Home
Back
Pressure Conversion Formula:
| From: | To: |
Absolute pressure is the total pressure measured relative to a perfect vacuum (zero pressure), while gauge pressure is the pressure measured relative to atmospheric pressure. The relationship between them is defined by the formula: Absolute = Gauge + Atmospheric Pressure.
The calculator uses the pressure conversion formula:
Where:
Explanation: This formula converts gauge pressure readings to absolute pressure by adding the standard atmospheric pressure value.
Details: Understanding the difference between absolute and gauge pressure is crucial in various engineering applications, including HVAC systems, pneumatic controls, and pressure vessel design. Accurate pressure conversion ensures proper system operation and safety.
Tips: Enter the gauge pressure value in psig (pounds per square inch gauge). The calculator will automatically compute the corresponding absolute pressure in psia (pounds per square inch absolute).
Q1: Why is atmospheric pressure 14.7 psi?
A: 14.7 psi is the standard atmospheric pressure at sea level. This value represents the average pressure exerted by Earth's atmosphere at sea level conditions.
Q2: Does atmospheric pressure change with altitude?
A: Yes, atmospheric pressure decreases with increasing altitude. The 14.7 psi value is standard for sea level calculations.
Q3: When should I use absolute pressure vs gauge pressure?
A: Use absolute pressure for scientific calculations and thermodynamic equations. Use gauge pressure for most industrial and mechanical applications where pressure relative to atmosphere is sufficient.
Q4: What is the difference between psia and psig?
A: PSIA refers to pounds per square inch absolute (relative to vacuum), while PSIG refers to pounds per square inch gauge (relative to atmospheric pressure).
Q5: Can this calculator be used for negative gauge pressures?
A: Yes, the calculator works for both positive and negative gauge pressure values, converting them to the corresponding absolute pressure values.