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1st Class Stationary Engineers Examination #2 Questions and Answers, Exams of Engineering

1st Class Stationary Engineers Examination #2 Questions and Answers

Typology: Exams

2024/2025

Available from 01/21/2025

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1st Class Stationary Engineers

Examination #2 Questions and Answers

All Boilers should be viewed as - Answer- Dangerous regardless of size and pressure One cubic inch of hot water under pressure expands to - Answer- almost one cubic foot of steam at atmospheric pressure Primary air is usually... - Answer- Blown into the combustion chamber, along with the fuel on a gas or oil burner. Heat always flows from ____ to ____ - Answer- hot to cold An accumulation test is used to determine - Answer- the relieving capacity of a safety valve Staging is a method used to - Answer- increase the pressure of a gas or liquid in step rather than all at once. All vacuum return heating systems require - Answer- traps Boiler water can be conditioned by - Answer- heating addition of chemicals and by blow down Water which contains scale-forming impurities is termed - Answer- hard water 33,478 BTUs equal - Answer- One boiler horsepower One purpose of automatic control is to insure - Answer- the safe operation of a system Is it possible to find all three types of heat transfer working at the same time? - Answer- Yes A vapor can best be defined as a - Answer- physical state between a liquid and a gas a firetube contains - Answer- the products of combustion a pigtail is used on a steam gauge connection to - Answer- prevent damage to the gauge

a convection type superheater - Answer- absorbs its heat from the hot gases of combustion All residential air conditioners use - Answer- Freon A hydrostatic test is a test for - Answer- the tightness of boiler drums and tubes One of the most important aspects of a boiler plant is the - Answer- Boiler supply One BTU will raise the temperature of one pound of water by - Answer- one degree fahrenheit Steam and water can be found - Answer- at the same temperature in a boiler Superheated steam is always - Answer- Dry at sea level, water boils at - Answer- 212 Degrees F Larger pipe sizes are found on - Answer- One pipe systems the explosion hazard in a oil-fired boiler is usually greatest when - Answer- Lighting off A good over the fire draft in a natural draft furnace should be approximately - Answer- .05 inches of water negative pressure A compound gage is calibrated to read - Answer- Vacuum and pressure An ammeter is always connected to an electric circuit in - Answer- Series with a shunt A two-stage air compressor contains - Answer- 2 Cylinders The heating surface of a tube in an HRT boiler is located - Answer- On the Outside The type of brace most commonly used in an HRT Boiler above the tubes is a - Answer- Diagonal stay Incomplete combustion in a boiler furnace is most often caused by - Answer- Insufficient amount of air The tensile strength of a boilerplate is - Answer- 55, Special types of fittings are used to take up the expansion in steam lines. One of these fitting is - Answer- Expansion joints

Which of the following is not an important consideration when burning coal? - Answer- The purge cycle of the burner Viscosity can best be described as an oil's ability to - Answer- Be Pumped. Heat transfer occurs in liquids and gases by means of - Answer- Convection A boiler pressure gauge gives readings in - Answer- Gauge pressure When water has absorbed as much heat as it can hold, it reached its - Answer- saturation point Which of the following elements causes boiler corrosion? Helium, Oxygen, Hydrogen, Nitrogen - Answer- Oxygen One example of a positive displacement pump is a - Answer- Reciprocating pump An economizer uses waste heat to raise the temperature of - Answer- Feed water the first thing an engineer should do to determine his true water level is - Answer- open the tri cock valves Which of the following is constructed from metal different from boilerplate? - Answer- Rivet One advantage gas has over fuel oil is it - Answer- Doesn't require storage space The real job of an oil burner is to - Answer- Atomize the oil Heat energy is measured in - Answer- BTU Oxygen can be removed from boiler feed water by - Answer- Heating An example of heat transfer by radiation is - Answer- Heat from the sun A valve generally used as a pressure shut-off valve is a - Answer- Gate valve The degree of hardness of boiler water can be determined by using - Answer- Soap Thermostatic traps contain a special element that opens and closes with a change in - Answer- temperature the vertical pipes used to connect steam mains with radiators are called - Answer- Risers A super heater - Answer- raises the temperature of steam

which of the following dose not produce a natural draft? temperature differential, pressure differential, The diameter of the stack, The height of the stack - Answer- The diameter of the stack The lower connection to a boiler gauge glass is located - Answer- 3" above the top row of tubes the greater the pressure in a boiler the - Answer- higher the boiling point the heart of the oil burner control system is the - Answer- Timer One of the most undesirable elements in coal is - Answer- Sulfur Air contains what percent of oxygen - Answer- 20% Specific heat is the amount of heat required to - Answer- Raise 1 lb of a substance 1 degree F Identify the five major parts of the refrigeration system marked with the letters A, B, C, D, and E. Identify each part that is lettered. - Answer- A = TEV: top part located above top row of tubes B = Evaporator: top row of tubes above the main refrigeration system C = Compressor: flask looking device on bottom left of diagram D = Condenser: bottom row of tubes next to compressor. E = Receiver: Very last device in diagram below the condenser. The "Pump" of an ammonia compression system - Answer- Compressor The "Storage Tank" for the refrigerant in a ammonia compression system - Answer- Receiver Cools the refrigerant and changes it from a gas to a liquid in a ammonia compression system - Answer- Condenser The coils that do the actual cooling in a ammonia compression system - Answer- Evaporator Regulates the amount of refrigerant entering the evaporator in a ammonia compression system - Answer- Expansion valve Eliminates non-condensable gases from the ammonia compression system - Answer- Purge Valve A specially constructed valve used on many receivers in a ammonia compression system - Answer- King Valve

Removes oil from the high-pressure side of the ammonia compression system - Answer- Oil Trap Protects the compressor from damage from slugs of liquid refrigerant in a ammonia compression system - Answer- False head Used when starting, stopping or pumping out the ammonia compression system - Answer- Suction and discharge valves New York State industrial code rules #'s 4 & 14 list 6 steps necessary to prepare a boiler for internal inspection. Name (6) of these steps. - Answer- 1. Secure the boiler, lockout and tag-out steam, fuel, electricity, water and compressed air.

  1. Allow the boiler to cool, then vent and drain.
  2. Remove manhole covers, hand hole covers, wash out plugs, low water cut out controls and the gauge glass.
  3. Clean the fire side (Tubes & combustion chamber) and the water side (Tubes, inner shell)/
  4. Make any necessary repairs. A device, which utilizes centrifugal force to remove moisture from steam. - Answer- Dry pipe Fan located in the boiler breeching - Answer- Induced Draft fan Fan located ahead of the fuel burner - Answer- Forced draft fan Heating device located before the feed pump and the boiler. - Answer- Open feed water heater Heating device located between the boiler and the feed pump - Answer- Closed feed water heater A device used to steady the discharge of a pump. - Answer- Air chamber Only used to remove oxygen from boiler condensate - Answer- Deaerator Coils located in the boiler breeching utilizing waste heat - Answer- Air preheater A temperature controlled device used in heating systems - Answer- thermostatic trap Used to increase the heat content of steam - Answer- super heater Prove by mathetmatics that one ton of refrigeration is equal to 12,000 BTU's per hour - Answer- 2000 lbs of ice melting / 24 hours x 144 Latent heat of fusion BTUs / lb

= 288,000 BTUs total in 24 hours = 12,000 BTU / hour Find the number of gallons in a tank 4 feet in diameter and 8 feet long? - Answer- Volume = D^2 x .pi/4 x length Volume = 4^2 x .7854 x 8 Volume = 100.53 ft^ 100.53 x 7.5 gallons / cu ft. = 754 gallons If the feed water temperature is 212 F and a boiler evaporated 7000 lbs of water at atmospheric pressure, what horsepower is developed? - Answer- 1 Boiler hp = 34.5 lbs of water evaporated from and @212 DegreesF 7000 lbs of water evaporated / 34.5 lbs/hr = 202.89 HP Convert -40Degrees centigrade to fahrenheit - Answer- C = (F-32) / 1. -40 = (F - 32) / 1. -72 = F - 32 -40 = F find the heating surface of a boiler tube 3" in diameter and 15' long - Answer- 3" tube / 12' = 1/4ft heating surface = D x pi x length x # of tubes Heating surface = .25 x 3.14 x 15 x 1 Heating surface = 11.78 ft^ How much current can 20 volts force through 5 ohms - Answer- V = IR 20 = I * 5 I = 4 amps What is the pressure at the base of a column of water 125' high? - Answer- 125' ft high x .434 psi / per ft. of rise = 54.25 psig Convert 86 Fahrenheit to centigrade - Answer- C = (F-32) / 1. C = (86-32)/1. C = 30 Degrees C How many BTUs are required to raise 100 cu. ft. of water from 32 F to water at 212 F? - Answer- Sp.h of water = 1 Sp.h of ice = 0. BTUs = sp.h x weight x temp diff BTUs = (1)(1)(212-32) BTUs = (1)(1)(180) = 180 BTUs / lb 100 cu. ft of water x 62.5 lbs / cu. ft = 6250 lbs of water 6250 lbs of water x 180 BTUs / lb = 1,125,000 total BTUs

How many ohms of resitance will 550 volts force a current of 25 amps? - Answer- V = IR 550 = 25 * R 22 ohms = R