This application claims the priority, under 35 U.S.C. § 119, of Austrian patent application A 797/2008, filed May 19, 2008; the prior application is herewith incorporated by reference in its entirety.
The invention relates to a method for quickly sealing a pipe section in a pipe by means of a hardenable, partially hardened, flat, in particular rectangular, insert or prepreg.
Methods of this type are used, in particular, for sealing pipes on the inside, preferably in waste water conduits.
A fundamental problem of the prior art is that sealing pipes is very time consuming and requires a great deal of work. Fleeces which are saturated in synthetic resin and then applied to a balloon and inserted into the pipe are often used in methods according to the prior art. In part, these steps are very unclean since the adhesive applied to the fleece sometimes continues to adhere to the balloon or drips from the fleece. It is not easily possible to install the fleece accurately.
It is accordingly an object of the invention to provide a method for sealing a pipe which overcomes the above-mentioned disadvantages of the heretofore-known devices and methods of this general type and which allows a pipe to be sealed quickly and efficiently.
With the foregoing and other objects in view there is provided, in accordance with the invention, a method of quickly sealing a pipe section in a pipe, the method which comprises the following method steps:
a) providing a substantially flat insert having an outer surface intended to adjoin a pipe for sealing the pipe, and having two mutually opposite end regions;
b) applying an adhesive to the outer surface of the insert;
c) overlapping the two opposite end regions of the insert to form an overlapping region, introducing adhesive into the overlapping region between the end regions, for forming the insert into a cylinder jacket or annular cylinder having a diameter substantially corresponding to an inside diameter of the pipe or slightly smaller than the inside diameter;
d) placing the insert onto an elongated, substantially cylindrical balloon, and maintaining a diameter of the balloon smaller than the inside diameter of the pipe;
e) placing a part of the insert against the balloon to cover a jacket surface continuously at least in a partial region thereof, and turning a remaining region of the insert, which does not adjoin the balloon, into a loop, and optionally pressing the loop against the outer surface of the insert;
f) inserting the balloon with the insert into the pipe and positioning the insert carried by the balloon at an area of the pipe section to be sealed; and
g) inflating the balloon, and pressing the insert against the inside wall of the pipe and hardening the adhesive.
In a preferred embodiment of the invention, the insert is a hardenable, partially hardened, insert sheet or prepreg. Further, the adhesive or glue may be applied over the entire outer surface of the insert. The placing step comprises slipping the insert over the balloon or wrapping and folding the insert about the balloon.
It was found to be advantageous that the adherence of the insert to the balloon or the loss of the adhesive prior to or during installation of the insert into the pipe is avoided by applying the adhesive from the outside. In addition, there is the advantage that the adhesive is distributed especially uniformly on the surface of the insert or pipe and a good adhesive effect of the insert to the pipe is obtained. Furthermore, wear of the insert on the pipe is prevented by the compact mounting of the insert during the installation.
An especially simple forming of an insert is made possible where the insert mat or prepreg is rectangular in its original form.
In accordance with an added feature of the invention, the overlapping region extends about 5% to 15% of the inner circumference of the pipe in peripheral direction of the formed cylindrical insert. The adhesion of the pipe insert to the balloon is thus improved during installation of the insert into the pipe.
In accordance with an additional feature of the invention, a layer of further adhesive is applied to the outer end regions of the insert in the area of the openings on the outer peripheral surfaces of the cylindrically shaped insert. This feature further improves the adhesion of the insert on the inner surface of the pipe. Furthermore, the density properties of the insert vis-à-vis the pipe are improved.
In accordance with another feature of the invention, the further adhesive is a water-hardening or waterproof epoxide resin. The time of the hardening can be preset especially accurately in this case.
In accordance with a further feature of the invention, the adhesive may include or consist of thermo-setting or UV-hardenable resin. This results in an especially advantageous adhesive effect of the insert on the pipe.
In accordance with again an added feature of the invention, the balloon is a UV-permeable balloon and the adhesive is irradiated and cured with UV light from inside the balloon. A simple hardening from the inside is made possible with these features.
In accordance with again a further feature of the invention, there is provided a partially hardened, flexible and/or deformable insert. Preferably, the insert is an extensible insert having a rubber-like consistency. This renders possible an especially simple mounting of the insert on the balloon and a good adaptation of the insert to the inside area of the pipe, including the resultant particularly effective sealing of the pipe section.
In accordance with yet an added feature of the invention, a protective foil may be wrapped around the insert attached to the balloon and provided with the adhesive, prior to insertion into the pipe. The foil is subsequently removed after the positioning of the insert and prior to inflating the balloon. Damage to the insert and/or loss of adhesive from the insert during installation of the insert into the pipe is prevented.
A uniform adhesive distribution on the surface is obtained especially easily when the above method steps are carried out in a sequence b), d), c), e), f), and g).
The step sequence d), b), c), e), f), and g), furthermore, enables especially drip-free installation of the insert into the pipe.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a method for sealing a pipe section, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
Referring now to the figures of the drawing in detail and first, particularly, to
The width of the end regions 11, 12 corresponds to the width of the overlapping region and corresponds to about 5% to 15% of the inner circumference of the pipe or 5% to 30% of the width b of the insert.
Furthermore, in
Preferably, this additional adhesive layer 51 can be formed with a hypoxide resin which is waterproof or which can be hardened (cured) in water.
The insert 1 is formed from a homogeneous material. Typically, the two surfaces of the insert 1 have the same surface quality. An adhesive 5 is applied to one of the two sides on the surface, in particular over the entire surface. That side to which the adhesive 5 has been applied will subsequently form the outer surface when the insert 1 is rolled up.
In one embodiment, the insert may be a prepreg, i.e., a pre-impregnated composite fiber product, typically in the form of a weave or unidirectional fibers pre-impregnated with partially cured resin.
The two aforementioned procedural steps, namely applying the adhesive 5 and rolling the rectangular insert 1 up to form a cylinder can basically be carried out in either desired sequence.
The inserted insert 1 is flexible and/or deformable, in particular extensible, and has a rubbery consistency; after hardening, or curing, it is rigidly secured with the inside wall of the pipe.
A preferred embodiment of the method according to the invention is in that the insert 1 provided with adhesive 5 and applied to the balloon 4 is surrounded with a protective foil 7 prior to installation in the pipe 2. A portion of the foil 7 is diagrammatically illustrated in
As already mentioned, the chronological sequence of the individual procedural steps is unimportant and what is essential is that the application of the adhesive, making the opposite end regions 11, 12 coincide, affixing the insert 1 to the balloon 4 and forming the loop 16 prior to inserting the balloon 4 with the insert 1 into the pipe 2 are carried out. The balloon 4 is inflated last. In this connection, it was found to be especially advantageous to first apply the adhesive 5 to the surface of the insert 1, then affix the insert 1 to the balloon 4, then make the two opposite end regions 11, 12 coincide and subsequently place the insert 1 on the balloon 4 and form a loop 16 from the non-adjoining areas.
Furthermore, it is possible to interchange the first two procedural steps, in this case, the insert 1 is first affixed to the balloon 4 and then the adhesive is applied to the outer surface of the insert 1.
To prevent relative slippage between the two end regions 11, 12 during inflation of the balloon, it can be provided that adhesive 5 be inserted in the overlapping region 13 between the two end regions 11, 12. Furthermore, to ensure additional mechanical stability, a cog-like mounting element or a cog 6 can be used which has extensions or pins 61 toward two opposite directions. The extensions or pins penetrate into the insert 1 during pressure impacts. The pins 61 thereby have a length of up to 100% of the thickness of the insert 1. Furthermore, the cog comprises a body or a housing 62 from which the pins 61 project in opposite directions. The length of the body 62 of the cog 6 thereby corresponds to the length/of the insert 1. The width of the body 62 is less than the width of the overlapping region 13 and is preferably in the range of between 40% and 80% of the width of the region. The thickness of the body 62 is to be kept as small as possible and is about in the range of 5% to up to 20% of the thickness of the insert 1. This is necessary as, otherwise, the thickness of the insert is very large in the area of the overlapping region 13 and the radius of the pipe 2 would narrow non-symmetrically.
In particular, the adhesive 5 is formed with UV-hardenable (i.e., UV-curable) resin or consists of UV-hardenable resin. In this case, a UV-permeable balloon 4 is used. After positioning the insert 1, the adhesive 5 is irradiated by means of UV light from inside the balloon 4 and hardened.
The object of proceeding in this manner is to reduce the time required for the hardening and to specifically control the time of the hardening of the resin. A further object is to allow the resin to harden in the shortest time possible, whereby the resin should, if possible, not harden prior to being applied to the pipe insert.
The invention enables an especially accurate control over the hardening process, whereby the hardening can be monitored with little human interaction by means of a radio remote control with simultaneous viewing and by means of a camera with radio transmission. The time of the hardening of the resin can thereby be very precisely set. The insert can be exactly positioned and the hardening process subsequently controlled by a camera located in the area of the balloon.
Number | Date | Country | Kind |
---|---|---|---|
A-797/2008 | May 2008 | AT | national |