Mercedes-Benz Unimog's exciting new role in forestry

By Colin Windell

 

Overcoming the challenges of narrow roads sometimes both steep and slippery and then manoeuvring the equipment needed for operations can be a headache for forestry operators – but, at a recent show in Germany, Mercedes-Benz presented solutions using the Unimog.

This forestry all-rounder is tailor-made for year-round use by municipal forestry departments, private forest owners, forestry managers and contractors.

The Interforst show is the leading international fair for the forestry sector. At four-year intervals, it presents future-oriented solutions for the entire timber and forestry sector. In 2018, a total of 451 exhibitors displayed their products.

Three highlight exhibits of the Unimog implement carrier series showed the great bandwidth and flexibility of the Unimog in forestry applications.

On display at the 2018 Interforst show were a Unimog U 529 with a two-axle tandem push-trailer by Fliegl and a Unimog U 530 with long wheelbase equipped with a front-mounted chipper by Schliesing Machinery GmbH; its cable winch and high-level bucket loader are by Fahrzeugbau Huber GmbH in Chemnitz.

Also presented was a Unimog U 530 with a height-adjustable cab by Werner Forst- und Industrietechnik GmbH. This is for professional operation of the body-mounted crane and the towed chipper by Jenz Maschinen- und Fahrzeugbau with which it was equipped.

As a universal, professional implement carrier with a high payload and towing capacity, the Unimog takes care of a wide variety of applications related to forest management.

In the spring it helps to maintain paths, in the summer it maintains wooded and green areas, in the autumn it chops timber and in the winter it clears the roads and paths. Its compact dimensions make it particularly manoeuvrable – an important criterion when things get tight during the care and maintenance of forests, grassed areas and networks of paths.

Auxiliary rear axle steering is available to reduce the already small turning circle by a further 20% or so, which further improves manoeuvrability.

Thanks to its fast road speed of up to 80 km/h, the Unimog is always quick to get where it is needed. At the same time, its outstanding off-road capabilities ensure good progress even on difficult terrain.

The Unimog has four implement mounting spaces at the front and rear, between the axles and on the chassis, allowing installation of quickly demountable implements and superstructures. This means the all-rounder can also take on other jobs whenever nothing needs doing in the forests. During this ‘forestry off-season’, it can also be used for other tasks such as mowing assignments.

Its high overall cost-effectiveness in year-round operation is in part due to the low fuel consumption and long maintenance intervals of 1 400 operating hours.

One of the vehicles on display was a Unimog U 530 L with long wheelbase (3 900 mm) and equipped with a front-mounted chipper by Schliesing Machinery GmbH in Kempen.

This vehicle not only scores in the forestry sector, but can also be used in gardening and landscaping, waste disposal, for intermediate transport duties and to load bulk containers. The shredded material can be filled into the permanently installed, side-tipper body without any other aids. Towing an additional trailer is possible without restrictions.

The implement combination on display is suitable for all working applications in the forestry sector that require the use of several implements. Whether used for regular timber cutting, timber harvesting or road/path clearance applications, or whether the combination is used as a compact and efficient unit to carry out gardening/landscaping/construction work, all the components in this vehicle solution are optimally coordinated.

With its all-wheel drive, power take-off and power hydraulics, the Unimog U 530 provides the perfect basis for the high-level bucket loader. The high-level bucket loader has a basic load capacity of 15 cubic metres, which can be increased to 55 cubic metres in combination with a trailer. The front-mounted chipper has a 340 mm wide mouth, and can process trunks with a diameter of up to 300 mm. When dragging timber, the cable drum at the rear gives the cable winch a 250° operating range and can be remote controlled. The cable length of 60 metres with a diameter of 12 millimetres provides adequate scope for this.

A high power output is required to operate mounted implements such as the Jenz chipper, which has a very high power requirement for its drum and feeder. This is provided by the rear power take-off of the most powerful Unimog engine variant: the 7,7-litre OM 936 engine of the Unimog U 530 delivers 220 kW.

The wheelbase of the Unimog is 3 350 mm, ensuring great manoeuvrability when negotiating forested areas where access is often difficult. This advantage also comes into its own during slow manoeuvring, when the chipper has to be positioned precisely in confined spaces.

The height-adjustable cab was realised by Werner Forst- und Industrietechnik GmbH: thanks to its all-round view of the entire working area, it allows professional operation of the towed HEM 583 Z chipper with body-mounted crane and tree gripper.

The compact special body is able to process trunks with a diameter of up to 56 cm − or several trunks at once − without difficulty. They are fed into the mouth of the chipper by the tree gripper. The crane is powered by the Unimog’s hydraulics as required.

During chipper operations in the forest and on the road, the Unimog U 530 benefits from its high road speed of up to 80 km/h when making transfer journeys from A to B. In the driver’s cab, large window areas at the front and sides provide outstanding visibility, while sound encapsulation ensures a low noise level.

A chip off the old block perhaps!