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EP0688025B1 - Ceramic high voltage insulator - Google Patents

Ceramic high voltage insulator Download PDF

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Publication number
EP0688025B1
EP0688025B1 EP95108162A EP95108162A EP0688025B1 EP 0688025 B1 EP0688025 B1 EP 0688025B1 EP 95108162 A EP95108162 A EP 95108162A EP 95108162 A EP95108162 A EP 95108162A EP 0688025 B1 EP0688025 B1 EP 0688025B1
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EP
European Patent Office
Prior art keywords
voltage insulator
cap
insulator according
thickened
insulator
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EP95108162A
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German (de)
French (fr)
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EP0688025A2 (en
EP0688025A3 (en
Inventor
Martin Kuhl
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Ceramtec GmbH
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Ceramtec GmbH
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Publication of EP0688025A3 publication Critical patent/EP0688025A3/xx
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01BCABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B17/00Insulators or insulating bodies characterised by their form
    • H01B17/14Supporting insulators
    • H01B17/16Fastening of insulators to support, to conductor, or to adjoining insulator
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01BCABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B17/00Insulators or insulating bodies characterised by their form
    • H01B17/38Fittings, e.g. caps; Fastenings therefor
    • H01B17/40Cementless fittings

Definitions

  • High-voltage insulators made of ceramic materials are used mainly in outdoor switchgear and overhead lines. They consist of one elongated insulating body, which is equipped with screens for the Formation of a crawl path that adapts to the atmospheric conditions is. The shields are molded onto the insulator trunk, the thickness of which is determined by the mechanical requirements is determined. At the ends of the insulator or the isolator trunk there are metal caps over which the Power is transmitted from the isolator trunk to further components. High voltage insulators are usually designed to be rotationally symmetrical, if apart from the asymmetry of the caps, for example by individual webs becomes; the isolator caps concentrically surround the ends of the isolator trunk.
  • DE 696 142 teaches an insulator in which metal caps are shrunk on the ground insulator ends are attached. The edge of the caps shows one weakened wall thickness to create compliance.
  • the invention is therefore based on the object to create high voltage insulator made of ceramic material that is precise Has dimensions and maintains them, easy and quick to reinforce and where there are no chemical reactions between the Material components occur. Furthermore, the mechanical strength of the Insulator material with the smallest possible clamping length of the insulator ends in the Metal caps are fully utilized.
  • a rotationally symmetrical high-voltage insulator made of a ceramic material with shrink caps attached to the ends, which is characterized in that the diameter D of the ends is thickened by at least 1.05 times compared to the shank diameter d that the thickened ends cylindrical and frontal to a roughness R a of 0.5 to 30 microns are mechanically processed, that the height H of the cap is greater than the height h of the end and that radial stresses> 40 N / mm 2 in the area of the connection point between the thickened ends and the cap occur.
  • the metal cap With its cap end facing the insulator body, the metal cap can protrude beyond the thickened insulator end and have a stop on its end face which is supported on the end face of the insulator end.
  • a glazed channel and a phase of at least 1.5 mm high, preferably 2-5 mm high, can be provided between the metal cap and the insulator trunk and on the end faces of the insulator ends.
  • the thickened, mechanically processed insulator end and the inner surfaces of the metal caps can have a roughness R a of 0.5-100 ⁇ m, preferably 0.8-30 ⁇ m, particularly preferably 1-10 ⁇ m, and the channel can be filled with a sealant, for example silicone rubber.
  • the metal caps can be provided with flanges which have a groove for receiving a seal.
  • Metal caps can consist of cast aluminum, wrought aluminum alloys, corrosion-resistant steel materials or steel and cast materials with corrosion-protective surface coatings. Porcelain, ceramics containing aluminum oxide, zirconium silicate, cordierite and steatite materials are particularly suitable as ceramic materials.
  • the advantages of the invention are essentially in the simple joining technique, the dimensional accuracy and the reproducibility of the mechanical load values of high-voltage insulators, especially hollow insulators. For the latter has the advantage of easier sealing.
  • Alumina porcelain was used to produce glazed, rotationally symmetrical test specimens 1 with thickened, mechanically machined ends 3, so-called shoulder bars.
  • the rod diameter d was 75 mm, the diameter D of the ends 3 95 mm.
  • the metal caps 2 consisted of a wrought aluminum alloy.
  • the ends 3 of the rods 1 were ground on the circumference and the end face after the fire and had a roughness R a of 1,3-2,5 ⁇ m.
  • the roughness R a of the metal caps 2 in the recess 6 was 1.2-1.5 ⁇ m.
  • the diameter of the recess 6 was smaller than the diameter D of the ends 3; their height H was 65 mm and the height h of the ends 3 60 mm, whereby a groove 7 is formed between the cap and the rod.
  • the metal caps were heated to 250 ° C, then placed on the ends of the rods and cooled to 25 ° C, whereby a metal-ceramic connection is formed by shrinking. Depending on the cap dimensions, a radial stress results in the ceramic, which can be calculated.
  • test specimens were subjected to a tensile test, the tensile forces F z acting in the direction of the arrow. Fracture values between 190 and 230 kN resulted, which corresponds to a tensile strength of the ceramic material of 43-52 N / mm 2 . These test specimens were always broken in the region of the channel 7, ie in the region of the transition from the trunk 8 to the thickened trunk end 3.
  • the test specimens were subjected to a bending strength test, the bending forces F B acting in the direction of the arrow and the relationship between radial stress and bending strength shown in FIG. 3.
  • the strength values between 50 and 100 N / mm 2 come from test specimens, the breaking point of which is in the area of the shoulder 5 of the channel 7.
  • the low strength values ( ⁇ 20 N / mm 2 ) can be attributed to broken windows within the metal cap 2.
  • FIG. 3 shows a clear connection between bending strength and radial stress in the area of the connection point, without scattering, as observed in the prior art.
  • FIG. 3 also shows that radial stresses which are> 40 N / mm 2 are required for the technically interesting bending strengths. Investigations in the temperature range from -25 ° C to + 1 25 ° C, that is, a temperature interval of 150 ° confirmed the reproducibility of the measuring points in Figure 3, whereby a radial tension of 60N / mm 2 was not undercut. It could thus be shown that shrink-fit metal caps on the ends of high-voltage insulators according to the features of the invention can also be used outdoors, where temperature differences in extreme climatic regions of up to 100 ° C. can be expected.
  • the trunk 8 is included molded shields 4 provided.
  • the end 3 of the insulating body has one larger diameter D than the diameter d of the stem 8.
  • the Metal cap 2 preferably made of an aluminum alloy or stainless steel existing, is with radial tension on the ground end 3 of Insulated body arranged.
  • the metal cap 2 can with a circumferential Stop 9 are provided, which in the reinforcement of the insulating body on the End face of the end 3 of the insulating body rests. This way, a precise connection dimension of the isolator reached.
  • the assembly of the metal caps 2 is very simple. The heated metal caps are simply on the ends of the insulator and then cool down in a few seconds until that the isolator can be handled immediately. After about 30 minutes you can the isolator can already be checked mechanically without setting the Metal caps occurs.
  • the roughness of the joining surfaces of the shrink fit is of great importance, since the removal of the cap as a result of mechanical stress does not only depend on the radial tension in the shrink fit but also on the coefficient of friction between the joining surfaces.
  • a roughness R a of 1-10 ⁇ m has been found to be particularly advantageous in the aluminum / porcelain pairing.
  • Also of great importance in the case of hollow insulators is the sealing of components which are fastened to the porcelain hollow insulator. It has been shown that the roughness of the aluminum / porcelain pairing is 1-10 ⁇ m water- and gas-tight, so that seals 10 can also be arranged in a groove 13 in the flange 11 of the metal cap 2 (FIG. 4). However, seals 10 can also be arranged according to FIG. 5 on the end face of the end 3 of the insulating body.
  • the end 3 it is advisable, as shown in FIG. 5, for the end 3 to provide the insulating body with a chamfer 12 of at least 1.5 mm in height, which is an angle of 2-45 degrees, especially 5-30 degrees with the Isolator axis.
  • the glazed channel 7 forms because of its notch effect with high mechanical Stress a predetermined breaking point. Since the location of the predetermined breaking point from Overhang of the cap 2 depends, it is advisable the channel 7 as flat as possible to be designed and provided with a radius on the insulator trunk.

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  • Insulators (AREA)
  • Fixed Capacitors And Capacitor Manufacturing Machines (AREA)
  • Discharge Heating (AREA)
  • Organic Insulating Materials (AREA)
  • Cable Accessories (AREA)
  • Insulating Bodies (AREA)
  • Electrostatic Separation (AREA)
  • Compositions Of Oxide Ceramics (AREA)

Abstract

The invention relates to a high voltage insulator of ceramic material, which includes a longitudinal shank having molded sheds and to whose ends of the shank metal caps are shrink-fitted. The ends of the longitudinal shank are enlarged so that the diameter of the enlarged ends is at least 1.05 times the diameter of the longitudinal shank. The cylindrical surface, and the end face of the enlarged ends of the longitudinal shank are machined.

Description

Hochspannungsisolatoren aus keramischen Werkstoffen finden Verwendung hauptsächlich in Freiluftschaltanlagen und Freileitungen. Sie bestehen aus einem langestreckten Isolierkörper, der mit Schirmen ausgestattet ist, für die Ausbildung eines Kriechweges, der den atmosphärischen Bedingungen angepaßt ist. Die Schirme sind am Isolatorstrunk angeformt, dessen Dicke durch die mechanischen Anforderungen bestimmt ist. An den Enden des Isolierkörpers bzw. des Isolatorstrunkes befinden sich Metallkappen, über die die Kraftübertragung vom Isolatorstrunk zu weiterführenden Bauteilen erfolgt. Hochspannungsisolatoren sind meistens rotationssymmetrisch ausgeführt, wenn von der Asymmetrie der Kappen zum Beispiel durch einzelne Stege abgesehen wird; die Isolatorkappen umgeben konzentrisch die Enden des Isolatorstrunks. Für die Größe der mechanischen Belastbarkeit ist nicht nur der Strunkdurchmesser des Isolators entscheidend, sondern auch die Gestaltung der Strunkenden, die Art der Befestigung der Metallkappen am Strunk und die Gestaltung und der Werkstoff der Metallkappen sowie die Art der mechanischen Beanspruchungen, die prinzipiell Zugkräfte, Druckkräfte, Biegekräfte und Torsionskräfte oder Kombinationen dieser Kräfte sein können. Die Konstruktionen der Metallkappen richten sich daher nach der jeweils vorherrschenden Beanspruchungsart.High-voltage insulators made of ceramic materials are used mainly in outdoor switchgear and overhead lines. They consist of one elongated insulating body, which is equipped with screens for the Formation of a crawl path that adapts to the atmospheric conditions is. The shields are molded onto the insulator trunk, the thickness of which is determined by the mechanical requirements is determined. At the ends of the insulator or the isolator trunk there are metal caps over which the Power is transmitted from the isolator trunk to further components. High voltage insulators are usually designed to be rotationally symmetrical, if apart from the asymmetry of the caps, for example by individual webs becomes; the isolator caps concentrically surround the ends of the isolator trunk. For the size of the mechanical resilience is not only that Punch diameter of the insulator is crucial, but also the design of the Shanking ends, the way the metal caps are attached to the trunk and the Design and the material of the metal caps as well as the type of mechanical Stresses that are principally tensile, compressive, bending and Torsional forces or combinations of these forces can be. The Constructions of the metal caps therefore depend on the prevailing type of stress.

Gemäß A. HECHT, Elektrokeramik 1976, Seiten 144-147; 158/9, 162-177 und 188-191, werden bei den bekannten Hochspannungsisolatoren - voll oder hohl ausgeführt - die Metallkappen auf das zu armierende Isolatorende gestülpt und der Spalt zwischen Isolatorstrunk und Metallkappe mit einem aushärtenden Kittmaterial gefüllt, wie verschiedene Zementsorten, Blei oder Gießharz. Dabei sind die Isolatorkörperenden unterschiedlich gestaltet. So sind die Enden von zugbeanspruchten Langstabisolatoren (Hängeisoiatoren) konisch und glasiert ausgebildet und häufig mit einem Bleiverguß in der Metallkappe befestigt. Bei auf Biegung und/oder Torsion beanspruchten Stützisolatoren werden die Isolierkörper meistens mit zylindrischen Enden versehen. Dabei können die Enden in verschiedener Weise rauh gestaltet sein, z.B. geriffelt, gesplittet oder gewellt. Als Kittwerkstoff wird hauptsächlich Portlandzement verwendet. Die Biegefestigkeit von Stützisolatoren ist stark vom Verhältnis von Kittiefe zu Isolatorstrunkdurchmesser abhängig. Metallkappen für Hänge- und Stützisolatoren bestehen meistens aus verzinktem Gußeisen, weil bei diesen Isolatoren keine großen Genauigkeiten bei den äußeren Abmessungen verlangt werden. Bei hohen Anforderungen an die Genauigkeit der äußeren Abmessungen der Isolatoren bestehen die Metallkappen meistens aus Aluminiumlegierungen, die maschinell genauestens bearbeitet werden müssen und nach der maschinellen Bearbeitung keinen zusätzlichen Korrosionsschutz mehr benötigen. Um die notwendige Präzision der Isolatorenabmessungen während des Kittens der Kappen zu erreichen, muß ein entsprechender Aufwand für die Positionierung der Kappen erbracht werden.According to A. HECHT, Elektrokeramik 1976, pages 144-147; 158/9, 162-177 and 188-191, are at the well-known high-voltage insulators - fully or hollow - put the metal caps on the insulator end to be reinforced and the Gap between insulator trunk and metal cap with a hardening Putty material filled, such as different types of cement, lead or casting resin. Here the insulator body ends are designed differently. So are the ends of long rod insulators (hanging isolators) conical and glazed trained and often fixed with a lead casting in the metal cap. At post insulators that are subjected to bending and / or torsion are used Insulating bodies usually have cylindrical ends. The Rough ends in various ways, e.g. grooved, split or curled. Portland cement is mainly used as the cement material. The Bending strength of post insulators is strongly dependent on the ratio of putty depth to Insulator trunk diameter dependent. Metal caps for hanging and Post insulators are mostly made of galvanized cast iron, because with them Insulators do not require great accuracy in the external dimensions will. For high demands on the accuracy of the external dimensions of the insulators, the metal caps mostly consist of aluminum alloys, which have to be machined very precisely and after the machining no longer require additional corrosion protection. The necessary precision of the isolator dimensions during kiting Reaching the caps requires a corresponding effort for positioning the caps are made.

Nach DE-A-36 43 651 ist bekannt, die Metallkappen auf die Enden von Keramik-Kugelkopfisolatoren aufzuschrumpfen. Danach werden die Komponenten gemeinsam aufgeheizt, gefügt und gemeinsam abgekühlt, damit das keramische Werkstück keinen Schaden nimmt. Diese Art der Fügetechnik ist für Isolatoren sehr aufwendig, da insbesondere Hohlisolatoren Abmessungen im Meterbereich aufweisen können. Hier will die Erfindung Abhilfe schaffen.According to DE-A-36 43 651 it is known that the metal caps on the ends of ceramic ball head insulators shrink. After that, the components heated together, joined and cooled together so that the ceramic Workpiece is not damaged. This type of joining technique is for isolators very complex, because hollow insulators in particular have dimensions in the meter range can have. The invention seeks to remedy this.

DE 696 142 lehrt einen Isolator, bei dem Metallkappen durch Aufschrumpfen auf die geschliffenen Isolatorenden befestigt sind. Der Rand der Kappen zeigt eine geschwächte Wandstärke, um eine Nachgiebigkeit zu erzeugen.DE 696 142 teaches an insulator in which metal caps are shrunk on the ground insulator ends are attached. The edge of the caps shows one weakened wall thickness to create compliance.

Der Erfindung liegt demnach die Aufgabe zugrunde, einen Hochspannungsisolator aus keramischem Werkstoff zu schaffen, der präzise Abmessungen aufweist und sie auch beibehält, einfach und schnell zu armieren ist und bei dem keine chemischen Reaktionen zwischen den Werkstoffkomponeten auftreten. Ferner soll die mechanische Festigkeit des Isolatorwerkstoffs bei möglichst kleiner Einspannlänge der Isolatorenden in die Metallkappen voll ausgenutzt werden. The invention is therefore based on the object To create high voltage insulator made of ceramic material that is precise Has dimensions and maintains them, easy and quick to reinforce and where there are no chemical reactions between the Material components occur. Furthermore, the mechanical strength of the Insulator material with the smallest possible clamping length of the insulator ends in the Metal caps are fully utilized.

Die Aufgabe wird durch einen rotationssymmetrischen Hochspannungsisolator aus einem keramischen Werkstoff mit an den Enden befestigten Schrumpfkappen gelöst, der dadurch gekennzeichnet ist, daß der Durchmesser D der Enden gegenüber dem Strunkdurchmesser d um mindestens das 1,05-fache verdickt ausgeführt ist, daß die verdickten Enden zylindrisch und stirnseitig auf eine Rauhigkeit Ra von 0,5 bis 30 µm mechanisch bearbeitet sind, daß die Höhe H der Kappe größer ist als die Höhe h des Endes und daß Radialspannungen > 40 N/mm2 im Bereich der Verbindungsstelle zwischen den verdickten Enden und der Kappe auftreten.The object is achieved by a rotationally symmetrical high-voltage insulator made of a ceramic material with shrink caps attached to the ends, which is characterized in that the diameter D of the ends is thickened by at least 1.05 times compared to the shank diameter d that the thickened ends cylindrical and frontal to a roughness R a of 0.5 to 30 microns are mechanically processed, that the height H of the cap is greater than the height h of the end and that radial stresses> 40 N / mm 2 in the area of the connection point between the thickened ends and the cap occur.

Die Metallkappe kann mit ihrem dem Isolatorkörper zugewandten Kappenende das verdickte Isolatorende überragen und an ihrer Stirnseite einen Anschlag aufweisen, der sich auf der Stirnseite des Isolatorendes abstützt. Zwischen Metallkappe und Isolatorstrunk kann eine glasierte Rinne und an den Stirnflächen der Isolatorenden eine Phase von mindestens 1,5 mm Höhe, bevorzugt von 2-5mm Höhe, vorgesehen sein. Das verdickte, mechanisch bearbeitete Isolatorende und die Innenflächen der Metallkappen können eine Rauhigkeit Ra von 0,5-100µm, bevorzugt von 0,8-30µm, besonders bevorzugt von 1-10µm aufweisen und die Rinne mit einem Dichtungsmittel, z.B. Silikongummi ausgefüllt sein. Die Metallkappen können mit Flanschen versehen sein, die eine Nut zur Aufnahme einer Dichtung aufweisen. Metallkappen können aus Gußaluminium, Aluminium-Knetlegierungen, korrosionsbeständigen Stahlwerkstoffen oder Stahl- und Gußwerkstoffen mit korrosionsschützenden Oberflächenbeschichtungen bestehen. Als keramische Werkstoffe kommen vor allem Porzellane, aluminiumoxidhaltige Keramik, Zirkonsilicat-, Cordierit- und Steatitwerkstoffe in Betracht.With its cap end facing the insulator body, the metal cap can protrude beyond the thickened insulator end and have a stop on its end face which is supported on the end face of the insulator end. A glazed channel and a phase of at least 1.5 mm high, preferably 2-5 mm high, can be provided between the metal cap and the insulator trunk and on the end faces of the insulator ends. The thickened, mechanically processed insulator end and the inner surfaces of the metal caps can have a roughness R a of 0.5-100 µm, preferably 0.8-30 µm, particularly preferably 1-10 µm, and the channel can be filled with a sealant, for example silicone rubber. The metal caps can be provided with flanges which have a groove for receiving a seal. Metal caps can consist of cast aluminum, wrought aluminum alloys, corrosion-resistant steel materials or steel and cast materials with corrosion-protective surface coatings. Porcelain, ceramics containing aluminum oxide, zirconium silicate, cordierite and steatite materials are particularly suitable as ceramic materials.

Die Vorteile der Erfindung sind im wesentlichen in der einfachen Fügetechnik, der Maßhaltigkeit und der Reproduzierbarkeit der mechanischen Belastungswerte der Hochspannungsisolatoren insbesondere von Hohlisolatoren zu sehen. Für letztere ergibt sich der Vorteil einer einfacheren Abdichtbarkeit.The advantages of the invention are essentially in the simple joining technique, the dimensional accuracy and the reproducibility of the mechanical load values of high-voltage insulators, especially hollow insulators. For the latter has the advantage of easier sealing.

Im Folgenden wird die Erfindung anhand der Figuren näher erläutert.The invention is explained in more detail below with reference to the figures.

Es zeigen

  • Figur 1 einen Prüfling für Zugversuche, teilweise geschnitten;
  • Figur 2 einen Prüfling für Biegeversuche, teilweise geschnitten;
  • Figur 3 den Zusammenhang zwischen Radialspannung und Biegefestigkeit;
  • Figur 4 einen Abschnitt eines hohlen Stützisolators geschnitten und
  • Figur 5 eine Variante zu Figur 4.
  • Show it
  • 1 shows a test specimen for tensile tests, partially cut;
  • Figure 2 shows a test specimen for bending tests, partially cut;
  • Figure 3 shows the relationship between radial stress and bending strength;
  • Figure 4 cut a section of a hollow post insulator and
  • 5 shows a variant of FIG. 4.
  • Aus Tonerdeporzellan wurden mit Glasur versehene rotationssymmetrische Prüflinge 1 mit verdickten, mechanisch bearbeiteten Enden 3, sogenannte Schulterstäbe hergestellt. Der Stabdurchmesser d betrug 75mm, der Durchmesser D der Enden 3 95mm. Die Metallkappen 2 bestanden aus einer Aluminium-Knetlegierung. Die Enden 3 der Stäbe 1 waren am Umfang und stirnseitig nach dem Brand geschliffen und wiesen eine Rauhigkeit Ra von 1,3-2,5µm auf. Die Rauhigkeit Ra der Metallkappen 2 in der Ausnehmung 6 betrug 1,2-1,5µm. Der Durchmesser der Ausnehmung 6 war kleiner als der Durchmesser D der Enden 3; ihre Höhe H betrug 65 mm und die Höhe h der Enden 3 60 mm, wodurch sich eine Rinne 7 zwischen Kappe und Stab ausbildet. Die Metallkappen wurden auf 250°C erwärmt, danach auf die Enden der Stäbe gestülpt und auf 25°C abgekühlt, wodurch sich eine Verbindung Metall-Keramik durch Schrumpfen bildet. Je nach Kappenabmessungen resultiert eine Radialspannung in der Keramik, die berechnet werden kann.Alumina porcelain was used to produce glazed, rotationally symmetrical test specimens 1 with thickened, mechanically machined ends 3, so-called shoulder bars. The rod diameter d was 75 mm, the diameter D of the ends 3 95 mm. The metal caps 2 consisted of a wrought aluminum alloy. The ends 3 of the rods 1 were ground on the circumference and the end face after the fire and had a roughness R a of 1,3-2,5μm. The roughness R a of the metal caps 2 in the recess 6 was 1.2-1.5 μm. The diameter of the recess 6 was smaller than the diameter D of the ends 3; their height H was 65 mm and the height h of the ends 3 60 mm, whereby a groove 7 is formed between the cap and the rod. The metal caps were heated to 250 ° C, then placed on the ends of the rods and cooled to 25 ° C, whereby a metal-ceramic connection is formed by shrinking. Depending on the cap dimensions, a radial stress results in the ceramic, which can be calculated.

    Gemäß Figur 1 wurden die Prüflinge einer Zerreißprüfung unterworfen, wobei die Zugkräfte Fz in Pfeilrichtung angreifen. Es ergaben sich Bruchwerte zwischen 190 und 230 kN, was einer Zugfestigkeit des Keramikwerkstoffes von 43-52 N/mm2 entspricht. Der Bruch dieser Prüflinge erfolgte immer im Bereich der Rinne 7, d.h. im Bereich des Übergangs vom Strunk 8 zum verdickten Strunkende 3.According to FIG. 1, the test specimens were subjected to a tensile test, the tensile forces F z acting in the direction of the arrow. Fracture values between 190 and 230 kN resulted, which corresponds to a tensile strength of the ceramic material of 43-52 N / mm 2 . These test specimens were always broken in the region of the channel 7, ie in the region of the transition from the trunk 8 to the thickened trunk end 3.

    Gemäß Figur 2 wurden die Prüflinge einer Biegefestigkeitsprüfung unterzogen, wobei die Biegekräfte FB in Pfeilrichtung angreifen und der sich in Figur 3 dargestellte Zusammenhang zwischen Radialspannung und Biegefestigkeit ergibt. Die Festigkeitswerte zwischen 50 und 100 N/mm2 stammen von Prüflingen, deren Bruchstelle im Bereich der Schulter 5 der Rinne 7 ist. Die niedrigen Festigkeitswerte (<20 N/mm2) sind auf Scheibenbrüche innerhalb der Metallkappe 2 zurückzuführen.According to FIG. 2, the test specimens were subjected to a bending strength test, the bending forces F B acting in the direction of the arrow and the relationship between radial stress and bending strength shown in FIG. 3. The strength values between 50 and 100 N / mm 2 come from test specimens, the breaking point of which is in the area of the shoulder 5 of the channel 7. The low strength values (<20 N / mm 2 ) can be attributed to broken windows within the metal cap 2.

    Figur 3 zeigt einen eindeutigen Zusammenhang zwischen Biegefestigkeit und Radialspannung im Bereich der Verbindungstelle, ohne daß Streuungen auftraten, wie nach dem Stand der Technik beobachtet. Figur 3 zeigt ferner, daß für die technisch interessanten Biegefestigkeiten Radialspannungen benötigt werden, die >40 N/mm2 sind. Untersuchungen im Temperaturbereich von -25°C bis + 1 25°C , also einem Temperaturintervall von 150° bestätigten die Reproduzierbarkeit der Meßpunkte in Figur 3, wobei eine Radialspannung von 60N/mm2 nicht unterschritten wurde. Damit konnte gezeigt werden, daß aufgeschrumpfte Metallkappen auf die Enden von Hochspannungsisolatoren gemäß den Merkmalen der Erfindung auch im Freien eingesetzt werden können, wo Temperaturdifferenzen in extremen Klimagebieten von bis zu 100°C zu erwarten sind.FIG. 3 shows a clear connection between bending strength and radial stress in the area of the connection point, without scattering, as observed in the prior art. FIG. 3 also shows that radial stresses which are> 40 N / mm 2 are required for the technically interesting bending strengths. Investigations in the temperature range from -25 ° C to + 1 25 ° C, that is, a temperature interval of 150 ° confirmed the reproducibility of the measuring points in Figure 3, whereby a radial tension of 60N / mm 2 was not undercut. It could thus be shown that shrink-fit metal caps on the ends of high-voltage insulators according to the features of the invention can also be used outdoors, where temperature differences in extreme climatic regions of up to 100 ° C. can be expected.

    Bei dem in Figur 4 dargestellten Hohlisolator aus Porzellan ist der Strunk 8 mit angeformten Schirmen 4 versehen. Das Ende 3 des Isolierkörpers weist einen größeren Durchmesser D auf als der Durchmesser d des Strunkes 8 auf. Durch Schleifen der äußeren Umfangfläche des Endes 3 und der Stirnseite des Endes 3 wird die Länge des Isolierkörpers auf ein präzises Maß gebracht. Die Metallkappe 2, vorzugsweise aus einer Aluminiumlegierung oder aus Edelstahl bestehend, ist mit radialer Spannung auf dem geschliffenen Ende 3 des Isolierkörpers angeordnet. Die Metallkappe 2 kann mit einem umlaufenden Anschlag 9 versehen werden, der bei der Armierung des Isolierkörpers auf der Stirnfläche des Endes 3 des Isolierkörpers aufliegt. Auf diese Weise wird ein präzises Anschlußmaß des Isolators erreicht. Die Montage der Metallkappen 2 ist sehr einfach. Die aufgeheizten Metallkappen werden einfach auf die Enden des Isolierkörpers aufgesteckt und kühlen dann in einigen Sekunden soweit ab, daß der Isolator sofort gehandhabt werden kann. Nach etwa 30 Minuten kann der Isolator bereits mechanisch geprüft werden, ohne daß ein Setzen der Metallkappen auftritt. In the case of the porcelain hollow insulator shown in FIG. 4, the trunk 8 is included molded shields 4 provided. The end 3 of the insulating body has one larger diameter D than the diameter d of the stem 8. By Grinding the outer peripheral surface of the end 3 and the end face of the end 3 the length of the insulating body is brought to a precise level. The Metal cap 2, preferably made of an aluminum alloy or stainless steel existing, is with radial tension on the ground end 3 of Insulated body arranged. The metal cap 2 can with a circumferential Stop 9 are provided, which in the reinforcement of the insulating body on the End face of the end 3 of the insulating body rests. This way, a precise connection dimension of the isolator reached. The assembly of the metal caps 2 is very simple. The heated metal caps are simply on the ends of the insulator and then cool down in a few seconds until that the isolator can be handled immediately. After about 30 minutes you can the isolator can already be checked mechanically without setting the Metal caps occurs.

    Von großer Bedeutung sind die Rauhigkeiten der Fügeflächen des Schrumpfsitzes, da das Abziehen der Kappe in Folge mechanischer Beanspruchung nicht nur von der Radialspannung im Schrumpfsitz abhängt, sondern auch vom Reibbeiwert zwischen den Fügeflächen. Als besonders vorteilhaft hat sich eine Rauhigkeit Ra von 1-10µm bei der Paarung Aluminium/Porzellan herausgestellt. Von großer Bedeutung bei Hohlisolatoren ist auch die Abdichtung zu Bauteilen, die an dem Hohlisolator aus Porzellan befestigt werden. Es hat sich gezeigt, daß Rauhigkeiten der Paarung Aluminium/Porzellan von 1-10µm wasser- und gasdicht sind, so daß Dichtungen 10 auch in einer Nut 13 im Flansch 11 der Metallkappe 2 angeordnet werden können (Figur 4). Dichtungen 10 können jedoch auch gemäß Figur 5 auf der Stirnseite des Endes 3 des Isolierkörpers angeordnet werden.The roughness of the joining surfaces of the shrink fit is of great importance, since the removal of the cap as a result of mechanical stress does not only depend on the radial tension in the shrink fit but also on the coefficient of friction between the joining surfaces. A roughness R a of 1-10 μm has been found to be particularly advantageous in the aluminum / porcelain pairing. Also of great importance in the case of hollow insulators is the sealing of components which are fastened to the porcelain hollow insulator. It has been shown that the roughness of the aluminum / porcelain pairing is 1-10 μm water- and gas-tight, so that seals 10 can also be arranged in a groove 13 in the flange 11 of the metal cap 2 (FIG. 4). However, seals 10 can also be arranged according to FIG. 5 on the end face of the end 3 of the insulating body.

    Für den Fügevorgang ist es zweckmäßig wie in Figur 5 dargestellt, das Ende 3 des Isolierkörpers mit einer Fase 12 von mindestens 1,5 mm Höhe zu versehen, die einen Winkel von 2-45 Grad, insbesondere von 5-30 Grad mit der Isolatorachse einschließt.For the joining process, it is advisable, as shown in FIG. 5, for the end 3 to provide the insulating body with a chamfer 12 of at least 1.5 mm in height, which is an angle of 2-45 degrees, especially 5-30 degrees with the Isolator axis.

    Die eingehenden Untersuchungen der Schrumpfverbindung mit dem Isolatorende haben gezeigt, daß unter allen Umständen jegliche Bewegung zwischen dem Isolator und der Metallkappe vermieden werden muß. Um diese Bedingung auch für den Bereich zu erfüllen, wo der Ort der höchsten mechanischen Beanspruchung für den Isolierwerkstoff liegt, nämlich im Übergangsbereich Ende 3 - Strunk 8, ist es zweckmäßig, die Höhe H der Kappe 2 größer zu wählen als die Höhe h des Isolierkörperendes 3. Die sich dabei bildende Rinne 7 kann zur Vermeidung von Wasserlachenbildung mit einem Einkomponentensilikonkautschuk ausgefüllt werden. Silikonkautschuke auf Acetoxy-Essigsäurebasis haften hervorragend auf Aluminium und glasiertem Porzellan.The detailed investigations of the shrink connection with the insulator end have shown that under all circumstances any movement between the Insulator and the metal cap must be avoided. To this condition too to meet for the area where the place of the highest mechanical The stress on the insulating material lies in the end transition area 3 - Strunk 8, it is appropriate to choose the height H of the cap 2 larger than the height h of the insulating body end 3. The groove 7 that is formed can be used for Avoiding water puddles with one One-component silicone rubber can be filled. Silicone rubbers Acetoxy-acetic acid base adhere well to aluminum and glazed Porcelain.

    Die glasierte Rinne 7 bildet wegen ihrer Kerbwirkung bei hoher mechanischer Beanspruchung eine Sollbruchstelle. Da die Lage der Sollbruchstelle vom Überstand der Kappe 2 abhängt, ist es zweckmäßig die Rinne 7 möglichst flach zu gestalten und mit einem Radius am Isolatorstrunk zu versehen.The glazed channel 7 forms because of its notch effect with high mechanical Stress a predetermined breaking point. Since the location of the predetermined breaking point from Overhang of the cap 2 depends, it is advisable the channel 7 as flat as possible to be designed and provided with a radius on the insulator trunk.

    Die Erfindung wurde am Beispiel des Hohlisolators näher erläutert, weil sie hier am vorteilhaftesten anwendbar ist. Selbstverständlich können Hochspannungsisolatoren gemäß der Erfindung auch als Vollkörper-Stützisolatoren oder als Hängeisolatoren ausgeführt werden. Andere Anwendungen der Erfindung bei Bauteilen höchster Präzision, z.B. bei Schalt- und Betätigungsstangen für elektrische Hochspannungseinrichtungen, sind möglich.The invention was explained in more detail using the example of the hollow insulator because it is here is most advantageously applicable. Of course you can High-voltage insulators according to the invention also as full-body support insulators or as suspension isolators. Other Applications of the invention in high precision components, e.g. with switching and actuating rods for high voltage electrical devices possible.

    Claims (9)

    1. Rotationally symmetrical high-voltage insulator of ceramics material, consisting of a core (8) having integrally moulded sheds (4), to the ends (3) of which core metal caps (2) are secured by means of a shrink fit, characterised in that the diameter (D) of the ends (3) is made at least 1.05 times thicker than the core diameter (d), the thickened ends (3) are mechanically machined cylindrically and on their end faces to a roughness Ra of from 0.5 to 30 µm, the height (H) of the cap (2) is larger than the height (h) of the end (3), and radial stresses > 40 N/mm2 occur in the region of the joint between the thickened ends (3) and the cap (2).
    2. High-voltage insulator according to claim 1, characterised in that with its inner end on the insulating body the metal cap (2) extends beyond the thickened insulating body end (3) .
    3. High-voltage insulator according to claim 1 or 2, characterised in that on the end face of the caps there is provided a stop member (9) which is supported on the end face of the end (3).
    4. High-voltage insulator according to claim 1 or 2, characterised in that a glazed groove (7) is provided between metal cap (2) and insulator core (8).
    5. High-voltage insulator according to claim 1, 2 or 4, characterised in that a bevel (12) having a height of at least 1.5 mm, preferably of 2-5 mm, is provided at the end faces of the ends (3).
    6. High-voltage insulator according to claims 1, 2, 4 or 5, characterised in that the thickened insulator ends (3) have a roughness Ra of from 1-10 µm.
    7. High-voltage insulator according to claims 4, 5 or 6, characterised in that the groove (7) between cap (2) and insulator core (8) is filled with a sealing agent.
    8. High-voltage insulator according to claims 1 to 7, characterised in that the metal cap (2) is provided with a flange (11) which has a groove (13) for receiving a seal (10).
    9. High-voltage insulator according to claims 1 to 8, characterised in that the metal caps (2) consist of cast aluminium, aluminium/wrought alloy, corrosion-resistant steel materials or steel materials and cast materials having corrosion-resistant surface coatings.
    EP95108162A 1994-06-17 1995-05-29 Ceramic high voltage insulator Expired - Lifetime EP0688025B1 (en)

    Applications Claiming Priority (2)

    Application Number Priority Date Filing Date Title
    DE4421343 1994-06-17
    DE4421343A DE4421343A1 (en) 1994-06-17 1994-06-17 High voltage ceramic insulator

    Publications (3)

    Publication Number Publication Date
    EP0688025A2 EP0688025A2 (en) 1995-12-20
    EP0688025A3 EP0688025A3 (en) 1996-01-10
    EP0688025B1 true EP0688025B1 (en) 1998-08-05

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    Application Number Title Priority Date Filing Date
    EP95108162A Expired - Lifetime EP0688025B1 (en) 1994-06-17 1995-05-29 Ceramic high voltage insulator

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    US (1) US5977487A (en)
    EP (1) EP0688025B1 (en)
    JP (1) JPH087684A (en)
    AT (1) ATE169422T1 (en)
    BR (1) BR9502815A (en)
    CA (1) CA2152029A1 (en)
    DE (2) DE4421343A1 (en)
    ZA (1) ZA954979B (en)

    Families Citing this family (15)

    * Cited by examiner, † Cited by third party
    Publication number Priority date Publication date Assignee Title
    FR2765385B1 (en) * 1997-06-26 2003-12-05 Gec Alsthom T & D Sa COMPOSITE INSULATOR HANGER
    IT1299049B1 (en) * 1998-04-08 2000-02-07 Abb Research Ltd ISOLATOR ESPECIALLY FOR ELECTRICAL TRANSMISSION AND DISTRIBUTION LINES, HAVING IMPROVED RESISTANCE TO THE
    US6229094B1 (en) * 1998-11-16 2001-05-08 Hubbell Incorporated Torque prevailing crimped insulator fitting
    CA2375608C (en) * 2000-03-29 2004-08-03 Ngk Insulators, Ltd. Method of producing polymer insulator and end processing apparatus utilized for this method
    US6367774B1 (en) 2000-04-19 2002-04-09 Flowserve Corporation Element having ceramic insert and high-strength element-to-shaft connection for use in a valve
    US6522256B2 (en) * 2000-05-16 2003-02-18 Southern Electric Equipment Hybrid current and voltage sensing system
    JP4376174B2 (en) * 2004-12-01 2009-12-02 日本碍子株式会社 Polymer SP insulator
    EP1995739B1 (en) * 2007-05-23 2011-08-17 ABB Technology AG HV isolator and cooling element for this HV isolator
    WO2013104983A1 (en) * 2012-01-13 2013-07-18 Trench Limited Method of manufacture of porcelain insulator structures and method and assembly for affixing metal flanges to porcelain insulators
    EP2637180A1 (en) * 2012-03-06 2013-09-11 ABB Technology Ltd A post insulator
    CN102689745B (en) * 2012-05-14 2015-05-13 平高集团有限公司 Package structure and packaging method of post insulators
    CN105914674B (en) * 2016-06-07 2018-04-03 浙江华蕴海洋工程技术服务有限公司 A kind of cable protection pipe
    CN111599543B (en) * 2020-06-29 2021-07-23 江西省萍乡电瓷电器厂 A height-adjustable insulator
    CN115497697B (en) * 2022-10-21 2025-03-14 江苏南瓷绝缘子股份有限公司 A corrosion-resistant suspension insulator for ultra-high voltage transmission lines
    WO2025068744A1 (en) * 2023-09-27 2025-04-03 Asasoft (Canada) Inc Galvanized line insulators

    Family Cites Families (9)

    * Cited by examiner, † Cited by third party
    Publication number Priority date Publication date Assignee Title
    US1031453A (en) * 1910-09-27 1912-07-02 Clouth Rhein Gummiwarenfabrik Insulator.
    US1769262A (en) * 1926-06-30 1930-07-01 Condit Electrical Mfg Corp Oil-filled bushing
    DE696142C (en) * 1936-05-24 1940-09-14 Porzellanfabrik Kahla Insulator, especially solid core insulator, with metal caps fastened through
    US2924644A (en) * 1953-04-20 1960-02-09 Cox John Edward Electrical insulator links
    DE1130024B (en) * 1957-11-15 1962-05-24 Siemens Ag Attachment of metal fittings to ceramic insulators
    GB1009571A (en) * 1961-03-01 1965-11-10 Pilkington Brothers Ltd Improvements in or relating to electrical insulators
    GB8312892D0 (en) * 1983-05-11 1983-06-15 Raychem Ltd Electrical insulator
    DE3643651A1 (en) * 1986-12-17 1988-06-30 Steuer Mess Regel Armaturen Gm Process for the production of a shrink joint between at least two workpieces comprising materials with different expansion coefficients
    JP2664616B2 (en) * 1993-03-25 1997-10-15 日本碍子株式会社 Airtight structure of non-ceramic insulator

    Non-Patent Citations (1)

    * Cited by examiner, † Cited by third party
    Title
    ELEKTROKERAMIK, A. HECHT,1976,SEITEN 144-147,158/9,162-177, 188-191. *

    Also Published As

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    US5977487A (en) 1999-11-02
    JPH087684A (en) 1996-01-12
    EP0688025A2 (en) 1995-12-20
    EP0688025A3 (en) 1996-01-10
    ZA954979B (en) 1996-02-21
    DE4421343A1 (en) 1995-12-21
    ATE169422T1 (en) 1998-08-15
    CA2152029A1 (en) 1995-12-18
    BR9502815A (en) 1996-02-06
    DE59503054D1 (en) 1998-09-10

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