KR20090077461A - Manufacturing method of fuel hose for vehicle - Google Patents

Abstract

A manufacturing method of a fuel hose for a vehicle is provided to offer strong adhesive force with resistant transparency by performing an extrusion process and a negative pressure process in a forming process of an intermediate layer of a fluorine resin layer in an internal layer consisting of a fluorine rubber tube. A manufacturing method of a fuel hose for a vehicle includes the following steps of: forming an internal layer(10) of a tube shape by extruding fluorine rubber to a rubber extruder; applying the fluorine rubber on the surface of the internal layer; forming an intermediate layer on the surface of the internal layer by extruding the fluorine rubber in negative pressure of -0.21 ~ -0.49Mpa; heating the internal layer and an intermediate layer(12) with a heating unit; forming an outer layer(14) on the surface of the intermediate layer by extruding epichlorohydrin rubber; and cooling the interlayer, the intermediate layer, and an outer layer which are combined.

Description

Manufacturing method of fuel hose for vehicle {Manufacturing method of fuel hose for vehicle}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a fuel hose for an automobile. Specifically, an automobile having improved durability by enhancing adhesion of components constituting each layer of a fuel hose having a property of preventing fuel from penetrating the fuel hose. It relates to a method for producing a fuel hose.

Generally, a fuel supply device for an automobile is a device for supplying a suitable mixer required by an engine, a fuel tank for storing fuel, a fuel filter for removing impurities in fuel, and a fuel pipe or fuel connecting the fuel device components. It consists of a hose.

In general, the fuel supply line and the return line, which are close to the engine, use a fuel hose that can be flexibly formed to prevent damage due to vibrations while driving the engine and to minimize interference due to a complicated structure around the engine.

Commonly used fuel hoses are FKM (Fluoro Rubber, Fluoro Carbon Monomer) hoses, which do not meet the fuel permeability zero required by the new regulations on North American export vehicles.

Looking at the changes in the regulations, the existing fuel hose was subjected to the hot soak test and the dialural test, the amount of fuel transmitted from the fuel hose had to satisfy the 2.0g / test or less, but the new law In the above, the hot soak test and the radial test were conducted, and the amount of fuel transmitted from the fuel hose was required to be 0.00 g / test or less.

The hot soak test is a test for measuring how much fuel is discharged to the outside by heating a single product, and the radial test is a whole device (fuel tank to engine) after connecting the fuel system of the vehicle. ) Is a test that measures the degree of internal fuel leakage when the engine is operated by increasing the temperature by putting it in a sealed place.

In order to satisfy the fuel permeability zero as a result of the test as described above, Korean Patent Laid-Open Publication No. 2003-0023327 discloses a technique in which the outside of the FKM hose is coated with fluorine resin. By coating the outside of the FKM hose with the fluorine resin as described above, the amount of fuel passing through the fuel hose can be zero, but the adhesion between the fluorine rubber layer and the fluorine resin layer constituting the fuel hose is reduced, thereby reducing the amount of fuel. The problem of poor adhesion occurs when forming the hose is an urgent need for improvement.

The problem to be solved by the present invention is to improve the adhesive force between the layers constituting the fuel hose of the fuel hose that can achieve zero fuel permeability without the poor adhesion of the fuel hose in the molding process such as bending It is to provide a manufacturing method.

In order to achieve the above object, the present invention,

Extruding the fluorine rubber with a rubber extruder to form a tube-shaped inner layer;

Coating a fluororesin on the surface of the inner layer;

Extruding the fluorine resin with an extruder under a negative pressure of -0.21 to -0.49 Mpa to form an intermediate layer on the surface of the inner layer;

Heating the integrated inner layer and the intermediate layer by heating means; And

Extruding epichlorohydrin rubber on the surface of the intermediate layer to form an outer layer; And cooling the coalesced inner layer, the middle layer and the outer layer.

According to one embodiment of the invention, the fluorine rubber is FKM, the fluorine resin is THV.

According to one embodiment of the invention, the thickness of the inner layer is 1 to 2.5mm, the thickness of the intermediate layer is 0.2 to 1mm, the thickness of the outer layer is 1.5 to 3mm.

Hereinafter, the embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a perspective view showing a fuel hose for a vehicle according to the present invention, Figure 2 is a cross-sectional view.

The fuel hose 100 is composed of three layers, an inner layer 10, an intermediate layer 12, and an outer layer 14. A tubular fluorine rubber is applied to the inner layer 10, and the fluorine resin is applied to the intermediate layer 12. Is applied, epichlorohydrin is applied to the outer layer (16), forming a structure integrated with each other. By forming such a three-layer structure, it is possible to make the content of the fuel penetrating the fuel hose be 0.00 g / test or less when measured by the hot soak test and the dialect test. Become.

The fuel hose 10 of the present invention is manufactured by an extrusion process by an extruder, the inner layer 12, the intermediate layer 14 and the outer layer 16 are integrally manufactured by combining with each other, at a predetermined pressure in the process of forming the intermediate layer By negative pressure, the adhesion between the inner layer 12 and the intermediate layer 14 is strengthened so that the adhesive portion does not come off during molding such as bending, thereby strengthening the durability, and in the harsh conditions such as high temperature and high humidity applied to the automotive engine room. It is possible to prevent each component layer constituting the fuel hose from being separated or cracked.

A method of manufacturing a fuel hose for a vehicle having such a structure will be described with reference to FIG. 3.

In order to manufacture the fuel hose of the present invention, the rubber extruder 16, the fluororesin extruder 20, the heating device 22, the eco-extruder 24, the cooling bath 26, the cutting machine 28 are In order to be arranged, in particular, the fluorine resin extruder 20 is provided with a negative pressure device 21 to apply a predetermined pressure in the fluorine resin extrusion process. A laser optical device 17 between the rubber extruder 16 and the fluororesin extruder 20, between the fluororesin extruder 20 and the heating device 22, and between the echo extruder 24 and the cooling bath 26. ) Are respectively installed to measure the rubber outer diameter of each layer. In addition, a puller 19 is provided between the cooling bath 26 and the cutter 28.

The pressure exerted by the negative pressure device 21 is preferably -0.21 to -0.49 Mpa, preferably -0.3 to -0.4 Mpa. If the pressure is less than -0.21 Mpa, the adhesive force may be lowered, and -0.49 If it exceeds Mpa, it is not preferable because wrinkles may occur in the fluororesin layer or the inner layer of the fluororesin layer.

In order to manufacture the fuel hose according to the present invention, first, the step of extruding the inner layer of the fluororubber tube using the rubber extruder 16 is performed. The fluororubber tube serves to prevent fine leakage of fuel. As a raw material used to form the fluororubber tube, fluorine rubber 15 is used, and the fluorine rubber 15 preferably has a fluorine content of 60 to 75% by weight. For example, FKM (Fluoro Rubber, Fluoro Carbon Monomer) is more preferable. If the content of fluorine is less than 60% by weight, the resistance to fuel oil is weakened. On the contrary, if the content of fluorine is 75% by weight or more, cold resistance may be lowered, which is not preferable.

It is preferable that the fluororubber tube has a thickness of 1 to 2.5 mm, and if the thickness is less than 1 mm, it is difficult to extrude the tube.

Next, the fluororesin is melt-extruded on the surface of the fluororubber tube obtained by passing through the inner rubber extruder 16 to coat the fluororesin. The fluorine resin coated in this way is to improve the binding force between the inner layer and the intermediate layer.

Subsequently, when the fluororubber tube passes through the fluororesin extruder 20, the fluororesin 13 is extruded and integrated on the surface of the FKM tube to form an intermediate layer. The intermediate layer serves to suppress the penetration of fuel gas generated through the cross section of the hose.

As described above, the extrusion of the intermediate layer is performed under the negative pressure by the negative pressure device 21 as described above, and the extrusion process is performed together with the negative pressure process to more strongly adhere the fluororesin layer forming the intermediate layer to the fluorine rubber tube. It is possible to be.

The negative pressure device 21 is attached to the fluorine resin extruder 20, the negative pressure is attached to the negative pressure in the reverse direction of the resin extrusion when extruded the resin serves to increase the adhesion of the fluorine resin to the fluorine rubber layer, so that the fluorine resin layer It can be more strongly adhered to the fluororubber tube.

The fluorine resin 13 constituting the intermediate layer is not particularly limited, but is preferably a Teflon (TEFLON) resin, an ethylene tetrafluoroethylene (ETFE) resin, or a THF (tetrafluoroethylene hexafluropropylene vinylidenefluoride) resin, and THV is preferable in terms of cold resistance and workability More preferred.

In addition, the thickness of the intermediate layer is preferably 0.2 to 1 mm, more preferably 0.3 to 0.5 mm. If the thickness is less than 0.2mm, the extrudability is lowered, and if the thickness is greater than 1mm, cold resistance and flexibility may decrease and wrinkles may occur, which is not preferable.

Subsequently, the fluorine resin tube constituting the inner layer 10 and the intermediate layer 12, which are integrated with each other, are heated by the heating means 22, and the echo (epchlorohydrin rubber) 23 for the inner layer, which is a post-process, is formed. Make the coating process easy. The heating temperature by the heating means is preferably 150 to 220 ℃, if the heating temperature is less than 150 ℃ the degree of plasticization of the fluorine rubber and fluorine resin has a problem that the adhesion is lowered, if it exceeds 220 ℃ and fluorine rubber and It is not preferable because the fluororesin does not endure high heat and deteriorates workability.

Next, the fluororesin of the intermediate layer 12 is extruded into the fluororubber tube of the inner layer 10, and then, in the heated state, is made to pass through the eco-extruder 24 so that the surface of the intermediate layer 12 is epichlorohexyl. Since the outer layer 14 made of Drain (eco) is integrally formed by extrusion, the fluororubber tube of the inner layer 10, the fluorine resin of the intermediate layer 12, and the echo of the outer layer 14 are integrated together. Structure is produced.

The outer layer 14 serves to inhibit the hose outer surface from being damaged or deteriorated by active oxygen or ozone in the air, and the outer layer 14 may have a thickness of 1.5 to 3 mm. If the thickness of the outer layer 14 is less than 1.5 mm, the protection function of the fuel hose may be lowered and durability may be lowered. If the thickness of the outer layer 14 is greater than 3 mm, the flexibility may be lowered.

Finally, the structure in which the inner layer 10, the intermediate layer 12, and the outer layer 14 are combined is cooled by passing through the cooling bath 26, and then tensioned by the puller 19, and then the cutter 28 is removed. By cutting to a predetermined size through the desired fuel hose 100 is completed.

In the method of manufacturing a fuel hose for automobiles according to the present invention, in forming the intermediate layer of the fluorine resin layer on the inner layer of the fluorine rubber tube, by performing a negative pressure process together with the extrusion process, it is possible to impart strong adhesion while satisfying fuel permeability. It becomes possible. As a result, adhesion failure does not occur, thereby increasing the reliability of the product and improving durability.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.

Example 1

The fuel hose was manufactured using the apparatus shown in FIG.

First, the FKM tube 10 forming the inner layer was extruded to a thickness of 1.5 mm using the rubber extruder 16, and then fluororesin was melt-coated on the surface. Subsequently, the negative pressure device 21 was used to pass the FKM tube 10 through a fluororesin (THV) extruder 20 under a negative pressure of -0.3 MPa to form a THV layer 12 as an intermediate layer with a thickness of 0.3 mm. Next, the FKM tube 10 and the THV layer 12 integrated with each other are heated to 180 ° C. by the heating means 22, and then passed through the eco-extruder 24 to the surface of the THV layer 12. The outer layer 14 of epichlorohydrin was extruded to a thickness of 2.5 mm to be integrally molded. Finally, after cooling them by passing through the cooling bath 26, the target fuel hose 100 was manufactured by cutting to a predetermined size with a cutter (28).

Example 2

A fuel hose 100 was manufactured in the same manner as in Example 1, except that the negative pressure applied during extrusion of the intermediate layer 12 was changed to −0.4 Mpa.

Comparative Example 1

A fuel hose 100 was manufactured in the same manner as in Example 1, except that the negative pressure applied when the intermediate layer 12 was extruded in Example 1 was changed to −0.2 Mpa.

Comparative Example 2

A fuel hose 100 was manufactured in the same manner as in Example 1 except that the pressure applied during extrusion of the intermediate layer 12 was changed to −0.5 Mpa.

Test Example 1: Adhesion Test

In the fuel hoses obtained in Examples 1 and 2, no decrease in adhesive force occurred, and no wrinkles were observed. In the case of Comparative Example 1, the FKM layer and the THV layer was not partially bonded, it was confirmed that it is separated by about 10mm when visually confirmed, in the case of Comparative Example 2 was good adhesion, but it was confirmed that wrinkles due to excessive pressure It was.

Test Example 2 Fuel Permeation and SHED Evaluation

As a result of measuring the fuel permeation rate of the fuel hose 100 obtained in Example 1 and Comparative Example 1, the fuel hose obtained in Example 1 was 2g / m ² -day, the fuel hose obtained in Comparative Example 1 was 16g / m ² -day. In addition, according to the SHED (Sealed Housing for Evaporative Determination) evaluation, the fuel hose obtained in Example 1 was 0.00g / test, the fuel hose obtained in Comparative Example 1 was 0.02g / test. Therefore, it can be seen that the fuel hose obtained in Example 1 has better fuel permeability.

1 is a perspective view showing a fuel hose for a vehicle according to the present invention,

2 is a cross-sectional view showing a fuel hose for an automobile according to the present invention;

3 is a schematic view showing a method of manufacturing a fuel hose for an automobile according to the present invention.

<Explanation of symbols for the main parts of the drawings>

10: inner layer 12: middle layer

14 outer layer 16: fluororubber extruder

20: fluororesin extruder 21: negative pressure device

22: heating device 24: eco-extruder

26: cooling bath 100: fuel hose

Claims (3)

Extruding the fluorine rubber with a rubber extruder to form a tube-shaped inner layer; Coating a surface of the inner layer with a fluorocarbon resin Extruding the fluorine resin with an extruder under a negative pressure of -0.21 to -0.49 Mpa to form an intermediate layer on the surface of the inner layer; Heating the integrated inner layer and the intermediate layer by heating means; Extruding epichlorohydrin rubber on the surface of the intermediate layer to form an outer layer; And Cooling the coalesced inner layer, intermediate layer and outer layer; manufacturing method of a fuel hose comprising a. The method of claim 1, The fluorine rubber is FKM, the fluorine resin is THV manufacturing method of the fuel hose. The method of claim 1, The thickness of the inner layer is 1 to 2.5mm, the thickness of the intermediate layer is 0.2 to 1mm, the thickness of the outer layer is 1.5 to 3mm manufacturing method of the fuel hose.

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