METHOD AND SYSTEM FOR CALCULATING MISALIGNMENT OF ROTATIONAL BODY

In a method of calculating misalignment of a rotational body, radial displacement values are measured using a displacement gauge. A calculation part performs the steps of deriving radial displacement amounts of the rotational body for at least four or more measurement points along an outer surface while rotating the rotational body, selecting three arbitrary points to calculate a circle, calculating circle values for all the measurement points, calculating differences between the calculated circle values and the radial displacement amounts as error amounts, summing the error amounts to derive a total error amount, repeating circle calculation for different combinations and calculating a total error amount for each calculated circle, selecting a circle with a minimum total error amount as a most probable circle, and calculating deviation between the center of the most probable circle and the center of rotation of the rotational body.