Existing form and working principle of excavator slewing bearing

The excavator slewing bearing is an indispensable structural component for mechanical rotation operations, and what form does the slewing bearing exist in this system structure? How does it work?

1. Slewing bearing

The excavator adopts a rotating column type slewing bearing. The rotation angle of the slewing part is generally equal to or less than 180°. It consists of upper and lower support shafts and upper and lower bearing seats welded on the slewing body. The bearing should be fixed on the frame with bolts, and the rotating body is rotated by the hydraulic motor inserted on the support shaft.

2. Turntable structure

The main bearing part of the turntable is a box-shaped structure welded by steel plates with high torsional and bending rigidity. The main frame, the boom and its hydraulic cylinder are supported on the lugs of the main beam.

When the hydraulic excavator is working, the position of the resultant force of the dead weight and the load on the upper part of the turntable is often changed, and is biased towards the direction of the load. In order to balance the load moment, each device on the turntable needs to be reasonably arranged, and a counterweight should be set at the tail to improve the force of the lower structure of the turntable, reduce the wear of the slewing bearing, and ensure the stability of the whole machine.

3. Transmission working principle

When the excavator is working, the position of the resultant force of the dead weight and the load on the upper part of the turntable is often changed, and is biased towards the direction of the load. In order to balance the load moment, each device on the turntable needs to be reasonably arranged, and a counterweight should be set at the tail to improve the force of the lower structure of the turntable, reduce the wear of the slewing bearing, and ensure the stability of the whole machine.

As the rotational speed increases, the flow required by the swing motor also increases. When all the oil of the hydraulic pump is supplied to the swing motor, the first stage of start-up ends. The accumulator releases its energy at this moment, so the hydraulic pump and the oil in the accumulator supply the rotary motor together, which speeds up the rotation speed of the rotary motor. This is the second stage of startup.