The measurement used to determine boom length is taken from the center of the boom pin to the center of which pin?

The measurement used to determine boom length is taken from the center of the boom pin to the center of which pin?

• A. Center of Rotation to Winch Drum
• B. End of Boom to Base
• C. Center of Boom Pin to Center of Sheave Pin
• D. Base to Tip

Answer: (C)

Boom length is defined by the distance between the center of the boom pin and the center of the sheave pin. This center-to-center measurement captures the true reach of the boom as it includes the actual load path through the end of the boom where the pulley block is attached, as well as the hardware thickness. Measuring to the winch drum, the end of the boom, or the base would not reflect the true functional length and could misrepresent the boom’s reach because those points don’t define the load-bearing geometry of the boom attachment and hoisting path.

Boom length is defined by the distance between the center of the boom pin and the center of the sheave pin. This center-to-center measurement captures the true reach of the boom as it includes the actual load path through the end of the boom where the pulley block is attached, as well as the hardware thickness. Measuring to the winch drum, the end of the boom, or the base would not reflect the true functional length and could misrepresent the boom’s reach because those points don’t define the load-bearing geometry of the boom attachment and hoisting path.