What formula is used to determine the weight each crane is holding in a multiple crane lift?

The formula used to determine the weight each crane is holding in a multiple crane lift is based on the proportional distribution of the total load weight according to the distances of each crane from the load’s center of gravity. The correct formula for determining the weight held by the first crane is expressed as [B / (A+B)] x Load Weight, which calculates the fraction of the total load weight that crane one supports based on the lever arm length, or distance, to the center of gravity.

In this context, "A" represents the distance from crane two to the center of gravity, while "B" represents the distance from crane one to the center of gravity. The denominator, (A+B), sums these distances to determine the total effective lever arm length. By dividing B by (A+B), the formula appropriately weights the contribution of crane one relative to the total distance, ensuring a proper distribution of the load.

This calculation is crucial in multiple crane lifts because it ensures stability and balance, preventing hazards associated with uneven weight distribution. Properly understanding this formula enables rigger professionals to plan and execute safe lifting operations in scenarios involving multiple cranes.