MAN Engines have unveiling the MAN D4276, its new engine series for agricultural applications. With a 142 mm bore and 170 mm stroke. Generating an impressive 581 kW from 16.2 litres of displacement, the diesel engine is setting new standards.
Weighing no more than 1,280 kg, this power pack is not only the most powerful inline six-cylinder engine for agricultural machines that MAN Engines has ever developed, but also has the highest power-to-weight ratio in its displacement class. This peak output has been achieved by MAN Engines as a result of its newly developed charging concept with fixed geometry charger, which enables a maximum torque of 3,400 Nm between 1,350 min-1 and 1,600 min-1. “With the D4276, we are offering OEM manufacturers an engine that is easy to integrate and will help set them and their machines apart from the competition, thanks to its unique performance characteristics,” commented Reiner Rössner, Head of Sales at MAN Engines. To comply with current emission levels, the D4276 relies on the compact, flexible and modular exhaust gas aftertreatment (EGA) system from MAN Engines, and will be available for the main markets in models meeting the EU Stage V and EPA/CARB Tier 4 emission standards.
16.2-litre displacement for unparalleled power-to-weight ratio
The D4276 is based on the modern D3876 engine series, which is already successfully established on the market, but has been systematically developed to meet the increased performance demands of heavy applications in agricultural machinery. To achieve this, it was necessary to further improve the already outstanding power-to-weight ratio of the D3876. This meant expanding the bore by four millimetres from 138 mm to 142 mm, which had the effect of increasing the displacement from 15.3 to 16.2 litres. A modification of the Common Rail injection system provides the necessary increase in fuel supply. The use of a fully redeveloped high-pressure pump generates supply quantities up to 40 percent higher while vibration loads and noise emissions remain constant. Diesel injectors that have been further developed especially for the D4276 with improved flow and high injection pressures of up to 2,500 bar ensure an ideal degree of fuel atomisation and penetration. This results in low-emission, low-soot combustion combined with more favourable levels of fuel and AdBlue© fluid consumption.
Innovative charging concept for peak performance
To obtain maximum power of 581 kW, MAN Engines has developed a charging concept with a high power output in the upper engine speed ranges. Due to the required power characteristics, a fixed geometry charger is used in the process. As a result, the 6-cylinder engine offers a maximum torque of 3,400 Nm between 1,350 min-1 and 1,600 min-1 – which is sufficient power for large combine harvesters and forage harvesters, for example. During the thermodynamic design process, the engineers at MAN Engines came up with a turbine geometry that has its optimum efficiency level specifically in the main driving range of off-road machines. In addition to this, the turbine geometry was designed in such a way as to prevent the cylinders from interfering with each other during the charge cycle, thereby achieving good response characteristics and an optimal air throughput across all engine speed ranges. Turbine housing made from heat-resistant cast steel and compressor housing made from aluminium that can withstand high temperatures further increase the turbo charger’s robustness and create thermal reserves for use at high altitudes, for example.
