Mechanical Systems & Equipment Maintenance Flashcards

Which type of bearing is best suited for handling both radial and axial (thrust) loads simultaneously?

Answer: Angular contact ball bearing

Angular contact ball bearings are designed to handle combined radial and axial loads due to their contact angle geometry.

When a V-belt drive shows signs of slipping under load, the FIRST corrective action should be:

Answer: Adjust center distance to increase belt tension

Adjusting the center distance to restore proper tension is the first step before considering replacement or other measures.

A pump cavitates when the fluid pressure at the inlet falls below the liquid's:

Answer: Vapor pressure

Cavitation occurs when inlet pressure drops below the fluid's vapor pressure, causing vapor bubbles to form and collapse.

What is the primary purpose of a mechanical seal in a centrifugal pump?

Answer: To prevent fluid leakage along the shaft

Mechanical seals prevent process fluid from leaking out along the rotating pump shaft.

Which gear type produces the LEAST amount of noise during operation?

Answer: Helical gear

Helical gears have angled teeth that engage gradually, resulting in quieter and smoother operation than spur gears.

An infrared thermometer shows a motor bearing running at 210°F (99°C) when the ambient temperature is 75°F (24°C). This indicates:

Answer: Possible lubrication failure or overloading

A bearing temperature rise greater than 70°F above ambient typically signals lubrication failure, overloading, or misalignment.

What does a high vibration reading in the axial direction on a rotating machine most commonly indicate?

Answer: Misalignment

Axial vibration is the signature direction for angular or parallel misalignment in coupled rotating machinery.