The new mid-range tandem rollers with the “plus factor”

The compaction experts from the Wirtgen Group unveiled the mid-range offerings of this successful new series at bauma 2010. Munich played host to a selection of models (the range comprises ten in total) in the 9 and 11 tonne weight classes from the global market leader in this segment. Equipped with articulated joints, these impressive machines boast unique visibility, exceptional performance data and provide a comfortable operating environment.

The heavy-duty HD+ 120 and HD+ 140 articulated tandem rollers have already been available in Europe and the USA . Positive feedback from road construction companies testifies to their success. Hamm has used bauma to present the modern heavyweights in their “plus” variants for the first time at a German trade fair. At the same time, Hamm was adding a further chapter to this success story with the new HD+ 90 and HD+ 110 mid-range machines. The new 9 and 11 tonne tandem rollers are all-rounders, suited to motorway construction or other large spaces, such as city centres.

“The operator enjoys exceptional visibility from a very comfortable workplace in the compact rollers,” explained Dr. Axel Römer, Head of Research and Development at Hamm. By focusing on the operator and several new technical features, Hamm now has a range of powerful and modern mid-range HD+ machines that are ready for series production. The result is machines that construction companies will use to compact quickly and efficiently.

^{International awards for HD+}

Hamm has set new standards for compacting technology with the HD+. This is impressively underscored by conferment of the internationally renowned iF Design award 2010 in gold for the series and the red dot design award 2010. Both prizes take criteria such as processing, innovativeness, environmental compatibility, functionality and ergonomics into account.

Moreover, the HD+ has been nominated as one of three machines for the bauma innovation prize in the design category and thus is recognized as one of the most innovative exhibits at the fair.

Outstanding visibility

The new XXL cabs on the HD+ 90 and HD+ 110 greet the operator with an impressively spacious workspace right from the very beginning. A previously unavailable freedom to move and a comfortable, ergonomic workplace are provided for by the panoramic cabs. A simple adjustment mechanism allows the seat to move from side to side right up to the outer edges of the cab, while turning the seat is achieved effortlessly. The driver is afforded an exceptional view of the drum edge and the area around the machine on all sides. Every seat position allows the drums and water sprinkling to be observed without restriction. Powerful lights illuminate the drum edges at night.

Intuitive operation

The problem of where to locate the control panel has been cleverly solved. Permanently attached to the steering column, it is always in the operator’s field of vision, regardless of the seat position, and does not affect his visibility or freedom to move in any way. The design of the steering column also makes getting in and out extremely easy. Compacting is carried out effortlessly thanks to intuitive controls and an overview of all the important operating data using clear symbols.

Integrated Hammtronic

Hamm is equipping all its “mid-range rollers with the plus factor” with the “Hammtronic” machine control system. It regulates the speed of the diesel engine, for example, so that optimum levels of performance are achieved with minimal fuel consumption. The machine management system also guarantees consistent and high-quality compacting results by controlling the drive and vibration drive.

Improved driving and steering characteristics

The developers have also improved the driving and steering characteristics. The mid-range machines now employ the three-point articulated joint principle. The articulated joint on the HD+ is located virtually in the centre of the machine. This results in an almost ideal weight and load distribution, leading to clear gains in directional stability and the quality of the finished road surface. The HD+ 90/HD+ 110 are especially suited for compacting in bends or roundabouts to produce perfectly flat surfaces. Equally impressive is the freedom of movement enjoyed by the new tandem rollers owing to the decision by Hamm to virtually double the offset with crab steering. As a result the driver has the tools at his disposal for neat edge processing.

Turning similarly becomes far easier as just a few turns of the wheel can completely alter the direction of the roller. The driver also benefits from the pre-adjustment feature for maximum speed. The drive lever can be in any position, yet the selected maximum speed will not be exceeded. During reversing manoeuvres, the automatic system ensures gentle braking and accelerating, leading to smooth asphalt courses with no bulges or depressions.

Adjust frequency and amplitude independently in both drums

A Hamm exclusive - the frequency and amplitude settings of the vibration drives can be adjusted independent of each other. This allows for adjustment of the parameters in both roller drums to meet the exact demands of the asphalt. An additional high-frequency model is available for the American market, where compacting is carried out at very high speeds.

Enlarged water tank, increased productivity

The large water tank holds enough water for an entire day’s work, eliminating refilling stops. Clever features such as easy water tank drainage, anti-freeze injection and self-cleaning filters simplify day-to-day work and maintenance. These aspects combine to provide high levels of availability and productivity from the tandem rollers.

Clean on-board engine technology

The water-cooled 4-cylinder in-line engine and its common-rail injection system deliver 100 kW of power, and conform to the requirements of EU level III and US-EPA tier III. This ensures quiet, environmentally-friendly operation. The intelligently designed air duct system also diverts the heat from the engine away from the driver's cab.

Technical data

The articulated tandem rollers are available in different versions: a vibration roller (W), an oscillation roller (VO), a combination roller (VT) and a high-frequency version for the US market (VV-HV). The HD+ 90 will also be available with separate roller drums as a vibration machine (W-S) and as an oscillation machine (VO-S).