Preventive & Predictive Maintenance Flashcards

Laser shaft alignment of a motor and pump coupling primarily helps prevent which problem?

Answer: Premature bearing and seal failure from misalignment forces

Misalignment loads bearings and seals, and precision alignment reduces vibration and extends their life.

Vibration analysis showing high axial vibration at 1x and 2x running speed most often indicates what condition?

Answer: Shaft misalignment

Misalignment, especially angular, commonly produces strong axial readings at 1x and 2x speed.

Monitoring differential pressure across an air handler filter bank is an example of which maintenance strategy?

Answer: Condition-based maintenance

Replacing filters when pressure drop reaches a set point bases the action on actual condition.

For which type of asset is a run-to-failure strategy most appropriate?

Answer: Low-cost, non-critical items where failure has minimal consequences

Run-to-failure is acceptable when failure is cheap, safe, and easily corrected, such as a single light bulb in a storage room.

What does the term 'PM optimization' typically involve?

Answer: Reviewing PM tasks to remove non-value tasks, adjust frequencies, and add condition-based tasks

PM optimization refines the existing program so each task addresses a real failure mode at the right interval.

Which piece of information is most important to include on a well-written PM work order task list?

Answer: Specific measurable steps and acceptable limits, such as torque values or temperature ranges

Clear, measurable criteria ensure consistent execution and let technicians recognize out-of-tolerance conditions.

Motor current signature analysis (MCSA) is particularly useful for detecting which fault?

Answer: Broken rotor bars in induction motors

MCSA identifies sideband frequencies in the current spectrum that indicate broken or cracked rotor bars.