摘要 |
<p>This device makes it possible to draw a tube (2) through a die (1) on a drawing bench and comprises a mandrel (3, 4, 5) accommodated inside the tube. On its cylindrical part in line with the die, in its smallest part (5) and over all or part of its length, this mandrel comprises helical ribs. Drawing then causes the mandrel to rotate, thus producing the rifling of the inside of the tube. <IMAGE></p> |