Question 419General Subjects - 1st Asst/Chief

The correct answer is B) Degradation of a ball or a roller bearing. High amplitude/displacement readings at a very high frequency at one measuring point indicate the presence of a defective bearing. As bearings degrade, they can produce high-frequency vibrations due to the rolling motion of the ball or roller elements over damaged raceways or surface irregularities. This is a characteristic signature of bearing degradation that can be detected through vibration analysis. The other options are incorrect because looseness (A) would typically produce lower-frequency vibrations, misalignment (C) would produce vibrations at the rotational frequency and its harmonics, and imbalance (D) would produce vibrations at the rotational frequency.