| 摘要 |
1282812 Detecting flaws in welds in continuously welded tubes F FÍRSTER 21 April 1970 19076/70 Headings G1N and G1S A method of detecting internal discontinuities within the weld of a continuously welded tube comprises increasing the sensitivity of a non-destructive weld flaw test to discontinuities which may be present in a part of the weld by bending the weld so that the said part is subjected to a tensile deformation before or during the test. As described the tube is plastically deformed by diametric compression in the plane of the weld 1, 2 and at right angles to this plane (6, 7) Fig.2 (not shown) so that, respectively, the inside of the weld 3 is deformed 4, 5, and the outside of the weld 3 is deformed (8, 9). The following test methods are listed as suitable, magnetic stray flux, magnetographic, ultrasonic and eddy current. The sensitivity may be increased further by applying the test method before and after the deformation and comparing the recorded results. |
