FLENDER gear units for slewing gears


Slewing gear drives are used to position driven machines. They have been tried and tested in many different applications, such as cranes, excavators, and drilling platforms. FLENDER gear units for slewing gear drives have a modular design. They can be combined with a long or short lantern gear drive on the output side. The mounted output pinions are manufactured according to the customer's specifications. On the input side, we offer solutions for both electric motors and high-speed or low-speed hydraulic motors, some of which are already standardised.

One frequently requested alternative, particularly as a gear unit for slewing gear drives in bucket wheel excavators, consists of a FLENDER planetary gear unit with a bevel or bevel helical gear unit on the input side. The drive motor and a brake are arranged on a bracket on the gear unit, so that the system no longer needs to be aligned on site. A brake is always mounted between the motor and the gear unit in order to fix the boom in a defined position. An overload safety mechanism can additionally be provided to protect the boom and the drive against inadmissibly high loads.

Technical data

  • Planetary gear unit

  • Nominal output torques from 22,000 to 354,000 Nm (higher torques available on request)

  • Transmission ratios from 25 to 4,000


  • Compact, space-saving design

  • Low weight

  • Low noise level

  • Variable lantern gear drive lengths acc. to customer's specification

  • Modular design creates increased flexibility and multiple mounting options

  • No need for on-site alignment thanks to bracket with motor, gear unit, brake, and coupling

  • Customised solutions for specific projects

  • Option of eccentric installation to enable the backlash to be adjusted between the pinion and the ring gear

  • Optimised sealing systems prolong the service life


  • Cranes

  • Excavators

  • Drilling platforms