Could the experts recommend a pump with a low net positive suction head? Thank you!
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I need a pump with a low net positive suction head requirement – an axial flow pump or a centrifugal pump – with a flow rate of 30 m3/h, a head of 3 m, and a net positive suction head of less than 1.5 m. Please recommend some options, thanks!
With such a low net positive suction head, neither of these two pumps will be able to meet it. I’m wondering why you need such a low net positive suction head under your operating conditions
I’m quite troubled because a small crystallization skid-mounted testing setup needs to be designed, and its height is limited
Where do you calculate that the net positive suction head should be less than 1.5M?
The backflow feeding issue should be easy to resolve; you can refer to the following measures. Measures to prevent cavitation: To avoid cavitation, it is necessary to increase NPSHa so that NPSHa > NPSHr. The measures to prevent cavitation are as follows: a) Reduce the geometric suction head hg (or increase the geometric backflow height)； b. Reduce the suction loss hc; this can be achieved by increasing the pipe diameter, minimizing the length of the pipelines, as well as reducing the use of elbows and other fittings ； c. Prevent operation at high flow rates for extended periods of time ； d. At the same speed and flow rate, a double-suction pump is used, as it reduces the inlet flow velocity and thus makes cavitation less likely to occur ； e. When cavitation occurs in the pump, the flow rate should be reduced or the pump should operate at a lower speed ； f. The conditions of the pump suction tank have a significant impact on pump cavitation ； g. For pumps operating under harsh conditions, to avoid cavitation damage, cavitation-resistant materials can be used.
Using a low-speed centrifugal pump can achieve levels below 1.5 meters! No problem at all. I checked the company’s information!
Hello! I checked the data for low-speed centrifugal pumps (1450 rpm), and the NPSH value is also around 2.5 meters
It’s better to raise the tank height; the required net positive suction head for the pump is generally around 2 meters, so there’s no need to make things too complicated
It’s just that there’s a height limit; otherwise, there wouldn’t be such a dilemma.:)