |
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Definition
| 14 days for an internal inspection, No notice required for external inspection. |
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Term
| Which air tanks require inspection? |
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Definition
| Air tanks at any pressure exceeding 50 PSI. |
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Term
| How does Chapter 146 determine Boiler Horsepower? |
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Definition
1. manufacturers tag if available
2. Steam output divided by 34.5
3. BTU/HR input divided by 41,840
4. BTU/HR output divided by 33,475 |
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Term
| How does Chapter 146 determine engine Horsepower? |
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Definition
| By the formula: P.L.A.N. divided by 33,000. P= Pressure Constant. L= Length of the stroke, A= area of the high pressure piston, N= Number of strokes per minute. |
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Term
| How does Chapter 146 determine turbine Horsepower? |
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Definition
| By the outside diameter of the turbine steam supply pipe |
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Term
| What can one do with a Second Class Fireman's License? |
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Definition
| Operate any boiler or boilers under the engineer of fireman in direct charge thereof |
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Term
| What information is on the Certificate of Inspection? |
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Definition
| Name of owner/user, Location, Size and number of boiler, D.O.I., Signature of inspector, M.A.W.P. |
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Term
| Where is the operators license kept? |
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Definition
| Located in the boiler room engine room where it can be easily read |
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Term
| What boiler horsepower requires "periodic attendance"? |
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Definition
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Term
| What boiler horsepower requires "non-continuous attendance"? |
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Definition
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Term
| What boiler horsepower requires "continuous attendance"? |
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Definition
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Term
| Who can appeal the results of a license exam? |
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Definition
| A person aggrieved by the action of a single exam may, within one week, therefrom to the chief |
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Term
| List 4 methods used to classify boiler types |
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Definition
1. Direction of axis
2. According to use
3. Location of furnace
4. Operating Pressure
5. Fire tube/Water Tube |
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Term
| What is a fire tube boiler? |
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Definition
| Has the products of combustion inside the tubes which are surrounded by water |
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Term
| What is a water tube boiler? |
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Definition
| Boiler in which water circulates in tubes heated externally by the products of combustion |
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Term
| What is the difference between a dry-top vertical boiler and a wet-top vertical boiler? |
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Definition
| Dry-top vertical boiler has tubes which extend beyond the normal operating water level. Wet-top vertical the tubes are completley submerged by water. |
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Term
| What does H.R.T. stand for? |
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Definition
| Horizontal Return Tubular |
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Term
| why are H.R.T. boilers sloped to the rear head? |
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Definition
| So the sludge will be at an angle and can be easily removed by opening the blow off valve |
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Term
| Name two methods used to support H.R.T. boilers |
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Definition
| Sitting on the brick structure with lugs and rollers, or by overhead suspension from large beams |
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Term
| Name two types of Scotch Marine boilers |
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Definition
| Stationary service or Dry Back and Marine service or wet back |
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Term
| What is the primary difference between an H.R.T. and a Scotch Marine boiler? |
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Definition
| H.R.T.'s are externally fired while Scotch Marine's are internally fired |
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Term
| Name 5 advantages of a fire tube package boiler |
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Definition
| Low Cost, Turnkey Operation, Limited Space Requirements, No Setting, Automatic Operation. |
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Term
| How are water tube boilers classified? |
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Definition
| As straight tube, bent tube and/or the number of drums: multiple drums, single drum, or no drum |
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Term
| Why are water tube boilers used in electric-generating plant? |
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Definition
| Unlimited capacity and almost limitless pressure capability |
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Term
| Name 5 different types of water tube boilers |
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Definition
| B+W longitudinal/cross drum, Heine boiler. Stirling boiler, Controlled Circulation, Forced Flow Circulation, Natural Circulation, Electric boilers, HRSG |
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Term
| How many pressure gauges are required on a boiler? |
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Definition
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Term
| How many safety valves are required on a boiler? |
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Definition
| At least one. Boilers operating over 500 square feet of heating surface require two or more |
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Term
| What is the purpose of a hand hole? A manhole? |
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Definition
| A hand hole is so a worker can access a part of a boiler with his hand to inspect/and or fix. A man hole is so a worker can enter the boiler to inspect and/or fix. |
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Term
| Name 3 special purpose boilers |
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Definition
| Electric boilers, Miniature boilers, Hot water boilers, Fluidized Bed Boilers |
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Term
| What does H.R.S.G. stand for? |
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Definition
| Heat Recovery Steam Generator |
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Term
| What is the longitudinal joint? A circumferential joint? |
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Definition
| Longitudinal runs the entire length of the shell/drum and is used to form a closed cylinder, a Circumferential Girth seam is used to attach heads to the formed cylinder |
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Term
| What is a water column used for? |
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Definition
| to reduce the turbulence of the water in the boiler so that an accurate level can be seen in the gauge glass. |
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Term
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Definition
| Has wedge-shaped disc that is raised to open and lowered to close the valve. Used to fully open or totally close. |
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Term
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Definition
| A round disc or tapered plug-type disc that seats against a port to close the valve. Used where throttling and/or when frequent operation is required. |
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Term
| What is the purpose of the main steam stop valve? |
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Definition
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Term
| What is the purpose of the Non-Return Valve? |
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Definition
| Only allow flow in one direction. |
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Term
| Explain how you would "cut in" a boiler equipped with a non-return valve |
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Definition
| Place a fire in the boiler, Open the bypass valve, warm the steam line from the header, open the outside steam stop valve and close bypass, at 80% pressure open the stem on the non-return valve. When boiler exceeds header pressure the NRV will open and the boiler will come on line. Close the free blow drain. |
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Term
| When is more than one blow-down valve required? |
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Definition
| When it has more than 100psi |
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Term
| What is a slow opening valve? What is a quick opening valve? |
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Definition
| A slow opening valve requires more than five full turns to be fully open. A quick opening valve requires less than five full turns to be fully open. |
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Term
| Explain how you would blow down a boiler |
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Definition
| Find the true water level, have a 1/2 gauge glass or better, open cooling water to the blow down tank, open quick opening valve, open slow opening valve fully wide and close it, close quick opening valve, check level and secure cooling water to blow down tank |
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Term
| Explain the principle of operation of a bourdon tube pressure gauge |
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Definition
| A hollow bent tube, made of brass, as pressure is added it wants to straighten |
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Term
| What is a siphon? What is a snubber? |
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Definition
| Siphon: Keeps live steam out of the Bourdon tube. Snubber: separation of live steam and keeps a constant pressure |
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Term
| What is the purpose of a water column? |
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Definition
| Reduce the turbulence of water level |
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Term
| How do you blow down a water column? |
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Definition
| Open the drain valve fully wide then closing it. Remember to disable the low water cut-out if you do not want the boiler to trip. |
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Term
| How do you blow down a gauge glass? |
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Definition
| 2 valves independently, to ensure that neither connection is plugged |
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Term
| Explain how you would test a low water cutout |
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Definition
| Cut off feed supply and drain the water column |
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Term
| What is a closed feed water heater? |
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Definition
| When steam and water do not come into direct contact. |
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Term
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Definition
| Allows flow in only one direction |
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Term
| Where in the plant are you likely to find a check valve? |
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Definition
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Term
| What is a cyclone separator? |
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Definition
| Spins the steam to separate water from steam |
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Term
| Where would a cyclone separator be located? |
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Definition
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Term
| What is the purpose of a flash tank? |
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Definition
| A blow down tank that recovers heat from the blow down |
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Term
| What is Potential Energy? Kinetic Energy? |
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Definition
| Potential energy is energy possessed by reason of position or deformation. Kinetic energy is energy possessed by reason of motion. |
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Term
| What are the First and Second Laws of Thermodynamics? |
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Definition
| 1st: Energy cannot be created or destroyed but may be converted from one form to another. 2nd: No machine, actual or ideal, can both continuously and completely transform heat into mechanical energy. Nothing is 100% efficient. |
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Term
| Name three ways that heat is transferred |
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Definition
| Radiation, Convection, Conduction |
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Term
| What is a British Thermal Unit? |
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Definition
| A BTU is the amount of heat required to raise the temperature of One Pound of water one degree Fahrenheit. |
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Term
| Convert 22° Celsius to °Fahrenheit. |
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Definition
| Multiply 22° by 1.8 (which equals 39.6), then add 32, which makes a total of 71.6°F. |
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Term
| Convert 105°F to °Celsius |
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Definition
| Subtract 105° by 32 (which equals 73), and then divide by 1.8 which brings you to 40.56°C |
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Term
| How many BTU's are required to raise one pound of water from 50°F to 210°F? |
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Definition
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Term
| How many BTU's are requires to raise the temperature of 500 GALLONS of water from 70°F to 160°F? |
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Definition
| Convert GALLONS to pounds by multiplying 500 by 8.33 (which equals 4165), then multiply the BTU's from 70°F to 160°F (which is 90 BTU's) by 4165 and the total BTU's is 374,850 BTU's. |
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Term
| You have a 2,000 GALLON tank filled with water, how much does the water weigh? |
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Definition
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Term
| The pressure gauge reads 130 PSI, what is the Absolute Pressure? |
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Definition
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Term
| What is the Latent Heat of Fusion? |
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Definition
| Heat added to solid to cause a change of state to a liquid. (One pound of Ice at 32°F becomes Water with the addition of 144 BTU's of heat) |
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Term
| What is the Latent Heat of Evaporation? |
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Definition
| Heat added to a liquid to cause a change of state to a gas/vapor. (One pound of water at 212°F becomes one pound of steam at 212°F when 970.3 BTU's of heat are added) |
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Term
| How many BTU's in a pound of steam at 212°F? |
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Definition
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Term
| What is Sensible Heat and Latent Heat? |
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Definition
| Sensible Heat is heat that is added to a substance that causes a change in temperature that can be measured with a thermometer. Latent heat is heat that is added to a substance that causes a change of state without a change in temperature. |
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Term
| What is the critical pressure of steam? |
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Definition
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Term
| What is the critical temperature of steam? |
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Definition
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Term
| What happens to the boiling point of water as the pressure increases? |
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Definition
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Term
| What happens to the Enthalpy of Evaporation as the pressure increases? |
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Definition
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Term
| What are the three states of matter? |
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Definition
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Term
| What is the definition of specific heat? |
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Definition
| The amount of heat required to raise the temperature of one pound of any substance one °F |
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Term
| A boiler is equipped with one safety valve, where will it be set to blow? |
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Definition
| At or below the Max Allowable Working Pressure |
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Term
| A boiler is equipped with three safety valves, where can they be set? |
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Definition
| One valve would be set at or below the M.A.W.P., one could be set 3% above the M.A.W.P., and the third would be within 10% of the highest set safety valve. |
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Term
| Where is the super heater safety valve set? |
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Definition
| The super heater safety valve is the lowest set safety valve to assure flow through the super heater to prevent overheating |
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Term
| Name three methods used to determine the minimum safety valve relieving capacity |
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Definition
| Table PG-70 (Code constants), Code formula(W= CxHx.75) divided by 1100), Accumulation test, and by measuring the maximum evaporative capacity of the feed water |
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Term
| Why does a safety valve pop open? |
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Definition
| due to the huddling chamber, i.e. an increased area of the disk is subjected to high pressure steam quickly overcoming spring tension |
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Term
| What type of valve(s) are permitted between the boiler and the safety valve? |
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Definition
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Term
| How are soot blowers classified? |
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Definition
| Retractable or Stationary |
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Term
| What precautions should be taken prior to soot blowing? |
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Definition
| Increase air flow, drain steam lines to soot blower(s), blow soot from the furnace outward |
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Term
| How are opacity excursions handled during soot blowing? |
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Definition
| stop blowing soot and proceed slowly to avoid further excursions |
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Term
| If you fail a written exam, when can you apply again? |
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Definition
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Term
| What is the purpose of a steam trap? |
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Definition
| Increase overall efficiency by removing air and water from steam lines without a loss of steam |
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Term
| Name three types of steam traps |
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Definition
| Inverted Bucket, Flat & Thermostatic (F&T), Thermodynamic |
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Term
| Describe the operation of any single steam trap |
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Definition
| Thermostatic: A temperature sensitive bi-metallic strip opens and closes a valve. It reacts to the difference in temperature between the steam and condensate and closes due to Live Steam |
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Term
| How would you know a steam trap was not working? |
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Definition
| Steam process not working, trap not cycling, low or no temperature differential across the trap, high temperature condensate returns |
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Term
| If you fail a written exam, how soon can you apply again? |
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Definition
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|
Term
| Where is a non-return valve located? |
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Definition
| As close to the boiler as possible |
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Term
| Explain how you would find the true water level |
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Definition
| Open drain to water column and close, Open gauge glass drain and blow out the top and bottom gauge glass connections independently and close gauge glass drain. Check water level with tri-cocks |
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Term
| How often must air tanks be inspected? |
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Definition
| Air tanks operating at 50PSI and above should be inspected every two years |
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Term
| How often should high pressure boilers be blown down? |
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Definition
| At least once a day, it is better to base the blow down frequency on water analysis |
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Term
| Can you stop a safety valve from chattering by taking up on the adjusting nut? |
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Definition
| You should not. Only be made by the manufacturer or his authorized representative |
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Term
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Definition
| A chemical process in which a combustible unites with oxygen to produce heat and often light. |
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Term
| What is Perfect Combustion? |
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Definition
| Burning fuel completely while using only the theoretical amount of air required. (Not possible) |
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Term
| What is Complete Combustion? Incomplete Combustion? |
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Definition
| Complete: Burning the fuel completely using the minimum amount of excess air. (Desirable) Incomplete: Not burning all the fuel. (Not good!) |
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Term
| What is Spontaneous Combustion? |
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Definition
| Combustion which occurs without an external ignition source. |
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Term
| What conditions are necessary for complete combustion? |
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Definition
| The three T's. Time, Temperature, and Turbulence. |
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Term
| What are the combustibles in fuel? |
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Definition
| Carbon, Hydrogen, and Sulfur |
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Term
| What is Primary Air and Secondary Air? |
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Definition
| Primary air: Air supplied to the burner with the fuel that controls the rate of combustion as well as the amount of fuel that can be burned. Secondary: Air supplied to the combustion process that controls combustion efficiency; How completely the fuel is burned. |
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Term
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Definition
| The amount of air supplied to the combustion process that is greater than the theoretical amount required |
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Term
|
Definition
| The internal resistance of fuel oil to flow. |
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Term
| What is Pour Point, Flash Point, and Fire Point? |
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Definition
| Pour: The lowest temp. at which an oil will still flow. Flash: The temp. that an oil will ignite with a "pop" but not continue to burn. Fire: The temp that an oil will ignite and continue to burn. |
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Term
| Name three ways to atomize #6 oil. |
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Definition
| Mechanical Burners (Rotary Cup), Pressure Atomization and Steam/Compressed Air Atomization. |
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Term
| Give five reasons a boiler burning #6 oil would smoke. |
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Definition
| If there is not enough air supplied, Cold Oil, Insufficient Oil Pressure, Low Atomizing Pressure, cold Boiler, Dirty/Plugged Burner tips. |
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Term
| Name the necessary components of a #6 fuel oil system. |
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Definition
| Storage tanks, Pumps, Strainers, Heaters, Pressure Gauges, Thermometers. |
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Term
| Name the types of Draft found in power plants. |
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Definition
| Mechanical Draft, Forced Draft, Induced Draft, Balanced Draft, Natural Draft |
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Term
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Definition
| Using a manometer (U-Tube or Inclined Tube), which tells inches or tenths of inches of a vertical water column. |
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Term
| What is the greatest heat loss in a boiler? |
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Definition
| The heat lost out the stack is the greatest heat loss in a boiler. |
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Term
| How many BTU's in a gallon of #6 oil? |
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Definition
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Term
| How many gallons in a barrel of fuel oil? |
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Definition
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Term
| What do you do if the flame is lost while burning #6 oil? |
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Definition
| Secure the fuel, Purge the Furnace, Re-lite |
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Term
| What is an Opacity Violation? |
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Definition
| The emission of smoke which has a shade or appearance equal or greater than #1 of the chart for a period of six minutes during any one hour. |
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Term
| What are the Two major categories of Pumps? |
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Definition
| Positive Displacement Pumps and Non-Positive Displacement Pumps |
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Term
| Name Four general classifications of pumps |
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Definition
| Rotary, Jet, Centrifugal, Reciprocating |
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Term
| Explain the operation of a Fee-Water Injector |
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Definition
| It uses a condensable gas to entrain a liquid and discharge against a higher than either the motive or suction pressures. |
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Term
| What is the maximum feed-water temperature when using injectors? |
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Definition
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|
Term
| What are the operating mediums for duplex pumps? |
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Definition
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Term
| How do you set the valves on a duplex pump? |
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Definition
1. Close steam and exhaust valves. Drain pump and Tag Out Lock Out.
2. Center the Pistons
3. Plumb the Rocker arm
4. Square the valve over the ports
5. Equalize the lost motion
6. Move piston off center |
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Term
| What is meant by the term "Lost Motion"? |
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Definition
| Lost Motion is the amount the valve rod moves without moving the valve gear |
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Term
| What is the effect of too much lost motion? Not enough Lost Motion? |
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Definition
| Too much Lost Motion will cause the pistons to trike the heads, Not enough Lost Motion will cause the pump to Short stroke. |
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Term
| What is a Cushioned Valve? |
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Definition
| They are manual valves located at each end of the steam chest, they act as an added control to prevent the steam piston from striking the cylinder heads when the pump operates at high speeds. |
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Term
| What is the area of a piston 6" in diameter? |
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Definition
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|
Term
| Does a Duplex Pump displace an equal amount of water on the forward and reverse stroke? Why? |
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Definition
| Yes because it is traveling the same distance both ways and only a specific limit of fluids can enter into the piston chamber. |
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Term
| What type of pump is a Metering Pump? A Vacuum Pump? |
|
Definition
|
|
Term
| What type of service would you expect to see a Rotary Pump? A Gear Pump? |
|
Definition
|
|
Term
|
Definition
| The sudden formation and collapse of low pressure bubbles in water by mechanical forces. This occurs at the inlet of a centrifugal pump when the temperature of the water is too hot or when the suction is too low. |
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Term
| Explain what you would do if a pump began to cavitate |
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Definition
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|
Term
| What is the best way to avoid pump Cavitation? |
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Definition
| Make sure there is enough water at the correct temperature at all times |
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Term
| Explain the operation of a Centrifugal Pump |
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Definition
| A Centrifugal pump has an impeller attached to the shaft, as the impeller rotates, water enters the center and is thrown outward by Centrifugal force. The water leaves the impeller at a high velocity which is converted to pressure by a volute. |
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Term
| Name three advantages and disadvantages of a Centrifugal Pump. |
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Definition
Advantages: Cost-Effective, Easy to use,
Disadvantages: Can only pump water, Uses electricity, can break easily. |
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|
Term
| Define Head, NPSH, and Velocity Head. |
|
Definition
Head: The pressure Gravity adds
Net Positive Suction Head: The minimum suction conditions to prevent cavitation in a pump.
Velocity Head: The kinetic energy per round or the vertical distance a liquid would have to fall to acquire the stated velocity. |
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Term
| What do the numbers 8 X 6 X 12 refer to in a Duplex Pump? |
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Definition
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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. |
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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. |
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Term
| How often must high pressure boilers be inspected in Massachusetts? |
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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. |
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Term
| What information is on a Certificate of Inspection? |
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Definition
| Name or Owner/User, Location, Size and number of boiler, date of Inspection, Signature of Inspector, M.A.W.P. |
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Term
| How often must air tanks be inspected? |
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Definition
| Compressed air tanks, unless otherwise exempt, over 50PSI must be inspected every two years. |
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Term
| How often must refrigeration equipment be inspected? |
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Definition
| All refrigeration and air conditioning equipment requiring a certificate from the D.P.S. must be inspected at least once a year. |
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Term
| What is a ton of refrigeration? |
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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) |
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Term
| How does the D.P.S. determine Boiler Horsepower? |
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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. |
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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. |
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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. |
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|
Term
| Which boilers require only Periodic Attendance? |
|
Definition
| Boilers that have between 9 ans 250 Boiler Horsepower require periodic attendance. |
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Term
| What Boilers Require only Non-Continuous attendance? |
|
Definition
| boilers between 251 and 500 Boiler horsepower only Require Non-Continuous attendance. |
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|
Term
| What boilers require Continuous Attendance? |
|
Definition
| Boilers over 501 Boiler Horsepower require continuous attendance. |
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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. |
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|
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. |
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|
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. |
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|
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. |
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|
Term
| Name at least 5 safety devices on a boiler. |
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Definition
| Safety Valve, Low Water Cut-out, Flame Scanner, Process Controls, Pressure Gauge, Blow-down Valve, Gauge Glass and Water Column. |
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Term
| What does a Safety Valve do? |
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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. |
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Term
| how many safety valves are required on a boiler? |
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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. |
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Term
| How often should safety valves be tested? |
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Definition
| A safety valve will be tested on every start up of the boiler. |
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Term
| At what pressure can you manually test the safety valves? |
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Definition
| You can manually test the safety valves at 75% pressure. |
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Term
| The pressure gauge reads 75PSI and the safety valve that is set to blow at 150PSI is blowing. What will you do? |
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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. |
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Term
| What is saturated steam? What is superheated steam? |
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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. |
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Term
| What is Latent Heat and what is Sensible Heat? |
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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. |
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Term
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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. |
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Term
| How many BTU's are required to change water at 212°F to steam at 212°F? |
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Definition
| 970.3 BTU's are required. |
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Term
| What is a Gauge Pressure? What is Absolute Pressure? |
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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.) |
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Term
| As pressure increases, what happens to the Boiler Point of water? |
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Definition
| The Boiling Point also increases. |
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Term
| As pressure increases what happens to the Latent Heat of Evaporation? |
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Definition
| The Latent Heat of Evaporation increases until 460PSIA and then decreases. |
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Term
| Convert 60°C to Degree's Fahrenheit. |
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Definition
| F=(1.8 X Celsius)+ 32. (1.8 X 60 = 108, Add 32, Total = 140°F) |
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Term
| Convert 90°F to Degree's Celsius. |
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Definition
| C=(F-32)÷1.8 (90-32 = 58, Divide by 1.8, Result = 32.2°C.) |
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Term
| How much pressure will a column of water 10 feet high exert at it's base? |
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Definition
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Term
| What doe the following numbers represent? 970.3, 2.31, .491 and 14.7? |
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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. |
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Term
| What is Radiation, Conduction, and Convection? |
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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). |
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Term
| What is an economizer? What is an Air Pre-Heater? What is a D.A.? |
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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. |
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Term
| Name Three things that the D.A. does. |
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Definition
| It acts as a feed-water storage tank, heats feed-water and removes noncondesible gases from the feed-water such as air. |
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Term
| What is a Free-Flowing drain? |
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Definition
| A drain that flows freely so it is visible and not directly into a pipe or vessel. |
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Term
| What does a Super-heater do? |
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Definition
| Takes Super-heater takes saturated steam from the steam drum and heats up the steam until no moisture is present. |
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Term
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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. |
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Term
| When should the steam drum vent be opened or closed? |
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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. |
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Term
| Why are Super-Heaters fitted with drains? |
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Definition
| To keep steam flowing through the Super-heater to protect the tubes from overheating and failing on start up or shut down. |
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Term
| What is an Open Feed-Water Heater? A Closed Feed-Water Heater? |
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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. |
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Term
| What does M.A.W.P. stand for? |
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Definition
| Maximum Allowable Working Pressure. |
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Term
| How many BTU's in 1 Boiler Horsepower? |
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Definition
| 33,475 BTU's in 1 Boiler Horsepower. (970.3 X 34.5) |
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Term
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Definition
| A boiler where the products of combustion are inside the tubes, It was externally fired on coal. |
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Term
| How is an HRT Boiler supported? |
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Definition
| Either it was hung by lugs and rollers or suspended by the refractory. |
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Term
| Which part of an HRT Boiler requires staying? |
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Definition
| The boiler heads require staying. |
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Term
| What is the closing-in line on an HRT Boiler? |
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Definition
| This is where the boiler shell meets the refractory wall. |
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Term
| Why are HRT boilers sloped or angled to the rear head? |
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Definition
| They are sloped or angled to the rear to allow the boiler to be blown down for sediment or water chemistry control. |
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Term
| How can you tell if an HRT Boiler has settled? |
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Definition
| You can tell by the circumference of the blow-down pipe. It is found at the blow-down connection. |
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Term
| What is a reinforcing pad? Where would you find it? |
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Definition
| It is a plate added to the shell of the boiler for better thread penetration. It is found at the blow-off connection. |
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Term
| What is a bag? Where could you find one on an HRT Boiler? |
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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. |
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Term
| How would you calculate the heating surface of an HRT Boiler. |
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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. |
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Term
| Why would the blow-off pipe be located in the front of an HRT Boiler? |
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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. |
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Term
| What is the difference between between an HRT and a Scotch Marine Boiler? |
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Definition
| An HRT is externally fired while a Scotch Marine is internally fired. |
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Term
| How much gas passes are in a Scotch Marine boiler? |
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Definition
| A Scotch Marine typically had 3 gas passes. |
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Term
| What is the difference between a Dry-Back and a Wet-Back Scotch Marine Boiler? |
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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. |
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Term
| What is a Package Boiler? |
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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. |
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Term
| How many gas passes in a Package Boiler? |
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Definition
| There are usually 4 gas passes in a typical package boiler. |
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Term
| Describe the water circulation in a Stirling Boiler. |
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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. |
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Term
| What does baffling do in a boiler? What would make you believe you have a problem with the baffles? |
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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. |
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Term
| Why are water tubes flared? Why are fire tubes beaded over? |
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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. |
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Term
| Name three reasons we need blow-down valves. |
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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. |
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Term
| How do you blow-down a boiler? |
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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 |
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Term
| How do you blow-down a boiler when the gauge glass is not in sight? |
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Definition
| You must use a second person a second person to watch the gauge glass. |
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Term
| How do you find the true Water Level? |
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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. |
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Term
| Explain how you would blow-down a gauge glass. |
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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. |
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Term
| Which safety valve will lift first, drum or super-heater? Why? |
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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. |
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Term
| What are the controlling factors of single, double, and triple element Feed-Water Regulators? |
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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. |
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Term
| Explain the operation of a Thermo-expansion Feed-Water Regulator. |
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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. |
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Term
| Explain the operation of a Thermo-hydraulic Feed-Water Regulator. |
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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. |
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Term
| Define Perfect, Complete, and Incomplete combustion. |
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Definition
| Perfect: The complete burning of 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. |
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Term
| What is Primary Air, Secondary Air, and Tertiary Air? |
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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. |
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Term
| What are the three T's of combustion? |
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Definition
| Time, Temperature, and Turbulence. |
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Term
| What are the Combustibles in Fuel Oil? |
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Definition
| Carbon, Hydrogen, and Sulfur. |
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Term
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Definition
| The amount of air supplied above the the theoretical air for perfect combustion. |
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Term
| What is Balanced Draft, Forced Draft, and Induced Draft? |
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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. |
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Term
| Name two types of Air Pre-Heaters. |
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Definition
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Term
| What is Draft? How is it measured? |
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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) |
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Term
| What is air made up of, by volume and weight? |
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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. |
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Term
| What is Specific Gravity? What is Specific Heat? |
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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. |
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Term
| How many Gallons in a Barrel of Oil? |
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Definition
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Term
| What is Smoke? What causes it? |
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Definition
| Smoke is visible emissions and is caused by incomplete combustion. |
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Term
| Name two means of atomizing fuel oil. |
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Definition
| 1. Rotary Cup (Mechanical). 2. With High Pressure steam or air. |
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Term
| Why do we purge a Boiler? |
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Definition
| To remove any combustible gases that may still exist in the boiler. |
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Term
| Explain how a Low Water Cut-Out works. |
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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. |
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Term
| What is Pour Point, Flash Point, and Fire Point. |
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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. |
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Term
| What would you do if you had a Flame Failure burning Oil. |
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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. |
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Term
| What percentages of CO2, O2, CO would you except burning oil. |
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Definition
| Burning oil you would expect 12-14% CO2, 3-5% O2, and 0% CO. |
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Term
| Explain how an Inverted Bucket Trap works. |
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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. |
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Term
| What does a Steam Trap do? |
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Definition
| Removes Air and Water from process steam increasing overall efficiency of the plant without the loss of steam. |
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Term
| Name Four types of Steam Traps. |
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Definition
1. Float type
2. Inverted Bucket
3. Thermostatic
4. Thermodynamic. |
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Term
| Explain Steam Injector works. |
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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. |
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Term
| Explain how you would set the valves on a Duplex Pump. |
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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. |
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Term
| What is the difference between a Rotary Pump and a Centrifugal Pump? |
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Definition
| A Rotary Pump is positive displacement while a Centrifugal Pump is non-positive displacement. |
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Term
| What is cavitation? How do you correct cavitation? |
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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. |
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Term
| Explain the procedure for starting a centrifugal pump. |
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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. |
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Term
| What do the numbers 10 X 6 X 12 mean in reference to a Duplex Pump. |
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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. |
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Term
| Explain what you would do if the Feed Pump tripped during normal. |
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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. |
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Term
| Where does make-up water come from? |
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Definition
| From your service water system, which comes from surface water or ground water. |
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Term
| What are the contaminants in make-up water? |
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Definition
| Suspended Solids, Dissolved Solids and Dissolved Gases. |
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Term
| Name two ways two ways to treat Make-Up Water. |
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Definition
| Internally and Externally. |
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Term
| What is Phosphate, Caustic Soda, and Sodium Sulfite used for? |
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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. |
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Term
| What is P.H.? How is it measured? |
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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. |
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Term
| How do we test for Dissolved Solids? |
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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. |
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Term
| Why do we chemically treat condensate return lines? |
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Definition
| By adding chemicals into the D.A. by means of metering pumps. |
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Term
| How does a Zeolite water softener work? |
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Definition
| It works by removing hard scale forming ions of calcium and magnesium and exchanges them for sodium ions which are soluable. |
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Term
| Explain how you would replace a broken Gauge Glass. |
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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. |
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