# Water Pressure Loss through Piping

Written by Jerry Ratzlaff on . Posted in Fluid Dynamics

## Water Pressure Loss Through Piping formulas

 $$\large{ p_l = \frac{ \mu \; l \; {v_w}^2 \; \rho \; SG }{ 24 \;d \; g } }$$ $$\large{ p_l = 4.53 \; l \; \frac{ \frac{ Q_w }{ C }^{1.852} }{ d^{4.857} } }$$

### Where:

 Units English Metric $$\large{ p_l }$$ = water pressure loss $$\large{\frac{lbf}{in^2}}$$ $$\large{Pa}$$ $$\large{ \rho }$$  (Greek symbol rho) = density of water $$\large{\frac{lb}{ft^3}}$$ $$\large{\frac{kg}{m^3}}$$ $$\large{ \mu }$$  (Greek symbol mu) = friction coefficient of water $$\large{dimensionless}$$ $$\large{ g }$$ = gravitational acceleration $$\large{\frac{ft}{sec^2}}$$ $$\large{\frac{m}{s^2}}$$ $$\large{ l }$$ = length of pipe $$\large{ft}$$ $$\large{m}$$ $$\large{ C }$$ = pipe coefficient $$\large{dimensionless}$$ $$\large{ d }$$ = pipe inside diameter $$\large{in}$$ $$\large{mm}$$ $$\large{ SG }$$ = specific gravity of water $$\large{dimensionless}$$ $$\large{ Q_w }$$ = water flow rate $$\large{\frac{ft^3}{sec}}$$ $$\large{\frac{m^3}{s}}$$ $$\large{ v_w }$$ = water velocity $$\large{\frac{ft}{sec}}$$ $$\large{\frac{m}{s}}$$