Which distance measurement identifies the distance from the boom hinge to the tip sheave pin?

• A. Boom Span
• B. Boom Radius
• C. Reach
• D. Boom Length

Answer: (D)

The distance from the boom hinge to the tip sheave pin is the length of the boom itself. This measurement, called the boom length, is the actual physical length along the boom from the hinge at the base to the end where the sheave pin sits. It stays constant for a given boom configuration, unlike other terms.

Boom span refers to the width between ends of the boom or supports, not the hinge-to-tip distance. Boom radius is the horizontal distance from the crane’s rotation center to the boom tip or load, which describes reach in plan but changes with boom angle. Reach describes how far the load can extend horizontally from the crane, also dependent on geometry and angle. So the correct term for the hinge-to-tip distance is boom length.