BOMAG’s hybrid asphalt compactor option

First published in bauma Preview - March 21, 2019

BOMAG claims fuel savings and efficiency gains for its new hydraulic hybrid compactor

BOMAG’s hybrid asphalt compactor is said to offer lower fuel consumption and running costs. The new BW 174 AP tandem roller features a hydraulic hybrid drive system that provides power for peak demand during operation. The machine’s diesel engine, hydraulic accumulator and compaction system are all integrated to provide high working efficiency.

The package combines diesel engine, hydraulic accumulator and the firm’s Asphalt Manager system. The hydraulic accumulator is designed to provide power for short-term peak loads, such as when the vibration system is activated. This has allowed the firm to power the machine with a Stage V compliant diesel rated at 56kW rather than the 75kW engine normally needed for a 10tonne class asphalt roller. This more compact engine needs only a diesel particulate filter (DPF) to meet emissions requirements, with no need for the additional and complex selective catalytic reduction (SCR) system, which also requires refills of AdBlue fluid. Using the smaller diesel helps lower fuel consumption and CO2 emissions by up to 20% and running costs are further lowered by the removal of the SCR system. The hydraulic hybrid accumulator provides up to 20kW of power and a torque of up to 100Nm for peak loads. The system is charged in overrun mode, recovering energy instead of consuming fuel.

In addition, the machine features BOMAG’s sophisticated Asphalt Manager compaction system, providing more precise control. This offers infinitely variable control of compaction forces and vibration can be accelerated from standstill with little energy requirement. According to the firm, the required frequency is achieved faster than with conventional vibration or oscillation systems. The stepless, adjustable exciter is said to ensure that the forces required for compaction are controlled automatically. Meanwhile the integration of the hybrid drive and compaction system ensures that vibration frequency is optimised even at high load factors.

According to BOMAG, the Asphalt Manager system boosts compaction forces by up to 20% compared to conventional machines and combined with the hybrid drive, this allows compaction densities to be achieved with fewer passes, boosting productivity. Fuel consumption is further reduced to the Ecomode package. The Ecomode control unit processes data from various sensors and networks individual components. In addition to the engine and hydraulics, Ecomode now also steers the hybrid system. The BW 174 AP Hybrid also features the proven Ecostop idle speed cut-off, which ensures further fuel savings and reduces wear and tear.