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20 Cards in this Set
- Front
- Back
What materials form the bases of the three types of hydraulic fluids? |
Vegetable, mineral, and phosphate-esters |
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What colors do you notate mineral-based and phosphate ester based hydraulic fluids? |
Mineral-based fluids are red and phosphate ester based fluids are light purple |
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what are the results of exposing lacqueurs, oil-based paint, plastic resins, and final compounds to phosphate ester based hydraulic fluid? |
Material will be damaged and/or softened, or the paint will peel |
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Name several sources used to develop hydraulic pressure |
Hand pumps, engine driven pumps, and electrically driven pumps |
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What would cause the bypass valve in a hydraulic filter to open and allow unfiltered fluid to circulate in the system? |
A clogged filter element |
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Describe several methods of pressurizing a hydraulic reservoir |
Engine bleed air, system pressure acting on a small piston in the reservoir, using variable displacement hydraulic pumps |
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What feature prevent engine damage if an engine driven hydraulic pump seizes or is overloaded? |
A shear section in the pump drive shaft will break, disconnecting the pump from the engine |
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Describe the purpose of a pressure relief valve |
Pressure relief valves limit the maximum pressure produced by the pump, thereby preventing failures of the system components |
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Engine driven pumps delivered the output fluid flow in what two forms? |
As a constant volume or a variable volume |
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Describe the operation of a gear type pump |
the two meshed gears, driven by a power source, rotate in housing, inlet fluid is carried around the outside of the gears and delivered to the outlet side as the gears rotate |
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Describe the purpose of a pressure regulator |
pressure regulators manage the output of the pump to maintain system pressure. They allow the pump to be unloaded so it turns without significant resistance |
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What is the device that is used in some systems to supplement the pump outlet during periods of high demand |
An accumulator |
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What are the three different types of accumulators? |
Piston, diaphragm, and bladder |
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What safety precautions must be taken prior to disassembling an accumulator? |
Release all of the air or preload |
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When hydraulic unit is replaced, what precaution should be taken to avoid contamination of the system? |
All lines should be capped or plugged immediately after they are disconnected |
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What types of components or systems are pneumatically operated in some aircraft? |
Landing gear, brakes, flaps, and other mechanical actuators |
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Name several sources of pneumatic power |
Storage bottles, engine bleed air, engine-driven compressor or vane type pumps |
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What happens to excess pressure in a pneumatic system? |
A relief valve vents in overboard |
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What is the function of a restrictor in a pneumatic system? |
To control the rate of flow of the JSAT |
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What are the reasons for periodically purging a pneumatic system? |
To remove moisture and contaminants |