CMRT Lubrication and Tribology Flashcards
6 cards from real CMRT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 CMRT Lubrication and Tribology flashcards as text
Which contamination type is considered the number one destroyer of lubricated components in industrial machinery?
Answer: Solid particle contamination
Solid particle contamination (dirt, wear debris, and dust) is recognized as the primary cause of lubricated component failures because particles accelerate wear and damage surfaces.
What does the ISO cleanliness code (e.g., ISO 16/14/11) measure in oil analysis?
Answer: The number of particles per milliliter at three different size thresholds
The ISO 4406 cleanliness code reports particle counts per milliliter at three size thresholds (4µm, 6µm, and 14µm), with each number representing a range of particle concentrations.
What is the primary advantage of using synthetic lubricants over conventional mineral oils in high-temperature applications?
Answer: Synthetic oils offer better oxidation stability and wider operating temperature ranges
Synthetic lubricants provide superior oxidation stability, thermal stability, and maintain useful viscosity across a wider temperature range compared to conventional mineral oils.
What is 'over-greasing' a bearing and why is it harmful?
Answer: Applying excessive grease that causes elevated temperatures, churning, and premature bearing failure
Over-greasing packs the bearing housing with excess grease, causing the rolling elements to churn the lubricant, generating heat, and ultimately leading to premature bearing failure.
Which property of a lubricant is described by its 'flash point'?
Answer: The lowest temperature at which the oil vaporizes sufficiently to ignite briefly when exposed to a flame
The flash point is the lowest temperature at which vapors above the oil will briefly ignite when exposed to an open flame, making it an important safety and fire-hazard indicator.
What does a rising trend of iron (Fe) particles in an oil analysis report most likely indicate?
Answer: Wear occurring in iron or steel components such as gears, bearings, or cylinder walls
A rising iron trend in oil analysis indicates that iron or steel components (gears, bearings, shafts) are experiencing abnormal wear, signaling a potential developing failure.