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Flow in pressurized pipe

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Flow in pressurized pipe diagram
The pressure form of the Hazen-Williams equation is evaluated to provide the pressure loss per unit length and over the entire length of a pipe. Convenient (metric, imperial, US) units may be chosen from the menus.
Pipe diameter:
Pipe length:
Discharge rate:
Roughness coefficient:

Water velocity:
Pressure loss
Total pressure loss:
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The Hazen-Williams formula is an empirical rule, that holds well for cold water running in pipes under turbulent flow conditions. This is very suitable for situations such as domestic piping and hosing, sprinkler and irrigation systems, etc. For gravitational flow, and for open-channel flow, other calcs are available.
Typical values of the roughness (friction loss) coefficient include: 100 (concrete, cast iron); 120 (steel); 140 (cement); 150 (copper, plastics).