Volume Booster: Function, Operation & Application

Function of a Volume Booster

A volume booster is a device that amplifies or boosts the volume of air supplied to the actuator, that is, it takes an input signal and produces an output of a large volume flow of air to the actuator; to be precise, a volume booster is a pneumatic device made in such a way to reproduce a pneumatic pressure signal (1:1 ratio), however with far greater output flow capacity; in brief, we can thus say that a volume booster is device used to source and vent compressed air for the valve actuator. The figure below illustrates a volume booster:

Operation of a Volume Booster

Consider the internal construction of a volume booster below:

With reference to the figure above, an internal diaphragm senses output pressure and acts against a force (a spring preloaded by an external pressure acting on another diaphragm) to position an air flow throttling/venting mechanism. If the output pressure is less than desired, the diaphragm moves down to open the air sourcing plug and supply additional air volume to the output. If the output pressure is greater than desired, the diaphragm moves up to shutoff the sourcing plug and open the venting port to relieve air pressure to the atmosphere.

Application of a Volume Booster

Volume booster is used to enhance the pneumatic control valve response (reduces time lag) by increasing the air flow rate. A typical application equipped with a volume a booster is demonstrated below:

Related articles:

• Valve Positioners: Function & Types
• The Parts and Functions of a Valve
• Pressure Control Valve Operation
• Electro-Pneumatic Valve Positioners: Function & Features
• Pneumatic Actuators
• Pressure Regulators: Function & Types
• Selecting a Pressure Reducing Regulator: Key Parameters to Consider