Tank Volume Calculator Gallons Per Inch

GPI Formula:

\[ GPI = \frac{\pi (D/2)^2}{231} \]

Gallons Per Inch (GPI):

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1. What is Gallons Per Inch (GPI)?

Gallons Per Inch (GPI) is a measurement used to determine the volume of liquid in a cylindrical tank per inch of depth. It's particularly useful for tank calibration and inventory management in various industries.

2. How Does the Calculator Work?

The calculator uses the GPI formula:

\[ GPI = \frac{\pi (D/2)^2}{231} \]

Where:

\( GPI \) — Gallons per inch (gal/in)
\( D \) — Tank diameter (inches)
\( \pi \) — Mathematical constant (approximately 3.1416)
231 — Conversion factor (cubic inches to gallons)

Explanation: The formula calculates the cross-sectional area of the tank, then converts it to gallons per inch of depth using the standard conversion factor of 231 cubic inches per gallon.

3. Importance of GPI Calculation

Details: Accurate GPI calculation is essential for inventory management, fuel storage monitoring, chemical processing, and any application where precise liquid volume measurement in cylindrical tanks is required.

4. Using the Calculator

Tips: Enter the tank diameter in inches. The value must be greater than zero. The calculator will compute the gallons contained per inch of liquid depth in the tank.

5. Frequently Asked Questions (FAQ)

Q1: Why is 231 used in the formula?
A: 231 is the conversion factor from cubic inches to US gallons (1 US gallon = 231 cubic inches).

Q2: Does this work for tanks of any shape?
A: No, this formula is specifically for cylindrical tanks with a circular cross-section. Other tank shapes require different formulas.

Q3: Can I use this for metric measurements?
A: This calculator uses imperial units. For metric, you would need to convert measurements or use a different formula with liters and centimeters.

Q4: How accurate is this calculation?
A: The calculation is mathematically precise for perfect cylinders. Actual tanks may have variations due to construction, so physical calibration may be needed for critical applications.

Q5: What if my tank isn't completely cylindrical?
A: For tanks with different shapes (elliptical, rectangular, etc.), specialized formulas are required that account for the specific geometry.