A cleaning device for cleaning and/or polishing a surface having an aperture, such as a wheel rim contact surface of a motor vehicle or the like, comprises a housing, which has a rear rotary portion for rotating the housing about a rotational axis and a front fastening portion for releasably fastening a cleaning body; the cleaning body comprising a stabilising plate which faces the housing and has a centring pin that faces away from the housing and projects centrically towards the outside, and a cleaning means that covers the surface of the stabilising plate that faces away from the housing; and the fastening portion and the stabilising plate each having a corresponding connecting means for rotationally stable connection to one another.

Method of reducing the thickness of a bore of a cylindrical workpiece for use as a gear. The method involves the steps of: mounting a cylindrical workpiece having a horizontal central axis and an outer diameter in a grinding machine; and grinding the bore of the cylindrical workpiece to reduce its thickness using a grinding wheel that has a diameter that is from 40% to 80% of the outer diameter of the cylindrical bore and has a direction of rotation about an axis of rotation that is parallel to the horizontal central axis of the cylindrical workpiece. The axis of rotation of the grinding wheel may be located from 90 degrees to 180 degrees, in the direction of rotation of the grinding wheel, from a plane that extends vertically through the workpiece when it is mounted in the grinding machine. The gear may be one of a planetary, sun, parallel axis or helical gear.

Method of reducing the thickness of a bore of a cylindrical workpiece for use as a gear. The method involves the steps of: mounting a cylindrical workpiece having a horizontal central axis and an outer diameter in a grinding machine; and grinding the bore of the cylindrical workpiece to reduce its thickness using a grinding wheel that has a diameter that is from 40% to 80% of the outer diameter of the cylindrical bore and has a direction of rotation about an axis of rotation that is parallel to the horizontal central axis of the cylindrical workpiece. The axis of rotation of the grinding wheel may be located from 90 degrees to 180 degrees, in the direction of rotation of the grinding wheel, from a plane that extends vertically through the workpiece when it is mounted in the grinding machine. The gear may be one of a planetary, sun, parallel axis or helical gear.

A wheel weight-reducing pit cleaning device comprises the lower lifting driving system, the side brush system, the ring brush unit, the ring brush system, the clamping driving system, the pressing system, The present disclosure in use is capable of cleaning and removing the burrs on the edges of the drain groove and the weight loss groove at the wheel weight-reducing pit.

A process for manufacturing a hollow roller of a roller bearing including steps of: machining an outer radial cylindrical surface, with a circular cross section centered on a first axis, and machining an inner radial cylindrical surface with a circular cross section centered on a second axis. These two steps are realized on the same lathe. The hollow roller is provided with the outer radial cylindrical surface, with a diameter of at least 5 mm, and the inner radial cylindrical surface. An offset between the first axis and the second axis, measured in the hollow roller between two axial surfaces of the hollow roller, is less than 2 m, and an inclination angle between the first axis and the second axis is less than one minute of angle. The roller bearing comprises amongst others, at least one such hollow roller.

A process for manufacturing a hollow roller of a roller bearing including steps of: machining an outer radial cylindrical surface, with a circular cross section centered on a first axis, and machining an inner radial cylindrical surface with a circular cross section centered on a second axis. These two steps are realized on the same lathe. The hollow roller is provided with the outer radial cylindrical surface, with a diameter of at least 5 mm, and the inner radial cylindrical surface. An offset between the first axis and the second axis, measured in the hollow roller between two axial surfaces of the hollow roller, is less than 2 m, and an inclination angle between the first axis and the second axis is less than one minute of angle. The roller bearing comprises amongst others, at least one such hollow roller.

A liner system for installation in a rotatable mill shell having an inner side and an opposed outer side, the liner system including one or more lifter bars. The lifter bar includes a body, a channel plate secured to the body and defining a channel axis, including one or more lateral extensions extending transversely from the central portion in relation to the channel axis, and one or more insert elements positioned between the lateral extension and the inner side of the mill shell, for resisting outward movement of the lateral extension toward the inner side. The liner system also includes one or more attachment assemblies, each including a bolt, for securing the lifter bar to the mill shell. The insert elements are configured to maintain the bolt in a predetermined position in which an axis of the bolt is aligned with the channel axis.

A liner system for installation in a rotatable mill shell having an inner side and an opposed outer side, the liner system including one or more lifter bars. The lifter bar includes a body, a channel plate secured to the body and defining a channel axis, including one or more lateral extensions extending transversely from the central portion in relation to the channel axis, and one or more insert elements positioned between the lateral extension and the inner side of the mill shell, for resisting outward movement of the lateral extension toward the inner side. The liner system also includes one or more attachment assemblies, each including a bolt, for securing the lifter bar to the mill shell. The insert elements are configured to maintain the bolt in a predetermined position in which an axis of the bolt is aligned with the channel axis.

A grinding arm for grinding workpieces with an inner profile with a grinding wheel. The grinding arm has a tube-shaped base body with a longitudinal axis, in which the grinding wheel is supported at one axial end region. A first drive for the grinding wheel is arranged in its other axial end region. A first transmission system transmits the rotation from the first drive to the grinding wheel. In order to adjust arbitrary angles of inclination of the grinding wheel in the grinding arm, the grinding wheel is arranged on a grinding spindle driven by the first transmission system and rotating around an axis of rotation. The grinding spindle is supported in a carrier body arranged in the base body rotatable around an axis perpendicular to the longitudinal axis as well as perpendicular to the axis of rotation, wherein the axis of rotation and the axis intersect.

A grinding arm for grinding workpieces with an inner profile with a grinding wheel. The grinding arm has a tube-shaped base body with a longitudinal axis, in which the grinding wheel is supported at one axial end region. A first drive for the grinding wheel is arranged in its other axial end region. A first transmission system transmits the rotation from the first drive to the grinding wheel. In order to adjust arbitrary angles of inclination of the grinding wheel in the grinding arm, the grinding wheel is arranged on a grinding spindle driven by the first transmission system and rotating around an axis of rotation. The grinding spindle is supported in a carrier body arranged in the base body rotatable around an axis perpendicular to the longitudinal axis as well as perpendicular to the axis of rotation, wherein the axis of rotation and the axis intersect.