Hydraulics Flashcards
Pressure, force, area triangle
- force is weight usually lbs
- pressure is psi
- area is just that pie x d2 divided by 4

Power supplies
-prime mover (electric motor) -pumps -reservoir
Control Device
-directional -pressure control -flow control
Output
-actuator (rotary/linear) -loads
Pressure
- the force on a unit of area
- pressure decreases when flow is increased
- produced by resistance to flow
Pascall’s Law
-relation between force, pressure & area -remember triangle
Pressure creation
-resistance to flow -not a pump, pump creates flow
Intensifiers
-contained fluid in two different areas in a cylinder -used to efficiently generate a high pressure fluid -output pressure is considerably greater than input pressure.
Atmospheric Pressure
-how much weight is sitting on you right now from the air, etc… -14.7 psi at sea level
Differential Cylinders
-cylinders with different areas on each side of piston -remember the area loss from the rod
Non-differential cylinders
-areas on each side are the same -most two Rod cylinders
Load Capacities
-the larger the area, the larger the force for the same pressure
Extension
-on extension, the pressure acts on the area of the piston
Retraction
-on retraction the pressure is the piston area minus the rod area (annulus area)
Advantages of Hydraulics
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Disadvantages of Hydraulics
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2 to 1 cylinder
-the cross section area of the rod occupies exactly half the area of the cap end side
Flow
-movement of a liquid produced by a pump or a pressure drop across a hole -the greater the pressure difference across a hole the greater the flow -the ratio of units/time. It can be expresses as velocity (ft/min, ft/sec) -flow info a differential cylinder does not equal flow out
Flow Triangle
- speed/flow/area relationship
- V/t or Q stands for flow in cubic inches/minutes only -S stands for the speed in inches/minutes
- A stands for the area in squares inches

Hydraulic Intensifier Math Question
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Hydraulic Cylinder Math
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Porta Power Math
-Steps