| 摘要 |
The invention concerns extrusion dies for apparatus for producing seamless thermoplastic tubing. An elongate hollow core is provided extending through a bore in the extrusion head. The hollow core may carry service lines to downstream parts of the apparatus and may act as or may carry an inner mandrel extending coaxially in an extrusion nozzle. The invention provides hollow core, the diameter of which is not greater than the diameter of the bore of the extrusion head. Thus, it may be possible to withdraw the core in a downstream direction for tool changes and the like without the necessity of dismantling the extrusion head. |
