The Dirty Truth About Hydraulic Oil Filtration

An estimated 70% of component replacement is due to surface degradation or wear. In hydraulic and lubrication systems, half of those replacements are down to mechanical wear, and a fifth to corrosion. Yet both those problems can be picked up by oil analysis – often well before the problem turns into a crisis.

So your assets not only avoid being dismantled for “investigative surgery”, but can be “treated” without the need for a major operation.

Getting down and dirty

There are essentially four types of oil contamination (see below), and each one can cause different problems within the system. The only thing they have in common is that each one is bad news.

But simply identifying their presence is not enough. The results of the oil sample need expert interpretation to pinpoint the root cause of the contamination, so you can take steps to resolve it.

That’s why ERIKS’ independent laboratory oil analysis service goes beyond simple sampling and reporting. It also includes comprehensive and expert analysis by a qualified Application Engineer.

If your power packs become very hot, water in the oil could be condensation. Or there may be a leak into the hydraulics from the cooling side of the system.

ERIKS’ experts will know what to look for, where to look, and can either guide your engineers or inspect the system for you, before addressing the root causes of the problem.

Code breakers

If you adhere to the ISO Cleanliness Code, you may be thinking that dirty oil isn’t something you have to worry about. Unfortunately, that’s not the case.

Every hydraulic component has an ISO code to guide you on the level of filtration required. But cracking the code and choosing the correct filtration depends on a number of variants, including the system operating pressure and the particular components within the system. In fact there could be a number of different codes and a number of conflicting filtration levels indicated for one system, leaving you none the wiser about which to choose.

ERIKS’ expert Application engineers are able to advise you on the correct code to observe and the right filtration rating to adopt, to ensure the optimum service life for all components within your hydraulic system.

So after hydraulic oil analysis by ERIKS, you can expect:

• Confirmation of the ISO Cleanliness Code you should be following, and of the filtration micron rating you need to be operating
• Interpretation of the contaminants present in the oil
• Solutions (ranging from preventive maintenance to component repair or replacement) to the problems identified

If it’s possible to squeeze out that much essential information from a few drops of oil, surely it’s time to learn the truth about your own hydraulic system? Especially when the process is as simple as taking a sample.

Contaminants and their consequences

The 4 basic types of oil contaminants are:

• Solids – leading to abrasive wear, leakage, components failure etc.
• Liquids – a source of corrosion wear, sludge formation, cavitation etc.
• Gel-like residues – resulting in bearing wear, valve malfunction, dynamic seal damage etc.
• Gases – causing cavitation, oxidation, premature oil ageing etc.