HD+ from Hamm: the heavy tandem roller with the "plus" factor

Hamm has already been successful with its HD series of articulated tandem rollers for years. Now, the Tirschenreuth–based company is expanding its product range in the field of articulated tandem rollers. The roller manufacturer has again realized numerous innovations in the design of its new 12 tonne and 14 tonne rollers and is presenting the industry with a radical new design of tandem roller, with unique visibility features, an extremely user-friendly operating concept and impressive performance data. The two machines are being launched onto the market with the designation "HD+".

The HD series of Hamm tandem rollers made its market debut almost 10 years ago, heralding a change in the trend for designing and building modern articulated tandem rollers. The innovative machines stood out visually due to a complete new design. This design allowed many functions to be realized that other tandem rollers simply could not offer at the time: for the first time ever, the driver had a clear view of the drum and could monitor the water sprinkling at any time. The HD series also set new standards in terms of its clear arrangement.

Unique visibility features

Hamm has remained true to these principles and has again set a new standard in terms of comfort and visibility with its HD+ tandem rollers. The XXL cabin provides a comfortable, ergonomically optimized workplace with hitherto unattained freedom of movement. In best Hamm tradition, the driver has a complete overview of the drums and water sprinkling from any seated position. A new adjusting mechanism allows the seat to be moved laterally all the way to the outer edge of the cabin and effortlessly rotated. If the driver sits at the cabin edge, he has an outstanding view of the edge of the drums and the area surrounding the machine. And in the dark, additional high-intensity lights illuminate the edge of the drums.

Operation self-explanatory

The newly designed dashboard is securely attached to the steering column. Consequently, it is in the driver's field of view from every seated position without impairing either his view or freedom of movement. Furthermore, the shape of the steering column makes it very easy for the driver to enter and exit the cabin. Operation is self-explanatory. The driver has control of all important operating data of the roller at all times thanks to a clear arrangement of the operating elements and displays with unequivocal symbols.

Improved handling characteristics

The HD+ series also has some new features to offer in terms of handling: the revised pivot assembly is now located beneath the cabin, virtually at the centre of the machine. This results in an extremely favourable load distribution. Consequently, driving stability is greatly improved, as is the quality of the paving. Impressions in the asphalt when compacting in bends or around roundabouts are now a thing of the past thanks to the even load distribution. Instead, surfaces with perfect evenness are quickly produced in just a few passes. The new pivot assembly has another advantage: in comparison with previous rollers in the HD series, the offset during crab steering has been almost doubled. This lends the tandem roller excellent manoeuvrability and provides plenty of clearance for processing edges neatly.

Additional comfort is also provided by the steering system, with only a few turns of the steering wheel being necessary to turn the roller. What's more, the driver can set the maximum speed on the display, so that the full deflection of the control lever corresponds exactly to this speed. When reversing, the automatic transmission provides for smooth braking and acceleration, resulting in even asphalt surfaces without bumps or dents.

Hammtronic included

Hamm equips all HD+ rollers with its "Hammtronic" machine control system as standard. This governs the speed of the diesel engine, for instance, to ensure that optimum performance is available at minimum consumption.

Another special feature of the Hamm machines with the "plus" factor: the frequency and amplitude of the vibratory drives can be independently adjusted in both drums. This allows the rollers to be precisely matched to the requirements of the asphalt. Hamm also offers an additional high-frequency version for the US market, where paving is carried out with a very high advance speed and the compaction has to be correspondingly fast.

3-m machine height simplifies transportation

The overall height of the heavy-duty rollers has been reduced to 3 m. This renders transportation easy, as well as work under bridges or projections. The new design also reduces the access height by 25 cm, making it easier for the driver to get in and out.

Greater productivity thanks to enlarged water tank

With a capacity of almost 1,200 l, the water tank of the HD+ provides sufficient water for compaction without having to stop to refill the tank. Ingenious details such as the ease with which the water tank can be emptied, the antifreeze injection system and the self-cleaning filter also facilitate day-to-day work and maintenance. All of these aspects ensure a high level of availability and productivity for the tandem rollers.

Clean engine technology on board

The modern water-cooled 4-cylinder in-line engine with common rail fuel-injection system has an output of 100 kW and naturally fulfils the exhaust emission requirements of EU Stage III and US EPA, Tier III, guaranteeing quiet and eco-friendly operation. Additionally, an intelligently designed air-routing solution keeps the waste heat of the engine away from the driver's cabin.

Technical details:

HD+ 120
Operating weight, CE: 12,900 kg
Drum width: 1.98 m
Engine output: 100 kW
Water tank:1,160 l

HD+ 140
Operating weight, CE: 13,820 kg
Drum width: 2.14 m
Engine output: 100 kW
Water tank: 1,160 l

The articulated tandem rollers are available in three versions:
As a vibratory roller (VV), as an oscillating roller (VO) and as a high-frequency version for the US market.