Liebherr EC-B flat-top head and cabin
Since delivery of the first order during autumn 2004, more than 100 42 K.1 cranes have already left Liebherr’s production facilities in Biberach. Fast-erecting cranes are being used more and more frequently on bridge construction sites and for building residential houses.
The EC-B flat-top has a redesigned crane cabin, which is interchangeable for EC-B cranes up to 130 mt and which is attached and detached using quick-release fastenings. With the large EC-B cranes from 140 mt upwards, the cabin is configured to be retracted for transport. There are a total of 14 cranes with lifting capacities from 50tm to 280tm.
The comfortable operator’s position inside the soundproofed and insulated cabin provides an unrestricted view of the working area, allowing each load to be positioned optimally. The control panels for all functions are built into the seat and offer numerous adjustments. EC-B Flat-Top cranes of 140 mt and above are fitted as standard with the EMS electronic monitoring system. Air conditioning can be fitted as an option.
EC-B series Flat-Top cranes are built according to a modular concept. This ensures that tower systems within the series are compatible. The jibs are designed in such a way that many of their segments can be combined within the individual crane families.
The newly designed counter-jib can be pre-assembled on the ground in only a few steps. Auxiliary mounts of a new type are provided for positioning the counter-jib guying. Assembly is also simplified by the guying system, which is already located precisely in the assembly position, as well as the lifting lugs for lifting by the mobile crane. Thanks to the reduced weight of the individual transport units, small mobile cranes can be used for lifting. Quick release fastenings and/or centre pins also facilitate bolting the jib and counter-jib into position.
With EC-B cranes up to 130 mt, the foldable handrails can be quickly erected. To further facilitate assembly, all the jib and type LC tower pins are integrated in a pin magazine.
A further novelty is the transportation position of the load hook for EC-B cranes up to 130 mt, which is now stowed for transport in the jib heel. During assembly, the hook is simply lowered by means of a crank, making cable reeving a very simple operation.
Only frequency converter drive units are used in EC-B crane slewing gears. The smaller 50 EC-B 5 and 63 EC-B 5 types use the EDC slewing gear. Convenience features such as smooth micro speed slewing of the crane and inbuilt anti-swing damping which minimises crane oscillations and swinging of the load, are now standard on almost all Liebherr top-slewing cranes. Wind and load influences are detected electronically and are automatically countered by compensating movements of the jib.
Customers are offered a choice of pole-changeable or frequency controlled versions for the hoist gear. Liebherr fits only its proven in-house built motors in the high performance one speed frequency controlled hoists. These hoists provide impressive, integrated automatic load compensation and wide power and speed ranges. The positioning mode permits the load to be suspended and held at zero slewing speed without activating the parking brake. This allows extremely subtle raising and lowering, the company says. A particularly high degree of safety is achieved by the motor management only being switched off once the brake has taken the full weight of the load.
The drive concept of the new EC-B cranes is complemented by Liebherr’s proven frequency controlled trolley gear, which ensures particularly subtle movements in all types within the series coupled with a high trolley speed.
