Wellhead auxiliary positioning device of spent fuel vertical shaft and positioning label auxiliary mounting system

The utility model discloses a spent fuel vertical shaft wellhead auxiliary positioning device which comprises at least three supporting arms, the first ends of the supporting arms are connected, center mark points are arranged at the connecting positions of the supporting arms, the second ends of the supporting arms are outward extending ends, and the center mark points are arranged at the connecting positions of the supporting arms. The distances from the end parts of the outward extending ends of the supporting arms to the central marking point are equal; and the outward-extending adjusting pieces are arranged in one-to-one correspondence with the supporting arms, are arranged at the outward-extending ends of the supporting arms and are used for adjusting the lengths of the portions, extending out of the outward-extending ends, of the supporting arms. The utility model can quickly find the actual center of the wellhead of the fuel vertical shaft. The utility model further discloses an auxiliary installation