NCCCO Rigging Fundamentals and Hardware 2

Question 1

What effect does a sling angle have on the tension in each leg of a two-leg bridle sling?

Accepted Answer

As the sling angle decreases from vertical, each leg must carry more than the simple load share, increasing leg tension

Answer

As the sling angle decreases from vertical, leg tension decreases proportionally

Answer

Sling angle has no effect on leg tension if the load is evenly distributed

Answer

Leg tension is always equal to one-half the total load regardless of angle

Question 2

What does a wire rope sling's 'rated load' depend upon, and where is it specified?

Accepted Answer

Rated load depends on rope construction, diameter, configuration, and sling angle; it is specified on the sling identification tag and in manufacturer's data

Answer

Rated load depends only on the wire rope diameter and is specified in the OSHA regulations

Answer

Rated load depends only on the type of end termination and is specified by the rigging supervisor

Answer

Rated load is the same for all wire rope slings of equal length and is provided in the manufacturer's general catalog

Question 3

What is a shackle's 'working load limit' (WLL), and what marks must be present on a rated shackle?

Accepted Answer

WLL is the maximum load assigned by the manufacturer for the intended application; shackles must be marked with the manufacturer's name, WLL, and size

Answer

WLL is the maximum load the shackle can carry under ideal conditions; no marking is required on rated shackles

Answer

WLL equals the shackle's ultimate breaking strength divided by a factor of 10; only the WLL value needs to be marked

Answer

WLL is a theoretical value only; actual capacity must be determined by the rigging crew for each job

Question 4

When using a choker hitch with a synthetic web sling around a load with sharp edges, what protection must be used?

Accepted Answer

Corner protectors, padding, or edge guards must be used to protect the sling from cuts that can reduce its load capacity

Answer

Sharp edges require no special protection if the sling is rated for the full load weight

Answer

The sling should be doubled (two layers) to provide additional thickness at the edge contact point

Answer

Only wire rope slings may be used on loads with sharp edges; synthetic slings are never permitted

Question 5

A synthetic round sling has a blue colored core sleeve. According to ASME B30.9 color coding, what is its vertical hitch rated capacity range?

Accepted Answer

2,100 to 5,300 lbs

Answer

500 to 2,100 lbs

Answer

5,300 to 10,600 lbs

Answer

10,600 to 21,200 lbs

Question 6

What is the difference between a 'mechanical advantage' rigging system and a 'single line' rigging system?

Accepted Answer

A mechanical advantage system uses multiple parts of line (block and tackle) to reduce the tension in the hauling line; a single line applies the full load to one rope part

Answer

A single line uses only one piece of rigging hardware; a mechanical advantage system uses multiple pieces

Answer

A mechanical advantage system requires two cranes operating simultaneously; a single line requires only one crane

Answer

There is no practical difference; both systems place the same total tension on all components