CLS Lubricant Selection & Management 2

Question 1

A high-speed spindle bearing operates at 25,000 RPM with a light radial load. Which grease consistency grade is most appropriate?

Accepted Answer

NLGI 0

Answer

Lighter NLGI grades (0 or 1) are preferred for high-speed applications because they offer lower churning resistance and better flow to the bearing.

Question 2

Which base oil property most directly determines the suitability of a lubricant for low-temperature start-up conditions?

Accepted Answer

Pour Point

Answer

Pour point is the lowest temperature at which an oil flows, making it the key indicator for cold-start lubricant selection.

Question 3

A food-processing facility requires a lubricant for incidental food contact. Which lubricant designation is required by USDA/NSF?

Accepted Answer

H1

Answer

NSF H1 lubricants are approved for incidental food contact and are required wherever accidental contact with food is possible.

Question 4

When selecting a compressor oil for a reciprocating air compressor, which property is critical to prevent deposit formation and fire risk?

Accepted Answer

Low Carbon Residue

Answer

Low carbon residue (Conradson or Ramsbottom test) minimizes deposit buildup in hot discharge zones, reducing fire and explosion risk.

Question 5

A lubricant's 'R&O' designation indicates it contains which additive package?

Accepted Answer

Rust inhibitors and oxidation inhibitors only

Answer

R&O oils contain rust inhibitors and oxidation inhibitors, making them suitable for circulating systems and turbines without EP additives.

(CLS) Certified Lubrication Specialist Practice Test