Working principle of hydraulic center rotary joint

The structural characteristics and working principle of the central rotary joint. The central rotary joint is mainly used for pipeline connection in hydraulic and pneumatic machinery with rotary motion, such as excavators, cranes, aerial work vehicles and other engineering machinery. It is used to connect hydraulic and pneumatic pipelines of relatively fixed and rotating components, avoiding the entanglement of pipelines during rotational motion when using hoses for connection. The central rotary joint is mainly composed of a housing, a core shaft, a cover, a rotating seal, and standard components.

The central rotary joint generally has a flange on the shell, which is fixed to the center of the rotary support. The shell is connected to the upper pipeline, and the core shaft is connected to the lower pipeline. When the rotary support rotates, the shell and the internal core shaft produce relative motion. Due to the design of the annular oil passage of the shell, it can be turned freely within the circumference range, and the shell oil passage can be kept connected with the corresponding core shaft oil passage, achieving continuous rotation. During the use of the rotary joint, leakage caused by damage to the sealing ring cannot be avoided, and a new sealing ring should be replaced in a timely manner; Before replacing the sealing ring, it is best to check the true cause of the damage. If it is caused by particles sticking to the surface, it is necessary to clean and replace the damaged sealing ring in a timely manner; Before installing a new sealing ring, it is also necessary to do a good job of inspection. The burrs, particles, and other debris on the surface that may scratch the sealing surface of the sealing ring should be removed. Apply butter to the sliding surface and sealing ring, and then install it. Open circular grooves on the core shaft that are equal to the number of pipelines. Hydraulic oil from the inlet of the housing is supplied to the walking motor through the vertical holes on the core shaft through these oil grooves Even if the shell continuously rotates with the upper body, the grooves on the core shaft remain unobstructed with the oil ports on the shell, allowing hydraulic oil to freely enter and exit.