Centrifugal Pumps

Five Important Variables for The Selection of Centrifugal Pump

Centrifugal pumps are one of the most widely used rotatory machines in the industry. Selection of the correct centrifugal pump for your required application is an important task. Often, customers are confused when it comes to selecting a right centrifugal pump.

Centrifugal Pump

Do you know the key criteria to consider while choosing a centrifugal pump? No! Find them below.

The top five factors to consider while choosing a right centrifugal pump:

1. Materials of Construction (MOC)

Since your pump is going to be in direct contact with the fluid, the construction material should be chosen accordingly. Otherwise, the fluid would harm and corrode the parts. And, soon your pump would be junk.

2. Flow rate

You should have clear data of flow rate (volume per unit time) needed. Once you know the flow rate, you can choose the right pump size depending on the viscosity of fluid. Other factors that affect flow rate are a static lift, friction losses and differential pressure in the line.

3. Net Positive Suction Head (NPSH)

NPSH is the difference between the fluid pressure at pump suction and fluid vapour pressure. It is denoted in terms of height of the liquid column. NPSHr, the required NPSH of a pump is specified by the manufacturer, while you have to calculate the available NPSHa. As a rule of thumb, the required NPSHr of a pump should always be lower than the available NPSHa of the system. Else, there would be an issue of cavitation.

4. fluid Properties And External Environment

External environment decides the metallurgy of your pump? Are you going to employ pump in minus temperature condition? Or is it going to be used in too hot surrounding? You would require cryogenic metallurgy for a low-temperature condition. Similarly, for hazardous condition ‘fire safe tested’ pumps are required.

Just as the external condition is important, the complete specifications of the fluid in line should be clear to you.

5. Important features of fluid to consider are:

  • Viscosity
  • Temperature
  • Density
  • Vapour pressure
  • Nature of fluid: Whether Abrasive or Non-abrasive? Or whether it is acidic, basic or neutral?

With all these points in mind, you can select right centrifugal pumps for any application without any confusions.