The Ultimate Guide to Hydraulic Fluids & System Longevity

Hydraulic fluid is the backbone of industrial and mobile machinery, facilitating power transmission, lubrication, and cooling. Without it, hydraulic systems in mining, construction, and manufacturing would suffer from inefficiencies and premature wear. This article is designed for professionals responsible for maintaining and optimising hydraulic systems, including reliability engineers, maintenance managers, plant operators, and hydraulic technicians.

Whether focused on improving equipment uptime, reducing failures, or enhancing overall system efficiency, this guide provides valuable insights into hydraulic fluid selection, contamination prevention, filtration solutions, and best maintenance practices.

By integrating high-quality filtration solutions like Pall filters and leveraging Berendsen Fluid Power’s expertise, businesses can significantly extend hydraulic system life, improve efficiency, and minimise downtime. Investing in superior hydraulic maintenance today leads to long-term operational success.

4 Types of Hydraulic Fluids and Their Applications

Hydraulic fluids are formulated to meet specific operational needs. They have four primary types:

• Petroleum-based hydraulic oils: the most common type, known for excellent lubrication and thermal stability.
• Synthetic hydraulic fluids: Ideal for extreme temperatures and demanding environments.
• Water-based fluids: used in fire-resistant applications like mining and aviation.
• Biodegradable hydraulic fluids: environmentally friendly solutions for agriculture and marine industries.

  

Differences Between Hydraulic Fluid and Hydraulic Oil

Although the terms hydraulic fluid and hydraulic oil are often used interchangeably, there are key differences between them:

• Composition: Hydraulic oil is a type of hydraulic fluid made primarily from petroleum-based oils. Hydraulic fluid, on the other hand, is a broader term that includes synthetic, water-based, and biodegradable options.
• Applications: Hydraulic oil is typically used in industrial and mobile hydraulic systems, while hydraulic fluids are formulated for specific applications, including fire-resistant and environmentally friendly systems.
• Performance Additives: Hydraulic fluids may contain specialised additives for extreme temperature stability, anti-wear protection, and biodegradability, depending on the intended use.
• Environmental Considerations: Biodegradable hydraulic fluids are designed to reduce environmental impact, making them ideal for industries like agriculture and marine applications.

Choosing the right hydraulic fluid for your system depends on factors like operating conditions, viscosity requirements, and environmental impact.

Synthetic vs. Mineral Hydraulic Oils: Key Differences

Selecting between synthetic and mineral-based hydraulic fluids depends on several factors:

• Temperature resistance: Synthetic oils excel in extreme heat and cold.
• Oxidation stability: Synthetic fluids resist breakdown and last longer.
• Cost consideration: mineral oils are more budget-friendly but require frequent changes.
• Environmental impact: biodegradable synthetics reduce environmental risks.

How to Choose the Right Hydraulic Fluid for Your System

The right hydraulic fluid selection depends on:

• Viscosity requirements: ensuring the right flow characteristics.
• Additive compatibility: preventing corrosion, wear, and foaming.
• Temperature operating range: matching stability to system conditions.
• OEM recommendations: adhering to manufacturer specifications to prevent damage.

Common Contaminants in Hydraulic Fluids and How to Prevent Them

Contaminants are the leading cause of hydraulic system failures. The most common hydraulic fluid contaminations include:

• Particles (dirt, metal, rubber debris): entering through worn seals, hoses, and reservoirs.
• Water contamination: causing oxidation, rust, and premature fluid breakdown.
• Air bubbles (aeration & cavitation): leading to spongy controls and reduced efficiency.

Prevention Strategies:

• Utilise high-efficiency hydraulic filters.
• Store hydraulic fluid in sealed, moisture-free containers.
• Perform routine fluid analysis to detect contaminants early.

The Importance of Hydraulic Filters in System Longevity

Hydraulic filters are the first line of defense against contamination, playing a pivotal role in extending hydraulic system longevity. High-performance filtration eliminates harmful particles and moisture, preventing damage to pumps, valves, and actuators.

How Pall Filters Enhance Hydraulic & Filtration Systems

As a trusted name in hydraulic filtration, Pall filters are engineered to provide superior contaminant removal, maintaining optimal fluid cleanliness levels. The advanced technologies allow Pall Filters to enhance hydraulic & filtration systems by:

• Minimising downtime: reducing the risk of component failure and costly unplanned maintenance.
• Enhancing performance: ensuring smooth fluid flow and maximising efficiency.
• Extending equipment life: protecting critical hydraulic components from premature wear.

To further optimise hydraulic system performance, Berendsen’s Filtration & Lubrication Audit provides a detailed assessment of fluid cleanliness and filtration efficiency to further optimise hydraulic system performance. This industry-leading service helps businesses proactively address potential contamination risks, ensuring system longevity and reliability.

Effects of Temperature on Hydraulic Fluids and System Performance

Temperature fluctuations affect hydraulic fluid performance:

• Cold temperatures: Increase viscosity, causing sluggish operation.
• High temperatures: reduce viscosity, leading to poor lubrication and increased wear.
• Thermal breakdown: causes oxidation, sludge formation, and efficiency loss.

How to Mitigate Temperature-Related Issues:

• Choose fluids with appropriate viscosity index and thermal stability.
• Utilise cooling or heating systems to maintain optimal fluid temperature.

Environmental Considerations: Biodegradable Hydraulic Fluids

Industries are shifting towards biodegradable hydraulic fluids due to:

• Lower environmental impact: reducing soil and water contamination risks.
• Operator safety: less toxic compared to conventional oils.
• Regulatory compliance: meeting sustainability standards.

Hydraulic Fluid Viscosity: Why It Matters

Viscosity directly impacts hydraulic system efficiency:

• Flow efficiency: ensuring seamless fluid movement.
• Wear prevention: preventing excessive friction or poor lubrication.
• Energy efficiency: improper viscosity increases power consumption.
  
  

If you want to optimise your hydraulic system, you need to understand the importance of fluid viscosity. The right viscosity ensures smooth operation, reduces wear on components, and enhances overall system performance. Choosing the correct hydraulic fluid viscosity helps maintain efficiency, prevent overheating, and extend equipment lifespan.

The Role of Hydraulic Additives in Enhancing Performance

Hydraulic fluids contain additives to enhance longevity:

• Anti-wear agents: reduce metal-to-metal contact.
• Detergents & dispersants: keeping systems clean and sludge-free.
• Oxidation inhibitors: extending fluid life.
• Anti-foaming agents: preventing air entrapment.

How to Store and Handle Hydraulic Fluids

Best Practices:

• Store in sealed containers to prevent contamination.
• Avoid extreme temperatures to maintain stability.
• Clearly label fluids to avoid cross-contamination.
• Use clean tools to prevent dirt introduction.

Optimise Your Hydraulic System With Berendsen and Pall Filters

Keeping your hydraulic system clean is key to minimising downtime and maximising performance. Berensen Fluid Power’s expertise and Pall’s advanced filtration solutions provide reliable protection against contaminants, extended equipment life, and reduced maintenance costs.

Trust Berendsen Fluid Power to help you optimise your filtration system with industry-leading solutions. Contact us today to keep your operations running smooth!