The invention provides a multi-working-condition multi-stage
turbine. The multi-working-condition multi-stage
turbine comprises a draft tube, a sectional type guide vane, an axial-flow
impeller, a shell, a main shaft, centrifugal impellers,
impeller rings, movable guide vanes, a balance disc, a mechanical seal, a bearing pedestal and a deep groove
ball bearing. The multi-working-condition multi-stage
turbine aims to improve the efficiency and the stability of the turbine under the variable working conditions. The multi-stage centrifugal impellers are suitable for recycling the energy with
high energy head fluid. The movable guide vanes can play a role in flow adjustment, and can also be used for adjusting the inflow angle and reducing the inflow
impact loss when the condition deviates from the designed working condition. Similarly, the sectional type guide vane is designed for adapting to different working conditions, and can effectively eliminate the circulation of
water flow in the draft tube, and therefore the
cavitation damage to the draft tube is greatly reduced, and the vibration of the draft tube is weakened.