The relationship between medium density, power, and head
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How many users think that a higher medium density requires an increased head? Case 1: The medium density is 1700 kg/m3, and the actual head required on-site is only around 30 meters; yet due to the high density of the medium, the head specified to the supplier is 60 meters? This is a wrong concept; how should a pump be used? Case 2: The medium density is 1700 kg/m3; the actual head required on-site is around 30 meters, and the head specified to the supplier is also around 30 meters. The motor power is increased appropriately based on the density. This is the right one
For liquid pumps, the density of the fluid does not directly affect the head, but it does influence the power requirement of the pump. This is because the power requirement of the pump depends on the weight of the fluid, and the weight of the fluid depends on its density and volume. Therefore, for liquids of the same volume, those with a higher density require more power to be pumped. The approach in Case 1 is incorrect. Head is the maximum height that a pump can lift a fluid to, and it is independent of the density of the medium. If the actual head required is only 30 meters, but the head specified to the supplier is 60 meters, this may mean that the pump’s performance has been over-designed, which can lead to energy waste and a reduced lifespan of the equipment. The approach in Case 2 is correct. If the actual required head is 30 meters, this head requirement should be provided to the supplier. As for the motor power, it needs to be increased appropriately depending on the density of the liquid. Because liquids with higher density require more power to be pumped. Generally speaking, the key factors in selecting a pump should be the actual head and flow rate requirements, as well as the density of the medium. This information will determine the type and size of the pump as well as the power of the motor. .
This situation is extremely common; there is no inherent relationship between head and specific gravity, while specific gravity is directly proportional to power
The outlet pressure is related to density, while the head has nothing to do with density