Question 451Motor Plants - Assistant Engineer

70% to pass

The thrust bearing shown in the illustration has over eight years of ahead running time. Measurements show "i1" is 4 mm and "i2" is 1 mm. Which of the following conditions is indicated and what steps should be taken, if any? Illustration MO-0121

Diagram for USCG Motor Plants Assistant: The thrust bearing shown in the illustration has over eight years of ahead...

ANo appreciable wear has occurred, and the proper maintenance procedures should continue to be followed.

BA wear rate of 1.6 mm per year occurred. Although not excessive, this condition may require more frequent monitoring.

CThe stops in which the thrust bearing block rides are worn, and it is necessary to return these to their original specifications.

DA wear rate of 1.6 mm per year is excessive and requires immediate assistance from the manufacturer’s field support.

AI Explanation

The correct answer is A) No appreciable wear has occurred, and the proper maintenance procedures should continue to be followed. The reasoning is that the measured "i1" of 4 mm and "i2" of 1 mm indicate the thrust bearing has only 3 mm of wear over the 8 years of operation, which is a very low wear rate. This suggests the thrust bearing is still within its normal operating parameters and does not require any special attention beyond the proper maintenance procedures. The other options are incorrect because they indicate excessive wear or issues that are not supported by the provided information.

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