Hydraulic systems are present in numerous industrial sectors, including automation, metal processing, energy, Oil & Gas, earthmoving, and much more. However, these systems are extremely sensitive to the quality of the oil used, and its contamination by solid particles or water is one of the main causes of degradation, leading to sudden failures, reduced efficiency, and high maintenance costs.
According to industry studies, over 75% of failures in hydraulic circuits are attributable to oil contamination, a figure that highlights how crucial continuous monitoring of fluid quality is to prevent malfunctions and ensure maximum operational efficiency.
The main sources of hydraulic fluid contamination
The hydraulic fluid, which not only transmits energy but also performs functions of lubrication, cooling, and protection of metal surfaces, can be subject to various forms of contamination during system operation:
- initial contamination: this refers to processing or assembly residues that remain inside the system from the production or maintenance phase. These include dust, paints, metal chips, and traces of other materials that can cause immediate or progressive damage to hydraulic components;
- system-generated contamination: during normal use, the components of the hydraulic system undergo wear and tear, generating metal particles and other residues. Additionally, phenomena such as oil oxidation and additive degradation can contribute to the formation of invisible but dangerous contaminants;
- ingested contamination: the system can absorb impurities from the surrounding environment, especially if there are openings that are not properly sealed. Dust, humidity, and processing residues can enter the circuit through vents, defective gaskets, or during oil refilling.
The consequences of contamination
The presence of contaminants in hydraulic oil can cause numerous problems that compromise the efficiency and lifespan of the entire system:
- accelerated wear of critical components: solid particles in the oil can act as an abrasive, rapidly deteriorating pumps, valves, and actuators, and reducing their service life;
- blockage of conduits and valves: accumulations of particles or sludge can narrow or obstruct crucial passages, reducing fluid flow and causing malfunctions;
- increased internal friction: contaminated oil loses its lubricating properties, leading to an increase in friction between moving surfaces and, consequently, an increase in operating temperatures;
- higher energy consumption: an inefficient hydraulic system requires more energy to function correctly, leading to an increase in operating costs;
- sudden failures and costly machine downtime: contamination can cause the sudden collapse of key components, halting production and generating significant economic losses.
Contamination monitoring: particle counters and humidity sensors
To ensure that the oil maintains its optimal properties, it is essential to constantly monitor the level of contamination using predictive maintenance tools such as particle counters and humidity sensors.
Particle counters: how they work and why they are essential
Particle counters are devices capable of analyzing in real-time the quantity and size of solid particles present in the oil, classifying them according to international standards such as ISO 4406, NAS 1638, and SAE AS4059.
These tools are essential because they allow to:
- early identify the presence of contaminants, signaling any deviation from the reference parameters and allowing targeted interventions before the problem becomes critical;
- perform a historical analysis of the oil, comparing the data collected over time to identify degradation trends and prevent anomalies before they can compromise the system's operability;
- reduce maintenance costs, avoiding unnecessary interventions and limiting the premature replacement of still-functioning components.
An example of advanced technology is the LPA3, a portable particle counter that offers immediate oil analysis and can be used directly in the field for a rapid assessment.
The importance of monitoring water in oil
In addition to solid contamination, water represents a significant threat to hydraulic systems, as even in small quantities it can lead to serious consequences:
- corrosion of metal components: water accelerates the oxidation and deterioration of exposed metal surfaces, reducing the lifespan of components;
- decrease in lubricating properties: the presence of water modifies the oil's viscosity and reduces its effectiveness as a lubricant, increasing friction and wear;
- oil oxidation and precipitation of additives: when oil comes into contact with water, some essential additives can degrade rapidly, compromising the fluid's performance;
- valve blockage and emulsion formation: the mixing of water and oil can lead to the formation of emulsions that are difficult to remove, affecting the correct functioning of the system.
Filtrazione e tecnologie di rimozione dell’acqua
To keep the hydraulic oil in the best condition, in addition to diagnostics, it is necessary to intervene with appropriate filtration solutions. Among the most effective solutions are:
- filters with water-absorbing elements, which capture and retain moisture before it can cause damagei;
- mobile filtration units, ideal for oil purification without having to interrupt plant operation.;
- water-oil separation systems, which remove free water, preventing emulsion and corrosion problems.
The strategic value of advanced oil monitoring
Investing in contamination monitoring tools and predictive maintenance technologies is a strategic choice for any company that uses hydraulic systems. Particle counters, humidity sensors, and advanced filters are indispensable allies to improve productivity, reduce costs, and ensure more reliable and sustainable plants in the long term.