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 Home » Insight » Choosing Valve Actuator Power Source Choosing Valve Actuator Power Source  Valv e Ac tuator , based on the power source, falls into the three categories. Each power source of valve actuator has unique characteri stic which provide different advantag e to make it su itable for specific applica tion. 1. Pneumatic Actuator Pneumatic actuator is the most commonly used type due to the cheapest pric e and availabili ty of its power source  i.e. compressed air. The use of natural gas is also applica ble if it is not f easible to install air comp ressor system. It is used both f or control valve which o perat es in throttling mode or actuated valve which intermi ttently operates. 2. Hydraulic Actuator The superiority of h ydraulic actuators is its capabi lity of su pplyi ng very high torques. Since hy draullic is considered as non- compressib le liquid it can provi de fast s troking speed. A typical applic ation of hydraullic actuators is for  wel lhead valv es si nce v ery high torq ues and stro king speed becom e a concer n. 3. Electric Actuator Electric actuator s has smooth operation, provide very high torque values, and retain thrust. In process platform , motor operated va lve is u sed in sea water intake line where large valve which requires high torque is operating in on-off mode. The selec tion of valve actuator type by its power source shall consider several issues as f ollow: Service in process system Mode of operation such as on-off or throttling oper ation. The requirement of valve closing or opening time. Remote valve location For pipeline in the midd le of nowhere, pneumatic actuated valve with s upplementar y air or nitrogen bottle which period ically inspected is th e on ly posibility. Fail-safe requirement Process requirement of valve to fail open, fail close or f ail last. Standard m otor operated valve wi ll be fail last when loosing power supply.  Valv e op erat ing torq ue The actuator torque sh all be larger than the required tor que by valve in specified operati ng process and condition. Safety factor shall be taken into account in selecting the size of the actuator. Insig ht | actuated valv e (SDV/BDV), control valve Home » Insight » Choosing Valve Actuator Power Source instrumentationportal.com  Ins trument and Control Engineeri ng for Process Indus tries INSTRUMENT DOCUMENT | INSTRUMENT DRAWING | INSTRUMENT BASIC KNOWLEDGE INSTRUMENT GLOSSARY  | INSTRUMENT INSIGHT | INSTRUMENT JOB SEEKER Copyright instrumentationportal.com

Choosing Valve Actuator Power Source _ Instrumentationportal

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Home » Insight » Choosing Valve Actuator Power Source

Choosing Valve Actuator Power Source

 Valve Actuator, based on the power source, falls into the three categories. Each power source of valve actuator has

unique characteristic which provide different advantage to make it suitable for specific application.

1. Pneumatic Actuator

Pneumatic actuator is the most commonly used type due to the cheapest price and availability of its power source

 i.e. compressed air. The use of natural gas is also applicable if it is not feasible to install air compressor system. It is

used both for control valve which operates in throttling mode or actuated valve which intermittently operates.

2. Hydraulic Actuator

The superiority of hydraulic actuators is its capability of supplying very high torques. Since hydraullic is considered

as non-compressible liquid it can provide fast stroking speed. A typical application of hydraullic actuators is for

 wellhead valves since very high torques and stroking speed become a concern.

3. Electric Actuator

Electric actuators has smooth operation, provide very high torque values, and retain thrust. In process platform,

motor operated valve is used in sea water intake line where large valve which requires high torque is operating in

on-off mode.

The selection of valve actuator type by its power source shall consider several issues as follow:

Service in process system

Mode of operation such as on-off or throttling operation. The requirement of valve closing or opening time.

Remote valve location

For pipeline in the middle of nowhere, pneumatic actuated valve with supplementary air or nitrogen bottle which

periodically inspected is the only posibility.

Fail-safe requirement

Process requirement of valve to fail open, fail close or fail last. Standard motor operated valve will be fail last when

loosing power supply.

 Valve operating torque

The actuator torque shall be larger than the required torque by valve in specified operating process and condition.

Safety factor shall be taken into account in selecting the size of the actuator.

Insig ht | actuated valve (SDV/BDV), control valve

Home » Insight » Choosing Valve Actuator Power Source

instrumentationportal.com Ins trument and Control Engineering for Process Indus tries

INSTRUMENT DOCUMENT | INSTRUMENT DRAWING | INSTRUMENT BASIC KNOWLEDGE 

INSTRUMENT GLOSSARY  | INSTRUMENT INSIGHT | INSTRUMENT JOB SEEKER 

Copyright instrumentationportal.com