pneumatic System Component

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CONTENTS

INTRODUCTION

PNEUMATIC SYSTEM COMPONENTS

FUNCTIONS OF PNEUMATIC SYSTEM COMPONENTS

1. PNEUMATIC ACTUATOR

2. COMPRESSOR

3. AIR RESERVOIR

4. PNEUMATIC VALVES

DIFFERENT TYPES OF PNEUMATIC SYSTEM COMPONENTS

REFERENCES



INTRODUCTION TO PNEUMATIC SYSTE

COMPONENTS

Pneumatic system: A pneumatic system carries power by empcompressed gas, generally air, as a fluid for transmitting energyan energy-generating source to an energy-using point to accom

useful work.







Compressor

storage reservoir

Control Valves

Direction control valves

Ball Seat valve

Disc seat poppet valve

Non return valves Check valve

Shuttle valve

Quick exhaust valve

Two pressure valve

Flow control valves

Pressure control valves

Solenoid Valve

pneumatic actuator

Linear Actuator

Rotary Actuator

Pressure switch

Piping system

FRL(Filter-Regulator-Lubricator) U



FUNCTIONS OF PNEUMATIC SYSTEM COMPO

1. The pneumatic actuator converts the fluid power into mech power to perform useful work.

2. The compressor is used to compress the fresh air drawn froatmosphere.

3. The storage reservoir is used to store a given volume of compair.

4. The valves are used to control the direction, flow rate and presscompressed air.

5. External power supply (motor) is used to drive the compressor.

6. The piping system carries the pressurized air from one locatanother.



1. PNEUMATIC ACTUATOR

Pneumatic actuators are the devices used for converting prenergy of compressed air into the mechanical energy to performwork.

Actuators are used to perform the task of exerting the required fthe end of the stroke or used to create displacement by the movof the piston.

Pneumatic cylinders can be used to get linear, rotary and oscimotion. There are three types of pneumatic actuator: they are

i) Linear Actuator or Pneumatic cylinders

ii) Rotary Actuator or Air motors

iii) Limited angle Actuators



There are varying designs of single including:

1. Diaphragm cylinder

2. Rolling diaphragm cylinder

3. Gravity return single acting cylinder

4. Spring return single acting cylinder

Single Acting Cylinder

Double Acting Cylinder Based on the cylinder action

Rotating type

Non Rotating type





2. COMPRESSOR

Pneumatic control systesupply of compressed a be made available in sufand at a pressure to suitthe system.

Air compressors are gedisplacement units areciprocating piston typscrew or rotary vane tclassification of compr

below:

Classification of compressors



The air reservoir stores the pressurized air used to

operate the pneumatic circuit components(actuator).

The air reservoir acts like a pneumatic battery

3. AIR RESERVOIR

Air reservoir



4. PNEUMATIC VALVES

Valve are defined as devices to control or regulate the commencemtermination and direction and also the pressure or rate of flow of a flunder pressure which is delivered by a compressor or vacuum pump ostored in a vessel.

Valve available for pneumatic control can be classified into four princgroups according to their function:

a. Direction control valve (DCV)

b. Non return valves (NRV)c. Flow control valves

d. Pressure control valves





Disc seat poppet valve

When push button is released, po

are connected via hollow pushbu

the push button is pressed, port 3

blocked by the moving valve ste

Figure shows the 3/2 DCV



PORT DESIGNATION OF DCV

Ref. ANSI Y32.10, FLUID POWER



MATHOD OF ACTUATION OF DCV

Type of actuation Type of control Symbol

Manual General

Pushbutton

Detent lever operated

Foot pedal





Type of actuation Type of control Symbol

Pneumatic Direct

Indirect, pilot operated

Electrical Single solenoid

Double solenoid



A. CHECK VALVE

B. NON RETURN VALVES

It completely blocks

direction while permi

the opposite direction

minimum pressure lo

valve.



B. Shuttle Valve

It is also known as a double con

double check valve.

A shuttle valve has two inlets an





D. Two Pressure Valve This valve is the pneumatic

valve.

A two pressure valve require

pressurized inputs to allo

output from itself.



C. FLOW CONTROL VALVE

A flow

regulates the

The control a

to the air

through the v

open, maint

volume per

Figure (a) sh

restrictor typ

valve (manifo

(b) shows

restriction ty

valve (inline t

(a) Manifold type (b) Inline type



D. PRESSURE CONTROL VALVE

A. Pressure limiting valve.

It is a standard feature of compressed air pr plant but is hardly ever used in pneumatic contr

These valves perform a safety relief func

opening to the atmosphere if a predetermined p

is exceeded in the system, thus releasing the

pressure.

As soon as the pressure is thus relieved to the

figure, the valve closed again by spring force.



B. Pressure sequence valve C. Pressure reducing valve o

Function of the sequence valve is very

similar to that of a pressure limiting

valve. Outlet of the pressure sequence

valve remains closed until pressure

upstream of it builds up to a

predetermined value. Only then the valve

opens to permit the air from inlet to

outlet. Sequence valve must be

incorporated into a pneumatic control

where a certain minimum pressure must

be available for a given function and

operation is not be initiated at any

pressure lower than that.



Solenoid Valve

• Solenoid valves are electrically operated valves that

control the direction and flow of pressurized air to and

from pneumatic actuators or circuits.

• Solenoid valves can be either mono-stable, (they

spring return to a default condition either on or off ) or

Bi-stable, (having no preferred or default conditionthus remaining where it was last positioned either on

or off ) Pneumatic valves can be operated by hand,

(mechanical) electrically (solenoid) or air (piloted)

operated.



Regulator

• The function of the air pressure regulator is to

maintain working pressure virtually constant

regardless of fluctuations of the line pressure and air

consumption.

• These devices are fitted with mechanical components

that react to changes in the downstream air pressure.

• The regulator attempts to automatically maintain a

constant (preset) pressure within a pneumatic circuit as

long as the supply (reservoir) pressure is greater than

the required circuit pressure.

• The reading on the regulator-mounted gauge indicates

the regulated or circuit pressure



Pressure switch

A pressure switch is a pneumatic-

converter. Pressure switches are us

change in pressure, and opens or clos

switch when a predetermined pressu

Bellow or diaphragm is used to sense

pressure. Bellows or Diaphragm is use

contract in response to increase o

pressure.



FRL Unit

In most pneumatic systems, the compressed air is first filtered and then regulated

specific pressure and made to pass through a lubricator for lubricating the oil. Thu

filter, regulator and lubricator are placed in the inlet line to each air circuit. They m

installed as separate units, but more often they are used in the form of a combine



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pneumatic System Component