| 摘要 |
PURPOSE:To inspect the existence of a defect of a pipe by forming a couple of annular coils covering the whole periphery of the pipe by combining plural coil units and connecting an oscillator with a bridge circuit and calculating the difference of mutual electromagnetic characteristics between the annular coils. CONSTITUTION:A main body 1 of an inspection instrument for the pipe P is formed so that a storage part 3A storing the unit coils 2A and 2B and a storage part 3B storing the unit coils 2C and 2D are enabled to turn with an axis 4 as a center and arranged around the pipe. Further, the coils 2A-2D are made in the semi-circular arcuate shapes by folding the annular coils double and 2A and 2B, 2C and 2D are arranged in the opposing states and functioned as a couple of annular coils 6A and 6B. Then, these coils are connected with a measuring circuit consisting of the oscillator and the bridge circuit and the difference of the electromagnetic characteristics between the coils 6A and 6B is calculated. Consequently, the existence of the defect can be inspected with the pipe while working and the handling can be improved. |
