| 摘要 |
PROBLEM TO BE SOLVED: To provide a defect inspection method for a honeycomb structure, enabling a defect in a skin layer to be detected.SOLUTION: The defect inspection method for a honeycomb structure is provided for inspecting a defect in a honeycomb structure 1 composed of porous ceramic having a number of cells 12 surrounded by a number of cell walls 11 and a cylindrical skin layer 13 covering an outer peripheral side surface of the honeycomb structure by performing a detection step and a determination step. In the detection step, both ends 14, 15 of the honeycomb structure 1 in a flow channel direction X is hermetically sealed, and gas 3 is fed into the honeycomb structure 1 from one end 14 toward the other end 15 of the honeycomb structure 1 in the flow channel direction X. Then, microphones 2 disposed at the outer periphery of the skin layer 13 detect the sound of the gas 3 leaking from the skin layer 13. In the determination step, it is determined whether or not there is a defect composed of a hole of a diameter of a predetermined size or larger or a penetrating crack existing in the skin layer 13, on the basis of the level of the sound detected in the detection step. |
