Crane manufacturer Manitowoc has unveiled the Boom Raise System (BRS), which is designed for the 400 t Manitowoc 16000 Wind Attachment. The system aims to raise longer wind attachment boom lengths that are needed to install nacelles on 100-meter wind turbine towers, without requiring the use of an assist crane.
The BRS allows end users to lift up to 107 meters of wind attachment boom, plus 7.6 meters of extended upper-boom point (EUBP). Previously, customers were limited to 92 meters plus the EUBP. The maximum capacity with 107 meters of boom, plus 7.6 meters of EUBP at a 20-meter operating radius, is 87.9 metric tons.
The BRS utilizes a large hydraulic cylinder housed in a special three-meter 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 – which is achieved by extending the cylinder downward onto prepared ground/matting, Manitowoc explains, adding that once the boom angle is 38 degrees, the boom hoist fully takes over.
Boom raising and lowering operations are accomplished with minimal 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 BRS. After reaching a boom angle of 38 degrees, the cylinder must be manually retracted. The same steps are performed in reverse for boom lowering.
"Our goal in developing the Boom Raise System was to eliminate the need for investment in either a larger-capacity crane or a second support crane to lift heavier booms on the job," explains Jerry Maloney, global product director at Manitowoc Cranes. "The Boom Raise System provides the extra boost needed to raise the boom until the standard boom hoist system fully takes over."
Manitowoc has begun shipping this new option to Manitowoc 16000 crawler crane owners in North America and to export markets.