Internal tube for tanks, particularly fuel tanks of automobiles

Abstract

An internal tube for tanks, particularly fuel tanks of automobiles, wherein the tube has a fluid channel and a tube wall that encloses the fluid channel, wherein the tube wall has a multilayer design and is composed of at least three layers, with one inner layer based on at least one polyolefin being provided, with at least one central layer based on at least one polyamide being present, and with one outer layer based on at least one polyolefin being provided.

Claims

1. An internal tube for tanks, wherein the tube has a fluid channel and a tube wall that encloses the fluid channel, wherein the tube wall has a multilayer design and is composed of at least three layers, including an inner layer formed from at least one polyolefin, at least one central layer formed from at least one polyamide, and an outer layer formed from at least one polyolefin; wherein the inner layer and the outer layer have a smaller layer thickness than the at least one central layer.

2. The internal tube for tanks as set forth in claim 1, wherein first and second adhesion promoter layers are arranged between the inner layer and the central layer, and between the outer layer and the central layer, respectively.

3. The internal tube for tanks as set forth in claim 1, wherein the inner layer is electrically conductive.

4. The internal tube for tanks as set forth in claim 1, wherein the inner layer is formed from high-density polyethylene (HDPE).

5. The internal tube for tanks as set forth in claim 1, wherein the layer thickness of the inner layer is 0.01 to 0.4 mm.

6. The internal tube for tanks as set forth claim 1, wherein the inner layer is composed of at least 80 wt % of at least one polyolefin.

7. The internal tube for tanks as set forth in claim 1, wherein the inner layer is in direct contact with a fluid that is conducted in the fluid channel.

8. The internal tube for tanks as set forth in claim 1, wherein the at least one central layer is made on the basis of at least one polyamide from the group polyamide 6, polyamide 6.6, polyamide 12, polyamide 612, polyphthalamide.

9. The internal tube for tanks as set forth in claim 1, wherein the layer thickness of the at least one central layer is 0.01 to 2.5 mm.

10. The internal tube for tanks as set forth in claim 1, wherein the central layer is composed of at least 80 wt % of at least one polyamide.

11. The internal tube for tanks as set forth in claim 1, wherein the at least one central layer is made on the basis of a mixture of at least one aliphatic polyamide and at least one partially aromatic polyamide or polyphthalamide.

12. The internal tube for tanks as set forth in claim 1, wherein the at least one central layer is made on the basis of at least one copolymer, with the copolymer being made on the basis of at least one aliphatic polyamide with at least one partially aromatic polyamide or polyphthalamide.

13. The internal tube for tanks as set forth in claim 1, wherein the outer layer is made on the basis of high-density polyethylene (HDPE).

14. The internal tube for tanks as set forth in claim 1, wherein the layer thickness of the outer layer is 0.01 to 0.4 mm.

15. The internal tube for tanks as set forth in claim 1, wherein the outer layer is composed of at least 80 wt % of at least one polyolefin.

16. The internal tube for tanks as set forth in claim 1, wherein the outer layer is in direct contact with a fluid that is located in the tank.

17. The internal tube for tanks as set forth in claim 1, wherein the inner layer and the outer layer are made on the basis of a mixture of polyolefins.

18. The internal tube for tanks as set forth in claim 1, wherein the total thickness (d) of the tube wall is 0.1 to 3.0 mm.

19. The internal tube for tanks as set forth in claim 1, wherein the tube is at least partially formed as a corrugated tube.

20. A fuel tank for automobiles, with at least one internal tube for tanks as set forth in claim 1, positioned on the interior of the tank.

21. An internal tube for tanks as in claim 1, wherein the inner layer is formed of polyethylene.

22. An internal tube for tanks as in claim 1, wherein the at least one central layer is formed of one of aliphatic polyamide and partially aliphatic polyamide.

23. An internal tube for tanks as in claim 1, wherein the outer layer is formed of polyethylene.

24. An internal tube for tanks as in claim 16, wherein the tank is a fuel tank and the fluid is a fuel located within the tank.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The present disclosure is explained in further detail below with reference to a schematic drawing, which illustrates only one exemplary embodiment.

(2) FIG. 1 shows a section through a fuel tank of an automobile with an internal tube according to the present disclosure for tanks, and

(3) FIG. 2 shows a perspective view of the internal tube according to the present disclosure for tanks.

DETAILED DESCRIPTION

(4) The figures show an internal tube 1 according to the present disclosure for tanks, which, like in the exemplary embodiment, is preferably arranged in a fuel tank 2 of an automobile. In principle, different types of fuel such as gasoline or diesel fuel can be present in the fuel tank 2 in which the internal tube 1 according to the present disclosure for tanks is arranged. The internal tube 1 for tanks has a fluid channel 3 and a tube wall 4 that surrounds the fluid channel 3. Preferably, and in the exemplary embodiment, the tube wall 4 surrounding the fluid channel 3 has five layers. Preferably, and in the exemplary embodiment, the inner layer 5 is made on the basis of high-density polyethylene (HDPE). Moreover, the inner layer 5 can have additives such as conductivity additives, stabilizing additives, or the like. Expediently, and in the exemplary embodiment, the inner layer 5 is followed by an adhesion promoter layer that improves the adhesion between the inner layer 5 and the layer following it. In the exemplary embodiment, a central layer is joined directly with the adhesion promoter layer 8, which central layer is preferably made on the basis of at least one aliphatic and/or semi-aliphatic polyamide, especially preferably, and in the exemplary embodiment, on the basis of polyamide 6. In addition, the central layer 6 can have additives such as conductivity additives, stabilizing additives, or the like. Recommendably, and in the exemplary embodiment, the inner layer 6 is followed immediately by an adhesion promoter layer 8 that improves the adhesion between the central layer 6 and the layer following it. Expediently, and in the exemplary embodiment, this adhesion promoter layer 8 is followed by the outer layer 7. Preferably, and in the exemplary embodiment, the outer layer 7 is made on the basis of high-density polyethylene (HDPE). In addition, the outer layer 7 can also have additives such as conductivity additives, stabilization additives, and the like.

(5) Preferably, and in the exemplary embodiment, both the inner layer 5 and the central layer 6 and the outer layer 7 are electrically conductive. For this purpose, the layers have suitable conductivity additives such as carbon black or the like.

(6) Expediently, and in the exemplary embodiment, the total thickness (d) of the tube wall is 0.2 to 2.5 mm. According to a recommended embodiment, and in the exemplary embodiment, the inner layer 5 and the outer layer 7 have a lesser layer thickness than the central layer 6. In the exemplary embodiment, the central layer 6 is therefore the layer with the greatest layer thickness.

(7) According to a preferred embodiment, and in the exemplary embodiment, all of the layers of the internal tube 1 for tanks or of the tube wall 4 contain no oligomers or substantially no oligomers. The internal tube for tanks is therefore preferably oligomer-free or substantially oligomer-free, as it were.