Load Charts and Capacity Flashcards

When calculating load radius, the measurement is taken from the center of rotation to:

Answer: The center of the suspended load

Load radius is the horizontal distance from the center of rotation to the vertical centerline of the load.

Boom deflection under load tends to do what to the actual operating radius?

Answer: Increase it beyond the no-load radius

As the boom bends under load it moves the tip outward, increasing the real radius and lowering capacity.

If a load chart lists capacities for 'fully extended outriggers,' using mid-extended outriggers means you must:

Answer: Use the lower mid-extended capacity column instead

Reduced outrigger spread narrows the stability base, so a separate, lower capacity column applies.

A 360-degree (over-the-side) rating compared to an over-the-rear rating on a rough-terrain crane is usually:

Answer: Lower, because over-the-side is the least stable orientation

Over-the-side lifts are governed by the narrowest stability and therefore carry lower ratings.

What information does the 'range diagram' portion of crane documentation provide?

Answer: The relationship between boom length, boom angle, radius, and lift height

The range diagram shows how boom length and angle translate into radius and available lifting height.

If the planned lift exceeds the chart capacity at the required radius, the correct action is to:

Answer: Stop and reconfigure, use a larger crane, or reduce the load

Exceeding rated capacity is never permitted; the lift must be replanned with a different setup or machine.

The weight of an auxiliary lifting attachment such as a jib that is erected but not in use should be:

Answer: Deducted from the main boom's capacity as required by the chart notes

An erected jib, even when unused, adds weight that reduces main-boom capacity per the chart's deduction notes.