What is a Hydraulic Filter? How to Choose a Hydraulic Filter | Hidroman
What is a Hydraulic Filter? How to Choose a Hydraulic Filter | Hidroman
What is a Hydraulic Filter and How to Choose It? — Technical Guide in Hidroman Expertise
Hydraulic Filter: The Unsung Hero of Your System
Hydraulic filters are the most critical line of defense for your hydraulic system. By keeping dirt, water and particles in the hydraulic fluid; It protects pumps, valves, cylinders and sensitive components. Without these filters, 70–85% of system failures are due to oil contamination — which means serious performance losses, costly downtime and component damage.Hidroman Hydraulics
Choosing the right filter doesn't just provide "clean oil"; It also increases system efficiency, extends maintenance intervals and minimizes unexpected downtime.
Why is Hydraulic Filtration So Important?
The main functions of hydraulic fluid:
Energy Transfer
Heat Transfer
Lubrication of moving parts
Ensuring sealing
If any of these tasks are adversely affected, system life and performance will drop dramatically. Fluid contamination can interrupt all of these tasks.Hidroman Hydraulics
Clean oil > Stable power transmissionLow contamination > Reduced wear Proper filtration > Increased system life
Types of Hydraulic Filters: The Right Choice for Your Application
Every application is different; Therefore, the type of filter must be chosen correctly:
- Suction Line Filters
It removes impurities before pumping. It prevents large particles from passing into the system. It usually has a high micron value (e.g. 100 μm).Hidroman Hydraulics
Where is it used?
Pump protection
Dirt removal during the assembly phase
- Pressure Line Filters
They operate under high pressure in the system. It is critical for protecting sensitive valves and components.Hidroman Hydraulics
Highlights:
High strength (100–420 bar)
Low pressure loss
- Return Line Filters
The oil in the system is cleaned as it returns. This ensures that the oil is constantly replenished.Hidroman Hydraulics
Advantage:
Increases filtration time
Extends system life
- Off-Line Filters
It works independently of the main circuit. It provides clean filtration with high precision and can control oil temperature.Hidroman Hydraulics
Field of use:
Critical high-volume systems
Lines that require ongoing maintenance
Technical Selection Criteria: ISO, β Value, Pressure Loss
Choosing the right filter is not just about determining the type. The following criteria are essential for high-performance systems:
ISO 4406 Cleaning Standard
The dirt level of the fluid is measured according to the ISO 4406 standard. This standard; classifies according to particle size and number.Hidroman Hydraulics
Example: ISO 18/16/13 level is ideal for industrial systems.
Filter Element Performance: β Value
β value indicates how efficiently a filter retains particles of a specific micron size. High β value = higher filtration efficiency.Hidroman Hydraulics
β10 = 500 → 99.8% of particles over 10 μm are retained (technical example).
Pressure Loss and Bypass
No matter how effective filtration is, pressure loss affects system performance. ΔP (pressure difference) is an important criterion in filter selection. Additionally, a bypass valve should be considered to maintain oil circulation in the event of a blockage.Hidroman Hydraulics
Application Example: If the flow rate is 50 L/min, the bypass opening pressure can be targeted at 3.6 bar.
Filter Element Material and Design
The filter element directly impacts system efficiency. Common Materials:
Wire mesh / metal – Surface filtration
Fiberglass / cellulose – Deep filtrationHidroman Hydraulics
Deep filtration retains smaller particles, keeping the system cleaner in the long run.
Filtration + Oil Analysis = Maximum Reliability
Filtration alone is not enough. In hydraulic systems, the examination of oil through microscopic analysis provides real-time assessment of system health.Hidroman Hydraulics
Laser parts counter measurements clearly show system performance.
Conclusion: Right Filter, Right Performance
The choice of hydraulic filters should not be solely cost-oriented. The optimal filter type, material, β value, pressure tolerance, and ISO target should be determined based on system needs. Proper filtration ensures that the most expensive components are protected in Hydraulic circuits.
At Hidroman, we offer hydraulic filtration solutions with our principles of high precision, longevity, and system reliability — tailored for each system. It makes a difference, especially in mass production, industrial line and OEM applications.