Hydraulic and Pneumatic Power Systems Flashcards
What are three types of hydraulic fluids?
Mineral, Polyalphaolefins, and Phosphate esters
What happens to plastic resins, vinyl compositions, lacquers and oil base paints if exposed to a phosphate ester based hydraulic fluid such as Skydrol?
The material will be damaged, softened, and or peeled
What color is mineral base hydraulic fluid?
Red
What feature is built into a hydraulic pump drive system to prevent engine damage in the event of pump seizure or overload?
A shear section in the pump drive shaft
What precautions should be taken to minimize contamination during replacement of a hydraulic unit?
All lines should be plugged or capped after disconnecting
What would cause a hydraulic filter to go into open bypass, allowing unfiltered fluid into the system?
A clogged filter
What are two types of engine driven hydraulic pumps?
Constant delivery and variable delivery
How does a gear type power pump operate?
Two meshed gears revolve in a housing and are driven by a power unit. Fluid is trapped and pressurized as the gears rotate
What is the purpose of a pressure relief valve?
To limit the amount of pressure, preventing failure of the system components
What is the purpose of a pressure regulator?
To manage the output of the pump to maintain system pressure and allow the pump to turn without resistance.
What is used in some hydraulic systems to supplement the power pump when several units are operated at the same time?
An accumulator
What are the different types of accumulators
Spherical and cylindrical
For what purposes are pneumatic systems used in some aircraft?
To operate brakes and doors,
drive pumps,
and engine starting
What are sources of pneumatic power?
Storage bottles, vane type pumps, and turbine engine compressors
What happens to excessive pressure in a pneumatic system?
A relief valve will bleed it into the atmosphere
