NCCER Core Rigging Fundamentals & Material Handling 2 — Questions and Answers
Question 1: Which type of sling provides the best resistance to damage from sharp edges and high temperatures?
- Synthetic web sling
- Wire rope sling
- Chain sling (Correct answer)
- Round sling
Correct answer: Chain sling
Chain slings are the most resistant to heat and sharp edges because they are made of metal links that are not subject to cutting or melting like synthetic materials or wire rope.
Question 2: A wire rope sling should be removed from service if it has how many randomly distributed broken wires in one rope lay?
- 2 or more
- 6 or more (Correct answer)
- 10 or more
- 15 or more
Correct answer: 6 or more
ASME B30.9 standards require removing a wire rope sling from service if 6 or more broken wires are found in one rope lay length.
Question 3: What is the purpose of a spreader bar in a rigging operation?
- To increase the load's speed during lifting
- To keep sling legs from squeezing inward and damaging the load (Correct answer)
- To measure the distance between pick points
- To attach multiple loads to a single hook
Correct answer: To keep sling legs from squeezing inward and damaging the load
Spreader bars maintain the correct distance between sling attachment points, preventing the inward compression forces that could damage or crush the load.
Question 4: A synthetic web sling must be removed from service if it shows:
- Slight discoloration from UV exposure
- Acid or caustic burns (Correct answer)
- Minor surface scuffing on the label
- Stiffness from cold temperatures
Correct answer: Acid or caustic burns
Acid or caustic burns compromise the structural integrity of synthetic fibers and require the sling to be immediately removed from service and destroyed.
Question 5: What is a 'basket hitch' in rigging?
- A hitch where the sling is wrapped around a beam and both ends hook to the crane (Correct answer)
- A single-leg vertical attachment to a load
- A choker configuration with the sling wrapped around the load
- A method of attaching multiple slings end-to-end
Correct answer: A hitch where the sling is wrapped around a beam and both ends hook to the crane
A basket hitch passes the sling under the load with both ends attached to the lifting hook, supporting the load from below like a basket.
Question 6: What does 'D/d ratio' refer to in wire rope rigging?
- The diameter of the load compared to the distance of the lift
- The ratio of the sheave or pin diameter to the wire rope diameter (Correct answer)
- The derating factor divided by the design factor
- The depth of the hook throat compared to the wire diameter
Correct answer: The ratio of the sheave or pin diameter to the wire rope diameter
The D/d ratio compares the diameter of the sheave, drum, or pin (D) to the wire rope diameter (d), and a higher ratio reduces bending stress and extends rope life.
Question 7: Before a lift, rigging personnel should determine the load's center of gravity in order to:
- Calculate the total rope length needed
- Ensure the load will hang level and stable (Correct answer)
- Determine the correct shackle size
- Decide how many workers are needed on the ground
Correct answer: Ensure the load will hang level and stable
Identifying the center of gravity ensures rigging attachment points are positioned correctly so the load hangs level, preventing uncontrolled tilting during the lift.
NCCER Core Rigging Fundamentals & Material Handling 2
Which type of sling provides the best resistance to damage from sharp edges and high temperatures?