Abstract: An overvoltage protector in an apparatus having two moving parts (1,5). The parts are connected via a bearing (2,3,4), one part being stationary in relation to a substructure (13) at an electrical ground potential. The moving part (5) can be subjected to a voltage and the stationary part (1) is electrically connected to the grounded substructure. For preventing current from passing through the bearing between the parts, an electrical insulator (6,7) is provided in the current path which can occur through the bearing as a result of different potentials of the parts. The moving part (5) has a ring (9) spaced from a ring (8) connected to electrical ground such that a spark discharge gap (10) is formed between the parts. The bearings (2,3,4) are protected against current flow by the electrical insulator (6,7) up to a given voltage threshold.

Abstract: An electrical cable of the self-floating type for use in marine environments is provided with elements for taking up mechanical tractive forces. The electrical conductors of the cable are surrounded by an inner friction layer with a low friction coefficient. Around this layer a force equalizing layer of metallic material is provided and this layer is surrounded by a tube of plastic material showing a number of circumferentially situated grooves. An outer friction layer of the same material as the inner friction layer surrounds the hollow strands and the whole system together with the elements for taking up the tractive forces is embedded by a cable mantle of rubber-like plastic material.

Abstract: Laying tool for laying of submarine cable in a sea-bottom trench. The tool comprises a drag unit and a pulling tube joined by a cardanic suspension and drawn by a vessel for use under variable sea and bottom conditions. The cable is laid out from the vessel through the pulling tube, a canal in the drag unit, and, finally, into a sea-bottom trench formed by a ploughing device on the drag unit. This unit is constructed so that the cable is forced down onto the bottom of the trench even if the unit is not operating in a proper position due to a rough sea-bottom. Moreover, the drag unit is constructed so that all material turned up from the sea-bottom is pushed aside from the trench and the ploughing device. The laying tool is also provided with floating tanks adjusted so that the drag unit without cable will float but with cable it will sink. The tanks may be filled with both water and air to facilitate submergence and refloating of the drag unit.