433A Rigging and Hoisting

Question 1

What does WLL stand for when marked on rigging equipment?

Accepted Answer

Working Load Limit

Answer

WLL stands for Working Load Limit, the maximum load a piece of rigging equipment is rated to lift under normal service conditions.

Question 2

Which hitch configuration provides the highest effective WLL when using a single-leg sling?

Accepted Answer

Basket hitch

Answer

A basket hitch supports the load on both sides of the sling, effectively doubling the rated capacity compared to a vertical (straight) hitch.

Question 3

When two sling legs form a 120° included angle, what is the approximate tension in each leg relative to the total load weight?

Accepted Answer

Equal to the total load weight

Answer

At a 120° included angle each leg is 60° from vertical, so tension per leg = W/(2 × cos 60°) = W/(2 × 0.5) = W, equalling the full load weight.

Question 4

What is the minimum number of wire rope clips (Crosby-type) required when forming an eye in 1/2" (13 mm) diameter wire rope?

Accepted Answer

3

Answer

CSA and manufacturer standards require a minimum of 3 wire rope clips for 1/2" rope to achieve the required connection efficiency.

Question 5

A synthetic web sling whose red warning core is visible through the outer jacket should be:

Accepted Answer

Removed from service immediately

Answer

An exposed red warning core indicates the sling outer jacket is critically worn; the sling must be removed from service immediately per CSA Z150 requirements.

Red Seal Millwright 433A Practice Test

Red Seal Millwright 433A Practice Test

433A Rigging and Hoisting