| 摘要 |
PROBLEM TO BE SOLVED: To quantitatively grasp a deterioration state due to thickness reduction of a lower branch line rod at an underground part without drilling buried soil near the lower branch line rod.SOLUTION: An iron core 20 is used as a deterioration measuring apparatus of a lower branch line rod 10 such as an electric pole. The iron core 20 is formed by winding an electromagnetic coil 21 to a place located at a ground part when the iron core 20 is installed and penetrated underground. In addition, in the iron core 20, a resin plate 22 is sandwiched on a contact surface with the lower branch line rod 10 so that only both ends of the iron core 20 contact the lower branch line rod 10 when the iron core 20 is installed and penetrated underground by being sealed to a side surface of the lower branch line rod 10. Then, when the electromagnetic coil 21 of the iron core 20 is set to a conducted state, a loop-shaped magnetic circuit connecting the iron core 20 with the lower branch line rod 10 is constituted. Then, a cross-sectional area S of a part constricted most due to deterioration of the lower branch line rod 10 by measuring a value of an inductance L of the magnetic circuit.SELECTED DRAWING: Figure 3 |
