Mechanical Power Transmission Flashcards
7 cards from real SACA practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Mechanical Power Transmission flashcards as text
A chain drive operates at high speed and begins producing significant noise and vibration. Which maintenance action should be checked FIRST?
Answer: Check and adjust chain tension and lubrication
Noise and vibration in chain drives most commonly result from improper tension (too loose or too tight) or inadequate lubrication — both should be checked first.
What is the function of a torque limiter (slip clutch) in a mechanical power transmission system?
Answer: To disconnect the load when torque exceeds a preset value, protecting equipment
A torque limiter automatically disengages or slips when torque exceeds its set point, protecting downstream components from overload damage.
Which bearing type is best suited for applications with both radial and axial (thrust) loads simultaneously?
Answer: Deep groove ball bearing
Deep groove ball bearings can handle combined radial and moderate axial loads, making them the most versatile and commonly used bearing type.
In a helical gear pair, why does axial thrust force develop?
Answer: Because the angled tooth helix generates a force component along the shaft axis during meshing
The helical tooth angle causes the mesh force to have an axial component proportional to the helix angle's tangent, requiring thrust bearings to react this force.
What is the primary advantage of a toothed (synchronous) belt over a standard V-belt in a precision positioning application?
Answer: No slip between belt and pulley, providing accurate speed and position synchronization
Synchronous belts have teeth that mesh with pulley grooves, eliminating slip and providing a precise 1:1 relationship between input and output rotation.
A gearbox nameplate states an L10 bearing life of 20,000 hours. What does L10 life mean in this context?
Answer: 10% of identical bearings will fail before 20,000 hours of operation
L10 (or B10) life is the time at which 10% of a large population of identical bearings would be expected to fail, meaning 90% survive to that point.
When two meshing spur gears have different numbers of teeth, which property is the SAME for both gears?
Answer: Tooth pitch (diametral pitch or module)
Mating gears must have the same diametral pitch (or module in metric) for their teeth to mesh properly, even though their diameters and speeds differ.