WO1992014961A1

WO1992014961A1 - A method and a device for feeding a flexible lining material

Info

Publication number: WO1992014961A1
Application number: PCT/SE1991/000777
Authority: WO
Inventors: Thomas Lundmark
Original assignee: Inpipe Sweden Ab
Priority date: 1991-02-22
Filing date: 1991-11-15
Publication date: 1992-09-03
Also published as: JPH06500276A; SE9100524D0; AU9121291A; JP2533724B2

Abstract

A method of lining a passage, which is entirely or partially surrounded by walls, by everting a hoseformed, curable laminate into the passage under utilization of a pressure medium acting inside the laminate against its end surface for feeding the same into the passage and radially outwards against the inside of the everted laminate for pressing the everted laminate to contact with the wall of the passage which entirely or partially surrounds the passage. In order to avoid an uncontrolled varying eversion velocity or force, each part of the laminate (50), which is in turn to be fed into the passage (51), is unloaded before the feeding is begun by a stepwise feeding of the laminate (50) to a pressurised position in direct connection to the entrance (52) of the passage. When the laminate (50) with its final end has reached up to the mentioned pressurised position, a braking force of such adapted strength is connected in so that the eversion pressure and by that the eversion velocity are maintained essentially unchanged until the laminate (50) is entirely everted.

Description

A METHOD AND A DEVICE FOR FEEDING A FLEXIBLE LINING MATERIAL

This invention relates to lining of a passage which is entirely or partially surrounded by walls, or hollow, preferably elongated objects like for instance water conduits or sewer conduits being in the ground, other types of pipelines in the ground as well as on the ground, flue channels and ventilation ducts and other channels and passages, with a preferably hose- shaped laminate containing a curable plastic material, which laminate is introduced into the object that shall be lined and is thereafter made for stable by causing the plastic material in the laminate to be cured. More closely this invention relates to a method and an apparatus for introduction of such a hose-shaped, curable laminate into a hollow, preferably elongated object in the form of a pipeline, a channel, a passage or the like. For internal lining of different types of pipelines and channels and other passages, hose-shaped, curable laminates are used which by means of a pressure medium are normally introduced by being everted into the pipeline, the channel or the passage that shall be lined and which after or during the eversion itself are caused to be cured for achieving a formstable lining.

When introducing hose-shaped, curable laminates intended for lining by everting the same into a pipeline, channel or the like by using a compressed pressure medium like for instance air, steam or another compressible gas, there is at least the essen- tial demand that the introduction of the laminate shall be able to be made with a controlled velocity and under such circumstan¬ ces that the available force at least is capable of pressing out the hose-shaped, curable laminate to contact against the pipe wall that shall be lined and keep the laminate pressed against the pipe wall during the entire eversion process. However, with known eversion methods and equipments it has appeared that the available eversion force varies essentially during eversion of one and the same laminate and has the consequence, in those caseε when it is too small, that the laminate is not caused to come into contact against the wall that shall be lined and brings about in those cases when it is too strong, which often occurs in unfavourable introduction circumstances, an unwished redistribu¬ tion or removal of the curable plastic material inside the laminat . In the market there is also such an equipment for introduc¬ tion of hose-shaped, curable laminates into a pipeline by ever¬ sion, which comprises a pressure-tight covering which has to be dimensioned in that way that partly it encloses the hose-shaped laminate, prepared for eversion, entirely, i.e. a length corre¬ sponding to maximum lining length, and being rolled up on an unwinding roller together with a perforated heating hose con¬ nected to the final end of the laminate for supply of necessary heat in the form of steam for cure of the plastic material, partly can internally be set under pressure with the pressure which is maximally necessary for the eversion of the hose-shaped laminate in accordance with valid requirements and which after the eversion also has to be able to be maintained internally in the everted laminate for its forced contact against the wall that shall be lined during the time which is necessary for the cure of the curable plastic material in the laminate. The mentioned covering with the unwinding device for the hose-shaped laminate, stored on a roller, is normally placed on the ground surface and is connected to the pipeline, which is in the ground and which shall be repaired, by means of an essentially S-shaped, pressure tight connection pipe through which the hose-shaped laminate is accordingly fed forwardly and via which the necessary pressure medium is supplied to the hose-shaped laminate for its eversion into the pipe line. During its passage through the connection piP^e the hose-shaped laminate as well as the following heating hose will be drawn towards and by the two right-angled bends of the connection pipe, which gives rise to varying frictional forces counteracting the feeding forwards of the hose-formed laminate bringing about large difficulties to achieve a con- trolled eversion velocity and eversion force.

The purpose with this invention is therefore to solve the above mentioned problem in that way that lining of a passage, which is entirely or partially surrounded by walls with a curable laminate which is everted into the passage, can be carried out under entirely controlled conditions regarding force as well as velocity and that this can be realized with an equipment having essentially lower weight and being essentially less space requiring than known eversion equipments and which besides that makes the eversion of essentially larger lengthes possible tha what has been possible up to now. Thus, with controlled condi¬ tions is achieved that the eversion force brought about by th pressure medium and by that the eversion velocity entirely or partially dependent upon the mentioned force can be neither too small or too strong but can always be maintained on a suitable level during the whole eversion procedure.

This purpose is achieved by the fact that the method and the apparatus according to the present invention have the characterizing features mentioned in the following claims.

In the following the invention is described more closely with reference to the accompanying drawings, in which Fiσ. 1 shows a view of a feeder according to the invention, Fig. 2 shows a section along the line II-II of Fig. 1 , Fiσ. 3 shows a section along the line III-III of Fig. 2, Fiσ. 4 shows a section mainly along the line IV-IV of Fig. 1, Fiσ. 5 shows a view seen mainly along the line V-V of Fig. 1, Fig. 6 shows a block diagram over valves being part of the feeder, Figs. 7 to 10 illustrate sche¬ matically the different steps of the process during introduction of a laminate into a pipeline by eversion according to method of the invention.

With reference to the Fig. 1-6 a feeder 10 according to this invention shall be more closely described, which feeder is specially intended for feeding a hose-shaped laminate 50 by eversion into a pipeline, a channel or a passage that shall be lined.

The feeder 10 comprises two cylindrical closing sections 11 and 12, a storing section 13 positioned between these two sec¬ tions 11 and 12, a raising ring 14 provided with flanges and arranged on top of the upper closing section 11 and a feeding out section 15.

Each of the two closing sections 11 and 12 comprises a cylindrical membrane 16, provided with flanges at the ends, see also Fig. 7, made for instance of rubber, the membrane 16 of the upper closing section 11 with its upper flange 17 being fastened between the flange 18 of the raising ring and the upper flange 19 of the closing section and with its lower flange 17 between the lower flange 19 of the closing section and an internal flange or a flange 20 turned inwards of the storing section 13 by means of a bolt joint or bolts 21. In a similar way the membrane 16 of the lower closing section with its upper flange 17 is fastened be¬ tween an external flange 22 at the lower part of the storing section and the upper flange 19 of the closing section and with its lower flange 17 between the lower flange 19 of the closing section and the upper flange 70 of the outfeeding section 15 by means of a bolt joint or bolts 21.

Each membrane 16 of the closing section can be individually influenced to a closing position, in which the membrane 16 has been forced to enclose a hose-shaped laminate 50 introduced into the feeder 10 from above for locking the same. This enclosure of the membrane 16 around the laminate is made by means of a gaseous pressure medium or a pressure medium in liquid state which via an inlet 23 is introduced into respective closing section 11, 12 between the membrane 16 and the inner surface 24 of the section, for instance under such pressure that the membrane 16 can be forced to close itself entirely if that should be necessary.

Due to its internal flange 20 the storing section 13 of the feeder is given a larger diameter than the closing sections 11,

12 and has this diameter along the major part of its height but at its lower part narrows in a hopper-like way to the same diameter as the closing sections 11, 12. Furthermore, at its upper part the storing section 13 is provided with a sleeve- formed attachments 25 for telescopic legs 26 in a suitable number, for instance three, as is shown in the drawings so that the feeder can be erected in an essentially vertical position independently how the ground looks like. Each such telescopic leg

26 is shown to comprise three parts, i.e. an outer part 27 which articulately carries a foot plate 28, an intermediate part 29 and an inner part 30 detachably fastened in the intended attachment

25, these parts 27, 29, 30 being adjustable in relation to each other and lockable in each adjusted position by means of locking screws 31 which are suitably provided or designed with handles 32. The number of telescopic legs can of course be another one than what has been shown in the drawings and has been mentioned above and this has also relevance to the number of parts in the telescopic legs which can also be made pneumatically or hydrauli- cally adjustable and lockable instead of being manually operated. In the outfeeding section 15 of the feeder is introduced partly a pressure medium either in the form of a gas, preferably air or a liquid, preferably water, via an inlet 33, which pressure medium is used for introduction of the hose-formed laminate 50 in the pipe that shall be lined by eversion, partly a lubricant via an inlet 34 for reduction of the friction that may arise after the outfeeding section 15 during the introduction of the laminate into the pipe that shall be lined. With 35 is in Fig. 3 denoted a connection socket for connection of a manometer 80 (Fig. 9) or the like which registrates and shows the pressure that prevails inside the outfeeding section 15.

The outfeeding section 15 which in the embodiment shown in the drawings has a conically decreasing design from its attaching flange 36 to a cylindrical end part 37 is internally provided with a cylindrical shield 38 connected with the flange 36, as specially appears from Fig. 3, through which shield the lining laminate 50 passes during its feeding through the feeder and into the pipe 51 that shall be lined. This shield 38 which is only shown in Figs. 2, 3 and 7 has such an extension in the direction downwards that it passes the pressure medium inlet 33 as well as the lubricant inlet 34 and shields by that the laminate passing through the shield 38 from the pressure medium and the lubricant spurted in through the inlets 33, 34 under pressure. Thus, the shield 38 deflects the incoming pressure medium and the lubricant rays downwards and with one leading edge 39 preferably going round the edge and being designed folded outwards at its end leads the pressure medium as well as the lubricant outwards to¬ wards the inside of the wall of the section and accordingly not in towards the laminate passing through the shield 38 and the outfeeding section.

The lubricant which consists of a suitable oil is stored in a reservoir 40 arranged at the outside of the lower closing section 12 and is spurted into the outfeeding section 15 through the inlet 34 by means of an ejector 41 which is connected to a sucking pipe 43 existing in the reservoir 40 through a conduit 42 in the form of a pipe or a hose, and which is driven by means of compressed air which is supplied to the ejector 41 via a conduit 44. With a conduit 45 in the form of a pipe or a hose the ejector 41 is connected to the lubricant inlet 34 in the outfeeding section 15 of the feeder and on the outlet side of the ejector there is further arranged a spring-loaded non-return valve 46 which is not opened until a predetermined pressure has been achieved. Thus, not until the opening pressure of the non-return valve has been overcome, the ejector 41 is capable of spurting lubricant into the outfeeding section 15 of the feeder. For regulation of the amount of the lubricant which has to be intro- duced per time unit, there is arranged a regulation valve 47 on the sucking side of the ejector.

The cylindrical part 37 of the outfeeding section is pro¬ vided with a loose attachement flange 47 on its outside which flange is kept in place by a ring 48 arranged at the cylindrical part, which ring constitutes a seat for a gasket 49 with its side which is turned away from the loose attachement flange 47.

When using the feeder according to the invention for intro¬ duction of a hose-shaped, curable laminate 50 into a pipeline 51 that shall be lined, the essentially vertically erected out- feeding section 15 of the feeder 10 is connected (Fig. 7) to the entrance end 52 of the pipeline 51 by means of a connection pipe 53 with an end portion 54 bent to 90°. The connection pipe 53 is connected to the outfeeding section 15 of the feeder by means of its attachement flange 47 in such a way that the connection pipe 53 with its end portion 54 debouches into the end 52 of the mentioned pipeline 51, as is schematically shown in Fig. 7. Hose- shaped laminate 50 can now be introduced into the feeder 10 from above from a storage, not more closely shown in the drawings, which storage can be a container or the like to such a length that the end 55 of the laminate can be folded out and back around the end portion of the connection pipe and be connected with this one essentially air tight, for instance by means of a hose clamp 56 or the like.

By doing that it is ready to start the feeding of the laminate 50 into the pipeline 51 by eversion, which is made (Fig.

6) by means of two manual valves 57 of 3/2-way type arranged in series in a control pressure conduit 58 which is connectable to a control pressure source by a quick coupling 59. The pressure medium to the membrane 16 of the closing sections is received from a pressure medium source not more closely shown which is connectable to the pressure medium conduit 60 of the feeder via a security coupling 61, which conduit 60 is connected with the inlet 23 of the closing sections. In the pressure medium conduit 60 to respective closing section 11, 12 is further arranged a control pressure controlled main valve 62 of 5/2-way type, which valves 62 controlled by the pilot valves 57 bring about alternate connecting and disconnecting of the membranes 16 of the two clos- ing sections. In the pressure medium conduit 60 between a closing section and a main valve 62 belonging to it there is arranged a rapid unloading valve 63 for a rapid evacuation of pressure medium acting on the membrane on the section. In the control pressure conduit 58 to the main valves 62 there is also arranged a throttle valve 64 with a by-pass-connected non-return valve 65 allowing the control pressure flow to its main valve 62 but not in the opposite direction, whereby the return flow from the membrane 16 of respective closing section has to pass through the throttle valve 64 and by that is achieved an adjustable delay of the return to the original position of respective main valve.

All mentioned valves are arranged in an operation board 66 fastened to the upper closing section 11 of the feeder, which board is easily reachable from a platform 68 fastened to the lower closing section 12 of the feeder and provided with verti- cally adjustable legs 67.

When pressing in the operation means 71 of the pilot valves 57 manually, the two main valves 62 are exposed to intended control pressure and are adjusted so that the valve 62 of the closing section 12 is opened for pressure medium to the membrane 16 of the mentioned section whereas the valve 62 of the second closing section is kept closed. By that the membrane 16 of the lower closing section 12 of the feeder is forced to enclose and lock the laminate 50 in the mentioned lower closing section 12. Thereafter in one or another manual or mechanical way further laminate 50 is introduced into the feeder 10 from above from the mentioned storage until the storing section 13 of the feeder is filled up.

In this position the membrane 16 of the upper closing unit 11 of the feeder is forced to enclose the laminate 50 for locking this one to the closing unit 11 (Fig. 9) and when that has happened the pressure medium from the lower closing section 12 of the feeder is evacuated so that its membrane 16 is opened entire- ly and allows the laminate stored in the storage 13 to pass through the lower closing unit 12, the outfeeding section 15 and down into the connection pipe 53. Thereafter the pressure medium is connected in which is intended for the eversion and which comes in through the inlet 33 to the outfeeding section 15 and is deflected in the direction downwards by the shield 38 and down between the inside 72 of the connection pipe and the laminate 50. This pressure medium further acts on the end surface 73 (Fig. 9) of the laminate formed by the folding back and will therefore draw laminate into the pipeline 50 at the same time as it is everted, and everted laminate will at the same time by the pressure medium be pressed out to contact against the inside of the pipeline 51 being under lining, as is schematically apparent from Fig. 9.

When laminate 50 fed up has been everted into the pipeline the membrane 16 of the lower closing unit 12 by influence of the pilot valves 57 is again forced to enclose the laminate in the lower closing section 12 at the same time as the membrane 16 in the upper closing section 11 is forced to open, whereby further laminate is introduced until the storage 13 of the feeder is again filled up. Thereafter the membrane 16 of the upper closing section is closed for locking the laminate in the upper closing section 11 at the same time as the membrane 16 of the lower closing section is again opened in order to allow the laminate being in the storing section 13 of the feeder to pass through the closing section 12, feeding section 15 and down into the connec¬ tion pipe 53 and its bend 54.

Thus, laminate which is drawn into the pipe line 51 is loose or unloaded and therefore offer a very little of resistan¬ ce, whereby the force which is necessary for the eversion can be kept small and to that also contributes that fact that the con¬ tact surface of the laminate or the enclosing angle towards the inside of the pipe bend is also reduced essentially thanks to the fact that the laminate 50 which is drawn into the pipeline is not kept stretched out but lies so to say loosely and has a posibili- ty to sink down gradually into the pipe bend 54 with a smaller enclosing angle as a result of that and by that also the fric- tional forces counteracting the insertion of the laminate are reduced.

Thus, in the way mentioned above the closing sections 11, 12 of the feeder of the invention are forced to operate alterna¬ tely for stepwise feeding of laminate forwards and this is going on until the final end of the laminate is in the vicinity of the upper end of the feeder, a braking cable 75 being fastened to the mentioned end and a cover 76 being locked to the raising ring 14 of the feeder. The mentioned cover 76 is on its top side provided with a breaking wheel 77 and possibly also a braking wheel 78 (Fig. 1) for the braking cable 75 by means of which the force which is necessary for the eversion of the rest of the laminate 50 is regulated to essentially the same level as during the ever¬ sion of the first half of the laminate.

This invention is not limited to what has been described above and to what has been shown in the drawings but can be changed and modified in many different ways within the scope of the invention idea defined in the following claims. Thus, the storing section 13 of the feeder for instance may comprise a bellow device which makes a relative movement possible between the two closing stations 11 and 12, there being arranged a linear motor between these sections, for instance hydraulic cylinders, for displacing the closing section 11 in relation to the closing section 12, whereby a mechanical feeding of laminate from the storage to the storing part is achieved.

Claims

Claims 1. A method of lining a passage, which is entirely or partially surrounded by walls, by everting a hose-shaped, curable laminate into the passage under utilization of a pressure medium acting inside the laminate against its end surface for feeding the same into the passage and radially outwards against the in¬ side of the everted laminate for pressing the everted laminate to contact with the wall which entirely and partially surround the passage, c h a r a c t e r i z e d in that each part of the laminate (50) which is in turn to be fed into the passage (51) is unloaded before the feeding is made into the mentioned passage by a stepwise feeding of the laminate (50) to a pressurized position in direct connection to the entrance (52) of the passage, and that when the laminate (50) with its final end has reached up to the mentioned pressurized position, a braking force of such adapted strength is connected that the eversion pressure and by that the eversion velocity are maintained essentially unchanged until the laminate (50) is entirely everted.

2. A method according to claim 1, c h a r a c t e r - i z e d in that the braking force is transmitted to the laminate (50) by a braking cable (75) which is connected with the final end of the laminate.

3. A method according to claim 1 or 2, c h a r a c t e r¬ i z e d in that the laminate (50) is fed forward stepwise to the pressurized position by being alternately held stationarily in at least two separated closing positions (11, 12) , which are ar¬ ranged one after the other in the feeding direction of the laminate, by in these positions existing pressure controlled membranes (16) .

4. A method according to claim 3, c h a r a c t e r ¬ i z e d in that when the second membrane (16) in the feeding direction is opened, laminate is fed forwards from a storing section (13) , arranged between the two closing positions (li, 12) , provided with membranes, to the mentioned pressurized position.

5. A method according to claim 3 or 4, c h a r a c t e r¬ i z e d in that when the first membrane (16) in the feeding direction is opened and when the second membrane (16) in the feeding direction encloses the laminate and holds this one stationarily, laminate (50) is fed to the storing section (13) between the two closing positions (11, 12) provided with membranes (13) .

6. A method according to any one of the claims 3-5, c h a r a c t e r i z e d in that the laminate (50) is fed from a storage to the storing section (13) being between the two closing positions (11, 12) provided with membranes.

7. A method according to claim 6, c h a r a c t e r - i z e d in that one of the two closing positions, provided with membranes, is displaced forwards and backwards in relation to the other closing position a certain distance for feeding laminate from the storage to the storing section (13) .

8. A method according to any one of the claims 3-5, c h a r a c t e r i z e d in that the braking cable (75) , which extends through the two closing positions (11, 12) , provided with membranes, is given intended braking force by the one and/or the other of the pressure controlled membranes (16) of the closing positions and/or by an adjustable, brakable braking wheel (78) .

9. Apparatus for lining a passage which is entirely or partially surrounded by walls by everting a hose-shaped, curable laminate into the passage under utilization of a pressure medium acting inside the laminate against its end surface for feeding the same into and through the passage and radially outwards against the inside of the everted laminate for pressing the everted laminate to contact with the wall, which entirely or partially surrounds the passage, c h a r a c t e r i z e d in that a step feeder comprising at least two closing positions (11, 12) , provided with membranes is connected to an entrance to that passage that shall be lined by a tubular connection means for stepwise feeding of laminate (50) to this connection means which together with an outfeeding part of the step feeder is pressuri¬ zed by the eversion pressure during the eversion of the laminate.

10. An apparatus according to claim 9, c h a r a c t e r- i z e d in that the membranes (16) of the closing positions are pressure controlled for alternate locking and release of the laminate (50) extending through the feeder.