CPM Maintenance and Reliability 2 — Questions and Answers
Question 1: Which metric represents the average time between consecutive failures of a repairable system?
- Mean Time To Repair (MTTR)
- Mean Time Between Failures (MTBF) (Correct answer)
- Overall Equipment Effectiveness (OEE)
- Failure Mode and Effects Analysis (FMEA)
Correct answer: Mean Time Between Failures (MTBF)
MTBF measures the average elapsed time between failures of a repairable system, serving as a key reliability indicator.
Question 2: A plant implements a maintenance strategy where assets are replaced or serviced at fixed time intervals regardless of condition. This is called:
- Predictive maintenance
- Corrective maintenance
- Preventive maintenance (Correct answer)
- Reliability-centered maintenance
Correct answer: Preventive maintenance
Preventive (or time-based) maintenance schedules service at fixed intervals to reduce the likelihood of failure, independent of equipment condition.
Question 3: In Reliability-Centered Maintenance (RCM), the primary objective is to:
- Minimize total maintenance labor hours
- Preserve system function at the lowest cost (Correct answer)
- Replace all components on a fixed schedule
- Maximize spare parts inventory
Correct answer: Preserve system function at the lowest cost
RCM focuses on preserving system functions safely and cost-effectively by selecting the most appropriate maintenance strategy for each failure mode.
Question 4: A root cause analysis (RCA) of a recurring pump failure reveals that inadequate lubrication is the root cause. What type of root cause is this?
- Physical root cause (Correct answer)
- Human root cause
- Latent root cause
- Systemic root cause
Correct answer: Physical root cause
A physical root cause is the actual material condition (such as lack of lubrication) that directly caused the failure.
Question 5: Which of the following is NOT a component of Overall Equipment Effectiveness (OEE)?
- Availability
- Performance
- Quality
- Maintainability (Correct answer)
Correct answer: Maintainability
OEE is calculated from Availability, Performance, and Quality; maintainability is a reliability concept but not an OEE component.
Question 6: Vibration analysis is most commonly used to detect which type of equipment fault?
- Corrosion under insulation
- Bearing wear and imbalance (Correct answer)
- Electrical insulation breakdown
- Fatigue cracks in pressure vessels
Correct answer: Bearing wear and imbalance
Vibration analysis is the primary predictive maintenance technique for detecting bearing defects, imbalance, misalignment, and looseness in rotating equipment.
Question 7: A maintenance planner uses a Bill of Materials (BOM) to:
- Schedule technician work shifts
- Identify all parts needed for a maintenance task (Correct answer)
- Prioritize work orders by criticality
- Calculate equipment downtime costs
Correct answer: Identify all parts needed for a maintenance task
A BOM lists all components, sub-assemblies, and materials required to complete a maintenance task or repair.
Which metric represents the average time between consecutive failures of a repairable system?