Rigging and Hoisting Flashcards

What is a spreader bar (spreader beam) primarily used for in rigging?

Answer: To maintain sling leg separation and keep legs vertical, reducing compressive forces on the load

A spreader bar holds the sling attachment points apart so the sling legs remain near-vertical, preventing the inward compressive forces that angled slings would impose on a fragile load.

What is the standard CSA/ASME hand signal for 'hoist' given to a crane operator?

Answer: Index finger pointing upward with a circular motion of the hand and forearm

The standard hoist signal is an index finger pointed upward with the hand and forearm making a circular (winding) motion, mimicking the crane drum rotation.

What is the maximum fleet angle generally accepted for wire rope spooling onto a hoist drum?

Answer: 2° 30'

A maximum fleet angle of 2° 30' is the industry-accepted limit; exceeding it causes excessive rope wear, cross-winding on the drum, and premature rope failure.

When rigging a load with an off-centre (eccentric) centre of gravity, where must the crane hook be positioned?

Answer: Directly above the load's centre of gravity

The crane hook must be directly above the load's centre of gravity; any offset will cause the load to tilt until the CG hangs directly beneath the hook.

What does a proof load test on rigging hardware verify?

Answer: The hardware can withstand a load greater than its WLL without permanent deformation

A proof load test applies a load (typically 2× WLL) to verify the hardware will not permanently deform, confirming its rated capacity and structural integrity.

How should chain slings be stored when not in use?

Answer: Hung on a dedicated rack or peg to prevent kinking, tangling, and corrosion

Hanging chain slings on racks or pegs prevents kinking and tangling, allows drainage, and makes pre-use inspection fast and thorough.

What is the function of a load cell when used in a rigging operation?

Answer: To measure and display the actual tension force in the rigging during the lift

A load cell is an electronic force-measuring device inserted into the rigging that provides a real-time readout of the actual load being lifted.