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1st Class Stationary Engineers Examination #2 Questions and Answers
Typology: Exams
1 / 7
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.
= 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