# US 9,435,468 B2 · Construction of pipes > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,435,468 B2 - Document ID: US9435468B2 - Status: Granted - Kind: B2 - Application number: 14/353,908 - Filed: 2011-10-31 - Published: 2014-09-18 - Granted: 2016-09-06 - Earliest claimed: 2010-10-29 - Assignees: Long Pipes (Pty) Ltd. - Applicants: Neil Deryck Bray Graham - Inventors: Neil Deryck Bray Graham - Web page: https://patentgrep.com/patent/US9435468B2 ## CPC - F16L 9/14: Compound tubes, i.e. made of materials not wholly covered by any one of the preceding groups (F16L9/16 - F16L9/22 take precedence) - B29C 53/48: for articles of indefinite length, i.e. bending a strip progressively - B29C 63/343: {the tubular sheathing having a deformed non-circular cross-section prior to introduction} - B29C 65/4815: {Hot melt adhesives, e.g. thermoplastic adhesives} - B29C 65/5021: {being multi-layered} - B29C 65/5028: {being textile in woven or non-woven form} - B29C 65/52: {characterised by the way of} applying the adhesive {(B29C65/50 takes precedence; apparatus for applying liquids in general B05C; processes for applying liquids in general B05D)} - B29C 70/50: for producing articles of indefinite length, e.g. prepregs, sheet moulding compounds [SMC] or cross moulding compounds [XMC] - B29D 23/001: {Pipes; Pipe joints (pleated hoses B29D23/18)} - B29D 23/18: Pleated {or corrugated} hoses - B32B 1/08: Tubular products - B32B 5/02: characterised by structural features of a {fibrous or filamentary} layer {(layer formed of metallic wires B32B15/02; layer formed of natural mineral fibres B32B19/02; layer formed of wood fibres B32B21/02)} - B32B 5/12: characterised by the relative arrangement of fibres or filaments of {different layers, e.g. the fibres or filaments being parallel or perpendicular to each other} - B32B 5/26: another layer {next to it} also being fibrous or filamentary {(relative arrangement of fibres or filaments of different layers B32B5/12)} - B32B 13/14: next to a fibrous or filamentary layer - B32B 27/32: comprising polyolefins {(comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30)} - B32B 27/40: comprising polyurethanes - F16L 11/04: made of rubber or flexible plastics - F16L 13/147: {by radially expanding the inner part (F16L13/168 takes precedence)} - F16L 55/1654: {and being inflated} - F16L 55/1656: {materials for flexible liners} - B29C 53/066: {and joining the sides of the folding line, e.g. "Abkantschweissen"} - B29C 53/382: {using laminated sheets} - B29C 63/28: applied by "rubber" bag or diaphragm - B29C 63/341: {pressed against the wall by mechanical means} - B29C 65/5042: {covering both elements to be joined} - B29C 66/1122: {Single lap to lap joints, i.e. overlap joints (B29C66/45, B29C66/472, B29C66/52272 take precedence)} - B29C 66/1142: {Single butt to butt joints} - B29C 66/4322: {by joining a single sheet to itself (B29C66/4332 takes precedence)} - B29C 66/71: {characterised by the composition of the plastics material of the parts to be joined (welding bar compositions B29C65/125)} - B29C 66/73161: {Roughness or rugosity} - B29L 2023/22: {Tubes or pipes, i.e. rigid (bent tubes not for use as pipe couplings B29L2023/004)} - B32B 2260/023: Two or more layers - B32B 2260/046: Synthetic resin - B32B 2262/101: Glass fibres - F16L: PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL - B29C: SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING (making preforms B29B11/00; making laminated products by combining previously unconnected layers which become one product whose layers will remain together B32B37/00 - B32B41/00) - B29D: PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE (making granules B29B9/00; making preforms B29B11/00) - B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM - B29L: INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES ## Abstract An elongate hollow structure and method of constructing the hollow structure is described, the hollow structure including a radially inner portion and a radially outer portion merging together to form a tubular wall structure. The method includes providing the radially inner portion, assembling the radially outer portion about the radially inner portion, and radially expanding the inner portion. The outer portion comprises an outer layer of fiber reinforced composite construction surrounded by a flexible outer casing. A space is provided between the radially inner portion and flexible outer casing. The outer layer includes reinforcement and a binder. The flexible outer casing resists radial expansion of the reinforcement, subjecting it to radial compression. The radially expanding inner portion cooperates with the flexible outer casing to cause the volume of the space to progressively decrease, causing the binder to spread through the space between the radially inner portion and flexible outer casing. ## Claims ### Claim 1 A method of constructing an elongate hollow structure, the elongate hollow structure having a radially inner portion and a radially outer portion, with the two portions merging together to provide an integrated tubular wall structure, the method comprising: providing the radially inner portion, assembling the radially outer portion about the radially inner portion, and radially expanding the inner portion, wherein the outer portion comprises an outer layer of fibre reinforced composite construction surrounded by a flexible outer casing, and wherein there is a space between the radially inner portion and the flexible outer casing, the outer layer of fibre reinforced composite construction comprises reinforcement and a binder, the flexible outer casing serves to resist radial expansion of the reinforcement, thereby causing it to be subjected to radial compression, the radially expanding inner portion operates in conjunction with the flexible outer casing to cause the volume of the space between the radially inner portion and the flexible outer casing to progressively decrease, thereby causing the binder within the reinforcement to spread through the space between the radially expanding inner portion and the flexible outer casing, and the flexible outer casing has less resilience than the radially expanding inner portion so as to yieldingly resist radial expansion of the inner portion. ### Claim 2 (depends on 1) The method of claim 1, wherein the reinforcement is impregnated with the binder and comprises one or more layers of reinforcing fabric. ### Claim 3 (depends on 2) The method of claim 2, wherein each of the one or more layers of reinforcing fabric is configured as a tubular layer disposed about the radially expanding inner portion. ### Claim 4 (depends on 3) The method of claim 3, wherein there is a plurality of tubular layers disposed one about another and about the radially expanding inner portion. ### Claim 5 (depends on 2) The method of claim 2, wherein the radially expanding inner portion includes an inner liner with a fibrous layer bonded onto one face thereof, wherein the binder impregnating the reinforcing fabric also impregnates the fibrous layer to integrate the outer portion with the inner portion. ### Claim 6 (depends on 3) The method of claim 3, wherein the binder is confined in the space between the radially expanding inner portion and the flexible outer casing, whereby the radially expanding inner portion operates in conjunction with the flexible outer casing to cause the volume of the space to progressively decrease thereby to cause expulsion of air from within the space. ### Claim 7 (depends on 6) The method of claim 6, wherein the outer casing and the various reinforcing fabric tubular layers are configured to facilitate expulsion of the air. ### Claim 8 (depends on 3) The method of claim 3, wherein the flexible outer casing has some resilience in order to yieldingly resist radial expansion of the reinforcing fabric tubular layers. ### Claim 9 (depends on 1) The method of claim 1, wherein the flexible outer casing has elasticity for the purpose of enhancing control of the rate at which the binder spreads through the space between the radially expanding inner portion and the flexible outer casing. ### Claim 10 (depends on 1) The method of claim 1, wherein the elongate hollow structure is constructed on a continuous basis and progressively installed in position prior to curing of the tubular wall structure, whereby the tubular wall structure cures once in the installed position of the elongate hollow structure. ### Claim 11 A method of constructing a pipe on a continuous basis, comprising: forming a flexible tubular wall structure comprising a radially inner tube, a fibre-reinforced plastic composite, and a radially outer, inflating the inner tube to provide form and shape thereto, and curing the flexible wall structure to provide the pipe, wherein there is a space between the inner tube and the outer, the fibre reinforced composite construction comprises reinforcement and a binder and is located between the inner outer, the outer serves to resist radial expansion of the inner tube causing it to be subjected to radial compression, the radially expanding inner tube operates in conjunction with the outer to cause the volume of the space between the inner tube and the outer to progressively decrease, thereby causing the binder to spread through the space between the inner tube and the outer tube, and the outer tube has less resilience than the inner tube so as to yieldingly resist radial expansion of the inner tube. ### Claim 12 (depends on 11) The method of claim 11, wherein the pipe is in a flexible condition, the method further comprising: laying the pipe at an installation site, and allowing the flexible pipe to transform into a rigid condition at the installation site. ### Claim 13 (depends on 12) The method of claim 12, wherein the pipe is assembled in a mobile installation plant which can move with respect to the installation site, laying the pipe in the flexible condition. ### Claim 14 (depends on 11) A mobile installation plant for constructing a pipe in accordance with the method of claim 11. ### Claim 15 (depends on 1) An assembly line for constructing an elongate hollow structure in accordance with the method of claim 1. ### Claim 16 (depends on 1) An elongate hollow structure constructed in accordance with the method of claim 1. ### Claim 17 An elongate hollow structure of composite construction, comprising: a radially inner portion, and a radially outer portion, wherein the two portions are merged together to provide an integrated tubular wall structure, and wherein the radially outer portion is configured as an outer tube of fibre reinforced composite construction including reinforcement, the radially outer portion is configured, at least during construction, as a flexible outer casing that serves to resist radial expansion of the reinforcement, thereby causing it to be subjected to radial compression, the inner portion and outer tube are spaced apart, the fibre reinforced composite construction comprises the reinforcement and a binder and is located between the inner portion and the outer, the outer serves to resist expansion of the inner portion causing the inner portion to be subjected to compression, the binder is spread between the inner portion and the outer due to the expansion of the inner portion, operating in conjunction with the outer to cause the volume of the space between the inner portion and the outer tube to progressively decrease during the formation of the elongate hollow structure, thereby causing the binder to spread through the space between the inner portion and the outer tube, and the flexible outer casing has less resilience than the radially expanding inner portion so as to yieldingly resist radial expansion of the inner portion. ### Claim 18 (depends on 17) The elongate hollow structure of claim 17, wherein the reinforcement is impregnated with the binder and comprises one or more layers of reinforcing fabric, each of the one or more layers of reinforcing fabric configured as a tubular layer disposed about the inner portion. ### Claim 19 (depends on 18) The elongate hollow structure of claim 18, wherein the reinforcing fabric comprises reinforcing fabric incorporating reinforcement fibres featuring quadraxial fibre orientations. ### Claim 20 (depends on 17) The elongate hollow structure of claim 17, wherein the inner portion comprises an inner liner with a fibrous layer bonded onto one face thereof. ### Claim 21 (depends on 20) The elongate hollow structure of claim 20, wherein a face of the inner liner other than the one face defines the interior surface of the tubular wall structure. ### Claim 22 (depends on 18) The elongate hollow structure of claim 18, wherein the inner portion further includes an inner liner with a fibrous layer bonded onto one face thereof, and resinous binder also impregnates the fibrous layer to integrate the outer portion with the inner portion. ### Claim 23 (depends on 1) The method of claim 1, wherein the fibre reinforced composite serves to increase the load bearing properties of the elongate hollow structure. ### Claim 24 (depends on 6) The method of claim 6, wherein the outer casing includes venting means to facilitate the expulsion of air. ### Claim 25 (depends on 1) The method of claim 1, wherein the inner portion is expanded by injecting an inflation fluid into the inner portion. ### Claim 26 (depends on 25) The method of claim 25, wherein the inner portion is expanded with inflation fluid that is introduced from an end of the elongate hollow structure. ### Claim 27 (depends on 25) The method of claim 25, wherein the elongate hollow structure is compressed at a location distal to an end from which the inflation fluid is introduced so that inflation fluid cannot pass through the location distal to the end. ### Claim 28 (depends on 27) The method of claim 27, wherein the elongate hollow structure passes through a compression device, and the compression device compresses the elongate hollow structure within it so that the inflation fluid cannot pass through the location distal to the end. ### Claim 29 (depends on 27) The method of claim 27, wherein the elongate hollow structure passes through a compression device, and the compression device acts to control the rate at which the elongate hollow structure is constructed. ### Claim 30 (depends on 27) The method of claim 27, wherein the elongate hollow structure passes through a compression device, and the compression device applies traction to the elongate hollow structure to facilitate continued construction of the elongate hollow structure. ### Claim 31 (depends on 1) The method of claim 1, wherein a bend is incorporated into the elongate hollow structure during construction so that the elongate hollow structure, when cured, includes at least one integral bend. ### Claim 32 (depends on 1) The method of claim 1, wherein an end of the elongate hollow structure is configured so as to securely receive an anchoring portion, the anchoring portion enabling the elongate hollow structure to couple to a second structure. ### Claim 33 (depends on 1) The method of claim 1, wherein the binder is caused to spread throughout the space so as to completely fill the space between the radially inner portion and the flexible outer casing, as the volume of the space between the radially inner portion and the flexible outer casing is progressively decreased.