Servo‑hydraulic actuators, proven to 80 kg/cm².

Why CCU testing matters

The Combined Control Unit (CCU) Test Rig is an advanced, industrial-grade platform designed for servo hydraulic actuator testing. Developed to meet the stringent needs of the aviation, aerospace, and defense industries, it ensures comprehensive performance verification of components used in helicopters and fighter aircraft.

The rig conducts various essential tests, such as frequency response analysis, dynamic load simulation, and cyclic tests, all automated with an integrated data acquisition system (DAS). This hydraulic testing rig is an invaluable tool for ensuring the safety and performance of flight control systems and other aviation-grade components.

1. Hydraulic system

The hydraulic system features a main and duplicate circuit with separate hydraulic power packs to reduce noise and vibration. The system is equipped with quick disconnect couplings (QCDC), oil sampling ports, and filter banks. It also includes automatic pressure control valves and digital pressure transducers for precise fluid regulation. The hydraulic power pack is located separately to minimize disturbances.

Working fluid is hydraulic oil AMR-10-GOST.6754-53, with a maximum pressure capability of 80 kg/cm². In functional mode, operating pressure ranges between 42 and 73 kg/cm², and the system can handle fluid temperatures up to 80°C. Cooling uses chilled water, while heating is achieved automatically through the hydraulic pump's relief flow. Hydraulic contamination is maintained to NAS 1638 standards.

2. Mechanical system

The test bench is designed with robust loading springs that generate adjustable test loads according to requirements — up to 1850 kg (K = 45, 62.5 kg/mm) at Pmax, or 1500 kg (K = 27, 42 kg/mm) for running-in tests. Test components are mounted on the test table using mechanical fixtures. The system incorporates load cells and linear variable differential transformers (LVDT) to measure load and displacement accurately.

3. Electronics, instrumentation & control

The instrumentation system automates the control and monitoring of critical parameters, including pressure, temperature, and leakage rates. It uses digital flow indicators, temperature sensors, and pressure transducers integrated with the data acquisition system (DAS) for real-time data logging and display. Leakage is measured over a 0–2000 cc range, with a nitrogen accumulator held at 30 ± 2 kg/cm². A 10 kW, 3-phase electric motor at 1460 RPM drives the hydraulic system, and stainless steel (SS 316) tubing ensures corrosion resistance and durability.

4. Software and automation

The control software is developed on LabVIEW 8.1 and features a graphical interface for intuitive operation. It supports connectivity with multiple hardware protocols such as GPIB, PXI, RS-232, and RS-485. Operators execute tests through a 17-inch TFT touch-screen, which provides access to test parameters, test sequences, and result visualization. The software offers both manual and fully automatic modes, with extensive password protection for different levels of access.

5. Operational modes

System Maintenance Mode — operators perform sensor calibration, system diagnostics, and fault isolation, with both automatic troubleshooting and manual diagnostics available through dedicated software tools.

Test Part (UUT) Mode — the primary testing mode, where dynamic testing of Units Under Test (UUT) takes place. The system runs pre-configured test sequences and provides real-time feedback on performance parameters. Operators select and execute tests via the touch-screen interface, with results displayed on dual colour monitors for easy reference.

Applications

This test rig is used for:

• Testing and adjusting Combined Control Units (CCU) in MI-8 helicopters and other aircraft.
• Acceptance, control, and periodic testing of servo units such as KAY-30B and PA-60B, per the specific test schedules of the components.
• Validating hydraulic actuators and servo control systems for aviation and defence.
• Simulating dynamic load conditions and performing critical performance assessments of hydraulic system components.

The system is tailored for aviation manufacturers, military maintenance facilities, and aerospace component engineers who require precise, reliable test results.

Technical specifications

Why choose the Neometrix CCU test rig

Our CCU Test Rig is built for organizations that demand precision, reliability, and automation in aerospace component testing. Designed to handle high-pressure hydraulic systems, complex servo control testing, and dynamic performance simulations, it ensures that your components meet the highest standards of safety and functionality.

The system is ideal for companies involved in aviation manufacturing, military equipment testing, defense contractor support, and hydraulic system engineering. It offers unparalleled flexibility with both automated and manual test configurations, making it a versatile tool for various testing scenarios.