BorgWarner turbochargers are being deployed on the Mercedes-Benz medium-duty, commercial vehicle diesel engines—the 5.1-liter, four-cylinder OM 934 and the 7.7-liter, six-cylinder OM 936—to help the OEM meet Euro VI compliance. Both engines are fitted with the B-series turbocharger as standard; a high-performance variant for the engines use the companies regulated two-stage (R2S) turbocharger, which combines a small high-pressure and a larger low-pressure turbos. The B-series turbos feature titanium compressor wheels, and electric actuators for the wastegate and turbine bypass control. To improve thermodynamics, packaging, and installation, parts of the exhaust manifold are integrated into the turbine housing.
“Compared with current standards, Euro VI emissions standards challenge engine manufacturers to reduce nitrogen oxides by about 80%,” said Pete Kohler, president and general manager, BorgWarner Turbo Systems Commercial Diesel Products. The company’s B-series turbos are being used on the new OM 934 and OM 936 Mercedes medium-duty diesel engines to help meet the emissions requirements.