1. Forging new generations of engineers
Fluid Power
Principles of EngineeringTM
Unit 4 - Lesson 4.3 – Fluid Systems
Forging new generations of engineers
Project Lead The Way, Inc.
Copyright 2007

2. Fluid Power

3. What is Fluid Power ?
A system that transmits and controls energy through the use of pressurized liquid or gas
Pneumatics - the media used is air
Hydraulics - the media used is oil or water

4. What can Fluid Power Do ?
Operation of system valves for air, water or chemicals
Operation of heavy or hot doors
Unloading of hoppers in building, steel making, mining and chemical industries
Ramming and tamping in concrete and asphalt laying

5. What can Fluid Power Do ? Lifting and moving in slab molding machines
Crop spraying
Paint Spraying
Holding and moving parts or assemblies in manufacturing

6. What can Fluid Power Do ?
Jig (guides cutting tool) and Fixture (stationary work holding) clamping
Forming operations of bending, drawing and flattening
Bottling and filling machines
Machine tool changing

7. What can Fluid Power Do ? Component and material conveyor transfer
Robots
Dentist drills
vacuum lifting for thin sheet materials
and much..much..more

8. Properties of Compressed Air
Components have long working life resulting in longer system reliability
Environmentally friendly
Safety issues are minimized e.g.. Fire hazards; unaffected by overloads (actuators stall or slip)
pneumatic actuators in a system do not produce heat (except for friction)

9. Properties of Gases Three important variables
1. Temperature, T
2. Pressure, P
3. Volume, V
Gas laws describe relationships between these variables

10. Properties of Gases - Bernoulli’s Law
When there is fluid flow through a tube of varying diameters
the total energy in the system is constant
the velocity is inversely proportional to the pressure
V1 is less than V2
P1 is higher than P2

11. Properties of Gases (Boyle’s Law)
The pressure of a given mass of gas is inversely proportional to its volume (providing the gas remains at constant temperature)
Isothermic (equal temperature)

12. Properties of Gases (Boyle’s Law)

13. Properties of Gases (Charles’s Law)
When the pressure of a confined gas remains constant, the volume of the gas is directly proportional to the absolute temperature.
A given mass of gas increases in volume by 1/273 of its volume for every degree Celsius rise in temperature or 1/459.7 for every degree Fahrenheit rise in temperature.
e.g. Hot air balloon

14. Properties of Gases (Charles’s Law continued)
Isobaric - equal pressure
V1 = T1
V T2
Where:
V1 = initial volume
V2 = resulting volume
T1 = initial absolute temperature
T2 = resulting absolute temperature
A volume of air in an accumulator is submerged in a bucket of ice water (32 degrees F). If you remove the accumulator from the ice water and place it in a bucket of boiling water what would the resulting volume be.
Fahrenheit
Absolute is 460 +
V2 = V1 x 672
492
V2 = V1 x T2 T1 =
1.36 V1

15. Properties of Gases (Pascal’s Law)
Pressure at any point in a closed body of fluid is the same in all directions, exerting equal force on equal areas.
Where:
F = force
P = pressure
A = area
F = P x A F P A
Cover the letter you are trying to solve for
e.g. P=F/A