Hydraulic Principles Flashcards
How is pressure generated in a hydraulic system?
Resistance to flow.
True or false: oil is incompressible?
True.
A passive hydraulic system is a system that requires human power to raise blank.
A system that requires human power to raise tempurature.
How many pumps does an active hydraulic system have?
One or more.
What type of centred system uses pressure only when demanded?
Open centred.
What type of oil container - should you replenish an aircraft with?
Unopened.
What viscosity do we want hydraulic fluid to have?
Low viscosity.
What colour is mineral hydraulic fluid?
Red.
If there is a purple puddle under . Your aircraft what is it?
Hydraulic fluid.
What is a bonus of hydraulic systems in regards to energy?
Very little energy lost in the processes.
Is hydraulic fluid corrosive?
Yes, very.
What is the range of hydraulic pressure in modern aircraft?
3000 → 4000 psi.
What should you do to the power transfer value if there is a lease in one of the hydraulic systems.
Close it.
What type of valve uses a ball and spring? (NV valve)
Non return valve
During the aircraft walk around what level would you expect to see the hydraulic resouvior at??
Almost full
Why is the hydraulic resouiour under high pressure?
To reduce evaporation.
What property does nitrogen gas have that means it is used in a hydraulic accumulator?
It is inert.
When are accumulators used for hydraulic pressure? To do with the pumps.
If the pump fails.
What type of delivery pump goes hand in hand with the automatic cut out value?
Constant delivery pump
True or false : In constant pressure pumps, the pump output is dependant on speed.
False.
On start up of an engine, the pump swash playe is at what degree?
Zero.
How many microns is the size of debris a hydraulic filter can stop?
5 microns.
What valve allows for the most appropriate supply to be used in hydraulics?
Shuttle valve.
Hydraulic fuses close when there is a pressure blank.
When there is a pressure differential?
