Microscopic ferrous particles are the most dangerous contaminants in any fluid system.
Very careful thought has to be given to the filtration of fine ferrous particles from your system, because the manufacturer may not have done so. Barrier filtration and compliance to ISO cleanliness standards offer only limited protection against this risk.
Ferrous contaminants are typically the hardest, sharpest and smallest contaminant threat in a system. It causes leakages and dimensional changes, it reduces system efficiency and, because of its tendency to lodge in dynamic clearances and agglomerate, it will create a chain reaction of wear leading to sudden and catastrophic system failure.
This is especially true of closed loop systems, such as, hydraulics, engines, pumps and transmissions etc (lubrication and fluid power systems), where small amounts of contaminant work as destructive elements within the system for long periods of time.
However ferrous particles are also a high risk factor in open systems such as industrial processing, machine tooling, product washing etc, where huge amounts of debris need to be removed from the fluids each day, before they can cause significant damage to the final product, and also be transferred to other processes.
This ‘high-risk’ contamination cannot be seen by the naked eye, and ISO cleanliness standards do not address all of the size ranges of contamination that threatens systems.
Traditional barrier filtration is also not, on its own, sufficient to protect your system.
Removal of fine ferrous debris down to sub-micron levels is essential if you want to enhance system lifetime and reduce system downtime, especially when solenoid valves, close tolerance VP pumps and immersed circuitry are used, and when typical system dynamic clearances are getting even smaller the threat increases significantly.
The picture speaks for itself: Here we see a bearing from a typical pump, after the pump had failed catastrophically because of erosive wear from ferrous contaminants.
Where does the contamination come from?
Inbuilt – Most systems suffer from contamination left from manufacture, machining, threading, cutting etc its just not been possible to prevent this… Until Now!
Break In – As components engage with each other for the first time in a new system this sees high levels of Ferrous material produced and distributed throughout the new machine.
Generated – Contaminants are generated by wear as the machine/system operates, and clearly the more inbuilt and ingressed contamination there is, the more wear contamination will be created
Ingressed – External particles can find their way into any system. This can be from poorly sealed units or even rust ingress, but even brand new oil is more than likely to introduce some contamination.