Hydraulic Components

1
Hydraulic Components

• Advanced Hydraulics
• Don Gilliland

2
Hydraulic Components

• Reservoirs
• Accumulators
• Pumps
• Valves
• Actuators
• Conductors

3
Hydraulic Components

• Reservoir Functions
• Fluid Cooling
• Contaminates to settle
• Air to escape
• Volumetric variance during Actuator operation
• Heat Expansion

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Reservoir Considerations

• Atmospheric Venting
• In many fluid power systems, the only force
  acting on the hydraulic fluid to move fluid to
  the pump is the force of atmospheric air
  pressure. The vent in most fluid power reservoirs
  is thus critical. The fluid cannot flow out if
  the air cannot flow in. It is through the
  reservoir vent that atmospheric air pressure is
  applied on the hydraulic fluid.
• Volumetric variance during Actuator operation
• Single and two way single rod cylinders both
  require different fluid volumes during system
  operation. The reservoir volume must allow for
  this variance.

5
Reservoir Considerations

• Volumetric variance during 1 way Actuator
  operation
• During advancing a controlled distance to the
  right
• More fluid volume into cylinder from reservoir
• Air only is forced out through a breather
  (Reservoir must lower)

breather
6
Reservoir Considerations

• Volumetric variance during 1 way Actuator
  operation
• During retracting to the left under load down
  force
• More volume out back to reservoir
• Air must go in breather (Reservoir level Raises)

breather
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Reservoir Considerations

• Volumetric variance during 1 way Actuator
  operation
• Breather must have filtration
• Keeps contaminates out of cylinder chamber and
  away from piston seals
• Reservoir level change can be quite large

breather
8
Reservoir Considerations

• Volumetric variance during 2 way Actuator
  operation
• During advancing a controlled distance to the
  right
• More volume in than volume out
• Due to Rod volume on right side

9
Reservoir Considerations

• Volumetric variance during 2 way Actuator
  operation
• During retracting same controlled distance to the
  left
• More volume out than in
• Due to Rod volume on right side

10
Reservoir Considerations

• Fluid Cooling
• Heat is generated in hydraulic fluid from
  component motion and friction and when pressure
  forces molecules of fluid together. These
  molecules begin to rub on components and one
  another, generating friction and heat. The
  reservoir should be made of a heat dissipating
  material and be large enough to allow some motion
  slowing time to allow heat dissipation.
• Contaminate Settling
• The reservoir should be large enough to allow
  some motion slowing time to allow contaminate
  settling during the fluid cooling process.

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Reservoir Considerations

• Fluid Cooling ?

12
Reservoir Considerations

• Contaminate Settling

13
Reservoir Considerations

• Fill cap may be filtered breather and need
  periodic cleaning

14
Reservoir Leaks
15
Reservoir Leaks

• A leaky or overrunning reservoir can spill
  hydraulic fluid.
• The mess
• DOT or EPA ramifications
• Hydraulic fluid may be caustic with other vehicle
  system materials
• Tires, brake linings, drive belts, wiring,
  insulation, and even Wheels or Battery Cases can
  be damaged by some hydraulic fluids.

16
Hydraulic Components

• Reservoirs
• Review
• Next Accumulators
• THE END