Pumproom
Generator room
A space adjacent to a cargo tank
A space two meters from a cargo valve
第1题：
A person may operate an air compressor in which of the following areas on board a tank barge ________．
A.Pumproom
B.Generator room
C.A space adjacent to a cargo tank
D.A space two meters from a cargo valve
第2题：
Protects against suction valve float
Provides a positive pressure on the air inlet valves
Prevents lubricating oil contamination of the compressed air supply
Protects against the damaging effects of airborne solid particles
第3题：
第二组
Under normal operation, some lubrication oil mist may be discharged from the air compressor to the air start system. This oil may be from excess compressor cylinder lubrication, from faulty oil scraper rings, or may even be suspended oil vapor contaminating the engine room atmosphere and drawn in at the compressor suction. Oil discharge is kept to a minimum by draining the after cooler, air receiver and starting system. If small quantities of lubrication oil do get passed into the starting air system, they will deposit as thin moist film over internal pipe surfaces but are not readily combustible. If a cylinder non-return valve leak while the engine is in operation, some hot gas, possibly with unburned fuel and cylinder lubrication oil, may be blown through the valve to the adjacent air manifold. With further heating from the leaky valve, this, together with the already deposited oil film, will carbonize and form. incandescent carbon. If starting air is applied to the system while still hot, the high pressure air coming into contact with the burning carbon may cause an explosion. Such an explosion will cause a flame to pass back through the air start pipe system, evaporating the deposited oil film and igniting it in the presence of air. Very high velocities and shockwaves are generated which may rupture pipes and fittings.
Alternatively, if excessive oil has entered the air start system, a mixture of air and oil droplets may be discharged through the open cylinder non-return valve during starting. This spray may ignite due to high temperatures in the cylinder, causing a flame through the still open valve to the air manifold.
To prevent an explosion, air start valves must be correctly maintained and lubricated to ensure correct timing and free movement with positive closing. Oil in the system must be kept to a minimum, pipe lines must be drained and cleaned internally when necessary and oil discharge from air compressors must be kept to a minimum by good maintenance.
The passage is mainly about
A.crankcase explosion
B.scavenge box fire
C.starting air pipe
D.the danger of explosion in the starting air system
第4题：
starting air pressure too high
correct timing of starting air valves
three of the six starting valves stuck
the turning gear disengaged
第5题：
increase compressor discharge pressure on demand
increase compressor operating speed as necessary
allow the motor to turn the compressor opposed only by friction
reduce the compressor frictional load when starting
第6题：
All VHF marine band radios operate in the simplex mode，which means that______．
A.only one person may talk at a time
B.only two persons may talk at the same time
C.the radio only transmits
D.the radio only receives
第7题：
charge air receiver
scavenging air belt
turbine
air cooler
第8题：
Sludge may form in the crankcase of an air conditioning compressor as a result of ______.
A.bubbling refrigerant
B.overheating and oxidation
C.lowered operating temperatures
D.reducing the cloud or floc point
第9题：
bubbling refrigerant
overheating and oxidation
lowered operating temperatures
reducing the cloud or flash point
第10题：
which may confirm that the person knows no details about the question
lack of which may confirm that the person knows details about the question
which may help prove that the suspect hasn’t committed a crime
lack of which may mean that the suspect hasn’t committed a crime