A common issue with hydraulic systems, aeration is a potentially damaging phenomenon that results when there are excessive amounts of air in the fluid being used. Typically 10% of a normal hydraulic fluid will be dissolved air.  Aeration levels can exceed this in a number of ways: air leaks on the inlet side of the pump, inadequate pipe sizes, poor fittings and sudden changes in the cross sectional area of flow lines.  Sometimes, aeration can be traced to a reservoir whose fluid levels are too low, which creates a vortex that sucks air into the system. A leaky shaft seal may also create an entrance for air.

Why Aeration Causes Problems

The presence of excessive air in hydraulic fluid may not sound like a serious issue, but, in fact, it can cause a significant amount of damage if it is not corrected. Normally, hydraulic fluid performs the valuable function of lubricating system components, which keeps them from overheating. However, aeration compromises the lubricating ability of the fluid. Contaminated fluid also causes suboptimal system performance that can harm various components.

How to Detect Aeration

A hydraulic system suffering from aeration will emit a banging or knocking sound. This is due to air bubbles circulating through the system. Often, aerated fluid has a foamy appearance. Air being sucked into the intake lines may produce a whining noise.

What to Do

Make sure that all seals, hoses, fittings, and lines are connected properly and free of tiny holes or cracks that could allow air to enter. Remember that aeration frequently results from an issue with the inlet lines, so these should be given special attention.

How White House Products Can Help

Aeration is often caused by the use of old, defective equipment. We invite you to explore our online catalogue for high-quality, brand-new hydraulic pumps and related accessories from leading contemporary manufacturers.

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