The installation height of the centrifugal pump depends on whether cavitation occurs in the centrifugal pump, and the cavitation of the centrifugal pump is closely related to the vaporization of the liquid being transported. Therefore, a special case of the vaporization of the liquid should be studied—boiling. And the pressure on the liquid surface when the liquid boils - the saturated vapor pressure.
How does centrifugal pump cavitation happen: It can be found in daily life that when water is heated to 100'C, the water boils and turns into water vapor and emits into the atmosphere. As the altitude increases, the temperature at which the water boils decreases. This is because as the altitude increases, the air gradually becomes thinner, the concentration of air molecules on the water surface decreases, and the atmospheric pressure also decreases, and the pressure formed by the water molecules escaping from the water is closer to the atmospheric pressure. When the pressure of water vapor is equal to atmospheric pressure, water boils, so when a liquid boils at a certain temperature, the pressure above the liquid surface is called the saturated vapor pressure of the liquid at that temperature.
It should be clear that various liquids have different vaporization rates, boiling temperatures and pressures due to their different properties, and therefore their saturated vapor pressures are also different.