WO1996005378A1

WO1996005378A1 - A method of lining a well or a pipe and a support ring for use when carrying out the method

Info

Publication number: WO1996005378A1
Application number: PCT/DK1995/000324
Authority: WO
Inventors: Kjeld Povl Nielsen
Original assignee: Kjeld Povl Nielsen
Priority date: 1994-08-09
Filing date: 1995-08-09
Publication date: 1996-02-22

Abstract

The process comprises the step of entering a number of still not joined elongated panels (1), which panels at their long sides include organs for joining said panels, inside the manhole (5). The panels (1) are thereafter joined to form a cylinder (11) which is properly placed inside the manhole (5) or the pipe. The annular space between the wall of the manhole (5) or the pipe and the cylinder (11) is then filled with a curable material (12) such as concrete. The invention further comprises a supporting ring to be used in the process.

Description

A METHOD OF LINING A WELL OR A PIPE AND A SUPPORT RING FOR USE WHEN CARRYING OUT THE METHOD

The present invention relates to a method for lining a well or a pipe, in which a lining comprising a number of panels with means at their side edges for mutual assembly in not assembled state is introduced into the well or the pipe, whereafter the panels are assembled to a self- supporting cylinder which is placed in the well or the pipe, following which the gap between the well or the wall of the pipe and the cylinder is filled with a hardenable material, like for instance concrete. Such a method is known from WO-A-911563 which describes a method, in which a lining is built up by a number of small, rigid, semi- circular ring elements which are stacked by pairs on top of each other to a desired height. By the term "selfsupport¬ ing" is to be understood that the cylinder assembled from panels keeps its cylindrical shape without collapsing under its own weight. When renovating for instance a leak well it is known to cast in a precast cylinder. Wells usually end, however, upwards in a cone with a manhole which is substantially smaller than the cross-section of the well itself. It is therefore necessary prior to introduction of the precast cylinder to remove said cone, which entails quite an amount of digging and nuisance for the traffic if the well (which is often the case) is positioned in a road.

From US-A-5 017 313 it is known to build up a concrete formwork from segment rings which are bolted together at their sides. The individual rings of segments may be lined at the outside with a plastic sheeting material which contrary to the concrete formwork remains in the well. This plastic lining is, however, at no time self- supporting. The object of the invention is to provide a method, by which a well or a pipe may be quickly and effectively provided with a lining. This object is met thereby that the panels used are flexible profile-panels with longitudinal ribs on one side face, said ribs extending in the assembled state of the cylinder in the longitudinal direction of the well or the pipe, and in that the assemblies run parallel to the ribs. The non-assembled panels may contrary to a complete cylinder be introduced through an opening, which is substantially smaller than the cross-section of the well or the pipe to be lined, for which reason it is not necessary for the access to be the size of a full cross-section.

In a preferred embodiment of the invention the panels are assembled prior to introduction into the well or the pipe to form a flat object which is rolled around a longitudinal axis to a diameter smaller than the diameter of the entrance of the well or the pipe. This possibility does not exist with the method according to WO-A-9115634 because the elements used there are rigid. By assembling the panels into a workpiece which only need to be assembled along two sides to form the cylinder it becomes relatively easy prior to the rolling together to cut at least one end of the workpiece in such a way that a cylinder made from the workpiece at one end is provided with for instance cutouts for pipe connections and the like and has a desired height. Spacers are preferably provided between the cylinder and the wall of the well or the pipe prior to the filling with hardenable material, and the cylinder is preferably supported in the interior by provision of foldable, extendable support rings along the interior face of the cylinder prior to the filling of the gap between the cylinder and the wall of the well or the pipe.

In addition to the described method the invention relates to a support ring for use when carrying out the method, which support ring comprises at least two curved, rigid bracket members which by means of joints are mutually connected to form an open ring, and which at their free ends comprise a means for pressing these two ends apart and fixing them relative to each other. Such a support ring may like the lining workpiece be introduced through an opening which is substantially smaller than the cross-section of the well or the pipe in order to be extended to abut the inner face of the cylinder and to support the latter and create an abutment against the pressure from the hardenable material. After the at least partial hardening of the hardenable material, the support ring may be made to collapse and can be removed without damaging the lining. The invention will be explained in detail in the following by means of embodiments with reference to the drawing, in which

Fig. 1 is a section through a well which has been provided with a lining, Fig. 2 the profile of a panel which is suitable for use in the method according to the invention,

Fig. 3 is a support ring for use in practising the invention, and

Figs. 4-8 is a device for keeping the two free ends of the support ring apart and for fixing them.

Fig. 2 shows the profile of a lining panel 1, which is suitable for use when carrying out the method according to the invention. The lining panel 1 shown^' is marketed under the name CON-PLAST and is made from PVC. The lining panel may have a thickness of for instance 2-2.5 mm. On one side the lining panel 1 is provided with Y-shaped ribs 2 which may protrude for instance 12-15 mm from the surface of the panel and which may be embedded in for instance concrete to bond the lining 1 thereto. At one of the sides the lining panel 1 is provided with a bead 3 which may be pressed into a corresponding slot 4 at the opposite side of an adjacent lining panel to assemble two lining panels. Thereby the faces of the lining panels opposite the ribs 2 will form a coherent smooth surface. Fig. 1 shows a well which consists of three well rings 5 and which ends in a cone 6 and a manhole 7. At the bottom the well ends in a banquette 8 with a groove 9 connected with a pipe 10. A cylinder 11 is inserted into the well, which cylinder consists of lining panels 1, the number of which depends on the diameter of the well and the width of the panels, which for instance may be 30 cm. This width has, however, no importance as such for the invention. Between the cylinder 11 and the well rings 5 concrete 12 has been cast, and in Fig. 1 support rings 13 are shown which support the cylinder 11 against the pressure from the concrete 12. The upper one of the support rings 13 is provided with hooks and is suspended in the upper edge of the cylinder 11. The remaining support rings 13 are suspended in the uppermost support ring by means of chains 14.

The support rings 13 may for instance be designed as shown in Figs. 3-8, where Fig. 3 shows the entire support ring 13, which consists of two rigid, curved bracket parts 15 which are mutually connected by means of a joint 16. This should make it possible to fold the two bracket parts towards each other and to prevent the two ends at the joint 16 in the shown position cannot be moved towards each other. It is, however, not a requirement that the two ends cannot be drawn apart.

The design of the ends of the bracket parts 15 opposite the joint 16 is shown from the side and from above, respectively, in Figs. 6 and 7. It will be seen that the ends 17 is cut obliquely and at the inside provided with fish plates 18 which protrudes over the ends 17.

Figs. 4 and 5 shows from the side and from above, respectively, a wedge 19 which is adapted to be inserted between the obliquely cut ends 17 to press them apart, thereby expanding the support ring 13. The wedge is provided with a threaded spigot 20 for fastening onto the fish plates 18 by means of a disc 21 and a nut 22.

Fig. 8 shows the ends 17 of the bracket parts 15 with the wedge 19 in position.

Prior to the situation in Fig. 1 the lining panels 1 were assembled to a plane, coherent workpiece. The profile of the banquette 8 along the wall of the well was recorded, and the workpiece made from the lining panels was cut correspondingly at one end and in such a way that a desired height was obtained. Then the workpiece was rolled into a roll with smaller diameter than that of the manhole 7. The roll was then lowered into the well and unrolled, following which the vertical sides of the workpiece were pressed together to form the cylinder 11. Spacers not shown are used for centring the cylinder 11 in the well. These spacers may easily be fastened to the Y-shaped ribs 2 of the lining panel, and they are for instance placed at the top and at the bottom of the cylinder 11. In case of deep wells spacers may also be placed at the centre of the cylinder 11. Very deep wells (for instance more than 3 m) are renovated by means of several cylinders which are placed on top of each other in a corresponding number of working steps, i.e. one cylinder is placed and then casting takes place, following which the next cylinder is placed on top thereof, when the concrete behind the first cylinder has hardened. Hereby an undesirable high hydraulic pressure at the lower end of the cylinder is avoided.

Collapsed support rings 13 were then taken down the manhole 7, positioned, unfolded and expanded to the position shown in Fig. 3, in which they abut the inner wall of the cylinder 11 to keep the cylinder 11 expanded during the subsequent pouring of concrete 12 in the gap between the well rings 5 and the cylinder 11. Vibration against the support rings 13 and the inner surface of the cylinder 11 is carried out. When the concrete 12 has at least partially hardened, the support rings 13 is removed, and the lining is finished.

As the method described requires no other access to the well than the one provided by the manhole 7, it is a comparatively quick and cheap operation to renovate a well by lining it as described above in comparison with the known techniques. It is thus possible by means of the method according to the invention to renovate a well in only two days. At the end of the day's work the cover is put in place, and there is no nuisance to for instance traffic outside the working hours.

Claims

C L A I M S

1. A method for lining a well (5) or a pipe, in which a lining comprising a number of panels (1) with means (3,4) at their side edges for mutual assembly in not assembled state is introduced into the well (5) or the pipe, whereafter the panels (1) are assembled to a self- supporting cylinder (11) which is placed in the well (5) or the pipe, following which the gap between the well (5) or the wall of the pipe and the cylinder (11) is filled with a hardenable material (12) , like for instance concrete, c h a r a c t e r i z e d in that the panels used are flexible profile-panels (1) with longitudinal ribs on one side face, said ribs extending in the assembled state of the cylinder in the longitudinal direction of the well or the pipe, and in that the joints run parallel to the ribs.

2. A method according to claim 1, c h a r a c t e r i z e d in that the panels (1) prior to introduction into the well (5) or the pipe are assembled to form a flat object which is rolled around a longitudinal axis to a diameter smaller than the diameter of the entrance (7) of the well (5) or the pipe.

3. A method according to claim 1 or 2 , c h a r a c t e r i z e d in that in view of the placing of the cylinder (11) spacers are provided between the cylinder (11) and the wall of the well (5) or the pipe.

4. A method according to claims 1-3, c h a r a c t e r i z e d in that the cylinder (11) is supported in the interior by provision of foldable, extendable support rings (13) along the interior of the cylinder (11) prior to the filling of the gap between the cylinder (11) and the wall of the well (5) or the pipe.

5. A support ring for use in carrying out the method according to claim 4, c h a r a c t e r i z e d in at least two curved, rigid bracket members (15) which by means of joints (16) are mutually connected to form an open ring, and which at their free ends (17) comprise a means (18-22) for pressing these two ends (17) apart and fixing them relative to each other.