Abstract: A method of joining tubes with friction welding includes the steps of aligning end walls of tubes to be welded, introducing an intermediate tube segment between the tubes, and bringing the tube end walls together against opposing end walls of the tube segment to put the end walls under axial compressive stress at a friction ramp-up pressure. The method further includes rotating the intermediate tube segment about a tube segment longitudinal axis in at least one direction, increasing the axial compressive friction stress to a forging pressure in order to heat the end parts of the tube and the intermediate tube segment, and increasing the axial compressive friction stress to a forging pressure, thus joining the tubes and the tube segment. The tube segments have a tube wall made of a material resistant to hydrogen embrittlement.

Abstract: A metallic water barrier sheath for power cables for submarine or land applications is provided where the water barrier sheath comprises a metallic layer made of tin or a tin alloy.

Abstract: A reinforced water barrier over a joint between power cables is suited for subsea cables having different water barrier/sheathing designs. The reinforced water barrier has an intermediate water barrier made of lead or a lead alloy which stretches over the joint and is attached to the underlaying water barriers of the joined cables, and which is reinforced by being coated with a layer of polyethylene based adhesive followed by a layer of polymeric outer sheathing. The adhesive layer and the layer of polymeric outer sheathing are thermally set by a heat treatment.

Abstract: Power cables are provided having a joint with a metallic water barrier and, in particular, metallic water barrier materials for cable joints for use in high voltage cables for both land and submarine applications.

Abstract: A reinforced water barrier over a joint between power cables is suited for subsea cables having different water barrier/sheathing designs. The reinforced water barrier comprises an intermediate water barrier made of lead or a lead alloy which stretches over the joint and is attached to the underlaying water barriers of the joined cables, and which is reinforced by being coated with a layer of polyethylene based adhesive followed by a layer of polymeric outer sheathing. The adhesive layer and the layer of polymeric outer sheathing are thermally set by a heat treatment.

Abstract: A water barrier for encapsulating a cable core has a layer of metal foil having a thickness of t1, and a single layer of a polyethylene-based polymer having a thickness of t2. The ratio t2:t1 is at least seven and the single layer of a polyethylene-based polymer has been deposited onto the metal foil by extrusion at an extrusion temperature of at least 150° C. with the metal foil preheated to a temperature of at least 130° C.

Abstract: The present invention relates to a laminate water barrier which is capable of conducting capacitive currents radially out of the cable thus avoiding breakdown due to induced voltage gradients, comprising a laminate structure comprising a metal foil having a lower and an upper surface area, a first layer of a thermoplastic polymer laid onto and covering the lower surface of the layer of metal foil except for a longitudinal uncovered surface area of the layer of metal foil, and a second layer of thermo-plastic polymer laid onto and covering the upper surface of the layer of metal foil except for a longitudinal uncovered surface area of the layer of metal foil, and wherein the laminate structure is wrapped around the cable core such that the first uncovered surface area of the metal foil faces the cable core and the second uncovered surface area of the metal foil faces away from the laminate structure, and the laminate structure is thermally joined by a heat treatment.

Abstract: A lead-free water barrier suited for dynamical submarine high voltage power cables has a water barrier including a laminate structure. The laminate structure has a metal foil having a lower and an upper surface area. A first layer of a thermoplastic semiconducting polymer is laid onto the first adhesive layer, and a second layer of a thermoplastic semiconducting polymer is laid onto the second adhesive layer. The laminate structure is thermally joined by a heat treatment.