In our previous newsletter, we explored the critical issue of particle contamination in oils. This time, we turn our focus to another significant threat to machinery health: water contamination. Water, an often-overlooked contaminant, can have a severe impact on both lubricating and hydraulic oils, compromising their performance and leading to accelerated machinery wear and failure.
Water contamination in oil can occur through various means such as condensation, leaks, or poor storage practices. For example, water can enter through seals in hydraulic systems, or via condensation in storage tanks during temperature fluctuations. Once water infiltrates the oil, it sets off a chain of degradation processes that severely affect the oil's properties and, consequently, the machinery it lubricates.
- Oxidation and Emulsification: Water promotes the oxidation of oil, leading to the formation of acids and sludge. It also causes emulsions, exacerbating wear and tear on machine components. This dual attack degrades the oil, reducing its effectiveness and increasing corrosion likelihood within the machinery.
- Lubricating Film Disruption and Viscosity Changes: Water contamination disrupts the oil's ability to form a stable lubricating film, compromising load-carrying ability. It also leads to changes in viscosity, causing the lubricant to thicken or thin. Viscosity is the most important physical property of a lubricant. Changes in viscosity directly affect equipment reliability, resulting in a loss of film strength necessary to keep surfaces apart.
- Hydrogen Embrittlement and Cavitation: Water can cause hydrogen embrittlement, where metal becomes brittle and prone to cracking under stress. It is also the leading cause of hydraulic pump cavitation. Water passing between frictional surfaces can explode, causing metal fracture and significant damage.
- Additive Depletion: Water contamination depletes essential additives in the oil. Additives, which have a natural attraction to polar materials like water and dirt, are consumed as they bond with these contaminants. This depletion reduces the oil's protective capabilities, leading to increased wear.
Industrial machinery operates in environments where water and humidity ingress is a constant risk. Early detection and continuous monitoring of water contamination are essential for maintaining machinery health.
- Real-Time Detection: Continuous monitoring allows for real-time detection of water ingress, enabling immediate corrective actions to prevent damage.
- Avoiding Transient Spikes: Spot checks and periodic analyses can miss transient or sudden spikes in water content, allowing contamination to reach damaging levels before detection. Continuous monitoring ensures that even minor contamination is identified and addressed promptly, preventing the escalation of wear and damage.
- Informed Maintenance: Regular condition monitoring enables more informed decision-making regarding maintenance schedules. By identifying contamination early, maintenance can be performed precisely when needed, avoiding unnecessary downtime and ensuring that machinery is always operating under optimal conditions.
Water contamination in lubricating and hydraulic oils is a critical issue that demands constant vigilance. Implementing a robust condition-monitoring program can help in early detection and mitigation of water contamination. By doing so, industries can ensure the longevity and reliability of their machinery, ultimately safeguarding production efficiency and reducing maintenance costs.
