These high frequency compactors can keep pace with pavers moving at faster speeds, assist in reaching target densities in higher temperature zones and allow fine-tuning of drum energy for differing materials and changing conditions through eight-amplitude technology exclusive to Volvo. With the eight amplitudes, operators can adjust to the right setting for the material to achieve the required density without worrying about fracturing aggregate particles in the mix.
Both compactors employ the SMART start system, available only on Volvo compactors. A consistent mat quality and density is achieved through this system. The lead drum vibrates first and the trailing drum begins to vibrate at the same place as the lead drum.
Another Volvo design component is chamfered, radiused edges on the drums. This minimizes drum marking and maintains smooth surfaces as the roller makes its passes.
The Volvo patented impact meter measures the relationship between the compactor™s vibration frequency and its rolling speed to accurately indicate the number of drum impacts per foot. The operator is able to precisely control the optimal rolling speed for the desired drum impact spacing using an easy-to-read, color-coded gauge. This system allows for increased productivity under a wider range of operating conditions.
The industry™s best drum wetting system is available on both models. Volvo has a dual water spray system that incorporates primary and secondary spray components. Each drum has an independent water storage tank and two water pumps, two primary filters, separate water distribution lines and two spray bars with hand-serviceable nozzles. Better drum surface coverage and reduced misting is achieved with 10 nozzles on each DD118HA spray bar; the DD138HA spray bars are fitted with 12 nozzles each. Two 164-gallon (620-liter) water tanks are monitored by the illuminated water level indicator.
The DD118HF has a Cummins four-cylinder engine and the DD138HF has a Cummins six-cylinder engine. Both engines are turbocharged and charge air-cooled. Hydrostatic direct drive of both drums provides enhanced gradeability and traction.
The DD118HF has a vibration frequency of 3,400 vibrations per minute (56.67 hertz), an industry-leading maximum centrifugal force of 42,680 pounds (190 kilonewtons) and a maximum nominal amplitude of 0.025 inches (0.63 millimeters). The machine has an operating weight of 27,670 pounds (12548 kilograms). The DD118HF is 236 inches (5995 millimeters) long, 87 inches (2210 millimeters) wide and has a height of 124.4 inches (3160 millimeters) to the top of the ROPS / FOPS.
The DD138HF has a vibration frequency of 3,200 vibrations per minute (53.3 hertz), a maximum centrifugal force of 42,260 pounds (188 kilonewtons) and a maximum nominal amplitude of 0.025 inches (0.63 millimeters). The machine has an operating weight of 30,325 pounds (13752 kilograms). The DD138HF is 236 inches (5995 millimeters) long, 92 inches (2337 millimeters) wide and has a height of 125.2 inches (3179 millimeters) to the top of the ROPS / FOPS.
Operators of both compactors will spend less time on daily maintenance and more time on production because service points are accessible from the ground level. The engine compartment hood is made of a single-piece composite structure that is hinged at the rear for easy access. This hood design provides unobstructed access to the engine for easy daily maintenance.