CRE Equipment and Tools Knowledge 4

Question 1

A CMMS (Computerized Maintenance Management System) work order history is being used for reliability analysis. Which metric is DIRECTLY calculated from work order timestamps?

Accepted Answer

Mean Time To Repair (MTTR)

Answer

Weibull shape parameter

Answer

Failure Mode and Effects criticality

Answer

Fault Tree probability

Question 2

In a vibration velocity spectrum, a peak at 2× gear mesh frequency with sidebands spaced at shaft speed is MOST likely caused by:

Accepted Answer

Gear tooth wear or load distribution problem

Answer

Bearing inner race defect

Answer

Resonance

Answer

Imbalance

Question 3

Which insulation resistance test parameter best indicates the rate of moisture or contamination build-up on motor windings over time?

Accepted Answer

Insulation resistance trend over multiple test dates

Answer

Dielectric absorption ratio (DAR)

Answer

Polarization index (PI)

Answer

Winding resistance balance

Question 4

When using a dial indicator to measure shaft runout, a total indicator reading (TIR) of 0.006 inches is recorded. The actual eccentricity of the shaft is:

Accepted Answer

0.003 inches

Answer

0.006 inches

Answer

0.012 inches

Answer

0.001 inches

Question 5

A reliability engineer uses a proof test to validate the safety function of a pressure relief valve. The primary purpose of proof testing in this context is to:

Accepted Answer

Reveal dangerous undetected failures that accumulate between tests

Answer

Measure the valve's flow coefficient

Answer

Determine the valve's set pressure accuracy

Answer

Calibrate the pressure instrumentation

Question 6

In route-based vibration monitoring, the purpose of using a consistent measurement location marked with a hard-mount stud versus a hand-held probe is to:

Accepted Answer

Eliminate variability from probe placement and improve trend repeatability

Answer

Reduce the time per measurement point

Answer

Increase the frequency range captured

Answer

Allow wireless data transmission

Question 7

When comparing ultrasonic leak detection to soap bubble testing for compressed air system leaks, the primary advantage of ultrasonic detection is:

Accepted Answer

Ability to locate leaks while the system is pressurized and operating

Answer

Lower equipment cost

Answer

More accurate flow rate quantification

Answer

Better sensitivity to very large leaks