205 AND 211 TRACK-TYPE EXCAVATORS Hydraulic Swivel (5-way and 2-way) Caterpillar

Hydraulic Swivel (5-way and 2-way)

Hydraulic Swivel (5-way and 2-way) - Fig. WH 227

The hydraulic energies between the rotating upper carriage and the stationary under carriage are transmitted through the hydraulic swivel.

5-way hydraulic rotating joint.

(0) Leak oil.(1) Hydraulic motor for right track, forward.(2) Hydraulic motor for right track, reverse.(3) Hydraulic motor for left track, reverse.(4) Hydraulic motor for left track, forward.

Connection 1 of accessory swivel joint = track brake.

Connection 2 of accessory swivel joint = q/min - q/max adjustment, track motor.

Six independent oil circuits are channeled from the upper to the lower carriage. Stator is fixed to the lower chassis in the center of rotation of the upper carriage. The hydraulic lines link the stator connections to the actuators listed above. The rotor A is mounted on the stator and is rotated by a carrier on the upper chassis. The pressurized oil flows from the pilot units, through the rotor connections, to the corresponding annularducts sealed off against each other. Through the individual multi-level bores in the stator, oil flows to the vertical oil ducts and through transverse bores to the connections provided in the lower part of the stator.

NOTE: The incidental leak oil lubricates simultaneously. For this reason the leak oil channel should always be filled after assembly. Bleed all other lines.

Connections 1 and 2 of the accessory swivel are subjected to hydraulic pressure.

Rotor A pivoted in the housing (stator) is maintained in axial direction by cap B. Connection screw C is held in place by tab washer D. Special sealing elements seal off the circular chambers. Each chamber is connected to an axial hole E and a radial threaded connection F and also through intermediate pieces G and H to a threaded connection I in connecting piece K.

Prior to fitting the rotating joint attachment onto the 5-way hydraulic rotating joint, connecting piece K must first be removed by unturning the loosening screw L. Then, the rotating joint with the lower part of the rotor (intermediary piece G/H) is fitted through the hole in the center of the 5-way swivel joint and fastened to the cover by screws. Finally, the connecting piece K with seal rings is screwed back to the intermediate piece H from below.

Not Shown:

The housing M is made to rotate with the upper carriage by means of carrier pins. In order to avoid distortion of the swivel joint connections, particular care should be taken during assembly that there is sufficient clearance between the bore in the housing flange and the carrier pin of the upper structure. For the same reason, the lines should be connected to the casing with hose connectors.


Grease O-rings and O-ring grooves with Molykote BR 2 Universal Heavy Duty Grease. (See the Operation and Maintenance Guide).