How Important Is Oil Cleanliness For Your Equipment?

MH Hydraulics FZC, a leading hydraulics solutions provider in the Middle East talks about the importance of cleanliness of hydraulic oil with the recommendation from their partner DES-CASE RMF Systems from USA and the Netherlands. In industries where high value and production focused equipment operate, it’s all about maximizing uptime, productivity & efficiencies. Oil is still too often seen as a consumable and doesn’t receive the attention it deserves & requires as it is one of the most important components of an industrial system. Without a lubricant your gearbox would get damaged within no time and without oil a hydraulic system doesn’t even work.

Contaminants such as particles and water can and will have negative consequences on the functionality of your systems. At first, you’ll see the performance and productivity decline and efficiencies of your machines and assets decrease, and thereafter unexpected component breakdowns will occur.

Approximately 70% of the machine failures are caused by surface degradation, also known as mechanical and corrosive wear. It’s known that mechanical wear such as abrasion, erosion, and fatigue causes a decrease in production, machine efficiency, and eventually component breakdowns and costly downtimes.

Also, water shouldn’t be underestimated as it is a serious contamination type that leads to issues like fluid oxidation, internal surfaces corrosion, additive depletion, and many more fluid failures. These failure modes will cause acceleration of the degradation process of the oil. These contaminants can also cause secondary contamination such as acids. sludge, varnish by products.

Contamination: where does it come from?
– New systems/components are usually contaminated from manufacturing processes.
– New oil is dirty oil, in almost all cases above the target cleanliness levels required for the
– Contamination ingress through (damaged) seals
– Contamination (particles & moist) ingress through filling cap/port / breather
– Internally generated contamination – friction / wear / abrasion / erosion / oxidation

To be able to measure the particle contamination level in a fluid there are two most used norms in the
industry, the ISO 4406 and the NAS 1636.

Developed by the International Organization for Standardization, the ISO Range Code is the commonly
used cleanliness code. The ISO 4406 code records the cleanliness level of a liquid by three numbers.
These numbers correspond with the number of particles respectively larger than 4, 6, and 14 microns
per 1ml or 100ml.

What you want to achieve is that the oil and your system stays in optimal conditions as long as possible
as this will directly result in:
 extended machine reliability,
 less breakdowns,
 less oil changes,
 longer remaining life of components & oil.

-> Ultimately resulting in a Higher Return on investment
Although inline full-flow filters are an essential part of a system, most of the time they are not capable to keep the oil at or below the target cleanliness & moisture levels.
The solution here is to adopt additional microfiltration to achieve these targets as these units
continuously improve the oil quality by reducing contamination levels.

Implement a contamination control strategy:
1. Set target -> Every component has a manufacturer specified ISO cleanliness and recommended
target moisture levels
2. Take action -> install desiccant breathers that will absorb particles and moist, install adequate
additional filtration.
3. Measure – Take samples on a regular basis to measure/evaluate the effectiveness of your actions.

There are two ways to implement the contamination control strategy using additional filtration: mobile and dedicated.

Mobile offline filtration:

Component required cleanliness by
manufacturer Typical clearance of different components
Mobile offline filtration:
Also known as periodic filtration, is a good start to
remove/degrease the contamination levels in the oil in
a system.

It’s an economical way to filter multiple assets with the
same filtration unit, especially when you want to filter
but have budget restrictions. It’s an Ideal choice/solution
for pre-filtering new oils as they arrive at your plant or
facility. Often used for periodic filtration of less critical
assets or where contamination build-up is less

Dedicated filtration:

Dedicated filtration is especially used in critical applications where downtime and the high associated
costs have a significate impact on the productivity and performance of the machines.
Keeping the contamination levels as low as possible is essential for the proper functionality of the system


Machines/systems require certain cleanliness levels to operate properly. Micron size particles and very small amounts of water cause most of the failures in assets like hydraulic systems, gearboxes, reducers and pumps. Therefore, it’s of utmost importance to keep the contaminants out of the lubricants as much as possible. Implementing the right contamination control strategy will result in:
 Increase of overall equipment RELIABILITY,
 Reduction of downtime & maintenance costs, (thus saving MONEY),
DECREASE our clients’ FOOTPRINT on the environment