| 摘要 |
Calibrating means, provided downstream of a die tool of an extruder, has a feed-through passage through which hollow plastics profiles are fed, the cross section of the passage corresponding to that of the profile. The surfaces (9,10) of the feed-through passage associated with the surfaces (7 and 8) of the hollow plastics profiles which will be visible in use are provided with profiling projections extending longitudinally of the passage to impress a corresponding surface profiling or structuring in the form of grooves (12) in the visible surfaces (7 and 8). The depth of the grooves (12) is within the 5 to 15 micrometer range. The visible surfaces (7 and 8) of the hollow plastics profiles thereby take on an optically matt and even looking appearance, which masks the appearance of slight recesses in the visible surfaces (7,8) which may occur between internal supporting webs of the profile, & which would otherwise be visible if the surfaces (7,8) were glossy. <IMAGE> |
