Hydraulic oil contamination: know how to control

As we discussed in another text, hydraulic oil systems are fundamental components of large machines and industrial equipment, which act in the lubrication and in the transmission of force for the movement of the internal parts. Therefore, the good state of conservation and the performance of all machinery depends directly on the good maintenance of hydraulic oil and its systems.

Contamination of hydraulic oil and its systems is a serious problem, which represents the main hydraulic failure in industries. Gradually evolving, this causes compromised equipment life, requires more frequent changes of parts and fluids, requires higher maintenance costs and even generates catastrophic failures. Find out how to protect your equipment and control hydraulic oil contamination. Let’s see below:

Most common hydraulic oil contaminants

The contamination of hydraulic oil consists of a slow and gradual process, often unnoticed, which causes more and more loss of efficiency and productivity over time. In contaminated hydraulic systems, for example, there can be a loss of efficiency of up to 20% before the problem is detected, which would represent one day of wasted productivity per week.

Small particles, 2 to 5 microns in size, are the most dangerous contaminating agents for today’s systems. Due to the size of the clearances in these systems, particles of such size can initiate premature wear and loss of efficiency, even in small quantities. There are several forms of contaminating agents. Some of the most frequent types are:

  • Dust
  • Air
  • Water
  • Sand
  • Ink
  • Grease
  • Heat
  • Cigarette ashes
  • Wear metal particles
  • Fabric fibers (usually detached from cleaning cloths)

Maximum permissible hydraulic oil contamination levels

In addition to promoting the removal of unwanted particles, water itself is a contaminant, which, like all others, must be eliminated. In situations of contamination of this nature, the water may be in a dissolved state or in a “free” (or emulsified) state, in which it is above the saturation point of a given fluid, that is, that fluid is no longer capable of dissolving or retain water. Typical saturation points are divided according to the type of fluid, according to the following information:

  • Hydraulic fluid – 300 ppm (parts per million) or 0.03% concentration
  • Lubricating fluid – 400 ppm or 0.04% concentration
  • Transformer fluid – 50 ppm or 0.005% concentration

Contaminating particles can penetrate a closed fluid system at various times, the main ones being:

  • When assembling the component / machine.
  • When storing or transporting new oil.
  • In maintenance, when the system is open for repairs or oil changes.
  • In the operation of the machine.

How to control hydraulic oil contamination

Current hydraulic systems have reduced cycle times and clearances between internal metal surfaces, while digging pressure, power and force are greater. All of these aspects made today’s equipment more productive and easier to operate; however, they are more subject to hydraulic oil contamination, requiring a greater need for cleaning fluid systems throughout the life of the machinery.

Check out some measures to control and prevent contamination of hydraulic oil:

  • Total cleaning of the system before starting the operation.
  • Filtering of all the fluid before placing it in the reservoir.
  • Application of plugs on hoses and manifolds during use and maintenance.
  • Proper storage of oil drums in dust-free and clean places.
  • Protection of oil drums with suitable lids after opening.
  • Conservation of replacement parts in their original packaging until the time of assembly.
  • Periodic analysis of the purity of the oil.
  • Conservation of the ideal temperature (replacement of worn fan belts, internal cleaning, etc.).

Filtering andmicrofiltration hydraulic oil are essential tools to prevent contamination of hydraulic oil and its systems. Such procedures consist of passing the oil through a set of filters that eliminate contaminating agents, ensuring cleanliness and good condition of the fluid.

These techniques extend the life of components, reduce downtime and increase the availability of hydraulic systems, maximizing their performance. Therefore, these methods are the right investment to reduce operating costs and avoid failures and corrective interventions in your business. Learn more about the importance of filtration for your equipment in our post.

Do you want more information about filtration, microfiltration and which one to use? Enter in contact with one of our experts or make aprice .

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