| 摘要 |
<p>Narrow slit extruder is provided adjacent the slit with a movable slit adjusting element and a sealing strip. Between the element and a web of the U-shaped element is a hydraulically expansible hose which in the expanded state presses the strip against the end faces of the slit, and which is connected to an adjustable pressure source. The adjusting element may be set automatically by releasing of sealing strip. Strip which can be of light construction is capable of with standing high stresses. To prevent clogging of the sealing strip by solidified plastics melt and imparing the function of the strip, the latter may be associated along its longitudinal edges with sealing elements made of PTFE.</p> |
