CH571267A5

CH571267A5 - Glass fibre-reinforced plastics tension rod for insulator - anchored in end fitting of insulator for transmission of tensile forces to all glass fibres

Info

Publication number: CH571267A5
Application number: CH1428274A
Authority: CH
Original assignee: Klaey Hans
Priority date: 1974-10-23
Filing date: 1974-10-23
Publication date: 1975-12-31

Abstract

Insulator tension rod is made of glass-fibre-reinforced plastics, pref. a thermosetting plastic material, and its end is anchored in an end fitting of the insulator by heating the end until the plastics bond between fibres is weakened; the end is then conically expanded in all directions and anchored in the fitting by filling the gaps with a curable synthetic resin. The drawing shows a view of the expanded tension rod with conical pin, with two variants of the end fitting, on the left conically adapted to the rod, and on the right cylindrical with cementing grooves.

Description

  

  
 



   Als Zugelement von Isolatoren aus Kunstharz wird vorteilhaft ein Glasfiberstab verwendet, in welchem die Glasfasern in Längsrichtung verlaufend die Zugkräfte übernehmen und durch Kunstharz gebunden sind. Die Überleitung der Zugkräfte von den Endarmaturen der Isolatoren auf die Glasfiberstäbe soll so ausgeführt werden, dass die Zugfestigkeit des Glasfiberstabes voll ausgenützt werden kann. Das ist dann der Fall, wenn jede Glasfaser gleichem Zuge ausgesetzt wird. Der Glasfiberstab hat üblicherweise zylindrische Enden. Eine bekannte Fassung dieser zylindrischen Enden geschieht mit aufgepressten Metallhülsen. Dabei werden die äussersten Fasern des Glasfiberstabes durch Reibung mit der Metallhülse verbunden und bei Zug die Kraft durch die Bindung mit Kunstharz auf die inneren Fasern übertragen.



  Um eine gleichmässige Lastverteilung auf alle Fasern zu erlangen, muss die Metallhülse genügend lang sein, d. h. ein Mehrfaches des Stabdurchmessers betragen. Eine andere Ausführungsart besteht darin, dass das zylindrische Ende des Stabes durch einen Keil aufgespalten und in eine entsprechende Armatur eingekittet wird. Bei Zug werden in dieser Ausführung nur die äussersten Fasern belastet.



   Die ideale Lastverteilung ist dann erreicht, wenn alle Glasfasern in der Armatur gleichmässig gezogen werden.



  Die Erfindung betrifft demnach ein Verfahren zum Herstellen einer zugfesten Verankerung des Endes eines faserarmierten Kunststoffstabes in einer Befestigungsarmatur. Als Bindungsharz für die Glasfiberstäbe wird heute ein Duroplast verwendet, d. i. ein Harz, welches durch Mischung mehrerer Komponenten oder durch Erhitzen erhärtet. Dieser Duroplast verliert beim Erhitzen über eine jedem Harz eigene Temperatur - in der Fachsprache Martenstemperatur - den mechanischen Zusammenhang.



   In diesem erwärmten Zustand kann das Ende des Glasfiberstabes durch geeignete Werkzeuge auf eine konische Form ausgeweitet werden, ohne die einzelnen Glasfasern zu zerstören. Die Erwärmung der Enden kann durch Eintauchen in ein heisses Bad - Salz oder Legierung - geschehen.



  Die Eintauchdauer, bis das Stabende bis ins Innere auf die notwendige Temperatur durchgewärmt ist, wird durch Versuche ermittelt. Ein Ausführungsbeispiel ist auf beiliegender Zeichnung gezeigt.



   Fig. 1 zeigt einen Längsschnitt in 2 Varianten der Armatur, links in konischer Anpassung an den Glasfiberstab, rechts zylindrisch mit Kittrillen, und
Fig. 2 eine Ansicht von oben auf den ausgeweiteten Glasfiberstab mit 1 konischer Stift, 2 ausgeweiteter Glasfiberstab, 3 Ausgussmasse, 4 Armatur.



   Der Glasfiberstab wird in der Regel in zylindrischer Form hergestellt und auf die gewünsche Länge abgeschnitten. Die beiden zylindrischen Enden können nun nach der beschriebenen Weise in konische Köpfe ausgeweitet und so zur Kittung in passende Armaturen umgeformt werden. Der innere konische Hohlraum wird mit einem konischen Stift 1 fixiert, so dass sich das konische Ende bei Zug nicht wieder schliessen kann. Das so gebildete konische Stabende wird in eine passende Armatur gesteckt und die Hohlräume und Spalten mit einem erhärtenden Kunstharz ausgegossen und damit in der Armatur verankert.

 

   PATENTANSPRUCH



   Verfahren zur Herstellung einer zugfesten Verankerung des Endes eines faserarmierten Kunststoffstabes in einer Befestigungsarmatur, dadurch gekennzeichnet, dass das Stabende bis zur Schwächung der Kunststoffbindung zwischen den Armierungsfasern erwärmt und hierauf nach allen Richtungen konisch ausgeweitet und in der Armatur durch Ausgiessen der Spalten mit einem erhärtenden Kunstharz verankert wird.

**WARNUNG** Ende DESC Feld konnte Anfang CLMS uberlappen**.



   



  
 



   A fiberglass rod is advantageously used as the tension element of insulators made of synthetic resin, in which the glass fibers, running in the longitudinal direction, take over the tensile forces and are bound by synthetic resin. The transfer of the tensile forces from the end fittings of the insulators to the fiberglass rods should be carried out in such a way that the tensile strength of the fiberglass rod can be fully utilized. This is the case when each fiber is subjected to the same pull. The fiberglass rod usually has cylindrical ends. A known setting of these cylindrical ends is done with pressed-on metal sleeves. The outermost fibers of the fiberglass rod are connected to the metal sleeve by friction and, when pulled, the force is transferred to the inner fibers through the bond with synthetic resin.



  In order to achieve an even load distribution on all fibers, the metal sleeve must be long enough, i.e. H. be a multiple of the rod diameter. Another embodiment consists in that the cylindrical end of the rod is split open by a wedge and cemented into a corresponding fitting. In this version, only the outermost fibers are loaded when there is tension.



   The ideal load distribution is achieved when all the glass fibers in the fitting are pulled evenly.



  The invention accordingly relates to a method for producing a tensile anchoring of the end of a fiber-reinforced plastic rod in a fastening fitting. A thermoset is used today as the binding resin for the fiberglass rods, i.e. i. a resin that hardens by mixing several components or by heating. This thermoset loses its mechanical connection when heated above each resin's own temperature - in technical terms Marten temperature.



   In this heated state, the end of the glass fiber rod can be expanded to a conical shape using suitable tools without destroying the individual glass fibers. The ends can be heated by immersion in a hot bath - salt or alloy.



  The duration of immersion until the end of the rod is warmed up to the required temperature inside is determined through tests. An exemplary embodiment is shown in the accompanying drawing.



   Fig. 1 shows a longitudinal section in 2 variants of the fitting, on the left in a conical adaptation to the fiberglass rod, on the right cylindrical with kit grooves, and
2 shows a view from above of the expanded fiberglass rod with 1 conical pin, 2 expanded fiberglass rod, 3 pouring compound, 4 fitting.



   The fiberglass rod is usually manufactured in a cylindrical shape and cut to the desired length. The two cylindrical ends can now be expanded into conical heads in the manner described and thus shaped into suitable fittings for cementing. The inner conical cavity is fixed with a conical pin 1 so that the conical end cannot close again when pulled. The conical rod end thus formed is inserted into a suitable fitting and the cavities and gaps are filled with a hardening synthetic resin and thus anchored in the fitting.

 

   PATENT CLAIM



   A method for producing a tensile anchoring of the end of a fiber-reinforced plastic rod in a fastening fitting, characterized in that the rod end is heated until the plastic bond between the reinforcing fibers is weakened and then expanded conically in all directions and anchored in the fitting by pouring the gaps with a hardening synthetic resin becomes.

** WARNING ** End of DESC field could overlap beginning of CLMS **.

Claims

** WARNING ** Beginning of CLMS field could overlap end of DESC **.

A fiberglass rod is advantageously used as the tension element of insulators made of synthetic resin, in which the glass fibers, running in the longitudinal direction, take over the tensile forces and are bound by synthetic resin. The transfer of the tensile forces from the end fittings of the insulators to the fiberglass rods should be carried out in such a way that the tensile strength of the fiberglass rod can be fully utilized. This is the case when each fiber is subjected to the same pull. The fiberglass rod usually has cylindrical ends. A known setting of these cylindrical ends is done with pressed-on metal sleeves. The outermost fibers of the fiberglass rod are connected to the metal sleeve by friction and, when pulled, the force is transferred to the inner fibers through the bond with synthetic resin.

In order to achieve an even load distribution on all fibers, the metal sleeve must be long enough, i.e. H. be a multiple of the rod diameter. Another embodiment consists in that the cylindrical end of the rod is split open by a wedge and cemented into a corresponding fitting. In this version, only the outermost fibers are loaded when there is tension.

The ideal load distribution is achieved when all the glass fibers in the fitting are pulled evenly.

The invention accordingly relates to a method for producing a tensile anchoring of the end of a fiber-reinforced plastic rod in a fastening fitting. A thermoset is used today as the binding resin for the fiberglass rods, i.e. i. a resin that hardens by mixing several components or by heating. This thermoset loses its mechanical connection when heated above each resin's own temperature - in technical terms Marten temperature.

In this heated state, the end of the glass fiber rod can be expanded to a conical shape using suitable tools without destroying the individual glass fibers. The ends can be heated by immersion in a hot bath - salt or alloy.

The duration of immersion until the end of the rod is warmed up to the required temperature inside is determined through tests. An exemplary embodiment is shown in the accompanying drawing.

Fig. 1 shows a longitudinal section in 2 variants of the fitting, on the left in a conical adaptation to the fiberglass rod, on the right cylindrical with kit grooves, and 2 shows a view from above of the expanded fiberglass rod with 1 conical pin, 2 expanded fiberglass rod, 3 pouring compound, 4 fitting.

The fiberglass rod is usually manufactured in a cylindrical shape and cut to the desired length. The two cylindrical ends can now be expanded into conical heads in the manner described and thus shaped into suitable fittings for cementing. The inner conical cavity is fixed with a conical pin 1 so that the conical end cannot close again when pulled. The conical rod end thus formed is inserted into a suitable fitting and the cavities and gaps are filled with a hardening synthetic resin and thus anchored in the fitting.

PATENT CLAIM

A method for producing a tensile anchoring of the end of a fiber-reinforced plastic rod in a fastening fitting, characterized in that the rod end is heated until the plastic bond between the reinforcing fibers is weakened and then expanded conically in all directions and anchored in the fitting by pouring the gaps with a hardening synthetic resin becomes.