What is a slewing bearing?

A slewing bearing or slewing ring (also called a turntable bearing) is a rotational rolling-element bearing that typically supports a heavy but slow-turning or slowly-oscillating loads in combination (axial, radial and moment loads), often a horizontal platform such as a conventional crane, a swing yarder.

How does an excavator swing bearing work?

In an excavator, a horizontally-mounted slewing ring bearing sits between the excavator's house and the excavator's undercarriage and its unique design allows for the excavator's house and attachments to swing infinitely in a circle through the aid of a swing drive attached to the house.

What is the purpose of the swing gear on an excavator?

A swing gear mechanism is operatively connected between the upper unit and the undercarriage to selectively rotate the upper unit. An operator-controlled locking mechanism is positioned interiorly of the swing gear mechanism to selectively lock the upper unit relative to the undercarriage.