PURPOSE: To apply a piping flaw detecting head even to a nonmagnetic pipe without reference to the diameter of piping on which fault detection is to be imposed by holding the head at a desired position on the external circumference of the piping to be detected by a press-contacting mechanism through the 1st and 2nd turning wheels according to a supporting table, and then running the head freely along the external circumference by the rotation driver for the 1st turning wheels.

CONSTITUTION: A supporting arm 22 is arranged around the external circumference of piping 19 to press the 1st turning wheels 7W9 against the external circumference of the piping 19 through a supporting table body 22, and the supporting arm 22 is fitted pivotally on a bracket 20, and consequently the 1st turning rolls 7W9 and 2nd turning wheel 23 are pressed in contact with the external circumference by the compression spring of a receiving table 24, thus holding the supporting table 1. As an electric motor 6 is driven in a desired direction, the 1st turning wheel 7 is driven through a shaft joint 15, a worm shaft 4, a worm wheel 5 and rotating shaft 14 to run in the circumference direction of the piping 19, and then the supporting table 2, supporting arm 22 and receiving table 24 also move to perform fault inspection by a fault detecting head 10. A bearing cylinder 3 is fitted to the supporting table body 2 by turning up the bearing cylinder 3 through the long-sized hole 12 of a flange 11 and a bolt 13, and the electric motor 6 is put in operation, thereby moving the supporting and running device for the head in the longitudinal direction of the piping 19.