Abstract: A recoverable article comprises a recoverable fabric, means for rendering the fabric impervious, and a shaped liner. The assembly can be used to form a pressure resistant splice case for telecommunications cables.

Abstract: An article comprises two areas of heat-recoverable woven fabric which are joined together along a line by means of a mechanical joining arrangement, such as stitches, staples or a stitched or stapled zip, which penetrates the fabric. The direction of crimp of the area penetrated is substantially perpendicular to the line of the join, or the two areas have substantially parallel directions of crimp.

Abstract: A cross-linked polymeric composition comprises a linear, low density ethylene homo- or copolymer which, prior to cross-linking is characterized by (a) a density at 25.degree. C. of 0.940 gm/cm.sup.3 or less (b) a linearity expressed in terms of pendant methyl groups per 10.sup.3 carbon atoms of the polymeric chain of less than 30 with a substantial absence of long chain branches, and preferably (c) no more than 5 branches greater in length than C.sub.8. The cross-linked polymeric composition is particularly suitable for the production of dimensionally recoverable articles, for the production of insulation material, for the production of semi-conductive or conductive polymers for use in electrical heating materials, and for the production of semi-permeable membranes.

Abstract: A strip of hollow heat-recoverable articles formed side-by-side by tear welding two lengths of polymeric material together at intervals so that individual articles may be torn off. A preferred method of making the strip involves cross-linking after the tear welding, heating the strip, and inflating the hollow articles to render them heat-recoverable by introducing pressure via an interconnecting passage formed for that purpose during the tear welding.

Abstract: First and second bodies of heat recoverable polymeric material are fusion bonded together with their directions of recovery at an angle to each other, the bond preferably being cross-linked after bonding to enable the resulting article better to withstand the recovery forces encountered in use. The invention is especially useful for making wraparound tubular enclosures for "T"'s and bends which enclosures in use will recover radially about two tubular axes.

Abstract: A process for the production of a marker sleeve assembly which comprises deforming a substantially non-cross-linked web of polymeric material at a temperature below the crystalline melting point or softening point of the material to render the web heat-recoverable, fusing together parts of the web or parts of the web and at least one other polymeric web to define a plurality of radially inwardly heat-recoverable marker sleeves, disposed in side-by-side relationship and preferably separable and subsequently cross-linking the resulting assembly.

Abstract: Novel polymeric compositions having non-linear resistance characteristics, together with electrical equipment comprising such compositions. Any polymer may be used; the polymer contains substantial proportions of certain particulate fillers of a given structure, for example the perovskite and spinel structures.

Abstract: A dimensionally recoverable polymeric article for enclosing at least part of an elongate object such as a cable or connector has a surface at least part of which has an electrically conductive layer, preferably a metal layer, adhering thereto to provide a screen against electromagnetic interference. The surface of the article carrying the layer is profiled in the form of a number of grooves that extend substantially perpendicularly to the direction of recovery of the article to allow the article to recover with substantially no change in dimension of the surface in the direction of recovery.

Abstract: A cable breakout article (78) which is formed of a polymeric material and which is preferably heat-recoverable comprises a body portion and at least two tubes or outlet portions (91 to 94) leading from apertures in the body portion. The length and flexibility of the tubes (91 to 94) is such that at least one of them can be bent away from the other(s) to allow operations such as heat recovery to be carried out on an end portion of one of the tubes in isolation from the others.Preferably one or more of the tubes (95) is corrugated at least near its end adjacent to the body portion (78) so as to assist bending.

Abstract: An assembly for marking an elongate object, for example a wire or cable, comprises a flexible heat-recoverable marker strip (1) having one surface which is capable of receiving printed characters, and being supported on a rigid carrier strip to prevent premature recovery of the marker strip when heated, for example when heated to render the printed characters indelible. The assembly is characterized in that the other surface of the marker strip (1) is at least partly coated with a heat-activatable adhesive (2), and is provided with one or more areas of pressure-sensitive or contact adhesive (3) capable at least temporarily of securing the marker strip in position about the object after separation from the carrier strip, and preferably also capable of supporting the marker strip on the carrier strip before separation of the marker strip therefrom.

Abstract: A dimensionally recoverable body, which is preferably heat-recoverable, has a body wall which is provided with a plurality of locking elements that are engageable with each other, or are engageable with corresponding elements located on a separate partition, to furcate the body into a plurality of channels.The body may be used for enclosing branch-offs in electrical cables in order to protect the enclosed branch-off from the environment.

Abstract: Terminations and splices in high voltage electrical cable can be shielded by shrinking over the termination or splice a heat recoverable hollow article which comprises a heat-shrinkable outer sleeve whose outer surface is anti-tracking at voltages of 2.5 KV and at least part of whose inner surface has a layer thereon which is solid at room temperature and which has electrical stress-grading character.

Abstract: A polymeric article, at least part of which is dimensionally-recoverable, preferably heat-recoverable, has, bonded to the surface of a dimensionally-recoverable portion thereof, a pliant, adhesive-receptive polymeric film which is soft at the temperature at which the dimensionally-recoverable portion is recovered, and which is substantially non-curable at ambient temperatures. The polymeric film is preferably based on a film-forming chlorinated resin or a film forming silane.The articles may be recovered over objects such as electrical equipment to provide electrical insulation and may be bonded to the object or other article with an adhesive without the necessity of any special surface treatment immediately before bonding.

Abstract: A process for the production of a heat shrinkable article which comprises forming bonds between regions of at least two superimposed lengths of polymeric material to produce a bonded article so disposed that the desired direction of heat shrinkability lies along the length of the bonded article, cross-linking the bonded article and the bonds between the said lengths of polymeric material, heating the bonded article, stretching the bonded article longitudinally and cooling it (which may comprise allowing it to cool naturally in the stretched condition) to render the articles heat shrinkable. Pneumatic or other methods of expansion may be used in addition to the stretching to render hollow articles heat-shrinkable, the combination of stretching and another such method being advantageous in achieving high expansion ratios while maintaining a reasonable degree of symmetry in the finished hollow recoverable articles.

Abstract: The substantial change in modulus with temperature of certain materials, especially memory metals, is used to make a novel connector by forcing a band made from such a material in its low modulus state up an external tapered portion of a tubular coupling member so as to deform the band which remains in position about the coupling member. To make a connection one or more substrates is(are) positioned inside the tubular coupling member and the band is brought to its high modulus state whereupon it contracts and deforms the tubular coupling member and forces it into firm connection with the substrate.

Abstract: A device for forming a mechanical and/or electrical connection between a plurality of elongate objects 1, 2, for example bus bars in electrical switchgear, comprises one or more inserts or shell members 9, 10 that can be positioned about the ends of the objects to form a tubular assembly extending between the objects.One or more memory metal drivers in the form of bands or rings 7, 8 may be provided for retaining the tubular assembly in position and forcing the shell portions against the objects 1, 2 so that a good electrical contact is formed. Preferably an annular protuberance or contact surface 12 is provided on the internal surface of the shell members 9, 10 at each end thereof, and are preferably arranged so as to be partly flattened as the bonds or rings 7, 8 contract, thereby increasing the contact area between the shell members and the objects 1, 2.

Abstract: A process for the manufacture of a dimensionally recoverable article comprises forming a plurality of separate component parts thereof, joining the component parts together to form the article, cross-linking the polymeric material from which the parts are formed after they have been joined together, and then expanding the article.The process enables dimensionally recoverable articles of complex shape to be manufactured by high speed moulding processes or extrusion processes without the need for curing of the article during formation thereof.

Abstract: A wrap-around device for enclosing an elongate object comprises a cover having two opposed edge portions and that can be interlocked to retain them together. At least one of the edge portions, and preferably both the edge portions, are provided with a protuberance, which extend along the edge portions and engage the opposed edge portion that may be caused if the edge portions are subjected to a tensile force tending to separate them, for example as may be caused if the device and enclosed object is bent.Preferably at least one of the edge portions is provided with a layer of adhesive to prevent moisture ingress between the edge portions.

Abstract: A wrap-around device for enclosing at least part of an elongate substrate such as a pipe comprises a dimensionally-recoverable cover, preferably a dimensionally heat-recoverable cover, having an adhesive closure arrangement comprising two closure portions which can be brought into abutment to form an adhesive bond but which, when pulled in a direction away from each other after the adhesive bond has been formed, will change in configuration to form a lap joint.The device according to the invention enables an adhesive wrap-around device to be installed about a substrate in a simple manner without the possibility of misalignment of the closure portions.

Abstract: A dimensionally-recoverable article which is particularly suitable for the manufacture or repair of cable harnesses has a dimensionally-recoverable portion formed from a material comprising a crosslinked segmented polyether-ester block copolymer and an adhesive portion comprising a polyether-ester random copolymer which portions are bonded together to form a single integral structure.