EXTERNAL DIAMETER MEASURING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide an external diameter measuring device which accurately measures an external diameter of a boiler tube in a relatively short period of time.SOLUTION: An external diameter measuring device to measure an external diameter of a cylindrical tube made of alloy steel comprises: a first range finder which measures a distance to a first point on a circumference on a predetermined cross section of the tube; a second range finder which is arranged opposite to the first range finder with the tube placed in between and measures the distance to a second point on the circumference opposite to the first point on the predetermined cross section of the tube; and a holding unit which holds the first and second range finders in a manner that enables an external diameter of the tube to be measured on the basis of measurement results of the first and the second range finders and is detachably installed around the tube.SELECTED DRAWING: Figure 2