Traction Drive Systems and Wire Rope Flashcards

What type of rope construction is most commonly specified for traction elevator hoist ropes?

Answer: Independent wire rope core (IWRC) ropes

Independent wire rope core (IWRC) construction is commonly used for elevator hoist ropes because it provides greater fatigue resistance and load-bearing capacity than fiber core ropes.

How does a QEI inspector confirm that rope end connections (shackles) are properly secured on a traction elevator?

Answer: By visually inspecting for proper wedge seating, safety pins, and absence of cracks or deformation

Inspectors visually examine each shackle for proper wedge seating, intact cotter pins or safety fasteners, and freedom from cracks, corrosion, or deformation.

What is the purpose of a 'rope gripper' device in a traction elevator system?

Answer: To arrest the car by gripping the hoist ropes in the event of a rope slack or overspeed condition

A rope gripper is a safety device that clamps the hoist ropes to stop the car if rope slack or an overspeed condition is detected.

When inspecting a gearless traction machine, what component is directly responsible for creating stopping force?

Answer: The electromagnetic disc or drum brake mounted on the motor shaft

In a gearless machine, an electromagnetic disc or drum brake acts directly on the motor shaft to stop and hold the elevator car.

What should a QEI inspector do if a traction elevator's hoist rope shows evidence of kinking?

Answer: Remove the rope from service immediately as kinking permanently damages the rope structure

Kinking permanently deforms the wire rope's internal structure, creating a fatigue point that cannot be repaired, requiring immediate removal from service.

What does 'rope lay' refer to when evaluating wire rope condition on a traction elevator?

Answer: The length along the rope in which each wire strand completes one full helical twist

Rope lay is the distance along the rope axis over which one strand makes one complete helical wrap, used as the reference length when counting broken wires.