Testing & Flushing
All FOX-VPS actuators are subjected to a stringent test regime prior to delivery. Utilising purpose built test rigs, actuators are initially pressure and leakage tested to a standard that exceeds ISO 10100:2001. They are then dynamically friction tested to verify that their ultra-low friction characteristics are uniform throughout the actuator stroke. The test comprises cycling the actuator from end to end at extremely low speed using a servo valve under position control, whilst simultaneously measuring the differential pressure across the piston. A plot is then generated of position vs pressure, an example of which is shown below.
FOX-VPS has installed an ultra clean hydraulic power unit that is used to cyclically flush actuators valves and manifolds. Actuators are automatically cycled end to end with their return oil continuously sampled for contaminants, with the process continuing until the oil reaches an ‘ISO’ cleanliness standard of 15.13.10 NAS Class 4 or better if specified. The rig is capable of cleaning to a standard of 9.8.7 NAS Class 0.