Replacing a stub shaft bearing for a hydroelectric turbine using a runner hub lifting device

A method for lifting a runner hub installed in a hydroelectric unit using a runner hub lifting device, comprising:

• moving the runner hub lifting device into a discharge ring of the hydroelectric unit, wherein the discharge ring surrounds a runner including the runner hub;
• positioning the runner hub lifting device within the discharge ring so that a centerline of the runner hub lifting device is aligned with a centerline of the runner hub;
• activating at least one hydraulic ram of the runner hub lifting device so that a hub support plate of the runner hub lifting device moves towards the runner hub and the hub support plate contacts the runner hub, wherein a top surface of the hub support plate is curved to match a curve of the runner hub;
• fixing a bottom plate of the runner hub lifting device to an inner surface of the discharge ring below the runner hub;
• and
• further activating the at least one hydraulic ram of the runner hub lifting device to lift the runner hub from a first position to a second position,
• wherein the runner hub lifting device includes at least one base support mounted to the bottom plate, a ram base plate mounted to an end of the base support opposite the bottom plate, the at least one hydraulic ram mounted on the ram base plate, and the hub support plate mounted to the at least one hydraulic ram opposite the ram base plate,
• wherein the runner hub lifting device further comprises at least one hub support, and
• wherein the method further comprises inserting the at least one hub support between the ram base plate and the hub support plate when the runner hub reaches the second position.