問題一覧
1
156. In a refrigeration system, the amount of superheat absorbed by the refrigerant is adjusted at the
•expansion valve
2
194. Which of the following is the reason for installing settling tanks in the fuel oil system?
•To heat, allowing sediments and water to settle down
3
189. The purpose of the six-way valve used in an electro-hydraulic steering system is to,
•redirect hydraulic fluid flow when changing over pumps
4
137. While overhauling a jerk-type pump and the pump plunger must be replaced. What other part must also be replaced?
•Pump barrel
5
138. During injection, the cam nose of the camshaft will push up the plunger of the pump, forcing the fuel to the ?
•fuel injector
6
125. Which of vthe following is the primary purpose of heaters in a pressurized fuel oil system?
•reduce the fuel viscosity for proper atomization
7
163. Parts of the pump used to maintain the alignment of the pump are ?
•bearings
8
197. Which of the items listed below is normally describe a ventilating fan?
•Axial flow
9
106. The temperature of the refrigerant in the evaporator coil defends mostly upon the
•refrigerant pressure in the evaporator
10
152. Gas turbine uses a cycle that includes intake, compression, expansion and exhaust. Which of the following are you going to use to best explain the complete cycle.
•Pressure volume diagram
11
141. The greatest decrease in the temperature of a refrigerant is at the
•expansion valve.
12
149. Some engines are using auxiliary electrically driven blowers which is continuously running during maneuvering and automatically cut-off if the scavenge air pressure reaches load.
•50%
13
108. A distorted spray pattern from a fuel injector can cause a diesel engine to have ?
•less power output
14
118. Cylinder oil is used for ?
•2-stroke engine
15
110. What is the importance of the control box of a differential gear system in a steering gear system?.
•it conpares the bridge signal to the actual rudder angle through the follow up gear
16
158. Labyrinth seals used to reduce leakage around a turbine shaft are constructed of
•machined packing strips or fins
17
175. Main component of the engine to regulate speed is the ?
•governor
18
123. Distortion of the spray pattern of a nozzle or injector maybe indicated by alan ?
•cooling water temperature rise
19
104. The capacity of a rotary pump, when operated at a constant speed, will decrease with an increase in the pump?
•rotor clearances
20
134. One of the routine tasks onboard maintenance for Gas Turbine is mainly of daily visual checks of the running engine. What are you going to execute after a fix number of operating hours to remove any salt deposits on the compressor?
•Internal water wash
21
186. The capacity of a rotary pump, delivering a constant viscosity fluid, will decrease when the discharge pressure is increased, due to ?
•increased slippage
22
153. Which of the following determines the measured gap between the face of the burner atomizer tip nut and the dfifuser plate ?
•Distance piece
23
101. Air leaking into a flash type distilling plant could occur through
•gasketed joints, valve stem, and gage glass packing
24
200. Irregular feeding or surging of the feedwater supply to a low pressure distilling plant may be attributed to
•A dirty strainer in the saltwater feed pump suction line
25
119. The average pressure exerted on a piston during each power stroke is termed
•mean effective pressure
26
132. Integral water jacket liners use O-rings near the bottom of the liner. These O-rings serve to ?
•prevent the escape of lubricating oil from the crankcase
27
131. Inspection of a low pressure gear pump for cavitation will usually be indicated by a wear pattern ?
•along the inlet side of the housing
28
170. Which of the following is the result of excessively high fuel oil temperature ?
•Fouling of the heaters
29
182. If a reciprocating air compressor has a knock occurring in frequency with its operating RPM, the cause is probably
•misalignment or worn main bearings
30
107. Which combination of the main shaft segments listed below, that are located furthest from the main engine are connected by the inboard stern tube shaft coupling?
•Line shaft and stern tube shaft
31
139. Increasing the speed of a centrifugal pump will result in an increase in the pump capacity. Another means of increasing the total head pressure of a centrifugal pump is to increase the ?
•diameter of the impeller
32
121. The working principle of an engine is the conversion of ?
•heat into mechanical energy,
33
105. Fluctuations in the pressure and temperature of the steam supplied to the first-effect of a low pressure submerged tube distilling plant will cause
•pressure and temperature fluctuations in the entire unit
34
142. How does a quick closing valve operate?
•the valve bridge is collapse remotely allowing the valve to close
35
172. In the boilerás combustion control system, when the demand for steam is increased
•air supply increases before fuel supply increases
36
140. Which of the following component is the primary shaft emerging out of the engine?lt directly receives the rotational motion from the crankshaft and rotates at the maximum velocity in high speed engines.
•thrust shaft
37
161. What is the reason why fuel is heated before atomizing is to ?
•decrease its viscosity
38
130. How do you control freshwater heating temperature in the evaporator side of a Fresh Water Generator?
•Regulate outlet valve
39
193. Why diesel engine lubricating oil need more purification compare with the lubricating oil in a gas turbine?
•gas turbine lubricant does not come into contact with the combustion process
40
196. Part of centrifugal disc purifier use to hold discs in place and directs the flow of dirty liquid to the bottom then to the discs as the oil flows upward is called
•distributor
41
173. The purpose of the diffuser in a boiler burner assembly is to
•allow some mixing of fuel and air
42
144. How is viscosity of fuel in the atomizer can be reduced ?
•increasing the fuel oil heater steam supply
43
191. What is the most important rule for the safe operation of a boiler?
•Maintain the proper water level at all times
44
199. If you were operating a centrifugal water service pump with worn wearing rings, the
•pump would develop insufficient flow
45
162. Which of the listed conditions is responsible for causing the gland leak off steam from a propulsion turbine to pass through the gland exhaust condenser?
•The use of a gland exhauster fan
46
145. In an engine operation what is the effect called that describes the unstable operation of the governor that will not maintain a steady state condition ?
•Hunting
47
198. Which of the following terms is used to identify the pressure of the liquid ?
•Suction head
48
151. What is the possible cause of fuel oil accumulation in boiler casing is ?
•dripping atomizers
49
181. In a main propulsion turbine installation, the condensate pump initially discharges to the
•air ejector condenser
50
183. The range of values around a set point of a measured variable where "no action"occurs in an automatic flow controller is called:
•Deadband
51
113. Which of the following cases listed below should soot blowing be applied to avoid soot fires ?
•Prior to an increase in power
52
136. What is the cause of excessively low air pressure occurring in the intercooler of a reciprocating air compressor?
•leaky discharge valves on the LP cylinder
53
133. What part of the boiler provides water circulation to the waterwall tubes?
•Downcomers
54
195. Why is it necessary to transfer fuel oil to the settling tanks ?
•allow the sediments and water to settle
55
150. What type of pump is used in the steering gear of modern ship?
•Vane
56
190. Main engine lube oil sump tank is located ?
•at the bottom of the engine
57
117. The dehydrator of a refrigeration system is located ?
•before expansion valve
58
143. If the boiler fires are extinguished by water contamination in the fuel oil, you should FIRST?
•secure the burner valves
59
155. Why is thin tipping design procedure is used in modern reaction turbines ?.
•reduce tip leakage
60
102. A salinity indicating system functions on the basic principle of measuring the
•electrical conductivity of water
61
179. Boiler safety valves are set not to go above maximum operating pressure of higher than ?.
•0.1
62
174. What is the purpose of the dehydrator in refrigeration?
•Remove refrigerant moisture
63
165. The function of seal cages, or lantern rings installed in the centrifugal pump stuffing boxes, is to
•distribute the sealing liquid within the stuffing box
64
126. Which of the following would result if the temperature of the fuel to the burners is too low?
•The boiler will produce heavy black smoke
65
115. If the flow of water from the centrifugal pump is allowed to be stopped by closing the discharge valve while the pump continues to run for an extended period, which of the following will occur?
•liquid in the pump will overheat
66
146. The possible cause why lube oil pumps fail to build up discharge pressure could be that the ?
•suction valve is closed
67
188. Which of the following statement is correct when a piston is said to be at top dead center?
•nearest to the cylinder head
68
176. Movement of the pump control rack in a fuel injection system having individual plunger-type pumps
•changes the length of the pump stroke
69
135. What causes carbon deposits in the fuel heater?
•high fuel temperature,
70
154. Most of the fuel injection pumps will then closed after injection because they are fitted with a ?
•spring loaded discharge check valve
71
169. How will you know the firing rate of boiler using steam atomization indicated?
•By the fuel oil pressure
72
124. What precaution should be observed to prevent damage of the service pump when warming up the fuel system to the boiler is to ?
•close the recirculating valve when atomizing temperature is reached
73
180. Why should hydraulic cranes be properly warmed-up before they are used?
•Hydraulic fluid must be at the proper viscosity
74
111. Which of the following component is the primary shaft emerging out of the engine. It directly receives the rotational motion from the crankshaft and rotates at the maximum velocity in high-speed engines.
• Thrust shaft
75
103. To keep the movement of the rudder closely in step with the steering wheel, which of the devices listed, when used on an electro-hydraulic steering gear?
• The follow-up gear.
76
127. Prior to starting, the purpose of turning over a main propulsion diesel engine with the cylinder test cocks open, is to ?
•remove condensation and other liquids from the cylinders
77
168. How is constant steam pressure maintained?
•By controlling the amount of heat supplied to the boiler
78
171. Which equipment must be tested NOT more than 12 hours prior to getting underway from a port when the voyage is to be of 48 hours or greater duration?
•Steering gear
79
148. How many fuel oil heaters are required for main engine operation ?
•at least two heaters of approximately equal size are to be installed
80
167. The bore of a diesel engine describes the ?
•AA diameter of the cylinder
81
185. If you hear a crackling sound coming from a salt water centrifugal pump casing, the most probable cause of the noise would be ?
•excessive suction lift
82
147. Which of the following statement is correct relative to distillation plant operation?
•Distillation is the process of boiling seawater to produce vapor which is condensed into fresh Water
83
184. Passages are drilled at the diesel engine crankshaft in order to provide lubricating oil in the ?.
•piston rod bearings
84
120. Strainer is commonly used in hydraulic system in order to ?
•prevent solid particles from entering the pump.
85
178. One of the routine tasks onboard maintenance for Gas Turbine is mainly of daily visual checks of the running engine. What are you going to execute after a fix number of operating hours to remove any salt deposits on the compressor?
•Internal water wash
86
116. What is the characteristic of a one ton air conditioning system?
•Its cooling power equals melting 907 kg.(2000 lbs) of ice per day.
87
157. If turbine rotor shafts extend through the casing, what external source of sealing steam is used in conjunction with labrynith packing ?.
•seal the casing during periods of low casing pressure
88
The firing rate of boiler using steam atomization is indicated by the ?
•fuel oil supply pressure
89
164. A squeaking sound occurring from within an operating reciprocating air compressor is an indication of ?
•tight compressor bearings
90
177. Most fuel injection nozzles are opened by ?
•fuel oil pressure
91
128. If the fixed orifice in the evaporator steam supply line were to be removed, the steam pressure reducing valve located upstream would
•be unable to maintain steam flow unless the proper range spring were to be installed
92
159. Visual inspection of a fuel injector valve, removed during overhaul, shows heat discoloration of the lower end of the valve. This is an indication of
•valve leakage
93
129. What action would you take to perform the most important rule for the safe operation of a boiler?
•Maintain the proper water level at all times
94
166. An oil mist detector is used to detect an oil mist formation in the diesel engine crankcase. Which of the following causes oil mist formation ?
•overheating of Oil
95
160. An internally mixed steam atomizer requires which of the following compared to a return flow oil burner system?
•Less excess air
96
187. The measure of the amount of salt present in water is called ?
•Salinity Specific Gravity.
97
192. When turbine rotor shafts extend through the casing, an external source of sealing steam is used in conjunction with labyrinth packing to.
•seal the casing during periods of low casing pressure
98
114. What is the use of a steam control valves installed in the auxiliary exhaust line?
•Control steam admission and maintain the proper steam spray pattern in the DC heater
99
122. The function of a centrifugal pump double volute casing is to ?
•reduce radial thrust on the impeller
100
109. Movement of the pump control rack in a fuel injection system having individual plunger-type pumps ?
•changes the length of the pump stroke