Pneumatics.ppt

Pneumatics Technology

• Air is used as a medium to transmit power

ADVANTAGES:

• Low Cost as compared to other systems

• Choice of Movement i.e linear and rotory

• Storage of compressed air is easy

• Reliability

• Speed Control

• Simple in design and control

• Safety

• Clean System

Pneumatics Applications Operation of Heavy Doors

Clamping Operations

Pick & Place Operations i.e Material Transfer

Shearing & Punch Presses

Forming Operations

Machine tools, work or tool feeding

Pneumatic Robots

Bottling & Filling Machines

MAIN COMPONENTS

• A source of energy supply i.e. Air Compressor

• Air Receiver

• Air Cleaning/ conditioning system

• Pipe Network

• Pressure Control Elements

• Flow Control Elements

• Direction Control Elements

• ACTUATORS ( for delivery of mechanical work)

Displacement Compressors

Reciprocating Rotary

Diaphragm(3-5 bar)

Free from OilFood, Pharma Inds.

Vane ScrewPiston

(3 -7 bar range)

• Compressor Rating – described as displaced volume

• Q (lt/min) = piston area x stroke length x number of cylinders x rpm

• Specific Energy Consumption –

1 kW of electrical energy is needed for production of 120 -150 l/min of compressed air at 7 bar .

• Pressure Rating –

SI Units - Pascal (Pa) , 1 Pa = 1 N/m2

Metric Units – bar , 100,000 Pa = 1 bar OR

kgf/cm2 , 1 kgf/cm2 = 0.98066 bar , = 14.22 psi

English Units – lbf/sq. inch (psi), 1 bar = 14.5 psi

AIR RECEIVER

FUNCTIONS

• Store sufficient amount of air.

• Cooling of air

• Oil separation

• Moisture Condensation

SIZING AIR RECEIVER

Air receiver Capacity = Compressor output of compressed air/min.

(Not Free Air Delivery)

EXAMPLE:

Compressor Delivery = 18 m3/min (free air) at 7 bar

COMPRESSED AIR OUTPUT = 18000/7 = 2500 litres (approx) = RECEIVER SIZE

ACTUATORS

DIRECTIONAL CONTROL VALVES

FORWARD

BACKWARD

NEED OF A DCV ?

DIRECTIONAL CONTROL VALVES

• Determines the direction of air flow.

• Described in terms of –

Number of Ports

Number of Positions

Normal Position

Method of Actuation

DIRECTIONAL CONTROL VALVES

DIRECTIONAL CONTROL VALVES

DIRECTIONAL CONTROL VALVES

DIRECTIONAL CONTROL VALVES

DIRECTIONAL CONTROL VALVES

DIRECTIONAL CONTROL VALVES

DIRECTIONAL CONTROL VALVES

DIRECTIONAL CONTROL VALVES

DIRECTIONAL CONTROL VALVES

DIRECTIONAL CONTROL VALVES

DIRECTIONAL CONTROL VALVES

DIRECTIONAL CONTROL VALVES

METHODS OF ACTUATION

Manual

Pneumatic Pilot

Solenoid

Solenoid Pilot

CHECK VALVE

TWIN PRESSURE VALVE

• AND LOGIC Device

SHUTTLE VALVE

QUICK EXHAUST VALVE• Allows increased speed of piston by exhausting the cylinder directly to its port

FLOW CONTROL VALVE

FLOW CONTROL VALVE

TIME DELAY VALVE

TIME DELAY VALVE