EP1397609A1 - Procede de fabrication de tuyaux isoles avec de la mousse - Google Patents

Procede de fabrication de tuyaux isoles avec de la mousse

Info

Publication number
EP1397609A1
EP1397609A1 EP02708251A EP02708251A EP1397609A1 EP 1397609 A1 EP1397609 A1 EP 1397609A1 EP 02708251 A EP02708251 A EP 02708251A EP 02708251 A EP02708251 A EP 02708251A EP 1397609 A1 EP1397609 A1 EP 1397609A1
Authority
EP
European Patent Office
Prior art keywords
diffusion barrier
foam
aluminium
foaming
foil
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Withdrawn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
EP02708251A
Other languages
German (de)
English (en)
Inventor
Lars Valentin Nielsen
Per Poulsen
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.)
Logstor AS
Original Assignee
Alstom Power Flowsystems AS
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 Alstom Power Flowsystems AS filed Critical Alstom Power Flowsystems AS
Publication of EP1397609A1 publication Critical patent/EP1397609A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • 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
    • B29C44/00—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles
    • B29C44/02—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles for articles of definite length, i.e. discrete articles
    • B29C44/12—Incorporating or moulding on preformed parts, e.g. inserts or reinforcements
    • B29C44/1228—Joining preformed parts by the expanding material
    • B29C44/1242—Joining preformed parts by the expanding material the preformed parts being concentric
    • 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
    • B29C44/00—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles
    • B29C44/34—Auxiliary operations
    • B29C44/60—Measuring, controlling or regulating

Definitions

  • the invention relates to a process for the manufacture of foam-insulated pipes of the kind which comprises an inner pressure pipe, a foam coat, at least one diffusion barrier comprising aluminium which is formed in tubular shape, and a plastic outer casing extruded around said components.
  • the invention furthermore relates to a foil material which is suitable for performing the process.
  • Such foam-insulated pipes are manufactured in great quantity for the use in district heating, and their good insulating properties are to a large extent caused by the gas which is present in the small cells of the foam and which has been used in the foaming process. Due to diffusion, with time there will be an exchange of this gas for atmospheric air which has a considerably lower thermal insulation, or water vapour may appear in adverse conditions. This exchange takes place over a period of years, but it is still a short time compared to the lifetime expected for a district heating installation.
  • Constructions which have an integrated diffusion barrier in a foam- insulated pipe of this kind, e.g. described in EP 84 088 and DE 33 07 865.
  • the diffusion barrier consists of aluminium laminated with plastic.
  • the manufacture is continuous, in that the inner pressure pipe is taken through a number of stations where the various layers are created. It is desired that there shall be a good adherence between the pressure pipe and the foam, between the foam and the diffusion barrier, and between the diffusion barrier and the outer casing.
  • the foaming is performed continuously by the supply of raw materials from a mixing station (e.g. isocyanate/polyol and catalyst), in order that the foaming occurs between the pressure pipe and the diffusion barrier which is held in a tubular shape with overlapping.
  • a mixing station e.g. isocyanate/polyol and catalyst
  • the diffusion barrier is provided in the form of a strip which has a width corresponding to the inner perimeter of the outer casing, with additional material for overlapping, and it is formed axially.
  • the diffusion barrier is wound helically.
  • the diffusion barrier consists of aluminium foil which is laminated to plastic on at least one side. After the foaming the foam-filled tubular diffusion barrier with the insulation and pressure pipe inside are taken through a station for extrusion of the outer casing.
  • Control of the quality of the foaming may occur in several ways, e.g. by means of ultrasound, but this can only be performed further along the manufacturing process, where the foam has hardened, which means that fast-acting control to obtain correct pore dimensions and foam adherence is impossible. This is a problem which may i.a. cause rejection and cutting of pipe lengths in unsuitable locations, because sections of insulated pipe with a lower quality must be rejected.
  • the diffusion barrier is a layer of aluminium laminated to plastic, in which the aluminium layer at regular intervals has been given a shape so that a transparent area is generated in the formed diffusion barrier tube, said area permitting inspection of the foaming process inside the diffusion barrier tube.
  • the transparent areas permit the inspection of the foaming process, either by means of the experienced eye of the operator, or by means of image analysis performed on a video image of the process.
  • the result is used for controlling the supply of foam per unit of time. Thereby a considerable certainty for correct pore dimensions and strength of the foam is obtained, particularly in connection with the start of production.
  • the overlapping in the tubular diffusion barrier is provided with a further aluminium-covered adhesive foil which provides the requisite diffusion barrier action at least in the transparent area.
  • the foil may e.g. obtain its adhesion by welding of the laminated plastic layers.
  • the inspection occurs by means of a video camera which provides an electronic image of the foaming.
  • the image is analysed in an image analysis unit and sorted into a classification for foaming quality according to pre-defined criteria.
  • a foaming qualtity moving towards a reduction of quality causes a regulation of the amount of foam per time unit until the desired quality is reached.
  • the diffusion barrier has a longitudinal three-layer construction with an aluminium foil in the middle, with a thermoplastic layer which is adapted to weld to the surrounding outer casing during its extrusion, and a thermoplastic layer which is adapted to adhere effectively to the foamed material, whereby the aluminium has a full width regularly interrupted by areas having a reduced width.
  • Fig. 1 schematically shows a plant for continuous manufacture of insulated pipes
  • Fig. 2 schematically shows the foaming along a pipe during production
  • Fig. 3 a and 3b schematically show the generation of a window by means of a transparent area
  • Fig. 4 shows inspection by means of video and image analysis.
  • Fig. 1 is seen an industrial plant which is essentially intended for continuous production, apart from the fact that pressure pipes are brought to the plant at one end, and are welded end-to-end to unlimited length, and that foil material is brought on rolls which have to be renewed, and that plastic granules have to be provided for the outer casing.
  • the finished insulated pressure pipes must be wound on storage devices with a limited length, which means that the unbroken pipe must be cut when a storage device is full.
  • the plant comprises an uncoiling station 1 for an inner pressure pipe 2 which is taken through a straightening apparatus 3 with its own control system 4 for controlling the tension of the inner pipe.
  • a foaming station 5 is provided with foam from a foam generator 6 via a foam supply line 6a, which feeds into a foil L taken from a foil supply roll 7 and folded into a tubular shape.
  • An observation location O enables inspection according to the invention (indicated by an eye), which controls the amount of foam supplied.
  • the pressure pipe 2 surrounded by foam in the foil tube is pulled through a foam hardening zone 8 by means of pulling apparatus 9.
  • a strip of adhesive foil of predetermined length is supplied from a supply roll 10 and is adhered to pre-determined areas of the foil tube at F.
  • An extuder 11 creates the plastic outer casing for the insulated pipe. This casing is cooled in a cooling zone 12, the velocity of the pipe is measured at 13, and outer markings are printed or stamped onto the casing at 14.
  • the completed insulated pipe is pulled forward by means of further pulling apparatus 15 and passed to a rotated take-up reel 17 via a cutting station 16, which cuts the pipe when a reel is full.
  • a new reel 17 is fitted, and the pulling apparatus 15 provides pipe to wind onto the empty reel.
  • the plant is controlled by a central controller 18, which communicates with a control 19 for the foaming apparatus, in particular the foam generator 6.
  • Fig. 2 it is shown schematically, how a sloping foam front is created, because the foam is at a low level initially and expands and fills the space between the surrounding foil L and the inner pressure pipe.
  • the foam S is supplied in a controlled manner through a supply line immediately before the overlapping between the two sides of the foil strip takes place. This overlapping is created by the guide rollers r which are shown schematically. Because the surrounding foil and the inner pressure pipe are pulled away in time with the foaming, any location along the pipe in the range of the foaming will have a particular foam level.
  • the foam By means of the invention it has become possible to observe the foam when it has reached its maximum expansion and to evaluate its quality immediately before it hardens. This may advantageously be performed in the area designated O. Properties, such as pore dimensions, pore unifority, and colour are evaluated.
  • the window used consists of two plastic layers only (polyethylene on the outside and polyester on the inside), the diffusion barrier is not sufficient in this area, and the foil tube is hence provided with a strip of adhesive foil laminated with aluminium in the areas of the windows, and with a suitable overlapping.
  • the foil application station is shown at F in Fig. 1.
  • Fig. 3 a a strip which consists of a layer M of aluminium, which has a plastic foil on either side as described above.
  • This laminate has an overlapping part K, and the aluminium layer has areas of reduced width, whereby an area P is obtained which consists of the two outer plastic layers, without aluminium.
  • Fig. 3b it is further seen how the foil, which is folded into a cylindrical shape, creates an oblong window N, due to the particular shape of the aluminium layer, through which window the inspection may occur.
  • Such areas P may be provided at regular intervals in order that the production may be inspected.
  • Fig. 4 is shown how a stereoscopic video camera 20 with a closeup lens focuses on an area immediately inside the foil window N, and that the video signals processed in signal processing means 21 in in order that the contrast and edge definition are improved.
  • An image processing programme extracts information about the mean pore dimensions and the spread in a further unit 22, as well as the colour type and distribution, and as a result of this the amount of foam supplied at the input end of the foaming station is increased or decreased by providing a control signal to the foam control unit 19 or directly to the foam generator 6.
  • the foam properties become self-regulating.
  • any metal-based diffusion barrier that is not transparent may be used, and the advantages of the invention obtained by means of a window will be as described.

Landscapes

  • Lining Or Joining Of Plastics Or The Like (AREA)

Abstract

Un tuyau isolé avec de la mousse et enchâssé dans du polyéthylène peut s'utiliser, par exemple, dans le chauffage à distance; il est fabriqué selon un procédé en continu par la formation d'une mousse entre un tube à barrière de diffusion et le tube de pression. La qualité de moussage est vérifiée de façon intermittente par l'inspection de la mousse à travers une partie transparente du tuyau à barrière de diffusion auquel on confère par la suite des propriétés de barrière de diffusion au moyen d'un feuil d'aluminium adhésif laminé.
EP02708251A 2001-03-14 2002-03-14 Procede de fabrication de tuyaux isoles avec de la mousse Withdrawn EP1397609A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DKPA200100440 2001-03-14
DK200100440 2001-03-14
PCT/DK2002/000172 WO2002073083A1 (fr) 2001-03-14 2002-03-14 Procede de fabrication de tuyaux isoles avec de la mousse

Publications (1)

Publication Number Publication Date
EP1397609A1 true EP1397609A1 (fr) 2004-03-17

Family

ID=8160369

Family Applications (1)

Application Number Title Priority Date Filing Date
EP02708251A Withdrawn EP1397609A1 (fr) 2001-03-14 2002-03-14 Procede de fabrication de tuyaux isoles avec de la mousse

Country Status (2)

Country Link
EP (1) EP1397609A1 (fr)
WO (1) WO2002073083A1 (fr)

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2613741A1 (de) * 1976-03-31 1977-10-13 Kabel Metallwerke Ghh Verfahren zur kontinuierlichen herstellung waerme- und schallisolierter leitungsrohre
DE3200441A1 (de) * 1982-01-09 1983-08-04 Felten & Guilleaume Energietechnik GmbH, 5000 Köln Flexibles fernwaermeleitungs-verbundrohr
DE3307865A1 (de) * 1983-03-05 1984-09-06 kabelmetal electro GmbH, 3000 Hannover Waermeisoliertes leitungsrohr und verfahren zu seiner herstellung

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO02073083A1 *

Also Published As

Publication number Publication date
WO2002073083A1 (fr) 2002-09-19

Similar Documents

Publication Publication Date Title
EP0897788B1 (fr) Procédé pour la fabrication d'un tuyau isolé thermiquement
JP4023771B2 (ja) 同軸ケーブルおよびその製造法
EP1840444B1 (fr) Procédé pour la production d'un manteau pour conduite isolée thermiquement
JP4990857B2 (ja) 複合材料
WO1997045843A2 (fr) Cable coaxial
EP1030776A1 (fr) Produits en forme de spirale et procede de fabrication
DE19961306A1 (de) Extrusionsvorrichtung
KR20210006898A (ko) 열적으로 절연된 파이프를 제조하기 위한 방법 및 장치
EA013854B1 (ru) Способ и устройство для изготовления удлиненного изделия и изделие
KR102308367B1 (ko) 압출 동시 코팅형 일체 융착식 친환경 부표와 그 제조방법
WO2002073083A1 (fr) Procede de fabrication de tuyaux isoles avec de la mousse
AT398053B (de) Verfahren und rohrverbindungsstück zur kontinuierlichen herstellung umschäumter, thermisch isolierter leitungsrohre
WO2021170264A1 (fr) Tube de conduite isolé thermiquement
JPH1190972A (ja) 断熱ホースの製造方法
EP1640652B1 (fr) Tuyau souple thermiquement isolé, procédé et outillage de fabrication d'un tel tuyau
EP0418760A3 (en) Method of manufacturing a large calibre plastic pipe and extruder for carrying out said method
EP2964996A1 (fr) Tuyau ondulé à isolation thermique
US8747714B2 (en) Method of manufacturing mesh-reinforced thermoplastic membranes
EP2586602B1 (fr) Procédé de fabrication d'un tube flexible à isolation thermique
WO1984003066A1 (fr) Procede de fabrication d'une gaine ou d'un conduit d'isolation thermique pour un ou plusieurs tuyaux
AU2007293923B2 (en) Method for the production of a cylindrical, strand-shaped part
JP5449220B2 (ja) 断熱パイプカバー
EP0008689A1 (fr) Procédé et dispositif pour fabriquer des feuilles en mousse thermoplastique
EP1520675B1 (fr) Procédé de fabrication de tuyaux isolés par de la mousse
DE102016115968B4 (de) Verfahren zum Herstellen eines Streifens für ein Isolierrohr eines Isolierverbundrohrs sowie ein derartiges Isolierverbundrohr

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: 20031014

AK Designated contracting states

Kind code of ref document: A1

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

AX Request for extension of the european patent

Extension state: AL LT LV MK RO SI

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

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

Free format text: STATUS: THE APPLICATION HAS BEEN WITHDRAWN

18W Application withdrawn

Effective date: 20080407