Hydraulic Filter Test Bench, rated to 150 LPM / 35 bar.

Introduction

The Neometrix Hydraulic Filter Test Bench is a high-precision ground support system designed to validate the performance, endurance, and safety of aircraft hydraulic filters before they are cleared for flight operations. Engineered in compliance with demanding aerospace and defence standards, it is tailored for organizations such as HAL, DRDO, DGQA, and international aerospace OEMs.

Modern aircraft — whether fighters, transport planes, or helicopters — depend on hydraulics as their muscle systems. Hydraulic circuits power landing gear, wing flaps, tail rudders, air brakes, steering systems, and, in the case of military platforms, even weapon release and retraction systems. Just as the human body requires clean blood to function, these systems require contamination-free hydraulic fluid to ensure uninterrupted performance.

At the heart of this reliability are hydraulic filters, which constantly clean the oil, trapping microscopic dirt, dust, and metallic particles. Without filters, contaminants could jam actuators, clog valves, or cause catastrophic system failures. The Neometrix Test Bench provides the ultimate quality assurance — verifying that every hydraulic filter meets strict aerospace safety criteria before entering service.

Why hydraulic filter testing matters

Hydraulic systems are unforgiving. A blocked filter or unnoticed contamination could mean:

• Landing gear refusing to deploy.
• Braking systems failing during landing roll.
• Wing surfaces jamming mid-flight.
• Weapon bay doors freezing during combat operations.

Such failures are not theoretical risks — they are mission-ending, potentially life-threatening scenarios. The Hydraulic Filter Test Bench exists to eliminate these risks by subjecting filters to real-world operating conditions. It ensures that:

• Filters maintain proper flow and cleanliness even at 150 LPM under 35 bar pressure.
• Differential Pressure Indicators (DPIs) and bypass valves trigger correctly when clogging occurs.
• Filters remain leak-proof and structurally sound under stress.
• Fluid delivered meets NAS 1638 Class 4 or better cleanliness standards, ensuring aviation-grade reliability.

In essence, this machine guarantees that filters will protect the aircraft as designed, not just in theory, but in proven practice.

Technical specifications

Working fluid & reservoir

• Fluid: Hydraulic oil conforming to MIL-H-5606G or equivalent.
• Tank capacity: >200 litres, constructed from SS304 stainless steel with 3 mm thickness.
• Design: Dished-end bottom for sediment drainage, contamination sampling port, breather cap, glass-type level indicator, and float switch for low-level alarms.
• Mounting: Rigid free-standing MS channel framework for long-term durability.

Pumps & flow control

• Pump types: Fixed delivery pump for steady flow, and a variable delivery automatic control pump to simulate dynamic operating conditions.
• Capacity: Up to 150 LPM flow at 35 bar.
• Pressure adjustment: 0.3–35 bar via adjustable relief valves.
• Operating temperature range: Designed for oil temperatures up to 60°C.
• Coupling & vibration isolation: Pumps coupled to high-quality motors with vibration dampening for smooth operation.

Cooling & heat management

• Heat exchanger: Plate-type, water-cooled, optimized for North Indian summer conditions.
• Temperature range: Maintains oil temperature at 25 ± 10°C, even during peak loads.
• Control: Remote ON/OFF valve for chilled water integrated into control panel.

Filtration banks

• Configuration: Multi-pass filtration system with separate banks for pressure and return lines.
• Performance: Capable of delivering fluid cleanliness up to NAS Class 4.
• Clogging detection: All filters equipped with electrical clogging indicators, displayed on the control panel.

Instrumentation

• Pressure measurement: Range 0–50 bar, accuracy ±0.25%, digital readout with least count of 0.01 bar.
• Flow measurement: Range 5–150 LPM, accuracy ±1%, digital display in LPM.
• Temperature measurement: Range 0–135°C, accuracy ±1%, digital indicators for tank, line, and post-heat-exchanger conditions.
• Fluid level: Sight glass indicator plus electronic low-level switch interlocked with the pump.

Safety & interlocks

• Automatic shutdown in case of low oil level, motor overload or overheating, excessive pressure build-up, filter clogging condition, or power supply phase disorder.
• Emergency stop switch for immediate system isolation.
• Transparent protective covers for safe observation of test filters.
• Noise reduction: System designed to operate below 90 dB at 1 m distance.
• Stainless steel piping & fittings to eliminate corrosion risks.

Control system

• Enclosed test panel with pressure, flow, and temperature displays; clogging indicators; ON/OFF switches and emergency shutdown.
• Manual valves for flow control, pressure regulation, and ON/OFF operation.
• Electrical wiring: IS-standard compliant, moisture/heat resistant, with coded routing and cable trays for neat installation.
• Calibration ready: Integrated ports for in-situ calibration of gauges, transducers, and flowmeters.

Applications

The Neometrix Hydraulic Filter Test Bench is used for:

• Acceptance testing — verifying new filters before release to service.
• Routine validation — checking in-service filters during scheduled maintenance.
• R&D and development — supporting new filter designs during prototype and certification stages.
• Aerospace quality control — enabling OEMs and MROs to maintain compliance with international standards.

It is ideal for air force bases, MROs, OEM production lines, aerospace R&D facilities, and defence laboratories.

Advantages of the Neometrix solution

• Defence-grade reliability: Engineered specifically for aerospace and defence applications.
• End-to-end capability: Covers design, manufacturing, installation, commissioning, training, and after-sales service.
• Compliance: Adheres to DGQA, CEMILAC, ISO 9001, and international aerospace norms.
• Trusted partner: Systems deployed across HAL, DRDO, BARC, and global research institutions.
• Operator-friendly: Clear control panels, digital readouts, and built-in safety interlocks make the system easy and safe to use.
• Durability: Stainless steel construction, vibration-isolated pumps, and robust design ensure long service life.

Conclusion

The Neometrix Hydraulic Filter Test Bench is more than a test system — it is a critical safeguard for flight safety. By simulating real operating conditions, it ensures that every hydraulic filter fitted to an aircraft is robust, leak-proof, and capable of maintaining the required cleanliness standards. Whether in defence or civil aviation, this system ensures that hydraulic filters — the unseen guardians of aircraft safety — are thoroughly proven before they protect pilots, passengers, and missions in the skies.