問題一覧
1
The ability of lubricating oil to resist viscosity changes during temperature changes is indicated by the________
viscosity index number
2
If the capacity of a centrifugal pump decreases gradually over a long period of time, you should replace the _____ .
wear rings
3
When securing a distillate pump on a low pressure fresh water evaporator, which of the listed steps should be carried out first?
Trip the threeway solenoid dump valve
4
A hydraulic system gear pump being fed from a reservoir frequently indicates signs of excessive pitting after two months of service. Which of the following would most likely contribute to this condition?
A vacuum condition has developed in the reservoir
5
The minimum delivery pressure required for diesel engine fuel oil injection depends primarily on the ___________.
firing pressure in the engine
6
Fuel oil penetration into the cylinder of a diesel engine is ___________.
reduced by finer atomization
7
Which of the following precautions should be observed concerning the introduction of a fire resistant fluid into a hydraulic system?
Deterioration of paints, seals, metals, and electrical insulation may occur.
8
A good quality oil used in main propulsion engine lubrication systems should be _____________.
resistant to permanent emulsification
9
Fuel supplied by each unit injector on a two stroke cycle single acting diesel engine is directed into each cylinder at a very high pressure through the ___________.
spray tip of the injector
10
Very small irregularities on the seat and disk of a globe valve may be manually repaired with the valve in place by the process known as _____________.
lapping in
11
When assembling a run of liquid service piping, which of the following factors should be considered? I. How the type of fittings used will affect the flow II. What type of gasket material should be used III. What radius should be used for each bend in the
A. I, II & III
12
The injection pressure of a hydraulic fuel injection nozzle can be increased by _______.
increasing compression on the pressure spring
13
Zinc anodes are installed in a marine raw‐water cooling system to _____________.
control electrolysis
14
To correctly identifies the position of the journal when the shaft is ______.
just beginning to rotate
15
A hydraulic system gear pump being fed from a reservoir frequently indicates signs of excessive pitting after two months of service. Which of the following would most likely contribute to this condition?
A vacuum condition has developed in the reservoir
16
The minimum delivery pressure required for diesel engine fuel oil injection depends primarily on the ___________
firing pressure in the engine
17
Fuel oil penetration into the cylinder of a diesel engine is ___________.
reduced by finer atomization
18
Which of the following precautions should be observed concerning the introduction of a fire resistant fluid into a hydraulic system?
Deterioration of paints, seals, metals, and electrical insulation may occur.
19
A good quality oil used in main propulsion engine lubrication systems should be _____________.
resistant to permanent emulsification
20
Fuel supplied by each unit injector on a two‐stroke cycle single acting diesel engine is directed into each cylinder at a very high pressure through the ___________.
spray tip of the injector
21
Very small irregularities on the seat and disk of a globe valve may be manually repaired with the valve in place by the process known as _____________.
lapping in
22
The injection pressure of a hydraulic fuel injection nozzle can be increased by _______.
increasing compression on the pressure spring
23
Zinc anodes are installed in a marine raw‐water cooling system to _____________.
control electrolysis
24
Main propulsion engine lube oil sumps should be constructed _________.
with a sloped bottom
25
The amount of fuel injected into a diesel engine cylinder by a unit injector, is controlled by ___________.
a metering helix inside the pump
26
Gate valves should not be used for throttling as __________.
wire drawing of the disc will result
27
f the chemical analysis of a lube oil sample taken from the main propulsion machinery indicates an increased neutralization number the _______.
acidity has increased
28
Assuming oil and water flow rates remain the same, what would be the effect of scale formation occurring on the inside of the cooling water tubes of a lube oil heat exchanger?
water temperature outlet temperature will decrease and the lube oil temperature will increase
29
The combustible element in fuel that could cause major air pollution is _______.
sulphur
30
The viscosity of fuel oil is indicated by its____________.
internal friction
31
The final heating of the feedwater in a flash type distilling plant is carried out by______.
low pressure steam admitted to the feedwater heater
32
Which of the listed conditions can lead to cavitation in a centrifugal pump?
Vapor pockets formed in the suction flow stream
33
If you attempt to tighten a leaking hydraulic fitting with pressure on the system, you will _____.
find that the pressure will prevent the components from being tightened
34
To correctly identifies the position of the journal when the shaft is ______.
just beginning to rotate
35
Tube scaling in heat exchangers causes the heat transfer rate to decrease because the _____.
thermal conductivity of the scale is very low
36
While the oilywater- seperator is operating in the processing mode, if a low vacuum, what is the probable cause?
The coalescer beads are severely fouled
37
The harmful effect of sulfur present in the boiler fuel oil is that it ___________.
forms corrosive acids when mixed with water
38
What do next after adding grease to a ball bearing with a hand held grease gun?
Run the machine with the bearing housing drain plug open for a short while
39
What happen when you heat the oil?
It makes the oil less viscous
40
What instrument or process determines the BTU value of boiler fuel oil?
Calorimeter
41
Greases are generally produced by ____.
saponifying a metal base, to which oil is then added and mixed under controlled temperature
42
If one of the bilge system manifold valves does not properly seat, the__________.
bilge system will lose vacuum and prevents the other bilges from being pumped out
43
When securing a centrifugal type distillate pump, which of the listed steps should be carried out first?
Trip the three way dump valve
44
Which of the following statements represents the proper relative direction of flow through a globe valve?
Direction of flow should be from below the seat
45
In a two stage flash evaporator, heated feedwater is vaporized in the_________.
first and second stage flash chambers
46
In a centrifugal pumps operating with a high suction lift, foot valves are primarily designed to______. .
enable the pump and its suction line to remain primed prior to starting the pump
47
Which of the following centrifugal pump components converts the liquid velocity to pressure?
Volute
48
An oil fog lubrication system is recommended for______.
high speed continuous operation of roller bearings
49
The first step when beginning to set the slide valves on a duplex reciprocating pump is to _____
center the steam piston in the cylinders
50
If you are operating a centrifugal water service pump with worn wear rings, the____
pump discharge capacity is reduced