Oval Gear type flowmeter

                                                             These are positive displacement flowmeters. These divide the fluid in measured portion and then pump it.

In oval gear type flow meters, two oval shaped synchronized gears are fixed such that their teeth are in perfect contact. As the shaft moves, a specific amount of fluid gets trapped between gears and the casing of the meter and is pumped with every stroke of the gears.

This ensures that only a fixed amount of fluid is pumped in each stroke. The flow can be calculated by multiplying the volume contained in each stroke by number of strokes (which can be counted by monitoring shaft rotations).

The other types implement different mechanisms such as reciprocating pistons, mutating disc etc. but the basic principle of measurement remains the same.

The flow can be calculated by multiplying the number of strokes with volume of fluid pumped in each stroke. These flowmeters are accurate and deliver precise quantities of fluid.