Hydraulic oil dialysis: what it is and when to do it

Like diesel oil, hydraulic oil dialysis derives from the principle of filtering blood through the kidneys. In the case of hydraulic oil, cleaning is even more critical, since 70% to 80% of hydraulic system failures are caused by problems arising from contamination by particles or moisture in the oil.

Find out below what this cleaning process looks like and why it is so crucial for large machines.

What is hydraulic oil dialysis?

Before providing information about this type of filtering, it is important to understand the context from which it originates. Every hydraulic system requires the installation of filters along its critical points, which in general are the return lines and pressure lines. The most common are filters installed in the return line, particularly in the case of mobile machines, such as tractors and excavators. In addition to these locations, filters can be installed off-line, or off-line.

Due to the importance of cleaning the hydraulic fluid, it is common for combinations of filtration systems to be made on a case-by-case basis. The filters internal to the hydraulic circuit are capable of retaining large and medium particles, whereas fine and ultrafine particles are retained by external filtration systems, such as hydraulic oil dialysis machine.

These, in turn, can be called filters bypass (from Portuguese “bypass”), and receive this name for diverting the flow of oil from the hydraulic system and, consequently, from the internal filters to the interior of the dialysis machine. For this reason, a hydraulic oil dialysis system requires an exclusive pump.

Because it is not inserted into the hydraulic system, the dialysis equipment is not subjected to variations in pressure and oil flow inherent in the circuit. Therefore, it is capable of performing reliable microfiltration without adding pressure to the hydraulic assembly in operation.

So, the main advantage offiltration by hydraulic oil dialysis it is the retention of finer particles, however harmful, that are not captured by the filter system attached to the machine in its manufacture. This is because, thanks to the folding configuration of the filter element, this system has greater retention capacity and takes more time to clog than other simpler filters.

Why should I do this on my machines?

All hydraulic oil has a certain amount of contamination, even when new. Inherent degradation processes (oxidation, nitration, acidification), however, and contamination by moisture, particles and bacteria are inevitable and can reach levels that compromise the quality of the oil and expose the hydraulic system to failures, breakdowns or even total loss.

Most of these contaminations occur in the storage tank. Therefore, the hydraulic fluid must be constantly analyzed and, if necessary, subjected to cleaning using systems such as hydraulic oil dialysis.

It is estimated that approximately 70% to 80% of hydraulic failures occur due to negative consequences of oil contamination. In this sense, the quality of the filtration will have a decisive influence on the health of the machine.

Unlike the filtration system of the human body, dialysis in hydraulic oil needs specialized attention and care, since it does not happen automatically. In addition to the destructive effects on system components, contamination in hydraulic oil has several negative consequences, such as:

  • Loss of energy and lubrication capacity.
  • Loss of heat transfer capacity, causing components to overheat and hydraulic system failures.

Since hydraulic power is the primary force in large projects (timber harvesting, ore extraction and transportation, road construction, among others), stoppages of mobile and stationary equipment can result in significant losses in production, as well as unexpected expenses .

What are the benefits of periodic hydraulic oil dialysis?

The correct choice of the ideal filtration system for your hydraulic system results in the improvement of the production processes as a whole. Among the benefits that you will enjoy when performing hydraulic oil dialysis routinely, we highlight the following:

  • Reduced loss of productivity and production.
  • Decrease in maintenance costs.
  • Cost reduction with replacement or repair of parts.
  • Cost reduction with oil disposal and replacement.
  • Increased machine and oil life.

Systematic filtration is recommended, especially in the case of production systems that cannot stop due to the high fixed costs involved with out of operation machines, in addition to losses in production. Since large fleets of equipment of significant size use massive volumes of hydraulic oil, all possibilities of cost cuts and reduction of downtime for maintenance matter, which can directly impact the company’s competitiveness.

In the case of hydraulic systems, the quality of their cleaning is essential to guarantee the efficiency, effectiveness and reliability of the planning and execution of the projects. Thus, hydraulic oil dialysis is both essential and strategic for the success of the enterprise to which machinery using hydraulic force is associated. In this sense, cleaning the oil ensures that the engines operate in optimal conditions, minimizing engine and production losses, in addition to reducing the fleet’s ecological footprint.

Hydraulic oil dialysis is an investment

Finally, hydraulic oil dialysis is a filtration system that must be installed outside the circulation line inherent to the equipment. Due to this configuration, it is not subject to pressure and flow variations that occur with the operation of the circuit. The system off-line makes use of more advanced technological resources, and is therefore able to retain finer particles of contaminants that the internal filtration system was unable to do so.

Hydraulic oil dialysis is an investment that allows a significant reduction in costs for maintenance, replacement and disposal of these fluids, since it extends the useful life of both the oil and the machine. For this reason, the installation of a dialysis system is critical in hydraulic systems, which are even more sensitive to contamination by water and particles.

Make one nowpricefrom POC Filters and learn how hydraulic oil dialysis can cut your maintenance costs, in addition to reducing your company’s environmental impact.

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