Hydraulic Systems Flashcards
What does a single-acting actuator do?
Uses hydraulic pressure to move the piston in one direction
What does a double-acting actuator do?
Allows the piston to move in two directions
What do selector valves do?
- Operated by the pilot
- It directs fluid pressure to various parts of the system
What are the two types of pumps?
- Constant pressure pump
- Spur gear
Ways in which a pump can be driven are…
- Electrically
- Ram Air Turbine (RAT)
- Engine
- Hand
Functions of the reservoir
- Store XS fluid
- Allows thermal expansion
- Stack pipe to provide an emergency supply
What do accumulators do?
Store pressure energy using compressed nitrogen
Why do filters have a by-pass?
In case of a blockage
Relief valves
Vent excess pressure
Restrictor valves
Reduce flow speed
Priority valves
Maintain pressure in one part of the system
Shuttle valves
Supply a service from the highest power source
Fuse valve
To shut off a leaking part of the system
What is a PTU used for?
One hydraulic system can power the other as they are duplicated
What can indicate a leak in the system?
High temp or low pressure
What can high system demand cause?
Temporary low pressure which leads to slower activation of services
Minimum hydraulic system requirement for commercial jets
Duplicated system
