New open impeller single stage ESH pump
Ceramic bearing is shaft sealing

The ESH range of horizontal centrifugal pumps, is a new generation of pumps, especially designed for the handling of sludge and pulp.

One of the outstanding charac- teristics of this pump is without any doubt the shaft sealing. By application of a ceramic bearing, especially designed for that purpose, a unique combination of bearing and shaft sealing has been realized (long life seal - bearing bracket).

Special features
- The pump has an open impeller with a large grain size. The impeller is appropriate to consistencies of paper-pulp up to 10 % atro without decrease of the efficiency and also allows air inclusions till 6 volume %. An adapted construction can transport up to 15 % gas volume.
- Renewable wear plates are protecting the casing against erosive parts in the liquid.
- A robust bearing bracket also holds the shaft sealing. The compact construction allows long working life.

Ceramic bearing
The ceramic bearing – which has been mounted flexibly – is situated immediately behind the impeller, so that the so called "overhang" of the impeller has been reduced to a minimum. The insensibility for cavitation results in a combination bearing/shaft sealing, excellently appropriate to constructions under vacuum. At the coupling side there is a robust grease-lubricated angular contact bearing mounted in O-position in order to reduce the axial forces. The angular contact bearing is protected by lip ring seals. Outside there is also a labyrinth sealing in order to prevent the penetration of water or any other liquid. The bearing bracket is completely closed and is provided with a connection for pure flushing medium. The flushing medium, which is supplied with a differential pressure of ca. 2 bar up on the pressure behind the impeller, has to lubricate and clean the ceramic bearing. The maximum flushing pressure comes to 12 bar. Depending on the size of the bearing bracket, the consumption of the flushing medium only ranges from 3 to 10 litre per hour. So, an inadmissible thinning of the medium belongs to the past. In order to avoid leakage of the flushing medium, a standard mechanical seal will be mounted. This seal doesn’t get into touch with the pumped liquid.

Worldwide licence
A licence, which will be valid worldwide, has been asked for the unique construction of the ceramic bearing with shaft sealing. By using a flushing medium which is completely pure, we can guarantee that the pumps operate without any leakages under all imaginable circumstances during a period of 2 years continuous working.