CET Roping & Counterweight Systems Flashcards
6 cards from real CET practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 CET Roping & Counterweight Systems flashcards as text
What is the visual inspection criterion that indicates an elevator hoist rope should be removed from service?
Answer: Six or more broken wires per rope lay or three or more broken wires in one strand
ASME A17.1 specifies that hoist ropes with six or more broken wires in one rope lay, or three or more in one strand, must be removed from service.
What effect do worn sheave grooves have on elevator hoist rope life?
Answer: Reduce contact area and cause rapid rope fatigue and wear
Worn or corrugated sheave grooves concentrate rope stress on fewer wires, dramatically accelerating fatigue and shortening rope service life.
What is the purpose of 'rope clips' (Crosby clips) when used on elevator hoist rope installations?
Answer: Used for temporary field connections during rope installation or adjustment only
Rope clips are a temporary field tool used only during rope installation and adjustment, never as permanent load-bearing hoist rope terminations on elevators.
What is the function of the 'rope hitch plate' (rope shackle or dead end hitch) on an elevator?
Answer: Provides the adjustable termination point where hoist ropes attach to the car or counterweight frame
The hitch plate is the structural anchor point at the car or counterweight where each hoist rope terminates with an adjustable threaded shackle for tension equalization.
Why must counterweight clearances be verified whenever new rope is installed on a traction elevator?
Answer: New rope stretches during run-in, lowering the counterweight position and reducing pit clearance
New hoist ropes stretch during initial operation; if not accounted for, the counterweight may descend lower than designed, reducing the required pit buffer clearance.
What is the primary reason elevator hoist ropes are lubricated at the factory?
Answer: To protect wire strands from corrosion and reduce internal friction during bending
Factory lubrication penetrates the rope core and wire interstices to prevent internal corrosion and reduce metal-to-metal friction as the rope bends over sheaves during service.