How is total GPM flow calculated when multiple lines supply a single flow or pump?

The process of calculating total GPM (gallons per minute) flow when multiple lines supply a single flow or pump involves understanding how flows from different sources combine. When multiple supply lines are used, the total flow rate cannot simply be summed up or multiplied because each line may contribute differently to the overall flow.

In a system where multiple lines are supplying water to a single pump or outlet, the overall flow rate may be affected by the individual contributions of each line and their respective pressures and resistance. When combining flows from different sources, it’s essential to consider how these flows interact and the overall system dynamics.

By dividing the total GPM flow, you account for the shared pressure and dynamics between the lines, providing a more accurate representation of the system's overall capability under varied conditions. This method reflects the actual availability of flow based on the system's configuration and prevents overestimation of the total flow, which could lead to operational issues.

The reasoning behind not simply summing or multiplying the flows helps ensure safe and effective operations when managing multiple supply lines.