- Hello Customer - Log in or Register!
Schaeffler has started volume production of its INA lightweight balancer shaft for the Mercedes-Benz OM 651 high-performance diesel engine, leading to a significant reduction in fuel consumption.
The OM 651 is a 2.2-litre, four-cylinder engine that produces up to 204ps and 500Nm torque.
The weight of the INA balancer shaft and bearing assembly is optimised to improve engine efficiency and reduce overall fuel consumption.
The INA lightweight balancer shaft was developed primarily for four-cylinder applications such as the OM 651 engine.
By replacing conventional plain bearings on the balancer shaft with rolling bearings, friction is reduced.
Using needle roller bearings with a raceway directly on the shaft reduces friction by up to 50 per cent over the whole speed range.
The width of the bearing has been reduced, which means that the weight of the shaft in the OM 651 could be cut by more than a third.
This equates to a weight saving of 0.75kg for the engine.
The lower mass moment of inertia reduces the load in the power train, therefore improving the acoustic characteristics.
In addition, the narrower raceway improves the oil mist supply to the rolling bearings, enabling a simpler system design without oil feed holes, reducing manufacturing costs.
The engine requires a lower throughput of oil, so the oil pump can also be made smaller.
These technical improvements meant that fuel savings of around 0.5 to 1 per cent were achieved.
The OM 651 engine will play a significant role in Mercedes-Benz's hybrid-engine vehicle fleet.
The engine can be combined with the modular hybrid systems for rear-wheel drive platforms.
The INA lightweight balancer shaft assembly can considerably reduce engine fuel consumption and emissions.
For example, based on an average reduction in fuel consumption of 1 per cent over the life of an engine, and calculated for a vehicle mileage of 250,000km, it would lead to approximately 175 litres of fuel savings.
Even if only 25 per cent of all four-cylinder engines were fitted with INA lightweight balancer shaft assemblies, this would still reduce harmful CO2 emissions by around 6 million tonnes per year.
| Product Model | Inside Diameter | Outside Diameter | Thickness |
| 7205DB KOYO | 25 | 52 | 30 |
| 7005CDB KOYO | 25 | 47 | 24 |