Slewing and swivelling drives are coaxial planetary gearboxes with two to four planetary stages, which drive large diameter bearings or gear rings via an output pinion. Both swivelling and slewing drives are made with short or long output shafts, depending on the installation situation. The one-piece, case hardened and ground output shaft withstands the highest loads and, if required, can be fitted with profile-corrected gearing. The optimum circumferential backlash is easily adjusted through the gearbox's optional eccentricity.
Slewing drives are employed in the slewing mechanisms of construction and mobile cranes as well as ship and offshore cranes. They are also used in rotor blade and yaw adjustment in wind turbines. Slewing gearboxes can be driven either electrically or hydraulically and are available in high gear ratios. If the installation space is restricted, a bevel gear can serve as an entry stage for a slewing drive. The installation position is variable, and can be vertical, horizontal or upside down. For extended operation times, for example when slewing drives power gear ring rope winches, external oil coolers can be provided.
Liebherr offers customers for slewing drives a standard range for a wide variety of applications. Tailor-made solutions can also be developed for special requirements.