| 摘要 |
PURPOSE:To give fatigue to the bottom part of a rod material repeatedly and to cut and collect the rod material by inserting a cylindrical constraint collar after excavating a base material at the outer-diameter circumference of the rod material to be sampled, and putting it in circular pendulum motion through a rotating tool together with the rod material. CONSTITUTION:On the base material consisting of a structural material 1 and a corrosion preventive material 2, a template 3 is provided to position a heat conduction pipe hole, which is machined with a die. A test-piece sampling position, a guide bush is fitted and shallow machining is performed by a core drill 4. Then, a constraint collar 6 is fitted around a rod material 5, and a slant cut bar 7 while rotated is lowered into the space part between the outer-diameter side of said collar 6 and excavated base materials 1 and 2. Then, the constraint collar 6 abuts on the slanting surface of the slant cut bar 7 to apply bending stress to the bottom part of the rod material 5. Therefore, the rod material has circular pendulum motion based upon the bottom part as a fulcrum, thereby cutting the bottom part in about 10sec. |
