What Is The Central Rotary Joint Of Excavator

What is the Central Rotary Joint of Excavator?

Both of the upper and lower parts of construction machinery (such as excavator, crane, etc.) have hydraulic system and share a set of hydraulic system. The upper and lower parts have relatively large rotation Angle or continuous rotation, to prevent the hydraulic hoses from twisting. The central rotary joint not only enable the reversely continuous rotation of the upper and lower parts, but also makes the pipeline neatly placed, which is widely used in the construction machinery system.

Working principle

The central rotary joint is mainly composed of a shell, a spindle, a gland, a rotary seal and a standard part, etc. The internal structure is shown below.

The working process of the central rotary joint

The central rotary joint is generally connected with a flange on the shell, which is fixed to the center of the rotary bearing. The shell is connected onto the upper pipe, and the mandrel is connected onto the lower pipe.

During working, the body and core shaft rotate in opposite direction. Because of the design of circular oil passage in the body, it is able to rotate at any angle and maintain the connection between the oil passages of body and core shaft to achieve continuous rotation.