Protecting the “Heart” of the Fluid Power System

The most important area of filtration in any fluid power system is protecting the pump. After all, the pump is the “heart” of the system. Like the human body, we must protect our heart. If the heart breaks down or gives out, we die. Likewise, in any fluid power system, if the pump breaks down or gives out, the system either dies or a new pump must be installed or the current one repaired.

In some cases downtime is not an option and could cost upwards towards millions of dollars. We think about protecting other components in a system and even filtering the fluid before it goes back to the reservoir. But the suction line gets very little consideration.

Shouldn’t we place a filter in this line to protect the pump? Yes, we should. Whether you are protecting the pump in a $5,000 automobile engine, a $100,000 chemical processing system, or a $15 million power system, the pump must be protected.

Now here is a very important fact that we all learned in Filtration 101; The finer the filtration, the more efficient the filter. We all know that. Protecting the pump, however, generally does not require super sub-micronic filter. If filtration is too fine, it will starve the pump and cavitation will occur. This defeats the purpose of protecting the pump.

Generally speaking, pumps, whether it is a vane, gear, piston, variable displacement, or any other type of pump, they can take some beating, some more than others. There are guidelines as far as how fine the filtration should be in the suction line depending on which type of pump is being used.

So when making a determination of the level of filtration remember the following statement; It’s not how clean can you get the fluid, but how dirty can the fluid be to still get the job done effectively and efficiently.

Most pumps require a filtration level of 30 mesh (595 micron) to 200 mesh (74 micron). If you have any questions or issues, always ask a filter specialist or in some cases pump manufacturers who sometimes require a specific filtration level in order to uphold the warranty and keep it in effect. Requirements of your specific application may vary.

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