FREE NCCCO Wire Rope Inspection and Replacement Criteria Questions and Answers

Question 1

According to ASME B30.5, running rope on a mobile crane must be removed from service if there are how many broken wires in one lay?

Accepted Answer

6 randomly distributed broken wires in one lay

Answer

ASME B30.5 is a key safety standard for mobile cranes. It specifies that a running rope must be removed from service if there are 6 or more randomly distributed broken wires in one rope lay, or 3 or more broken wires in one strand in one rope lay. A 'lay' is the length of rope in which one strand makes a complete spiral around the rope core.

Question 2

What type of wire rope damage is characterized by a loop that has been pulled tight, resulting in permanent deformation and core damage?

Accepted Answer

Kinking

Answer

Kinking occurs when a loop is formed in the rope and then pulled tight, causing the wires and strands to be bent and deformed beyond their elastic limit. This permanently damages the rope's structure, significantly reduces its strength, and is a mandatory cause for removal from service.

Question 3

A reduction of the nominal rope diameter of more than what percentage is a cause for rope replacement?

Accepted Answer

5%

Answer

A noticeable reduction in rope diameter is a sign of internal damage, such as core failure, internal wire breaks, or excessive external wear. Most safety standards, including ASME, state that a reduction in the nominal diameter of more than 5% is cause for immediate removal from service.

Question 4

Which of the following is a clear visual indicator of heat damage to a wire rope?

Accepted Answer

Blue or rainbow discoloration of the wires

Answer

When wire rope is exposed to excessive heat, such as from a welding arc or lightning strike, the metal can be annealed, which severely reduces its strength. This damage is often visible as a blue, purple, or rainbow-like discoloration on the wires. Any rope showing such signs must be removed from service immediately.

Question 5

What is the term for the wire rope defect where the outer strands untwist and separate from the core, creating a cage-like appearance?

Accepted Answer

Bird caging

Answer

'Bird caging' is a specific type of rope failure typically caused by sudden load release (shock loading) or improper installation on a drum. The outer strands flare outwards, forming a shape that resembles a bird cage. This indicates severe structural damage and the rope must be taken out of service.

NCCCO (National Commission for the Certification of Crane Operators) Practice Test

NCCCO (National Commission for the Certification of Crane Operators) Practice Test

FREE NCCCO Wire Rope Inspection and Replacement Criteria Questions and Answers