Centrifugal

On low-viscosity media and large flow rates: water, condensate, brines, beer and beverages, milk, cleaning solutions, technical liquids without abrasive. This is the most widespread type of pump in industry thanks to its simple design, high efficiency at the duty point and low maintenance cost.

The duty point is the intersection of the pump curve with the pipeline characteristic: it is precisely there that the pump actually works. If it is displaced from the optimum, the pump loses efficiency, vibrates and overloads the bearings and the seal. That is why the selection is made not "by power", but by the flow-head pair, taking into account the actual losses in the network.

The most frequent cause is cavitation: the pressure at the suction is insufficient, vapour bubbles form in the flow and destroy the impeller. It is remedied by increasing the inlet pressure, by shortening the suction line and increasing its diameter, by lowering the temperature of the product or by selecting a pump with a lower required NPSH.

A mechanical seal has practically no leakage, withstands higher pressures and is mandatory for food, pharmaceutical and chemical applications. Gland packing is cheaper and can be repaired on site, but it allows drip leakage and is not suitable where leakage is unacceptable. For aggressive and toxic media a double mechanical seal with a barrier fluid is used.

Yes, if the flow rate is variable or the network works with throttling. Speed control gives the greatest saving among all measures on a centrifugal pump, reduces water hammer at start-up and extends the service life of the seal. We supply pumps complete with a converter and a control cabinet.