WO2008000474A2

WO2008000474A2 - Device and method for easily inserting a long plastic tube into a duct via a shaft

Info

Publication number: WO2008000474A2
Application number: PCT/EP2007/005734
Authority: WO
Inventors: Franz-Josef Püttmann
Original assignee: Tracto-Technik Gmbh & Co. Kg
Priority date: 2006-06-30
Filing date: 2007-06-28
Publication date: 2008-01-03
Also published as: WO2008000474A3; DE102006030802B4; DE102006030802A1

Abstract

The invention relates to a positive guiding means and a method for inserting substantially cylindrical tubes into the ground, the tube being guided along a curved path and being deformed before or when entering the curved path.

Description

"Device and method for easily inserting a long plastic tube into a channel via a well"

The invention relates to a positive guide and a method for horizontal introduction of flexible pipes in the ground, in particular of long pipes over a cramped access to a ground channel from the earth's surface.

Pipes to be buried in the ground must comply with certain static requirements, as the pipes are subject to various stresses during laying and also in the soil, in particular the compression pressure of the soil. This applies to pipes to be laid in newly created tracks as well as to pipes to be inserted in existing old pipes. The requirements usually require the use of stable, statically resilient materials. Here come tube materials such as metals, stoneware, concrete, cast iron or steel in particular, but also stable plastics such as PP (polypropylene), PVC (polyvinyl chloride) and many (PE) polyethylene used. With the use of such pipe materials is associated with a low flexibility of the pipes, which comes in particular when laying the pipes to fruition. Often, the pipe from its initial position on the earth's surface in an offset horizontal existing or to create track in the ground on tight curved paths to bring, with certain bending radii, depending on the pipe material, must not be exceeded. Such bending radii are specified, for example, in DVGW, Worksheet GW 323. In urban canals with their narrow deep manholes, the curve from the earth's surface into the route axis is characterized by particularly narrow curves. With the known methods and with materials suitable for such routes laying over the curved paths is not possible due to the exceeding of the maximum permissible bending radii. In practice, need Therefore, with great effort corresponding pits are dug, either having a length corresponding to that of the entire tube and allow insertion of the tube in the axis of the pipe line or provided in the form of oblique introduction pits, which comply with the bending radius, so that the allowable elongation of Pipe material is not exceeded. But because of the boundary conditions that is

Excavation of such pits often not possible. With correspondingly stable pipe material, such curved tracks can not be overcome (for example in the case of steel) or only under extreme material load (for example in the case of plastic). In practice, therefore, either the pits are designed so that correspondingly long pipe sections can be inserted directly into the laying axis or, if the pit is not available for a change (as is the case, for example, with manholes or manholes), the pipe sections designed according short, so that the pipe is adapted to the pit. In both cases, the pipe section to be laid is inserted into the laying axis and connected in constant repetition of the process with the already laid pipe section. In both cases, a considerable cost arises.

In practice, so-called short pipes are used in such shafts mainly, which are slightly shorter than the shaft (for example, manhole) and so can be aligned in the depth of the shaft in the horizontal position for insertion into the channel and connected to other pipe sections. Since the introduction of short tubes is time consuming and expensive, various technologies have been developed to facilitate the connection of the pipe sections and to make optimum use of the space available in the shaft. However, these all have the common disadvantage that the short tubes require a repetitive connection process and increases the risk of leaks due to the many compounds. Thus, methods have been developed to connect the pipe sections by means of hydraulic pushing or pulling devices. To use the space in the shaft, the drive units were arranged in the pipe line or in the already laid pipe.

For plastic pipes of sufficient strength, the minimum bending radius is specified. This is the practical requirements for a continuous and therefore inexpensive pulling the pipes, especially in manhole structures, usually not fair. Furthermore, flexible fabric structures were developed, for example, fleece or fiberglass materials that can be introduced via curved paths without difficulty. These can be soaked as described for example in DE 38 19 657 A1, with synthetic resin and are brought depending on the material and technology by applying water vapor in its final form and cured. Age- Native curing also UV radiation in the route has become known (DE 44 45 605 A1).

At the beginning of the eighties, pipes were developed, which could be folded in production and distributed in folded form on reels and correspondingly introduced into the channel. This to achieve that the channel is completely lined. The problem was holding the pipes in the folded form or returning the pipes to their original shape. In Swedish Patent Specification 368 435 a method is described in which the tube is held together in the folded state by means of wires or bands, which after retraction of the

Tube were removed. The difficulties associated with attaching and detaching the wires or tapes were overcome by using an initially cylindrically extruded and then folded reel-rolled tube, which was then returned to its original shape by heating after being drawn in (DE 35 19 439 A1). This procedure is still used today. The tubes are usually available as drum products and have been further developed with various plastics. With main lines of, for example, 200 mm diameter can be achieved with certain materials bending radii of 900 mm. The corresponding standards and guidelines for laying such pipes are described in DVGW Worksheet GW 320 II - "Rehabilitation of gas and water pipelines with PE-HD process by relining without annulus, requirements, quality assurance and testing" as well as the CEN TC 155 Wl 209 - "Plastic piping systems for the renovation of buried non-pressure drainage networks (free-flow lines)", Part 1. General and Part 3. Close-Fit üning niedergelegt.

EP 0 341 941 A1 discloses a method for introducing PE pipes into the ground, in which the pipe is stretched before being pulled in and thereby reduced in diameter in order to allow pipes having a final diameter to be drawn in, which is almost equal to the diameter of the old pipe and thereby to allow as complete as possible filling the old pipe. The stretched tube is thereby drawn into the route and relaxed after drawing, whereby the circular cross-section increases again. This method is limited in its curve. The tubes are also reduced in diameter only to fit into the old pipe slightly larger old pipe. The invention is therefore based on the problem of avoiding at least one of the disadvantages of known systems for introducing flexible pipes into the ground.

The problem is solved by a forced operation and a method according to the independent claims. Further advantageous embodiments will be apparent from the dependent claims.

The invention is based on the idea to introduce substantially cylindrical long tubes on a curved path from the earth's surface into the soil and to overcome the insurmountable for the cylindrical long tube curve in that the tube is brought into the soil during introduction into the mold (deformation) in which the forces acting on the pipe wall are reduced in relation to the forces acting on a circular pipe cross-section. Thus, an advantageous for the curve guide pipe cross-section is created if necessary, without that the

Stockpiling of folded pipes is required. The deformation can be carried out by means of the device according to the invention, e.g. can cause the known folding of the tube.

The advantageous for the curve guide tube cross-section facilitates the bending of the tube, as it takes place in the curved section, by the compression and elongation of the pipe wall is reduced. This is due to the fact that the compression and elongation of the pipe wall increases with increasing distance from the axis of rotation, since the difference between the circle radii of the outer circle becomes larger to the inner circle of the pipe wall in the curved path.

According to the invention, "pipe" is to be understood in particular to mean a longitudinal body which has a cavity and a wall of any desired material.

By "deformation" or "deformed cross-section" is meant any cross-section that is altered (deformed) with respect to the original shape. Under oval to U-shaped cross section is to be understood a cross-section, which may be formed from oval to flat to U-shaped.

"Curve sections" means at least one section on the way from the earth's surface to the final laying position, which deviates from the straight line. The present invention makes it possible to avoid both stowage of the known folded tubes (often referred to as U liner) and assembly of tube sections in the pit or pit and to continuously draw long tubes of cylindrical cross section into the ground, even if cramped space conditions are given. The laid pipe is uniform and therefore has no weaknesses or leaks in comparison to the individually assembled short pipe sections with the corresponding number of transitions.

The pipe can be fixed on site with the aid of the device according to the invention, e.g. are deformed immediately before entering the curved path and then returns, preferably on entering the channel, back to its original shape.

By "returning" the tube is meant the process which returns the tube substantially to its original shape.

Preference is given to pipes with memory effect used, which automatically reset after leaving the forced operation. For example, the pipe can then once again have a circular cross-section just before or when it enters the route. Preferred pipe material is polyethylene (PE).

Preferably, the invention with the aid of a device according to the invention (forced operation) is realized, which can be designed so that a tube with previously circular cross-section is brought out of its shape when entering the forced operation (deformation). In this case, a shape can be generated over a short distance, which leads to a strong reduction of the material load in the curved path. The tube can be made, for example, in an oval to U-shaped cross-section, in which only a slight compression of the inner tube wall section and a small elongation of the outer tube wall section occurs in the curved path. In principle, a deformation is preferred in which the pipe wall sections remote from the axis of rotation are approximated. This can vary from an oval or increasingly flat configuration to an overstretched, i. U-shaped configuration of the cross section can be achieved

The positive guide may have rollers to reduce the frictional resistance and thereby have both rollers for the deformation of the tube and / or rollers for the return of the tube. The setting can also be done via a conical ring. In such a case, the pipe can already immediately after returned to its original form when entering the earth. Regardless of the forced operation can be designed as a guide tube.

To assist in deformation and / or re-dividing, the temperature of the tubing may be increased, e.g. by warm air or radiation is supplied from the inside and / or outside.

Alternatively or additionally, the tube can be deformed by negative pressure or the deformation process of the forced operation can be assisted by negative pressure. For this purpose, the otherwise sealed tube can be connected to a vacuum pump. After insertion of the pipe into the ground, the pipe can be vented so that it moves back to its original shape.

The return of the tube to its original shape can also be achieved by applying pressure medium, such as e.g. Compressed air or can be achieved or supported by mechanical means.

The forced operation can be produced without special design effort and use it easily for any construction site situations and waveforms. Of the

Transport of forced guidance to the site is possible with a compact design without any special effort. The forced operation can also be configured as a modular system. In this case, both the forced operation with and the forced operation without rollers consist of two individual modules, which are fixed against each other or otherwise via corresponding rails to a defined curve

To ensure the deformation of the pipe.

The invention is illustrated below with reference to an embodiment explained in more detail in the drawing.

In the drawing show:

Fig. 1a / b is a schematic representation of the positive guide according to the invention with a deformed tube therein in the curved path;

Fig. 2 shows the forced operation of Fig. 1 in a manhole and Fig. 3 shows a preferred embodiment of the positive guidance according to the invention with rollers for deformation and for returning the tube shape.

A manhole 1 has a surface-side vertical channel opening 2 (typically closed by a manhole cover) and channel-side horizontal openings

3 on. The channel-side openings each represent pipe ends of the old pipe and define the axis (A) into which a new pipe 4 is to be introduced.

The new pipe 4 is first ground surface side outside of the shaft 1. To bring the pipe 4 through the channel opening 2 through the shaft 1 in the axis of the channel openings 3, the tube must be moved twice with a change in direction over a curved path. When introducing the tube 4 into the channel via the shaft 1, this results in two 90 ° curves (I, II). In Fig. 1b, an alternative embodiment is shown, in which the tube 4 is introduced vertically into the shaft 1, so that only a 90 ° curve is to be overcome at the bottom of the shaft.

The respective curves are overcome by the tube by means of a positive guide 5 by the tube is deformed before entering the curve area and so can pass through the curved area under reduced material load. When or after entering the channel axis A, the tube 4 due to its material properties (memory effect) assumes its original shape with a cylindrical cross-section substantially again, wherein the outer tube diameter is smaller than the inner diameter of the channel.

In Fig. 2, an embodiment is shown in which the cam guide and deformation in the curves I and Il is formed by a guide slot forming guide rails 7, 9, which compress the tube 4 at its outer and inner radius, so that the pipe wall sections approach , As a result, the radii of the pipe wall sections are aligned in the curved path. In the embodiment shown in FIG. 3, rollers 11 to 13 are used for the deformation and

Return the tube 4 for use.

When the tube 4 enters the first curve region I of the shaft 1, the tube is first compressed (deformed) with the aid of the rollers 11. The rollers 12a and 12b ensure that the tube 4 passes through the curved area while retaining its deformed shape. The rollers further cause a reduction in the coefficients of friction when passing through the positive guide 5 and a further reduction in the material load. In the output range of the forced operation 5 and After the second curve II, rollers 13 or a conical ring 14 (FIG. 2) cause the tube 4 to return to its original shape or to support the material-related resetting.

Claims

claims:

1. Forced guidance for introducing into the soil pipes, characterized by a guide profile, in which the tube is deformed and then undergoes a change in direction.

Second positive guide according to claim 1, characterized by rollers (11, 12) for guiding and / or deforming the tube.

3. Forced guidance according to one of the preceding claims, characterized by rollers (13) for returning the tube.

4. Forced guidance according to claim 1, 2 or 3, characterized by a device for increasing the temperature of the tube material.

5. Forced guidance according to one of claims 1 to 4, characterized by a conical ring (14) for returning the tube (4).

6. Forced guidance according to one of the preceding claims, characterized by a modular structure.

7. Forced guidance for introducing into the soil pipes, characterized by at least one deformation region (7, 9) with a guide profile, in which the tube (4) is deformed and then undergoes a change in direction.

8. A method for introducing substantially cylindrical tubes (4) into the soil, in which the tube is guided on a curved path (I, II), characterized in that the tube (4) deformed before or upon entering the curved path becomes.

9. The method according to claim 8, characterized in that the tube (4) is brought back into its original shape during or after entering the channel axis (A).

10. The method according to any one of the preceding Verfahrensansprüche, characterized in that the guidance and / or deformation of the tube (4) by means of rollers (11, 12).

11. The method according to any one of claims 8 to 10, characterized in that the temperature of the tube material is increased to support the deformation and / or the Rücksteilens.

12. A method for introducing substantially cylindrical pipes in the soil, in which the tube (4) is guided on a curved path, characterized in that the tube in a positive guide (5) through the curved portion (I, II) is guided.