Long search off road
08 May 2008
After a long period of searching, Danish company Vestjyske Net Service has found a new solution to fulfil its truck-mounted loader requirement. Vestjyske Net Service is responsible for maintenance of the high-voltage electricity network in Denmark over a 7700 km2 area.
Peter Svendsen, a line assistant at VNS, explains that following the research period that started in 1998, it was clear the company needed an off-road four wheel drive truck that could drive almost anywhere. The loader had to be bigger with a higher reach than existing HMF loaders when fitted with a personnel basket. The project was paused for a period as it was proving difficult to find the correct wheel type for the truck.
In the meantime, the Odin and Thor loaders from Danish loader manufacturer HMF were launched, which meant a heavy duty HMF loader is now available that could achieve the required reach with a personnel basket.
VNS bought a special purpose Mercedes Actros truck with four axles, drive to all wheels and two sets of single wheels. One set of wheels (size 445/65 22.5) is for driving on public roads and the second set (wide wheels) is for traction off road.
The vehicle body has an HMF loader sub-frame mounted as a tipping body, or lift system, and no additional chassis or subframe reinforcement is required. The sub-frame is designed at the rear end so that the fifth wheel is not placed too high, and the rear stabiliser beam is fabricated to the sub-frame so the truck serves as a counterweight.
The crane is an HMF Odin type OK6 with a 1200 K6 fly jib. The crane's maximum lifting moment is 52.4 tonne-metres, and thanks to an optimised boom system, the loader boasts a vertical reach of 34.5 m. The specification includes 15 degree over-bending on the extension and 19 degrees over-bending on the fly jib. Also fitted is Scanreco remote control with the HMF InfoCenter feature, which indicates information that includes; percentage load, hydraulic oil temperature, load weight (if a weighing cell is mounted), the cause of a loader stop, battery status, etc. In addition, hose reels are mounted on the rear stabiliser leg so the hoses do not hang down when the stabiliser legs are completely retracted.
Also fitted is the EVS (Electronic Vehicle Stability) system - equipment required by the authorities for lifting with a personnel basket. HMF loaders with EVS have electronic heel sensors that constantly monitor and determine the lateral and longitudinal heel of the vehicle in fractions of degrees. As soon as the vehicle starts to heel, an alarm sounds. If the operator ignores the alarm, the EVS stops the crane before the load moment reaches the critical limit area and only allows movements that reduce load moment.
The stability system is designed to ensure vehicle stability even if the stabilisers are not completely extended or if they are not in contact with the ground, which is often the case when repairing high-voltage electricity lines.