Pneumatics Ppt

Basic Components of Pneumatics & Applications

ByK. Sai VishnuK. Nagarjuna

Overview

Introduction

Transmission of Energy

Receiver Tank

Valves

Cylinder

Applications

Introduction

Meaning: Pneuma+Tics

Study of systems operated under air

pressure

Advantages:

1. Components are lighter

2. Air is cheap

3. Explosion proof

4. Easily transportable

5. Variable speed

Transmission of energy Accomplishment of work requires the application of

kinetic energy.

In a Pneumatic system, energy is stored in a

potential state.Compressor

Filters

Pressure Switch

Safety Relief Valve

Pressure Regulator

Valves

Receiver Tank

Cylinder

Positive Displacement Compressor Parts:

1. Movable member2. Piston3. Crank shaft4. Inlet & Outlet ports

Functioning:

1. As the crankshaft pulls the piston down, an increasing volume is formed within the housing

2. When pressure differential between the compressor chamber and discharge line is high enough, the discharge valve opens, leading to outlet

Bicycle Pump

Control of Pressure and Energy Energy:

1. If energy is not under control, useful work will

not be done and machinery or machine

operators might be harmed

2. Energy can be controlled relatively easily by

using valves.

Pressure:

1. Control of pressure is a crucial task in

pnuematics.

2. Control of pressure is required after the

compressor as a safety for the system

3. Control of pressure after an air receiver tank is

necessary so that an actuator receives a

steady pressure

Filters

A Pneumatic filter is a device which removes

contaminants from a compressed air stream

By using a "media" type that traps particulates filtering

can be done. Primary Pneumatic

filters will remove

particles as small as 5

micrometres from the

air.

Secondary filters are

used for a variety of

applications and can

remove particles as

small as 50 nanometres

in size

Components of Compressor Filters:

1. They consists of, series of filer apparatus that remove the dust

2. Removal of dust is required to avoid damage to the components

Pressure switch:1. System pressure is sensed with a spring-loaded

piston 2. Electrical signals are used3. As pressure in the receiver tank rises, it forces the

piston upward Safety relief valve:1. Failure of a control system to function properly, a

positive displacement compressor system is generally equipped with a safety relief valve.

2. A spring holds the poppet firmly on its seat

Safety Relief Valve

Pressure Switch

Receiver tank1. Energy delivered by a compressor is stored in air

receiver tank in the form of compressed air.2. Intermittent compressor operation in this manner is a

power saving benefit for the system.

Pressure regulator

1. A pressure regulator is positioned after a receiver tank and is used to portion out this stored energy to each leg of the circuit.

2. Air from the receiver can flow through the valve to a point downstream.

Pressure Regulator

Receiver Tank

Valves control the switching and routing of the air in a pneumatic system. Valves have to control the flow of compressed air, they also have to control the flow of exhaust air to the atmosphere.

There are two main types of valves used in pneumatic switching circuits, the 3/2 valve and the 5/2 valve.

1 2

3

2

1 3

4

5

Valves

The 3/2 valve is used to control

items such as single acting

cylinders which have a single

input. t to atmosphere.

The number 3 signifies that the

valve has three ports, whilst the

number 2 signifies that the valve

has 2 directions or states

.

3/2 Valve

The 5/2 valve is used to control

items such as double acting

cylinders which have two inputs.

The number 5 signifies that the

valve has five ports, whilst the

number 2 signifies that the valve

has 2 directions or states.

AIR PRESSURE SOURCE

EXHAUST AIR RETURN

EXHAUST AIR RETURN

PRESSURE OR MECHANICAL FORCE

PRESSURE OR MECHANICAL FORCE

5/2 Valve

OR- Shuttle valveThe “OR” element, or

Shuttle valve, is used whenever at least one of several different signals is required without exhausting that signal through the exhaust ports of the other devices.

Input 1 Input 2 Output

0ff 0ff 0ff

on Off On

Off On On

On On on

AND- Shuttle valve

The “AND” element, for multiplication functions, is used whenever 2 or more signals are required to be present before the desired function can begin

Input 1 Input 2 Output

0ff off 0ff

off 0n 0ff

0n off 0ff

on on on

www.PneumaticFanatics.org FIRST Kickoff - 2007 jrg

Valves are in Control Control Pressure

Relief Valves & Regulators Control Flow

Check Valves (used on compressor)

Flow Controls

Needle Valves

Flow Control Valve

This valve is also known as speed control valve Allows free flow in one direction but restricts flow in the other direction In the valve shown the free movement of air is from right to left and controlled flow is from left to right.Screw in this works just as a nozzle in a water pipe The air speed can be adjusted by using screw Defect:speed of the air will be deceased by minimum 5%

The Pneumatic Cylinder or Linear

ActuatorSpeed Valve Piston and

Rod Clevis

One Touch Quick Connect FittingCylinder

BodyPneumatic Mounting BracketCylinder Force = Pressure x

Piston Area

In a single acting cylinder, the piston is forced out by the pressure of the air. When the air supply is removed and the air inside the cylinder is allowed to escape, the piston moves back, driven by the force of a spring.

S Single Acting Cylinder

The double acting cylinder has two air connections. When compressed air is applied to one connector and the other connector is allowed to exhaust to atmosphere (i.e.. the air is allowed to escape freely), the piston is driven to one end of the cylinder. This type of cylinder gives greater power on the return stroke than the single acting cylinder, and also ensures that the piston is effectively locked in position at both ends of its stroke.

Double Acting Cylinder

Transmission of air

1.When the air supply is given to the valve, it will be directed in such a way that ,it helps for the positive displacement of the piston

2. During the negative displacement of the piston, the air coming out of the cylinder will be directed to the exhaust of the valve and passed out.

How to actuate the Double Acting Cylinder, so that the user can vary the speed of the cylinder , depending on his use ?

Try the circuit

Single Acting Cylinder Double Acting Cylinder 3/2 Push button valve 3/2 lever Flow Control Valve Or- Shuttle Valve And- Shuttle Valve 3/2 Valve 5/2 Valve


Try the circuit



Try the circuit



Try the circuit



Try the circuit



Try the circuit



Try the circuit



Try the circuit



Try the circuit



Try the circuit


ExplanationTo vary the speed , we have to use Flow Control Valve We have to use two 3/2 Push Button Valves, since one has to assigned to flow control valve

Perfect answer

ExplanationTo vary the speed , we have to use Flow Control Valve We have to use two 3/2 Push Button Valves, since one has to assigned to flow control valve

Wrong Answer

There are many applications of Pneumatics , some of them are:

1. Pneumatics can be used to separate objects from a bulk of objects

Example: This application is used in iron and bread industry.

2. Pneumatics can be used to rotate objects.

Applications of Pneumatics

How to create artificial blood?

The method by which artificial blood is created using pneumatics is Pneumatic Dust System Components required are: Air line tubi

ng, Permanent air red liquid , Compressed air duster, Tape

. Since we are using permanent liquid care should taken , otherwise red colour will spoil the clothes

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Pneumatics Ppt