Hydraulic Rotary Union

Discover the Ultimate Hydraulic Rotary Union for Seamless Fluid Transfer

A Hydraulic Rotary Union (often referred to as a Rotating Joint or Swivel Joint) is an indispensable component in modern industrial machinery, designed to transfer hydraulic oil, air, coolant, or other media from a stationary source to a rotating part, such as a roller, drum, or spindle. Our selection of Fluid Rotary Unions (FRU) is engineered for exceptional durability and leak-free performance under the most demanding conditions, ensuring your machinery operates at peak efficiency.

Working Principle

A hydraulic union operates by allowing pressurized fluid to pass through a stationary housing into a rotating shaft without leakage.
Inside, seals and bearings maintain isolation between circuits, even at high pressures and rotational speeds.

This ensures reliable hydraulic power transmission in equipment where both rotation and pressure coexist.

Types of Hydraulic Rotary Unions

1. Single-Passage Hydraulic Rotary Union

  • Designed for systems requiring one fluid channel.

  • Common in hydraulic cylinders and machine spindles.

  • Compact and simple structure, easy to maintain.

2. Dual-Passage Hydraulic Rotary Union

  • Supports both supply and return lines through one unit.

  • Ideal for hydraulic motors and rotary actuators.

3. Multi-Passage 

  • Handles up to 12 or more independent channels.

  • Allows simultaneous flow of hydraulic oil, coolant, and air.

  • Common in index tables, rotary manipulators, and robotic systems.

4. High-Pressure 

  • Built for extreme conditions (up to 40 MPa).

  • Used in injection molding machines, hydraulic presses, and excavators.

5. Stainless Steel Hydraulic Rotary Union

  • Resistant to corrosion and oxidation.

  • Suitable for marine, food-grade, or chemical processing applications.

Why Choose it?

  • Leak-Free Operation: Prevents fluid loss and system contamination.

  • Compact & Efficient: Saves space while maintaining performance.

  • Reduced Maintenance: Advanced seal materials increase lifespan.

  • Customizable Design: Configurable passages, ports, and materials.

  • Reliable Under Pressure: Designed for dynamic hydraulic conditions.

Conclusion

A Hydraulic Union is an essential component in any system that combines fluid pressure and rotational motion. Its robust design, high-pressure resistance, and multiple passage options make it indispensable for hydraulic machinery and automation systems.

Choosing the right model ensures leak-free performance, extended service life, and optimal power transmission efficiency—helping your equipment run reliably under the toughest industrial conditions.