National Maritime Center

Transcription

1 U.S.C.G. Merchant Marine Exam (Sample Examination) Page 1 of 33

2 U.S.C.G. Merchant Marine Exam Illustrations: 16 Choose the best answer to the following Multiple Choice Questions. 1. Traditionally, which of the listed refrigerants has been more suitable than the others for use in a centrifugal refrigeration compressor? (A) R-11 o (B) R-12 o (C) Ammonia o (D) Carbon dioxide 2. Why can CFC or HCFC refrigerants leaking into a confined space or in limited surroundings cause suffocation? (A) Refrigerants are heavier than air and displace oxygen. o (B) Refrigerants lighter than air will rise. o (C) Refrigerants obnoxious odor prevents breathing. o (D) Refrigerants contain an acidic substance. 3. A magnetic strainer is primarily used in diesel engine reduction gear oil systems to remove small particles of. (A) ferrous materials o (B) Babbitt o (C) copper o (D) acidic materials 4. The process of supplying a diesel engine cylinder with air at a pressure greater than atmospheric is called. o (A) engine displacement o (B) super-aspirating o (C) air injection (D) supercharging If choice D is selected set score to 1. Page 2 of 33

3 U.S.C.G. Merchant Marine Exam Illustrations: Steam condensed in the air ejector intercondenser, drains to the. o (A) atmospheric drain tank o (B) vent condenser drain tank (C) main condenser through the loop seal o (D) after condenser drain tank If choice C is selected set score to Unless the system is designed for such operation, two compressors should not be operated in parallel in a refrigeration system for what reason? (A) lubricating oil may be transferred from one compressor to the other o (B) condenser pressure will be too high causing condenser failure o (C) operation of two compressors will overload the expansion valves o (D) the evaporators would fail due to excessively low suction pressure 7. Which of the following reasons represents why the designed compression ratio of a gasoline engine is lower than that of a diesel engine? o (A) Compression must be low for smooth operation. (B) The heat of compression is not used as an ignition source of the fuel. o (C) Compression must be low to have effective pre-ignition. o (D) Compression must be low for effective spark ignition. If choice B is selected set score to What is the purpose of the items labeled "moving blades" located on the illustrated steam turbine? Illustration SE-0003 (A) Convert the kinetic energy of the steam exiting the nozzle to mechanical energy of rotation. o (B) Convert the potential energy of the steam exiting the nozzle to mechanical energy of rotation. o (C) Change the direction of travel of the steam. o (D) Convert the kinetic energy of the steam exiting the nozzle to potential energy. 9. The boiler shown in the illustration would be classed as. Illustration MO-0064 o (A) forced circulation, coil-type o (B) two-pass, water-tube o (C) two-pass, scotch marine (D) single-pass, fire-tube, scotch marine If choice D is selected set score to 1. Page 3 of 33

4 U.S.C.G. Merchant Marine Exam Illustrations: Personnel servicing refrigeration systems and subject to the exposure to commonly used refrigerants should wear what type of personal protective equipment? o (A) an all purpose gas mask (B) goggles and gloves o (C) rubber soled shoes o (D) a respirator If choice B is selected set score to Which of the following methods is normally used to lubricate bearings in a small high-speed diesel engine? o (A) Splash lubrication (B) Pressure lubrication o (C) Sight feed lubricators o (D) Mechanical lubricators If choice B is selected set score to In a coil-type forced circulation auxiliary water-tube boiler,. (A) steam demand response is comparatively rapid o (B) steam is recirculated through heating coils in the boiler o (C) unevaporated feedwater is discharged through the skim tube o (D) steam demand response is slow 13. The component shown in the illustration, labeled "IV", is the. Illustration SE-0013 o (A) first reduction gear o (B) low-speed pinion o (C) high-speed pinion (D) bull gear If choice D is selected set score to To minimize corrosion, fuel oil strainer disks, spacers and scraper blades are made of. o (A) brass o (B) copper o (C) iron (D) monel metal or stainless steel If choice D is selected set score to 1. Page 4 of 33

5 U.S.C.G. Merchant Marine Exam Illustrations: Makeup feedwater is brought into an operating closed feed system via the. o (A) auxiliary feed pump o (B) main feed pump (C) condenser vacuum drag line o (D) feed booster pump If choice C is selected set score to According to the illustrated diagram, what statement is true concerning the operation of the main condenser hotwell level control device? Illustration SG-0010 o (A) The main condenser hotwell level is controlled by controlling the speed of the main condensate pump. (B) The main condenser hotwell level is controlled by throttling the flow in a recirculating line teed off the main condensate pump discharge line and leading back the main condenser. o (C) The main condenser hotwell level is controlled by throttling the main condensate pump discharge to the main air ejector. o (D) The main condenser hotwell level is controlled by throttling the main condensate pump suction from the main condenser hotwell. If choice B is selected set score to The items labeled "D" in the illustration are the. Illustration SG-0025 o (A) high-pressure drain connections o (B) low-pressure steam supply connections (C) low-pressure drain connections o (D) low-pressure vent connections If choice C is selected set score to In a diesel engine jacket water cooler, with sea water cooling the fresh water, the. (A) jacket water pressure should always be greater than the sea water pressure o (B) jacket water pressure must always be less than the sea water pressure o (C) jacket water temperature must always be less than 60 F o (D) sea water temperature must never be warmer than 40 F 19. In order to take suction on the lube oil drain tank cofferdam with the bilge pump shown in the illustration, how many suction side valves must be open? Illustration GS-0042 o (A) One (B) Two o (C) Three o (D) Four If choice B is selected set score to 1. Page 5 of 33

6 U.S.C.G. Merchant Marine Exam Illustrations: Which of the following descriptions best identifies the operating principal of a flash type evaporator? o (A) Sea water is heated to boiling temperature while under a vacuum. o (B) Sea water is passed over heated plates in a thin film. (C) Heated sea water is injected into a vacuum chamber. o (D) Sea water is forced through a heated eductor. If choice C is selected set score to If a diesel engine has been stopped because of piston seizure due to severe overheating, the crankcase. (A) inspection covers should not be opened until the engine has cooled o (B) scavenge pump should be immediately secured to prevent loss of lube oil o (C) ventilation system should be continued in operation for one hour for cooling o (D) explosion covers should be opened slightly to provide extra ventilation 22. If manual control of the water level in a steaming boiler is required, the proper method of control is with the auxiliary feed. o (A) pump pressure control (B) stop-check valve o (C) stop valve o (D) pump speed control If choice B is selected set score to For the typical marine turbocharged main propulsion diesel engine, where is the usual location for the air intake filter and silencer? o (A) The air intake filter/silencer usually is local to the engine and surrounds the circumference of the turbocharger turbine inlet. o (B) The air intake filter/silencer usually is remote from the engine and is mounted in a protected area above the weather deck. (C) The air intake filter/silencer usually is local to the engine and surrounds the circumference of the turbocharger blower/compressor inlet. o (D) The air intake filter/silencer usually is remote from the engine, but still in the engine room mounted on a convenient bulkhead. If choice C is selected set score to 1. Page 6 of 33

7 U.S.C.G. Merchant Marine Exam Illustrations: As shown in the illustrated D type single furnace boiler, what does item "E" represent? Illustration SG-0008 o (A) Riser tubes (B) Downcomer tubes o (C) Upcomer tubes o (D) Support tubes If choice B is selected set score to Which of the following desalination plants will always require a sterilizer when providing water to a potable water system? o (A) Submerged tube type unit o (B) Titanium plate type unit (C) Reverse osmosis type unit o (D) Multi-stage flash type unit If choice C is selected set score to What type of bearing is shown in the illustration? Illustration SE-0012 o (A) Plain thrust bearing (B) Pivoted shoe thrust bearing o (C) Pivoted shoe journal bearing o (D) Tilting pad journal bearing If choice B is selected set score to According to the illustrated diagram, what is the correct sequential order of heat exchangers that the main condensate pump pumps condensate through? Illustration SG-0010 o (A) Main air ejector condenser, deaerating feed tank, first stage feed heater, gland exhaust condenser. (B) Main air ejector condenser, gland exhaust condenser, first stage feed heater, deaerating feed tank. o (C) Main air ejector condenser, first stage feed heater, gland exhaust condenser, deaerating feed tank. o (D) Main air ejector condenser, deaerating feed tank, gland exhaust condenser, first stage feed heater. If choice B is selected set score to 1. Page 7 of 33

8 U.S.C.G. Merchant Marine Exam Illustrations: The primary function of the device illustrated is to. Illustration GS-0029 (A) remove all but the frictional load of an air compressor at start-up o (B) precharge the cylinders of an air compressor prior to the start-up of the unit o (C) open the discharge valves during the compressors' operation to supply compressed air o (D) intensify the pressure developed by an air compressor during its normal running operation 29. The power consumed during the scavenging process of a diesel engine is known as the. o (A) compression loss o (B) valve loss o (C) back pressure loss (D) pumping loss If choice D is selected set score to The maximum pressure developed by a waste heat boiler is determined by the main engine exhaust. o (A) gas composition (B) gas temperature o (C) pressure o (D) timing If choice B is selected set score to According to the illustrated diesel engine fuel treatment and fuel service systems schematic, what is the purpose of the device labeled "viscosimeter"? Illustration MO-0077 o (A) It controls the speed of the booster pump for the purpose of controlling the fuel oil viscosity supplied to the fuel injection pumps of the main engine. o (B) It measures the viscosity of the fuel oil being delivered to the fuel injection pumps of the main engine. It is used for indication only and not control. (C) It controls the steam flow through the final heater for the purpose of controlling the fuel oil viscosity supplied to the fuel injection pumps of the main engine. o (D) It controls the position of the three-way mixing valve for the purpose of controlling the fuel oil viscosity supplied to the fuel injection pumps of the main engine. If choice C is selected set score to 1. Page 8 of 33

9 U.S.C.G. Merchant Marine Exam Illustrations: Diesel engine jacket water is used in the fresh water distillation process as the. o (A) primary means of producing a vacuum within the distiller (B) means of heating the feedwater o (C) coolant for the brine cooler o (D) coolant for the distillate If choice B is selected set score to Which of the tanks, shown in the illustration, supplies fuel to the emergency generator? Illustration MO-0058 (A) Light fuel oil service tank o (B) Light fuel oil settling tank o (C) Light fuel oil boiler tank o (D) Light fuel oil booster tank 34. Why are two fuel oil heaters "E" provided in the fuel oil system shown in the illustration? Illustration SG-0009 o (A) To allow fuel of different temperatures to be provided to each boiler. o (B) Two heaters are necessary when both boilers steam at full load. (C) To provide a backup in case one of the heaters becomes inoperable. o (D) Each heater supplies fuel to a different boiler. If choice C is selected set score to By which of the listed methods may heat be transferred from one body to another? o (A) Convection o (B) Conduction o (C) Radiation (D) All of the above If choice D is selected set score to 1. Page 9 of 33

10 U.S.C.G. Merchant Marine Exam Illustrations: What statement is true concerning the charge air system of a modern turbocharged slow-speed twostroke cycle diesel engine? o (A) A mechanically driven auxiliary blower is usually provided because the turbocharger cannot provide enough air at low engine speeds and loads. (B) An electrically driven auxiliary blower is usually provided because the turbocharger cannot provide enough air at low engine speeds and loads. o (C) An electrically driven auxiliary blower is usually provided because the turbocharger cannot provide enough air at high engine speeds and loads. o (D) A mechanically driven auxiliary blower is usually provided because the turbocharger cannot provide enough air at high engine speeds and loads. If choice B is selected set score to In a two-stage flash evaporator, the sea water feed temperature is increased as it passes through the. o (A) second stage distilling condenser o (B) salt water feed heater o (C) first stage distilling condenser (D) all of the above If choice D is selected set score to The load is always placed on the lower half of the main bearings in a. (A) two-stroke cycle engine o (B) four-stroke cycle engine o (C) reverse cycle engine o (D) double acting engine 39. Which of the routine maintenance procedures listed is required for starting air receivers? (A) Frequent draining of accumulated moisture. o (B) Frequent testing of relief valves. o (C) A close watch on temperature to prevent fluctuations in pressure. o (D) Frequent cleaning to remove oil and foreign matter. 40. Rudder position is shown on the bridge by the. (A) rudder angle indicator o (B) follow-up gear o (C) telemotor position o (D) Rapson slide indicator Page 10 of 33

11 U.S.C.G. Merchant Marine Exam Illustrations: The process of boiling sea water in order to separate it into fresh water vapor and brine is usually defined as. o (A) dehydration o (B) dissolution o (C) condensation (D) evaporation If choice D is selected set score to Corrosion inhibitors and/or soluble oils are added to diesel engine cooling systems to. o (A) reduce the cooling water temperature o (B) increase cooling water hardness (C) form a protective film on metal surfaces o (D) maintain low ph in the cooling water If choice C is selected set score to The DC heater automatic level dump valve is used to. (A) drain excess feedwater to the distilled water tank o (B) divert the flow of condensate from the first stage heater to the vent condenser o (C) recirculate condensate to the atmospheric drain tank o (D) maintain a proper condensate level in the condenser hotwell 44. The cylinders and intercoolers of most low-pressure air compressor's are cooled by. (A) air o (B) CO 2 o (C) oil o (D) water Page 11 of 33

12 U.S.C.G. Merchant Marine Exam Illustrations: If a steam propulsion plant is provided with two main propulsion boilers, two fuel oil service heaters, two fuel oil service pumps, and two fuel oil settling tanks, what is the capacity of each fuel oil service heater? (A) Each heater has the capacity to supply heated fuel to both boilers under full load with one service pump running. o (B) Each heater has the capacity to supply heated fuel to both boilers under full load with both service pumps running. o (C) Each heater has the capacity to supply heated fuel to just one boiler under full load with both service pumps running. o (D) Each heater has the capacity to supply heated fuel to just one boiler under full load with one service pump running. 46. One of the consequences in continuing to operate a centrifugal bilge pump with the discharge valve closed, is that the. o (A) motor overload will open o (B) motor will overheat o (C) relief valve will open (D) pump will overheat If choice D is selected set score to In a diesel engine exhaust system, the cooling of the exhaust gases below their dew point, will result in. o (A) increased engine back pressure (B) sulfuric acid corrosion o (C) surface pitting of the turbocharger compressor blades o (D) moisture impingement on the turbocharger compressor blading If choice B is selected set score to The steam drum in a D-type marine boiler. o (A) maintains circulation by forcing steam bubbles downward in the generating tubes o (B) acts as a receptacle for heavy suspended solids in boiler feedwater o (C) supports the superheater tube bank (D) provides a space for moisture to separate from the steam If choice D is selected set score to 1. Page 12 of 33

13 U.S.C.G. Merchant Marine Exam Illustrations: When operating with the auxiliary feed line, feedwater flow is controlled. o (A) automatically by the economizer bypass o (B) manually by adjustment of the auxiliary feedwater regulator spring setting (C) manually by throttling the auxiliary feed stop-check valve o (D) automatically by the main feedwater regulator If choice C is selected set score to Greases used for most marine applications would use what thickening base? o (A) Calcium-based o (B) Lime-based o (C) Aluminum-based (D) Lithium-based If choice D is selected set score to When starting a turbo-generator in an automated plant, you must provide lube oil pressure to the unit by means of. (A) the hand-operated or auxiliary lube oil pump o (B) a line from the other generator o (C) a line from the gravity tank o (D) the main lube oil pump 52. If an air compressor is used to supply air primarily to the combustion control system and other pneumatic controllers, the entire system is known as the. (A) control air system o (B) ships service air system o (C) forced draft air system o (D) supply air system 53. What is the name of the device pictured in the illustration? Illustration SE-0001 (A) Gear type flexible coupling o (B) Solid coupling o (C) Quill shaft o (D) Hydraulic clutch Page 13 of 33

14 U.S.C.G. Merchant Marine Exam Illustrations: The device shown in the illustration is a. Illustration GS-0155 o (A) relief valve (B) flushometer valve o (C) hydrokineter o (D) back pressure regulator If choice B is selected set score to The primary reason low-pressure evaporators produce distillate more efficiently, and with less scale formation, than high-pressure evaporators is. (A) evaporation is accomplished in a vacuum o (B) evaporation in a submerged medium produces more distillate o (C) due to the higher temperature of the incoming feed o (D) due to the latent heat of evaporation principle 56. Which of the statements represents a characteristic of the thrust collar in a Kingsbury thrust bearing? (A) It turns with the shaft and the pivot shoes do not rotate. o (B) It is stationary and the shoes turn with the shaft. o (C) It is turned by the base ring of the bearing. o (D) It is held in position by the bearing base ring. 57. To prevent pulsations from developing in the boiler feedwater lines, the discharge side of a reciprocating feed pump is equipped with a/an. o (A) feedwater regulator (B) air chamber o (C) reed valve o (D) relief valve If choice B is selected set score to On a main propulsion turbine set of a merchant ship, where is the astern staging generally located? (A) Within the low-pressure turbine o (B) Within the intermediate pressure turbine o (C) Within a separate astern turbine o (D) Within the high-pressure turbine Page 14 of 33

15 U.S.C.G. Merchant Marine Exam Illustrations: As found in a reduction gear drive system, thrust bearings serve to. o (A) hold the main engine in place o (B) increase the shaft speed o (C) limit the radial movement of the shaft (D) transmit the force produced by the propeller to the structure of the ship If choice D is selected set score to Most type(s) of microbiological growths in fuel are. o (A) bacteria o (B) yeasts o (C) fungi (D) all of the above If choice D is selected set score to Which of the following precautions should be taken prior to lighting off a boiler? (A) Purge the furnace of combustible gases. o (B) Bottom blow the mud drum. o (C) Close the air register. o (D) Secure the main steam line drains. 62. The illustrated device is operated directly by. Illustration MO-0041 o (A) a rocker arm and push rod (B) fuel oil pressure o (C) cam action o (D) excessively high combustion pressure If choice B is selected set score to An increase in the air inlet manifold pressure of a diesel engine will result in a/an. o (A) decrease in maximum cylinder pressure o (B) increase in ignition lag (C) decrease in fuel consumption per horsepower-hour o (D) decrease in exhaust manifold pressure If choice C is selected set score to 1. Page 15 of 33

16 U.S.C.G. Merchant Marine Exam Illustrations: The amount of fuel delivered by a helical plunger fuel injection pump is controlled by. o (A) varying the pump discharge pressure o (B) varying the pump return pressure (C) rotation of the pump plunger o (D) rotation of the pump barrel If choice C is selected set score to A bearing using an oiling ring as a means of static oil feed must occasionally be serviced by removing the wear particles, grit, and moisture. How is this accomplished? o (A) Changing the filter element. o (B) Rotating the handle of the lube oil strainer. o (C) Draining the bottom of the strainer housing. (D) Draining the bottom of the bearing lube oil sump. If choice D is selected set score to In the illustrated schematic, the device used to replace the six-way valve, as found on many older type steering gears, is the component labeled as. Illustration GS-0123 (A) "A" o (B) "B" o (C) "F" o (D) "H" 67. An efficient seal is normally obtained between the upper and lower halves of a turbine casing by. o (A) asbestos gaskets o (B) flexible steel seal strips (C) precision metal-to-metal contact o (D) copper gaskets If choice C is selected set score to Air motors used for starting some auxiliary diesel engines are generally the type known as. (A) vane motors o (B) accumulator motors o (C) plunger motors o (D) gear motors Page 16 of 33

17 U.S.C.G. Merchant Marine Exam Illustrations: What statement is true concerning a propulsion steam turbine turning (jacking) gear? o (A) The jacking gear splined clutch is associated with the low-pressure turbine second reduction pinion. o (B) The jacking gear splined clutch is associated with the low-pressure turbine first reduction pinion. (C) The jacking gear splined clutch is associated with the high-pressure turbine first reduction pinion. o (D) The jacking gear splined clutch is associated with the high-pressure turbine second reduction pinion. If choice C is selected set score to Hydraulic couplings will transmit torque equal to the input torque by means of energy changes in a rotating vortex of liquid. For the vortices to form, there must be. (A) slip between the impeller and runner o (B) less than 2 percent slip between the impeller and runner o (C) axial thrust generated by the runner pinion shaft o (D) momentary torsional vibration transmitted by the driving impeller Page 17 of 33

18 GS /15/2015 Adapted for testing purposes only from KIAMEH, Power Plant Equipment Operation and Maintenance Guide Copyright 2012 by the McGraw Hill Companies, Inc. Further reproduction prohibited without permission Page 18 of 33

19 GS /11/2016 Adapted for testing purposes only from SEWARD, Marine Engineering Copyright 1968 by The Society of Naval Architects and Marine Engineers Further reproduction prohibited without permission Page 19 of 33

20 GS /9/2015 Adapted for testing purposes only from STUTMAN, Applied Marine Hydraulics Copyright 1988 by Cornell Maritime Press, Inc. Further reproduction prohibited without permission Page 20 of 33

21 GS /8/2016 Adapted for testing purposes only from Utilitiesman Basic, Volume 1 NAVEDTRA Further reproduction prohibited without permission Page 21 of 33

22 MO Adapted for testing purposes only from Souchotte and Smith, Marine Auxiliary Machinery. Copyright 1975 by Butterworth & Co (Publishers) Ltd. Page 22 of 33 Further reproduction prohibited without permission.

23 MO-0058 Adapted for testing purposes only from HARRINGTON, Marine Engineering. Copyright 1992 by The Society of Naval Architects and Marine Engineers. Further reproduction 4/21/2015 prohibited without permission. Page 23 of 33

24 MO /4/2015 Adapted for testing purposes only from SHIELDS, Boilers, Types, Characteristics, and Functions Copyright 1961 by McGraw-Hill, Inc. Further reproduction prohibited without permission. Page 24 of 33

25 MO /17/2017 Adapted for testing purposes only from HARRINGTON, Marine Engineering Copyright 1992 by The Society of Naval Architects and Marine Engineers Further reproduction prohibited without permission Page 25 of 33

26 SE /8/2016 Adapted for testing purposes only BLANK, Introduction to Naval Engineering, Second Edition Copyright 1985 by the United States Naval Institute Further reproduction prohibited without permission Page 26 of 33

27 SE /8/2016 Adapted for testing purposes only BLANK, Introduction to Naval Engineering, Second Edition Copyright 1985 by the United States Naval Institute Further reproduction prohibited without permission Page 27 of 33

28 SE /23/2016 Adapted for testing purposes only from Machinist s Mate 3 & 2 NAVEDTRA Further reproduction prohibited without permission Page 28 of 33

29 SE /27/2016 Adapted for testing purposes only from HARRINGTON, Marine Engineering Copyright 1992 by the Society of Naval Architects and Marine Engineers Further reproduction prohibited without permission Page 29 of 33

30 SG /7/2016 Adapted for testing purposes only from Principles of Naval Engineering NAVPERS B Further reproduction prohibited without permission Page 30 of 33

31 SG /8/2016 Adapted for testing purposes only HARRINGTON, Marine Engineering Copyright 1992 by The Society of Naval Architects and Marine Engineers Further reproduction prohibited without permission Page 31 of 33

32 SG /9/2016 Adapted for testing purposes only from HARRINGTON, Marine Engineering Copyright 1992 by the Society of Naval Architects and Marine Engineers Further reproduction prohibited without permission Page 32 of 33

33 SG /6/2016 Adapted for testing purposes only from SEWARD, Marine Engineering, Volume II Copyright 1944 by the Society of Naval Architects and Marine Engineers Further reproduction prohibited without permission Page 33 of 33