I Practice Exam Questions And Correct

Machinery Lubrication Technician Level I Practice Exam Questions And Correct Answers (Verified Answers) Plus Rationales 2026 Q&A | Instant Download Pdf

• What is the primary purpose of lubrication in machinery?
• To increase friction
• To reduce friction and wear
• To cool the machine only
• To make noise

Rationale: Lubrication reduces friction and wear between moving parts,

which extends equipment life and improves efficiency.

• Which type of lubrication is typically used for slow-speed, heavily

loaded bearings?

• Hydrodynamic lubrication 1 / 4

• Grease lubrication
• Oil mist lubrication
• Boundary lubrication

Rationale: Grease is ideal for slow-speed, heavily loaded bearings because

it stays in place and provides a protective film.

• What does the viscosity of a lubricant measure?
• Color
• Flash point
• Resistance to flow
• Water content

Rationale: Viscosity is the measure of a fluid’s resistance to flow and

affects its ability to form a lubricating film.

• Which of the following is a sign of lubricant contamination?
• Clear color
• Water or metal particles in the lubricant
• Proper viscosity
• Low operating temperature

Rationale: Contamination, such as water or metal particles, can damage

equipment and reduce lubricant life.

• What type of oil is commonly used in high-temperature applications?
• Mineral oil
• Synthetic oil 2 / 4

• Water-based oil
• Diesel oil

Rationale: Synthetic oils have superior thermal stability and are better

suited for high-temperature conditions.

• Which method is used to determine the cleanliness of a lubricant?
• Viscosity test
• Particle count analysis
• Flash point test
• Acid number test

Rationale: Particle count analysis measures contamination levels in

lubricants and helps prevent wear.

• What is the primary function of an additive in a lubricant?
• Change color
• Increase density
• Enhance lubricant performance
• Reduce oil temperature

Rationale: Additives improve lubricant properties such as oxidation

resistance, corrosion protection, and wear reduction.

• Which type of bearing typically requires oil circulation for lubrication?
• Sleeve bearing
• Roller bearing 3 / 4

• Journal bearing
• Ball bearing

Rationale: Journal bearings require circulating oil to maintain a

hydrodynamic film and prevent metal-to-metal contact.

• What is the typical consequence of running machinery with low

lubricant levels?

• Increased efficiency
• Excessive wear or failure
• Reduced friction
• Longer lifespan

Rationale: Low lubricant levels can cause insufficient film formation,

leading to increased friction, wear, and potential equipment failure.

• Which lubricant property is most critical in high-speed

machinery?

• Color
• Viscosity
• Odor
• Pour point

Rationale: Viscosity ensures proper film thickness at operating speeds,

which is critical to preventing wear.

• What does “flash point” of a lubricant indicate?
• Freezing point
• / 4