DE1148736B - Vacuum calibration device for plastic profiles, especially hollow plastic profiles - Google Patents

Vacuum calibration device for plastic profiles, especially hollow plastic profiles

Info

Publication number
DE1148736B
DE1148736B DEK40570A DEK0040570A DE1148736B DE 1148736 B DE1148736 B DE 1148736B DE K40570 A DEK40570 A DE K40570A DE K0040570 A DEK0040570 A DE K0040570A DE 1148736 B DE1148736 B DE 1148736B
Authority
DE
Germany
Prior art keywords
plastic profiles
vacuum
calibration device
calibration
cooling
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
DEK40570A
Other languages
German (de)
Inventor
Dipl-Ing Gebhard Schramm
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kloeckner Werke AG
Original Assignee
Kloeckner Werke AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kloeckner Werke AG filed Critical Kloeckner Werke AG
Priority to DEK40570A priority Critical patent/DE1148736B/en
Publication of DE1148736B publication Critical patent/DE1148736B/en
Pending legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/88—Thermal treatment of the stream of extruded material, e.g. cooling
    • B29C48/90—Thermal treatment of the stream of extruded material, e.g. cooling with calibration or sizing, i.e. combined with fixing or setting of the final dimensions of the extruded article
    • B29C48/901—Thermal treatment of the stream of extruded material, e.g. cooling with calibration or sizing, i.e. combined with fixing or setting of the final dimensions of the extruded article of hollow bodies
    • B29C48/903—Thermal treatment of the stream of extruded material, e.g. cooling with calibration or sizing, i.e. combined with fixing or setting of the final dimensions of the extruded article of hollow bodies externally
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
    • B29C48/09—Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/88—Thermal treatment of the stream of extruded material, e.g. cooling
    • B29C48/90—Thermal treatment of the stream of extruded material, e.g. cooling with calibration or sizing, i.e. combined with fixing or setting of the final dimensions of the extruded article
    • B29C48/904—Thermal treatment of the stream of extruded material, e.g. cooling with calibration or sizing, i.e. combined with fixing or setting of the final dimensions of the extruded article using dry calibration, i.e. no quenching tank, e.g. with water spray for cooling or lubrication
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/88—Thermal treatment of the stream of extruded material, e.g. cooling
    • B29C48/90—Thermal treatment of the stream of extruded material, e.g. cooling with calibration or sizing, i.e. combined with fixing or setting of the final dimensions of the extruded article
    • B29C48/905—Thermal treatment of the stream of extruded material, e.g. cooling with calibration or sizing, i.e. combined with fixing or setting of the final dimensions of the extruded article using wet calibration, i.e. in a quenching tank
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/88—Thermal treatment of the stream of extruded material, e.g. cooling
    • B29C48/911—Cooling
    • B29C48/9115—Cooling of hollow articles
    • B29C48/912—Cooling of hollow articles of tubular films
    • B29C48/913—Cooling of hollow articles of tubular films externally
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/88—Thermal treatment of the stream of extruded material, e.g. cooling
    • B29C48/919—Thermal treatment of the stream of extruded material, e.g. cooling using a bath, e.g. extruding into an open bath to coagulate or cool the material

Description

Vakuum-Kalibriervorrichtung für Kunststoffprofile, insbesondere Kunststoffhohlprofile Die Erfindung bezieht sich auf Vakuum-Kalibriervorrichtungen für Profile, insbesondere Hohlprofile aus Kunststoff, bei denen auf der Außenseite des das Kaliber bildenden Formteiles eine Vakuum- und eine Kühlkammer nebeneinander angeordnet sind und das kaliberbildende Formteil im Bereich der Vakuumkammer eine gasdurchlässige Wand besitzt. Vacuum calibration device for plastic profiles, in particular plastic hollow profiles The invention relates to vacuum calibration devices for profiles, in particular Hollow profiles made of plastic, in which on the outside of the forming the caliber Molded part a vacuum and a cooling chamber are arranged side by side and that Caliber-forming molding has a gas-permeable wall in the area of the vacuum chamber.

Bei den bekannten Vakuum-Kalibriervorrichtungen sind die gasdurchlässigen Wandungen mit Löchern oder Schlitzen versehen, durch die auf das durch die Kalibriervorrichtung hindurchgeführte plastische Material eine Saugwirkung ausgeübt wird, um dasselbe fest an die Innenwandung der Kalibriervorrichtung anzudrücken. Diese Kalibriervorrichtungen weisen darin gewisse Schwierigkeiten auf, daß die vorgesehenen Bohrungen oder Schlitze kaum unter 1 mm Durchmesser hergestellt werden können. Man müßte ungefähr 50 Bohrungen je Quadratzentimeter vorsehen, um annähernd die gleiche Ansaugwirkung wie bei einem gesinterten Werkstoff zu erreichen. Das Herstellen so vieler kleiner Bohrungen ist aber äußerst schwierig und kostspielig. Außerdem kann die Ansaugwirkung in bezug auf den Bohrungsdurchmesser oder die Bohrlochanzahl bei solchen Kalibrierwerkzeugen nicht geändert werden, wenn es einmal mit Bohrungen versehen ist. Besondere Scllwierigkeiten ergeben sich bei diesen bekannten Kalibriervorrichtungen, wenn die Kalibrierdüse nicht rund, sondern abgewinkelt ist. weil das Anbringen von Bohrungen mit kleinstem Durchmesser gerade in den abgewinkelten Bereichen praktisch nur sehr schwer durchführbar ist, obwohl gerade in den Ecken starke Ansaugkräfte vorhanden sein müssen. Wenn man zu größeren Bohrungen oder Schlitzen übergehen will, um die Herstellungsschwierigkeiten zu verkleinern, so läßt sich mit solchen Werkzeugen keine ausreichend glatte Profiloberfläche mehr erzeugen. The known vacuum calibration devices are gas-permeable Walls provided with holes or slots through which the calibration device plastic material passed through a suction is exerted to the same to press firmly against the inner wall of the calibration device. These calibration devices have certain difficulties that the holes or slots provided can hardly be produced below 1 mm in diameter. You would need about 50 holes for each square centimeter to provide approximately the same suction effect as with one to achieve sintered material. Making so many tiny holes is but extremely difficult and costly. In addition, the suction can be related on the bore diameter or the number of boreholes for such calibration tools cannot be changed once it has been drilled. Particular difficulties arise with these known calibration devices when the calibration nozzle is not round, but angled. because the drilling of holes with the smallest Diameter, especially in the angled areas, is very difficult to carry out in practice although strong suction forces must be present, especially in the corners. if you want to go to larger bores or slots to overcome the manufacturing difficulties To reduce the size, such tools cannot be used to achieve a sufficiently smooth profile surface generate more.

Die Erfindung vermeidet die genannten Nachteile der bekannten Kalibriervorrichtungen. Sie ist dadurch gekennzeichnet, daß das kaliberbildende Formteil im ganzen von der Vakuum- und der Kühlkammer gebildeten Bereich eine durchlässige Wand aus porösem Werkstoff aufweist. The invention avoids the mentioned disadvantages of the known calibration devices. It is characterized in that the caliber-forming part of the whole Vacuum and the cooling chamber formed a permeable wall made of porous Has material.

Ein besonderer Vorteil der erfindungsgemäßen Kalibriervorrichtung besteht darin, daß auf Grund des in der Vakuumkammer herrschenden Unterdruckes das Kühlmedium durch die poröse Wandung in die Vakuumkammer gesaugt wird und hierdurch eine sehr intensive Kühlung des Kalibrierrohres in unmittelbarem Anschluß an die Saugstrecke erfolgt. A particular advantage of the calibration device according to the invention is that due to the negative pressure prevailing in the vacuum chamber the Cooling medium is sucked through the porous wall into the vacuum chamber and thereby a very intensive cooling of the calibration tube immediately following the Suction section takes place.

Gerade die sich in den porösen Wandungsteilen der Kalibriervorrichtung ausbildende Kühlmittelströmung gestattet mit Sicherheit die formhaltende Abkühlung des Kunststoffes. Bei den beschriebenen bekannten Kalibriervorrichtungen ist eine solche vorteilhafte Kühlwirkung nicht zu erreichen, weil die über die Bohrungen der Vakuumkammer angesaugte Profiloberfläche die Bohrungen oder sonstigen Öffnungen verschließt, so daß das Kühlwasser in den Bereich zwischen Profiloberfläche und Kalibrierdüse praktisch nicht eindringen kann.Just those in the porous wall parts of the calibration device developing coolant flow certainly allows shape-retaining cooling of the plastic. In the known calibration devices described is a Such an advantageous cooling effect cannot be achieved because of the holes the profile surface sucked into the vacuum chamber, the holes or other openings closes so that the cooling water in the area between the profile surface and Calibration nozzle can practically not penetrate.

Als poröser Werkstoff kann beispielsweise ein Sintermetall Venvendung finden. A sintered metal, for example, can be used as the porous material Find.

Beim Erfindungsgegenstand entfällt die Anbringung vieler kleiner Bohrungen; außerdem ist die Ansaugwirkung besser, als dies mit einer Wandung erreichbar ist, die eine Vielzahl kleinster Bohrungen aufweist; die Oberflächenbeschaffenheit ist naturgemäß tadellos und weist keine Unregelmäßigkeiten auf Grund von Bohrungen oder sonstigen Öffnungen in der Wandung der Kalibriervorrichtung auf. Da gesinterte Werkstoffe in verschiedenen Porositätsgrößen im Handel erhältlich sind, kann man mit einem gesinterten Werkstoff die Ansaugwirkung mit geringstem Arbeitsaufwand und niedrigen Kosten verändern. With the subject of the invention, the attachment of many smaller ones is not required Drilling; in addition, the suction effect is better than can be achieved with a wall is, which has a plurality of very small bores; the surface finish is naturally flawless and has no irregularities due to holes or other openings in the wall of the calibration device. Since sintered Materials in different porosity sizes are commercially available, one can with a sintered material, the suction effect with the least amount of work and change at low cost.

In den Figuren ist ein Ausführungsbeispiel der Erfindung veranschaulicht. An exemplary embodiment of the invention is illustrated in the figures.

Fig. 1 ist ein Schnitt durch die Längsachse der erfindungsgemäßen Kalibriervorrichtung; Fig. 2 ist in größerem Maßstab ein Teilausschnitt aus der Kalibriervorrichtung, der zur Veranschaulichung des Kühlwasserverlaufs dient. Fig. 1 is a section through the longitudinal axis of the invention Calibration device; Fig. 2 is a partial section from the larger scale Calibration device, which is used to visualize the course of the cooling water.

Die Kalibrierdüse 1 ist in das Kühlbecken 2 eingesetzt, wobei das Vakuum über die Ringkammer 3 dem Sintermetallfilter 4 zugeführt wird. Die Ringkammer 3 ist mittels des Stutzens 5 an eine nicht veranschaulichte, genügend starke Pumpe angeschlossen. Neben der Ringkammer 3 befindet sich die Ringkammer 6, die wie das Kühlbecken mit Kühlwasser gefüllt ist. Das plastische Hohlprofil, welches von der nicht veranschaulichten Schneckenpresse zugeführt wird, gelangt in Richtung des Pfeils 7 in das Kalibrierwerkzeug, wo es an das Metallfilter 4 angesaugt und gekühlt wird, so daß es seine endgültige Form erhält. Am Ausgang des Kalibrierwerkzeuges ist ein Simmerring 8 vorgesehen, der den Spalt zwischen Kalibrierwandung und Kunststoffrohr gegen Zutritt von Wasser aus dem anschließenden Kühlbecken abdichtet. The calibration nozzle 1 is inserted into the cooling basin 2, the Vacuum is supplied to the sintered metal filter 4 via the annular chamber 3. The ring chamber 3 is by means of the connector 5 to a not illustrated, sufficiently powerful pump connected. Next to the annular chamber 3 is the annular chamber 6, which like that Cooling basin is filled with cooling water. The plastic hollow profile, which is used by the not illustrated screw press is fed, arrives in the direction of the Arrow 7 into the calibration tool, where it is sucked onto the metal filter 4 and cooled so that it takes its final shape. At the output of the calibration tool a Simmerring 8 is provided, which closes the gap between the calibration wall and the plastic pipe seals against the ingress of water from the adjoining cooling basin.

In Fig. 2 ist der Verlauf des Kühlwassers von der Kühlkammer 6 in die Vakuumkammer 3 durch Pfeile veranschaulicht. Wie aus der Figur ersichtlich ist, fließt das Kühlwasser in das Metallfilter und bewirkt eine intensive Kühlung, ohne jedoch das durchgeführte Kunststoffrohr selbst zu berühren, weil das Vakuum ausreichend stark ist, um die in der Metallfilterwand befindliche Flüssigkeit anzusaugen und in die Vakuumkammer abzuführen. In Fig. 2, the course of the cooling water from the cooling chamber 6 in the vacuum chamber 3 illustrated by arrows. As can be seen from the figure, the cooling water flows into the metal filter and causes intensive cooling without however touching the plastic pipe passed through because that Vacuum sufficient is strong to suck in the liquid located in the metal filter wall and to be discharged into the vacuum chamber.

Claims (1)

PATENTANSPRUCH: Vakuum-Kalibriervorrichtung für Profile, insbesondere Hohlprofile aus Kunststoff, bei der auf der Außenseite des das Kaliber bildenden Formteiles eine Vakuum- und eine Kühlkammer nebeneinanderliegend angeordnet sind und das kaliberbildende Formteil im Bereich der Vakuumkammer eine gasdurchlässige Wand besitzt, dadurch gekennzeichnet, daß das kaliberbildende Formteil im ganzen von der Vakuum- und der Kühlkammer gebildeten Bereich eine durchlässige Wand aus porösem Werkstoff aufweist. PATENT CLAIM: Vacuum calibration device for profiles, in particular Hollow profiles made of plastic, in the case of which on the outside of the forming the caliber Molded part a vacuum and a cooling chamber are arranged side by side and the caliber-forming molded part in the area of the vacuum chamber is a gas-permeable one Wall, characterized in that the caliber-forming molded part as a whole A permeable wall is formed from the area formed by the vacuum chamber and the cooling chamber having porous material. In Betracht gezogene Druckschriften: Britische Patentschrift Nr. 780 900; französische Patentschrift Nr. 1 208 352. Documents considered: British Patent No. 780 900; French patent specification No. 1 208 352.
DEK40570A 1960-04-30 1960-04-30 Vacuum calibration device for plastic profiles, especially hollow plastic profiles Pending DE1148736B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
DEK40570A DE1148736B (en) 1960-04-30 1960-04-30 Vacuum calibration device for plastic profiles, especially hollow plastic profiles

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DEK40570A DE1148736B (en) 1960-04-30 1960-04-30 Vacuum calibration device for plastic profiles, especially hollow plastic profiles

Publications (1)

Publication Number Publication Date
DE1148736B true DE1148736B (en) 1963-05-16

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DEK40570A Pending DE1148736B (en) 1960-04-30 1960-04-30 Vacuum calibration device for plastic profiles, especially hollow plastic profiles

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2504190A1 (en) * 1975-02-01 1976-08-05 Dynamit Nobel Ag METHOD AND DEVICE FOR REDUCING THE SHRINKAGE OF EXTRUDED PROFILE STRIPS MADE OF THERMOPLASTIC PLASTICS
DE2809386A1 (en) * 1978-03-04 1979-09-06 Dynamit Nobel Ag METHOD AND DEVICE FOR CALIBRATING PROFILES MADE OF THERMOPLASTIC PLASTIC BY USING VACUUM PRESSURE
EP0573907A1 (en) * 1992-06-10 1993-12-15 CONPRO GmbH Extruder with wall thickness measuring device
DE102005060187A1 (en) * 2005-12-14 2007-06-21 Breyer Gmbh Maschinenfabrik Calibration tool for plastic melt has part or all of calibration plate surface made of sintered metal or with a sintered metal structure formed on it

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB780900A (en) * 1954-07-15 1957-08-07 Hans Reifenhaeuser Method of and apparatus for forming and/or shaping tubing or other tubular workpieces of thermoplastic material
FR1208352A (en) * 1957-06-11 1960-02-23 Du Pont Forming of plastics under gas pressure

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB780900A (en) * 1954-07-15 1957-08-07 Hans Reifenhaeuser Method of and apparatus for forming and/or shaping tubing or other tubular workpieces of thermoplastic material
FR1208352A (en) * 1957-06-11 1960-02-23 Du Pont Forming of plastics under gas pressure

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2504190A1 (en) * 1975-02-01 1976-08-05 Dynamit Nobel Ag METHOD AND DEVICE FOR REDUCING THE SHRINKAGE OF EXTRUDED PROFILE STRIPS MADE OF THERMOPLASTIC PLASTICS
DE2809386A1 (en) * 1978-03-04 1979-09-06 Dynamit Nobel Ag METHOD AND DEVICE FOR CALIBRATING PROFILES MADE OF THERMOPLASTIC PLASTIC BY USING VACUUM PRESSURE
US4468369A (en) * 1978-03-04 1984-08-28 Dynamit Nobel Aktiengesellschaft Process for the vacuum calibration of profiled articles made of thermoplastic synthetic resin
EP0573907A1 (en) * 1992-06-10 1993-12-15 CONPRO GmbH Extruder with wall thickness measuring device
DE102005060187A1 (en) * 2005-12-14 2007-06-21 Breyer Gmbh Maschinenfabrik Calibration tool for plastic melt has part or all of calibration plate surface made of sintered metal or with a sintered metal structure formed on it

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