A pressure gauge is an instrument used to measure the pressure of a fluid (liquid or gas) within a system. It is a critical tool in various industries, including manufacturing, automotive, HVAC, and oil and gas, to ensure systems operate safely and efficiently.
Key Components of a Pressure Gauge:
1. Bourdon Tube: The most common sensing element, a curved tube that straightens under pressure, moving the pointer.
2. Diaphragm: Used in low-pressure applications, it flexes under pressure to move the pointer.
3. Pointer: Indicates the pressure reading on the dial.
4. Dial: The face of the gauge, marked with pressure units (e.g., psi, bar, kPa).
5. Case: Protects the internal components and is often made of stainless steel, brass, or plastic.
6. Movement: Converts the mechanical motion of the sensing element into pointer movement.
7. Connection: The threaded or flanged inlet that connects the gauge to the system.
Types of Pressure Gauges:
1. Bourdon Tube Gauge:
- Most common type.
- Suitable for high-pressure applications.
- Works by the expansion of a curved tube under pressure.
2. Diaphragm Gauge:
- Used for low-pressure or corrosive fluids.
- A flexible diaphragm moves in response to pressure changes.
3. Bellows Gauge:
- Used for very low pressures.
- Contains a bellows-like element that expands or contracts.
4. Digital Pressure Gauge:
- Provides a digital readout of pressure.
- Often includes additional features like data logging or alarms.
5. Differential Pressure Gauge:
- Measures the difference in pressure between two points in a system.
6. Absolute Pressure Gauge:
- Measures pressure relative to a perfect vacuum.
