The lubrication system of an engine provides a supply of lubricating oil to the various moving parts...
an engine. Its main function is to enable the formation of a film of oil between the moving parts, which
reduces friction and wear. The lubricating oil is also used as a cleaner and in some engines as a coolant. The
usual method of bearing lubrication is by forced feed system, which supplies oil to all bearings, so that a
film of oil is maintained on the journal and bearing surfaces.
(The following 2 questions are based on the passage above.)
参考解析:
1. The forced feed system is put into use in order to _____.
A. supply oil to all parts of the engine
B. lubricate the bearing and the piston
C. maintain a film of oil on the journal and bearing surfaces
D. maintain a film of oil on the piston surfaces only
2. What is the function of lubricating oil?
A. Formation of a film of oil between the moving parts, which reduces friction and wear.
B. Used as a cleaner.
C. As a coolant in engines.
D. All of the above.
Fresh water is used for the cooling of the cylinder jackets and covers of the main engine, whereas the
various cooling liquids which circulate the engine are themselves cooled by sea water, such as, sea water is
used for the cooling of the oil in the lubricating oil cooler as well as the fresh water. In an emergency
situation, for example in the event of damage to a fresh water cooler or generator, the sea water pumps can
be used to supply sea water to the fresh water cooling system, merely by removing the blind-flanges.
(The following questions are based on the passage above. )
3. In which situation we should use sea water system instead of fresh water system?
A. When sea water pumps are damaged.
B. When sea water cooler is damaged.
C. When fresh water pumps are damaged.
D. The blind-flanges are broken.
4. The word “merely” in this paragraph could best be replaced by_____.
A. only
B. necessary
C. but
D. if