Hydroelectric Francis Water Turbine Generator From 50 to 250kw

Micro Francis turbine is suitable for water power stations with medium or low water head and flow rates. It consists of a water guiding chamber, runner, water distributor, and draft tube. The functions and conformations of these parts are introduced as follows.

1) Water guiding chamber: There are metal spiral cases and metal tanks two types of water guiding chambers are generally used. Its main function is to guarantee water enters the water distributor evenly and symmetrically in order to reduce the loss of water head. The Spiral case is the best choice for turbine behavior.

The advantages of the metal tank type are simple in conformation and low in cost, but the loss of water head is bigger than spiral case. So it is generally used in small turbines.

2) Runner: Runner is a key part of the turbine. Hydraulic energy is transferred to mechanical energy by the runner. The runner of the Francis turbine consists of vanes, runner hub, and torus. Radial water flow is changed to axial flow by vanes. The number of vanes can be 10 to 24 pieces. The usual quantity is 14 to 17 pieces. Vanes, runner hub, and torus can be made by inblock cast, or by separate cast and welding.

3) Water distributor: Water distributor has the following function.
Guide water enters the runner from the best direction. Adjust the flow rate of water in a runner to fit the outside load change. For start or stop of the generator set.

Francis turbine generator unit:
A mixed hydro turbine has radical inflow into a runner, and axle outflow from the runner, which is referred to as Francis hydro turbine. The features of the Francis turbine are simple structure and reliable operation; high efficiency, suitable for water head of 10 m-70 m, which is currently one of the most widely used. There are vertical shafts and horizontal shaft Francis turbine.