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Do You Know What The Primary Hydraulic Fluid Contaminants Are?

Making sure that your hydraulic system remains free and clear of contaminants is essential to ensuring the reliability and longevity of your system as a whole. Refuse or flotsam in your system can severely damage your hydraulic components, including valves and hydraulic motors, which can be extremely costly and time-consuming to replace.

For any plant or machinery that relies on hydraulics, developing a comprehensive contamination control strategy should be high on the priority list. Developing realistic and effective cleanliness targets for your system is the first step to ensuring that your system operates as intended.

The Primary Contaminants

The most common hydraulic fluid contaminants are particles and moisture. Depending on your industry and environment, there may well be other forms of contaminants, but these two forms are the most common and wide-reaching of all possible contaminants. A similar approach can be and should be used for other contaminants, which can include both heat and air. Remember, all contaminants, no matter how small, can have a degrading effect on your system, so keeping your hydraulic fluid clean should be your top priority.

Particle Contamination

Your primary concern should be silt-sized particles in the 1-10 micron range size. Whilst small in nature, even smaller than 1/10th of the thickness of a human hair, 3-micron sized particles are five to ten times more likely to cause a failure of some kind. To put that into perspective, your red blood cells are only 3-microns in size.

The main reason for this is, simply, that few filters are designed to remove such small particles. Another factor is that dynamic clearances in pumps and valves, which is the separation between moving parts under operating load, speed and temperature, are typically in the 1-5 micron size range. Particles are typically categorised into three ranges, >4 microns, >6 microns, >14 microns.

Water Contamination

Water is the second most common and insidious contaminant and it can really cause lasting damage to your hydraulic motors and components. Present in most hydraulicfluids, even in the most pristine environments, water can actually increase the failure rates 10-20 fold depending on the systems circumstances.

Water in hydraulic oil can cause a range of problems in your hydraulic system. Firstly, any iron or steel surface that happens to be in contact with water will inevitably start to rust. This can induce premature system failure as a result of corrosion, as well as introduce damaging rust particles to the fluid. Water is also very different from most hydraulic fluids changes in pressure and temperature can readily induce a phase change.

Under atmospheric pressure inside the reservoir, water will remain as a liquid; by the suction side of your hydraulic pumps can cause the water to vaporise, even at relatively low temperatures. These will form vapour-filled bubbles which will continue to grow until they reach an area of high-pressure, where the bubble will suddenly collapse.

This miniature implosion can cause devastating damage to your hydraulic system this is typically known as vaporous cavitation.

Industry-Leading Hydraulic Motors And Components, From Flowfit

Here at Flowfit, we are proud to offer resilient and reliable hydraulic motors and system components to ensure that your hydraulic system operates as required, preventing hydraulic fluid contaminants from affecting your system. From industry-leading hydraulic motors to a variety of valves and filters, youll be certain to find whatever you're looking for amongst our diverse range of products.

For more information, feel free to get in touch with the Flowfit team directly on 01584 876 033 or email us at and well get back to you as soon as we can!

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