問題一覧
1
What is the main function of a valve in a piping system?
To regulate flow
2
What is the function of a non-return valve in a piping system?
To prevent backflow
3
Which type of pump is commonly used for transferring fuel oil in a ship's piping system?
Gear pump
4
Which type of valve is commonly used for isolating a portion of the piping system?
Gate valve
5
Which type of pump is commonly used for transferring seawater in a ship's piping system?
Centrifugal pump
6
Which of the following is NOT a typical maintenance requirement for a pump operating within its nominal performance range?
Motor rewinding
7
What is the typical suction lift limit for a standard pump operating within its nominal performance range?
10-20 feet
8
What is the recommended maximum flow rate for a pump with a 2-inch discharge line?
150 gallon per minute
9
What is the maximum head pressure that can be generated by a pump with a 50-horsepower motor?
250 psi
10
What is the typical efficiency rating for a centrifugal pump operating within its nominal performance range?
70-80%
11
What is the primary purpose of a ballast pump on a ship?
To adjust the ship's stability
12
What is the purpose of a ballast tank air pipe?
To provide ventilation to the ballast tank
13
Which type of ballast pump operates by using air pressure to expel water?
Diaphragm pump
14
Which of the following is a common cause of ballast pump cavitation?
Low suction lift
15
What is the minimum recommended flow rate for a ballast pump?
200 m3/hour
16
When emptying a ballast tank, how should you adjust the pump speed?
Decrease the speed as the tank empties
17
What should you do if there is a leak in the ballast system?
Stop operation and repair the leak immediately
18
When filling a ballast tank, how should you adjust the pump speed?
Increase the speed as the tank fills
19
What should you do if the ballast pump is not supplying sufficient flow or pressure?
All of the above
20
What should you do if you suspect a problem with the ballast pump motor?
Monitor the situation and report to the captain
21
What is the first step in troubleshooting a pump?
Check the power source
22
What is the primary function of a check valve?
To prevent backflow
23
How can you prevent valve leakage?
Check the valve packing
24
How can you diagnose a leaking fitting?
Use a pressure gauge
25
How can you troubleshoot a stuck valve?
AllI of the above
26
What is the main cause of cavitation in pumps?
Inadequate NPSH (Net Positive Suction Head)
27
Which of the following is a common cause of pump overheating?
Low flow rate
28
How can you check for air or gas entrainment in a pump system?
Observe fluid flow characteristics
29
What can cause a sudden loss of pump pressure?
Air leakage in the suction line
30
What is a common cause of pump suction line blockage?
All of the above
31
What is the main purpose of an air compressor on a ship?
To provide compressed air for pneumatic tools and equipment
32
What type of compressor is commonly used on ships?
Reciprocating compressor
33
What is the working principle of a reciprocating air compressor?
Air is compressed by a reciprocating piston
34
How are lubricants distributed in a reciprocating air compressor system?
Through a self-contained oil pump
35
What are the potential hazards associated with working with air compressors?
Risk of injury from flying debris or bursts of compressed air
36
What is the first step in starting up an air compressor?
Turn on the power supply
37
How long should you allow an air compressor to run without load before starting to use it?
15-20 minutes
38
How often should you check the oil level in an air compressor system?
Every day
39
What is the purpose of a pressure gauge in an air compressor system?
To measure the pressure of the compressed air
40
What should you do if you notice an abnormal noise coming from an air compressor during operation?
Shut down the compressor and investigate the source of the noise
41
What is the recommended oil type for a rotary screw compressor?
Synthetic oil
42
How often should the compressor oil be changed?
Every 500 hours of operation
43
What is the most common cause of air compressor overheating?
All of the above
44
What is a potential sign of a leak in an air compressor system?
Decreased air pressure in the system
45
What is the recommended maximum level of moisture in compressed air?
2%
46
What should you do if the compressor pump continuously runs without stopping?
Replace the check valve
47
Why does the compressor produce humid air?
Dirty air filter
48
Why does the compressor overheat?
Dirty cooling system
49
What could be the cause if the compressor is producing an unusual noise?
Worn out piston rings
50
What should you do if the compressor keeps cycling on and off rapidly?
Check the pressure switch