Hydraulics 1 Flashcards
(135 cards)
1
Q
Advantages of hydraulic systems
A
weight action maintenance and efficient
2
Q
Disadvantages of hydraulics systems
A
Leakage and contamination
3
Q
applied to a liquid causes liquid to expand and exert pressure
A
heat
4
Q
transmitted undiminished in all directions
A
pressure
5
Q
3 basic principles
A
force pressure and working area
6
Q
exerted in pounds
A
force
7
Q
exerted in pounds per square inch
A
pressure
8
Q
expressed in square inches
A
working area
9
Q
pressure exerted on an enclosed liquid is transmitted equally and undiminished in all directions and acts with equal force on all areas
A
pascal’s law
10
Q
MARCH
A
Manual bypass valve Actuating cylinder Reservoir Check valves Hand pump
11
Q
located in the return line stops fluid when closed
A
Manual bypass valve
12
Q
receives fluid pressure and transforms linear mechanical motion
A
Actuating cylinder
13
Q
tank that holds the supply of fluid
A
reservoir
14
Q
unit creates flow of fluid
A
hand pump
15
Q
allows fluid flow in one direction only
A
check valves
16
Q
the presence of undesirable foreign matter that may or may not be visible to the unaided eye
A
hydraulic fluid contamination
17
Q
to achieve and maintain a satisfactory level of purity in hydraulic systems thereby providing for the safe efficient operation of naval aircraft and support equipment
A
hydraulic fluid contamination control program
18
Q
particulate contamination may result from internal wear and failure of system components, maintenance malpractice, or poorly maintained support equipment
A
contamination sources
19
Q
2 classifications of contamination
A
particulate and fluid
20
Q
principle causes if wear in hydraulic pumps, actuators, valve, and servo valves
A
particulate contamination
21
Q
3 parts of particulate contamination
A
organic solids
metallic solids
inorganic solids
22
Q
4 types of fluid contamination
A
air
water
solvent
foreign
23
Q
may be introduced through improper maintenance or a result of system design. can cause fire inside
A
air
24
Q
adversely affect by dissolved, emulsified, or free water. separates from fluid and collects in filter bowls, and other critical locations
A
water
25
is a special form of foreign fluid contamination in which the original contaminating substance is a chlorinated solvent
solvent
26
generally the result of lube oil, engine, fuel, or incorrect hydraulic hydraulic fluid having been introduced inadvertently into the system during servicing
foreign
27
output greater than input required
mechanical advantage
28
Hydraulic system
sharp
29
SHARP
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Selector valve
Hydraulic lines
Actuating cylinder
Reservoir
Pump
```
30
hold supply fluid
provide space for thermal expansion
provide a means for bleeding air
Reservoir
31
create flow of fluid
draw fluid from the reservoir and send it out the system
primarily source of hydraulic power
Pump
32
to direct flow of fluid to and from actuating units
Selector valve
33
converts fluid energy into linear mechanical motion
actuating cylinders
34
converts hydraulic pressure into rotary mechanical motion
hydraulic cylinders
35
the medium for transmitting the fluid from one component to another
hydraulic lines
36
to protect internal parts of the cage from damage due to shocks and surges in the system
snubber
37
Fluid Characteristics
low viscosity
lubricating qualities
corrosion stability
38
viscosity is the resistance of a fluid to flow. viscosity of hydraulic fluid should be low and constant
low viscosity
39
the units in a hydraulic system are self-lubricated by the fluid flowing through them. it is necessary that the fluid has good lubrication qualities
lubricating qualities
40
hydraulic fluid must resist oxidation and inhibit corrosion
corrosion stability
41
to transmit energy
fluid
42
are used in naval aircraft and ground support equipement
synthetic based fluids
43
primary fluid fire-resistant type of fluid
MIL-PRF-83282
44
primarily used as a preservative for a hydraulic system in storage
MIL-H-46170
45
is to hold a supply of fluid for the system
reservoir
46
are not adapted to high-altitude flight or violent manuvers
non-pressurized
47
made of corrosion resistant metal and has a filler neck to provide a means of filling the reservoir with fluid
filler neck and housing
48
return port and the pump supply port
ports
49
inside of the tank in such a manner as to clean all returning fluid
filter
50
to prevent fluid flowing directly from the return line to the outlet of the pump and also to reduce surging and vortexing
baffle
51
electronic particle counter are the preferred method for measuring particle contamination
particle counters
52
size of the particulate matter in hydraulic fluid is measured in
microns
53
alternate method to measure hydraulic fluid contamination
patch testing
54
is to remove foreign matter from the contaminated fluid itself
decontamination method
55
four basic methods
re-circulation cleaning
purifying
flushing
purging
56
to create a flow of fluid
| location is determined by its source of power
hydraulic pump
57
Pump displaces the same quantity of fluid on each revolution
Constant displacement pump
58
Pump contains it’s own regulating device and can change pump displacement to meet the needs of the system
Variable displacement
59
A constant displacement pump that consist of two mashed years, which revolve in a housing. One gear is driven by the driveshaft, the other is a driven gear
Gear pump
60
Hand pump, double action pump, Vickers seven piston, and Vickers nine-piston
Piston pump’s
61
Provides an emergency means of operating hydraulic units in the event of failure of the main pump, through two check valves
Hand pump
62
Discharges fluid to the line of backstroke and forward stroke
Double action pump
63
Is a constant displacement pump that consist of a housing, a rotating group, and a valve plate
Vickers seven piston
64
Is a variable displacement pump that consist of a housing, a rotating group, a valve plate, a yoke, and a pressure control assembly
Vickers nine piston
65
Pump repair I level replacement of gaskets o level
Maintenance
66
To prevent damage to the power source of the pump in the event of the pump binding
Shear shaft
67
Allows the reservoir to breathe
Vent line
68
To show the fluid level in a reservoir
Fluid level indicators
69
Ensure a constant fluid flow to the pump
Pressurized reservoir
70
Regulator maintains a constant air pressure
Air fluid separated
71
Can be installed anywhere before the pump and a hydraulic system
pressurized reservoir
72
Is a primary concern is servicing hydraulic reservoir’s
Cleanliness
73
Is located on or near reservoir that contains the following detailed info necessary. Fluid type, reservoir capacity, and caution notes
A plachr or Information plate
74
To protect the hydraulic system from damage that could result from excessive pressure, caused by failure of the pump regulating devices, thermal expansion, and pressure surges
Hydraulic relief valves
75
Relieve excessive pressure caused by thermal expansion
Thermal relief valves
76
To protect the hydraulic system from excessive pressure by releasing hydraulic fluid from the pressure line into the return line
Main system relief valves
77
The inlet and outlet bodies are threaded together around the valve sleeve
Housing
78
A finish surface and acts as the cylinder chamber for the piston
Valve sleeve
79
Contains the poppet valve that consist of the poppet, poppet Spring, cage, and adjusting nut
Inlet body
80
Contains the spigot, load spring, and piston
Outlet body
81
When the pressure of the hydraulic system reaches the opening pressure setting, and fluid flows through the valve into the return line
Opening
82
When the pressure of the hydraulic system drops to the receding pressure and fluid flow through the valve ceases
closing
83
When the pressure at the outlet port exceeds the pressure at the end report and fluid will flow to the pressure line
Free reverse valve
84
On relief valves is limited to checking the valves for external leaks, proper relieving pressure if a relief valve failed to operate properly. Must be replaced
Maintenance
85
Three parts of a hydraulic filter
Head assembly, filter element, and bowl
86
Is to filter the fluid of the hydraulic system of foreign particles and contaminative substances
Hydraulic filters
87
Nearest element in use, made of organic and inorganic fibers, bonded by proxy resin, with a metal screen on both sides to protect the system. 1 to 10 microns
5 micron disposable filter
88
Made of stainless steel wire mash, can be cleaned and reused. 15 to 25 µm
Stainless steel filter
89
Made of chemically treated paper formed in convolutions, or accordion please, to increase filter capability. 10 to 20 µm
Micronic filter
90
Consist of Minuet bronze balls join together as one piece, but still remaining porous. 25 microns
Sintered filter
91
Provides information on servicing filters of aircraft hydraulic systems
Maintenance instructions manual
92
Provides inspection information and changing intervals of filters
Maintenance requirements cards
93
Provides cleaning and testing information for filter elements
Aviation hydraulics manual
94
Made only at I level
Adjustments
95
Check for proper operation and check for external leakage
Installing
96
Ensure that the pressure in the hydraulic system has been relieved
Removal
97
To store hydraulic fluid under pressure for normal and emergency use
Hydraulic accumulators
98
Aid pump at peak low demand
Normal
99
If the pressure of the main system is lost, fluid that is stored under pressure in an accumulator of a sub system maybe used to actuate that subsystem
Emergency
100
Absorbs shock and surges of fluid within plants and absorbs thermal expansion
Function
101
Pressure line, screen disc, fluid chamber, diaphragm, nitrogen chamber, air valve cap
Spherical or diaphragm
102
Chromium plated on inside end cap , fluid port, Barrel , piston, O-ring package and back up ring, and nitrogen port
Cylindrical or piston
103
React to changes in the fluid pressure of the system
Accumulators
104
Referred to ____To determine proper preload of the accumulator, standard removal or installation procedures, and other important instructions
Maintenance Instruction manual
105
To reduce the pressure of the main system to a predetermined lower pressure in the subsystem
Pressure reducing valve
106
Any pressure alarm of the main system just prior to the pressure line of the subsystem
Location of the pressure reducing valve
107
Body and ports, sleeve and Shuttle assembly, relief valve spring, and a cap
Components of a pressure reducing valve
108
Retaining flange, o ring gaskets, and sleeve holes
Sleeve
109
Inner bore, seat, metering groove, Shuttle holes
Shuttle
110
Determines the amount of reduced pressure in the subsystem
Relief valve spring
111
Screws onto the body and hold the relief valve spring in the housing and an adjustment screw is Incorporated in the cap
Cap
112
The shuttle is held in the unseeded position by the relief valve spring
Open position of the pressure reducing valve
113
When pressure in the subsystem reaches its setting, the relief valve spring is over come
Balanced position of the pressure reducing valve
114
Nitrogen pressure in an accumulator
Preloading
115
Examine accumulators for external and fluid nitrogen leaks detect nitrogen leaks by brushing with soapy water, loosen air valves to check for internal leaks
Inspection
116
The majority of accumulators enable aircraft are equipped with a gauge to check the preload
Pressure gauge method
117
If the pressure of the subsystem becomes too great, the relief valve springs should be compressed further by the shuttle, and excessive pressure will be relieved by allowing fluid to be routed to the return port will relieve excessive pressure
Relief flow operation
118
Referred to maintenance instruction manual if pressure reducing valve operates in properly
Maintenance
119
Hydraulic system pressure must be the depressurized
Safety precautions
120
Is to direct a fluid fluid to and from the actuating cylinder
Solenoid operated selector valve
121
Body, sleeve, slide
Components of a solenoid operated selector valve
122
Cast aluminum alloy that contains four fluid ports; pressure, return, and two cylinders
Body
123
Hollow still sleeve inserted into the body bore. Pattern of holes have been drilled around it
Sleeve
124
Seated inside the hollow sleeve
Slide
125
Pressure that is obtained from the pressure port
Bleed pressure
126
to control bleed pressure is the function of
To opposed solenoid
127
Metal core, That is placed in the hollow center of the solenoid
Plunger
128
Directly under the plunger
Plunger pin
129
Located directly below each plunger pin
Ball
130
One solenoid has been removed and a pug is installed in the solenoid cavity, one coil spring has been removed and an extended in Has been put in its place, and a double spring has been installed on the opposite end of the slide
Three-way, two position
131
To convert hydraulic pressure into linear mechanical motion
Hydraulic actuating cylinders
132
One in which fluid pressure may be directed to only one side of the piston
Double acting unbalanced
133
Piston rod extending through the piston and out through both ends of the cylinder
Double acting balanced
134
Inspect for signs of leakage, and take corrective actions, X ternal leakage is the most common trouble encountered
Maintenance
135
To convert hydraulic pressure into Rotary mechanical motion. The direction of the rotation is controlled by selector valve
Hydraulic motors
