imp gpm

imperial gallon per minute

Volumetric flow rateexact by definition

The imperial gallon per minute is exactly 4.54609 × 10⁻³/60 cubic metres per second, about 0.0758 L/s. It is the flow unit of older British and Commonwealth pump and pipework practice, and it still appears on legacy UK plant documentation.

Watch out: An imperial gallon is 20 percent larger than a US gallon, so 100 imp gpm is 120 US gpm. British pump curves imported into North American calculations without the conversion undersize everything downstream by a fifth.

1 imp gpm 4.54609 L/min