Hitachi Energy Ltd

Abb Technology Ltd

Hitachi Energy Switzerland Ag

Abb Power Grids Switzerland Ag

Anders Holmberg

Magnus U Henriksson

Bengt Asplund

Anders C Johansson

Jonas Persson

Mattias Lundborg

Anna Brorsson

Stefan Hortlund

Andre Johansson

Anders Johansson

Magnus Henriksson

The present disclosure relates to a fibre reinforced polymer (FRP) tube, the tube comprising a plurality of concentric layers of an FRP material forming a shell of the tube. At least one blind threaded longitudinal bolt hole is provided from a transverse end surface of the shell. The bolt hole extends in at least three of the plurality of layers, a middle layer encompassing a plane passing through a center of the bolt hole, an inner layer encompassing a plane of an innermost extent of the bolt hole, and an outer layer encompassing a plane of an outermost extent of the bolt hole. The fibre filament of each of the inner and outer layers has been wound at a first angle to the longitudinal axis and the fibre filament of the middle layer has been wound at a second angle to the longitudinal axis.

Fibre reinforced polymer tube

Shatter protection for a high voltage apparatus with a ceramic insulator includes at least one electrically insulating tube including a plurality of holes going through an envelope surface. The electrically insulating tube has a diameter such that there is a minimum distance between the tube and the ceramic insulator when arranged concentrically. A method for producing a shatter protection includes winding a first helix shape of the electrically insulating fiber composite material at a first pitch such that there is a first gap between the winding turns, and winding a second helix shape of the electrically insulating fiber composite material onto the first helix shape in the opposite direction and at a second pitch, such that there is a second gap between the winding turns. Thereby forming a first electrically insulating tube with holes formed by the first and second gap between the winding turns.

Shatter protection

An insulator for separating two objects with different electrical potential, the insulator including an insulating body enclosing a first volume for housing a gas, the body being provided with an opening, and a sealing arrangement arranged to seal the opening in the body and including a first gas-tight sealing element for sealing the opening and provided with a first closable opening, and a second gas-tight sealing element for sealing the opening, and arranged inside the first sealing element so that the first and second sealing elements define a second volume significantly smaller than the first volume. The second sealing element is provided with a second closable opening which in cooperation with the first closable opening enable control of the gas pressure in the first volume. Methods for leakage detection of the insulator are also disclosed.

Method of testing the integrity of a second seal of an electrical insulator

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Öjebyn, Sweden

Anders Holmberg