Hydraulic and lubricating oils are the lifeblood of every industrial machine. However, their chemical and physical properties are extremely sensitive to contamination. One of the most devastating contaminants is water. Even small amounts of free water in the oil can lead to acid formation and thus to corrosion of component surfaces. The solution is dewatering systems.

An increased water content in hydraulic systems dramatically changes the oil's characteristics. Load-bearing capacity is reduced, temperature resistance decreases, and viscosity is altered. In addition, humidity accelerates the depletion of additives and promotes the formation of foam and varnish. The consequences are far-reaching and include loss of performance, cavitation in pumps, uncontrolled valve movements, and accelerated oil aging due to oxidation.

These problems lead to reduced output, damage to components, and costly repairs. Possible causes of water ingress include radiator leaks, ambient humidity, splash water, and already contaminated fresh oil. To avoid economic damage, the oil must either be protected from water, or any existing water must be removed as quickly as possible. Effective oil dewatering can extend the service life of the entire machine up to four times.

In this article, learn about the dewatering systems ARGO-HYTOS offers for water separation in hydraulic systems and how you can significantly extend the service life of your hydraulic systems.

What dewatering systems are available for water separation, and why are they indispensable?

Various dewatering systems are available for removing water from hydraulic oil. Their application depends on the degree and type of contamination. Common methods include:

• Centrifugation
• Coalescence
• Absorption filtration
• Vacuum dehydration

Each method offers specific advantages and disadvantages in terms of efficiency, cost, and maintenance requirements.

Among the methods mentioned, vacuum dehydration in combination with specialized filter elements such as the EXAPOR^®AQUA series from ARGO-HYTOS is considered the most effective solution. This technological approach makes it possible to remove both free and dissolved water and keep the residual water content extremely low. This also significantly extends the service life of hydraulic oil.

The combination of these technologies achieves optimum fluid cleanliness, reduces component wear, and increases the overall reliability of hydraulic systems.

How do EXAPOR^®AQUA filter elements work to effectively separate water?

EXAPOR^®AQUA filter elements enable fast and efficient dewatering of hydraulic and lubricating oils by means of absorption filtration. This technology is particularly valuable in systems that use hygroscopic oils. It is also useful in environments with permanent water ingress, such as hydraulic and other mobile machines like, construction, reach stackers, forest machinery, municipal etc..

The special feature of EXAPOR^®AQUA is its dual performance. The elements consist of special water-absorbing filter layers and a micro-filter material. This effectively removes water from the oil while also ensuring the removal of solid contaminants. This allows the elements to be used even in hydraulic systems with the highest oil cleanliness requirements.

The filter elements can be used flexibly and offer the following advantages:

• Permanent protection: Built into ARGO-HYTOS offline filter units or filter systems, the elements can be permanently installed in the system to continuously remove water.
• Temporary dewatering: To remove residual water - for example, after refilling - EXAPOR^®AQUA elements can also be used in portable offline filter units during service.
• Integration: On request, suction or return filters can also be equipped with EXAPOR^®AQUA technology.

The efficiency of the dewatering process can be checked visually on site. As long as cloudiness is visible in the cooled oil, the water content is in most cases unacceptably high. If the oil sample appears clear, the water content is usually within the permissible range. However, an exact determination of the water content must always be carried out by Humidity sensors such as LubCos H20+ or oil analysis in laboratory.

The OPS2 vacuum drainage system: Comprehensive oil conditioning for demanding requirements

Vacuum dehydration is the most effective method for removing large quantities of water (whether free, emulsified, or dissolved). ARGO-HYTOS' mobile Oil Purification System uses this advanced technology for comprehensive conditioning of hydraulic and lubricating fluids.

The operating principle of vacuum drainage

The oil is heated to a defined temperature in the dewatering unit. It is then fed into a vacuum chamber. The negative pressure generated in the reactor causes the water to evaporate long before the normal saturation limit is reached. The resulting vapor is cooled, condensed, and collected in a collection tank. In this way, the OPS system not only removes water, but also degasses the hydraulic fluids.

Downstream, a built-in filtration module with fine filters ensures that solid contaminants are also removed. Powerful filter elements such as EXAPOR^®MAX or the conductive EXAPOR^®SPARK PROTECT elements can be used for this purpose.

The advantages of the OPS2 series

The OPS2 010 mobile dewatering unit offers a 20 percent increase in water removal speed. The dewatering rate for free water is typically around 1.2 liters per hour for 200 liters of oil with a water content of over 10,000 ppm.

Comprehensive process control with data management and operation

The mobile dewatering units of the OPS2 series offer complete control over the fluid conditioning process to ensure maximum reliability and transparency. The dewatering process is constantly monitored. Integrated sensors continuously measure important fluid parameters such as humidity, temperature, and conductivity during treatment.

This constant monitoring makes OPS2 a flexible device. The unit can either be controlled manually by the operator or operate in fully automatic modes with predefined settings and parameters. It is operated via an intuitively designed touch panel that clearly summarizes all settings and displays.

For data management, all measurement results are stored in the internal memory of the OPS2 system. The data can be printed out immediately during the cleaning process using the integrated printer, enabling quick documentation on site. Alternatively, the data can be copied to a USB stick at any time for further processing.

The XML format of the data allows for easy further processing in external devices. The results can also be assigned to individual profiles (e.g., specific customers or machines) to enable transparent management. These functions help to increase system availability and reduce operating costs.

The modular base system can be expanded with optional components as needed. These include a particle monitor for continuous cleanliness measurement or an additional heater to further increase dewatering efficiency.

ARGO-HYTOS: Your partner for fluid conditioning

The demands on the availability and service life of modern hydraulic systems are constantly increasing. Maintaining a high level of fluid cleanliness through reliable dewatering is an extremely important factor in this regard. Given the negative effects that water has on the chemical integrity and performance of hydraulic oil, consistent dewatering is essential.

Efficient oil conditioning can increase the service life of components up to fourfold, thereby drastically reducing operating costs and downtime. ARGO-HYTOS offers customized and integrated solutions with its EXAPOR^®AQUA absorptive filter elements and powerful OPS2 vacuum drainage systems. These solutions maximize the reliability, efficiency, and service life of your hydraulic systems.

Do you want to optimize your machine platforms, minimize risks, and increase operational safety? Then we are at your side as a partner for project development and application-specific engineering. Get in touch with our experts! They are available for personal consultation on ARGO-HYTOS solutions with no obligation.