US Patent 7579831 Test device for tubular specimens

A test device for testing of tubular specimens has a plurality of individual, radially movable, finger-shaped test probes which are placed from all sides on the outside of the specimen to be tested. In this way, the test specimen is surrounded by test probes and can be pushed under them. Each test probe has a first test coil with a surface which faces essentially parallel to the lengthwise axis of the specimen and a second test coil which is oriented essentially perpendicular to the lengthwise axis of the specimen. The test probes can be elastically deflectable, pivotably movable, or movable by a screw mechanism.