EXCAVATION

The present invention relates to a system for excavation-free sanitation services of tapping sleeves used for connection of one or more branch pipes to a main water pipe. The system uses a pipe robot in a main water pipe which is equipped with different tools to remove possible sediments, process contact faces in connection to sanitation services and seal/reconnect one or more tapping sleeves of branch pipes.

The present invention also relates to a method for excavation-free sanitation services of tapping sleeves used for connection of one or more branch pipes to a main water pipe.

The pipe robot is preferably a standard pipe robot which is commercially available.

Backgroundd of the invention

Leakage in drinking water systems is a widespread problem with large direct and indirect costs. In addition to direct costs related to pipes and fittings, the indirect cost of construction works in urban streets are very high. Large cost savings can be achieved by the use of excavation free solutions. There are developed refined methods for sanitation services of the main water pipes, for example by using a glass fibers fiberglass casing stretched with polyester. To actuate the full potential of such solutions, it is necessary to have a system for excavation-free sanitation services of the tapping sleeves connected to the branch pipes. Based on experience, the cross-section of the tapping sleeves may be extremely reduced by deposits.

In addition to this, in some cases the integrity of the bow clamp of the tapping sleeve may be compromised by corrosion.

The sealing system between the main water pipe and the tapping sleeve comprising one or more sealing means, such as O-ring in groove, may also lack some of its pre-stress or be compromised in other way.

Prior art

NO 313472 B 1 relates to a tapping saddle comprising a housing for tensioning against a pipe, the housing having a throughgoing opening for drilling through a pipe wall, where a sealing ring is mounted in the housing in order to be pressed against the pipe wall around a hole to be drilled therethrough. In order to secure sealing, also if the housing is not completely tightened against the pipe, and also to compensate for the deformation of the pipe wall due to the force exerted by the sealing ring, the sealing ring is situated against a sleeve being shiftably provided in the housing and which can be influenced by a spring in order to be biased towards the pipe wall.

US 2008/0245433 Al relates to a lateral liner assembly that provides a seal of a transition between a lateral sewer line and a main sewer pipe. The lateral liner assembly comprises a main portion attached to a collar. A flange assembly is further attached to the collar to provide a rigid base for a seal.

The purpose of the invention

An object according to the present invention is therefore to provide a system and a method for excavation-free sanitation services of existing tapping sleeves, where one or more disadvantages of the prior art are eliminated or at least reduced.

Another object according to the present invention will be to provide a system and method for excavation-free sanitation services of tapping sleeves or similar on main water pipes with respect to the pressure integrity is made possible in a simple way and with a good, reproducible, robust and long-term stable result.

Still another object according to the present invention will be to provide a system and method for excavation-free sanitation services of tapping sleeves or similar on main water pipes with respect to the mechanical fastening of the branch pipe towards the main water pipe is made possible in a simple way and with a good, reproducible, robust and long-term stable result.

These objects are achieved with a system and method for excavation-free sanitation services of tapping sleeves of main water pipes as indicated in the following independent claims, where further features of the invention appear from the dependent claims and the description below.

Generally about the invention

In accordance with a first aspect of the present invention, there is provided a system and a method for excavation-free sanitation services of tapping sleeves or similar used for connection of one or more branch pipes to main water pipes which combines robustness, reproducibility and long-term stability with right cost picture.

Excavation-free sanitation services of tapping sleeves according to the present invention are provided by means of a pipe robot which is equipped with specially developed tools together with specially developed equipment together with jointing sleeves. Pipe robots with special tools and various introduced sanitation liners are known, for example, from CA 2.888.460 Al, where a casing stretched with a hardening material in the repair of a connection between a main pipe and a branch pipe. Unlike existing systems based on sanitation services of branching with liners, a jointing sleeve of a metallic material is used according to the present invention to obtain a sealing and structural integrity in a connection between a main water pipe and a branch pipe which is connected to this, where the connection is in the form of a tapping sleeve or similar. Before the introduction of the jointing sleeve for connecting and/or sealing of the connection between the tapping sleeve and the main water pipe, the tapping sleeves inner diameter is increased in a contact area, to which contact area a branch pipe again is connected to. An inner diameter of an opening or a hole in the main water pipe, which opens for a flow of water into the tapping sleeves is increased correspondingly. The work up of the contact area of the tapping sleeve may be accomplished in several ways. In an embodiment of the present invention grinding and/or metal cutting of the tapping sleeves contact area may be utilized. Another possibility may be to use different erosion techniques, both with and without added erosion agent. Unlike the prior art, as described in for example GB 2.432.383 A for use in oil and gas wells, the metallic sleeve according to the present invention is not used to seal the leaks in the walls of the pipes, but to restore mechanical integrity and to establish new sealing functions between the main water pipe and the inner diameter of the tapping sleeve. This interaction between the main water pipe and the tapping sleeve may according to the present invention be envisaged provided with one of the following methods.

In a variant of the present invention a threaded portion is worked up over the whole or a part of an area of a house of the tapping sleeve which is formed with an enlarged internal diameter, where the threaded portion may comprise one or more threads. The corresponding area of the jointing sleeve's outer diameter is prepared with a threaded portion, over at least a part of a length of the jointing sleeve, where the threaded portion may comprise one or more threads. The inner diameter in a region of the housing of the tapping sleeve is increased by various techniques, such as with machining with one or more tools mounted on a pipe robot. At least one thread is then cut in the worked-up area. The jointing sleeve wholly or partly provided with thread or threads is then screwed into the tapping sleeve by means of a torque tool provided on the pipe robot.

In a further variant of the present invention it may be used a substance or a material that achieves its mechanical strength and/or adhesion in that it undergoes a curing process. Said substance or material is injected from the pipe robot via a hose, which through one end is connected to one or more holes formed in the jointing sleeve and through an opposite end is connected to the pipe robot. After the injection of the substance in an area which is provided between the jointing sleeve and the tapping sleeve, when the jointing sleeve is arranged in the tapping sleeve, a curing process is followed that creates mechanical strength and provide waterproofing properties.

In a further variant according to the present invention, there may be used a substance or material which achieves its mechanical strength and/or adhesion by undergoing a phase change, typically between liquid and solid state. This substance or material may be applied the jointing sleeve at the production or manufacture of the jointing sleeve, or it may be supplied as a step in the assembly of the jointing sleeve. In order to change the state of the substance or material from solid to liquid phase, an electric heat source can be used in the form of resistive heating. The resistive heating may be provided, for example, by a filament element or a heat film firmly disposed between the jointing sleeve and the tapping sleeve when the jointing sleeve is arranged in the tapping sleeve, or in the phase shifting substance or material itself.

In a further variant according to the present invention, the connection and/or seal between the jointing sleeve and the tapping sleeve may be provided by increasing a whole or part of the outer diameter of the jointing sleeve by using one of the following techniques:

The outer diameter of the jointing sleeve can be increased by using an internal and radially expanding mandrel. The behavior of said mandrel may typically be based on two or more sliding inverted wedge shapes. In that the wedge surfaces in the mandrel are driven linearly against each other, the desired outward radial force occurs. A linear force which is necessary to drive the wedge surfaces of the mandrel against each other, may typically be provided by turning a rotational motion into a linear motion, for example, by using one or more threads or the like. The necessary linear force may also be provided by a hydraulic piston function. One skilled in the art will know that linear power can be provided in a further manner, whereby this is not discussed further herein.

The outer diameter of the jointing sleeve may be increased by utilizing hydroforming of the jointing sleeve in that by applying a high hydraulic pressure to the inner diameter of the jointing sleeve, which causes at least a part of the material in the jointing sleeve to exceed the yield point of the material and permanent deformations occur in the jointing sleeve. The hydraulic pressure against the inner diameter of the jointing sleeve is caused by the passage of a high-pressure fluid into a gap provided between the inner diameter of the jointing sleeve and at least another body, for example in the form of a cylinder which is temporarily disposed inside the jointing sleeve. Said at least one body is designed for the purpose of achieving a compression strength that far exceeds the expansion strength of the jointing sleeve. In addition, the area of the jointing sleeve which is to be shaped, must be limited through a first and second delimitation, so that a hydraulic pressure can be established in the space formed and defined by an inner diameter of the jointing sleeve, the at least one body and the first and second boundaries. The hydraulic fluid itself is typically passed from the pipe robot to the jointing sleeve through a hydraulic hose.

The outer diameter of the jointing sleeve may be increased by subjecting the jointing sleeve to an axially directed force which causes the yielding point of the material to be exceeded over at least a portion of the length of the jointing sleeve. The required power of this compression can typically be provided by a hydraulic piston function or a thread combination.

In an alternative embodiment, the connection between the material of the tapping sleeve and the jointing sleeve may be provided by one or more longitudinal grooves or recesses formed over whole or part of the outer diameter of the jointing sleeve. The tightening and/or connection function of the grooves is activated by pressing the jointing sleeve in a linear manner in place internally in the tapping sleeve by means of a linear force provided by the pipe robot.

In an alternative embodiment, the connection between the tapping sleeve and the jointing sleeve may be provided by one or more longitudinal elevations or protrusions formed over whole or part of the outer diameter of the jointing sleeve. The tightening and/or connection function of the grooves is activated by linearly pressing the jointing sleeve in place by a linear force provided by the pipe robot.

In an alternative embodiment, the connection between the tapping sleeve and the jointing sleeve may be provided by one or more longitudinal recesses formed over whole or part of the inner diameter of the material. The tightening and/or connection function of the recesses is activated by linearly pressing the jointing sleeve in place by a linear force provided by the pipe robot.

In an alternative embodiment, the connection between the tapping sleeve and the jointing sleeve may be provided by a melting and joining of the two materials in the jointing sleeve and the tapping clamp. Such a material for melting may initially be firmly connected to the outer diameter of the jointing sleeve. It may also in a broader sense be used a flux material.

The present invention is advantageous in comparison to other solutions in that it enables the machining of tappings/tapping sleeves resulting in renewed integrity. The system comprises the use of at least one pipe robot for work up of the tapping sleeve with regard to deposits and other preparation. The pipe robot is also equipped with one or more special tools for positioning and activating of the jointing sleeve. A system in accordance with the present invention will advantageously enable, inter alia:

A long-term stable connection with high integrity

A repeatable process

A correct cost picture

A tight tapping connection

- A tapping connection with the same flow cross section as originally.

The method for excavation-free sanitation services of a tapping sleeve which is connected to a main pipe with at least one branch pipe according to the present invention may, prior to the renovation of the tapping sleeve, first comprise shutting off the main conduit and at least one of its ends, opening a suitable connection in relative proximity to the branch pipe which is to be refurbished and thereafter using a tool from a pipe robot, which pipe robot has been driven into the main pipe, to remove deposits in the tapping sleeve and in an opening in the main pipe under the tapping sleeve. After removal of the deposits in the tapping sleeve and the main pipe, a tool from the pipe robot can be used to increase the inner diameter of the tapping sleeve in a connection area between the tapping sleeve and the main pipe/branch pipe, whereafter a tool from the pipe robot is used to process a contact area in the tapping sleeve so as to provide a connection to a jointing sleeve. Thereafter, a tool can be used from the pipe robot to increase an outer diameter of the jointing sleeve in a contact area of the jointing sleeve, after which a tool from the pipe robot can be used to process the contact area of the jointing sleeve in order to provide a connection to the tapping sleeve, and then to use a tool from the pipe robot to connect, through the contact areas of the tapping sleeve and the jointing sleeve, the tapping sleeve and the jointing sleeve.

In addition, during the step of increasing the inner diameter of the tapping sleeve and the jointing sleeve, in a connection area, this may include grinding and/or machining of the contact area of the tapping sleeve.

Instead of grinding and/or machining of the contact area of the tapping device, different erosion methods may be used to process the contact area of the tapping sleeve towards the jointing sleeve and for insertion of it, both with or without added erosion agent. During the step of processing the contact area of the tapping sleeve, a threaded portion may be worked up in the contact area of the tapping sleeve.

The outer diameter of the jointing sleeve may be achieved by using a radial expanding mandrel, hydraulic pressure (hydroforming) or hydraulic piston.

Instead of deformation of the jointing sleeve or press-fitting of this, hardened materials may be used, for example curing or melting materials in connection with the fixing of the sleeve. During the step of processing the contact area of the jointing sleeve, a threaded portion may be worked up in the contact area of the jointing sleeve.

In an alternative embodiment, the contact areas of the tapping sleeve and the jointing sleeve may be formed with one or more longitudinal grooves.

Detailed description of the invention

In order to give a better understand of the various technical features and functions of the present invention, an example description of several embodiments is given below. The description is given with reference to the drawings, in which

Figure 1 shows a tapping sleeve which the solution of the present invention can be used with,

Fig. 2 shows a schematic diagram of a jointing sleeve and a part of a tapping sleeve where a thread is used,

Figure 3 shows a schematic diagram of the jointing sleeve and a part of the tapping sleeve where a chemical is used,

Figure 4 shows a schematic diagram of the jointing sleeve and a part of the tapping sleeve where a chemical substance is used which changes from liquid to solid form in dependence on temperature,

Figure 5 shows a schematic diagram of an embodiment according to the present invention using a hydroforming principle, Figure 6 shows a schematic diagram of an embodiment according to the present invention, using a wedge-based expansion principle,

Figure 7 shows a schematic diagram of an embodiment according to the present invention, wherein axial compression of the jointing sleeve is used,

Fig. 8 shows a schematic diagram wherein the jointing sleeve is provided with external grooves,

Fig. 9 shows a schematic diagram wherein the jointing sleeve is provided with external elevations,

Fig. 10 shows a schematic diagram wherein it on an inner side of the tapping sleeve is provided elevations, Fig. 11 shows a schematic diagram wherein it on an inner side of the tapping sleeve is provided internal grooves, and

Fig. 12 shows a schematic diagram wherein a material melting at a lower melting point is provided around an outer circumference of the jointing sleeve sensor.

Figure 1 shows a typical tapping sleeve 1 which is intended to be refurbished according to the system and the method for excavation-free sanitation services of tapping sleeves according to the present invention. A tapping sleeve 1 is used when a main pipe is to be connected to a branch pipe (not shown), so that water can flow from the main line and out to the branch pipe (not shown), or vice versa.

When the tapping sleeve 1 is connected to the main pipe 2 and the branch pipe (not shown), a hole formed in the main pipe 2 and the branch pipe will be levelled with a throughgoing bore B in the tapping sleeve 1.

Figure 2 shows a cross-section of a tapping sleeve 1 according to figure 1 which is connected to the main pipe 2, where a thread 20 in the throughgoing bore B of the tapping sleeve 1 is incorporated by a tool-equipped pipe robot (not shown). A jointing sleeve 21 provided with external thread is brought into engagement with the thread portion 20 by means of the pipe robot. The connection between the jointing sleeve 21 and the tapping sleeve 1 occurs only after any deposits in the tapping sleeve 1 and the main pipe 2 have been removed and the jointing sleeve 21 and the tapping sleeve 1 have been processed. The further figures show alternative embodiments and designs of the tapping sleeve 1 and the jointing sleeve 21, for the purpose of forming a connection between the tapping sleeve 1 and the main pipe 2 by means of the jointing sleeve 21.

Figure 3 is a sectional view of a tapping sleeve 1 according to figure 1, where a chemical substance 30 is used and introduced into a gap provided between the jointing sleeve 21 and the tapping sleeve 1 when the jointing sleeve 21 is arranged in the tapping sleeve 1 by a pipe robot (not shown) equipped with injection equipment. As a result of the chemical reaction, the desired grip occurs between the jointing sleeve 21 and the material 32 in the tapping sleeve 1. Figure 4 shows that the jointing sleeve 21 around an outer circumference over at least a portion of the length of the jointing sleeve 21 is provided with a layer of material 41 which changes from solid to liquid depending on the temperature at which the material 41 is exposed to. The jointing sleeve 21 is internally fitted with an electrically heated element 42. After insertion of the jointing sleeve 21 into the tapping sleeve 1, the element 42 is activated such that the material 41 alternates from solid to liquid and back to solid with subsequent grip between jointing sleeve 21 and tapping sleeve 1.

Figure 5 shows a further variant of the present invention wherein hydroforming of the jointing sleeve 21 is used to shape this after the radially surrounding cavity in the tapping sleeve 1. The pressure is supplied through a port 52 of an inner and central body 54 from the pipe robot. Seals between the inner and central body 54 and the sealing surfaces 53 restrict the pressure that provides the hydroforming of the jointing sleeve 21. The sealing function between the inner and central body 54 and the sleeve 21 may be provided in a variety of ways. For example, a chemical compound or solder is used which is broken by removal of the inner and central body 54 after carrying out of the hydroforming. The temporary sealing may also be provided by the fact that in the sealing surfaces 53 are formed with areas that create a metallic sealing.

Figure 6 shows a further variant of the present invention where opposite wedge surfaces 61 and 62 arranged internally in the jointing sleeve 21 are used to create the expansion force to form the jointing sleeve 21 from a force which is applied towards a surface 63. Figure 7 shows a further variant of the present invention where a forge piston 71 and an applied force 72 are used to clench the jointing sleeve 21 to an increased diameter.

Figure 8 shows a further variant of the present invention, where the jointing sleeve 21 is provided with elevations 81 around whole or part of an outer circumference of the jointing sleeve 21, which is pushed by a force applied from the pipe robot to make the connection 82 between the tapping sleeve 1, the main pipe line 2 and the jointing sleeve 21.

Figure 9 shows a further variant of the present invention, where the jointing sleeve 21 is provided with elevations 91 around a whole or parts of an outer circumference of the jointing sleeve 21, and at least over a portion of the length of the jointing sleeve 21, which is pushed by a force applied by the pipe robot to make the connection 92 between the tapping sleeve 1, the main pipe line 2 and the jointing sleeve 21. Figure 10 shows a further variant of the present invention, where it on an inside of the tapping sleeve 1, in the throughgoing bore B, are provided internal elevations 101, which, after introduction of the jointing sleeve 21, creates the desired connection 102 between the jointing sleeve 21 and the tapping sleeve 1. Figure 11 shows a further variant of the present invention, where it on an inside of the tapping sleeve 21, in the throughgoing bore B, are provided internal indentations 111, which, after introduction of the jointing sleeve 21, creates the desired connection 112 between the jointing sleeve 21 and the tapping sleeve 1. Figure 12 shows a further variant of the present invention, where it around an outer periphery of the jointing sleeve 21, and at least over a portion of the length of the jointing sleeve 21, is arranged a material 121 with a lower melting point than the jointing sleeve 21, and where a heat source 122 brings this material above the fusion temperature by, for example, electrical or chemical energy supply. After that the temperature falls below the melting point, the desired connection occurs between the jointing sleeve 21 and the tapping sleeve 1.

It is to be noted that further embodiments are possible. The scope of the invention is limited by the claims, and a person skilled in the art would be able to make modifications of the above examples without departing from the scope of the invention.