Pipe Fill Volume
Find the volume and fill time of a length of pipe.
About Pipe Fill Volume
A pipe's water volume is its cylindrical interior. Multiplying cubic feet by the gallons per cubic foot gives the capacity, and dividing by the fill rate gives the time. Knowing the fill volume matters for purging, testing and sizing water in long pipe runs.
Formula
Pipe Fill Volume
Gallons = pi x radius^2 x length x 7.48; time = gallons / rate
- fill rate
- Gallons per minute being pumped in
Worked example
With the default values below, Pipe Fill Volume returns Volume Gallons of 18.4. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Pipe length
- 50 ft
- Inside diameterminimum 0.1 in
- 3 in
- Number of runsminimum 1
- 1
- Fill rateminimum 0.1 gpm
- 10 gpm
Results
- Volume
- 2.45 cu ft
- Volume Gallons
- 18.4 gal
- Fill Time
- 2m
Step by step
- 1Values used
- 2Pipe Fill Volume
- 3Volume Gallons= 18.4 gal
- 4Volume= 2.45 cu ft
- 5Fill Time= 1.84
Assumptions and limits
- The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is Pipe Fill Volume calculated?
Gallons = pi x radius^2 x length x 7.48; time = gallons / rate A pipe's water volume is its cylindrical interior. Multiplying cubic feet by the gallons per cubic foot gives the capacity, and dividing by the fill rate gives the time.
Why does Pipe Fill Volume matter?
Knowing the fill volume matters for purging, testing and sizing water in long pipe runs.
What values do I need to enter?
This calculator takes 4 inputs: Pipe length, Inside diameter, Number of runs, Fill rate. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.