To eliminate the need for an investment in either a larger capacity crane or a second support crane to lift heavier booms on the job, Manitowoc Cranes developed the Boom Raise System for the 440-ton 16000 Wind Attachment.
Manitowoc says the new system is desinged to raise longer Wind Attachment boom lengths that are needed to install nacelles on 100-meter wind turbine towers withtout the need of an assist crane. Manitowoc introduced the Wind Attachment in 2010, increasing the capacity of a crane by nearly 50 percent at short radii.
Jerry Maloney, global product director at Manitowoc, says standard wind tower heights are rising from 80 meters (262 feet) to 100 meters (328 feet), requiring crane users to obtain not only an increase in capacity, but an increase in reach as well. This means longer, heavier booms. ?”The Boom Raise System provides the extra boost needed to raise the boom until the standard boom hoist system fully takes over,” Maloney says.
?The Boom Raise System allows end users to lift up to 351 feet of Wind Attachment Boom plus 25 feet of Extended Upper Boom Point. Previously, customers were limited to 301 feet plus the Extended Upper Boom Point. The maximum capacity with 351 feet of boom plus 25 feet of EUBP at a 65-foot operating radius is 96.8 tons.??
The Boom Raise System utilizes a large hydraulic cylinder housed in a special 10-foot boom insert section that attaches to the boom butt. The boom raising cylinder works in conjunction with the boom hoist by exerting an upward force on the boom. This is achieved by extending the cylinder downward onto prepared ground/matting. Once the boom angle is 38 degrees, the boom hoist fully takes over. ??
Boom raising and lowering operations are accomplished with little operator action. Before booming up, the cylinder must be manually extended by a switch in the operator’s cab to contact the ground/matting. From this point, the operator simply controls the boom hoist handle while the crane’s operating system automatically controls the Boom Raise System. After reaching a boom angle of 38 degrees, the cylinder must be manually retracted. The same steps are performed in reverse for boom lowering. ??