摘要 |
<p>The machine (1) for the formation of tubes (2) comprises at least, in series with each other, forming stations (3, 3') comprising pairs of idle rollers (8, 8') which make rototranslational movements of the same amplitude but in opposite directions, and at least one finishing station (5) comprising four idle rollers (91) having a concave profile with a constant curvature and able to perform rototranslational movements of the same amplitude and direction according to 90° axes. The lower rollers (8') of each forming station (3, 3') have an elliptical profile with a curvature decreasing form the outer edge to the inner edge of said roller (8'). The upper rollers (8) of the first forming station (3) have an elliptical profile with a curvature increasing from the outer edge to the inner edge of said roller (8); the upper rollers (8") of the forming stations (3') subsequent to the first (3) have a circular profile.</p> |