DE2723991A1 - Annular plastic extrusion nozzle control - for uniform pressure distribution with pressure pick=ups and computer - Google Patents
Annular plastic extrusion nozzle control - for uniform pressure distribution with pressure pick=ups and computerInfo
- Publication number
- DE2723991A1 DE2723991A1 DE19772723991 DE2723991A DE2723991A1 DE 2723991 A1 DE2723991 A1 DE 2723991A1 DE 19772723991 DE19772723991 DE 19772723991 DE 2723991 A DE2723991 A DE 2723991A DE 2723991 A1 DE2723991 A1 DE 2723991A1
- Authority
- DE
- Germany
- Prior art keywords
- pressure
- annular gap
- nozzle
- transducers
- voltage values
- 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.)
- Withdrawn
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
- B29C48/30—Extrusion nozzles or dies
- B29C48/32—Extrusion nozzles or dies with annular openings, e.g. for forming tubular articles
- B29C48/325—Extrusion nozzles or dies with annular openings, e.g. for forming tubular articles being adjustable, i.e. having adjustable exit sections
- B29C48/327—Extrusion nozzles or dies with annular openings, e.g. for forming tubular articles being adjustable, i.e. having adjustable exit sections with centering means
-
- 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
- B29C48/03—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
- B29C48/10—Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels flexible, e.g. blown foils
-
- 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
- B29C48/30—Extrusion nozzles or dies
- B29C48/32—Extrusion nozzles or dies with annular openings, e.g. for forming tubular articles
-
- 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
- B29C48/92—Measuring, controlling or regulating
-
- 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
- B29C2948/00—Indexing scheme relating to extrusion moulding
- B29C2948/92—Measuring, controlling or regulating
- B29C2948/92504—Controlled parameter
- B29C2948/92514—Pressure
-
- 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
- B29C2948/00—Indexing scheme relating to extrusion moulding
- B29C2948/92—Measuring, controlling or regulating
- B29C2948/92504—Controlled parameter
- B29C2948/92571—Position, e.g. linear or angular
-
- 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
- B29C2948/00—Indexing scheme relating to extrusion moulding
- B29C2948/92—Measuring, controlling or regulating
- B29C2948/92819—Location or phase of control
- B29C2948/92857—Extrusion unit
- B29C2948/92904—Die; Nozzle zone
Abstract
Description
Verfahren zum Zentrieren von Ringspaltdüsen bei Procedure for centering annular gap nozzles
der Verarbeitung von Kunststoffen Die Trfindung betrifft ein Verfahren zum Zentrieren von flingspaltdiisen bei der Verarbeitung von Kunststoffen z.B. zu Hohren oder Schläuchen oder aber auch z.B. zu Vorformlingen für den Extrsionsblasformprozeß, sowie eine Vorrichtung zur Durchführung dieses Verfahrens. the processing of plastics The discovery concerns a process for centering flingspaltdiisen when processing plastics e.g. to Tubes or hoses or, for example, to preforms for the extrusion blow molding process, and a device for performing this method.
Bei derartigen Ringspaltdijsen ist es notwendig, daß iiber den ganzen Umfa.nv des Extrudates (Vorformlings bzw. Rohres oder Schlauches) eine gleichrnßige Wanddicke vorhanden ist. Dies ist generell us Gründen der Wirtschaftlichkeit (Materialersparnis, Verringerung der kühlzeit) wünschenswert. Speziell beim Extrusionsblasformprozeß ist es außerdem verfahrenstechnisch notwendig, daß der Vorformling zur Weiterverarbeitung (Aufblasen In der Blasform) genau senkrecht aus der Ringspaltdiise austritt, was nur dann erreichbar ist, wenn beim Austritt des extrudates aus der Ringspaltdüse am ganzen Umfang eine gleichmäßige Wanddicke vorhanden ist.With such annular gap nozzles it is necessary that over the entire Umfa.nv of the extrudate (preform or tube or hose) a uniform Wall thickness is present. This is generally for reasons of economy (material savings, Reduction of the cooling time) is desirable. Especially in the extrusion blow molding process It is also procedurally necessary that the preform for further processing (Inflate in the blow mold) exits exactly vertically from the annular gap nozzle, what can only be achieved if the extrudate exits the annular gap nozzle there is a uniform wall thickness over the entire circumference.
Da es fertigungstechnisch sehr aufwendig ist, die Ringspaltdüsen so herzustellen, daß Dorn und Düse fest angeordnet kon-7.entrisch zueinander liegen, sind sie in der Regel so gebaut, daß Dilse und Dorn in radialer Richtung gegeneinander verschoben werden können. Die Zentrierung erfolgt dabei durch Einstellen von Hand entweder mit einer entsprechenden Lehre vor dem Anfahren der Anlage oder aber mittels Stellschrauben während des Extrusionsprozesses.Since it is very complex to manufacture, the annular gap nozzles do so to establish that the mandrel and nozzle are firmly arranged con-7.entrically to one another, they are usually built in such a way that the dilse and mandrel face each other in a radial direction can be moved. The centering is done by adjusting it by hand either with a corresponding gauge before starting up the system or by means of Adjusting screws during the extrusion process.
Bei der einer weiter fortschreitenden Automatisierung der Extrusionsprozesse, besonders im Hinblick auf eine Prozeßrechnersteuerung liegt daher der Erfindung die Aufgabe zugrunde, auch die Zentrierung der Ringspaltdüsen automatisch vorzunehmen.With the advancing automation of the extrusion processes, especially with regard to a process computer control therefore lies The invention is based on the task of automatically centering the annular gap nozzles to undertake.
Diese Aufgabe ist erfindungsgemäß durch ein Verfahren gelöst, bei dem die Schmelzedruckverteilung im Ringspalt im selben Querschnitt der Ringspaltdüse fortlaufend an mindestens 3 gleichmäßig über den Umfang verteilten Stellen gemessen wird und daß in Abhängigkeit von diesen in einer Recheneinrichtung automatisch verarbeiteten Meßwerten die Ringspaltdüse gegenüber dem feststehenden Düsendorn in den jeweils erforderlichen Richtungen solange automatisch verstellt wird, bis an allen 3 Meßstellen derselbe Schmelzedruck ermittelt ist. Voraussetzung für die Anwendung dieses Verfahrens sind allerdings Ringspaltströme, bei denen in einem Querschnitt der Ringspaltdüse nahe dem Düsenausgang nahezu konstante Temperaturen in Umfangsrichtung herrschen.According to the invention, this object is achieved by a method the melt pressure distribution in the annular gap in the same cross section of the annular gap nozzle continuously measured at at least 3 points evenly distributed over the circumference and that automatically processed as a function of these in a computing device Measured values of the annular gap nozzle in relation to the fixed nozzle mandrel in the respective required directions is automatically adjusted until at all 3 measuring points the same melt pressure is determined. Prerequisite for using this procedure are, however, annular gap flows in which in a cross section of the annular gap nozzle Near the nozzle outlet almost constant temperatures prevail in the circumferential direction.
Zur Durchführung dieses erfindungsgemäßen Verfahrens ist gemäß weiterer Ausgestaltung der Erfindung eine Vorrichtung vorgesehen, die darin besteht, daß in die Wandung der Ringspaltdüse nahe dem Düsenausgang mindestens 3 handelsübliche druckanaloge Spannungswerte abgebende Membran-Druckaufnehmer eingebaut sind, die Je in einer mit einem Druckübertragungsmittel angefüllten Druckkammer untergebracht sind, die über eine senkrecht zur Schmelze-Fließrichtung angeordnete dünne Bohrung mit dem Fließkanal (Ringspalt) verbunden ist.To carry out this method according to the invention is according to further Embodiment of the invention a device is provided, which consists in that in the wall of the annular gap nozzle near the nozzle outlet at least 3 commercially available Membrane pressure transducers that emit pressure-analogous voltage values are installed Each housed in a pressure chamber filled with a pressure transmission medium are that via a thin bore arranged perpendicular to the melt flow direction is connected to the flow channel (annular gap).
Durch diesen einbau der Druckaufnehmer in die Wandung der Ringspaltdüse werden Strömungen der Schmelzeströmung im Ringspalt vermieden.By installing the pressure transducer in the wall of the annular gap nozzle flows of the melt flow in the annular gap are avoided.
Weitere Einzelheiten sad Vorteile der Erfindung werden anhand der Ausführungsbeispiele näher erörtert. Es zeigen: Fig. 1 den Querschnitt einer Ringapaltduse mit 4 Druck auf nehmern, Fig. 2 den Querschnitt einer Ringspaltduse mit l Druckaufnehmers, Fig, 3 einen Llngsschnitt durch eine Ringspaltdtise nach Fig. 1.Further details sad advantages of the invention are based on the Embodiments discussed in more detail. 1 shows the cross section of a Ringapalt nozzle with 4 pressure transducers, Fig. 2 the cross section of an annular gap nozzle with l pressure transducer, 3 shows a longitudinal section through an annular gap according to FIG. 1.
Die erfindungsgemäße Düse (Fig. 3), die am Ende einer Zuleitung Z angebracht ist, besteht aus einer quer zum Fließkanal (Spalt SP) verstellbaren Düse R und einem innerhalb der Zuleitung Z festangebrachten Dorn D. Gegenüber diesem feststehenden Dorn D ist die Düse D durch automatisch gesteuerte Stellglieder 8, 9 verstellbar, deren Spindel durch einen Motor oder aber auch hydraulisch angetrieben wird. Die erforderliche Druckinessung erfolgt durch Druckaufnehmer, z.B. Al und A3, die mit dem Fließkanal SP Je über eine Kapillare 11 und eine Druckkammer 10 in Verbindung stehen. Vorteilhafterweise ist auch noch eine Schutzheizung 12 vorgesehen, die ein Verstopfen der Kapillare Ii durch Erstarren der Schmelze verhindert.The nozzle according to the invention (Fig. 3), which at the end of a supply line Z. is attached, consists of a nozzle that can be adjusted transversely to the flow channel (gap SP) R and a mandrel D firmly attached within the supply line Z. Opposite this fixed mandrel D is the nozzle D by automatically controlled actuators 8, 9 adjustable, the spindle of which is driven by a motor or hydraulically will. The required pressure measurement is carried out by pressure sensors, e.g. Al and A3, which are connected to the flow channel SP via a capillary 11 and a pressure chamber 10 stay in contact. A protective heater 12 is advantageously also provided, which prevents the capillary Ii from clogging due to the solidification of the melt.
Die Verstellung der Düse R gegenüber dem feststehenden Dorn D kann gemäß den Fig. 1 und 2 in den eingezeichneten Richtungen tx und ty durch die vorgenannten Stellglieder erfolgen. Bei Verwendung von 4 Druckmeßstellen (Fig. 1, 1", "2", fl3, "4n) läuft der Zentriervorgang folgendermaßen ab: Zunächst werden die druckanalogen Spannungswerte der Meßstellen "1" und "3" (mit Hilfe eines Rechenverstärkers) voneinander subtrahiert.The adjustment of the nozzle R relative to the fixed mandrel D can 1 and 2 in the indicated directions tx and ty by the aforementioned Actuators take place. When using 4 pressure measuring points (Fig. 1, 1 "," 2 ", fl3, "4n) the centering process takes place as follows: First, the pressure-analog Voltage values of measuring points "1" and "3" (with the help of a computer amplifier) from one another subtracted.
Dieses Signal wird entsprechend aufbereitet auf ein Stellglied gegeben, welches die Düse bei gleichbleibendem Y-Wert gegenüber dem Dorn solange in +X bzw. -X- Richtung verschiebt, bis das Differenzsignal der Druckmeßstellen 1" und "3" zu Null geworden ist. Dann wird auf die Druckmeßstellen "2" und 4" umgeschaltet, das Differenzsignal gebildet und die Düse nun unter Beibehaltung des zuvor eingestellten X-Wertes solange über das Stellglied in +Y-Richtung verschoben, bis auch dieses Differenzsignal zu Null geworden ist. Die Düse ist dann zentriert.This signal is processed accordingly and sent to an actuator, which the nozzle in + X resp. -X- direction shifts until the differential signal of the pressure measuring points 1 "and" 3 " has become zero. Then it is switched to the pressure measuring points "2" and 4 ", the difference signal is formed and the nozzle now while maintaining the previously set X value is shifted in the + Y direction via the actuator until this too Difference signal has become zero. The nozzle is then centered.
Eine Variante dieses Systems besteht darin, daß statt der Druckaufnehmer "1" und 3" bzw. "2" und 4 Differenzdruckauftehmer verwendet werden, so daß sich die Verwendung eines Rechenverstärkers ertibrigt.A variant of this system is that instead of the pressure transducer "1" and 3 "or" 2 "and 4 differential pressure transducers are used so that the use of a computational amplifier is made.
Bei der Verwendung von Druckmeßstellen, die um 1200 auf dom Umfang versetzt angeordnet sind (Fig. 2), läuft der Zentriervorgang in folgender Weise abs Zunächst werden die druckarlalogen Spannungssignale der Druckmeßstellen "5" und "61' voneinander subtrahiert, es dabei erhaltene Differenzsignal wird aufbereitet auf ein Stellglied gegeben, welches die Diise bei gleichbleibendem Y-Wert solange in der eingezeichneten + bzw. - X-Richtung verschiebt, bis das von "5" und "6" gebildete Differenzsignal zu Null geworden ist.When using pressure measuring points around 1200 on dom scope are arranged offset (Fig. 2), the centering takes place in the following way Section First, the pressure-analog voltage signals from the pressure measuring points "5" and "61 'are subtracted from one another, the difference signal obtained is processed given to an actuator, which the Diise with constant Y-value as long Shifts in the + or - X direction shown until that formed by "5" and "6" Difference signal has become zero.
Dann wird auf die Druckaufnehmer l'6" und 11711 umgeschaltet, deren Differenzsignal gebildet und die Diese gegenüber dem Dorn nun unter Beibehaltung des zuvor eingestellten X-Wertes in Richtung über ein Stellglied verschoben, bis auch dieses Signal zu Null geworden ist. Düse und Dorn liegen dann konzentrisch zueinander.Then a switch is made to the pressure transducers l'6 "and 11711, whose Difference signal is formed and this is now maintained with respect to the mandrel of the previously set X-value in the direction of an actuator until this signal has also become zero. The nozzle and mandrel are then concentric to each other.
Bei einer beispielsweisen Ausführung hatte die Ringspaltdüse die nachstehend genannten Abmessungen: Düsen-Außendurchmesser: 78 mm Düsen-Innendurchmesser: 37 rnm Dorn-Durchmesser: 31,7 mm Meßkanal-Durchmesser: 1,5 mm Länge der Düse: 70 mm Abstand der Meßstellen vom Dilsen-Ende: 20 mmIn an exemplary embodiment, the annular gap nozzle had the following mentioned dimensions: nozzle outer diameter: 78 mm nozzle inner diameter: 37 rnm mandrel diameter: 31.7 mm measuring channel diameter: 1.5 mm length of the nozzle: 70 mm Distance of the measuring points from the Dilsen end: 20 mm
Claims (5)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19772723991 DE2723991A1 (en) | 1977-05-27 | 1977-05-27 | Annular plastic extrusion nozzle control - for uniform pressure distribution with pressure pick=ups and computer |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19772723991 DE2723991A1 (en) | 1977-05-27 | 1977-05-27 | Annular plastic extrusion nozzle control - for uniform pressure distribution with pressure pick=ups and computer |
Publications (1)
Publication Number | Publication Date |
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DE2723991A1 true DE2723991A1 (en) | 1978-11-30 |
Family
ID=6010031
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
DE19772723991 Withdrawn DE2723991A1 (en) | 1977-05-27 | 1977-05-27 | Annular plastic extrusion nozzle control - for uniform pressure distribution with pressure pick=ups and computer |
Country Status (1)
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DE (1) | DE2723991A1 (en) |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4339403A (en) | 1979-11-23 | 1982-07-13 | Windmoller & Holscher | Method of controlling the film thickness at a blown film extruder installation |
FR2529827A1 (en) * | 1982-07-08 | 1984-01-13 | Continental Gummi Werke Ag | EXTRUDING PRESS |
EP0032715B1 (en) * | 1980-01-18 | 1984-04-11 | Wavin B.V. | Centering device for extrusion dies |
US4464318A (en) * | 1980-01-28 | 1984-08-07 | Windmoller & Holscher | Method of controlling the film thickness at a blown film installation |
DE3512097A1 (en) * | 1985-03-29 | 1986-10-09 | Siemens AG, 1000 Berlin und 8000 München | Extruder head for producing hoses |
DE3520836A1 (en) * | 1985-06-11 | 1986-12-11 | Werner St. Margrethen Kempter | Annular die for an extruder, device for centring the annular die and process for producing a pipe or flexible tube by extrusion |
CN112387540A (en) * | 2020-11-17 | 2021-02-23 | 四川庆达实业集团有限公司 | Control system and control method for 3LPE coating of hot bend |
-
1977
- 1977-05-27 DE DE19772723991 patent/DE2723991A1/en not_active Withdrawn
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4339403A (en) | 1979-11-23 | 1982-07-13 | Windmoller & Holscher | Method of controlling the film thickness at a blown film extruder installation |
EP0032715B1 (en) * | 1980-01-18 | 1984-04-11 | Wavin B.V. | Centering device for extrusion dies |
US4464318A (en) * | 1980-01-28 | 1984-08-07 | Windmoller & Holscher | Method of controlling the film thickness at a blown film installation |
FR2529827A1 (en) * | 1982-07-08 | 1984-01-13 | Continental Gummi Werke Ag | EXTRUDING PRESS |
DE3512097A1 (en) * | 1985-03-29 | 1986-10-09 | Siemens AG, 1000 Berlin und 8000 München | Extruder head for producing hoses |
DE3520836A1 (en) * | 1985-06-11 | 1986-12-11 | Werner St. Margrethen Kempter | Annular die for an extruder, device for centring the annular die and process for producing a pipe or flexible tube by extrusion |
CN112387540A (en) * | 2020-11-17 | 2021-02-23 | 四川庆达实业集团有限公司 | Control system and control method for 3LPE coating of hot bend |
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