Browse all practice questions for the 4th Class Power Engineering 4B7 Practice Exam. Search by topic, open any question and review its full explanation, then test yourself in the practice quiz.

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  • An essential auxiliary in a gas turbine installation is?
  • In the valve train, which component lies between the valve and the pushrod?
  • Which parameter primarily determines the output power of a gas turbine?
  • Which description correctly defines forced-draft and induced-draft operation?
  • Which statement about turbine overspeed trip is accurate according to standard practice?
  • An arrangement of a steam system and a gas turbine, working as a single installation, is called a
  • Turbine lubricating oil:
  • A two-shaft gas turbine arrangement typically involves
  • What is steam quality and why is dryness fraction important for turbine equipment?
  • Which statement correctly describes the role of dampers in stack draft control?
  • Economizers are used to:
  • Most modern gas turbines use a ______ shaft design.
  • How does excess air affect boiler efficiency and fuel usage?
  • Which instruments and components are commonly used for drum level control, and what problems can affect them?
  • Which of these best describes signs of suboptimal combustion in a fuel-fired boiler?
  • What is feedwater and why must it be treated before entering a boiler?
  • What is the purpose of condensate return in a steam plant?
  • In a four-stroke engine, which statement about valve operation is true?
  • Why should feedwater pressure be managed in conjunction with drum level?
  • Which cooling method is used for large internal combustion engines?
  • What is the effect of silica fouling on heat transfer surfaces?
  • In cooling tower wood, when natural extractives are leached away, it becomes less able to resist what?
  • On steam turbines, carbon glands are:
  • What is the role of interlocks on the fuel and air supply in boiler operation?
  • In impulse turbine theory, energy transfer to the blades is primarily achieved by which phenomenon?
  • The air pressure used when starting a diesel engine with injected compressed air is approximately:
  • What causes the fuel to ignite in a diesel engine?
  • Which statement best describes the role of the camshaft?
  • Which statement about turbine overspeed trip is correct?
  • Why is silica control important in boiler water?
  • Why is boiler water pH and alkalinity control important?
  • How does thermal shock occur in boilers, and how can it be prevented?
  • What are three major objectives of boiler water treatment?
  • How would you detect a gas leak in a boiler room and what actions would you take?
  • Not a method to test a steam trap?
  • In gas turbine cycles, an open cycle implies
  • A turbine where the steam pressure drops only in stationary blades is called an impulse turbine.
  • Smaller spark ignition engines vaporize gasoline by which process?
  • Gas turbine performance is influenced by air density. Which statement is correct?
  • When starting a steam turbine it is customary practice to
  • Gas turbines are ideal in environments where which resource is scarce?
  • Which characteristic makes a gas turbine a favorable prime mover?
  • What is the primary purpose of a boiler's low-water cutoff (LWCO)?
  • To prevent cooling tower basin water from freezing in cold weather, many units use which method?
  • Which practice is part of safe boiler room operations to prevent accidental startup during maintenance?
  • The impulse turbine works on the principle that
  • Which device is used to ignite the fuel-air mixture in a gasoline engine?
  • Gas turbines are ideal where:
  • In a reaction turbine, how does the velocity change as steam passes through moving blades?
  • What common issue can cause drum level measurement to drift?
  • How does fouling of heat transfer surfaces affect boiler performance?
  • Which component supplies clean air to the regenerator?
  • How do you determine if condensate return lines are properly pitched?
  • Which statement best describes a boiler trip on loss of flame and a typical troubleshooting approach?
  • In cooling tower operation, increasing the inlet water temperature while holding air conditions constant will
  • Explain stack draft and how it is controlled in a boiler system.
  • Which of the following is a high-level step to improve boiler plant energy efficiency?
  • A closed cycle gas turbine: which statement is true?
  • Steam turbine governors primarily
  • In a gas turbine cycle, the regenerator's role is to
  • Which shaft sealing material is commonly used in small steam turbines?
  • A simple gas turbine lacks which component?
  • The output power of a gas turbine mainly depends upon which factor?
  • What is the purpose of insulation on boiler and piping?
  • What is the primary purpose of condensate return lines in a steam system?
  • The combustion chamber of a gas turbine:
  • In an impulse turbine, energy transfer occurs primarily due to
  • Which statement about the ignition mechanism in a diesel engine is correct?
  • What is the role of a deaerator in feedwater treatment?
  • A simple gas turbine is one without reheaters or regenerators.
  • What is a recommended practice to prevent thermal shock in boilers?
  • What is the primary purpose of a spark plug in a gasoline engine?
  • What is a steam trap and why is it essential in steam systems?
  • Outline a typical shutdown sequence for a fired boiler.
  • Four-stroke cycle engine valves are
  • The part of a camshaft that converts rotary motion to reciprocating motion is called
  • Which statement correctly describes how energy input and efficiency relate in a boiler?
  • Which of the following is NOT a common cause of boiler carryover?
  • Which component is primarily responsible for atomizing diesel fuel before it enters the combustion chamber?
  • A two-cycle gasoline engine is simpler than a four-cycle engine in construction.
  • Sealing between piston rings and the cylinder wall may be the result of which condition?
  • Diesel engines require:
  • Which statement is true about the two-shaft gas turbine architecture?
  • Water is removed from the air stream leaving a cooling tower by using which device?
  • The shafts of high-output, high-temperature steam turbines are typically sealed using which method?
  • What is the primary function of the turbine overspeed trip?
  • What is a pressure relief device and when should it operate?
  • The shrouding on the blades of a steam turbine primarily serves to
  • In a turbine blade assembly, shrouding influences steam flow by which of the following?
  • Define blowdown rate and factors that influence its value.
  • Which component in a gas turbine system is responsible for burning the fuel?
  • How does stack height influence emissions dispersion and safety?
  • A counter-flow cooling tower generally requires less floor space than a crossflow cooling tower. Which statement best describes this comparison?
  • When the steam pressure drop occurs only in the stationary steam passages, the turbine is known as:
  • In theory, impulse turbines have which characteristic regarding pressure on moving blades?
  • In a two-shaft gas turbine, the load turbine is located relative to the compressor turbine?
  • What does P&ID stand for, and what does it primarily show in a plant for safe operation and maintenance?
  • Cylinder scavenging is best described as
  • How is diesel engine fuel delivered to the combustion chamber?
  • In a water-tube boiler, what is the function of the steam drum and the mud drum?
  • Which component is necessary for diesel engines to inject fuel into the combustion chamber?
  • What is burner management (flame safeguard) and why is it critical during start-up?
  • What determines the saturation temperature of steam?
  • The shafts of high output, high temperature steam turbines are usually sealed using:
  • The low installation cost of a gas turbine is primarily due to which factor?
  • Biological attack on cooling tower wood affects the
  • The hand wheel used to adjust the turbine speed on the governor is known as the:
  • What is a major difficulty encountered with a two-stroke cycle engine?
  • What is the primary purpose of boiler blowdown?
  • In a diesel engine, an injection nozzle is used for _________.
  • Raising the air temperature entering a gas turbine compressor primarily causes the turbine's output power to do what?
  • Which lubrication method is correct for large four-cycle engines?
  • In a reaction turbine, what happens to the steam as it passes through moving blades?
  • Which step is part of a safe startup sequence for a fired boiler?
  • The purpose of a regenerator is to:
  • Turbines often have segmental carbon ring sealing glands that are held in place by
  • In a fire-tube boiler, where are the hot combustion gases located?
  • A cold weather cooling tower bypass valve should not be fully closed until the temperature reaches:
  • The rotating passages of a reaction turbine are mounted on which component?
  • How do safety relief valves and system piping work together to prevent overpressure?
  • The purpose of turbine glands is to prevent:
  • An engine that has one power stroke every two crankshaft revolutions is a:
  • The rate of heat transfer in any cooling tower system depends on the:
  • What is the purpose of a boiler safety valve and how is it tested?
  • Differentiate continuous blowdown from manual blowdown and explain why each is used?
  • The hand wheel used to adjust turbine speed on the governor is called the:
  • Diesel engine governing is accomplished by:
  • A gas turbine is most efficient when
  • Which practice is essential for safe boiler room operations?
  • A gas turbine: Which statement best describes how output responds to intake air density?
  • Which of the following is not a type of condenser used in a steam power plant?
  • The injection pump of a diesel engine is driven by:
  • Clean air flows into a gas turbine regenerator from:
  • In a four-stroke gasoline engine, which stroke begins the cycle?
  • Large four-cycle engines are usually lubricated with
  • In impulse turbines, rotating blades are called Buckets.
  • Excessive wind velocity in a natural draft cooling tower may cause?
  • A two-cycle gasoline engine is characterized by which statement?
  • What gases are typically measured in flue gas analysis and why?
  • Which statement differentiates continuous and manual blowdown?
  • Which condenser type is not used in steam power plants?
  • What is the purpose of high-low water alarms?
  • A gas turbine must be rotated at _______ speed before ignition begins.
  • One complete movement of the piston in one direction requires ____________ of the engine crankshaft:
  • What is boiler carryover and what are common causes?
  • In a water-tube boiler, where is the water located?
  • What is the main purpose of interlocks between drum level control and feedwater pump operation?
  • How do fire-tube boilers differ from water-tube boilers, and what is a typical application for each?
  • Which of the following comes earliest in the start-up sequence of a steam turbine?
  • Natural draft cooling towers operate most effectively in large open spaces and:
  • Which statement about drift eliminators is true?
  • An advantage of gas turbines over other types of prime movers, is that gas turbines:
  • What is the purpose of purging during a boiler shutdown?
  • Which statement correctly describes a two-shaft gas turbine?
  • Which statement describes the function of the flame safeguard system in a boiler?
  • What happens if condensate return is not functioning?
  • Using a compressed air starting motor is a common method of starting
  • Which statement best describes the gas turbine's suitability as a prime mover?
  • The primary function of steam turbine governors is to
  • Which treatment step most directly reduces corrosion risk in boilers?
  • What is phosphate treatment in boiler water and what is its purpose?
  • How is a boiler safety valve typically tested to ensure proper operation?
  • A gas turbine compressor:
  • What is the primary reason for oxygen removal in feedwater treatment?
  • Which device helps remove drift from a cooling tower's exhaust air?
  • Which statement correctly distinguishes psig and psia?
  • What is the purpose of tying boiler drum level control to feedwater pump start/stop interlocks?
  • What is a true statement about a gas turbine starting device?
  • Which term specifically excludes the latent heat of vaporization from the energy content?
  • Which statement best describes a boiler safety device?
  • In a reaction turbine, which component supports the rotating passages?
  • How does drum level control maintain safe boiler operation?
  • A starting device for a gas turbine
  • During the startup sequence of a steam turbine, which action is performed first?
  • In a four-stroke engine, how many crankshaft revolutions are required for a complete intake, compression, power, and exhaust cycle?
  • What measurement devices are commonly used for boiler water level indication and what failure risks exist?
  • Which statement about steam dryness and turbine erosion is correct?
  • What is the purpose of the mud drum in a water-tube boiler?
  • Which device prevents boiler operation when water level is too low?
  • In impulse turbine operation, energy transfer to the blades is primarily achieved by which phenomenon?
  • The injection pump of a diesel engine is driven by which component?
  • Rotating blades or "________" form the steam flow passages in impulse turbines.
  • What is the purpose of insulation in boiler systems?
  • Internal combustion engines used to drive gas compression machinery burning natural gas typically operate on which cycle?
  • Which starting method is commonly used to start large stationary diesel engines?
  • Which components are typically involved in drum level control?
  • Shaft sealing of small steam turbines is typically accomplished with which option?
  • During a single rotation of a 4-stroke cycle gasoline engine crankshaft, the engine undergoes?
  • Starting a diesel engine with injected compressed air uses approximately which pressure?
  • Natural draft cooling towers are divided into which categories?
  • If boiler drum level is too high, what is the most likely risk?
  • Which statement describes the startup capability of gas turbines?
  • Compression ignition engines: which statement is true?
  • What is the role of refractory in a boiler furnace?
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