Pounds per hour measures the flow of fluids in terms of mass, and it is useful for describing a process's total production rate. Gallons per minute measures the flow of fluids in terms of volume, so it can accurately describe the transport of a fluid through a pipe. If you know a fluid's density, you can convert its PPH to GPM by performing three simple calculations.

Divide the flow rate in PPH by the fluid's density. For example, if 10,000 pounds flow each hour and the fluid has a density of 62 pounds per cubic foot, 10,000 / 62 = 161.3 cubic feet per hour.

Divide the cubic feet per hour by 0.1337 to convert them to gallons per hour. For example, 161.3 / 0.1337 = 1,206.4 gallons per hour.

Divide the gallons per hour by 60 to convert them to gallons per minute. For example, 1,206.4 / 60 = 20.1 gallons per minute.
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