摘要:
- Dispositif pour la fabrication d'un film tubulaire de structure lacunaire, du type dans lequel le film tubulaire (2) extrudé depuis une fente circulaire d'extrusion (1), reçoit une suite de perforations (5,5') disposées selon un parcours hélicoïdal le long des parois du film tubulaire, ce dernier étant à cet effet extrudé par passage entre deux couronnes circulaires non concentriques dont une couronne extérieure (3) constituant la paroi extérieure de la fente d'extrusion et une couronne intérieure (6), l'une au moins des deux couronnes étant mobile et animée d'un mouvement de nutation autour d'un axe colinéaire à l'axe de la couronne fixe, le mouvement de la couronne circulaire mobile l'amenant au contact permanent de la paroi de la couronne fixe selon un point de contact qui se déplace continûment sur le pourtour de la couronne fixe, une des couronnes comportant sur sa face en contact avec l'autre couronne des indentations propres à perforer le film dans la zone de contact entre les deux couronnes, et le dispositif est caractérisé en ce que les couronnes sont disposées de telle façon l'une par rapport à l'autre que l'action d'incision et de perforation de la couronne mobile, coopèrant avec la couronne fixe, s'opère immédiatement en aval de la fente d'extrusion (1) et sur le film (2) n'étant plus maintenu en appui sur la paroi de la couronne fixe.
摘要:
Bei dieser Vorrichtung ist der ringförmige Düsenspalt (5) von einem ortsfest am Spritzkopfgehäuse (1) gehaltenen Dorn (3) und einem den Dorn (3) umschließenden Mundstück (4) gebildet. Das Mundstück (4) ist kugelkalottenartig am Spritzkopfgehäuse (1) gelagert und mittels Schrauben (8) gesichert. Um in einfacher und sicherer Weise und ohne besondere Werkzeuge eine exakte Einstellung des Düsenspaltes (5) zu erreichen, sind außerhalb der kugelkalottenartigen Lagerung zwischen dem Spritzkopfgehäuse (1) und dem Mundstück (4) mindestens zwei ringförmige, relativ gegeneinander verdrehbare Schrägscheiben (13) und/oder mindestens drei gleichmäßig verteilte, in axialer Richtung verstellbare Abstützelemente (16) angeordnet.
摘要:
The invention relates to an extrusion head (10) for forming a tubular sheath. The extrusion head includes an annular chamber (18) having an upstream end and a downstream end (24), said upstream end comprising an inlet opening for injecting a polymer material loaded with a flow additive, said annular chamber (18) including two channels for forming two circumferential flows of polymer material in the molten state, said channels combining in a junction area (48), wherein the flow additive is concentrated in said junction area, and the junction of said two flows forms a weld joint, at which there is a concentration of flow additive, in said tubular sheath. According to the invention, said annular chamber includes an extraction pipe (52) leading into said junction area (48) in order to enable the extraction of a fraction of said polymer material, which is in the molten state and which has a concentration of flow additive, from said junction area (48).
摘要:
The invention relates to a nozzle for an extruder, having a core (1) and an at least two-part housing (2, 3), comprising a stationary main housing body (2) and an end part of the housing (3), at which the flowable mass (12) leaves the nozzle, the housing (2, 3) surrounding the core (1) in such a way that a flow channel (4) is present between the core (1) and the housing (2, 3), through which flow channel a flowable mass (12) can be discharged, characterized in that the flow channel (4) is sealed in the area of the separation between the main housing body (2) and the adjacent end part (3) by means of an elastically deformable seal (5), and the end part (3) is supported on said seal (5) such that the end part can be tilted in any direction, and to a method for changing in a specific manner or for controlling the thickness distribution of flowable masses, wherein both existing eccentric and asymmetric thickness differences can be corrected independently of each other or in a linked manner.
摘要:
The invention relates to a method and a device for the production of blow-molded two- or multi-layer containers made of thermoplastic, and a plastic container produced accordingly, having view strips, particularly for storage and for transport of liquid bulk material. To this end, molten plastic material is deflected in an extrusion head (10) from the inner, natural-colored layer (34) of the tubular premold (18) into the outer layer (36) in a process technical step, and embedded there, whereby a view strip (24) is formed in the exterior, dyed plastic layer (36).