| 摘要 |
In order to avoid die slump an extruded plastic pipe (12) is twisted as it exits an extruder die 10 by arrangement of the hauler device (26) which imparts a rotational, as well as translational movement to the pipe. On exiting die 10, the pipe 12 enters a vacuum sizing cooling tank 14. The pipe 12 then enters one or more further cooling tanks 18, 20 before being drawn by hauler device 26. The hauler device may be arranged to impart the rotational and translational movements through an integrated drive mechanism, which comprises drive devices in the form of belts 28, 32 or wheels 40. |
