Slewing bearing

A slewing bearing or slew[ing] ring is a rotational rolling-element bearing or plain bearing that typically supports a heavy but slow-turning or slow-oscillating load, often a horizontal platform such as a conventional crane, a swing yarder, or the wind-facing platform of a horizontal-axis windmill. (To "slew" means to turn without change of place.)

Compared to other rolling-element bearings, slewing bearings are thin in section and are often made in diameters of a metre or more; the slewing bearings on the Falkirk Wheel are 4 metres diameter and fit over a 3.5 metre axle. Slewing bearings resemble oversize aircraft control surface bearings.

Slewing bearings often use two rows of rolling elements. They often use three race elements, such as an inner ring and two outer ring "halves" that clamp together axially.

Slewing bearings are often made with gear teeth integral with the inner or outer race, used to drive the platform relative to the base.

As for other bearings that reciprocate, rather than rotating continuously, lubrication can be difficult. The oil wedge built up in a continuously rotating bearing is disrupted by the stop start motion of slewing. Instead, a hydrostatic bearing with pumped oil flow may be used.

The three row roller slewing bearing has three seat rings,which separate the upper,lower and radial raceways,

it made each row of the roller's load capacity can be specified and can bear different loads simultaneously.

The capacity load is the largest one compare with the other three models.Due to the large size in axial and

radial dimension the solid structure, it is specially suitable for the heavy  duty machinery such as wheeled

excavator,wheeled crane, ship crane,ladle turrets and the heavy duty mobile crane etc.

Note:

1. n1 is the numbers of lubricating holes. Oil cup M10×1JB/T7940.1~JB/T7940.

2. The Oil nipple's location can be change according to the user's application.

3. n-φ can change to tapped hole, the diameter of tapped hole is M, and depth is 2M.

4. The tangential tooth force in the form is the max tooth force; the nominal tangential tooth force is 1/2 of the max one.

5. "K" is addendum reduction coefficient.