IMPROVEMENTS RELATING TO THE LINING OF PIPELINES AND PASSAGEWAYS

Abstract: A method and means for lining pipe laterals (12) comprises making a thermoformed collar (18) from plastics sheet material, attaching an end of a lining tube (14) thereto, taking the tube (14) with its collar (18) into a main underground passageway (10) positioning the collar (18) in register with the lateral pipe and, jacking the collar (18) onto the main passageway surface (42-50) by a launcher apparatus, and everting the lining tube (14) through the collar (18) onto the lateral pipe surface inserting a preformed collar, to which a lining tube is attached, into the main end of the lateral and subsequently everting the lining tube into the lateral by fluid pressure.

Description: Improvements Relating to the Lining of Pipelines and Passageways This invention relates to the lining of pipelines and passageways, and in particular has reference to the lining of underground pipelines and passageways which are known as "laterals, which are pipelines and passageways which connect for example a main sewer pipe to a consumer point such as a domestic dwelling or other building. The invention relates to a lining for laterals, a method of lining laterals and a launcher apparatus for applying the lining to the lateral. Basically, in a sewerage system, a main sewer pipe will run underground directly along the line of a main street or thoroughf re, and the users of the system will be connected to the main sewer pipe by means of lateral pipes which extend transversely off the main sewer pipe to user points on opposite sides of the road, street or thoroughfare. The laterals tend to meet the sewer pipe at either of 2 angles namely 45 degrees or 90 degrees, although because of the antiquity of some of the sewer systems at least in countries like the United Kingdom, the lateral may meet the main sewer pipe at any angle, provided of course that the lateral can perform its function of discharging sewage and other effluent into the main sewer. There has been known now for a number of years a lining process for the lining of main sewer pipes wherein a flexible lining tube includes a resin absorbent layer which is impregnated with curable synthetic resin. The lining tube is urged by a fluid pressure onto the surface of the sewer and is held in position until the resin cures, whereby a hard rehabilitating lining forms on the sewer surface. The lining in effect is a pipe within a pipe and becomes freestanding when curing has been completed, which provides an extremely effective improvement of the sewer surface. More recently, there has been a demand for and a need to reline the lateral pipes using mainly a lining tube of the same basic construction as the lining tube which is used for the main sewer pipe, and a number of proposals for methods and apparatus have already been made in order to meet this requirement. We for example have effected a number of developments in this area, and details of these developments are disclosed in the following patent specifications British Patent Numbers: 2,091,611; 2,092,493, 2,096,265; British Patent Application Numbers: 8527700; 9127315.1; European Patent Number: 0241719; US Patent Numbers: 4,786,345; 4,677,472; 5,044,824; US Patent Application Numbers: 532,866; 07/419,068; International Patent Application Numbers: PCT/GB91/00364; PCT/GB91/00628. Because of the nature of the layout of main sewer pipe and laterals it is generally recognised that to insert a lining into a lateral, the best method is to evert the lining tube into the lateral by a "launcher" type apparatus which is positioned inside the main sewer. A main reason for proceeding in this way is that access to the lateral from the consumer point is inconvenient to the user, and frequently users will object strongly to working for effecting lateral lining, from a position inside the dwelling or building. It is obviously much better if the contractor can perform the lining operation from inside the main sewer as the consumer is therefore in no way disturbed other than to have the service cut off for a short period whilst the lateral lining takes place. In "launcher" apparatus, the apparatus is designed so as to have a pressure enclosure so that fluent medium under pressure can be applied to that enclosure, the enclosure has an outlet and is adapted so that the tube to be everted into the lateral extends from the outlet, and then a collar or flange thereof can be held in relation to the outlet so that by pressurising the enclosure the tube is everted into the lateral. The tube may be and preferably is enclosed in a carrier tube which simply forms a carrier for the lining tube and everts with the lining tube into the lateral. When the lining tube is in position, the carrier tube is removed so that it can be reused. A carrier tube is particularly important when the lining tube is one whih is impregnated with a curable resin, the carrier tube being in such arrangement a tube of a rubber like material such as neoprene, which is reinforced with fibrous scrim. One of the difficulties in effecting a lateral lining is to provide an effective sealing for the lining tube around the outlet of the lateral where it meets the main sewer. If the sealing is not effective, the lining tube can slip or it can ruck and folds may be left therein when it is finally placed in the lateral, and the present invention seeks to provide a means and method for overcoming this problem. In accordance with the invention in a first aspect there is provided a lining for lining of a lateral pipe branding off from an underground pipeline- or passageway, characterised in that a lining tube at one end is provided with a preformed sealing collar adapted to conform and seal to the inner face of the piping in the region where said lateral is connected to a mains pipe. In accordance with the present invention in a second aspect, a lateral lining method comprises using a preformed collar of a sheet material which under pressure will conform to the shape of the main sewer pipe and will effectively seal around the lateral connection to the main pipe, and wherein a said collar is attached to the underside of a flange or collar of the lining tube, and wherein a "launcher" holds the sealing collar and lining collar adjacent the lateral opening, and when the pressure chamber is pressurised, the lining tube is everted through the sealing collar and lining tube collar into the lateral. The "launcher" may be provided with a carrier tube in which the lining tube is contained. The lining tube may be of the type provided with a resin absorbent layer which is impregnated with curable resin, and the lining tube is held in position on the lateral surface until the curable resin is cured to form a rigid lining on said lateral surface. Preferably, in the preforming of the sealing collar, the collar is formed from a sheet of synthetic plastics material such as polyninyl chloride and the central edge of the collar has an upwardly turned rim which is for engagement inside the lateral, said rim lying on a cylindrical plane having its axis inclined relative to the remainder of a collar at the same angle at which the lateral is inclined relative to the main pipe. The upper edge of the said rim may be outwardly turned so as to provide a lip which serves as a means of gripping the lining collar when applied thereto. The lining collar may be adhered to the sealing collar by means of a suitable adhesive or other bonding material. The invention also provides a sealing collar for use in connection with the method as aforesaid. In yet a further aspect the invention provides a launcher apparatus for launching the lining as aforesaid, characterised by means for mounting the sealing collar by its edges thereon, jacking means for jacking the mounted sealing collar onto the main underground pipeline or passageway, around the lateral pipe, and a pressure chamber adapted to be supplied with fluid under pressure to evert the lining through the collar onto the lateral pipe surface. An embodiment of the present invention will now be described, by way of example, with reference to the accompanying drawings, wherein; Fig. 1 shows an underground pipeline or passageway and a lateral meeting same at an angle; Fig. 2 shows the same portion of the underground pipeline or passageway after the lateral has been lined in accordance with the method of the invention; Figs. 3 - 7 show in a sequence of steps the method and manufacture of the sealing collar shown in Fig. 2; Fig. 8 shows how the sealing collar and lining tube are brought together; Fig. 9 is a perspective view of a "launcher" apparatus which is used for inserting a lining tube in the lateral tube shown in Fig. 1; Fig . 10 is a sectional side view of the pipeline or passageway with the "launcher" in position therein to insert the lining tube in the lateral pipeline or passageway; and Fig. 11 is a perspective view of an alternative design of collar. Referring to the drawings, and firstly to Fig. 1, an underground pipeline or passageway (10) such as a main sewer is intersected by a side or lateral connection pipe (12) at an angle, typically 45 degrees. The apparatus and process to be described are for providing the lateral (12) with a lining tube to rehabilitate or repair same. The lining tube may be of any suitable construction, but typically will be a tube of fibrous felt material which is impregnated with a curable synthetic resin. Such impregnated tubes are now widely used for the lining of underground pipelines and passageways, and will not be described in further detail herein except to say that the tubes are held by fluid pressure against the surfaces to be lined, and are held in this condition until the resin cures when the pressure can be removed leaving the hard lining tube comprising cured resin with feld embedded therein, in position. Any suitable type of lining tube may be used however in the present invention. In the apparatus and method to be described, the lateral pipe (12) as shown in Fig. 2 is lined with a cured synthetic resin/felt lining tube (14) which at its lower end in Fig. 2 has a collar (16) which lies on the surface of the main pipeline or passageway (10). Additionally, there is a sealing collar (18) of plastics material which overlies the collar (16), and is provided with inner and outer bead formations (20) and (22) to provide an effective and neat sealing collar for the entire assembly. The sealing collar (18) is bonded to the lining collar (16), and provides a means whereby there will be smooth effluent flow from the lateral pipe into the main pipe. In order to perform the operation, certain apparatus is required, and the other figures of drawings illustrate what is involved. Referring firstly to Figs. 3 - 7, under factory conditions, a sheet (24) of synthetic plastics material such as p.v.c. is vacuum formed in suitable mould (26) having a main cavity (28) and a bead cavity (30) surrounding the main cavity. Sheet (24) is placed over the mould and suitably heated, and then the cavities (28) and (30) have vacuum applied thereto through for example pipes (32) and (34) so that the plastics material sheet is deformed as shown in Fig. 4 to take up the shape of the mould. The moulding thus formed is then severed through the central deformed portion to provide the collar (18) as shown in Fig. 5, and the collar (18) is provided with a central flange (36) which is configured at an angle by means of a hot forming tube (38) as illustrated in Fig. 6, the said angle being the same as the angle at which the lateral pipe (12) meets the main pipe (10). Finally, as shown in Fig. 7 heated shaper (40) is applied to the rim of the flange (36) to form the outwardly turned bead formation (22) as previously described in relation to Fig. 2, completing the manufacture of the sealing collar. With references made to Fig. 8, the sealing collar (18) is shown, after having been inverted from its Fig. 7 position, and the lining tube (14) with its collar (16) is inserted again under factory conditions, through the central aperture of the collar (18), until the collar (16) seats on collar (18). The collar (16) although of the same material as the lining tube (14) is not in fact impregnated with resin at this time, but it is bonded to the upper surface of collar (18) by a suitable adhesive or cement and again this fabrication takes place under factory conditions. In order to apply the lining to the lateral passageway (14) it is necessary to be loaded into a "launcher" equipment, which is illustrated in Fig. 9. The "launcher" comprises basically a tubular body (42) supporting a front arm (44) via a bracket (46), and a saddle bracket (48). Between the brackets (44) and (48) is a mounting cap (50) which is a tubular structure through which the lining and the carrier tube (to be described) pass in order to effect the eversion of the lining tube into the lateral pipe (14). The cap (50) is inter changeable with caps of different sizes depending upon the diameter of the lateral pipe to be lined, and it will be appreciated that the lining tube is tailored under factory conditions to be the correct size to line the lateral pipeline (14) . Fig. 10 shows the "launcher" when in position in the main pipe (10) and when in register with the lateral pipe (12) ready to evert the lining tube (14) into the lateral pipe (12), and referring to that figure, the body (42) is shown as being connected to a tail pipe (52) which is flexible, and serves as a containment means for pressurising gas e.g. compressed air, which is introduced into the interior of the body (42) by means of a compressed air line (54), in order to pressurise a chamber comprising the inside of the body (42) containment tube (52) and the cap (50). As shown in Fig. 10, a carrier tube (56) which is of flexible resilient material such as a rubberised fabric, has an end (58) folded over the outside of the cap (50), and the remainder of the carrier tube passes through the pressurising chamber. The main body of the lining tube (14) is carried inside the carrier tube, but the flanged end (16) projects therefrom and presses on the collar (18). The collar (18) is in turn supported on the arm (44) and bracket (48) so as to be presented to the lateral lining pipe (12) as shown in Fig. 10. When the "launcher" thus assembled is in position jacking feet or other suitable means on the "launcher" are operated, from ground level, to jack the "launcher" upwardly towards the lateral pipe (12) so that the sealing collar (18) is pressed against the surface of the main pipe (10), and deflects into curved configuration as shown in Fig. 10 and seals against this surface, the flange (36) of the sealing collar entering the mouth of the lateral pipe (12). When the "launcher" and the sealing collar are in this position, the interior of the "launcher" is pressurised via the compressed air pipe (54), and this causes the carrier tube and lining tube to evert into the lateral pipe (12) as shown in dotted lines in Fig. 10 and so the lining tube everts into and onto the surface of the lateral pipe (12) . When th lining tube includes a curable resin impregnated fibrous or felt layer, the lining is held in this position by the carrier tube until the resin cures, when the carrier tube is removed leaving the lining in position as shown in Fig. 2. Fig. 11 shows an alternative design for the collar 18. The collar of Fig. 11 is again thermofor ed from plastics material, but is generally rectangular in shape, but in being thermoformed is curved in the main body region 60 to the curvature of the pipe. At the ends of the body region 60 are formations 62 and 64 which are adapted to be engaged by the launcher (44 and 48). In the centre of the body portion 60 is provided the central aperture 64 through which the lining will be everted. It is also to be noted from Fig. 11 that around the thermoformed edge 66 are apertures 68, and similarly apertures 70 are provided in the upstanding flange 72 surrounding the aperture 64. These apertures 68 and 70 may be used for fixing devices in order to enhance the fixing of the lining collar to the thermoformed collar as shown in Fig. 11. The Fig. 11 collar differs from the Fig. 8 collar insofar as the body portion 60 is precurved to the curvature of the pipe whereas in the arrangement of Fig. 8 the body portion is flat and will be stressed to the curvature of the pipe as it is pressed thereto. The arrangement shown is for a lateral pipe which meets the main pipe at an angle for example in the order of 45 degrees. Obviously the system can be adapted for the lining of laterals which meet the pipeline at different angles, and for laterals which are of different sizes. A single "launcher" may be used for all sizes of lateral pipes which meet a main pipe at the same angle, and also "launchers" can be designed for other angles such as 60 degrees or even 90 degrees.

Claims: CLAIMS 1. A lining for lining of a lateral pipe (12) branching off from an underground pipeline- or passageway, characterised in that a lining tube (14) at one end is provided with a preformed sealing collar (18) adapted to conform and seal to the inner face of the pipe in the region where said lateral (12) is connected to a main pipe (10). 2. A lining according to claim 1, characterised in that said sealing collar (18) is thermoformed from a sheet of synthetic plastics material, such as polyvinyl chloride. 3. A lining according to claims 1 or 2, characterised in that the central edge of the collar (18) is in the form of an upturned rim (36) adapted for engagement inside the lateral (12), said rim (36) preferably forming a cylinder whose longitudinal axis is inclined in relation to the remainder of the collar (18) at the same angle at which the lateral (12) is inclined relative to the main pipe (10). 4. A lining according to any of claims 1-3, characterised in that the lining tube (14) is provided with a resin absorbent layer capable of being impregnated with a curable resin. 5. A lining according to any of claims 1-4, characterised in that a collar portion (16) of the lining tube (14) is adapted to be sandwiched between the piping and the sealing collar (18) in the applied state. 6. A lining according to any of claims 1-5, characterised in that the lining tube (14) is contained within a carrier tube (56). 7. A lining according to claim 5 or 6, characterised in that the rim (36) is outwardly turned so as to provide a lip (22) which serves as a means for gripping the lining collar (16) when applied thereto. 8. A lining according to any of claims 5-7, characterised in that the lining collar (16) is adhered to the sealing collar (18) by means of a suitable adhesive or other bonding material. 9. A method for lining a lateral pipe (12), branching off from a main underground pipeline- or passageway (10) by means of a lining tube (14) , characterised in the application of a preformed sealing collar (18), which is provided at one end of said lining tube (14) and which conforms and seals to the inside of the piping in the region where said lateral (12) is connected to the mains pipe (10), into the mains end of said lateral (12), and in the subsequent eversion of said lining tube (14) into said lateral (12) . 10. A method according to claim 4, characterised in that a launching device holds the sealing collar (18) adjacent the connection region. 11. A method according to claim 10, characterised in that the launching device is situated inside the mains pipe (10). 12. A method according to any of claims 9-11, characterised in that the lining tube (14) is everted by means of fluid pressure. 13. A method according to any of claims 9-12, characterised in that the lining tube (14) is impregnated by a curable resin and in that the lining tube (14) is held in position on the surface of the lateral (12) until the curable resin is cured, so as to form a rigid lining on said lateral surface. 14. A launcher apparatus for launching the lining as claimed in claim 1, characterised by means (44,48) for mounting the sealing collar (18) by its edges thereon, jacking means for jacking the mounted sealing collar (18) onto the main underground pipeline or passageway (10), around the lateral pipe (12), and a pressure chamber (42) adapted to be supplied with fluid under pressure to evert the lining (14) through the collar (18) onto the lateral pipe surface.

Inventors: WOOD ERIC, WOOD, ERIC
Applicants: INSITUFORM TECH LTD, WOOD ERIC, INSITUFORM TECHNOLOGIES LTD., WOOD, ERIC
Application year: 1993
Main classification: F16L55
IPC codes: F16L55