Device for works in for instance pipelines This invention relates to a device according to the introductory part of claim 1.
When for instance relining leaking sewers or water pipelines located in the ground there is a need of appropriate means for making the relining work. Relining means that an inner pipe, a so-called lining pipe, is introduced into the leaking pipeline, which pipe is intended to take over the function of the leaking outer pipe so that the leaking pipeline again becomes in working order. The relining work is a very profitable method of repair since it is not necessary to make large digging works in the ground in connection with the repair of the leaking pipe.
The purpose of the present invention is to bring about an extraordinarily useful device for works in for instance pipelines, and this purpose is achieved by the fact that the device has the characerizing features mentioned in the claims.
The device according to the invention can be introduced to a desired position into for instance a pipe and is thereafter remotely activated so that during a desired time period it is fixed in this position inside the pipe. The device is designed in that way that it can be docked together with a lot of different fittings in connection with works in pipelines. In a special embodiment the device may also be used as a sealing plug. There is also a possibility to connect a number of devices according to the invention with one another in series to achieve a greater fixation force in relation to a surrounding pipe. Embodiments of the invention will be more closely described in the following with reference to the accompanying drawings, in which Fig 1 shows the device
according to the invention in a longitudinal view, partly cut away; Fig 2 shows the device in an end view according to the arrow II of Fig 1, the device being in an expanded position; Fig 3 shows the device in a section along the line III-III of Fig 1; Fig 4 shows the device in a section along the line IV-IV of Fig 1; Fig 5 and 6 schematically show the device in a longitudinal section, the gripping means of the device in Fig 5 being located in an inactive position and in Fig 6 being located in an active position; Fig 7 schematically shows how the device can be changed in order to be suited for a larger pipe diametre; and Fig 8-10 show in section examples of alternative gripping means. As is best apparent of Fig 1 the device 1 according to the invention is built up around a centre pipe 2 which also functions as a pipe for compressed air. The centre pipe 2 has two end collars 3. The end collar 3 is built up by a centre sleeve 4, a ring 5 with a flange 6 and a cylinder formed part 7, the centre sleeve 4 and the ring 5 being connected to each other by means of arms 8 arranged like spokes.
The device 1 further comprises an additional pipe 9 surrounding the centre pipe 2 and having openings 10 and 11. Outside the additional pipe 9 there are arranged a number of module rings 12-14. Between the module rings there are arranged rings 15 of swelling body. The rings 15 of swelling body are made of an elastic material, for instance rubber, and are on their outer jacket-surface provided with a recess 16 extending round the rings 15 for taking up gripping means in the form of bent gripping blocks 17, which are kept together by a ring 18 of an elastic material, for instance a so-called 0-ring. Between the ring 15 of swelling body and the gripping blocks 17 there is suitably arranged an elastic, annular band 19 for adjustment and reinforcement reasons.
In this connection should be mentioned that it is advantageous to arrange the end surfaces 20 of the rings 15 of swelling body, as is apparent from Fig 1, somewhat conical, also the contact surfaces of the module rings 12-14 towards the rings of swelling body being made with the corresponding conicity. The purpose of this measure is to keep an effective sealing effect between the rings 15 of swelling body and the module rings 12-14 concurrently with the radial expansion of the rings 15 of swelling body. There are sealing rings 21 arranged between the module rings 12-14 and the additional pipe 9.
In Fig 1 there are also shown additional rings 22-24 surrounding the module rings 12,14, which are used for adapting the diametre of the device 1 to the actual pipe diametre. In this connection the additional rings 22 and 24 are fastened to the module rings 12,14, respectively by means of screws.
Due to the fact that the end collars 3 can be tightened in the direction towards each other by means of nuts 30,31, which nuts are in threaded engagement with the centre pipe 2, the rings 15 of swelling body will be clamped between the module rings 12-14, the desired clamping force being able to be chosen by varying the tightening of the nuts. In this connection should be observed that the additional pipe 9 has such a length that it does not impede the mentioned compression of the rings 15 of swelling body.
The centre pipe 2 is in its one end provided with a male part 32 of a docking mechanism and in its other end with a female part 33 of a docking mechanism. In this connection should be understood that by means of a so-called quick-coupling a conduit for compressed air (not shown) can be connected with the centre pipe 2 and pressurize this one, if desired.
The docking mechanisms also make docking to different supplementary tools possible.
A tube 34 is in connection with the centre pipe 2 and this tube is further connected with a pipe 35, which is closed in its free end 36. The pipe 35 is applied to the additional pipe 9 and has openings communicating with the openings 10 and 11 in the additional pipe.
The device according to the invention can also be provided with a nozzle 50 making possible to inject for instance filler via the device 1 in connection with the relining work. Due to the fact that the nozzle 50 is positioned in the middle region of the device 1, the filler outflow can be concentrated to an area limited by the gripping blocks 17. An elastic sleeve 51 is arranged to serve as a non-return valve in connection with the injection of filler. An inlet pipe for the filler 52 extends up to the nozzle 50.
From Fig 3 appears that the gripping blocks 17, preferably made of metal, are designed in that way that they together form a gripping ring, radially expand- able, the gripping blocks being located in their inner position when the centre pipe 2 is not pressurized. In Fig 2 the gripping blocks 17 are shown in an expanded position existing when the centre pipe 2 is pressurized. From Fig 2 appears that the gripping blocks move radially outwards to a contact against the inner surface of surrounding pipe, the surrounding pipe being indicated by broken lines and denoted by 100. As is apparent from Fig 2 there is a gap 61 between the gripping blocks 17 in the expanded position. When bringing the pressurizing of the centre pipe 2 to cease after requirements, the O-ring 18 will bring back the gripping blocks 17 to their inner position shown in Figs 1 and 3.
The gripping blocks 17 are suitably provided with barbs 62 for guaranteeing the best possible frictional engagement with the inner surface of the pipe 100. When pressurizing the centre pipe 2 also a
pressurizing of the tube 34 and the pipe 35 occurs. This in its turn has the consequence that the pressurizing also occurs of the space 63 existing between the additional pipe 9 and the inner jacket-surface of the ring 15 of swelling body, the last one 15 being forced to expand diametrically and due to that fact forces the gripping blocks 17 to move radially outwards to a pressing contact against the inner surface of the pipe 100, having the consequence that the device 1 is fixed in relation to the pipe 100. By reducing the medium pressure in the centre pipe 2 after that and accordingly in the space 63, the gripping blocks 17 by influence from the 0-ring 18 can return to its original inactive position in which there is no engagement with the pipe 100.
Fig 5 schematically shows an embodiment of the device according to the invention, the gripping blocks 17' being located in an inactive resting position, and Fig 6 shows the gripping blocks 17' in an expanded active position, the cavity 63' being pressurized. The cavities 64' (see Fig 5) limit the expansion possibility of the rings 15' of swelling body and the gripping blocks 17'.
Fig 7 shows a further embodiment of the device according to the invention in which relatively big additional rings 22"-24" are mounted onto the device at the same time as an exchange of gripping blocks 17' has been carried out so that the device can be used for another pipe dimension. Figs 8-10 show alternative gripping means 80-82 comprising a ring of an elastic material, for instance rubber, which gripping means are intended to be an alternative to the gripping blocks 17 primarily in those cases when there is no dependence upon maximum engagement ability in relation to the pipe 100. The gripping rings 80-82 can for instance be used when there is a desire to use the device in connection with
injection of filler. When using the gripping rings 80- 82 there is no need to use the O-ring 18.
It should be understood that the number of rings of gripping blocks 17 of the device of course can be varied from only one such ring of gripping means to several such rings depending upon which gripping qualities that are desired. For security reasons the number of O-rings 18 can be doubled so that a rupture of one O-ring will not put the device out of function. Furthermore, it should also be understood that the device according to the invention is very simple to rebuild in order to manage different pipe diametres by exchanging gripping blocks 17 and additional rings 22-24. There is also a possibility to place a tube (not shown) of for instance rubber in the space 63, the openings 10 and 11 communicating with corresponding openings in the tube.
The device according to the invention has a very large area of use since it can be docked with a lot of different fittings which are primarily used in connection with relining works.
The invention is not limited to what has been shown and described but changes and modifications of the invention are possible within the scope of the following claims.