6-53.
The following statements concern the main
propulsion thrust bearing and a main
propeller spring bearing.
Which
statement is correct?
1.
Both bearings are lubricated by the
main lubricating oil system
2.
The former is lubricated by the
auxiliary machinery lubricating oil
system and the latter by an
independent oil system
3.
Both bearings are lubricated by the
same independent oil system
4.
The former may be lubricated by the
reduction gear oil system and the
latter by an independent oil system
6-54.
How often should personnel of a ship in
an operating status check the main
propulsion shaft bearing lube oil supply
levels and temperatures?
6-55.
1.
Daily
2.
Twice a day
3.
Once during a watch
4.
Hourly
How often should main shaft spring
bearing clearance readings be taken?
1.
Monthly
2.
Quarterly
3.
Semi-annually
4.
Yearly
6-56.
The area between the rotating propeller
shaft and the stern tube is sealed by
which of the following devices?
1.
Fairwater sleeve
2.
Stern-tube gland
3.
Bearing bushing
4.
Bulkhead gland
Question 6-57 is to be judged True or
False.
6-57.
A firemain connection is fitted to the
forward space of the stuffing box for the
purpose of maintaining a positive flow of
water through the stern tube.
6-58.
Which of the following materials is used
to prevent excessive leakage of seawater
into the ship through the stern tube?
1.
Carbon
2.
Rubber
3.
Babbitt
4.
Flax
6-59.
Which of the following types of bushings
are usually found on strut bearings?
1.
Lignum vitae
2.
Laminated resin-bonded
3.
Rubber
4.
All of the above
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