Insulator for a medium- or high-voltage gas-insulated switchgear

1. An insulator for a gas-insulated device, comprising an injection-molded insulator disc and a conductor, wherein

the insulator disc comprises a first circumferential surface, a second circumferential surface disposed radially outwards from the first circumferential surface, and a web portion connecting the first circumferential surface and the second circumferential surface,

characterized in that the web portion comprises a wave structure, the web portion having an inner wave profile at the first circumferential surface and an outer wave profile at the second circumferential surface, wherein the inner wave profile and the outer wave profile each have a radius of curvature of 2 mm or more and 10,000 mm or less

wherein the inner wave profile has a first number of cycles (n i ) and the outer wave profile has a second number of cycles (n o ) which is more than the first number of cycles (n i ).

2. The insulator according to claim 1 , wherein the web portion has a circumferential radius of curvature of 2 mm or more and 10,000 mm or less.

3. The insulator according to claim 1 , wherein the web portion has a substantially constant thickness in the direction perpendicular to an upper surface and/or a lower surface of the web portion, wherein substantially constant thickness comprises a thickness that remains within a +/−10% tolerance between a thickest portion of a web portion and a thinnest portion of the web portion.

4. The insulator according to claim 1 , wherein the inner wave profile has a first amplitude (A i ) and the outer wave profile has a second amplitude (A o ) which is less than the first amplitude (A i ).

5. The insulator according to claim 1 , wherein the second number of cycles (n o ) is an integer multiple of the first number of cycles (n i ).

6. The insulator according to claim 5 , wherein each peak of the inner wave profile is radially aligned with a respective peak of the outer wave profile or a respective trough of the outer wave profile.

7. The insulator according to claim 1 , wherein the insulator disc is directly injection molded on an outer surface of the conductor.

8. The insulator according to claim 1 , wherein the web portion further comprises stiffeners connecting the first circumferential surface to the second circumferential surface.

9. The insulator according to claim 8 , wherein a number of stiffeners is equal to double the first number of cycles (n i ).

10. The insulator according to claim 1 , wherein the insulator disc comprises a thermoplastic comprising one of the group containing TPU, TPE, epoxy and PUR.

11. The insulator according to claim 1 , wherein the insulator disc has at least one radiused edge between the web portion and the first circumferential surface and/or between the web portion and the second circumferential surface.

12. A gas-insulated switchgear configured for medium-voltage or high-voltage, comprising at least one insulator according to claim 1 .

13. The gas-insulated switchgear according to claim 12 further configured for switching a medium voltage or a high voltage.

14. A method for the production of an insulator according to claim 1 , said method comprising:

providing a mold for injection molding of an insulator disc, the insulator disc comprising an inner portion having a central opening;

arranging a conductor in a cavity of the mold;

injecting a material into the mold to form the insulator disc such that the conductor is positioned inside the central opening and the inner portion and the conductor are directly or indirectly fastened together; and

removing the insulator from the mold.