Turbocharger and mating ring included therein

A mating ring for use in a rotating machine, the rotating machine including a shaft, and a carbon ring having a carbon surface having a carbon ring inner diameter and a carbon ring outer diameter spaced from the carbon ring inner diameter, said mating ring comprising:

• an interior surface extending along an axis between a first mating end and a second mating end spaced from said first mating end, with said interior surface defining a bore adapted to be disposed about the shaft;
• and
• a mating surface having a land portion adapted to contact the carbon surface between a first mating diameter adapted to be radially aligned with the carbon ring inner diameter with respect to said axis and a second mating diameter adapted to be radially aligned with the carbon ring outer diameter with respect to said axis, with said land portion having a land area between said first and second mating diameters;
• with said mating surface defining a plurality of grooved portions disposed about said axis, and with said plurality of grooved portions having a grooved area between said first and second mating diameters;
• wherein a ratio of said land area to said grooved area is between 1.3 and 2.9;
• wherein said plurality of grooved portions has a groove outer diameter;
• wherein a ratio of the carbon ring outer diameter to said groove outer diameter is adapted to be between 1.10 and 1.5;
• wherein said plurality of grooved portions has a groove inner diameter, and wherein a ratio of the carbon ring inner diameter to said groove inner diameter is adapted to be between 1.02 and 1.10;
• and
• wherein said plurality of grooved portions have a depth defined into said mating surface between 0.005 mm to 0.040 mm.

A turbocharger for delivering compressed air to an internal combustion engine and for receiving exhaust gas from the internal combustion engine, said turbocharger comprising:

• a shaft extending along an axis between a first end and a second end spaced from said first end along said axis;
• a compressor wheel coupled to said first end of said shaft;
• and
• a seal assembly comprising,
• a carbon ring disposed about said shaft and spaced from said compressor wheel along said axis, with said carbon ring having a carbon surface having a carbon ring inner diameter and a carbon ring outer diameter spaced from said carbon ring inner diameter radially away from said axis, and
• a mating ring disposed about said shaft and spaced from said compressor wheel along said axis such that said carbon ring is disposed between said compressor wheel and said mating ring, with said mating ring having a mating surface facing said carbon surface of said carbon ring,
• with said mating surface having a land portion configured to contact said carbon surface between a first mating diameter radially aligned with said carbon ring inner diameter with respect to said axis and a second mating diameter radially aligned with said carbon ring outer diameter with respect to said axis, and with said land portion having a land area between said first and second mating diameters, and
• with said mating surface defining a plurality of grooved portions disposed about said axis, and with said plurality of grooved portions having a grooved area between said first and second mating diameters;
• wherein a ratio of said land area to said grooved area is between 1.3 and 2.9;
• wherein said seal assembly further comprises a seal housing defining a seal housing interior;
• wherein said carbon ring is disposed in the seal housing interior;
• wherein said seal housing has an inner seal housing diameter with respect to said axis;
• wherein said carbon ring inner diameter is less than said inner seal housing diameter;
• and
• wherein said seal assembly further comprises a secondary seal coupled to said seal housing and said carbon ring, wherein said seal housing has a U-shaped portion with respect to and facing away from said axis, and wherein said secondary seal is disposed in said U-shaped portion.