Predictive & Preventive Maintenance Flashcards
7 cards from real MMC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Predictive & Preventive Maintenance flashcards as text
Which parameter measured during laser shaft alignment indicates angular misalignment?
Answer: Difference in slope between driver and driven shaft centerlines
Angular misalignment is indicated by a difference in the slope (angle) of the two shaft centerlines, measured as a gap difference across the coupling face.
In predictive maintenance, 'severity criteria' for vibration measurements are used to:
Answer: Determine safe operating limits and trigger maintenance actions at defined thresholds
Severity criteria (such as ISO 10816 levels) establish alert and danger thresholds so maintenance actions are triggered at the right time based on measured vibration levels.
When balancing a rotating component, 'residual unbalance' refers to:
Answer: The unbalance remaining after a balancing correction has been applied
Residual unbalance is the amount of unbalance that persists in the rotor after the balancing process is complete, which should meet the tolerance for the machine's speed and mass.
A plant switches from time-based bearing replacement to vibration-based on-condition replacement. The most significant expected benefit is:
Answer: Extension of bearing service life and reduction of unnecessary replacements
On-condition replacement allows bearings to run until degradation is detected, avoiding premature replacement of serviceable bearings while still preventing run-to-failure.
Infrared thermography on a refractory-lined furnace wall identifies a cold spot. This most likely indicates:
Answer: Refractory degradation or loss causing increased heat loss through the shell
A cold spot on the outer shell typically indicates that the refractory lining has thinned or deteriorated, allowing more heat to escape and raising shell temperature (or revealing a gap).
Which of the following best describes a 'living PM program'?
Answer: A program continuously updated based on actual failure data, equipment history, and reliability metrics
A living PM program is regularly reviewed and revised using real equipment failure data and performance metrics to ensure tasks remain relevant and effective.
What does the 'age exploration' phase in RCM involve?
Answer: Collecting failure age data to establish whether a failure has an identifiable age-related pattern
Age exploration collects and analyzes failure age data to determine whether equipment exhibits an increasing failure probability with age, justifying time-based tasks.