Tubular liner having an outer tubular film connected in an overlapping manner by adhesive tape, for lining pipelines, and method for manufacturing same

Abstract

A tubular liner for the lining of pipelines has an inner tubular film, a layer of fibrous material arranged on the inner tubular film, and an outer tubular film which is arranged on the outer side of the fibrous material and is impermeable to UV light. The tubular liner is distinguished in that the outer tubular film has a radially inward peripheral portion and a second peripheral portion bearing on the outer side of the first peripheral portion in an overlapping region. The peripheral portions are connected to one another by an adhesive tape which extends across the longitudinal direction of the tubular liner. A method is also provided for manufacturing such a tubular liner.

Claims

1. A tubular liner for lining of pipelines, the tubular liner comprising: an inner tubular film; a layer of fibrous material disposed on said inner tubular film and having an outer side; adhesive tape; and an outer tubular film disposed on said outer side of said layer of fibrous material and being impermeable to UV light, said outer tubular film having peripheral portions including a radially inward first peripheral portion and a radially outward second peripheral portion bearing on an outer side of said radially inward first peripheral portion in an overlapping region, said peripheral portions connected to one another by said adhesive tape extending across a longitudinal direction of the tubular liner, said outer tubular film having a first and a second circumferential portion, wherein on said first circumferential portion said radially inward first peripheral portion is formed and includes first and second inward first peripheral portions, corresponding to first and second outward peripheral portions of said second radially outward peripheral portion formed on said second circumferential portion, which overlap in first and second overlapping regions and are connected to one another by said adhesive tape extending and being adhesively attached in the longitudinal direction.

2. The tubular liner according to claim 1, wherein said first circumferential portion has a circumferential width which is between 60 and 90% of a circumferential width of said second circumferential portion.

3. The tubular liner according to claim 1, wherein said first circumferential portion and said second circumferential portion are connected to one another by a single strip of said adhesive tape that has a same or a larger width than said first circumferential portion and extends across said first and second overlapping regions.

4. The tubular liner according to claim 1, wherein said adhesive tape contains first and second adhesive portions as well as a tensioning portion which connects said first and second adhesive portions to one another and which is disposed above said first and second overlapping regions and said adhesive tape is composed of a thermoplastic material which, under an influence of heat, contracts in a circumferential direction in such a manner that said first adhesive portion is moved in a direction of said second adhesive portion.

5. The tubular liner according to claim 1, further comprising a cooled hot-melt adhesive, said peripheral portions, in said first and second overlapping regions, are additionally connected to one another by at least one layer of said cooled hot-melt adhesive, which extends in the longitudinal direction of the tubular liner.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

(1) FIG. 1 is a diagrammatic cross-sectional view through a tubular liner according to the invention, during manufacturing thereof on an indicated mandrel, in which tubular liner an outer tubular film is assembled from a single infed film web;

(2) FIG. 2A is a diagrammatic cross-sectional view of a second embodiment of the invention, in which the outer tubular film contains a first and a second circumferential portion which are connected to one another by adhesively bonding a first and second infed film by a single strip of adhesive tape;

(3) FIG. 2B is a diagrammatic perspective view onto the tubular liner according to FIG. 2A, having an additional longitudinal pull strap;

(4) FIG. 2C is a diagrammatic cross-sectional view of a further embodiment of the tubular liner according to the invention, in which the outer tubular film contains a first and second circumferential portion, the peripheral regions of which are in each case connected to one another by an adhesive tape rolled thereon;

(5) FIG. 2D is a diagrammatic, perspective view onto the tubular liner according to FIG. 2C; and

(6) FIG. 3 is a diagrammatic, lateral view of a tubular liner according to the invention, which is continuously produced on a mandrel, having a first and/or a second circumferential portion which is/are infed in the shape of film webs.

DETAILED DESCRIPTION OF THE INVENTION

(7) Referring now to the figures of the drawings in detail and first, particularly to FIG. 1 thereof, there is shown a tubular liner 1 which has an inner tubular film 2 on which at least one layer of fibrous material 4, in particular of fibrous tapes 4a which are impregnated with a reactive resin which is curable by UV light, is arranged. As can be further obtained from FIG. 3 which shows the manufacturing method for the tubular liner 1 according to the invention, the fibrous tapes 4a are wound onto the inner tubular film 2 by a winding device which has a mandrel 6, as is described in international patent disclosure WO 007/73692, for example. On the outer side of the layer of fibrous material 4 an outer tubular film 8 which, in the embodiment shown in FIG. 1, is composed of a single plastic film which is impermeable to UV light and which is infed as a one-part endless film web on the lower side and is formed by folding over the film peripheries onto the upper side of the fibrous material, is arranged. Here, in an overlapping region 12, a radially inward peripheral portion 10b comes to lie on a radially outward peripheral portion 10a. In order to subsequently connect the two peripheral portions 10a and 10b so as to form a circumferentially closed outer tubular film 8, a one-sided adhesive tape 13 is adhesively attached from above, preferably by half, onto the two mutually overlapping peripheral portions, such that a seam which is similar to an overlapping seam and which has high tensile strength in relation to forces which act in the circumferential direction of the outer tubular film is created. In order to fold the plastic film from which the outer tubular film 8 is formed around the peripheral portions of the tube of fibrous material 4 that is sometimes still guided on the mandrel 6, revolving brushing units 14a and 14b which are schematically indicated in FIG. 1 and which may have, for example, polyamide bristles which, proceeding from the peripheries, brush across the upper side of the folded-over film web toward the overlapping region 12, are preferably provided. The revolving speed of the two brush belts 14a, 14b as well as their angle in relation to the conveying direction V of the outer tubular film here is preferably such that air inclusions located under the folded-over film web are brushed out toward the overlapping region, such that the film web of the outer tubular film 8 bears in a tight manner on the outer side of the fibrous material 4.

(8) In the embodiment of the invention shown in FIGS. 2A and 2B the tubular liner 8 according to the invention contains a first circumferential portion 8a which is preferably infed as an endless film web from above onto the tube of fibrous material 4, that has been previously continuously produced and that is moved, proceeding from the mandrel 6, at its indexing speed V over a support surface 16 which is fixed to the frame. The film web of the first circumferential portion 8a here may be unrolled from a roll 18a, for example, as is indicated in FIG. 3.

(9) The outer tubular film 8 furthermore contains a second circumferential portion 8b which is preferably unrolled from a second roll 18b which is located on the lower side of the infed tube of fibrous material 4. In order to fold the two peripheral portions of the lower film web 8b around the tube of fibrous material 4 here, the peripheral portions are acted upon in an upward direction by way of a guide unit (not shown in more detail), for example a known shaping shoulder or else by two brushing units 14a and 14b indicated in FIG. 2A and FIG. 3. On account thereof the right-hand, radially inward peripheral portion 10b and left-hand, radially inward peripheral portion 10b (both in FIG. 2A) of the second circumferential portion 8b come to lie on the in each case radially outward peripheral portion 10a of the first circumferential portion 8a. Subsequently, a single strip of adhesive tape 13 is adhesively bonded onto the upper side of the two overlapping regions 12 being created, the strip of adhesive tape having such a width that the first circumferential portion 8a is completely spanned thereby, covering here the peripheral portions, lying on the top, of the second circumferential portion, that is to say of the second infed film web 8b, by, for example, 1 to 5 centimeters.

(10) In order to prevent the screw-like windings of the tube of fibrous tapes 4a wound screw-like in an overlapping manner from falling apart during insertion of the completed tubular liner 1 into a duct (not shown in more detail), a longitudinal pull strap 17, for example a tape of fiberglass fabric, which is schematically indicated only in FIGS. 2B and 2D and which, prior to infeeding of the film web for the first circumferential portion 8a, is unrolled onto the upper side of the tube of fibrous material 4 via an additional roller, is preferably arranged below the first circumferential portion 8a of the outer tubular film 8. For reasons of clarity, the longitudinal pull strap is not shown in the remaining figures.

(11) The web-like material for forming the first and the second circumferential portions 8a, 8b, on the inner side facing the fibrous material 4, is preferably provided with a non-woven material which, preferably as a polyester non-woven material, is already laminated onto the inner side of the first and second circumferential portions 8a, 8b during manufacturing of the film web. On account of the brushing units 14a, 14b which approach the upper side of the second circumferential portion 8b and which optionally may additionally also approach the lower side of the first circumferential portion and in each case brush across the latter proceeding from the center toward the lateral peripheries, in conjunction with a non-woven layer which is arranged on the inner side of the film material of the first and second circumferential portions, a taut and bubble-free bearing of the film material on the layer of fibrous material 4 that is impregnated with liquid reactive resin can be obtained.

(12) According to the embodiment of the invention shown in FIGS. 2C and 2D, it is alternatively possible to use two narrow strips of adhesive tape 13 instead of a preferably employed single wide strip of adhesive tape which spans the entire free portion between the two outward peripheral portions of the second circumferential portion, which two narrow strips of adhesive tape, similarly to the embodiment shown in FIG. 1, preferably only cover the two peripheral regions by half and are infed as endless adhesive-tape material from a roll 20 in the same manner as the film webs for the two circumferential portions 8a, 8b.

(13) The following is a summary list of reference numerals and the corresponding structure used in the above description of the invention: 1 Tubular liner according to the invention 2 Inner tubular film 4 Layer of resin-impregnated fibrous material 4a Fibrous tape 6 Winding device/mandrel 8 Outer tubular film 8a First circumferential portion 8b Second circumferential portion 10a Radially inward peripheral portion 10b Radially outward peripheral portion 12 Overlap region 13 Adhesive tape 14a First brushing unit 14b Second brushing unit 16 Support surface 17 Longitudinal pull strap 18a Roll having film web for the first circumferential portion 18b Roll having film web for the second circumferential portion 20 Roll of adhesive tape V Indexing speed