Extrusion Asia Edition 1-2016

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Multi-Manifold Tooling Enhances Quality & Production
Efficiency: For delivery of molten polymer from extruders to a
multi-manifold die, Nordson EDI engineers distribution blocks,
situated just upstream of the die, in a variety of optional confi-
gurations. The simplest versions have a fixed design, delivering
the polymer melts to the entrances of the multi-manifold die in
only one, dedicated layer sequence arrangement. More sophi-
sticated distribution blocks provide the ability to re-route melt
streams to change the sequence of the layers via exchangeable
selector plates. The most advanced distribution blocks, in addi-
tion to selector plates, include feedblock sub-assemblies which
combine some of the melt streams prior to the die, allowing for
product versatility and for a greater number of layers than the
number of manifolds that are in the die.
Having built more multi-manifold dies than any other manufac-
turer, Nordson EDI has applied its experience to make them trou-
ble-free. Many Nordson EDI four- and five-manifold dies are in
operation without leakage issues, even at throughput rates ap-
proaching 5,000 kg/h. For the new nine-manifold die, Nordson
EDI designed for additional fasteners outboard of the main die
bodies (in the end plate assembly area) to ensure proper sealing.
Nordson EDI can custom-design its Ultracart™ rapid cleaning
station for a customer’s specific multi-manifold die. In additi-
on, the Autoflex automatic lip adjusting units on the die are
modular and can be readily detached, allowing convenient ac-
cess to the die body fasteners. These systems make disassembly
and reassembly simpler for periodic cleaning and preventative
maintenance of the die.
Nordson EDI Offers Many Alternatives for Producing Mul-
ti-Layer Film: The nine-manifold die is the latest in a wide ran-
ge of coextrusion options available from Nordson EDI. The die
system that Nordson EDI recommends for a given application
depends on such variables as overall throughput rate, layer
thickness and viscosity ratios, die width, number and type of
product structures needed, and whether the melt processing
temperatures for any of the melt streams are distinctly diffe-
rent. While the recommended solutions could range from a sin-
gle-manifold die with feedblock to a full multi-manifold die
with separate channels for all layers, often the recommendati-
on falls between these extremes, combining multi-manifold
and feedblock approaches. For example, if a five-layer structure
included only one unique and critical cap layer, then a dual-ma-
nifold die might be recommended: The critical layer would
spread through its own flow channel and the other four more
compatible layers would be coextruded through the second
flow channel.
Even as it develops advances in multi-manifold dies, Nordson
EDI is committed to innovation in feedblock design, noted Mr.
Iuliano. “Depending on the particular processing scenario, a
single manifold die with a coextrusion feedblock may be the
best way forward – for example, in a case where the extrusion
tooling needs to produce many different structures with vastly
different layer ratios. The feedblock approach generally allows
for more product versatility as well as simpler cleaning and pro-
duct changeover procedures. The multi-manifold approach is
superior, however, in terms of product quality and consistency.
Today, this approach is more than ever a practical, realistic al-
ternative for producers of higher-order multi-layer film.”
定的多层复合模头定制设计 Ultracart™ 快速清洁站。此
外，模头上的 Autoflex 自动唇口调节装置是一种模块化组
件，可以随时拆下，因此可以很方便地接触到模身紧固件。
系统拆卸和组装方便，有利于模头的定期清洁和预防性维
护。
Nordson Extrusion Dies Industries 为制造多层薄膜提供了众
多备选方案
Nordson Extrusion Dies Industries 推出了诸多可选的共
挤方案，九流道模头便是其中的最新成果。Nordson Extrusi-
on Dies Industries 为特定的应用领域推荐的模头系统取决于
一系列变量，例如总体产量、层厚和粘度比、模头宽度、所
需的产品结构数量和类型，以及各层熔体工艺温度是否存在
明显差异。推荐的解决方案可以覆盖从配备喂料块的单流道
模头，到每个复合层具有单独流道的多层复合模头。但
是，推荐的解决方案往往介于这些极端方案之间，通常结合
多流道方案与喂料块方法。例如，如果一个五层结构中仅包
含一个与其他几层都不相同的关键表层，则可能会建议采用
双流道模头：关键表层会使用专用流道内铺展，而其他四个
彼此相容的层则通过第二个流道完成共挤过程。
Iuliano 先生指出，Nordson Extrusion Dies Industries虽然在
多层复合模头领域中取得了一系列成果，但仍然致力于喂料
块设计的不断创新。“在某些特殊的加工场景中，配备复合共
挤喂料块的单流道模头从长远来看可能是最佳方法。例如，
在需要用挤出层比差异极大的多种结构时。共挤块方法通常
可以提高产品的多功能性，简化模头清理和产品转换的过
程。但在产品质量和一致性方面，多流道模头则更胜一筹。
如今，对于高端多层薄膜的生产商而言，这种方法无论实用
性还是可行性都超过了以往的任何替代方案。”
Nordson Polymer Processing Systems, Nordson EDI
22 薄膜挤出 Extrusion Asia Edition 1/2016
Nordson Extrusion
Dies Industries 的 Ultracart™
快速清洁站可以设计为适合九流道模头。
此处显示的是一个拆解后的三流道模头。
Nordson EDI’s Ultracart™ rapid cleaning station
can be designed to accommodate 9-manifold dies. Disassem-
bled die shown here is a 3-manifold unit