Pipe Flow Calculator

Calculate flow rate, velocity, and Reynolds number for petroleum pipelines

Flow Parameters

Enter pipe and fluid properties

Fluid Properties
Water = 1.0, Light crude ~0.85
Water ~1 cP, Crude oil 5-50 cP
Pipe Properties (for pressure drop)

Flow Results

Enter parameters and click Calculate

Recommended Velocities

  • Suction lines: 2-4 ft/s
  • Discharge lines: 6-10 ft/s
  • Crude oil pipelines: 3-8 ft/s
  • Products pipelines: 5-12 ft/s

Formula Reference

Flow Velocity

V = Q / A = 0.4085 x Q / d^2 Where: V = velocity (ft/s) Q = flow rate (GPM) d = pipe ID (inches) A = cross-sectional area

Reynolds Number

Re = (7742 x Q x SG) / (d x mu) Or: Re = (928 x d x V x rho) / mu Where: Q = flow rate (GPM) SG = specific gravity d = pipe ID (inches) mu = dynamic viscosity (cP) V = velocity (ft/s) rho = density (lb/ft3)

Flow Regime Classification

  • Laminar: Re < 2,300
  • Transitional: 2,300 < Re < 4,000
  • Turbulent: Re > 4,000

Darcy-Weisbach Pressure Drop

dP = f x (L/D) x (rho x V^2 / 2) Friction factor (f) from Colebrook equation for turbulent flow: 1/sqrt(f) = -2 log10((e/D)/3.7 + 2.51/(Re x sqrt(f))) Where: dP = pressure drop f = Darcy friction factor L = pipe length D = pipe diameter e = pipe roughness