Pipes and Fluid Flow Velocities

Calculate fluid flow and pipe velocities in pipes and tubes

Imperial units

Fluid flow velocity in a circular pipe can be calculated with Imperial or American units as

v = 1.273 q / d2

= 0.4084 qgpm / din2         (1)

where

v = velocity (ft/s)

q = volume flow (ft3/s)

d = pipe inside diameter (ft)

qgpm = volume flow (US gal./min)

din = pipe inside diameter (inches)

SI units

Fluid flow velocity in a circular pipe can be calculated with SI units as

v = 1.273 q / d2         (2)

where

v = velocity (m/s)

q = volume flow (m3/s)

d = pipe inside diameter (m)

Example - Flow Velocity in a Steel Pipe

60 US gal/min is flowing through a 4 inch schedule 80 steel pipe. The internal diameter of the pipe is 3.83 in. The velocity can be calculated as

v = 0.4085 (60 gal/min) / (3.83 in)2   

   = 1.7 ft/s

Related Topics

  • Fluid Mechanics - The study of fluids - liquids and gases. Involves various properties of the fluid, such as velocity, pressure, density and temperature, as functions of space and time.
  • Fluid Flow and Pressure Drop - Pipe lines - fluid flow and pressure loss - water, sewer, steel pipes, pvc pipes, copper tubes and more
  • Pipe Sizing - Sizing steam and condensate pipes - pressure loss, recommended velocity, capacity and more

Related Documents

Tag Search

  • en: flow velocity pipes american units
  • es: tuberías de velocidad de flujo unidades estadounidenses
  • de: Strömungsgeschwindigkeit Rohre amerikanischen Einheiten

Search the Engineering ToolBox

- "Search is the most efficient way to navigate the Engineering ToolBox!"

Engineering ToolBox - SketchUp Extension - Online 3D modeling!

3D Engineering ToolBox Extension to SketchUp - add parametric components to your SketchUp model

Add standard and customized parametric components - like flange beams, lumbers, piping, stairs and more - to your SketchUp model with the Engineering ToolBox - SketchUp Extension/Plugin - enabled for use with the amazing, fun and free SketchUp Make and SketchUp Pro . Add the Engineering ToolBox extension to your SketchUp from the Sketchup Extension Warehouse!

Translate the Engineering ToolBox!
About the Engineering ToolBox!

Support the ToolBox

If you find the Engineering ToolBox useful and want this website to be available tomorrow - and the days after tomorrow - enable ads or make a contribution!

Contribute to the Engineering ToolBox

close