Psi To Psig Conversion Calculator

PSIG Conversion Formula:

\[ PSIG = PSI - 14.7 \]

Gauge Pressure (PSIG):

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1. What is PSI to PSIG Conversion?

PSI to PSIG conversion calculates gauge pressure from absolute pressure by subtracting atmospheric pressure (14.7 psi). PSI (pounds per square inch absolute) includes atmospheric pressure, while PSIG (pounds per square inch gauge) measures pressure relative to atmospheric pressure.

2. How Does the Calculator Work?

The calculator uses the PSIG conversion formula:

\[ PSIG = PSI - 14.7 \]

Where:

\( PSI \) — Absolute pressure in pounds per square inch
\( 14.7 \) — Standard atmospheric pressure at sea level in psi
\( PSIG \) — Gauge pressure in pounds per square inch gauge

Explanation: This conversion accounts for the fact that gauge pressure readings are typically zero-referenced to atmospheric pressure, while absolute pressure includes the atmospheric component.

3. Importance of Pressure Conversion

Details: Accurate pressure conversion is crucial for engineering applications, industrial processes, pneumatic systems, and pressure vessel design where gauge pressure measurements are standard.

4. Using the Calculator

Tips: Enter absolute pressure (PSI) in pounds per square inch. The value must be greater than 0. For accurate results, ensure your input represents absolute pressure rather than gauge pressure.

5. Frequently Asked Questions (FAQ)

Q1: What is the difference between PSI and PSIG?
A: PSI refers to absolute pressure (includes atmospheric pressure), while PSIG refers to gauge pressure (relative to atmospheric pressure). PSIG = PSI - 14.7.

Q2: Why is atmospheric pressure 14.7 psi?
A: 14.7 psi is the standard atmospheric pressure at sea level. This value can vary slightly with altitude and weather conditions.

Q3: When should I use PSIG vs PSI?
A: Use PSIG for most industrial and mechanical applications (tire pressure, hydraulic systems). Use PSI (absolute) for scientific calculations and vacuum measurements.

Q4: Can PSIG be negative?
A: Yes, PSIG can be negative when measuring vacuum or pressures below atmospheric pressure.

Q5: How does altitude affect this conversion?
A: At higher altitudes, atmospheric pressure decreases. For precise calculations at high elevations, use the local atmospheric pressure instead of 14.7 psi.