MAGM 262

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MAGM 262
Hydraulic Fundamentals
Mr. Conrado
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Hydraulics- fluid power for the massesMatthew R.
Bono
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Common Examples

• Automobile Brakes

Hydraulic Fluid Pressurized by foot pedal and
booster closes piston, slows rotor and wheel
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Common Examples

• Heavy Machinery

• Videos

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Hydraulic Fundamentals

• Hydraulic systems are everywhere from
• Large excavation equipment
• Steering in your car
• Shocks
• Power trains

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Hydraulic Fundamentals

• Using liquids to transfer force
• They conform to their container
• Practically incompressible
• Apply pressure in all directions
• Flow in any direction through lines and hoses.

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Hydraulic Fundamentals

• Liquids for all practical purposes are
  incompressible.
• When a substance is compressed it takes up space.
  A liquid does not do this even under large
  pressures.
• The space any substance occupies is called
  displacement.

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Hydraulic Fundamentals

• Gases are compressible
• When a gas is compressed it takes up less space
  and its displacement is less. For this reason
  liquids are best used for hydraulic systems.

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Hydraulic Fundamentals

• Hydraulics doing work.
• Pascals law Pressure exerted on a confined
  liquid is transmitted undiminished in all
  directions and acts as a equal force on all equal
  areas.
• Thus a force exerted on any part of a confined
  liquid the liquid will transmit that force
  (pressure) in all directions within the system.
• In this example a 500 pound force acting upon a
  piston with a 2 inch radius creates a pressure of
  40 psi on the fluid.
• Ex For a 2 diameter piston
• Area ?(3.14) x radius squared.
• A 3.14 x (2x 2)
• A 3.14 x 4
• A 12.56
• Pressure Force Area
• P 500lbs 12.5 Sq. In.
• P 40 psi
• This same liquid with a pressure of 40 psi acting
  on a piston with a 3 inch diameter can support
  1130 pounds.

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Hydraulic Fundamentals

• This same liquid with a pressure of 40 psi acting
  on a piston with a 3 inch diameter can support
  1130 pounds.
• Ex For a 3 diameter piston
• Area ?(3.14) x radius squared.
• A 3.14 x (3x 3)
• A 3.14 x 9
• A 28.26
• Force Pressure x Area
• F 40 psi x 28.26
• F 1130.4

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Hydraulic Fundamentals

• Pascals Law
• To understand how this works we must understand a
  very simple but fundamental formula.
• To find one of the three areas two of the others
  must be known.
• Force The push or pull acting on a body usually
  expressed in pounds.
• Pressure The force of the fluid per unit area.
  Usually expressed in pounds per square inch or
  psi.
• Area A measure of surface space. Usually
  calculated in square inches.
• To calculate the area of a circle use the formula
  Area Pi (3.14) x radius squared.
• Ex For a 2 diameter piston A3.14x(2x2) or
  A 12.5 sq. in.

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Hydraulic Fundamentals

• Pascals Law
• With the knowledge of the surface area it is
  possible to determine how much system pressure
  will be required to lift a given weight.
• The pressure needed for a 500 pound given weight
  is calculated with the formula
• Pressure Force Area
• P 500lbs 12.5 Sq. In.
• P 40 psi

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Hydraulic Fundamentals

• Mechanical Advantage
• Here we see and example of how a hydraulic system
  can create a mechanical advantage.
• We can calculate the items in question by using
  the systems known items and Pascals law.
• For system pressure we use PFA
• P 50lps 1sq.in (cylinder 2)
• P 50psi
• Now we know the system pressure we can calculate
  the load force for cylinders 1 3 and the piston
  area for 4. Do so on a separate piece of paper
  and wait for instructions.

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Hydraulic Fundamentals
50psi

• Cylinder One
• Solve for Force
• FP x A
• F 50psi x 5 in²
• Cancel out square inches to leave pounds and
  multiply
• F 250lbs.

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Hydraulic Fundamentals

• Cylinder One
• Solve for Force
• FP x A
• F 50psi x 5 in²
• F 50 pounds/sq inch x 5 sq inches
• Cancel out square inches to leave pounds and
  multiply
• F 50 lbs x 5
• F 250lbs.

250 pounds
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Hydraulic Fundamentals

• Cylinder Three
• Solve for Force
• FP x A
• F 50psi x 3in²
• Cancel out square inches to leave pounds and
  multiply
• F 150 pounds

150 pounds
50psi
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Hydraulic Fundamentals

• Cylinder four
• Solve for Area
• A F P
• A 100 pounds 50 psi
• A 100 pounds 50 pounds/ square inch
• Cancel pounds to get in² and divide
• A 100 50 square inches
• A 2.00 in²

2.0 in²
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Hydraulic Fundamentals
150 lbs
150 lbs
2 in²
Cylinder One FP x A F 50psi x 5 in² F 50
lbs/sq inch x 5 sq inches F 50 lbs x 5 F
250lbs.
Cylinder Three FP x A F 50psi x 3in² F 150
pounds
Cylinder Two PFA P 50 lbs 1in² P 50psi
Cylinder Four A F P A 100 pounds 50
psi A 100 pounds 50 pounds/ square inch A
100 50 square inches A 2.00 in²
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Parts of a Closed System

• Reservoir
• Filter
• Pump
• Valve
• Cylinder
• Lines

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How It Works

• Motor Spins Pump
• Pump Moves fluid
• a. Out of reservoir
• Through filter
• Through Pump
• c. Into valve
• Valve directs fluid to ram
• Pressurized side of ram moves
• Fluid on other side of ram returns to reservoir

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What can change

• How to Power the System
• Elbow Grease- like a automotive jack
• Electric Motor
• Fueled Motors
• gasoline, diesel, aviation anything else
• System Design
• Flow Rates
• Pressures
• Location
• Point of Action

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How it worksHorsepower, Flow Rate and Pressure

• As motor power goes up the pump has more power to
  move fluid
• This can increase flow rate or pressure

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How it works

• Flow Rate
• Hydraulic systems rely on filling a given area
  with fluid
• The more fluid you pump into the area the faster
  the implement moves
• If your trying to float a rubber boat in a
  swimming pool what will do it faster a garden
  hose or a fire hose

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How it works

• Pressure
• Hydraulic systems like the jaws of life can
  create incredible amounts of force
• What shoots further, water from a hose spraying
  a cone or spraying a jet

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Advantages

• Force Multiplier
• Automobile Brakes
• Controllable-
• variable speed and power
• High power low weight-
• Especially air powered
• Very Mobile-
• Harvesting Equipment
• Possibilities-
• Diesel Hydraulic Hybrid Delivery Trucks
• Roller Coasters

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Force Multiplier Automobile Brakes

• The force of your foot can stop an entire car,
  with help from hydraulics

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Controllable-

• Large harvesting equipment can do dozens of
  things at one time all with hydraulic power

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Controllable- Cotton Picker Header
Each row of cotton goes through the picking
zone Each spindle moves independently of the
others while machine moves through field, blows
lint into hopper and discards waste
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Very Mobile

• The jaws of life in the last slide are used by
  hundreds of rescue outfits across the US and are
  readily carried everywhere they go

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Why does it Matter

• Hydraulic systems are in everything from aircraft
  to theater performances in Las Vegas. Someone had
  to design, build and maintain all these systems,
  why couldnt it be you?

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Homework

• Micrometer worsheet

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Lab

• Bottle Jack Lab