Abstract: A method for continuously vulcanizing hoses which comprises two steps: microwave vulcanization; and conventional vulcanization by heat conduction through a heating medium. A layer of heat-resistant synthetic resin which has a melting point higher than the vulcanizing temperature is provided over the outer periphery of a rubber hose in a uniform thickness. This layer is in close contact with the hose but not adherent thereto. After the resin layer is cooled and hardened, the rubber hose is heated and cured in a microwave vulcanizing tank before being subjected to vulcanization by heat conduction through a heating medium in an ordinary vulcanizing tank. After completion of vulcanization, the layer of synthetic resin is peeled off and removed.

Abstract: Combined apparatus for performing the processes to which a rubber tube formed on a metal core must necessarily be subjected to after having been vulcanized comprises a bed constituted by a series of conveyor belts disposed in longitudinal sequence in a horizontal plane, onto which the tubes are individually placed after vulcanization. Along one side of the bed a carriage carrying a spool can be moved with the spool being driven to rotate by a slipping motor. At the two ends of the bed there are positioned header having forks for attachment to the cores on which the tubes are formed. By rotating the spool and simultaneously moving the carriage it is possible to unwrap and recover bindings from tubes of any diameter tidily, while by fixing one end of the metal core to one of the said headers and operating the said conveyor belts, the of finished tube can be released from the associated core.

Abstract: A process for continuously producing pipe by coating a particulate material with a gas curable resin, compacting the coated particulate material in an annular space, treating the compacted, coated particulate material with a curing gas to form a pipe having a porous wall structure, impregnating the porous walls of the pipe with an asphalt or resinous material, and, optionally, winding a reinforcing filament binder around the pipe.

Abstract: A flexible hose having a braided spiral reinforcement layers having one wire braid member which remains uncrimped during braiding and a second braid member which is composed of a relatively flexible, high tenacity material which is crimped or deformed around the wire braid member at each contact point in the braided-spiral layer. The hose may be made using a flexible mandrel technique to produce a light weight hose having improved flexibility for use in high pressure applications such as in hydraulic system components.

Abstract: A flexible hose having a novel braided reinforcement layer wherein one braid member is a relatively stiff, uncrimped monofilament and the second braid member is a flexible textile material which is crimped around the stiff monofilament at each contact point in the braided spiral layer. The braided spiral imparts improved crush and kink resistance to the hose structure. The method of manufacture employs no mandrel and produces a balanced tension braided hose which may be preferably cured by open steam techniques.

Abstract: The present invention relates to an improved cooling chamber for the manufacture of high-pressure reinforced hose. Hose to be treated is passed through a tubular passageway in the cooling chamber where it is contacted with a cryogenic fluid. A portion of the cryogenic fluid is passively recycled via a recycle loop to provide further cooling within the tubular passageway. An end seal is attached to one end of the cooling chamber to prevent moisture build-up and freezing inside the chamber.

Abstract: The present invention relates to an improved cooling process for the manufacture of high-pressure reinforced hose. Hose to be treated is passed through a cooling chamber where it is contacted with a cryogenic fluid which totally flashes to a cold gas upon contact with the hose. A portion of the cold gas is passively recycled to provide further cooling. One end of the cooling chamber is sealed to prevent moisture build-up and freezing inside the chamber.

Abstract: A flexible hose has a thermoplastic core tube, a reinforcing layer surrounding the core tube, an elastomeric sheath surrounding and bonded to the reinforcing layer, and a plastic fiber protection layer surrounding and adhering to the sheath. The hose can be made by applying a layer of viscous cement to the reinforcing layer applied around the core tube, wrapping the viscous cement layer, with an overlapping seam, with a calendered layer stock of elastomeric material, and applying an abrasion protection layer around the elastomeric material. The hose is self-curing at ambient temperature and can be made on conventional hose manufacturing equipment.

Abstract: A method of manufacture of pressure hose is described. An uncured tubular structure including one or more sub-units each having a radially inner tubular layer of uncured elastomer and an outer tubular layer of filamentary reinforcing elements is subjected to fluid pressure in its bore. The fluid pressure forces uncured elastomer material into the interstices of the filamentary layer of each sub-unit and consolidates the uncured structure. A cover layer of elastomer material is thereafter applied and the covered structure is cured into an integral hose.

Abstract: A method of making a composite container comprising a hollow, molded, plastic body and a liner formed of relatively thin, flexible sheet material, such as paperboard or plastic film, surrounding and reinforcing the body side wall.

Abstract: A high voltage coaxial cable wherein a corona-free configuration is produced by applying a room temperature-curable silicone elastomeric material under pressure to the outer surface of the cable braid so that the material is forced between the voids of the braid and adheres to the primary insulation material at the insulation/braid interface.

Abstract: A method and apparatus is provided for manufacturing a reinforced elastomeric hose. Other reinforced hoses are prepared in individual stations for particular parts of the reinforced hose consequently requiring large amounts of manufacturing floor space. Still other hoses that are made while utilizing small amounts of floor space do not provide a high strength braided reinforcement member. A reinforced hose (10) is produced by continuously braiding a tubular reinforcement member (16) on a mandrel (50), progressively removing the reinforcement member from the mandrel (50), and at approximately the same axial location extruding a liner (26) and cover (28) onto the reinforcement member (16) adjacent the mandrel (50). After leaving the extruders (33,34), the formed hose (10) is pulled at a linear rate faster than the hose (10) is being produced in order to change the braid angle of the braided reinforcement member (16) to a predetermined smaller braid angle.

Abstract: The present invention comprises an improved apparatus and method for fabricating coaxial cable. Coaxial cable fabricated in accordance with the present invention comprises an inner conductive member encased in an annular electrical insulator, an outer electrically conducting sheath being annularly disposed about the insulator providing electrical shielding for the inner conductor. The improved apparatus and method for fabricating coaxial cable directs flattened malleable conductive strands for braiding the outer electrical sheath. The individual strands forming the braided sheath are each disposed about a cylindrical bobbin and fed about a pair of directing pins and positioners which position the flattened sheath material for entry into a braiding cone. Denatured alcohol lubricates the braiding cone during the braiding process in order to provide for uniform distribution of the braided sheath about the electrical conductor and insulator.

Abstract: Extruded reinforced hoses are useful in fluid systems which operate at high pressures. Other reinforced hoses are prepared in individual stations for particular parts of the reinforced hose consequently requiring large amounts of manufacturing floor space. Still other processes require extruding a hose on a mandrel and subsequently applying a fabric reinforcement member. In these processes, the length of the hose is limited by the length of the mandrel. The present apparatus produces an extruded reinforced hose (10) by braiding a metal reinforcement member (16) on a mandrel (42) and extruding a liner (21) and cover (22) at approximately the same location as the member (16) leaves the mandrel (42). The formed hose (10) is pulled at a linear rate faster than the hose (10) is being produced in order to change the braid angle of the braided member (16) to a predetermined selected braid angle and holding for subsequent curing.

Abstract: There is disclosed a process for manufacturing large-diameter, large-length hoses. The process is characterized by applying the elements required for building the hoses onto a flexible foundation lead through an advancing or through an advancing and rotating movement of same while conveying the hose along a curved course, the track of the course having the shape of a preferably closed curve, and by vulcanizing the built up hose preferably by applying electric energy.

Abstract: In an apparatus for manufacturing reinforced hoses, a reinforced layer forming device is arranged concentric with material efflux port of an outer tube extruder and an inner tube extruder so that inner tube formation, the reinforcing layer formation and the outer tube extruding can be performed continuously and nearly at the same time on a torpedo projected beyond the top end of an inner die (2) of the inner tube extruder (1). In order to obtain the reinforcing layer of uniform spiral structure stably, a spiral device (21) as a reinforcing layer forming device has an inner spinner (25) and an outer spinner (26), each having conical frustum form, and top end portions of the inner and outer spinners are provided with a plurality of thread holes (G1, G2) and inserted in a gap between the intermediate die (12) and the inner die (2), and the inner and outer spinners can be rotated integrally with inner and outer bobbin carriers respectively.

Abstract: An improved method for producing a reinforced hose. A tubular core is extruded and then heated in a microwave oven to at least partially cure the core. While the core is still hot, a powdered hot-melt adhesive is electrostatically coated onto the core and forms a fusion bond with the core. The coated core is cooled, a reinforcement is applied to the core, an optional outer coating is applied and then the composite is heated to finish curing of the hose and to melt the adhesive to bond the reinforcement to the core.

Abstract: The invention relates to a method and an apparatus for the manufacture of high-pressure hose composed of a plastic core and a plurality of layers of helically wound plastic-resisting members formed in particular of wires of high tensile strength which are rewound in a rewinding device from a supply reel onto several working spools, and optionally of an outer cover made of a plastic material. An intermediate layer of plastic yarn is disposed between every two helically wound pressure-resisting layers. After being unwound, the wires necessary for the helically wound pressure-resisting layers are precoiled over a hardened edge in the rewinding device and then wound onto the working spool in the stretched state. In accordance with the preferred embodiment, precoiling is done, not in a stranding machine, during hose production, but one stage earlier, in the rewinding device, where the individual wires are rewound from a supply reel onto so-called working spools.

Abstract: There is disclosed an apparatus for manufacturing a synthetic resin hose having a tubular reinforcing member embedded therein, which comprises a hollow cylindrical member having diameter adjusting discs provided with yarn guide holes for guiding a plurality of bonding-agent applied warps to the outer peripheral surface of the hollow cylindrical member, and an adjusting disc for guiding braiding yarns to the outer peripheral surface of a tubular member formed by said plurality of warps; a braiding machine surrounding said hollow cylindrical member and weaving the braiding yarns into a braided member; a first heating unit surrounding said hollow cylindrical member and bonding the warp tabular member to the braided member at the contacts therebetween, thereby heat-setting a tubular reinforcing member consisting of the warp tubular member and the braided member; a resin applying unit having manifolds and die for coating synthetic resin to the inner and outer peripheral surfaces of said tubular reinforcing member;

Abstract: A hose resistant to deformation is described which includes the usual polymeric tube and outer cover, and at least one annular reinforcement layer of fiber bundles sandwiched between the tube and cover. A polymeric aqueous-insoluble continuous film impregnates the fiber bundles and binds the reinforcement to at least one of the cover and tube, the continuous polymeric film serving to unexpectedly stiffen the hose appreciably. A method for producing the hose is described wherein the adhesive film is formed by applying a latex dispersion to the hose tube and/or reinforcement.

Abstract: A laminated tubular structure is obtained by a process in which a fabric sleeve is applied about a tube of thermoplastic polymer, following which plugs are inserted into the opposing ends of the liner. A liquid, such as water, is then introduced to the liner, and the liner is rotated about a horizontal axis while heat is applied to the exterior surface of the liner, causing the surface to become molten. The heat also causes vaporization of some of the liquid in the liner and the resulting vapor pressure causes the molten surface of the liner to expand radially into the interstices of the fabric sleeve. The inner surface of the liner remains solid and form-maintaining by reason of the liquid within the liner and heat absorbed on vaporization of liquid. Upon cooling there is obtained a good mechanical bond between the liner and sleeve.

Abstract: A method of hose production and product wherein a thermoplastic core tube having an outer surface has applied thereto a metallic reinforcement equipped with interstices, the assembly thus achieved being heated in selected portions adjacent the outer surface of the tube to soften the tube for migration into the interstices and thereafter cooling the migrant portions to form a uniform mechanical interlock between the core tube and reinforcement and, further, a uniform mechanical interlock between the core tube, reinforcement and cover.

Abstract: A braided-wire sheathing for high pressure hose or the like composed of interwoven bundles of high tensile strength wire. Within each bundle, the longer wires are twisted helically about the shorter wires such that all of the wires are under substantially equal tension. The interwoven bundles are grouped in pairs in a two-over, two-under pattern, the two bundles in each pair being twisted in opposing rotational directions.

Abstract: An improved process for manufacturing a synthetic resin hose having a reinforcing member embedded therein, comprising applying a bonding agent to a plurality of warp materials in a bonding agent tub; guiding the warps through yarn guide holes provided in a diameter ajusting disk to the outer peripheral surface of a hollow cylindrical member; forming a warped tubular member arranged side by side with a space each other and parallel to the axis of the tubular member by drawing it in the longitudinal axial direction of a hose being formed; weaving a plurality of braiding yarns into a braid member consecutively in overlying relation around on the outer peripheral surface of said warp tubular member, thereby forming a tubular reinforcing member; bonding warps to braided yarns at the contacts therebetween by passing a first heating unit, thereby heat-setting the tubular reinforcing member; solidifying the tubular reinforcing by passing a first cooling unit; coating synthetic resin onto the inner and outer periphera

Abstract: The invention relates to a process for the continuous extrusion forming of a thermoplastic double-walled, foam-core conduit by the sequential steps of extrusion forming an inner plastic tube, evenly coating said inner tube with foam-core layer and extrusion forming and bonding an outer tube in contact with said foam-core layer, said outer tube being generally evenly spaced apart from said inner tube by said foam-core layer providing a plastic double-walled, foam-core conduit.

Abstract: A reinforced tubular article such as a hose is manufactured by at least partially vulcanizing a rubber composition to form an inner tube and forming on the outer surface of said inner tube an assembly of reinforcing members which are united with the inner tube by a solidifiable liquid polymer material which when solidified bonds to both the reinforcing members and the outer surface of the tube.

Abstract: A composite reinforced hose for conveying paint under pressure is provided with a core tube simultaneously coextruded from two or more thermoplastic synthetic polymers which are in intimate contact with each other. The inner layer of the core tube is nylon or other chemical resistant polymer which is substantially non-conductive and the outer layer is electrically conductive. The conductive polymer layer serves as a ground for static electricity.

Abstract: A high pressure hose construction and method of and apparatus for making the same is disclosed wherein the hose construction has a smooth walled inner liner of resilient polymeric material, and an adhesive layer, which may also be of polymeric material bonded to the liner. A braided cover is disposed over the entire layer and embedded therein. This braided cover is comprised of a plurality of elongated intermeshing strands of non-metallic fibers, such as yarn, and metallic fibers. Preferably, every three strands are of flexible, non-metallic fibers, such as nylon fibers, and every fourth strand is of metallic fiber, such as piano wire or spring steel. One set of strands crosses over and under another set to produce an intermeshing or weaving effect. These strands may also extend in a direction at an angle, such as 45.degree. or 53.degree.

Abstract: An apparatus and process for producing a unique, continuous and endless, bias cut fabric employing ceramic and synthetic fibers is disclosed. The apparatus comprises a take up roll system positioned at the output of a tubular weaving operation.The roll system takes up the tube evenly and ensures a uniform movement of the tube through the system to maintain a uniform weave oriented at 90.degree. to the fabric length.This permits the tube, as it leaves the system, to be cut diagonally and to be unwound as a lay flat fabric having a uniform weave pattern oriented at a bias to the fabric length.

Abstract: A polymeric hose and method of making same are provided wherein such hose comprises an inner base tube, a reinforcing braid made of aramid yarn disposed concentrically around the base tube with the aramid yarn having great affinity for water, a cover tube disposed concentrically around the reinforcing braid, and a moisture-impervious tubular film disposed between the braid and cover tube with the film isolating the aramid yarn and resulting in a tubular zone between the braid and cover tube free of water moisture created bubbles.

Abstract: A thermoplastic hose is disclosed in which a reinforcement layer is made fom a combination of yarns and monofilaments to provide stereo interstices where mechanical bonds between the reinforcement and its adjacent element of the hose can be established.

Abstract: Sacks are made from a web comprising a tube of stretched plastics tape fabric woven around a thermoplastic tubular film. The web is continuously fed to a storage device from which two-ply sack lengths are intermittently withdrawn and severed and provided with a stitched base seam. Each severing cut is made to extend through transverse strips of hot-melt adhesive which were applied to both sides of the fabric tube and cooled. After severing and prior to stitching through both plies, the inner ply is provided with a separate base seam by means of welding jaws.

Abstract: The invention relates to building.The invention relates to a building device characterised in that it comprises a layer of at least one knitted fabric elastically deformable in all directions on an at least temporarily supporting skeleton, and a binder capable of setting on the knitted fabric.

Abstract: Hydraulic circuits having flexible hydraulic hoses forming part of the circuits are currently being operated at pressures in excess of 3,000 psi, and such circuits are often limited in their operating pressure by the burst strength of the hydraulic hose. By constructing a hollow core structure that forms the conduit and which serves as the foundation upon which the reinforcing is applied, with a two-layer tape composed of a layer of fabric and a layer of elastomer, which tape is then wound on a mandrel in a helically overlapping relationship with the fabric on the outside, an improved hose can be obtained after the reinforcing is applied. An increase in burst strength can be obtained in such a hose where wire cable is employed as the reinforcing in place of monofilament wire reinforcing, when the cable is formed (twisted) as it is applied, to achieve a more uniform tension on each of the strands forming the cable encircling the core structure.

Abstract: A high pressure hose construction and method of and apparatus for making the same is disclosed wherein the hose construction has a smooth walled inner liner of resilient polymeric material, and an adhesive layer, which may also be of polymeric material bonded to the liner. A braided cover is disposed over the entire layer and embedded therein. This braided cover is comprised of a plurality of elongated intermeshing strands of non-metallic fibers, such as yarn, and metallic fibers. Preferably, every three strands are of flexible, non-metallic fibers, such as nylon fibers, and every fourth strand is of metallic fiber, such as piano wire or spring steel. One set of strands crosses over and under another set to produce an intermeshing or weaving effect. These strands may also extend in a direction at an angle, such as 45.degree. or 53.degree.

Abstract: Elastomeric hose having relatively low thermal conductivity is provided comprising an outer tubular cover vulcanized to an inner tube, the outer cover being radially expanded and having a cellular or porous network formed therein. A braided or knitted reinforcing layer may be provided between the radially expanded cellular cover and the inner tube with the former being bonded or vulcanized to the latter through the interstices of the reinforcing layer. The elastomeric hose may be formed by a process wherein a first forming composition, including a thermosetable elastomer, is extruded to form an uncured inner tube which is then simultaneously introduced into a cross-head extruder with a second, separately prepared, forming composition including a thermosetable elastomer and a blowing agent.

Abstract: A composite drive shaft having a hollow tubular, multi-layered fiber reinforced plastic shaft portion (11) with a metallic sleeve (13) inserted in and bonded thereto at least at one end, said sleeve (13) having universal joint connector means (12).

Abstract: A method for producing a high strength flexible composite hose, and a hose produced by the method. The method includes forming a hollow inner core of uncured thermosetting elastomeric material. One or more layers of reinforcement material are applied to the outer peripheral surface of the uncured core. The uncured core and the reinforcement material are then encapsulated with a thermoplastic elastomeric cover while maintaining the temperature of the core below its vulcanization temperature. The temperature of the core and reinforcement material and cover is then increased to and maintained at a temperature which is at least as great as the vulcanization temperature of the core but less than the melting temperature of the cover for a time sufficient to vulcanize the core.

Abstract: A fibrous reinforced flexible hose for conveying fluids such as paint under pressure is provided with a composite core tube preferably simultaneously co-extruded from two or more synthetic polymers which are in intimate contact with each other. The inner layer of the composite core tube is nylon or other chemical resistant polymer which may or may not be cross-linked and the outer layer is a cross-linked electrically semi-conductive synthetic polymer layer which serves as a ground for static electricity. In the process of making the hose, the semi-conductive layer is preferably cross-linked by irradiation as a means of improving its higher temperature performance capabilities and to minimize changes in the electrical resistance of the semi-conductive layer that might arise from dynamic use of the hose.

Abstract: There is disclosed an apparatus for manufacturing a synthetic resin hose having a tubular reinforcing member embedded therein, which comprises a hollow cylindrical member having diameter adjusting discs provided with yarn guide holes for guiding a plurality of bonding-agent applied warps to the outer peripheral surface of the hollow cylindrical member, and an adjusting disc for guiding braiding yarns to the outer peripheral surface of a tubular member formed by said plurality of warps; a braiding machine surrounding said hollow cylindrical member and weaving the braiding yarns into a braided member; a first heating unit surrounding said hollow cylindrical member and bonding the warp tubular member to the braided member at the contacts therebetween, thereby heat-setting a tubular reinforcing member consisting of the warp tubular member and the braided member; a resin applying unit having manifolds and die for coating synthetic resin to the inner and outer peripheral surfaces of said tubular reinforcing member;

Abstract: Hydraulic circuits having flexible hydraulic hoses forming part of the circuits are currently being operated at pressures in excess of 3,000 psi, and such circuits are often limited in their operating pressure by the burst strength of the hydraulic hose. By constructing a hollow core structure that forms the conduit and which serves as the foundation upon which the reinforcing is applied, with a two-layer tape composed of a layer of fabric and a layer of elastomer, which tape is then wound on a mandrel in a helically overlapping relationship with the fabric on the outside, an improved hose can be obtained after the reinforcing is applied. An increase in burst strength can be obtained in such a hose where wire cable is employed as the reinforcing in place of monofilament wire reinforcing, when the cable is formed (twisted) as it is applied, to achieve a more uniform tension on each of the strands forming the cable encircling the core structure.

Abstract: A composite reinforced vulcanized elastomeric hose is disclosed including a tube, an outer cover, an interlayer interposed between the tube and cover, and a reinforcement embedded in the hose wall. The outer cover and inner tube are composed of dissimilar polymers not readily bondable to one another, one of which is an EPDM type, and the interlayer is composed of halogenated butyl which securely bonds the dissimilar polymers together and provides a low permeability internal fluid barrier for the hose article with protection to the embedded reinforcement.

Abstract: This invention constitutes an improvement upon the existing practice of manufacturing reinforced automotive heater hose and the like in a continuous operation which comprises continuously extruding an elastomeric tube, continuously applying to the outer surface of the tube an appropriate reinforcing layer of textile yarns or the like, continuously extruding over the reinforcing layer an elastomeric covering layer, and continuously curing the elastomeric components in an elongated chamber containing heat exchange elements the improvement residing in the provision of a method and means for elongating within certain limits the uncured or partially cured hose during the curing process whereby reduction of pressure and temperature within the extruding units and other advantages in production of reinforced automotive heater hose and the like may be realized.

Abstract: A conduit such as a metal or flexible material fuel or oil tube is provided with a barrier to metallic fires through the use of the combination of carbon or graphite impregnated with a polymer resin to provide insulative as well as ablative characteristics.

Abstract: A flexible hose construction and method of making same are provided wherein such hose construction comprises a flexible nylon-11 base tube, a braided reinforcing layer disposed around the base tube, and a layer of adhesive means between the base tube and reinforcing layer consisting of a mixture of a urethane prepolymer and a cross-linking material (4,4'methylene-bis-chloroaniline) defining the sole means bonding the braided reinforcing layer to the base tube.

Abstract: An irradiated polyethylene tube is supported on a mandrel with adhesive material applied against its outside surface whereupon a first tubular layer is braided against the adhesive means followed by a tubular layer of neoprene rubber followed by braiding a second tubular layer against the neoprene rubber to define an assembly which is subjected to a controlled temperature environment to simultaneously vulcanize the rubber and bond the tube and tubular layers together defining the hose construction as a unitary structure.

Abstract: Rubber hose with textile thread reinforcing is produced by extruding an inner tube of rubber material, cooling the extruded tube, applying a covering of textile thread over the inner tube and then extruding an outer layer of rubber material over the textile layer. Just before the outer layer is extruded on the inner tube it is heated by subjecting it to an ultrahigh frequency field. The outer layer is extruded on under a vacuum so that the inner tube which has been softened by the UHF heating is supported by the resulting pressure differential. The resulting hose is then vulcanized. By reason of the preheating of the inner tube, the inner and outer rubber layers are at approximately the same temperature and hence vulcanized equally. The application of a vacuum during the second extrusion has the further advantage of avoiding air inclusions between the inner and outer rubber layers.

Abstract: A partially cured flexible vulcanizable core useful in the manufacture of hose, for instance, is produced by passing the vulcanizable core through a microwave zone while simultaneously contacting only the outer surface of the core with a cool stream of fluid, so that the core becomes substantially cured with the exception of a layer at the outer surface of the core, which remains substantially uncured.

Abstract: A method and apparatus are disclosed for producing a composite pipe for handling destructive materials under pressure and vacuum conditions. The pipe includes a tubular liner formed of thermoplastic material capable of withstanding the destructive material. A strip of glass fiber fabric is helically wrapped around the outer surface of the liner. Heat is applied externally to the wrapped liner at a sufficient rate to simultaneously melt the exterior surface of the liner and thermally expand the liner radially outwardly into the openings in the fabric. Upon cooling, a permanent mechanical bond is achieved between the liner and the fabric. A layer of fiber glass and resin is then applied to the outer surface of the wrapped liner for structional rigidity and strength.

Abstract: A vulcanized reinforced elastomeric hose and a method for its production wherein a layer of uncured rubber supported on a mandrel is surrounded by reinforcement filaments and thereafter vulcanized. In the same method of the invention recesses are provided in the surface of the uncured rubber beneath the reinforcement filaments to accommodate expansion of the mandrel and/or expansion of the uncured rubber and/or shrinkage of the filaments and thereby prevent rubber from being exuded above the reinforcement filaments on curing.