In the far extremities of a hydraulic system, the fluid can become stagnant and cold because of infrequent flow use by devices in that hydraulic branch. The cold fluid results in reduced performance for these devices when they are eventually called upon to perform.
An example of this would be the hydraulic actuators for the outer ailerons providing sluggish response to the pilots during high-altitude cruise. However, Parker’s heater valve helps maintain warm hydraulic fluid is available for all devices on the system, ensuring they can operate at peak performance at all times.
Parker Aerospace’s heater valve monitors the fluid temperature at the extremities of these hydraulic system branches. When the temperature drops below the ideal threshold, a small controlled stream of cold fluid is passed through a heating orifice and sent back through the system-return lines to the hydraulic reservoir. This allows warm fluid from the supply system to take its place. As soon as the proper temperature is achieved at these extremities, the heating-orifice flow through the return line is shut off to maximize system efficiency.
As a safety to the other devices in the system, a priority valve is integrated into the Parker heater valve. This ensures that even in a cold fluid situation where flow is being circulated back through the return line, the flow will be turned off if other higher-priority devices in the system require that hydraulic flow.
APPLICATIONS:
The Parker Aerospace heater valve is ideal for large hydraulic systems that have low standby hydraulic-flow devices in remote areas. For example, the Airbus A350 uses six devices per aircraft ensuring equipment in the wing tips and tail can perform at peak performance the moment they are required.
FEATURES AND ATTRIBUTES:
• Fully mechanical function, no electronics or power source required
• Heating circuit flow is turned off when ideal temperature is achieved to increase fuel efficiency
• Heater circuit flow is turned off instantly when higher priority devices require that flow for system safety
OPTIONAL FEATURES:
• Flow status sensor
• Temperature sensor