Manitowoc Model 31000 crawler crane has a lift capacity of 2,300 metric tons, yet with a ground-bearing pressure of only 15,000 pounds per square foot. That’s because the 31000 includes an innovative lift enhancer that automatically extends when more counterweight moment is needed during the lift. The Variable Position Counterweight (VPC) is mechanically locked to prevent inadvertent movement during operation. The system’s mechanical actuator is controlled by the crane’s control system and is deployed based on boom angle and applied load.