PRIME MOVERS FINAL EXAM ACTUAL QUESTIONS AND ANSWERS 2024 UPDATE;(ALREADY GRADED A+)FULL COMPLETE TEST SOLVED 100%

PRIME MOVERS FINAL EXAM ACTUAL QUESTIONS AND ANSWERS 2024 UPDATE;(ALREADY GRADED A+)FULL COMPLETE TEST SOLVED 100% Despite their size and complexity, steam plants are widely used because: a) of their low emissions of pollutants b) they are easily located in an urban environment c) they can be run by untrained personnel d) they require minimal amounts of water e) they can burn solid fuels such as coal and wood. Ans- E Connecting Rods on a steam engine: a) convert reciprocating motion to rotary motion b) are used to move the slide valve c) are only needed on vertical engines d) are used to connect the piston to the slide valve e) connects the inlet valve to the discharge valve Ans- A A "heat engine" is an operating cycle that uses a working fluid to convert: a) thermal energy to chemical energy b) chemical energy to mechanical energy c) thermal energy to electrical energy d) mechanical energy to electrical energy e) thermal energy to mechanical energy Ans- E A single device which converts a natural source of energy to mechanical motion is a/an: a) prime mover b) heat engine c) electric motor d) steam plant e) alternator Ans- A A gasoline engine is a "heat engine". What is its working fluid? a) glycol b) gasoline c) air d) glycol and water e) gasoline and air Ans- E What is the main advantage of using the expansive properties of steam? a) reliability b) speed of response c) economy d) lower steam pressures can be used e) superheated steam can be used Ans- C Thinking of a steam engine and its construction, what does "eccentric" mean? a) strange b) out-of-center c) economical d) redundant e) bi-directional Ans- B On a steam engine, what is the purpose of a "flywheel" 1. it prevents an over speed condition 2. It dampens speed fluctuations 3. It allows the direction of rotation to be changed 4. It carries the engine over dead center. a) 1, 2 b) 1, 3 c) 1, 4 d) 2, 3 e) 2, 4 Ans- E Advantages of a steam engine include: 1. It is possible to change the direction of rotation without the use of gearing 2. they have a high rotational speed 3. they are simple and rugged 4. they have a slow rotational speed without the need for reduction gearing a) 1, 2 b) 3, 4 c) 1, 2, 3 d) 1, 3, 4 e) 2, 3, 4 Ans- D A prime mover is a) an electric motor b) a steam turbine c) a centrifugal pump d) an air compressor e) a boiler Ans- B Large power production plants tend to be of the thermal type because they can burn solid fuels and: a) they are the least expensive to build b) the noise level is much less than internal combustion engines c) the heat cycle they use is the most efficient d) solid fuels are the most plentiful and cheapest e) require the least amount of manpower Ans- C A steam engine will have the steam supply to the cylinder shut off once the piston has travelled a) 25 to 35% of its stroke b) 75 to 90% of its stroke c) 15 to 20% of its stroke d) 55 to 65% of its stroke e) 90 to 95% of its stroke Ans- A The reciprocating motion of a steam engine is converted to rotary motion a) at the end of the piston stroke b) in the steam cylinder c) via the valve eccentric d) at the crankshaft e) via the valve gear Ans- D The crosshead of a steam engine a) imparts angular motion to the piston rod b) is where linear motion becomes angular motion c) imparts linear motion to the piston rod d) does not require any lubrication e) never requires any special bearing material Ans- B A steam engine piston a) moves fastest at the end of its stroke b) can never have steam applied to either side c) is lubricated from the crankcase oil by splash method d) moves fastest at the mid point [beginning?] of its stroke e) never requires lubrication Ans- D A routine inspection of an operating steam engine should cover first and foremost a) lubricators b) drive belts c) engine speed d) steam temperature e) steam quality Ans- A Whenever feasibly possible, when checking bearings on running pieces of equipment it is wise to a) check the oil quality leaving each b) check the oil quantity leaving each c) get accustomed to normal running temperature and vibration by feel d) smell the normal odours of the running bearing e) observe the temperature on a thermometer Ans- C One of the first ways to detect a fault in a reciprocating engine is a) by sound b) temperature indication c) performance efficiency d) by oil consumption e) by smell Ans- A The slide valve of a steam engine is designed to a) allow the piston to slide more freely b) drain the condensate from the cylinder during warm-up c) provide lubrication for the steam engine d) provide for the steam to enter and leave the cylinder e) prevent the engine from over speeding Ans- D Chapter 69 Steam Turbines I Ans- The stationary passages of a reaction turbine are called the: a) shaft b) rotor c) shroud ring d) fixed blades e) diaphragms Ans- D Steam turbine governors a) prevent the turbine from over speeding b) regulate the speed of the turbine automatically c) should be checked annually by the boiler inspector d) are driven by the generator shaft e) are not required for reaction turbines Ans- B In theory, impulse turbines: a) have a velocity drop through the nozzle b) have no pressure drop through the moving blades c) use only low-pressure steam d) develop the most torque of all turbines e) require large thrust bearings Ans- B For what purpose is lubricating oil required on a turbine, besides lubrication? a) to seal the shafts b) to maintain vibration free operation c) to carry heat away from the bearings d) to eliminate friction e) to reduce corrosion on the turbine blading Ans- C Reaction turbines a) have bucket shaped blades b) have a pressure drop through moving and stationary blades c) are used for high pressures only d) have a pressure drop in the moving blades only e) have little axial thrust Ans- B How many basic types of turbines are there a) 1 b) 2 c) 3 d) 4 e) 5 Ans- B What is the purpose of the nozzle in a turbine? a) to create a pressure rise b) to lower steam velocities c) to increase steam velocities d) to direct the steam onto the shaft e) to create kinetic momentum Ans- C Impulse turbines: a) have a velocity drop through the nozzle b) have no pressure drop through the moving blades c) use low pressure steam only d) are of the single stage design only e) require large thrust bearings Ans- B What are the two purposes of a turbine condenser? 1. to heat the condensate 2. to increase efficiency 3. to provide a pure source of boiler feedwater 4. to create a vacuum a) 1, 2 b) 2, 4 c) 1, 3 d) 2, 3 e) 1, 4 Ans- D In a reaction turbine the steam pressure ____ in passing through moving blades, as well as stationary nozzles or blades. a) increases b) drops c) recirculates d) accelerates e) modulates Ans- B A steam turbine's exhaust can often supply a process with steam because a) processes always require a lower steam pressure b) processes never require the high steam temperatures turbines do c) turbine exhaust steam is always dry and saturated d) it is free of oil e) the steam will be at a temperature above the initial temperature Ans- D The exhaust steam from a steam turbine is more acceptable for process than the exhaust from a steam engine because a) it is much hotter b) it is easily controlled c) it is free of oil d) it is free of moisture e) it contains more condensate Ans- C The exhaust steam from a condensing steam turbine ____________ than the exhaust from a steam engine: a) is drier b) has more vapour c) is more contaminated d) is hotter e) has more moisture Ans- E Turbines often have segmental carbon ring sealing glands which are held in place by a) labyrinths b) shrouding c) drive screws d) garter springs e) thrust runners Ans- D A steam turbine should trip or shut down when normal operating speed is exceeded by a) 250 RPM b) 3to5% c) 50 RPM d) 10 to 15% e) 25 RPM Ans- D Condensing turbines a) are always impulse turbines b) will have a vacuum in the last row of rotating blades c) will use the condensate for heating d) are very small units e) cannot have counterflow stages Ans- B Which turbine uses a condenser? a) back pressure turbine b) a turbine exhausting to a vacuum c) a bleeder turbine exhausting at atmospheric pressure d) a non-condensing extraction turbine e) a turbine exhausting to atmosphere Ans- B The shrouding installed on the blading of a steam turbine serves to: a) cool the blade tips b) expand the steam c) stop the steam flow d) heat the steam e) confine the steam to the blades Ans- E The turbine overspeed trip: 1. prevents the turbine from vibrating 2. prevents the turbine exceeding the maximum rated speed 3. is operated by a spring loaded pin in the rotating blades 4. will close the steam stop valve 5. should be tested before the turbine is placed in service a) 2,4,5 b) 2,3,4,5 c) 1,2,4 d) 3,4,5 e) 4,5 Ans- A The overspeed trip of a steam turbine a) operates on turbine vibrations due to high speed b) is installed on all turbines c) can be adjusted according to the load demand d) is regulated by exhaust pressure e) sheds the load in the event of high pressure Ans- B Turbine overspeed trip a) prevents the turbine from vibrating b) will close the steam stop valve to the turbine c) is operated by a spring loaded pin in the rotating blades d) supplies the operator with rpm indications e) reduces the turbine speed by increasing the back pressure Ans- B Steam turbine lubricating oil a) is not required for small impulse turbines b) must be changed every four months c) lubricates the blades d) can be used to operate the turbine governor e) should be preheated before use Ans- D The purpose of turbine glands is to prevent a) water from entering the turbine b) steam from entering the turbine c) steam escaping from the turbine d) steam from entering the lubrication system e) oil from entering the turbine Ans- C Shaft sealing in high output turbines is done with a) water seals b) mechanical seals c) wear rings d) packing glands e) labyrinth seals Ans- E When the steam pressure drop occurs in only the stationary members or components of a turbine, the turbine is known as a) a single stage unit b) an impulse unit c) a reaction unit d) a Parsons unit e) a cross compound reaction unit Ans- B A large reaction turbine will have a) no thrust bearings b) steam pressure dropping in only the moving sections c) blades which are basically symmetrical in cross-section d) never more than 5 stages e) steam pressure dropping through moving and stationary sections Ans- E Turbine speed can be "fine tuned" with a device which will be limited to about 10% over the rated speed. This device is the a) governor valve b) overspeed governor c) sentinel valve d) hand speed control e) overspeed trip Ans- D Turbine thrust bearings are fixed to the casing and prevent axial movement of the spindle by contacting a component on the shaft known as a a) shaft sleeve b) labyrinth c) collar d) shroud e) diaphragm Ans- C Shaft sealing carbon glands are a) lubricated by the main oil pump b) limited to a temperature of 250 degrees C c) replaced monthly due to erosion d) self-lubricating e) metal sprayed components Ans- D The great majority of steam turbine governing systems utilize the a) hydraulic system principle b) pneumatic system principle c) mechanical centrifugal principle d) lever principle e) bimetal expansion principle Ans- C Reaction turbines a) have bucket shaped blades b) have a pressure drop through the moving and stationary blades c) are used for high pressures only d) have a pressure drop in the moving blades only e) have little axial thrust Ans- B Reaction turbines a) have all of the steam pressure drop take place in the stationary nozzle b) have a velocity increase in the fixed blading c) are used for higher speed only d) have a velocity decrease through the fixed blading e) require little blade sealing Ans- B In an impulse turbine a) the steam flow is reduced through the nozzles b) the steam pressure is reduced in the nozzles c) the steam pressure will drop across the blades d) the steam velocity is increased through the blades e) the exhaust steam is directed back to the boiler Ans- B The steam turbine that has a pressure drop across every set of blades is the __________ turbine. a) double-stage impulse b) single-stage impulse c) topping d) back pressure e) reaction Ans- E When starting a steam turbine it is customary practice to a) analyze the oil for water prior to rolling b) turn on all cooling water systems first c) place the speed control system in service once the unit is rolling d) test the overspeed trip as soon as running speed is attained e) stop the auxiliary oil pump as soon as steam begins to turn the unit Ans- D Condenser Questions Ans- If the cooling water for a condenser, taken from a cooling tower is high in dissolved oxygen, the ability of the condenser to act as a deaerator is a) directly proportional to the level of dissolved oxygen b) not impeded c) inversely proportional to the level of dissolved oxygen d) impeded e) reduced Ans- B The difference between a jet condenser and a barometric jet condenser is: a) there are no pumps in a barometric jet condenser b) the jet condenser operates at a pressure above barometric c) in a barometric condenser, the water is pumped out of the unit d) in a barometric condenser, the water flows out by gravity e) the length of the barometric leg Ans- D .......................