Working Principle

The most common measurement principle is mechanical, primarily utilizing the Bourdon tube. 

• Bourdon Tube: A curved, flattened metal tube that tends to straighten as internal pressure increases.
• Mechanical Linkage: As the tube straightens, it moves a gear and lever system.
• Visual Output: This motion drives a needle across a calibrated dial to show the reading.
• Electronic Measurement: Digital gauges use piezoelectric or strain gauge sensors to convert pressure into electrical signals, which are then shown on an LCD.