Although a broad range of models is available, the most significant for Australia are the 7-tonne CC224 and the 10.5t CC424. The new range is significant in being the first launched since Atlas Copco bought Dynapac, providing it with secure long-term ownership after seven years of ownership changes. There are other significant changes to the product line-up in the pipeline.The new range also marks the first large-scale use of electronics in Dynapac machines, and the PLC hydraulic pump control has enabled some significant improvements in operation. One of those is being able to set the top speed of the roller (infinitely variable) such that the joystick control will only accelerate the roller to the preselected top speed. Soft starting and stopping is also a feature to protect the asphalt surface, and a safety feature is that rapid movement of the stick is detected and brings the roller to an immediate halt, providing an alternative to the separate emergency stop button.The operator seat can be moved across the full width of the cab and rotated through 180 degrees so that the operator can view the outside of the drum. All controls now move with the seat, and there is a new LCD control panel.A choice of enclosed cab and open ROPS cab is offered, with the 4-post ROPS cab having narrow pillars that minimise the intrusion into the operator’s sight lines.Economy has been improved with an automatic idle feature and thermostatically controlled fans. There is a choice of engine power for each model, with Tier 3 Cummins QSB engines fitted throughout the range. Serviceability has also been addressed with service points located on one side, use of a maintenance-free steering hitch and cylinder, extended service intervals, use of short hoses from each drum to a bulkhead to simplify hose replacement and the ability to replace drum shock absorbers without removing the forks or drums. Service information is displayed on the LCD panel.Each roller has a high frequency/low amplitude setting for thin asphalt layers and a high amplitude for thick layers. Dynapac also states that these rollers are very effective in compacting roadbase with high moisture and good fines content.The water system has had significant changes, with a single large tank mounted in the chassis rather than having smaller tanks above each roller.This has allowed standard water capacity to be increased to 750 litres on the CC224 and 900 litres on the CC424 (generally avoiding the need to refill during a shift), and the operator now has a clear view of the drum, drum edges and spraybar.If required, an additional, independent spray system can be fitted with a second spraybar on each drum and tanks above the drums for increased capacity, but there should be few circumstances where this is required.
