NCCCO Wire Rope Inspection and Replacement Criteria 2

Question 1

How many visible broken wires in one rope lay length require wire rope replacement on a running rope?

Accepted Answer

6 or more broken wires in one lay, or 3 in one strand

Answer

ASME B30.5 requires replacement when there are 6 randomly distributed broken wires in one lay length, or 3 broken wires in one strand. Different standards may apply to standing ropes.

Question 2

What is 'rope lay length' and how is it measured?

Accepted Answer

The distance along the rope for one complete helical wrap of one strand around the core — typically measured by marking a strand and finding where it returns to the same position

Answer

One rope lay is the distance along the rope in which a single strand makes one complete revolution around the core. This is the inspection unit for counting broken wires.

Question 3

A wire rope shows a diameter reduction of 5% from its original diameter. What does this indicate?

Accepted Answer

Significant internal wear, corrosion, or core degradation requiring investigation and likely replacement

Answer

Diameter reduction indicates internal problems: broken core wires, internal corrosion, or compression wear. Even without visible external damage, diameter reduction signals serious degradation.

Question 4

What does heat damage look like on wire rope and why is it serious?

Accepted Answer

Discoloration (blue, brown, or black), distortion, or annealing of wires that permanently reduces strength

Answer

Heat from friction, welding, or fire anneals the wire, reducing its tensile strength. Even without visible damage, heat-affected rope may have lost significant load-bearing capacity.

Question 5

How should wire rope be stored when not in use?

Accepted Answer

On a reel in a dry, ventilated area, protected from moisture, chemicals, and physical damage

Answer

Proper storage prevents corrosion and physical damage: keep on a reel (prevents kinks), in a dry location (prevents corrosion), with ventilation (prevents moisture buildup), and protected from chemicals.

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

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

NCCCO Wire Rope Inspection and Replacement Criteria 2