发明名称 |
Coextrusion process for producing multiple layered thermoplastic pipe |
摘要 |
A process is disclosed for the coextrusion of a multi-layered tube whereby at least one stream of molten polymer from a single-screw extruder is passed through a die; wherein the stream is divided into two concentric streams which are balanced by varying the area of a restrictor orifice placed in the central stream. Spider lines in the outer molten stream are eliminated by the use of a second restrictor means used downstream of an open chamber for reuniting the melt, which chamber is downstream of the spider legs.
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申请公布号 |
US4499041(A) |
申请公布日期 |
1985.02.12 |
申请号 |
US19830497312 |
申请日期 |
1983.05.23 |
申请人 |
COSDEN TECHNOLOGY, INC. |
发明人 |
HAHN, GRANVILLE J.;RUTLEDGE, RALEIGH N.;MURLEY, JACKIE D. |
分类号 |
B29C47/06;B29C47/20;(IPC1-7):B29F3/04 |
主分类号 |
B29C47/06 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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