Why Are Bypass Necessary in Filtration?

Why Are Bypasses Necessary in Filtration?

When an element is installed in a hydraulic system the media become blocked over time due to the removing of particulates from the medium that is being filtered. Eventually this can lead to an increase in the pressure drop across the filter and if the media becomes too blocked can lead to an increase in the pressure of the hydraulic system.

Once this pressure increase becomes of a sufficient level the bypass within either the housing or element will trigger allowing the medium to bypass the element and relieve this build-up of pressure within the system.

In the event that the bypass does not trigger or there is no bypass installed and the pressure becomes sufficiently high, one of two things can happen:

  1. The element will collapse.
Example of a Collapsed Filter

2. A back-pressure will build up which could potentially cause catastrophic failure to the hydraulic system.

This can be prevented by installing an indicator on the filter housing which will show when the filter has bypassed or when the pressure has reached a pre-determined pressure which is set to be before the filter has collapsed. Once the indicator has activated the element should be replaced to stop the filter bypassing, and therefore allowing particulates to go unfiltered which could cause damage to your machine.

Filter Indicator