| 摘要 |
<p>In the direct extrusion of tubing wherein the extruded tube or tubing is immediately submerged into water after extrusion and having a closed leading end, the trailing end thereof in the extrusion press is sealed off from the entrance of water by a crimping device consisting of a tool having a rounded front end which engages and forces through the operation of a piston cylinder assembly one wall inwardly of the trailing end against an opposed wall to form a collapsed double wall cross section.</p> |
