METHOD OF MEASURING SHAPE OF END OF TUBE WITH SCREW

PROBLEM TO BE SOLVED: To precisely and speedily measure shapes of a screw part and a seal part formed at an end of a tube with a screw.SOLUTION: There is provided a method of measuring the shape of an end of a tube with a screw, the method including a screw axis detecting process, a laser light positioning process, a laser light imaging process, and a shape calculating process. In the laser light positioning process, a light source and imaging means 2 are moved in one body so that the optical axis LA of the light source 1 is located so as to pass through a measurement point D (X1, Y1, Z1) on a screw axis A at a measurement object point in a plane NP containing the screw axis A, and the laser light L spreads in a slit shape in the plane PN.