Hydraulic Test Equipment > Flushing & Pressure Test Rig > Fixed Flushing & Pressure Testing Rig


The hydraulic test rig has two purposes. These are to test the integrity
of the installed aircraft hydraulic systems in respect to pressure and 
leakage and to cleanse the internals of the system by flushing out any 
contaminants. In other words they are combined flushing and pressure 

aerospace test rigs.


The system is a semi static facility compromising two hydraulic test 
rig units statically plumbed into the production area. The test rig 
units can be decoupled from the plumbing and removed for major service 
or repair if necessary. Consequently they are built within frames that 
allow lifting, handling and safe transport. The hydraulic test rigs have 
suitable access points for maintenance.

The hydraulic test rig units have reservoirs to store the Skydrol™ hydraulic 
fluid and pumps to provide pressure.  The hydraulic test rig units also 
provide pressurised nitrogen into the system. The hydraulic test rig units 
have electric control systems for both the hydraulic rig itself and the test 

operations on the wing.

The rigs are designed to handle phosphate ester hydraulic fluids such asPressure___Flushing_Rig_web_
Hyjet and Skydrol to Airbus specification NSA307110. It is a requirement to
function test the system and check for cleanliness to a standard of NAS 1638
class 7 or better using a particle analyser.


The hydraulic test rig units are electrically controlled programmes via HMI 
with manual control. The input is by a touch screen on the front of the rig 
and via a remote HMI.

The hydraulic test rig units have a capacity of 400 litres of Skydrol™ LD-4 
hydraulic fluid held in reservoirs. The structure is of unpainted stainless 
steel with survivability and cleanliness in mind. A tray is located at the 

bottom of the rig capable of containing 100% of the Skydrol capacity.

The hydraulic test rig units have Skydrol™ resistant cable and cable conduit 
with the route of the cables and the looms designed to avoid contamination 
from hydraulic leaks. Also the design of rig and pipe runs route and collect 

any hydraulic leaks with minimal impact on rig, with suitable drain points.

The hydraulic test rig units were supplied fully assembled and tested, and 
complete with all general arrangement drawings, test certificates and manuals.

Suction System:
  • Nitrogen low-pressure test to 15 bar +0 bar, -1 bar Mechanisms_of_hydraulic_test_rig_web_
  • System flushing at a minimum flow rate of 100 LPM
  • Fluid pressure test at 15 bar +0 bar, -1 bar 
  • System evacuation:  purge system with nitrogen 

Main Systems:
  • Nitrogen low-pressure test to 15 bar +0 bar, -1 bar
  • System flushing at a minimum rate of 100 LPM
  • Fluid pressure test at 65-bar +/- 5 bar
  • Wing tooling valves closed.
  • Fluid pressure test at 150-bar +/- 10 bar 
  • Fluid pressure test at 350 bar +70 bar, -0 bar 
  • System evacuation:  purge system with nitrogen at approximately 0.7 to 4 bar.

The hydraulic test rigs incorporate the following primary functions:

  • Flushing: 122 LPM at a maximum pump pressure of 30 bar
  • Pressure testing:  9 LPM at a maximum pump pressure of 420 bar with a proportional 
  • relief valve via the PLC and HMI to control the pressure.
  • Nitrogen system purge and nitrogen pressure test.
  • Fluid testing: Utilising a Parker I count particle analyser.
  • Separate offline cooling / filtration system utilising an air blast heat exchanger
  • Separate reservoir filling pump system