Mass rate of flow

The mass of liquid discharged from the outlet area of the pump in a given time. Losses inherent to the pump i.e. discharge necessary for

• the hydraulic balancing of axial thrust,
• cooling of bearings of the pump,
• liquid seal to the packing,
• leakage from fittings, internal leakage, etc.

should not to be reckoned in the mass rate of flow. Quantities used for other purposes, such as:

• cooling of motor bearings,
• cooling of gearbox (bearings, oil cooler) etc.

should be reckoned in the mass rate of flow, if they are taken from a point before the flow measuring section. Whether and how these flows should be taken into account depends upon the location of their source and relationship to the flow-measuring section. Symbol: q Unit: kg/h, kg/s, t/h