Swivel Joint/Swing Joint Assembly E25 E26 E27 E32 E34 E35 E37 E38 E42 E45 E50/55/60 PN 7427431 Genuine Part

An excavator hydraulic swivel joint—also referred to as a swivel block, rotary manifold, or center swivel joint—is a specialized mechanical component that allows hydraulic fluid to transfer between fixed and rotating parts of the excavator (namely the undercarriage and the upper structure) while enabling the upper body to rotate freely, often a full 360°.

Key Functions & Benefits

• Continuous Hydraulic Flow: It enables uninterrupted flow of hydraulic fluid to essential components like the boom, arm, travel motors, and attachments—even while the machine rotates .

• Prevent Hose Tangling & Damage: Without a swivel joint, hydraulic hoses would twist or kink as the excavator rotates, leading to failure or costly repairs.

• Durability and Stability: Designed to tolerate heavy loads, high pressure, and constant motion, the swivel joint ensures long-term reliability and reduces wear on the hydraulic system.

• Precise Slewing Control: It not only enables rotation but supports accurate control of the excavator's turning speed and direction

How It Works

Internally, the swivel joint consists of:

• A center shaft with drilled channels for hydraulic fluid.

• An outer housing that encases the shaft and remains with the rotating upper structure.

• Seals and bearings that maintain hydraulic pressure and allow rotation without leaks.

When the excavator operates, hydraulic fluid travels through these internal channels, bypassing the need for flexible hoses to twist—maintaining smooth operation regardless of how many turns the upper structure completes.