Piping Pressure Drop Calculator

Pressure Drop Formula:

\[ \Delta P = \frac{f \times L \times \rho \times V^2}{2 \times D \times 144} \]

Friction Factor (f):

dimensionless

Pipe Length (L):

Fluid Density (ρ):

lb/ft³

Flow Velocity (V):

ft/s

Pipe Diameter (D):

Pressure Drop (ΔP):

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is a Piping Pressure Drop Calculator?

Definition: This calculator estimates the pressure loss (psi) in piping systems due to friction using the Darcy-Weisbach equation.

Purpose: It helps engineers and designers determine the pressure loss in pipes to ensure proper system performance and pump sizing.

2. How Does the Calculator Work?

The calculator uses the Darcy-Weisbach equation:

\[ \Delta P = \frac{f \times L \times \rho \times V^2}{2 \times D \times 144} \]

Where:

\( \Delta P \) — Pressure drop (psi)
\( f \) — Darcy friction factor (dimensionless)
\( L \) — Pipe length (ft)
\( \rho \) — Fluid density (lb/ft³)
\( V \) — Flow velocity (ft/s)
\( D \) — Pipe diameter (ft)

Explanation: The equation calculates the pressure loss due to friction between the fluid and pipe walls, converting the result to psi.

3. Importance of Pressure Drop Calculation

Details: Accurate pressure drop calculations are essential for proper pump selection, energy efficiency, and ensuring adequate flow rates throughout the system.

4. Using the Calculator

Tips: Enter the friction factor (default 0.02 for turbulent flow), pipe length, fluid density (default 62.4 lb/ft³ for water), flow velocity, and pipe diameter. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: How do I determine the friction factor?
A: For turbulent flow, use Moody chart or Colebrook equation. For laminar flow (Re < 2000), f = 64/Re.

Q2: What's a typical fluid density for water?
A: Water at 60°F is approximately 62.4 lb/ft³. Density varies with temperature and composition.

Q3: How does pipe diameter affect pressure drop?
A: Pressure drop is inversely proportional to pipe diameter - smaller pipes create significantly higher pressure losses.

Q4: What velocity is recommended for water pipes?
A: Typically 2-8 ft/s for water, with 4-6 ft/s being common for balance of pressure loss and pipe size.

Q5: Does this include fittings and valves?
A: No, this calculates straight pipe losses only. Use equivalent length method for fittings.