System solution for challenging crane movements
KEB Complete system for revolving tower cranes
Zelmer Baumaschinen GmbH has operated in the revolving tower crane hire and service sector since 1992 and is now working on a complete solution for particularly demanding tasks.
The owner-operated company has devised a new technical development gained from practical experience for top revolving cranes with permanent improvements, based on KEB core technology for drives and automation.
The aims of the new development are not only optimised movement properties but also coverage of the latest safety requirements, all translating into partnership collaboration with KEB as system supplier.
The tasks and solutions
The latest crane drive design of Zelmer Baumaschinen GmbH includes several KEB product ranges, offering a wide range of advantages for optimizing applications.
Zelmer Baumaschinen GmbH's "new crane drive development" project makes use of coordinated properties in the KEB portfolio with close collaboration in the technical sector to produce an optimised, individual customer solution.
1. Drive motors and magnet technology product group
Pictures: © Zelmer Baumaschinen GmbH
Travelling hoist drive**
Special slewing drive
COMBISTOP T with mircoswitch
Micro-switch for function and wear monitoring on lift drives for example.
Advantages of KEB mechanical components
- High quality, robust gear motor design
- Flexible adjustment to customer requirements, e.g. special paintwork, special shaft, external fan, junction box position for motor outputs, encoder system variants
- Specially designed gear motor with electromagnetically operated double-face spring-applied brake for the crane slewing gear. A special brake is incorporated for wind release in the gear motor line - brake action is spring-operated, with lifting by permanent magnets at evenings and weekends in the release position.
- The customer does not incur any additional costs for electromechanical devices for wind release of the jib.
- Integrated wear and function monitoring by microswitch
2. Digital drive technology product range - drive controller
The particularly compact design of KEB COMBIVERT F5 equipment forms the basis for an extremely compact control cabinet design at optimised cost.
Left side of control cabinet
Right side of control cabinet:
Pictures: © Zelmer Baumaschinen GmbH
Travelling hoist drive
Lifting and slewing gear
|22F5K1R-95DA||STO safety function and incremental encoder|
|20E6T60-3000||E6 EMC filter|
|16F5K1G-36DA||STO safety function and incremental encoder|
Advantages of KEB drive components
- Torque pre-control reduces the torque required for the tower movement from 80 Nm to 10Nm
- Increased dynamic acceleration and deceleration without the load swinging
- Reduction in angle of rotation without load from 45 degrees to 25 degrees and with maximum load torque of 60 degrees to 35 degrees. The angle of rotation is determined if the joystick is released at maximum speed and the speed drops to 0.
Here, the faster the better!
With the travelling hoist drive, the focus is on the dynamic handling and precise position approach at different speeds. A key feature here is the ASCL technology with encoderless regulation in the equipment, with reliable dynamic handling and precise positioning of the travelling hoist. Here again the 8 freely-programmable parameter sets ensure flexible adjustment of different load and speed profiles. As with the lifting and slewing gear, the travelling hoist drive is also monitored by an absolute safety encoder.
The lifting gear requirements are high dynamics, power and accuracy in a wide speed range up into the field-weakening range. These basic requirements can also be met here by a controlled drive with precise positioning of the position control in the drive and additional position monitoring by an absolute safety encoder in the safety PLC.
With the freely-programmable parameter sets in the COMBIVERT F5 the various different speed profiles can be made available.
Clean slewing gear processes are the hallmark of the entire crane and are the main focus of technical execution. The aim here was to combine smooth turning movements with no jerking or swinging of the load with precise position control.
The controlled KEB system achieves excellent results with the automatic calibration function amongst other things - three motors in the slewing gear are automatically calibrated together and monitored for speed during operation by an incremental encoder on one of the three slewing gear motors. The additional position monitoring function is provided by an absolute safety encoder, analysed by the safety PLC.