Multi-stage pump rotor leveling device and leveling method

The invention belongs to the technical field of nuclear power engineering, and discloses a multistage pump rotor leveling device and method.The multistage pump rotor leveling device comprises a base, a stand column and a supporting mechanism, a protrusion is arranged on the base, the stand column is located above the base, and a first through hole and a second through hole are formed in the top and the bottom of the stand column respectively; the supporting mechanism comprises a clamping assembly and a supporting base, the clamping assembly is connected to the upper portion of the supporting base, the rotor is lifted and placed on the upper portion of the supporting base, the rotor is clamped through the clamping assembly, the supporting base is located on the stand column, and a rod part of the supporting base is in threaded connection with the first through hole. The supporting base can move in the vertical direction relative to the stand column under rotation of the stand column, so that the rotor can be i