Hydraulics

As a result of the Turo® System, the major proportion (85%) of the fluid being pumped is transported directly from the primary vortex to the pressure connection. Only 15% of the fluid being pumped comes in contact with the impeller through the secondary vortex. Sealing gaps which could wear during solids handling and cause grinding effects are not present in our construction. That reduces the abrasive attack to a minimum and sensitive structures in the material to be conveyed such as crystals, bacterial flakes or algae remain largely unaffected. Any potential wear on the impeller always develops symmetrically; therefore the balance and thus the quiet running of the pump remain assured. The output will only drop significantly with an almost completely abraded impeller.

One component of the Turo® System is the patented axial volute in the casing. In other words, Egger specially applies coordinated casing geometries to the vortex impeller. This optimal interaction between impeller and casing confers to Egger Turo®-Pumps the high discharge heads and efficiency uniquely achievable by vortex impeller pumps. Because of their insensitivity to wear, efficiency levels are sustained, even over long periods of time.

This feature is achieved by the com- pletely recessed impeller. Solid objects up to the diameter of the pressure outlet and long fibrous materials do not cause any malfunctions. There are no channels that the solids have to pass through nor are there any radial gaps between the pressure and suctions sides that could be clogged by fibers and otherwise obstruct the pump.

Ordinary radial impellers are known for their limited transport of gas content which results in a drastic reduction of output to the point where delivery stops altogether. Since its founding in 1947, Egger has focussed on this problem. Our special blade geometry guarantees the delivery of gas contents up to 25%, as has been proven in numerous reactor loop installations in the chemical industry. This hydraulic family exhibits low NPSHR values.

Semi-open impellers have a fixed wear plate opposite them. The gap between them is critical for the perfor- mance data (Q, H, η). For abrasive fluids, the gap gets bigger and bigger and causes a reduction in the nominal pump values. The pumps in the EO and EOS families are equipped with a wear plate that can be adjusted from the outside and with which one can reset the impeller gap back to its original size. Thus, the specified original delivery characteristic values can be restored and a replacement can be usually omitted in the longer term. As an alternative, under con- ditions of high wear, the casing cover can also be equipped with a replace- able wear insert.