WO1988007154A1

WO1988007154A1 - Device in lining of pipes

Info

Publication number: WO1988007154A1
Application number: PCT/SE1988/000138
Authority: WO
Inventors: Kjell Persson
Original assignee: Kjell Persson
Priority date: 1987-03-20
Filing date: 1988-03-18
Publication date: 1988-09-22
Also published as: SE456848B; SE8701163L; SE8701163D0; AU1494088A

Abstract

The invention relates to a device (1) for inserting lining pipes (2) into an outer pipe (3). The device comprises means (30) for protecting the front end (10) of the lining pipe (2) and a sealing optionally arranged there against damage in connection with the very pipe insertion procedure. The protective means (30) are operable from an outer position to engage the lining pipe (2) at one (10) of its ends from the outside and/or to engage a sealing arranged externally on the lining pipe. Moreover, the protective means (30) are operable to an inner position to enable that the device (1) can be retracted through the central hole of the lining pipe (2). The device (1) also comprises gripping means (24) operable from an inner inactive position outwards to contact with the inner surface of the lining pipe (2). As the device can be retracted through the inserted lining pipes (2) the device (1) is useful also when e.g. stops occur in the pipe lining procedure, for instance at service lines connecting to the outer pipe (3).

Description

Device in Lining of Pipes This invention relates to a device for inserting lining pipes into outer pipes.

Lining of pipelines, so-called relining, is a quick and economical method of repairing for example leaking sewers or water-pipes disposed below ground.

An attractive relining method is using relatively short lining pipes of such a length that they can be put down e.g. in a well, interconnected and inserted e.g. into a leaking sewer to be repaired. The ends of the lining pipes are so embodied that said connection is made possible. Usually the lining pipes are of a plastic material but other materials are of course possible.

In connection with the very introduction of the lining pipes into the outer pipes certain problems arise. Among these can be mentioned that the front end of the lining pipe can be easily damaged as this end is unprotected and often subjected to knocks and scratching in connection with the introduction of the outer pipe mostly in a poor state. In case the front end of the lining pipe has an external packing intended to seal a gap between lining pipe and outer pipe there is a great risk that the packing will be so damaged in connection with the pipe being lined that its sealing function will not be as intended. It is the object of this invention to provide a device for introducing lining pipes into outer pipes which device eliminates the above-mentioned problems, and this object is achieved in that the device has been given the characteristic features defined in the claims. Illustrative examples of the invention will be described below in greater detail with reference to the enclosed drawings, wherein Fig. 1 shows schematically a lining of pipes going on between two wells, the inventive device being used, Fig. 2 shows a partly longitudinal section of the invention lining device, Fig. 3 shows parts of the device in a section on the line IV-IV according to Fig. 2, Fig. 4 shows parts of the device in a section taken along the line IV-IV according to Fig. 2, Fig. 5 is a simplified and partly cut front view of the inventive device and Fig. 6 shows schematically a finished pipe lining between two wells where a stop in the pipe lining is made at a connection of a service line.

As is apparent from Fig. 1 an inventive device 1 is used to introduce lining pipes 2 into outer pipes 3, said outer pipes in the example shown consisting of sewers extending between two wells 4 and 5. Pipe lining according to the method shown is for instance carried out when it is desired to repair a leaking pipeline. The pipe lining is carried out in such a way that a number of connectible lining pipes 2 are used, said pipes 2 being of such a length that they can be introduced into the pipeline 3 from the well 4.

Feeding of the pipe sections 2 into the pipeline 3 is made in such a way that a first lining pipe 2 is connected to the pipe lining device 1 which is inserted into the outer pipe 3 and located at the well 4. The lining device 1 is connected with a wire 6 and the lining device is drawn successively through the pipeline 3 towards the well 5 in that the wire 6 is rolled onto a drum 7. In the example shown the pipe sections 2 are interconnected by means of a special tool 8 so that they form a coherent group of lining pipes. The interconnection of the pipes 2 can for instance be performed thanks to the fact that the pipes have means that engage each other by snap-in closure. Thus, as mentioned above the interconnected lining pipes

2 are introduced into the outer pipe 3 by the aid of the inventive device 1 in such a way that the wire 6 connected to this is successively rolled onto the drum 7. It is important that the lining device 1 protects the free end 10 of the first pipe 2 so that this end is not damaged. This is especially important as normally a sealing 11 placed on the outside of the pipe 2 is also adapted at this pipe end 10, said sealing 11 being intended to seal between the pipe 2 and the pipe 3 so that the liquid will really run en m the lining pipes 2 after completed pipe lining. It is also very important the device 1 , simultaneously as it protects the pipe end 10, has not so great an outside diameter that it restricts unnecessarily the use of a maximum diameter of the pipes 2. The device 1 will now be described more in detail with reference to Figs. 2-5. The device 1 is built around a frame 20 and has at its front end a tow eyelet 21 and at its rear end a tow eyelet 22. The tow eyelets 21 and 22 are arranged in order that it should be possible to draw the pipe lining device 1 by the aid of wires forwards and backwards in the oute pipe 3. Furthermore, the device 1 exhibits a gripping unit 23 comprising for gripping means 24 which are outwardly operable from an interior inactive position to a pressing contact with the inner surface of the lining pipe 2 so that said pipe 2 is retained at the device 1 and accompanies this when drawn in the outer pipe 3. The gripping means 24 are preferably externally provided with barbs 25 or other projecting portions to ensure that a satisfactory engagement is obtained with the inner surface of the pipe 2. The gripping means 24 are moved between an outer active position and an inner inactive position by the influence of a pressure medium cylinder in the form of for example a single-acting air cylinder 26 with spring return, the piston rod 27 of which actuates slewing brackets 28 of a link mechanism 29 at a movement from the cylinder so that the gripping means 24 move outwards to engagement with the inner surface of the pipe 2. When the pressure in the air cylinder 26 is reduced the piston rod 27 returns into the cylinder 26 with the result that the gripping means 24 move a distance inwards towards the centre to their inactive positions and no longer are in engagement with the inner surface of the pipe 2.

In order to clarify the location of the pipe 2 in relation to the pipe lining device 1 a pipe 2 has been indicated by means of dash-dot lines in Figs. 2, 3 and 5. It is apparent from this that the front end 10 of the pipe 2 is protected by four protective means 30 which engage the front end section it of the pipe 2 from the outside and protect this as well as a sealing, if any (not shown), arranged externally en the pipe end which can possibly be compressed, if desired, by means of the protective means 30 to an inactive introducing position. The protective means 30 are provided with a bent plate 31, the form of which is adapted to the outside diameter of the pipe 2, and the protective means 30 also comprise a stop lug 32 to abut the front end 10 of the pipe 2. The protective means 30 are supported by arms 33 which are articulatedly arranged about fulcrums 34, resulting in that the protective means 30 are movable between an outer and an inner position which will be described below in greater detail.

The lining device 1 has at its front end a pressure medium cylinder 40 for example in the form of a single-acting air-cylinder with spring return, the piston rod 41 of which supports a hub 42, by means of which four wires 43 are connected, said wires 43 running to the arms 33 and being connected with these, as is apparent from Fig. 2. The wires 43 run over guide rollers 44. When the air cylinder 40 is not pressurized the piston rod 41 is in an inner position at which the wires 43 allow the protective means 30 to be in an outer position at which the end 10 of the pipe 2 can be inserted below the protective means 30 and be removed from there, respectively. When the air cylinder 40 is activated by means of compressed air the piston rod 41 moves in an outward direction from the cylinder, i.e. to the left in Fig. 2, resulting in that the wires 43 pull the protective means 30 in an inward direction towards the longitudinal central shaft of the device 1. This means that when a pipe 2 is on the device 1 the protective means 30 are pressed against the outer surface of the pipe and possibly that of the seal, and when there is no pipe 2 on the device 1 the protective means 30 are still drawn a distance inwards to an inner position where the protective means 30 are so much brought together towards each other that they can pass freely through the central hole in a pipe 2, enabling that the whole lining device can be returned, if desired, for example through a group of lining pipes 2 moved by it to a desired final position in the outer pipe 3. Above all this is necessery when a step is made in a pipe lining in connection with service lines 70 connecting to the outer pipe 3 and the like, as is exemplified in Fig. E.

The lining device 1 also comprises a number of wheels or runners so located that the back transport of the device 1 through the pipes 2 can be made without undesired wear between the device 1 and the pipe walls. If needed, the wheels or the runners can be made resilient and operable in outward direction. In the embodiment shown four wheels 50 are arranged in the front part of the device 1 and four wheels 51 in the rear part thereof.

The function and use of the device 1 will be explained more closely in the following. The device 1 is placed in the outer pipe 3 to be lined so that it is accessible from a well 4, a lining pipe 2 being brought over the gripping unit 23, the gripping means 24 of which are located in an inner position at this stage, and the pipe 2 is brought over the device 1 until its end 10 gets in contact with the stop lugs 32 of the protective means 30, said protective means 30 being located in their outermost position at this stage. Then the cylinders 26 and 40 are not pressurized. When the pipe 2 is positioned, the cylinders 26 and 40 are pressurized, the gripping means 24 moving outwards to engagement with the inner surface of the pipe 2 and the protective means 30 moving inwards to contact with the outer surface of the pipe 2 and a possible sealing arranged thereon, resulting in that the pipe 2 is fixed to the device 1, as indicated in Fig. 1. The next step will be to draw the device 1 and the pipe 2 in the pipe 3 successively by means of the wire 6 simultaneously as possible further lining pipes 2 are gradually connected which is done in the well 4. When the interconnected lining pipes 2 have ob tained a desired length and drawn into the outer pipe 3 to a desired final position the pressure in the cylinder 26 is released, the gripping unit 23 being inactive through the inward movement of the gripping means 24 some distance, the engagement with the inner surface of the pipe 2 thus ceasing. The pressure in the cylinder 40 is also released with the result that the protective means 30 leave their hold of the outer surface of the pipe 2. The next step will be to draw the device 1 by means or the wire 6 further a bit in forward direction so that the protective means 30 quits leave the cuter surface of the pipe 2, after which the protective means 30 by pressurizing the cylinder 40 can be manoeuvred to their innermost position enabling that the device 1 can pass the central hole of the pipe 2. There is now a possibility to draw the device 1 back towards the well 4 by means of a wire (not shown) connected to the rear tow eyelet 22. It will be appreciated that said retraction is quite necessary in many cases as several different groups of interconnected lining pipes are sometimes introduced between two wells and stops in the pipe lining are made in zones where for example service lines connect to the outer pipe 3 (see for instance Fig. 6).

Thus, it will be appreciated that the device of the invention is extremely useful as when drawing in a lining pipe 2 it protects the front end 10 of the first pipe 2 in an interconnected pipe group and also protects a sealing arranged externally on the pipe 2 simultaneously as the device can be retracted through the lining pipes which it has drawn in. This is extraordinarily important.

Thus, said retraction of the device 1 through the lining pipes 2 enables that stops in the pipe lining, for instance at service lines connecting to the outer pipe 3, can be made. Thanks to this, in turn, ground excavations on these places can be eliminated.

For reasons of simplification certain connection lines for for example compressed air have been omitted in the figures.

The inventive drawing device 1 can be simply adapted to different pipe dimensions by adjustment and exchange of details depending on diameter. For example, the gripping means 24 can be simply replaced or supplemented. The protective means 30 can also be simply replaced but it should be mentioned here that there is also a possibility to change the position of the protective means 30 by an adjustment of the length of the wires 43.

It will also be appreciated that for example the cylinders 26 and 40 need not necessarily be compressed-air operated but hydraulic oil cylinders can of course also be used. Thus, the invention is net restricted to what has been shown and described but amendments and modifications thereof are possible within the scope of the appended claims.

Claims

Claims 1. A device for inserting lining pipes (2) into outer pipes (3), c h a r a c t e r i z e d in that the device (1) comprises protective means (30) operable from an outer position to engage the lining pipe (2) at one (10) of its en from the outside and/or to engage a sealing arranged on the lining pipe and that the protective means (30), moreover, are operable to an inner position to enable that the device (1) can pass the central hole of the lining pipe (2).

2. The device of claim 1, c h a r a c t e r i z e d in that the protective means (30) are pivotable around fulcrums (34) by way of arms (33).

3. The device of claim 2, c h a r a c t e r i z e d in that the operating movement of the protective means (30) is accomplished by means of a pressure medium cylinder (40), the piston rod (41) of which is connected by way of wires (43) with the arms (33) of the protective means and that the wires (43) run over guide rolls (44).

4. The device of any one of claims 1-3, c h a r a c t e r i z e d in that the protective means (30) comprise a bent plate (31), the curvature of which is adapted to the outer contour of the lining pipe (2) and/or to an outer contour of a sealing arranged on the sealing pipe.

5. The device of any one of claims 1-4, c h a r a c t e r i z e d in that the protective means (30) comprise a stop shoulder (32) to determine axially the position of a lining pipe (2) applied to the device (1).