EP0797500A1 - Remise en forme d'elements thermoplastiques - Google Patents

Remise en forme d'elements thermoplastiques

Info

Publication number
EP0797500A1
EP0797500A1 EP95941181A EP95941181A EP0797500A1 EP 0797500 A1 EP0797500 A1 EP 0797500A1 EP 95941181 A EP95941181 A EP 95941181A EP 95941181 A EP95941181 A EP 95941181A EP 0797500 A1 EP0797500 A1 EP 0797500A1
Authority
EP
European Patent Office
Prior art keywords
heating
thermoplastics
forming
lining
pipe
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP95941181A
Other languages
German (de)
English (en)
Inventor
John Wood
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Publication of EP0797500A1 publication Critical patent/EP0797500A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L55/00—Devices or appurtenances for use in, or in connection with, pipes or pipe systems
    • F16L55/16—Devices for covering leaks in pipes or hoses, e.g. hose-menders
    • F16L55/162—Devices for covering leaks in pipes or hoses, e.g. hose-menders from inside the pipe
    • F16L55/165—Devices for covering leaks in pipes or hoses, e.g. hose-menders from inside the pipe a pipe or flexible liner being inserted in the damaged section
    • F16L55/1652—Devices for covering leaks in pipes or hoses, e.g. hose-menders from inside the pipe a pipe or flexible liner being inserted in the damaged section the flexible liner being pulled into the damaged section
    • F16L55/1654—Devices for covering leaks in pipes or hoses, e.g. hose-menders from inside the pipe a pipe or flexible liner being inserted in the damaged section the flexible liner being pulled into the damaged section and being inflated
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
    • B29B13/00—Conditioning or physical treatment of the material to be shaped
    • B29B13/02—Conditioning or physical treatment of the material to be shaped by heating
    • B29B13/023—Half-products, e.g. films, plates
    • B29B13/024—Hollow bodies, e.g. tubes or profiles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE 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
    • B29C35/00—Heating, cooling or curing, e.g. crosslinking or vulcanising; Apparatus therefor
    • B29C35/02—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould
    • B29C35/08—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation
    • B29C35/10—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation for articles of indefinite length
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE 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
    • B29C55/00—Shaping by stretching, e.g. drawing through a die; Apparatus therefor
    • B29C55/22—Shaping by stretching, e.g. drawing through a die; Apparatus therefor of tubes
    • B29C55/24—Shaping by stretching, e.g. drawing through a die; Apparatus therefor of tubes radial
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE 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
    • B29C63/00—Lining or sheathing, i.e. applying preformed layers or sheathings of plastics; Apparatus therefor
    • B29C63/0065—Heat treatment
    • B29C63/0069—Heat treatment of tubular articles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE 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
    • B29C63/00—Lining or sheathing, i.e. applying preformed layers or sheathings of plastics; Apparatus therefor
    • B29C63/26—Lining or sheathing of internal surfaces
    • B29C63/34—Lining or sheathing of internal surfaces using tubular layers or sheathings
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE 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
    • B29C66/00—General aspects of processes or apparatus for joining preformed parts
    • B29C66/50—General aspects of joining tubular articles; General aspects of joining long products, i.e. bars or profiled elements; General aspects of joining single elements to tubular articles, hollow articles or bars; General aspects of joining several hollow-preforms to form hollow or tubular articles
    • B29C66/61—Joining from or joining on the inside
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE 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
    • B29C35/00—Heating, cooling or curing, e.g. crosslinking or vulcanising; Apparatus therefor
    • B29C35/02—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould
    • B29C35/08—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation
    • B29C35/0805—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation using electromagnetic radiation
    • B29C2035/0822—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation using electromagnetic radiation using IR radiation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE 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
    • B29C65/00—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor
    • B29C65/02—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure
    • B29C65/14—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using wave energy, i.e. electromagnetic radiation, or particle radiation
    • B29C65/1403—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using wave energy, i.e. electromagnetic radiation, or particle radiation characterised by the type of electromagnetic or particle radiation
    • B29C65/1412—Infrared [IR] radiation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE 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
    • B29C66/00—General aspects of processes or apparatus for joining preformed parts
    • B29C66/01—General aspects dealing with the joint area or with the area to be joined
    • B29C66/05—Particular design of joint configurations
    • B29C66/10—Particular design of joint configurations particular design of the joint cross-sections
    • B29C66/11—Joint cross-sections comprising a single joint-segment, i.e. one of the parts to be joined comprising a single joint-segment in the joint cross-section
    • B29C66/112—Single lapped joints
    • B29C66/1122—Single lap to lap joints, i.e. overlap joints
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE 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
    • B29C66/00—General aspects of processes or apparatus for joining preformed parts
    • B29C66/50—General aspects of joining tubular articles; General aspects of joining long products, i.e. bars or profiled elements; General aspects of joining single elements to tubular articles, hollow articles or bars; General aspects of joining several hollow-preforms to form hollow or tubular articles
    • B29C66/51—Joining tubular articles, profiled elements or bars; Joining single elements to tubular articles, hollow articles or bars; Joining several hollow-preforms to form hollow or tubular articles
    • B29C66/53—Joining single elements to tubular articles, hollow articles or bars
    • B29C66/532—Joining single elements to the wall of tubular articles, hollow articles or bars
    • B29C66/5326—Joining single elements to the wall of tubular articles, hollow articles or bars said single elements being substantially flat
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE 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
    • B29C66/00—General aspects of processes or apparatus for joining preformed parts
    • B29C66/70—General aspects of processes or apparatus for joining preformed parts characterised by the composition, physical properties or the structure of the material of the parts to be joined; Joining with non-plastics material
    • B29C66/71—General aspects of processes or apparatus for joining preformed parts characterised by the composition, physical properties or the structure of the material of the parts to be joined; Joining with non-plastics material characterised by the composition of the plastics material of the parts to be joined
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE 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
    • B29C66/00—General aspects of processes or apparatus for joining preformed parts
    • B29C66/70—General aspects of processes or apparatus for joining preformed parts characterised by the composition, physical properties or the structure of the material of the parts to be joined; Joining with non-plastics material
    • B29C66/73—General aspects of processes or apparatus for joining preformed parts characterised by the composition, physical properties or the structure of the material of the parts to be joined; Joining with non-plastics material characterised by the intensive physical properties of the material of the parts to be joined, by the optical properties of the material of the parts to be joined, by the extensive physical properties of the parts to be joined, by the state of the material of the parts to be joined or by the material of the parts to be joined being a thermoplastic or a thermoset
    • B29C66/739—General aspects of processes or apparatus for joining preformed parts characterised by the composition, physical properties or the structure of the material of the parts to be joined; Joining with non-plastics material characterised by the intensive physical properties of the material of the parts to be joined, by the optical properties of the material of the parts to be joined, by the extensive physical properties of the parts to be joined, by the state of the material of the parts to be joined or by the material of the parts to be joined being a thermoplastic or a thermoset characterised by the material of the parts to be joined being a thermoplastic or a thermoset
    • B29C66/7392—General aspects of processes or apparatus for joining preformed parts characterised by the composition, physical properties or the structure of the material of the parts to be joined; Joining with non-plastics material characterised by the intensive physical properties of the material of the parts to be joined, by the optical properties of the material of the parts to be joined, by the extensive physical properties of the parts to be joined, by the state of the material of the parts to be joined or by the material of the parts to be joined being a thermoplastic or a thermoset characterised by the material of the parts to be joined being a thermoplastic or a thermoset characterised by the material of at least one of the parts being a thermoplastic
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE 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
    • B29C66/00—General aspects of processes or apparatus for joining preformed parts
    • B29C66/80—General aspects of machine operations or constructions and parts thereof
    • B29C66/81—General aspects of the pressing elements, i.e. the elements applying pressure on the parts to be joined in the area to be joined, e.g. the welding jaws or clamps
    • B29C66/814—General aspects of the pressing elements, i.e. the elements applying pressure on the parts to be joined in the area to be joined, e.g. the welding jaws or clamps characterised by the design of the pressing elements, e.g. of the welding jaws or clamps
    • B29C66/8145—General aspects of the pressing elements, i.e. the elements applying pressure on the parts to be joined in the area to be joined, e.g. the welding jaws or clamps characterised by the design of the pressing elements, e.g. of the welding jaws or clamps characterised by the constructional aspects of the pressing elements, e.g. of the welding jaws or clamps
    • B29C66/81455—General aspects of the pressing elements, i.e. the elements applying pressure on the parts to be joined in the area to be joined, e.g. the welding jaws or clamps characterised by the design of the pressing elements, e.g. of the welding jaws or clamps characterised by the constructional aspects of the pressing elements, e.g. of the welding jaws or clamps being a fluid inflatable bag or bladder, a diaphragm or a vacuum bag for applying isostatic pressure
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
    • B29K2023/00—Use of polyalkenes or derivatives thereof as moulding material
    • B29K2023/04—Polymers of ethylene
    • B29K2023/06—PE, i.e. polyethylene
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
    • B29K2995/00—Properties of moulding materials, reinforcements, fillers, preformed parts or moulds
    • B29K2995/0018—Properties of moulding materials, reinforcements, fillers, preformed parts or moulds having particular optical properties, e.g. fluorescent or phosphorescent
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
    • B29L2023/00—Tubular articles
    • B29L2023/22—Tubes or pipes, i.e. rigid

Definitions

  • the invention relates to re-forming thermoplastics members, including method and apparatus for re-sizing and re-shaping re-lining pipes for damaged or worn-out under ⁇ ground pipelines to avoid the need for excavation.
  • Such pipelines typically carry gas or water under head or pressure, or sewage ⁇ services, in urban areas.
  • Some existing pipe lines are over 100 years old and are in a sad state of disrepair due to various factors including damage due to ground movement, corrosion and crumbling.
  • Slip-lining is a simple alternative method for thermo ⁇ plastic re-lining.
  • An undersized, extruded thermoplastics pipe is dragged through the original pipeline and gaps left between the undersized pipe and the host pipeline are filled using a grout, at least to stop sewage etc intendedly entrant from lateral connections from flowing into/through such gaps.
  • grouting is often needed to stabilise the under-size slip-lining in position. Whether or not limited to positions of lateral connections, excavation is required at intervals for grouting, necessitating host pipeline run location being accurately determined from often old site- plans.
  • Swage-down systems can assist meeting annular gap problems of slip-lining, by taking a full-size re-lining thermoplastics pipe and squashing, or swaging, it undersize using hydraulic rams to fit it into the host pipeline.
  • High pressure air is used to re-expand the new pipe when it is in position, and thermoplastic memory from the pipe extrusion process as to full-size geometry assists system stability over time. Gaps are, however, not fully eliminated by this system since the match between the diameters of the old pipeline and the pre-swaged plastic pipe will only rarely be perfect.
  • some sections of re- lining pipe will be loose, and some parts the plastic pipe need to take on a distorted shape in order to fit.
  • Swage- down systems cannot produce a 'dimple' for use by robot hole-cutters, which means that each lateral connection position usually has to be excavated to re-connect it.
  • So-called U-liner systems are alternative to swage- down with two main differences.
  • the re-lining thermo ⁇ plastic pipe is extruded round then folded into a "U" shape in cross-section at the pipe manufacturing plant, so as to facilitate fitting inside a host pipeline.
  • the temperature at which the pipe is formed into the U shape is critical because of the way that temperature affects the pipe's thermoplastic memory.
  • steam is blown through the central channel of the folded re-lining pipe to soften it sufficiently for it to be inserted through a standard man- hole access to the host pipeline.
  • the re-lining pipe is inflated against the host pipeline using air pressure. It has been claimed that the steaming will induce a new thermoplastic memory for the pipe at this stage.
  • the close-fit tends to be short-lived, which is not surprising as simple steaming is limited to 100°C, thus below typical crystalline melt temperatures, e.g. 120°C for polyethylene, to be exceeded for erasing/ replacement of thermoplastic memory.
  • the pipe can seek to revert to the U shape because of imperfect temperature control during forming of the "U" shape off the extrusion line.
  • thermo-plastics member conveniently elongate, say tubular
  • a method of re-sizing or re-shaping a hollow thermo-plastics member comprising the steps of heating the thermoplastics material of the member to soften it, and applying fluid pressure, conveniently pressurised gas, to alter its size and/or shape, wherein the heating is by electromagnetic radiation to which the thermoplastics material both develops a degree of transparency without melting that at least reduces further heating up and softens enough to be re-sized and/or re-shaped as desired by said fluid pressure application.
  • re-forming is at or above a temperature at which thermoplastic memory as to original geometry becomes at least partially erased and usefully replaced by the re-formed geometry.
  • apparatus for re-sizing or re ⁇ shaping a hollow or thermoplastics member conveniently elongate, say tubular, comprising means for heating the thermoplastics material of the member to soften it, and means for applying fluid pressure, conveniently pressurised gas, to alter the size and/or shape of the hollow member after its thermo-plastic material is softened by said heating, wherein the means for heating serves to provide electromagnetic radiation to which said thermoplastics material is absorptive before developing a degree of transparency without melting that at least reduces further heating up and is then soft enough to be re-sized and/or re-shaped as desired by said fluid pressure, preferably at or above a temperature at which thermoplastic memory as to original geometry becomes at least partially erased and replaced.
  • this invention can be seen as seeking to modify known production processes blowing gas into soft, often near-molten, material to stretch and expand that material into a desired actual product.
  • Such processes are widely used, with or without external product-related form-imposing constraint or moulds, for producing such things as plastics film whether to be substantially form-sustaining or to be stretchable, inflatable elastomeric balloons, various hollow-ware often of necked bottle or flask type, etc.
  • production processes can be seen as derivative from, indeed include, age-old forming of hollow glassware. Initially, apparent absence of proposed application of such processes to re-forming, i.e. going from an initial already-made product form to a modified product form, with particular reference to thermoplastics products, seemed surprising.
  • melt temper ⁇ atures and other thermal properties of such materials particularly low heat conductivity and high specific heat (leading to very steep temperature gradients in normal wall thicknesses, typically 25mm and more, of re-lining pipe, that deleterious surface melting occurs before the whole is soft enough to expand satisfactorily, particularly when heating from one side only as is only practical from the interior of a re-lining pipe.
  • melt temper ⁇ atures and other thermal properties of such materials particularly low heat conductivity and high specific heat (leading to very steep temperature gradients in normal wall thicknesses, typically 25mm and more, of re-lining pipe, that deleterious surface melting occurs before the whole is soft enough to expand satisfactorily, particularly when heating from one side only as is only practical from the interior of a re-lining pipe.
  • Thermoplastics material adaptations can involve inclusions of other materials, for example conductive if contact heating is to be used, say by super-heated steam; or electrical reactance responsive if electrical induction heating is to be used; or other relevantly suitable suitably energy-absorptive, say for microwave heating.
  • inclusions could be of particulate or filamentary type, or be as sheets, such as of mesh or other expanded forms, say corrugated longitudinally if not otherwise expansible with desired re-forming of the thermoplastics material itself.
  • thermoplastics material may also assist in relation to internal heat retention and/or transparency/opaqueness adjustment, e.g. fine particles (typically 45 nanometres nominal) of carbon black in small quantities (typically 100 - 1000 ppm) .
  • temperature sensing and heating control means will ordinarily be required.
  • electro ⁇ magnetic radiation heating accompanied by transition to effective transparency, there will be a simple and automatic progressive softening from incident to opposite surface, with little or no further in-material heating at such transparency.
  • Any suitable compressed gas may be used, e.g. air or inert (such as carbon dioxide) for safety against explosion risks,- and, at least for re-lining a host pipeline, means can be provided for creating back pressure in the re-lining pipe downstream of the preferably movable heater to cause the softened pipe to re-size.
  • Suitable apparatus could include means for creating a pressure chamber sealed against the surface of the member, means for pressurizing the chamber and means for detecting a pressure drop in the chamber indicative, for example, of a rupture in the member.
  • the pressurizing means may apply pressure pulses to such chamber or against other suitable back-pressure.
  • Figure 1 is an overall longitudinal sectional view of one apparatus
  • FIG. 2 is a longitudinal sectional view of heating means,*
  • Figure 3 is an overall longitudinal sectional view of another apparatus;
  • Figure 4 is a schematic view of a device for detecting bursts in the wall of re-lining pipe,-
  • Figure 5 is a diagram showing heating re-lining pipe wall locally in restoring a lateral connection,- and
  • Figure 6 shows a further stage in restoring a lateral connection, after the heating stage of Figure 5.
  • heating machine 10 is pulled through undersized thermoplastics re-lining pipe 12 to soften it by its absorption of at least infra-red radiation 14.
  • Fluid pressure, specifically compressed gas 16 is used to expand the softened re-lining pipe 12 at ISA into contact with host pipeline 20 to exclude annular gaps, ideally give general closely intimate fit.
  • the fluid flow 16 is also shown at 16B cooling the expanded re-lining pipe 12.
  • the process can be continuous, with the heater 12 shown integrated with gas flow turbine 18.
  • Evacuated Halogen lamps or Ni-Chrome wire can serve as heating elements 22 and source of radiant infra-red heat, typically accompanied by visible light to which preferred thermo-plastics materials also become transparent.
  • Chromed or polished aluminium reflector(s) 24 usefully serve to direct the radiation from the heating elements 22, with forced cooling at 16C on its way to turbine drive nozzle 18N, to ensure that the heaters 22 and the reflectors 24 do not overheat within preferred transparent glass containing tube 23.
  • Electricity for driving preferred elongate, advantage ⁇ ously annular, arrays of heating lamps/elements 22 could be taken directly from electrical cables put into the pipe, but, as preferred on safety and logistical grounds, use is shown of a further integration into the heating machine 10 of a generator 30 shown having, inside and concentric with the array 22, windings 32 and rotating magnet assembly 34 in bearings 36, and also sharing cooling by incoming gas supply.
  • Input cold gas flow 16C to the turbo-generator 18/30 is shown coming through re-lining pipe end sealing gland 21 from an above-ground compressor 27 through an upstream manhole also accommodating haulage cable 29C from winch 29 through stabilising pulley provisions 29P and the gland 21.
  • the gas conveniently air, goes past elastomeric wiping seal 26 to the re-lining pipe 12 and is shown channelled at 27 to flow over the lamps/elements 22 and reflector(s) 24 to keep them cool in the glass tube 23. Cooling air-speeds of up to 100 meters/second can be used without incurring too much turbulent energy loss.
  • Combination heater/generator or heater/turbine or heater/generator/turbine machines for traversing pipes etc constitute another aspect of this invention by way of such combination(s) together, preferably with plural heating elements, conveniently in an annular preferably elongate array; and further preferably with trailing end turbine and/or inner reflector means and/or electric generator provision, conveniently either or both concentric with heating element array; and/or suitably transparent contain ⁇ ment of heating element(s) etc and/or defining a heating element(s) and reflector(s) cooling path for turbine gas supply; and/or (see below) control means for unwanted radiation components from the heater by suppression and/or filtering.
  • Preferred embodiments of such machine can be advantageously compact, particularly that can be winched through a 7-inch (ca. 175mm) re-lining pipe, including being no more than about 18" (ca. 450mm) long in order to negotiate normal bends.
  • thermal characteristics, including high latent heat, of most thermoplastics, perhaps particularly polyethylene lead to a joule-heat requirement for standard re-lining pipes of at least 25 kW of power to re-form a 100m length of pipe in one hour, which can be met by compact machines hereof capable of (non-limiting) projected practical minimum process speed to suit.
  • Turbo-generator requirements need be only four-pole, as frequency of operation is relatively unimportant for a generator so long as the load can be altered to suit the voltage that it outputs.
  • a 40kW, 40,000 RPM brushless motor could be driven in reverse by a turbine wheel to produce the required power.
  • thermoplastics typically polyethylene, re-lining pipe material soft, see Figure 4, the expansion pressure will stretch the material into any unsupported void, particularly of a lateral connection 60, at least to form a "dimple" 62, if not a burst 64 (dimple formation omitted) if inflation pressure is high enough and/or the material soft enough.
  • An unburst dimple 62 facilitates finding lateral connections 60 for later cutting, conveniently by a conventional cutter robot.
  • a blow-out hole 62 may self- heal to some extent, because, as soon as a hole forms, gas will rush out of it, cooling the thermoplastics material down and consolidating it. Loss of gas flow through small holes may not be significant, even int lateral connections, at the expansion pressure(s) envisaged. Compared to the very high flow through downstream back-pressure regulation valve 44, loss of air into laterals may not significantly affect the inflation pressure regulation.
  • a pre-liner could be used.
  • a thin sock of high strength, transparent, higher melt temperature plastic e.g. polypropylene
  • Detecting positions of burst-outs 64 might be simply by monitoring gas pressure changes at the back-pressure valve 44.
  • a simple pressurised gas machine 66 could be dragged through the re-formed re-lining pipe 12 (or 112) with end sealing provisions 68A,B and pressure loss detection signalled over line 69.
  • incidence of re-lining pipe blow-outs 64 is turned to advantage herein at lateral connections, see Figures 5 and 6.
  • a machine 70 (which could include position detection of
  • end sealing provisions 72A,B to define a chamber 74 which can be pressurized. Reduction in pressure in the chamber 74 again indicates the presence of a blow-hole as an increase in gas-flow above the normal leakage rate of the seal provisions 72A.B. Pulses of air could be used to avoid pressurising lateral connection 76 associated with the blow-hole 78.
  • Reinstating good lateral connection at 78 involves heating to softening the thermoplastics material locally, much as was done at installation.
  • An infra-red heat source 80 and directional reflector 84 on a rotatable carrier 86 serves to soften the area around the blow-hole 78/lateral connection 76, this time typically using an external electric source if allowed by the low power requirement.
  • the carrier 86 is rotated a half turn and a balloon 88 is inflated to push softened thermoplastics material into the lateral connection 76.
  • This machine 70 could be towed along behind the basic expansion machines 10 and 110 of Figures 1 to 3, and serve in desired back-pressuring.
  • thermoplastics of the pipe 12 should not be uneven and thus lead to local melting and cold spots.
  • heat absorption is virtually only in whatever is its instant penetration depth, and falling exponentially through it.
  • the penetration depth is low for opaque polyethylene due to intrinsic low thermal conductivity and high specific heat, which would cause surface melting, with remaining thickness staying cold.
  • For a fully transparent material there would, of course, be virtually no heat absorption at all.
  • So-called "natural” creamy-white polyethylene (due to crystallinity though free of normal pigments) discloses the property of going from opaque enough for absorption, including internal scattering effects, typically up to about 70% of incident infra-red radiation, to heat up to the desired temperature at which it goes transparent enough (or perhaps change of refractive index is involved, the exact mechanism not being fully understood at this stage, see below regarding optical transparency having been noted) to limit further heating below full melting; and to do so progressively through the thickness from incident to other surface, see idealised in sloping line 28.
  • thermoplastics materials are or may be particularly susceptible, including as to surface burning, e.g. fundamentals peaking at 0.9, 1.2 and 1.74 micrometre and odd (or coincident, e.g. 3.5 micrometre) harmonics for polyethylene,
  • suitable dielectric material can be installed on the glass tube 23, often a combination of materials and layers, say at 23A on its inner surface where reflection is involved in discrimination and unwanted radiation components eventually dissipate between the filter and the reflector 24.
  • the heating elements may be coated with frequency selective suppressive materials, such as various oxides on Ni-Chrome heating elements.
  • an appropriate sample of the thermoplastics material concerned could be used on a sacrificial basis as a filter.
  • infra-red is a preferred energy source
  • any frequency, or spectrum of frequencies which are absorbed by and heats the thermoplastic will work.
  • White-light halogen lamps are certainly feasible sources of power. They are understood to output about 40% of their energy in the visible spectrum, the rest being infra-red. Having at least some output energy in the visible spectrum has one advantage in allowing ready optical monitoring of progress. Also, optical clarity of the material when it softens may be better in the visible region than in the infra-red. So, at least significant (if not all should that be desired) visible spectrum heating could mean that, once softened, the heat take-up rate would be so low as to give indefinite time for the machine to be stopped in one place with the lamps running, but without melting the plastic.
  • a possible disadvantage in using predominantly white light could be reflectivity of whitish cold polyethylene slowing heating up, and requiring plural traversals over the lamps between the pipe and the reflector(s) in being absorbed in the polyethylene. This increases the heat loss in the reflector and may also mean that the lamps run hotter.
  • Lamp output frequencies could be tailored to some extent to suit any preferential colour absorption pattern of the particular plastics material to be heated.
  • Heat intensity from such as Ni-Chrome wires can be adjusted by controlling the current density, and therefore heat intensity in the wires, though Ni-Chrome wires should not be run white hot because they would either oxidise or melt at these temperatures.
  • tungsten elements in an inert atmosphere could be used, but probably not with significant operational advantage compared with generally more efficient halogen lamps.
  • the output will be spread out from infra-red into the visible. All that can be controlled is frequency where the peak output intensity will exist.
  • Preferred embodiments of this invention afford clean and dry, low cost, 100% no-dig, fast operation with progressive one-stage concurrent heating, forming and cooling; and no possibility of thermoplastic recovery either radial or longitudinal in a low residual stress true close-fit system not requiring grouting.
  • Preferred transparency onset features give intrinsic temperature regulation. No resins need be used, so storage life is indefinite,- and plant requirement is small size and minimal. No lead-in trenching is needed, nor modifications to existing manholes; and good dimples make lateral connections easy without excavation. Small heated volume/ area lead to low losses, and application is seen beyond polyethylene, basically only limited as to thermoplastic materials meeting requirements hereof, including as to inclusions for controlled heating alternatively to infra ⁇ red.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Toxicology (AREA)
  • Oral & Maxillofacial Surgery (AREA)
  • Lining Or Joining Of Plastics Or The Like (AREA)

Abstract

La présente invention concerne un procédé et un appareil destinés à la remise en forme d'éléments thermoplastiques à paroi, par exemple un tuyau (12) que l'on utilise pour rechemiser une conduite (20) usée. Ledit procédé consiste à chauffer ledit tuyau (12) de façon à ramollir toute l'épaisseur de sa paroi sans la faire fondre, et à remettre à la taille et à la forme souhaitée par l'application d'un fluide sous pression (16). Un rayonnement chauffant infrarouge (14) provoque, à la température de fusion cristalline ou à une température proche de celle-ci (en dessous de la température de fusion totale), un changement progressif du matériau thermoplastique (polyéthylène) allant de la transparence absorbante à la transparence utile, ce qui assure une autorégulation du chauffage ainsi que le changement de la mémoire géométrique d'origine du matériau thermoplastique. Une machine compacte préférée (10) combine un réseau d'éléments chauffants (22), une turbine à gaz sous pression (18) et un générateur de courant électrique (30) suivant un agencement coaxial et concentrique.
EP95941181A 1994-12-17 1995-12-18 Remise en forme d'elements thermoplastiques Withdrawn EP0797500A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
GBGB9425503.1A GB9425503D0 (en) 1994-12-17 1994-12-17 Method and apparatus for re-sizing thermoplastic pipes
GB9425503 1994-12-17
PCT/GB1995/002954 WO1996018493A1 (fr) 1994-12-17 1995-12-18 Remise en forme d'elements thermoplastiques

Publications (1)

Publication Number Publication Date
EP0797500A1 true EP0797500A1 (fr) 1997-10-01

Family

ID=10766106

Family Applications (1)

Application Number Title Priority Date Filing Date
EP95941181A Withdrawn EP0797500A1 (fr) 1994-12-17 1995-12-18 Remise en forme d'elements thermoplastiques

Country Status (5)

Country Link
EP (1) EP0797500A1 (fr)
AU (1) AU4266896A (fr)
CA (1) CA2208166A1 (fr)
GB (1) GB9425503D0 (fr)
WO (1) WO1996018493A1 (fr)

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB9614622D0 (en) * 1996-07-11 1996-09-04 British Gas Plc Lining a pipe
GB9626060D0 (en) * 1996-12-16 1997-02-05 United Utilities Plc Thermoplastic composite products
GB9712806D0 (en) 1997-06-19 1997-08-20 Rice Nigel L Apparatus and method for curing the lining of a pipeline
DE19733225C1 (de) * 1997-08-01 1998-08-27 Bkp Berolina Polyester Verfahren und Beschleunigungskörper zur Luftkühlung eines aushärtbaren Schlauchs
DE10260137B4 (de) 2002-12-20 2004-11-18 Schroeter, Johannes, Dr. Verfahren zur plastischen Verformung von Polymeren
GB0525505D0 (en) * 2005-12-14 2006-01-25 Chandler Brian B Sewer & water pipe lining
GB201103264D0 (en) * 2011-02-25 2011-04-13 Applied Felts Ltd Improvements in relation to lining passageways
GB2554431B (en) * 2016-09-27 2018-08-22 Aqualiner Ltd A pig for use in a system for lining ducts
EP3565999A1 (fr) * 2017-01-06 2019-11-13 Per Aarsleff A/S Ensemble de regarnissage de jonction entre un pipeline de dérivation et un pipeline principal, et de regarnissage d'une partie ou de l'ensemble du pipeline de dérivation
EA202190816A3 (ru) * 2017-12-01 2021-10-29 Пер Орслефф А/С Устройство и способ для отверждения вкладыша трубопровода
GB2571127B (en) 2018-02-19 2021-03-31 Aqualiner Ltd A pig for use in a system for lining ducts water or sewage pipes
US11391406B2 (en) 2019-11-11 2022-07-19 The Charles Machine Works, Inc. System and method for repairing an underground pipeline

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB8608805D0 (en) * 1986-04-11 1986-05-14 Du Pont Uk Thermoplastic polymer-lined pipe
JPS6416632A (en) * 1987-07-09 1989-01-20 Osaka Bosui Kensetsusha Kk Lining technique for pipeline
SE9100870D0 (sv) * 1991-03-22 1991-03-22 Inpipe Sweden Ab Foerfarande och anordning foer infodring av en helt eller delvis vaeggomsluten passage
JPH0752247A (ja) * 1993-08-13 1995-02-28 Furukawa Electric Co Ltd:The 既設管内面の内張り工法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO9618493A1 *

Also Published As

Publication number Publication date
WO1996018493A1 (fr) 1996-06-20
CA2208166A1 (fr) 1996-06-20
GB9425503D0 (en) 1995-02-15
AU4266896A (en) 1996-07-03

Similar Documents

Publication Publication Date Title
CA2088198C (fr) Methode de realisation d'un revetement interieur pour canalisations
WO1996018493A1 (fr) Remise en forme d'elements thermoplastiques
JP4750181B2 (ja) 部分的に浸水した地中パイプを巻回する装置および方法
JP4076188B2 (ja) 熱可塑性複合製品及びパイプ製作品を連結する方法
JPH0456738B2 (fr)
US5632952A (en) Method for lining lateral and main pipes
EP0241297A2 (fr) Fabrication d'un tuyau revêtu d'une matière polymère thermoplastique
EP0848659B1 (fr) Revetement de canalisation et son procede d'installation
US20170159869A1 (en) Improvements in or in relation to pipe liners and the installation thereof
US7306693B2 (en) Lining ducts
KR102062265B1 (ko) 팽창성 유지가 가능한 무수축 방식의 uv 조사장치 설치와 비굴착 상하수도 전체 보수 방법
JP3190688B2 (ja) パイプの内張り
KR100813860B1 (ko) 노후 수도관 내의 비굴착 갱생용 곡관부위 폴리에틸렌라이닝의 주름제거 방법 및 그 장치
US20020121338A1 (en) Method of lining pipes
RU2312767C2 (ru) Способ сварки термопластов и устройство для сварки термопластовых элементов
KR100217696B1 (ko) 노후관 보수용 라이너 및 라이너 피복방법
KR101955560B1 (ko) 확관기를 이용한 이중보온관 압출케이싱의 제조방법 및 그를 이용한 이중보온관 압출케이싱
JP2000515949A (ja) 地下のパイプラインのライニング構成
CN111963814A (zh) 管道非开挖修复方法
JPH11230412A (ja) 既設管路の更生方法
KR101972388B1 (ko) 부력체와 공압바를 이용한 이중보온관 압출케이싱의 제조방법 및 그를 이용한 이중보온관 압출케이싱
EP0958126A1 (fr) Structures stratifiees
AU715444B2 (en) Pipe liner and method of installation
JP2011083941A (ja) 既設管の更生方法及びライニング材の成形方法
JP2003314748A (ja) 更生管の管路更生工法

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 19970702

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB GR IE IT LI LU MC NL PT SE

17Q First examination report despatched

Effective date: 19990827

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20000108