PROCESS FOR PRODUCING A FLEXIBLE TUBE FOR LINING PIPES, CHANNELS OR THE LIKE

PROCEDE DE PRODUCTION D'UN FLEXIBLE SERVANT A GARNIR L'INTERIEUR DE CANALISATIONS, DE CANAUX OU SIMILAIRES

English Abstract

The invention relates to a process for producing a flexible tube for lining
pipes, channels or the like, with an outer woven, layered or knitted glass-
fibre web, a voluminous glass-fibre product mat and a covering inner woven,
layered or knitted glass-fibre web, while the combined web thus formed is
shaped into a flexible tube and the combined web edges are bonded together, in
which the outer woven, layered or knitted glass-fibre web consists of a cut
fibre mat which is bonded to the voluminous glass-fibre product, which
consists of a needle felt, whereby the inner glass-fibre knitted web consists
of a cut fibre mat bonded with a voluminous glass-fibre product in the form of
a needle felt.

French Abstract

L'invention concerne un procédé permettant de produire un flexible destiné à garnir l'intérieur de canalisations, de canaux ou similaires, qui comprend une bande extérieure de tissu ou de textile tricoté, en filaments de fibres de verre, un mat volumineux de produit en fibres de verre et une bande intérieure de recouvrement en tissu ou en textile tricoté. La bande combinée ainsi obtenue est traitée de manière à se présenter sous forme de flexible et les bords de ladite bande combinée sont reliés les uns aux autres. La bande extérieure de tissu ou de textile en fibres de verre se compose d'un mat de fibres découpées, lié au produit en fibres de verre volumineux, et le mat volumineux de produit en fibres de verre est constitué de feutre aiguilleté. La bande intérieure en tissu ou en textile tricoté se compose d'un mat de fibres découpées, lié à un produit en fibres de verre volumineux se présentant sous forme de feutre aiguilleté.

Claims

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Claims:
1. A process for production of a hose for inlining
pipelines, ducts or the like, with an outer woven,
laid or knitted sheet formed from glass fibre
filaments, a lofty glass fibre product mat and a
covering inner woven, laid or knitted sheet formed
from glass fibre filaments, by forming the resulting
combination sheet into a hose and joining the
combination sheet edges together, characterized in that
the finished hose is saturated with a low-viscosity
resin and the outer layer is pregelled to prevent
any escape of resin.
2. A process according to Claim 1, characterized in
that the low-viscose resin is pregelled by UV
irradiation.
3. A process according to Claim 1, characterized in
that a sheet of web composed of synthetic fibres is
disposed on the inner surface of the combination
sheet for the hose to be formed.
4. A process according to Claim 3, characterized in
that the web is secured to the inwardly directed
face of the inner glass fibre web, glass fibre lay
or glass fibre knit sheet.
5. A process according to Claim 4, characterized in
that the web is secured to the inwardly directed
face of the inner glass fibre sheet by adhering.
6. A process according to Claim 4, characterized in
that the web is needled to the inwardly directed
face of the inner glass fibre sheet.

Description

CA 02206639 1997-06-02
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PCT/DE 95/01208
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Firma SAERTEX Wagener GmbH ~ Co. KG,
Industriestr. 9, 48369 Saerbeck
'IProcess for production of a hose for inlininq ~ipe-
lines, ducts or the like'l
The invention relates to a process for production of a
hose for inlining pipelines, ducts or the like as per the
preamble of the main claim.
DE 38 19 657 C1 discloses a congeneric process wherein a
felt mat formed from glass fibres is placed between woven
or knitted sheets formed from glass fibre filaments, the
felt mat is then joined to the woven or knitted sheets by
knitting, and this combination sheet is formed into a
hose. Here the woven or knitted sheets can be joined to
the needlefelt sheet by lamination, and the sheet edges
can be butt-jointed and joined together by sewing or
joined together by felting.
DE 38 19 657 further discloses impregnating the resulting
hose with synthetic resin and pulling it into the duct
pipe to be repaired close to the inner surface of the
pipe and then curing. The cured resin contributes appre-
ciably to the strength of the hose. Since, however, the
resin must not escape after impregnation and the impreg-
nation is effected for example outside the duct and thehose is only pulled later into the pipe to be repaired,
it has been attempted to increase the viscosity of the
resin by adding appropriate thixotropicizers and/or
thickeners.
However, this procedure has the considerable disadvantage
that it appreciably slows down the rate of impregnation
and leads to incomplete wetting of the individual fibres,
in which connection it should further be borne in mind
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that the thickener is not effective at once. If the
resulting hose is then wound up or folded, the resin is
squeezed out of the fold regions, and impregnation is
non-uniform, viewed over the entire length of the hose.
What is more, the impregnating liquor is thickened, so
that it lacks utility after a short time.
It is an object of this invention to provide a remedy
here, and it is proposed that the hose be impregnated by
using a resin of low viscosity, which disperses very
readily within the entire sandwich structure, good
dispersion being achieved within the needlefelt in
particular. A pregelling of the outer layer, for example
by means of W radiation, ensures the formation, on the
outer layer, of a barrier layer, so that the resin cannot
escape.
In relation to the later, final curing which takes place
within a duct or pipe or the like, this layer ensures
that complete curing will be achieved even in the regions
which are in contact with the cold duct or pipe walls and
which, in the prior art, cannot be adequately cured
because of the heat loss.
According to a further proposal of the invention, a web
is disposed on the inner surface of the resulting hose to
create an additional barrier layer and hence, after
curing, a resin-rich zone. This resin-rich, cured zone is
particularly important for aggressive and abrasive media.
In addition, the low-viscosity resin expels the air from
the entire combination mat, i.e. the sandwich structure,
and the web layer deaerates very efficiently and thor-
oughly in the process.
This arrangement of the invention ensures better wettingof the reinforcing material at lower pressures.
The inclusion of a web, which can also be adhered in
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place, has the inward effect that a faster performance of
the work can talce place and a better venting of the rooms
takes place.
During the creating of the sandwich structure, a film,
preferably a film hose which has been laid flat, is
placed into the interior of the structure to permit later
calibration.
The use of the sandwich structure of the invention is of
advantage in sewage ducts. The structure of this inven-
tion is similarly useful for lining any possible pipesystems, for example pressure lines, industrial lines and
microtunnels.
It is further pointed out that the sandwich product of
the invention is further suitable for use as an inner
pipe, in which case a monitoring space is created between
the inner pipe and the outer pipe, said monitoring space
being suitable for having appropriate measuring equipment
connected to it to detect leakages from the inner pipe.
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