CA2103686A1

CA2103686A1 - Drainage pipe

Info

Publication number: CA2103686A1
Application number: CA002103686A
Authority: CA
Inventors: Hubert M. Drossbach
Original assignee: Individual
Current assignee: Drossbach GmbH and Co KG
Priority date: 1992-08-07
Filing date: 1993-08-06
Publication date: 1994-02-08
Also published as: DE4226157C1; DE59301625D1; NO932780D0; JPH06180023A; EP0583596A1; FI933489A; EP0583596B1; FI933489A0; NO932780L; ATE134235T1

Abstract

ABSTRACT OF THE DISCLOSURE

The invention pertains to a three-walled drainage pipe made of plastic, which may be used as a multi-purpose or partial drainage pipe, a smooth-walled inner pipe being surrounded by a corrugated pipe and welded to its wave troughs and having slit-like openings for the passage of drainage liquid, and in turn the corrugated pipe being surrounded by an outer pipe which is indented into the wave troughs and perforated only in the pipe crown area of the openings, the remainder of the outer pipe being smooth. The addition of an outer pipe provides better rigidity and increases the crushing strength while simplifying manufacture and making it cheaper.

Description

Drainage Pipe Thiq invention pertains to a plastic drainage pipe in accordance with the preamble to Claim 1.

Drainage pipes are mainly used in road construction and are laid along the side of the road in place of the customary ditche~ previously used. As a rule, such drain-age pipes are manufactured from plastic in finite lengths of 6 m for example.

In a known embodiment, the cross-section of the drain-age pipe is tunnel-shaped. The inner wall surface is smooth, as is most of the outer wall surface. Merely the upper part of the outer wall surface has furrows running parallel to the pipe axis in the area of which the pipe wall ha~ croqs slit3 in order to take in external water.
Such a drainage pipe has the advantage of a high drainage volume as a result of the smooth inner surface. This pipe is relatively heavy, however, because it has to have rela-tively large wall thicknesses in order to achieve a cer-tain rigidity, so that deflection i3 reduced during trans-port and adequate rigidity is achieved in the loaded state.
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These strength problems are solved by means of another known design of the cross-section of the drainage pipe : with the pipe having transverse waves over its entire length in whose wave troughs slit-like openings are cut in perpendicularly to the pipe axis. These transverse waves . give the drainage pipe greater rigidity with reduced wall " ~; :
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210~686 thickne~, but at the expen~e of the drainage volume, which reaches, based on the same diameter, only about two-third~3 of the drainage volume of the smooth pipes on account of the transver~e waves.

The tunnel ~hape of such drainage pipes ha~ the advan-tage of being easy to lay, because the level base of the pipe provides the correct installation position. On the other hand, however, tunnel-shaped drainage pipes can be manufactured only with a high tool outlay and result in problems in regard to the seal at the connecting area between two adjacent pipes.

Finally, double-walled pla~tic pipeR are known in which the inner pipe is smooth-walled and the outer pipe ha~ transverse waves. Both pipeY are connected to one another in the area of the wave troughs.

Such a double-walled drainage pipe is known from DE-OS
36 05 329 and can be u~ed a~ a multi-purpose, full, or partial drainage pipe consisting of a smooth inner pipe and a corrugated outer pipe, the corrugated pipe having two hollow strips running the length of the corrugated pipe which fill the wave trough~ and which are arranged in relation to one another in an angle of a = 120 related ~o the pipe axis and the slit-like openings are located only in the area enclosed by the angle a. These strips prevent the drainage liquid draining of f along the wave troughs and the location of the strip~ provides a good orientation aid for correct laying of the drainage pipe.
The webs cannot be broadened as de~ired with this two-wall - . . . .

3 21036~6 pipe, because otherwise the crushing strength would be too small .

It is the objective of this invention, therefore, to design a drainage pipe in such a way that it can be used a~ a multi-purpose or partial drainage pipe with markedly improved rigidity,which is less expensive to manufacture and provides better drainage.

This objective is solved through the invention ~pec-ified in Claim 1, preferred embodiment3 of the invention being described in the sub-claims.

The pipe ~ystem is provided with much greater rigidity by the addition of a third pipe forming an outer pipe.
Damage to the inner pipe resulting from it being laid in hard or lumpy materials like gravel is avoided. The con-nection to the surrounding filling material is improved.

The arrangement of the slit-like openings and their corresponding indentations in the outer pipe are al30 an orientation aid for the laying of round pipes. Round pipe~
are especially stable, withstand a high crushing force, can be laid easily, and can be connected easily with one another.

If no slit-like opening~ at all are provided, then the inventive three-wall drainage pipe can be used a~ a highly stable, impermeable sewer pipe.

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Moreover, in accordance with the invention the funnel-shaped impres~ion~ in the outer pipe are de~igned in ~uch a way that ~hey protect the water intake openings from becoming dirty and provide hydraulic advantage~ for carry-ing water.

In a preferred embodiment of the invention, there i8 a shaped, expanded, or ~prayed-on, or welded-on ~leeve at one end. A ~ealing ring can be inserted in a groove so that the drainage pipes are easily connected together axially with one another.

The invention is explained below in more detail u~ing an embodiment. The drawings show as follows:

Fig. 1 a top view of a drainage pipe, Fig. 2 a top view of a section of the drainage pipe, Fig. 3 a cro~s-section through a circular drainage pipe, Fig. 4 a vertical longitudinal section through a drainage pipe, Fig. 5 a-c various alternatives for openings, Fig. 6 a longitudinal cross-section in the area of the connection of two drainage pipes, ... ...
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:; ;: . ... ~, : , i~. 7 a longitudinal cross-section in the area of the connection of two pipes, one pipe having a welded-on sleeve.

The drainage pipe 1 illustrated in Fig. 1 consists of a three-wall pipe whose outer pipe is essentially smooth. In the upper area illustrated, the outer pipe 6 has indentations 9 which are shaped as groove-like depressions over an angle range of approximately 110-220, and preferably 120, in the circumferential direction. There are-openings 8 in the depressions which create a connection between the area surrounding the pipe and the interior of the pipe. There is a shaped, expanded sleeve 10 on one end into which the non-expanded end of another corresponding pipe section can be inserted. Preferably, there are no depressions in the outer pipe in the area of the sleeve.

The area of the non-expanded end of the pipe also has no depressions but merely a circular groove 11 in which an O-ring or a lip seal can be inserted so that when the non-expanded end is inserted into another pipe a tight connection is achieved. However, the groove is preferably formed in the sleeve at the other end of the pipe.

Figure 2 shows an enlarged partial view from Fig. 1 from which the funnel shape of the indentations 9 can be seen. The indentations follow the wave troughs of the middle pipe. Each indentation 9 contains three slits 8, which can be sunk, cut in, stamped in, or sawn in the traditional manner. More than 3 slits may also be used.

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6 ~103686 The funnel ~hape of the depressions in the outer pipe protects the water intake openings from becoming dirty and provides hydraulic advantages for the carrying of water.

Figure 3 shows a cross-section through a pipe in accordance with the invention. The inner pipe 2 i3 smooth in the longitudinal direction and ~urrounded by a corru-gated pipe 3 whose wave troughs 4 are each welded to the inner pipe 2. The wave peaks are connected, in particular welded, to another pipe surrounding the corrugated pipe 3 and which is essentially smooth in the longitudinal direction.
Figure 3 shows a sectional plane in which one wave trough of the corrugated pipe 3 is connected to the inner pipe 2.

In the upper area of the pipe, relative to the installa-tion po~ition, the outer pipe 6 is indented towards the inside and welded to one wave trough of the corrugated pipe in this area. Consequently, a threefold wall thick-ness at the sites of the indentations results. The open-ings 8 are located in this area.

The slits can be made in the drainage pipe either by means of sawing, stamping, or rotary cutting. Drill holes can also ~be provided, in which case it must be ensured, however, that in accordance with DIN 4262 at least 50 cm2 slit surface per metre remains.

The indentations in the outer pipe are preferably longitudinal depressions, however several depressions 210368~

located be~ide one another can be provided. It i~ especial-ly where the openings are drill holes that i~ can be pro-vided that the indentation~ in the outer pipe are point-shaped .

Figure 4 show~ a vertical section of an inventivepipe. It can be clearly seen that the outer pipe 6 i~
pressed into the wave troughs of the middle pipe 3 on the upper side of the pipe and is perforated at the ~ite~ 8.

Figures 5 a - c show various type~ of openings in the drainage pipe. Figure 5 a show~ an enlarged view of a ~imple ~lit. Figure 5 b ~how~ two parallel slits located in one wave trough in order to reduce the size of the individual ~lit. Finally, Figure 5 c ~how~ two parallel qlits between which the outer pipe al~o ha~ an elevation 15. The slit~ can be off~et to one another in the circum-ferential direction in all embodiments of Figure 5 in order to improve further the overall strength of the pipe.

Preferably, corre~ponding indentation~ of the outer pipe are found in every groove of the corrugated pipe. If the slit~ are large enough and there are enough of them, it can a~o be provided, for example, that only every second wave trough be connected with an indentation in the outer pipe.

Figure 6 showQ the connection between two drainage pipe sections. In this Figure the sleeve end of one drain-age pipe i~ expanded in ~uch a way that the non-expanded end of a drainage pipe can be inserted into the sleeve without ~ . :
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~103686 problems. It can be ~een once again in thi~ ca~e that the ~mooth-walled inner pipe is surrounded by a corrugated pipe which is welded to the inner pipe in the area of the wave troughs. The outer pipe 6 is smooth and i~ connected to the outer crown ~uxfaces of the corrugated pipe 3. The interior diameter of the sleeve end of the drainage pipe i8 slightly larger than the diameter of the non-expanded end.
Preferably, a sealing ring, for example an O-ring or a lip seal, can be inserted into a circular groove in the non-expanded end or into a crease 20 in the sleeve end, the groove being produced by pressing the outer pipe 6 over its entire circumference into a wave trough of the corru-gated pipe or being formed from a crea~e-shaped recess 20 of the inner pipe in the sleeve end (as illu~trated).

Figure 7 shows the design of a pipe with a welded-on sleeve, as is preferred with large diameters in particular because an expan~ion would mean a considerable expenditure of time and money in thi~ ca~e. The sleeve 16 i5 shoved a distance over the blunt cut-off end of a pipe and welded or ~prayed on. The sleeve is one-walled and ha~ an interior diameter which is ~lightly larger than the exter-nal diameter of the drainage pipe.

There is a ring-shaped closure 17, which guarantees that the leeve can be shoved onto the drainage pipe for a defined length.

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On the front end of the sleeve there i~ a circular crease 18 into which a sealing ring 19, in particular a lip seal, can be inserted. This type of ~leeve connection has the particular advantage that the drainage pipe can be manufactured in indefinite lengths without the end~ being given any special de~ign.

Due to the smooth outer pipe, it can be laid flu3h in concrete or cohesive gravel, guaranteeing a good connec-tion to the pipe so that water coming into contact with the drainage pipe cannot flow off laterally from it but almost all of it enters the openings 8 on the upper side of the drainage pipe.

The inventive pipes can be made fr,om polyethylene, polypropylene (which has a higher E-modulus ) and in speci-fic cases also from PVC. In order to manufacture an inven-tive drainage pipe, a double-walled pipe manufactured in accordance with the state of the art i~ surrounded with a third pipe by means of a further angular extruder head.
Immediately after exiting from the nozzle, the third pipe i9 indented either by means of mould stamps or mould par~s which move along with it. After being cooled in a water bath and~cleaned, the slits can be added to the pipe, it can be cut into lengths, and the sleeve formed in the known manner.

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Reference Number List 1 Drainage pipe 2 smooth-walled inner pipe 3 corrugated pipe 4 wave trough transverse waves 6 outer pipe 7 pipe axis 8 slit-like openings 9 indentation expanded cleeve 11 circular groove 13 bevelling 14 seal elevation 16 31eeve 17 closure 18 crease 19 sealing ring crease ....

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Claims

1. Drainage pipe, in particular for the drainage of subsoils, consisting essentially of a double-walled plastic pipe with a smooth-walled inner pipe and with a corrugated pipe surrounding the inner pipe and whose wave troughs are firmly connected to the inner pipe, the drainage pipe having openings in the wave troughs to allow the drainage liquid to pass through, wherein the drainage pipe is covered with another external, essentially smooth pipe outside of the area of the openings and which is pressed into the wave troughs of the corrugated pipe in the area of the openings and is connected with the corrugated pipe and perforated.

2. Drainage pipe in accordance with claim 1 wherein the drainage pipe is a partial or multi-purpose drainage pipe whose openings are distributed over a circumferential area of approximately 110-220°.

3. Drainage pipe in accordance with claim 2 wherein the drainage pipe has several perforations over a vertical angle range of approximately 120°.

4. Drainage pipe in accordance with claim 1 wherein the indentations of the outer pipe following the wave troughs of the corrugated pipe.

5. Drainage pipe in accordance with claim 1 wherein it has a circular groove in a non-expanded end area.

6. Drainage pipe in accordance with claim 1 wherein it has a circular groove in the interior of the sleeve end area.

7. Drainage pipe in accordance with claim 1 wherein it has a shaped, expanded, or sprayed-on, or welded-on sleeve on one end whose internal diameter is slightly larger than the external diameter of the drainage pipe throughout the remainder of the pipe area.

8. Drainage pipe in accordance with claim 5 or 6 wherein a sealing ring is inserted into the circular groove.

9. Drainage pipe in accordance with claim 1 wherein there are several slit-like openings located one behind the other longitudinally in the area of an indentation of the outer pipe.

10. Drainage pipe in accordance with claim 1 wherein the slit-like openings in one indentation are offset to one another in the circumferential direction.

11. Drainage pipe in accordance with claim 7 where the slit-like openings and the relevant indentation are shaped as holes.

12. Drainage pipe in accordance with claim 1 wherein there are several double slits with intermediate elevations in each indentation.