ITMC Preventive Maintenance & Troubleshooting 3 — Questions and Answers
Question 1: A technician is using the 'run-to-failure' maintenance strategy for a component. This approach is MOST appropriate when:
- The component is critical to production and expensive to replace
- The component is non-critical and its failure has no safety or production impact (Correct answer)
- The component has a predictable wear-out failure mode
- Replacement parts have a long lead time
Correct answer: The component is non-critical and its failure has no safety or production impact
Run-to-failure is cost-effective only for non-critical components whose failure causes no safety hazard or significant production loss.
Question 2: Which type of coupling is MOST forgiving of angular misalignment between two shafts?
- Rigid flange coupling
- Jaw (spider) coupling
- Gear coupling (Correct answer)
- Sleeve coupling
Correct answer: Gear coupling
Gear couplings can accommodate both angular and parallel misalignment through the meshing of crowned gear teeth, making them highly flexible.
Question 3: A plant uses oil analysis as a predictive maintenance tool. An increase in ferrous metal particle count in a gearbox sample indicates:
- Normal additive depletion
- Abnormal wear of steel gear components (Correct answer)
- Water contamination in the oil
- Oxidation of the lubricant
Correct answer: Abnormal wear of steel gear components
Elevated ferrous particle counts in oil analysis indicate that steel or iron components inside the gearbox are experiencing abnormal wear.
Question 4: During a PM task, a technician notices a gearbox is operating significantly hotter than its normal temperature baseline. What is the MOST logical first step?
- Immediately shut down the equipment
- Check the lubricant level and condition (Correct answer)
- Replace the gearbox bearings
- Increase the cooling fan speed
Correct answer: Check the lubricant level and condition
Low lubricant level or degraded oil is the most common cause of elevated gearbox temperature and should be verified before taking more invasive action.
Question 5: What is the PRIMARY purpose of a CMMS (Computerized Maintenance Management System) in a PM program?
- To automate equipment repairs without technician involvement
- To schedule, track, and document maintenance activities and asset history (Correct answer)
- To replace manual lubrication routes with automated systems
- To monitor real-time equipment vibration data
Correct answer: To schedule, track, and document maintenance activities and asset history
A CMMS centralizes the scheduling, tracking, and documentation of maintenance work orders and equipment history to optimize PM programs.
Question 6: A technician measures the current draw of a three-phase motor and finds one phase is drawing significantly more current than the other two. The MOST likely cause is:
- Motor is operating at full load
- An open or high-resistance phase in the supply circuit (Correct answer)
- The motor needs lubrication
- Ambient temperature is too high
Correct answer: An open or high-resistance phase in the supply circuit
An open or high-resistance connection on one phase forces the other phases to carry more current to compensate, causing current imbalance.
Question 7: In the context of PM scheduling, what does the term 'condition-based maintenance' (CBM) mean?
- Maintenance performed on a fixed calendar interval
- Maintenance triggered by actual equipment condition data (Correct answer)
- Maintenance performed only after equipment failure
- Maintenance based on manufacturer recommendations only
Correct answer: Maintenance triggered by actual equipment condition data
Condition-based maintenance uses real-time or periodic equipment condition data (vibration, temperature, oil analysis) to trigger maintenance only when needed.
ITMC Preventive Maintenance & Troubleshooting 3
A technician is using the 'run-to-failure' maintenance strategy for a component.
This approach is MOST appropriate when: