1. What Is PSI To PSIG Conversion?

PSI to PSIG conversion calculates gauge pressure from absolute pressure by subtracting atmospheric pressure. PSI (absolute) includes atmospheric pressure, while PSIG (gauge) measures pressure relative to atmospheric pressure.

2. How Does The Calculator Work?

The calculator uses the PSIG conversion formula:

Where:

• \( PSI_{absolute} \) — Absolute pressure in pounds per square inch
• \( 14.7 \) — Standard atmospheric pressure at sea level (psi)
• \( PSIG \) — Gauge pressure in pounds per square inch gauge

Explanation: This conversion accounts for the atmospheric pressure that is always present, allowing measurement of pressure relative to ambient conditions.

3. Importance Of Pressure Conversion

Details: Accurate pressure conversion is essential for engineering applications, industrial processes, HVAC systems, and safety monitoring where gauge pressure readings are standard.

4. Using The Calculator

Tips: Enter absolute pressure in PSI. The calculator will automatically subtract atmospheric pressure (14.7 psi) to provide the gauge pressure in PSIG.

5. Frequently Asked Questions (FAQ)

Q1: What is the difference between PSI and PSIG?
A: PSI refers to absolute pressure (including atmospheric pressure), while PSIG is gauge pressure (excluding atmospheric pressure).

Q2: Why subtract 14.7 psi?
A: 14.7 psi represents standard atmospheric pressure at sea level, which must be subtracted to get gauge pressure relative to ambient conditions.

Q3: Does atmospheric pressure change with altitude?
A: Yes, atmospheric pressure decreases with altitude. 14.7 psi is standard for sea level; adjustments may be needed for high-altitude locations.

Q4: When is PSIG used vs PSIA?
A: PSIG is commonly used for most pressure gauges and industrial applications, while PSIA is used in scientific calculations and vacuum systems.

Q5: Can PSIG be negative?
A: Yes, when absolute pressure is less than atmospheric pressure, PSIG becomes negative, indicating vacuum or suction conditions.