Pump technology

Industrial focus on innovative pump technology. Production of pumps and the solution to hydraulic requirements is a core corporate competence. Egger is the industry leader in the area of difficult liquids and liquids with a tendency to clog.

Since its founding in 1947, the enterprise has focussed on the integrated manufacturer of pumps. This specialization has led to great depth of experience – on the one hand, in the production of pumps with all of their components and on the other, in mastering the many requirements made available by a wide assortment of pumps in a large variety of industries. Both management and staff are technical experts in pump technology. Knowledge of materials, hydraulic expertise and experience in the execution of processes make Egger a sought-after consultant when it comes to the pumping of fluids.

Principle of the centrifugal pump

A centrifugal pump is a continuous flow machine with a rotating impeller within its pump casing. The fluid enters via an intake manifold and is forced into rotation by the impeller. As a result, the liquid is driven in a circular path toward the outside. The kinetic energy thus developed is converted into pressure energy in the discharge area of the casing and forced into the discharge pipe. The pumped fluid in a centrifugal pump is directed either transversely from the drive axle (radial flow) or in the direction of the drive axle (axial flow).

Radial flow pump (T – EO / EOS – TEO)

Radial pumps are centrifugal pumps for which the liquid being pumped exits from the impeller radially, in other words, perpendicular to the pump shaft. As a result of this deflection of the flow in the impeller, higher centrifugal forces result than in axial machines; this results in higher supply pressures but lower flowrates.


Efficient back vanes: Pressure relief of the shaft seal and axial thrust compensation

Every centrifugal pump has a shaft seal in the rear portion of the pump casing. It is precisely for liquids containing particles and gas that the seal becomes such an important component of the pump and therefore of special importance to Egger as well. On the one hand, the Egger Varioseal® System was developed to be used with a variety of seals; on the other hand, the introduction of highly efficient discharge blades on the back side of the impeller is of critical importance in providing the following advantages. The reduced pressure head behind the impeller (now only about 20%) that results provides relief for the shaft seal. The concentration of particles or gases at the shaft seal is therefore completely avoided. Also, axial thrust compensation that minimizes the load on the roller bearing results.

Low life cycle costs (LCC) – long service life (MTBF) – modular design

The high degree of balance that characterizes our impellers combined with solid design of the shaft bearing guarantees high endurance of the mechanical seal and roller bearing. Egger's modular design system uses high-quality standard components to the maximum extent possible, so that these can be interchanged between different hydraulic pumps and pump sizes. That makes possible the economical storage of the minimum number of replacement parts. Because of the advantages and features described here – combined with a choice of material suited to the application and design of the hydraulics – every individual pump we make is your assurance of low life cycle costs (LCC) and long service life (MTBF). Our onsite sales representative will gladly advise you.

Axial flow pump (RPP / RPG)

Axial flow pumps are centrifugal pumps, in which the fluid is transported in a direction parallel to the pump shaft, in other words axially. In contrast to radial flow pumps, the transport stream is not redirected in axial flow machines. Axial flow pumps are mainly implemented as tubular casing pumps. A propeller-like rotor similar to the propeller on a ship sets the fluid in motion. Elbow propeller pumps are especially well suited for gentle transport at large flow rates with small discharge heads.


Stuffing box packing with easy-access seals – packing cords are quickly replaced

Stuffing box packings of the shaft seal are often still in use on elbow pumps even today. Compared to mechanical seals, higher operating costs may be required; however, they offer greater reliability against possible leakage problems and are more robust in the face of malfunctions in the system. Because packing cords have to be replaced regularly, the time consumed can be reduced to a minimum with the optional standstill seal – replacement can be carried out while the pump is standing still but without emptying the pipeline. An advantage that many of our customers treasure.

Cantilever shaft and no bearing touching the fluid

Egger's elbow propeller pumps have a cantilever shaft. Therefore, no sleeve or roller bearing is contacting the fluid – a prerequisite for applications in abrasive fluids. With corrosive fluids, the shaft must also in addition be completely protected with a protective sleeve. It will also be dry-installed into a solid bearing block equipped with roller bearings.

Pumps and valves – an overview
additional information