Blade Removal and Replacement

Wind tower erection and maintenance are costly because they generally require the work of a large, expensive crawler crane. Using a craneless single blade solution, which provided a less expensive alternative, Barnhart removed and replaced a damaged 153- foot-long blade on a 2.5 megawatt C-96 Liberty wind turbine generator. This innovative approach was recognized with the 2015 SC&RA Rigging Job of the Year under $150,000. The system conceptualized, engineered and designed by Barnhart was built to be used multiple times for this turbine platform. It included a blade lifting beam based on a spreader bar concept with a pioneering fully articulating dual sheave lifting point. The load line was routed from a winch truck (an over-the-road tractor modified to accept a winch commonly found on a 100-ton RT) through the nacelle, around the gearbox, into the hub and connected to the blade lifting beam. The winch was mounted to a rotex bearing, giving the operator the ability to line up the cable. Barnhart utilized their Multi-Tagline Device to safely perform the lift of the blade. It consisted of three winches which operated independently to control eight taglines, and collectively to achieve the control needed. Additional weight created by ice buildup on the blade posed a challenge that Barnhart met by employing a "steam genie" to melt the ice and perform the exchange.