Crews use the LG 1750 crane to install the wind turbine’s blade socks.
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-ft. (122 m) hub height in the Lubbock, Texas, area.
Based in Pratt, Kan., Trand took delivery of the first LG 1750 in the United States in March. The LG 1750is an 850 ton- (771 t) 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 ft. (193 m) 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 lbs. (73,482 kg).
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.
Crews install a blade socks on a wind turbine that has a hub height of nearly 400 ft. (122 m).
"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 ft. (105 m) 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 ft. pre-bend and would likely have hit the boom using the original configuration."
The crane was sitting at a 110 ft. (33.5 m) radius and was able to easily remove and replace the rotor.
This crane also is stabilized on an outrigger system, which makes it safer than other cranes of similar size and capacity. Fast mobilization and easy assembly and disassembly are benefits Trand appreciates.
Including the LG 1750, Trand owns four Liebherr cranes — two LTM 1750-9.1 mobile cranes and an LTM 1300-6.2.
"We feel the LG 1750 is a great addition to our fleet to service the larger turbines that the current fleet cannot handle. We also plan to use it for plant work," said Arnett.
"The courtesy that Liebherr has shown us and our employees is above and beyond," Arnett said. "With this being a new crane in the United States, there were many obstacles we had to overcome to make it work for our company, and Liebherr has gone the extra mile to make those adjustments. The gestures they have shown us make you feel more confident in your purchase and make you realize what an honor it is to own a Liebherr crane.
"Liebherr cranes are considered best in class and we find this to be true. We feel Liebherr excels at looking at the needs for the industries these cranes are purchased to serve and then building components to help make this service more efficient. We are very happy with each purchase we have made from Liebherr. The service is beyond any other company."
Trand's overall fleet consists of 11 mobile cranes. This positions the company to serve the wind power industry, which is continually moving toward larger towers and heavier components. Founded in 1990, Trand specializes in wind industry, refinery and gas plant projects and employs 22 people.
For more information, visit www.liebherr.com.