Water Headloss Calculator




    The Hazen–Williams equation is an empirical formula which calculates pressure drop of water in circular pipes caused by friction. It is used in the design of water pipe systems such as fire sprinkler systems, water supply networks, and irrigation systems.

    The Hazen–Williams equation has the advantage that the coefficient C is not a function of the Reynolds number, but it has the disadvantage that it is only valid for water.
    Input parameters are flow, pipe diameter, lenght of pipe and C is a roughness coefficient, known as William Hazens coefficient, with values ​​between 90 (more rough pipes) and 140 (smooth pipes, ex PVC).

    You can select between imperial (U.S. customary units) and metric unit (International System of Units).

    If you want to take into account the pressure loss in fittings and valves, and the selection coefficient C for each material, then find our version of the application pro at

    Tags: head loss calculator metric , water head loss calculator , calculate headloss , pipe head loss calculator metric , hazen williams calculator metric , formule perte de charge pompier , perdidas locales en tuberías , programa para calcular perdidas de carga , pertes de charges coefficient de hazen_williams

    Users review

    from 124 reviews