Abstract: A method of measuring variation in the elongation of a very long element of small transverse dimensions and made of magnetizable material, optionally covered by non-magnetic material, and running between a lower elongation zone and a higher elongation zone, or vice versa, said method consisting in periodically magnetically marking the elongate element simultaneously at two points spaced apart by a predetermined distance therealong in a first one of said zones, and then in detecting the instants at which said magnetic marks pass at least one point situated in the other one of said zones.

Abstract: A sealed connection between an undersea coaxial line cable and a length of coaxial access cable connected to a repeater; the line cable comprising an axial conductor (11), insulation (12), a return path (13) and an outer sheath (14A); the access cable comprising an axial conductor (15), insulation, metal braiding (20A, B) forming a return path, and an outer sheath (14B); and the connection comprising a conical conductive metal connection part (16) for inter-connecting the axial conductors, a surface moulded layer of insulating thermoplastic material (17), a conductive connector (18) for interconnecting the return paths of the line cable and the access cable, and a reconstituted sheathing between the line cable and the access cable, wherein said conductive connector for inter-connecting the return paths comprises an aluminum flared tube fitted tightly over the surface-moulded insulation, with a layer of graft polyolefin or adhesive ionomer tape wound helically around the surface moulding being sandwiched in be

Abstract: A device for preventing damage to a submarine cable at the point where it leaves an equipment casing during passage round the cable drum and over the davit, and consisting of a chocking member (5) on each side of the casing (2) surrounding the cable (1) from its outlet from the casing to a point of contact of the cable with the drum (3), said chocking member being in the form of a body of revolution about the cable axis of generally pear-shaped configuration when unstressed and having a swollen part (6) at the casing end, said chocking member occupying all the space between the cable (1) and the drum (3) when the cable is wound on the drum, the swollen part of the chocking member when unstressed having a radius at least equal to the distance (d) between the cable and the drum at the outlet from the casing. The chocking member may be a sleeve of a strong and flexible material; it may also consist of a stack of elementary chocking members.

Abstract: An optical fibre cable includes a generally cylindrical elongate central support structure with helical grooves formed around its periphery. The grooves (2) are partially filled with the compound (3) which is viscous at cable operation temperature. Said support structure (1) is then cooled to reversibly harden said compound (3). Optical fibres (4) are then layed in the grooves over the compound in its hard state. Lastly the grooves are topped up with viscous compound.

Abstract: An optical fibre cable comprises a support structure having helical grooves around its periphery. Optical fibres are laid in the grooves. Said fibre-containing grooves (2) are then partially untwisted in the direction of the arrow (4), thereby lengthening the pitch of the grooves and hence lengthening the fibres relative to the grooves.

Abstract: Apparatus for tracking the paths of helical grooves at the periphery of a longitudinal core driven in translation. The apparatus comprises two disks (11, 12) fitted onto said core, said disks being connected together by metal wires (13) forming a spring which presses on the grooves (21, 22) to track their apparent rotation when said core (2) moves in translation.Application to laying optical fibres on a grooved carrier core.

Abstract: The coaxial sub-marine telephone cable employs a central conductor which is formed by a compound twisted core of high tensile steel wires and of aluminum-based wires which are encased in a longitudinally welded copper tube that is applied tightly around the twisted core. The aluminum-based wire has high tensile strength, high breaking elongation and good electrical conductivity. The crushing of the aluminum based wires by the steel wires under the effect of radial pressures exerting on the core through sizing dyes while being manufactured is minimized and avoided by arranging the steel wires in contact with each other under radial compression so that they interact as an arch or vault.

Abstract: An undersea optical fiber cable with a protective metal casing around the optical fibers 1. The casing includes a stranded assembly 3 of high-tensile metal wires of polygonal cross-section 3A forming an arch structure. The side (4) which is turned towards the axis of the cable is shorter than the outwardly-turned side 5, and intermediate sides 6 touch or interlock. A metal outer tube 7 is formed by skelping a tape to produce a cylinder and then welding the longitudinal edges thereof. The metal casing is filled with a liquid 4A whose density is close to that of water and whose viscosity is close to that of glycerine. The overall density of the cable is slightly higher than that of water.

Abstract: A method of butt-joining metal tapes coated on one or both sides with a film of thermoplastic polymer material.The film is detached from an end portion of each tape (1A 1B) by immersion in a solvent at its boiling point. The detached film is removed and the ends of the two tapes welded together. A film (17, 18) of high-density polyethylene and ionomer resin is applied to the stripped area and bonded thereto by the application of heat and pressure. Device for implementation of the method.

Abstract: An assembly for fixing an undersea telecommunications cable with a central strength member (1) but no metal armouring to the housing of a repeater (2). It includes a funnel-shaped conical part (3) with a flared mouth piece, a neck 3A whose inside diameter is equal to the diameter of the cable. Said conical part is fixed to the housing of the repeater. An elongate elastomer sleeve surrounds the end of the cable up to the inner zone of the neck of said conical part and has an outside diameter which tapers gradually towards its end distant from said mouth piece. An elongate shell (8) is made of stratified glass and resin material, said material surrounding the flared end of the mouth piece of the conical part and said sleeve. An outer sleeve (9) made of braid of high tensile strength extends around the periphery of said shell, and an elevator cover (10) surrounds the aforementioned parts. Application to cables which are to be submerged to great depths.