NPSH is the abbreviation of Net Positive Suction Head, literally translated as net positive suction head, our country is commonly referred to as cavitation allowance, which refers to the impeller inlet (relative to the reference plane) liquid has more than the liquid vapor pressure at this temperature energy. It is determined by the pump installation conditions. The head of the form. The unit is m. The required (NPSH) value for a given pump at a given speed and flow is given at design time and is called the required NPSH r in m. At a given flow rate or lift, the NPSH value of the first stage impeller just called cavitation, known as the critical NPSH, in m.
