Rotary Union Testing for Extreme Environments

United Equipment Accessories (UEA) has completed extensive client specific testing over the years. Our hydraulic swivel line is no exception. Not only do we offer endurance and application testing for our hydraulic rotary union customers as part of our development and design process, but we also test and pressure check every unit before it leaves UEA.  This allows us to provide our customers with peace of mind when they receive their products.

Endurance and application testing have been vital in assisting our customers in the forestry industry.  Forestry equipment has to withstand extreme environments, including high vibrations, freeze and thaw, high heat, long run times, varying RPMs, and both high and low pressures.  All these things must be taken into consideration when designing rotary unions.  With all this in mind, we generate customer-specific protocols to ensure we are testing the full needs of the customer. Below are just a few examples of protocols we have developed for our customers to design and validate their rotary unions.

Example Rotary Union Testing Protocols:

Multiple Rotation Testing

  • Tested the hydraulic swivel at different rotations and pressures with continuous monitoring and recording of the pressure, torque, leakage, and seal durability
  • Successfully completed 32,000 cycles (approx. 500 hours) with no leakage, torque, or pressure issues
  • One complete cycle – 2 different types of rotations at 1.5 times the max pressure on all ports, testing torque and for leaks

Robust Forestry Application Testing

  • 16,000 cycles total
  • 10×90° oscillations then one full rotation to equal one cycle
  • Low, medium, and high pressures were cycled through the hydraulic swivel
  • Heated anti-freeze was pushed through coolant side
  • Heated anti-freeze was allowed to cool then heated

Results from Tests

  • Deadhead pressure check at the end of the test showed seals had no leaks
  • Seals showed very slight wear with plenty of life left
  • The spool and housing hardware had no noticeable wear
  • Torque remained constant throughout the test

In the forestry industry, extreme vibration is a challenge for designing rotary unions.  This can cause havoc for off-the-shelf products. Our forestry designs went through their vigorous testing to make sure our rotary unions can handle these extreme scenarios.

When working in extreme environments or challenging applications, UEA stands out with our engineering team and testing equipment to provide rotary unions to our customers that need their application requirements.