Abstract: The invention relates to a method for determining bearing play of exhaust-gas-turbocharger friction bearings comprising the following method steps: accelerating the exhaust-gas turbocharger or the body group from standstill to a maximum rotational speed and at the same time registering the vibration acceleration by means of a sensor; determining the constant-tone frequency of the friction bearing at at least one rotational speed; plotting the determined constant-tone frequency in a diagram, in which bearing-play ranges determined experimentally in advance are assigned to constant-tone frequency ranges; and establishing whether or not the determined constant-tone frequency lies in a bearing-play target range.

Abstract: In the generic exhaust-gas turbocharger, the turbine-side and compressor-side radial bearing bush are of identical design. A more compact bearing space, and improvements in acoustics and rotor dynamics, are achieved by providing different bearings on the turbine and compressor sides.

Abstract: The present invention relates to an exhaust-gas turbocharger (1) having a compressor (2); having a turbine (3); having a bearing housing (4) which is connected at one end to the compressor (2) and at the other, turbine-side end (5) to the turbine (3) and which has an oil collecting chamber (6) at the turbine-side end (5) and which has a plain bearing arrangement (7) for a rotor shaft (8), which plain bearing arrangement comprises a compressor-side bearing (9?) with an inner bearing surface and an outer circumferential surface, and comprises a turbine-side bearing (10?) which is spaced apart axially from the compressor-side bearing (9?) and which has an inner bearing surface (11) and an outer circumferential surface (12), wherein the compressor-side bearing (9?) and the turbine-side bearing (10?) are of different design.

Abstract: The invention relates to a method for determining bearing play of exhaust-gas-turbocharger friction bearings comprising the following method steps: accelerating the exhaust-gas turbocharger or the body group from standstill to a maximum rotational speed and at the same time registering the vibration acceleration by means of a sensor; determining the constant-tone frequency of the friction bearing at at least one rotational speed; plotting the determined constant-tone frequency in a diagram, in which bearing-play ranges determined experimentally in advance are assigned to constant-tone frequency ranges; and establishing whether or not the determined constant-tone frequency lies in a bearing-play target range.