Water turbines technology

Turbine-type

According to net head and discharge we distinction in the turbine construction chaplain, Francis-and Pelton turbines. Which turbine comes to the application, decisively depends on net head (H) and discharge (Q). The following diagramme shows the area of application of the turbines for different achievement steps.

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Kaplan turbines

This type of turbine is primarily suitable for low pressure areas and large quantities of water. The head of water (1m to 40m) determines the number of blades on the rotor (3 to 6 blades). WWS supplies Kaplan turbines with vertical design with concrete or steel spirals as well as tube turbines – individual according to the requirements of your power plant. If possible, direct drive for the generator is always the better choice (no loss of efficiency). Alternatively a transmission can be offered by way of a flat belt or gear units..

Francis turbines

The Francis turbine – also know as “excess pressure turbine” – is usually installed for medium heads of water and constant water quantities. This type of turbine mostly uses a steel spiral turbine, since there is often a tube line leading to the turbine at heads of water over 20m. Further advantages of the compact design of the spiral turbine are much lower construction costs and low maintenance efforts. The preferable drive option here is also a direct drive, due to transmission losses caused by belt and gear unit solutions.

Pelton turbines

This turbine is mostly suitable for great heads of water (80m up to over 1,000m) and small water quantities. The number of nozzles (between 1 and 6) is determined by the available quantity of water and its fluctuations. The advantage of this turbine is that each single nozzle can be regulated separately if large fluctuations of water occur. The horizontal or vertical design is adjusted to the specific customer requirements.

Turbinenbau Laufräder