What is the effect of the medium’s temperature on the suction lift of a self-priming pump?
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When using a self-priming pump to draw hot water, does the water temperature affect the pumping height? Some pump manufacturers say that the pumps can’t draw fluid when the temperature exceeds a certain level, is that true?
This issue can only be addressed after the manufacturer makes a decision; it’s necessary to know what exactly that \"certain high level\" is, so as to avoid problems down the road. This high temperature is higher than the saturation temperature at which cavitation can occur, and the pressure corresponding to this saturation temperature can be adjusted by reducing the suction lift, which in turn means increasing the liquid level. The manufacturer of the pump still needs to provide the relevant data. Or produce special equipment according to the usage conditions you specified. Factors such as the pump’s net positive suction head and suction lift relate to pressure, while saturated temperature is associated with them. For reference.
The temperature of water affects the suction lift; as the temperature rises, the saturated vapor pressure increases, and the allowable suction vacuum level for self-priming pumps decreases. Generally not higher than 80 degrees
Hot water at temperatures above 80 degrees is very difficult to draw up using a self-priming pump. The principle behind this is simple: as explained in junior high school physics, the boiling point of water decreases as pressure drops. When trying to draw liquid up, the pressure at the surface of the liquid is lower than atmospheric pressure; this lower boiling point causes the liquid to vaporize rapidly, and what is drawn up is actually water vapor. Then it experienced flutter. For our vertical self-priming pumps, we always ask the customer about the temperature of the medium; they are not recommended for use when the temperature exceeds 80 degrees. It is recommended to switch to a submersible pump.
The higher the temperature, the easier it is for the fluid to vaporize, and the gases within the fluid are also more likely to separate out, making cavitation more likely to occur
The higher the temperature, the easier it is to vaporize under negative pressure; once gas is produced, it can no longer be drawn out