Characteristic curve:
It is the basic function curve of centrifugal pump. Centrifugal pump with less than 80 of the speed of the rise and fall of the characteristics (both intermediate raised, both sides of the lower curve), said the hump function curve. Than the speed of 150 ~ 80 between the centrifugal pump with a flat function curve. Specific speed centrifugal pumps in more than 150 has a steep drop function curve. In general, when the flow of hours, the head is high, with the flow of the added lift will gradually decline.
Flow:
The shaft power is added with the flow, when the flow rate Q=0, the corresponding shaft power is not equal to zero, while for a certain value (about 60% of normal operation). This power is mainly consumed by mechanical loss. At this point is full of water pump, if the long run, will lead to rising the temperature inside the pump, pump casing, bearings may have a fever, severe deformation may pump body heat, which we call "stuffy head", then head for maximum value, when the outlet valve is gradually opened, traffic will gradually add, shaft power also slowly added.
It curves like hill shape, when the flow is zero, the efficiency is equal to zero, with the increase of flow rate, the efficiency gradually add, but to add to the inevitable numerical efficiency of the drop after the efficiency a maximum value, near the maximum efficiency point, the efficiency is relatively high, the region known as the high efficiency area.
