INSTALLATION AND METHOD FOR MANUFACTURING DRIP IRRIGATION PIPES

Abstract

The invention concerns an installation for manufacturing a drip irrigation pipe (8) formed of a pipe (8) provided with drippers (4), including a dripper feed station (37), followed by an extrusion station (10), including an extrusion head (14) producing a tubular blank (22) and means for welding the drippers (4) to the inner wall of said blank (22), characterized in that the dripper welding means (4) include a support surface (50) and a counter-support surface (56) between which the drippers (4) are pressed against said tubular blank (22) so as to be welded thereto, said support (50) and counter-support (56) surfaces being arranged upstream of the calibrating means (24).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be better understood in light of the following detailed description of an example embodiment of the installation according to the invention, this example being given purely by way of illustrating and non-limiting example, with reference to the annexed drawing, in which:

FIG. 1 is a schematic diagram of a drip type irrigation pipe manufacturing installation according to the invention;

FIG. 2 is an axial cross-section of the extrusion head according to the invention; and

FIG. 3 is a partial enlarged view of a transverse cross-section of said extrusion head.

Claims

1. A method of manufacturing a drip irrigation pipe formed of a pipe provided with drippers, comprising the following main steps: providing a dripper feed station, and an extrusion station including an extrusion head, calibrating means and means for welding the drippers to the inner wall of said pipe,continuously forming a tubular blank using said extrusion head,calibrating said tubular blank using calibrating means,conveying said drippers inside the tubular blank using the dripper feed station, andwelding said drippers upstream of said calibrating means using said welding means.

2. The method according to claim 1, wherein said drippers are welded inside or in immediate proximity to said extrusion head.

3. The method according to claim 2, wherein the extrusion head includes an extrusion channel generating said tubular blank and is associated with a support surface arranged in proximity to the exit of said extrusion channel, and wherein said dripper feed means include a counter-support surface, said drippers being pressed between said surfaces against said tubular blank in order to be welded thereto.

4. The method according to claim 1, wherein the extrusion head includes an extrusion channel and an inner mandrel forming a cylindrical portion whose wall is thinned in proximity to the exit of the extrusion channel, wherein the welding is carried out at the exit of the extrusion channel.

5. The method according to claim 1, wherein said drippers are connected to each other via the body thereof made in a single piece having the shape of a continuous band.

6. An installation for manufacturing a drip irrigation pipe provided with drippers, including a dripper feed station, followed by an extrusion station including an extrusion head producing a tubular blank, means for calibrating said tubular blank and means for welding the drippers to the inner wall of said blank, wherein the dripper welding means include a support surface and a counter-support surface between which the drippers are pressed against said tubular blank in order to be welded thereto, said support and counter-support surfaces being arranged upstream of the calibrating means.

7. The installation according to claim 6, wherein said dripper feed station is arranged to convey said drippers between said surfaces, the distance between said surfaces being selected such that said drippers are pressed against the tubular blank between said surfaces.

8. The installation according to claim 6, wherein said support surface is coupled to the extrusion head and wherein said counter-support surface is arranged in immediate proximity to the extrusion head, opposite said support surface.

9. The installation according to claim 6, wherein said support surface is secured to the extrusion head and wherein said counter-support surface is arranged inside the extrusion head, opposite said support surface.

10. The installation according to claim 9, wherein said extrusion head includes a die formed of an outer mandrel and an inner mandrel arranged together to define an extrusion channel wherein said tubular blank is formed, said support surface being located at the exit of the extrusion channel, substantially parallel to said counter-support surface.

11. The installation according to claim 10, wherein said inner mandrel and said outer mandrel each include a cylindrical portion respectively engaged in one another so as to define at least in part said extrusion channel, the wall of the cylindrical portion of the inner mandrel being thinned in proximity to the exit of the extrusion channel.

12. The installation according to claim 11, wherein the wall of the cylindrical portion of the inner mandrel has a thickness comprised between 0.1 mm and 1 mm in proximity to the exit of the extrusion channel.

13. The installation according to claim 11, wherein the inner surface of the cylindrical portion forms a small angle α with said support surface.

14. The installation according to claim 11, wherein said cylindrical portion of the inner mandrel is shorter than said cylindrical portion of the outer mandrel, so that the end of the cylindrical portion forms said support surface.

15. The installation according to claim 11, wherein the dripper feed station includes a guide support engaged in said inner mandrel as far as the height of said support surface, the surface located opposite said support surface forming said counter-support surface.

16. The installation according to claim 11, wherein said inner mandrel includes a groove made in said cylindrical portion, whose bottom forms a small angle α with said support surface, and is flush with the outer surface of the cylindrical portion at the outer end thereof.

17. The installation according to claim 16, wherein the dripper feed station includes a guide support engaged in said inner mandrel as far as the height of said support surface, the surface located opposite said support surface forming said counter-support surface and wherein the top face of said guide support is substantially parallel to the bottom of said groove, over at least one portion located opposite the latter.

18. The installation according to claim 15, wherein the top face of said guide support forms a guide rail.

19. The installation for manufacturing a drip irrigation pipe provided with drippers, including a dripper feed station, followed by an extrusion station, including an extrusion head producing a tubular blank, means for calibrating said tubular blank and means for welding the drippers to the inner wall of said blank, wherein the dripper welding means include a support surface located opposite said tubular blank at a distance selected such that the drippers are pressed between said support surface and said tubular blank in order to be welded thereto, said support surface being arranged upstream of the calibrating means.

20. The installation according to claim 19, wherein said dripper feed station is arranged to convey said drippers over said support surface.

21. The installation according to claim 19, wherein said support surface is arranged in immediate proximity to the extrusion head.

22. The installation according to claim 21, wherein said extrusion head includes a die formed of an outer mandrel and an inner mandrel arranged together to define an extrusion channel wherein said tubular blank is formed, and wherein the dripper feed station includes a guide support engaged in said inner mandrel as far as the height of said tubular blank, the surface located opposite said tubular blank forming said support surface.

23. The installation according to claim 22, wherein said inner mandrel and said outer mandrel each include a cylindrical portion respectively engaged in one another so as to define at least in part said extrusion channel, the wall of the cylindrical portion of the inner mandrel being thinned in proximity to the exit of the extrusion channel.

24. The installation according to claim 23, wherein the wall of the cylindrical portion of the inner mandrel has a thickness comprised between 0.1 mm and 1 mm in proximity to the exit of the extrusion channel.

25. The installation according to claim 23, wherein the inner surface of the cylindrical portion forms a small angle α with said support surface.

26. The installation according to claim 12, wherein the inner surface of the cylindrical portion forms a small angle α with said support surface.

27. The installation according to claim 20, wherein said support surface is arranged in immediate proximity to the extrusion head.