A bearing assembly includes a stationary component, a rotatable component and a preloadable double row bearing unit having a rotatable bearing ring and a stationary bearing ring and two rows of rolling elements between the rings. The rotatable bearing ring and/or the stationary bearing ring includes a first part and a second part, and the first part is spaced from the second part by a gap so that the first part and the second part do not touch. At least one elastic element is disposed in the gap and fills the gap.

A rolling bearing includes an outer ring as a fixed ring, an inner ring as a rotary ring, and rolling elements disposed between the outer ring and the inner ring. The outer ring includes, on the radially opposite side of its raceway surface, a fitting surface fitted to a mating member, two annular grooves in which elastic members are fitted, and a recess adjacent to the annular grooves, and the recess has a bottom surface having an outer diameter smaller than the outer diameter of the fitting surface.

A rolling bearing includes an outer ring as a fixed ring, an inner ring as a rotary ring, and rolling elements disposed between the outer ring and the inner ring. The outer ring includes, on the radially opposite side of its raceway surface, a fitting surface fitted to a mating member, two annular grooves in which elastic members are fitted, and a recess adjacent to the annular grooves, and the recess has a bottom surface having an outer diameter smaller than the outer diameter of the fitting surface.

A sleeve of a steering column includes (i) an outer tube and an inner tube that are movable relative to each other, and (ii) an adjustment system. The adjustment system includes a screw for adjusting the axial position along an adjustment axis constrained to move in translation with a first of the two elements by at least two guide bearings for rotationally guiding the adjusting screw about the adjustment axis. At least one of the bearings supporting the adjusting screw is a guide bearing with axial force take-up for blocking the translational movement of the adjusting screw.

A sleeve of a steering column includes (i) an outer tube and an inner tube that are movable relative to each other, and (ii) an adjustment system. The adjustment system includes a screw for adjusting the axial position along an adjustment axis constrained to move in translation with a first of the two elements by at least two guide bearings for rotationally guiding the adjusting screw about the adjustment axis. At least one of the bearings supporting the adjusting screw is a guide bearing with axial force take-up for blocking the translational movement of the adjusting screw.

A ball-hinged transmission shaft with a straight shaft includes a socket, a ball, and a straight shaft. A rolling element is further coaxially provided on a straight shaft. The rolling element is a rotator with an axis of the straight shaft as a center of rotation. An upper portion of the rolling element is connected to a bearing. A mouth-shaped surface is further respectively provided at two ends of a transmission hole of a ball. The mouth-shaped surface is a curved surface matching the shape of the rolling element. The rolling element is fit and provided in the mouth-shaped surface at the two ends of the transmission hole of the ball. The ball is restricted by an inner positioning spherical surface of a socket, the straight shaft, and the rolling element at the same time.

An improved serviceability gearing element generally includes a support having a plurality of obstacles for co-operating with teeth of a neighboring gearing element. The gearing element further includes a pin, a roller mounted to move in rotation about the pin via a rotary guide, blocking bearings shaped substantially to prevent the roller from moving in translation along the pin, and one or more fasteners for fastening at least one of the blocking bearings to the support.

An improved serviceability gearing element generally includes a support having a plurality of obstacles for co-operating with teeth of a neighboring gearing element. The gearing element further includes a pin, a roller mounted to move in rotation about the pin via a rotary guide, blocking bearings shaped substantially to prevent the roller from moving in translation along the pin, and one or more fasteners for fastening at least one of the blocking bearings to the support.

A tapered roller bearing includes an inner ring having a tapered raceway surface and a large-collar surface on a large-diameter side of the raceway surface, and tapered rollers. Each of the rollers has a large end surface guided by the large-collar surface. When R represents a set curvature radius of the large end surface and R.sub.BASE represents a base curvature radius from a vertex of a cone angle of each of the tapered rollers to the large-collar surface, the base curvature radius R.sub.BASE is 100 mm or less, and a ratio R/R.sub.BASE of the set curvature radius R to the base curvature radius R.sub.BASE is set to 0.90 or less. When R.sub.ACTUAL represents an actual curvature radius of the large end surface of each of the tapered rollers, a ratio R.sub.ACTUAL/R of the actual curvature radius R.sub.ACTUAL to the set curvature radius R exceeds 0.5.

A method of performing an operation such as a maintenance operation on a vessel assembly, said vessel assembly having a vessel, such as a crystallizing vessel, a rotor, said rotor including an upright, rotatable shaft, said shaft having a top shaft section extending above a top wall of the vessel, to perform maintenance. The top shaft section includes a first member chosen from a male member and a female member for engaging a device. The device has a top end, and a bottom end. The bottom end includes a complementary second member for the first member. According to the method, the device is connected to the top shaft section of the shaft, the rotor is lifted by lifting the shaft at its top end section using the device, following which the operation is performed.