Pipe Size Pressure Flow Calculator

Pipe Size and Flow Rate Formulas:

\[ D = \sqrt{\frac{4 \times Q}{V \times \pi \times 7.481}} \] \[ V = \sqrt{\frac{2 \times (P_1 - P_2) \times 144}{\rho}} \]

Flow Rate (Q):

GPM

Velocity (V):

ft/s

Inlet Pressure (P₁):

psi

Outlet Pressure (P₂):

psi

Density (ρ):

lb/ft³

Pipe Diameter (D): ft

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1. What is a Pipe Size Pressure Flow Calculator?

Definition: This calculator determines pipe diameter and flow velocity based on flow rate, pressure difference, and fluid density.

Purpose: It helps engineers and technicians size pipes and analyze fluid flow in various systems.

2. How Does the Calculator Work?

The calculator uses two fundamental formulas:

\[ D = \sqrt{\frac{4 \times Q}{V \times \pi \times 7.481}} \] \[ V = \sqrt{\frac{2 \times (P_1 - P_2) \times 144}{\rho}} \]

Where:

\( D \) — Pipe diameter (feet)
\( Q \) — Flow rate (gallons per minute)
\( V \) — Flow velocity (feet per second)
\( P_1, P_2 \) — Inlet and outlet pressures (psi)
\( \rho \) — Fluid density (pounds per cubic foot)

Explanation: The first formula calculates pipe diameter from flow rate and velocity, while the second calculates velocity from pressure difference.

3. Importance of Pipe Sizing

Details: Proper pipe sizing ensures efficient flow, minimizes pressure drop, and prevents excessive velocity that can cause erosion or noise.

4. Using the Calculator

Tips: Enter flow rate (GPM), desired velocity (ft/s), pressure values (psi), and fluid density (default 62.4 lb/ft³ for water). All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What's the typical velocity range for water pipes?
A: For water systems, 2-5 ft/s is common for supply lines, 5-10 ft/s for drainage.

Q2: How does pipe material affect the calculation?
A: Material affects friction loss but not these basic calculations. Use more advanced tools for detailed analysis.

Q3: What if I only know the pressure difference?
A: The calculator will determine the resulting flow velocity from the pressure difference.

Q4: Why is density important?
A: Different fluids (oil, water, etc.) have different densities which affect the pressure-velocity relationship.

Q5: Can I use this for gas piping?
A: This calculator is designed for incompressible fluids. Gas calculations require different formulas.