A Liebherr LG 1750 provided the primary lifting power for Trand, Inc., during a nearly two week long project in May. The company provided crane services for a main shaft exchange on a wind turbine with a nearly 400 foot hub height in the Lubbock, TX area.
Based in Pratt, KS, Trand took delivery of the first LG 1750 in the U.S. in March. The LG 1750 is an 850 ton-class eight axle, lattice boom mobile crane with the mobility of a drivable carrier and the lifting capacity of a crawler crane. It has a 633 foot maximum hoist height, six winches and variable boom systems. Among other items, the crane handled a gearbox assembly and its heaviest lift was 162,000 pounds.
Under the leadership of Trand President Terry D. Arnett, vice president of operations Andrea D. Arnett, crane operator Ken Cornelson, Jr. and rigger and oiler Patrick Petersen, all of the LG 1750’s standard features, combined with some additional equipment, helped the project get done safely, efficiently and on schedule, the company said.
“One challenge we faced during the planning of this job was that the allowable ground bearing pressure was very low,” said Andrea Arnett. “At the time of the crane purchase, we also purchased eight steel mats to help spread the pressure over a larger area and minimize the pressure per square foot to the ground. The steel mats were essential for this job.”
The strength of the LG 1750 on this job was its lifting capacity and luffing abilities. Trand also purchased a 344 foot luffing jib with the crane. “The luffer was essential for this job,” Arnett said. “We originally did not plan to use it, but the blades on this rotor had a 40 foot pre-bend and would likely have hit the boom using the original configuration.”
Crews install a blade socks on a wind turbine that has a hub height of nearly 400 feet.