EP2383392A1

EP2383392A1 - Drain system

Info

Publication number: EP2383392A1
Application number: EP10161478A
Authority: EP
Inventors: Nikos Leontaridis
Original assignee: Pipelife Nederland BV
Current assignee: Pipelife Nederland BV
Priority date: 2010-04-29
Filing date: 2010-04-29
Publication date: 2011-11-02

Abstract

A drainage pipe system comprises a corrugated pipe (1) having a wall with alternating valleys (3) and crests (2) which extend in circumferential direction. The wall is provided with openings (4) and a filter sleeve (6) is positioned around the pipe (1). Said filter sleeve (6) is supported with respect to the pipe (1) by means of elongated members (5) which extend transversely with respect to the valleys and crests and which are connected, e.g. glued, adhered or welded to the crests (2). The filter sleeve (6) is supported on the outside of the elongated members (5).

Description

The invention is related to a drain pipe system, comprising a corrugated pipe having a wall with alternating valleys and crests which extend in circumferential direction, said wall being provided with openings, and a filter sleeve around the pipe.
A drain pipe system of this type is generally known. The filter sleeve thereof generally consists of a cloth or geotextile having a specific mesh size or range of mesh sizes in such a way that larger particles are filtered out and cannot reach the corrugated pipe wall openings. Ideally, the full surface of the geotextile is available for such filter action. This provides a large filter capacity. However, as soon as the geotextile is pressed against the pipe by the earth pressure, the filter action of the geotextile is limited to the spots where it overlies the perforations in the pipe. Thereby, the area of the geotextile which is available for filtration is severely limited, as a result of which the design filter capacity cannot be ensured in the long run. The function of draining the ground parcel is thereby hampered.
An example of further a drain system is disclosed in EP-A-29713 . The filter sleeve thereof consists of a fiber material, for instance coconut fibers. The purpose of this sleeve is to collect particles which are present in the groundwater, and to establish a specific particle size distribution through the thickness of the sleeve. Once a specific pattern of particles has settled through the thickness, a desired filter action is obtained. The larger particles, which bring the risk of choking the perforated pipe, are prevented from entering the drain system whereby a long-term proper draining action can be ensured.
The filter sleeve thus plays an important role in maintaining the desired particle distribution pattern around the perforated pipe. However, materials such as coconut fibers will generally decompose after some time, which causes loss of support for the particle distribution pattern. In case movements occur in the soil, said pattern is readily lost whereby the desired filter action is no longer ensured. As a result, the perforated drainage pipe runs the risk of being choked.
Another drain pipe system is disclosed in EP-A-33570 . Said prior art pipe system has a water permeable covering which consists of foil layers enclosing air filled cushions. The foil layers are provided with openings of a certain size, whereby particles of a specific size may collect between the foil layers so as to obtain a filtering effect. The disadvantage of such double foil layer with air filled cushions however is that it is vulnerable to damages caused by external forces exerted thereon, such as occur when installing the drain pipe system as well as thereafter as a result of ground forces. Moreover, the double foil layer with air filled cushions is costly
The object of the invention is therefore to provide a drain pipe system of the type described before which is of a more sturdy, economic design and which nevertheless provides a desired filtering capability. Said object is achieved by the filter sleeve being supported with respect to the pipe by means of elongated members which extend transversely with respect to the valleys and crests and which are connected, e.g. glued, adhered or welded to the crests.
In the drain pipe system according to the invention, the elongated support members create a distance between the pipe openings and the filter sleeve. The elongate support members prevent the filter sleeve from entering the valleys, which makes it possible to maintain a desired distance between the filter sleeve and the openings in the pipe wall. Thus, the full surface of the filter sleeve remains available for filtering purposes, also after the drain pipe has been buried in the soil and is exposed to earth pressures. Furthermore, the support structure has a certain rigidity, in such a way that the filter sleeve supported thereby can be held in the desired position with respect to the pipe so as to ensure long term draining capacity. As the support structure can be manufactured form e.g. plastics, it is ensured that a long term stability of the drain system is ensured. Any particles which pass through the filter sleeve are collected within the pipe for further discharge. Particles which pass through the filter sleeve are collected within the pipe for further discharge.
The filter sleeve can be supported on the outside of the elongated members; furthermore, the elongated members protrude in radial direction beyond the crests so as to obtain a relatively large distance between the filter sleeve and the pipe wall openings. Also, the valleys of the pipe wall are at a distance from the radial inner side of the elongated members. Thereby, the flow of liquid around the pipe wall and through the valleys is not impeded, such that the desired filter capacity can be obtained.
The elongated members may be arranged according to several shapes with respect to the pipe. According to a first possibility, the elongated members are parallel to the axis of the corrugated tube. According to another possibility, the elongated members are arranged helically at an angle with respect to the axis of the corrugated pipe. Preferably, the elongated members are regularly spaced in the circumferential direction of the corrugated tube. Such relative position of the elongated members ensure a uniform support of the filter sleeve around the pipe. The cross section of the elongated members may have any shape, provided the strength and rigidity thereof is sufficient to keep the filter sleeve at the desired distance from the holes in the pipe. For instance, the cross sectional shape may be square, rectangular, circular, oval etc.
The elongated members may comprise plastic strips. Preferable, said plastic strip comprise plasticized material. It then remains quite well possible to curve the pipe to such an extent that it can be rolled onto, and unrolled from, a spool. The material of the pipe and of the strips may comprise polyvinylchloride or polyethylene.
The porous sheets may comprise a woven, nonwoven, knitted or braided material. The perforated pipe may be circular, square, rectangular or a triangular in cross-section. Other shapes with more angles are possible as well. Furthermore, the filter sleeve may comprise more than one filter cloth or geotextile.
In summary, the support structure has a certain rigidity, in such a way that the filter sleeve supported by can be held in the desired position with respect to the pipe so as to ensure long term draining capacity.
The invention is furthermore related to a corrugated pipe for a drain pipe system according as described before, having a wall with alternating valleys and crests which extend in circumferential direction, said wall being provided with openings, as well as elongated members which extend transversely with respect to the ribs and which are adhered or welded to the crests.
The invention will furthermore be described with reference to the embodiment shown in the drawings.

Figure 1 shows the longitudinal cross-section according to II-II of figure 1 through the drain pipe system according to the invention.
Figure 2 shows the cross-section through the drain pipe system according to figure 1.

The drain pipe system shown in figure 1 comprises a so-called corrugated pipe 1 which consists of alternating wave crests 2 and wave valleys 3. In the wave valleys 3, drain openings 4 have been provided.
According to the invention, longitudinal strips 5 have been welded onto the wave crests 2. These longitudinal strips 5 are spaced in the circumferential direction of the pipe 1, as shown in figure 2. On the outside of the longitudinal strips 5, a filter sleeve 6, such as a filter cloth or a geotextile, has been fitted.
The longitudinal strips 5 ensure that the filter cloth or geotextile 6 is maintained at a distance from the wave valleys 3, in particular from the holes 4 therein, such that the full surface of the filter cloth or geotextile 6 can maintain its filtering action.

Claims

Drainage pipe system, comprising a corrugated pipe (1) having a wall with alternating valleys (3) and crests (2) which extend in circumferential direction, said wall being provided with openings (4), and a filter sleeve (6) around the pipe (1), characterized in that the filter sleeve (6) is supported with respect to the pipe (1) by means of elongated members (5) which extend transversely with respect to the valleys and crests and which are connected, e.g. glued, adhered or welded to the crests (2).
Drainage pipe system according to claim 1, wherein the filter sleeve (6) is supported on the outside of the elongated members (5).
Drainage pipe system according to claim 1 or 2, wherein the elongated members (5) protrude in radial direction beyond the crests (2).
Drainage pipe system according to any of the preceding claims, wherein the valleys (3) are at a distance from the radial inner side of the elongated members (5).
Drainage pipe system according to any of the preceding claims, wherein the elongated members (5) are parallel to the axis of the corrugated pipe (1).
Drainage pipe system according to any of claims 1-4, wherein the elongated members are arranged helically at an angle with respect to the axis of the corrugated pipe.
Drainage pipe system according to any of the preceding claims, wherein the elongated members (5) are regularly spaced in the circumferential direction of the corrugated pipe (1).
Drainage pipe system according to any of the preceding claims, wherein the elongated members (5) comprise plastic strips.
Drainage pipe system according to any of the preceding claims, wherein the elongated members (5) comprise plasticized material.
Drainage pipe system according to any of the preceding claims, wherein the openings (4) are in the valleys (2) of the corrugated pipe (1).
Corrugated pipe (1) for a drainage pipe system according to any of the preceding claims, having a wall with alternating valleys (3) and crests (2) which extend in circumferential direction, said wall being provided with openings (4), as well as elongated members (5) which extend transversely with respect to the crests (2) and which are adhered or welded to the crests (2).