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LOGO

VALVES

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LOGO

VALVES 

Definition of valves. Types of valves.

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What is a valve? 

A valve is a device that controls the flowof a fluid .

Importance.

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Types of Valves

Multi-Turn Valves or Linear Motion Valves The Gate Valve

The Globe Valve

The Diaphragm Valve

The Needle Valve

Quarter Turn Valves or Rotary Valves The Ball Valve

The Butterfly Valve

Self-Actuated Valves The Check Valve

The Pressure Relief Valve

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Multi-Turn Valves or Linear Motion Valves

The Gate Valve used primarily for on- off,

non-throttling service.

closed by a flat face, vertical

disc, or gate that slides downthrough the valve to block

the flow.

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Multi-Turn Valves or Linear Motion Valves

The Globe Valve Closed by a plug with a

flat or convex bottomlowered onto amatching horizontal

seat located in thecenter of the valve.

Raising the plug opensthe valve, allowing fluidflow.

used for on--off serviceand handles throttlingapplications 

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Multi-Turn Valves or Linear Motion Valves

The Diaphragm Valve closed by means of a

flexible diaphragm

attached to a

compressor.

handles corrosive,

erosive and dirty

services.

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Multi-Turn Valves or Linear Motion Valves

The Needle Valve a volume-control valve that

restricts flow in small lines.

The fluid passes through anorifice that is the seat for a

rod with a cone-shaped tip. The Size of the orifice is

changed by positioning thecone in relation to the seat. 

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Quarter Turn Valves or Rotary Valves 

The Ball Valve uses a rotating ball with a

hole through it that allows

straight-through flow in the

open position and shuts off flow when the ball is rotated

90 degrees to block the flow

passage.

used for on--off and throttling

services. 

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Quarter Turn Valves or Rotary Valves 

The Butterfly Valvecontrols flow by using a

circular disc or vane withits pivot axis at right

angles to the direction of flow in the pipe.

used both for on-off andthrottling services. 

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Butterfly valve

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Self-Actuated Valves

The Check Valvedesigned to prevent 

backflow. Fluid flow

in the desired

direction opens thevalve, while

backflow forces the

valve closed. 

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Self-Actuated Valves

The Pressure Relief Valve designed to provide

protection from over-

pressure in steam, gas, air 

and liquid lines.

"lets off steam" when safe

pressures are exceeded,

then closed again when

pressure drops to a preset

level.

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Control Valves

The Control Valve designed specifically as control

valves. 

designed to ensure accurateproportioning control of flow.

automatically varies the rate of flow based on signals itreceives from sensing devicesin a continuous process.

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 Applications of valves

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