MAN Engines debuts at bauma 2019 (Hall A4, 312) its new D4276 six-cylinder inline engine specially developed for heavy-duty off-highway machines and construction vehicles in particular.
With an output power between 450 and 515 kW (604 and 690 hp) depending on the power stage, this engine delivers a maximum torque of 3280 Nm already at 1100 r/min speed, which remains constant up to 1500 r/min.
The design is based on the D3876 engine range: “We are proud that we can offer our customers an engine that perfectly matches the requirements in the heavy-duty application field but at the same time combines all the advantages of the meticulously developed D3876 engine,” said Reiner Rößner, head of sales at MAN Engines.
The new 16.2-L unit has the same compact installation dimensions as the D3876: 1464 mm length, 978 mm width, and 1131 mm height. With a dry weight of just 1280 kg, this engine has a high power-to-weight ratio.
The development of the D4276 allowed to increase the displacement and modify the common-rail injection system. MAN said, the fuel flow has been significantly improved thanks to a newly developed high-pressure pump. An additional increase in the flow rate through the injectors, coupled with injection pressures of up to 2 500 bar, has improved the combustion process and lowered fuel consumption over a wide map range. The engine is also equipped with a variable turbine geometry (VTG) turbocharger proven for use in off-road applications.
As in the D3876 engine series, the D4276 features top-down cooling, with the coolant being pumped downwards from the top of the engine and distributed longitudinally through the upper cooling jacket of the cylinder head. The coolant flows on a cylinder-specific route along the injector jacket to provide special protection to points subject to high thermal stress in the cylinder head, such as injectors and valve seats. Modifications have been made to the crankcase and pistons to further improve the D4276’s cooling system.
The D4276 utilizes exhaust gas recirculation (AGR) with water cooling and the exhaust gas aftertreatment system consists of modules diesel oxidation catalytic converter and diesel particulate filter modules, coupled with a selective catalytic reduction system. The engine meets the most recent emission standards such as EU Stage 5 and US Tier 4. For countries with less stringent requirements, emissions downgrades to EU Stage 3a and 3b are available.