METHOD AND INSTRUMENT FOR MEASURING PROFILE OF TUBULAR BODY, METHOD OF MEASURING STRESS OF TUBULAR BODY, AND CROSS-SECTIONAL FORM MEASURING INSTRUMENT FOR TUBULAR BODY

摘要

PROBLEM TO BE SOLVED: To obtain a method and instrument for measuring profile of tubular body by which the accurate profile of a tubular body can be found without being affected by the attitude of a pig main body, the temperature of a fluid flowing trough the tubular body, and so on, and to provide a method by which the stress generated in the tubular body by the depression, etc., of the tubular body can be measured and a cross-sectional form measuring instrument which can accurately measure the cross-sectional form of the tubular body.;SOLUTION: In the method of measuring profile of tubular body, the profile of the tubular body is measured based on profile data in the tubular body acquired by running a measuring pig in the tubular body. In the method, the distance in the running direction of the pig, the bearing angles of the three axes of the pig, and the relative inclination between the pig and tubular body are respectively found and the linearity of the tubular body is found based on corrected bearing angles of the three axes of the pig and the distance in the running direction by correcting the bearing angles by using the relative inclination.;COPYRIGHT: (C)2003,JPO