| 摘要 |
There is provided a method for detecting an abnormal portion (defect, non -adhering portion, and seized portion) lying at a contact region between eac h part of a pin and each part of a box forming a threaded joint to be used a s a joint of pipe or tubes such as OCTG. This invention provides an ultrason ic testing method of a threaded joint of pipes or tubes including a pin havi ng an external thread part, a metal seal part, and a shoulder part on an out er peripheral surface, and a box having an internal thread part, a metal sea l part, and a shoulder part corresponding to each part of the pin on an inne r peripheral surface and being fastened with the pin by way of a lubricant. The method according to the present invention comprising the steps of: trans mitting and receiving ultrasonic waves to and from a plurality of locations along an axial direction of the threaded joint in at least one of the intern al thread part, the metal seal part, and the shoulder part of the box; detec ting echo intensities and reception times of echoes for the plurality of loc ations; and detecting an abnormal portion in the threaded joint based on axi al directional distribution of the echo intensities and axial directional di stribution of reception times of the echoes.
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