Abstract: Heat-recoverable articles, especially heat-shrinkable tubular articles, having an open end are formed so that the section adjacent said open end has a lower recovery ratio than a section adjacent thereto, thereby substantially reducing the risk of splitting when the degree of recovery is high or in applications where a high degree of unrecovered strain remains after recovery about a substrate such as a supply line. A preferred article is a tubular cap which has an open end section having a first expansion ratio, an intermediate section having a second expansion ratio and a closed end section having a third expansion ratio, the second expansion ratio being greater than the first and third expansion ratios. Such a cap may be employed to seal a conduit against ingress of moisture and other contaminants. When a supply line is subsequently to be passed through the conduit the closed end may be removed and the article shrunk to grip the supply line.

Abstract: A dimensionally heat recoverable article carrying a thermoplastic polymeric material and a heat-softenable adhesive of smaller thickness and lower softening or melting point than the polymeric material is used to encapsulate objects such as joints in cables. The heat-softenable adhesive allows low installation temperature while the polymeric material allows excellent cycling performance to be maintained. The article may be in the form of a wrap-around sleeve.

Abstract: An assembly for enclosing a telecommunication cable splice comprising a wraparound sleeve having longitudinal edges which can be brought together and secured by for example a metal channel. A seal is made between these edges by an internal sealing member which bridges the abutting edges of the sleeve and is urged into contact with the sleeve by expansive urging means between the sealing member and underlying cable splice. The urging means is preferably a foam strip.

Abstract: A heat-recoverable polymeric sheet is coated with a solid sheet of heat-activatable sealant by heating the sheet preferably to a temperature above the crystalline melt point of the polymer, applying, preferably by means of a roller, the sealant sheet to the heated polymer sheet while the polymer sheet is at a temperature capable of activating the sealant so as to adhere it to the polymer sheet. The polymer sheet may be flame-brushed after heating and before application of the sheet of sealant. The technique is particularly useful for sheets intended as wrap-around sleeves for use as enclosures, and which thus have closure rails adjacent opposing longitudinal edges thereof.

Abstract: Insulated pipes are generally bared of insulation at their ends in order to make joints, for example welds, between the pipes. A reinsulating method and assembly is provided for the bared joints, wherein a support comprising a coiled member, for example a helical coil, is positioned around the pipe, a recoverable cover recovered into engagement with the support, and thermally insulating material introduced between the cover and the pipe. The invention is suitable for straight, T, and bent joints.

Abstract: The present invention relates to improved liner constructions, and accordingly provides a cable sleeve liner capable in use of being wrapped around a cable splice and preferably having sufficient rigidity to provide an inner support for a heat-recoverable sleeve to be shrunk thereover, the liner comprising a laminate having at least one layer of fibrous sheet material and a metal layer which is substantially impermeable to moisture vapor and has one of its major surfaces facing away from all fibrous sheet layers which may be present. Preferably the fibrous layer(s) is or are arranged between the metal layer and a microperforated first layer of flexible polymeric film material which is permeable to gases or vapors generated within the laminate during recovery of the sleeve.

Abstract: An article for forming a cable block or for enclosing a cable splice comprises a recoverable driver sleeve and a particulate heat-activatable adhesive temporarily restrained adjacent an inner surface of the sleeve.

Abstract: A cable splice, branchout or termination has a heat recovered member (30) around one or more cable portions (33) extending out of an end of the member (30). The cable portion (33) is protected from physical damage and heat by placing around it individually a metal foil member (1), preferably aluminium of thickness 150-250 microns. The metal foil member is preferably coated with a hot melt adhesive (2) and a mastic (5) at distinct locations. A pressure sensitive adhesive (4) may also be provided to help secure the foil member (1) around the cable portion (33) before recovery of the outer member (30). Apertures (44) may be provided in the foil member (1) to allow passage therethrough of hot melt adhesive provided on the inner surface of the recoverable member (30).

Abstract: A branch-off of at least two substrates leaving an end of a recovered sleeve is effected using a heat activatable sealant, and a thermally conductive member which has a fin-shaped protruberance by means of which heat can be conducted into the crutch region between the substrates to activate the sealant. The thermally conductive member can also function to urge together circumferentially spaced portions of the sleeve to define conduits for the substrates. This urging function can be supplemented or carried out totally by a separate clip.

Abstract: An assembly for sealing and protection of cable splices comprising a recoverable, preferably heat-recoverable outer sleeve 5 surrounding a cable or other body 1; a thermoplastic support layer 7 surrounding the body 1 and within the sleeve 5; and a heat barrier layer, preferably foamed, between the support 7 and the sleeve 5, to prevent thermal deformation of the support 7 during heat recovery of the sleeve or during other heat treatment 5.

Abstract: A wrap-around sleeve for enclosing a cable join has opposing edge portions which can be held together to maintain the sleeve in a wrapped configuration. An adhesive coated flap lies under the edge portions to form a seal between them. When the enclosure is to be re-entered, a central part of the sleeve is cut away, and a new sleeve installed to bridge the butts of the old sleeve which are allowed to remain on the cable. In order to avoid leak paths between the edge portions of the remaining butts, adhesive from the flap is allowed to flow between the edge portions on original installation. This is achieved by providing localized separation between the original edge portions.

Abstract: A heat-recoverable sleeve for enclosing splices or joints in pressurized cables or supply lines is given increased resistance to peeling away from the cable or line by insertion of auxiliary means, preferably a U- or V-shaped flexible strip, which may be heat-recoverable, between the sleeve and the cable or supply line. The ends of the strip are preferably closed and are preferably overlapped and bonded to each other when the strip is placed around the cable or supply line. A release foil may be positioned inside the U- or V-shape of the strip to resist bonding together of the opposed arms thereof, and the foil may carry adhesive to bond it to one of the arms and may protrude beyond the ends of the arms so that the foil adhesive can help to locate the strip on the cable or supply line.

Abstract: A thermochromic composition suitable for coating heat-recoverable materials for cable enclosures. The composition contains an organic material which melts and decomposes at a certain temperature by trapping the decomposition products in the composition.

Abstract: A re-enterable assembly for protecting and sealing a junction between conduits, comprising a split tube and support means for positioning at each end of the tube, one on each side of the junction. The support means has apertures to provide channels for the conduits, and in one embodiment, is extended about the conduits to within the cavity about the junction to provide a seal that improves with an increase in pressure within the cavity.

Abstract: A clamping member for forming a branch-off seal between a recoverable sleeve and more than one substrate extending from an end of the sleeve, comprises at least two interengageable parts that define channels. The parts are assembled on the end of the sleeve such that the clamping member defines ducts for the substrates. Use of a clamping member having interengageable parts, rather than an integral member, makes fixing at the end of the sleeve easier.

Abstract: A branch-off of at least two substrates leaving an end of a recovered sleeve is effected using a heat activatable sealant, and a thermally conductive member which has a fin-shaped protruberance by means of which heat can be conducted into the crutch region between the substrates to activate the sealant. The thermally conductive member can also function to urge together circumferentially spaced portions of the sleeve to define conduits for the substrates. This urging function can be supplemented or carried out totally by a separate clip.

Abstract: A heat-recoverable sleeve for enclosing splices or joints in pressurized cables or supply lines is given increased resistance to peeling away from the cable or line by insertion of auxiliary means, preferably a U- or V-shaped flexible strip, which may be heat-recoverable, between the sleeve and the cable or supply line. The ends of the strip are preferably closed and are preferably overlapped and bonded to each other when the strip is placed around the cable or supply line. A release foil may be positioned inside the U- or V-shape of the strip to resist bonding together of the opposed arms thereof, and the foil may carry adhesive to bond it to one of the arms and may protrude beyond the ends of the arms so that the foil adhesive can help to locate the strip on the cable or supply line.

Abstract: A branch-off seal between a heat-recoverable sleeve, such as a tubular or wrap-around sleeve made from cross-linked polymeric material, and two or more substrates such as electrical cables is effected by using one or more clips the outer legs of which are positioned over the outer surface of the sleeve so as to form as appropriate number of conduits and applying heat to cause the sleeve to shrink about the substrates positioned within the conduits. The preferred clips are formed as a trident, the central leg of which extends into the heat-recoverable sleeve and is provided with a layer of a hot-melt adhesive or another sealant so as to enhance the seal formed at the branch-off.

Abstract: The present invention relates to improved liner constructions, and accordingly provides a cable sleeve liner capable in use of being wrapped around a cable splice and preferably having sufficient rigidity to provide an inner support for a heat-recoverable sleeve to be shrunk thereover, the liner comprising a laminate having at least one layer of fibrous sheet material and a metal layer which is substantially impermeable to moisture vapor and has one of its major surfaces facing away from all fibrous sheet layers which may be present. Preferably the fibrous layer(s) is or are arranged between the metal layer and a microperforated first layer of flexible polymeric film material which is permeable to gases or vapors generated within the laminate during recovery of the sleeve.

Abstract: A bracing surround which comprises a heat-recoverable especially a heat-shrinkable, sleeve provided with a reinforcing member which does not prevent recovery of the sleeve but which is capable, when in the configuration held when the sleeve is recovered, of resisting forces tending to return it to the configuration held when the sleeve is in its recoverable configuration. The surround is used to enclose substrates, e.g., pressurized conduit junctions, that are subject to expansion in use.