NCCCO Rigging Fundamentals and Hardware

Question 1

What is the rated capacity of a wire rope sling used in a basket (U-wrap) configuration at an included angle of 120 degrees (60 degrees from vertical for each leg)?

Accepted Answer

Approximately 1.73 times the single-leg vertical capacity

Answer

Reduced to 50% of the single-leg vertical capacity

Answer

Equal to the single-leg vertical capacity regardless of angle

Answer

Doubled because two legs share the load

Question 2

A synthetic web sling is found to have a cut that has penetrated approximately 40% of the sling width. What is the correct action?

Accepted Answer

Remove the sling from service immediately — any cut penetrating the sling body is a removal criterion per ASME B30.9

Answer

Continue using it for lifts up to 60% of the rated capacity

Answer

Tape the cut with load-rated splicing tape and re-tag the sling

Answer

Use the sling in a choker configuration only

Question 3

When using a shackle in a rigging application, what is the correct orientation and securing method for the screw pin?

Accepted Answer

The pin should be fully seated and moused (safety wired or taped) to prevent rotation and backing out under load

Answer

The pin should face downward so gravity keeps it seated

Answer

The pin may face any direction as long as the shackle is rated for the load

Answer

The pin should be replaced with a bolt of equal diameter for permanent use

Question 4

What information is required on a wire rope sling's identification tag per ASME B30.9?

Accepted Answer

Manufacturer's name, rated capacity for each hitch type, and sling diameter or construction

Answer

Only the rated capacity in the choker configuration

Answer

The purchase date and inspection log number

Answer

The material grade and heat treatment code

Question 5

A rigger is sizing a wire rope sling for a straight vertical (single-leg) lift of a 10,000-lb structural beam. Which factor is most critical in selecting the sling?

Accepted Answer

The sling's rated capacity in the vertical hitch configuration must equal or exceed the total load weight

Answer

The sling color code matches the project specification

Answer

The sling diameter is equal to the crane hook throat opening

Answer

The sling length allows the load to be within 5 feet of the crane hook

Question 6

Under ASME B30.9, what is the minimum D/d ratio requirement for a wire rope sling passed around a pin or shackle?

Accepted Answer

D/d ratio of at least 5:1, where D is the diameter of the pin/shackle and d is the wire rope diameter

Answer

D/d ratio of at least 1:1 — any size contact point is acceptable

Answer

D/d ratio of at least 10:1 for loads over 10 tons only

Answer

No ratio requirement as long as the shackle is rated for the load