WO2013157296A1

WO2013157296A1 - Fastening structure for supercharger system pipe

Info

Publication number: WO2013157296A1
Application number: PCT/JP2013/054090
Authority: WO
Inventors: 光泰川原; 熊谷　宏; 理恵藤満; 智彦齊藤
Original assignee: 日産自動車株式会社
Priority date: 2012-04-17
Filing date: 2013-02-20
Publication date: 2013-10-24
Also published as: JP2013221580A

Abstract

A fastening structure for a pipe used between system component devices such as a turbocharger, an intercooler, and a pipe joint which constitute a supercharger system, the fastening structure for a supercharger system pipe being configured having a structure in which a turbo hose (H) is fitted by a clamp (C) or a quick connector to a bulged pipe connecting part (P) of a system component device (M), the turbo hose (H) being provided with an innermost layer (1) comprising a fluorine-compound-based rubber, and an outer cover layer (2) on the outside thereof, and the rupture elongation of the innermost layer (1) being at least 100% in an environment of 230°C or lower. By this configuration, cracking of the innermost layer (1) due to misalignment of the pipe connecting part (P) and the turbo hose (H) is prevented.

Description

Fastening structure for turbocharger system piping

This invention relates to the fastening structure of the piping for supercharger systems used for connecting between the apparatuses which comprise a supercharger system.

Conventionally, as a pipe used for a supercharger system, there is a heat-resistant hose (turbo hose) described in Patent Document 1. The heat-resistant hose of Patent Document 1 includes a first inner rubber layer, a second inner rubber layer, a reinforcing yarn layer, and an outer rubber layer from the inside. The first inner rubber layer is made of a fluorine compound rubber. The second inner rubber layer and the outer rubber layer are made of silicone rubber. Further, the reinforcing yarn layer is formed of reinforcing yarn such as aramid resin. The heat-resistant hose has improved fatigue resistance by defining the properties of the silicone rubber that forms the second inner rubber layer and the outer rubber layer and the number of reinforcement yarns that are driven into the reinforcement yarn layer.

Japanese Unexamined Patent Publication No. 2008-248943

By the way, in the pipe fastening structure used in the supercharger system, the turbo hose is fitted to a pipe connecting part with a bulge in devices such as a supercharger, an intercooler, and a pipe joint. It is common to fasten with a connector. In such a fastening structure, when the pulsation due to gas pressure or vibration of the engine is received, there is a possibility that a deviation in the separating direction may occur between the pipe connecting portion and the turbo hose. Is used for the turbo hose, there is a possibility that a large strain is generated in the innermost layer of the turbo hose between the bulge and the end of the clamp, and the innermost layer is cracked.

The present invention was made in view of the above-described conventional situation, and is a structure that fastens a turbo hose using a clamp or a quick connector to a pipe connecting portion with a bulge constituting a supercharger system, It aims at providing the fastening structure of the piping for supercharger systems which can prevent the crack generation of the innermost layer resulting from the shift | offset | difference of a piping connection part and a turbo hose.

The present invention relates to a fastening structure for piping used between system components such as a turbocharger, an intercooler, and a pipe joint constituting a supercharger system, and a clamp or a quick connector is connected to a pipe connecting portion with a bulge of the system components. It has a structure in which a turbo hose is fitted. In the supercharger system piping fastening structure, the turbo hose has an innermost layer made of fluorine compound rubber and an outer skin layer on the outer side, and the innermost layer has a breaking elongation of 230 ° C. Therefore, the above configuration is used as a means for solving the conventional problems.

According to the fastening structure for a supercharger system pipe according to the present invention, in a structure in which a turbo hose is fastened using a clamp to a bulge-attached pipe connecting part of a device constituting the supercharger system, the pipe connecting part and the turbo Generation of cracks in the innermost layer due to deviation from the hose can be prevented.

It is sectional drawing explaining one Embodiment of the fastening structure of the piping for supercharger systems which concerns on this invention. It is sectional drawing orthogonal to the axis line of the turbo hose shown in FIG. It is sectional drawing which follows the axis line of the turbo hose shown in FIG.

Hereinafter, an embodiment of a fastening structure for a supercharger system pipe according to the present invention will be described based on the drawings.
The fastening structure shown in FIG. 1 is such that a turbo hose H is fitted to a pipe connecting part P with a bulge (B) of the equipment M constituting the supercharger system, and a clamp C is fixed to the outer periphery of the fitting part. It consists of.

The equipment M constituting the supercharger system includes a turbocharger, an intercooler, a pipe joint, and the like. The bulge B is a bulging portion for retaining the cap integrally formed at the tip of the pipe connecting portion P or the like. The clamp C is a well-known piping clamp having a band portion and a connecting portion, and the turbo hose H is fastened to the piping connecting portion P at a position closer to the base end side than the bulge B. A quick connector may be used instead of the clamp.

2 and 3, the turbo hose H has an innermost layer 1 made of a fluorine compound rubber and an outer skin layer 2 outside thereof. The outer skin layer 2 has a reinforcing yarn layer 3 between the layers, and the inner side of the reinforcing yarn layer 3 is an intermediate layer 2A and the outer side of the reinforcing yarn layer 3 is an outermost layer 2B.

In the turbo hose H, the breaking elongation of the innermost layer 1 is 100% or more in an environment of 230 ° C., and the compressibility of the innermost layer 1 in a state where the turbo hose is fastened is in a range of 20 to 50%. It is supposed to be.

In the fastening structure with the above configuration, when subjected to pulsation due to gas pressure or vibration of the engine, it is further promoted by oil adhering to the surface of the fastening part pipe, and is separated between the pipe connection part P and the turbo hose H. In FIG. 1, the turbo hose H is strongly sandwiched between the apex of the bulge B and the end of the clamp C (right end) in FIG.

Here, when the deviation in the separating direction as described above occurs, the distance between the apex of the bulge B and the end of the clamp C becomes small. At this time, when the strain generated in the innermost layer 1 of the turbo hose H was measured with a microscope, it was found that about 70% strain was generated in the innermost layer 1. Thus, when a large strain occurs in the innermost layer 1 between the bulge B and the end of the clamp C, there is a possibility that the innermost layer 1 will crack.

On the other hand, in the above fastening structure, the breaking elongation of the innermost layer 1 is 100% or more in an environment of 230 ° C., so that the pipe connecting portion P and the turbo hose H It is possible to prevent the innermost layer 1 from cracking due to the deviation.

In addition, the breaking elongation of the innermost layer 1 in a turbo hose fastening state is 100% or more under an environment of 230 ° C. This is because the distortion generated in the innermost layer 1 of the turbo hose H is due to the following two factors.
1. In an initial state in which the turbo hose H is fastened with the clamp C, the innermost layer 1 has a compression rate of 20% to 50%, that is, 20% to 50%.
2. Oil accumulation on the pipe surface, rocking of the turbo hose H (swing amount: minimum ± 5 mm to maximum ± 40 mm), and repeated supercharging (minimum: 0.1 MPa to maximum 0.4 MPa) Deviation occurs from the fastened state, and is sandwiched between the bulge B and the end of the clamp C of the pipe connecting portion P. As a result, the force that causes the turbo hose H to come off due to supercharging and swinging concentrates between the back angle of the bulge B and the end of the clamp, so that the turbo hose H is further compressed and deformed. Will occur.

The initial compression rate of the innermost layer 1 when the turbo hose is fastened is set to 20 to 50%, so that hose disconnection and air leakage during supercharging can be suppressed. If the initial compression ratio exceeds 50%, the clamp may be damaged. Therefore, by setting the compressibility of the innermost layer 1 in the range of 20 to 50%, it is possible to reliably prevent the innermost layer 1 from cracking.

Further, in the fastening structure of the present invention, as a more desirable embodiment, the fluorine compound rubber forming the innermost layer 1 is a peroxide vulcanization system and has a Shore hardness of 65 to 80, and MEK (methyl ethyl ketone) It is assumed that the volume swelling ratio when immersed in the container at 40 ° C. for 70 hours is in the range of 400 to 700%. Fluorine compound rubber forming the innermost layer 1 is binary (copolymer of vinylidene fluoride and hexafluoropropylene), ternary (terpolymer of vinylidene fluoride, hexafluoropropylene and tetrafluoroethylene), and tetrafluoro. Any of the copolymers of ethylene and propylene can be used as the polymer.

In the fastening structure having the above-described configuration, the innermost layer 1 is formed of a peroxide vulcanized fluorine compound rubber, so that high resistance to acids generated in the piping environment of the intercooler can be obtained. The fluorine compound rubber forming the innermost layer 1 has a Shore hardness in the range of 65 to 80, so that both supercharging and prevention of hose disconnection due to rocking, air sealability, and workability during pipe insertion are achieved. It becomes possible to do.

In addition, by setting the MEK volume swelling ratio of the innermost layer 1 to 400% to 700%, it becomes possible to achieve both high elongation characteristics and rubber strength of fluororubber. Therefore, by setting the Shore hardness of the fluorine compound rubber to 65 to 80 and the MEK volume swelling ratio to be in the range of 400 to 700%, the functions of the turbo hose H such as prevention of hose disconnection and air sealability described above can be achieved. A good balance between elongation characteristics and strength can be obtained.

Further, in the fastening structure of the present invention, as a more desirable embodiment, the outer skin layer 2 is made of silicone rubber, acrylic rubber, ethylene / acrylic rubber, ethylene / propylene rubber, chloroprene, chlorosulfonated rubber, epichlorohydrin rubber and hydrogenated nitrile rubber. One of these is used as a material.

According to the fastening structure having the above configuration, it is more desirable to use any of silicone rubber, acrylic rubber, and ethylene / acrylic rubber from the viewpoint of heat resistance.

Furthermore, the fastening structure of the present invention relates to a reinforcing yarn layer 3 disposed between the outer layers 2 of the turbo hose as a more preferable embodiment, and has a thickness ta of the innermost layer 1 and an innermost layer as shown in FIG. It arrange | positions so that the relationship with thickness tb from 1 to the reinforcement thread | yarn layer 3 may be set to 0.5 mm <ta <tb <3mm.

In the fastening structure of the present invention, by setting the thickness ta of the innermost layer 1 to 0.5 mm or more, it is possible to suppress excessive distortion from occurring in the innermost layer 1 due to hose displacement at the time of supercharging and swinging, and further reinforcement It is possible to suppress the possibility that the yarn layer is exposed to the innermost layer. Further, by setting the thickness tb from the innermost layer 1 to the reinforcing yarn layer 3 to 3 mm or less, the reinforcing yarn layer 3 suppresses deformation of the innermost layer 1 at the time of supercharging. Excessive distortion can be suppressed. Therefore, by setting the relationship between the thickness ta of the innermost layer 1 and the thickness tb from the innermost layer 1 to the reinforcing yarn layer 3 as described above, the amount of strain generated in the innermost layer 1 when the hose is displaced can be suppressed. Can do.

Further, in the fastening structure of the present invention, as a more desirable embodiment, the compression elastic modulus Ea of the rubber forming the innermost layer 1 is more than the compression elastic modulus Eb of the rubber of the intermediate layer 2A and the outermost layer 2B constituting the outer skin layer 2. (Ea> Eb), the compression elastic modulus Ea of the rubber of the innermost layer 1 is in the range of 10 to 25 MPa under an environment of 230 ° C., and the compression elastic modulus Eb of the rubber of the intermediate layer 2A and the outermost layer 2B is It is assumed that the pressure is 2 to 9 MPa in an environment of 230 ° C.

In the fastening structure of the present invention, by setting the compression elastic modulus Ea of the rubber of the innermost layer 1 to 10 MPa or more even at 230 degrees, it is possible to maintain sufficient rubber strength so as not to show significant deformation even when a hose shift occurs. In addition, by setting the pressure to 25 MPa or less even at 230 ° C., the turbo hose H can be inserted into the pipe connection portion P without any problem. Further, if the compression elastic modulus of the rubber of the intermediate layer 2A and the outermost layer 2B is 2 to 9 MPa, the rubber is sufficiently compressed at the time of clamping, so that sufficient sealing performance can be secured.

Furthermore, in the fastening structure of the present invention, as a more desirable embodiment, the reinforcing yarn forming the reinforcing yarn layer 3 is mixed into a long fiber or material formed in one of spiral winding, braid knitting and knitting winding. It is assumed that it is a short fiber. Thereby, the intensity | strength of the outer skin layer 2 and the turbo hose H whole becomes a higher thing.

Example 1
[Hose production]
In producing the hose having the structure shown in FIG. 2, a ternary FKM (a terpolymer of vinylidene fluoride, hexafluoropropylene, and tetrafluoroethylene) that forms the innermost layer 1 according to the formulation shown in Table 1 was used. Further, silicon rubber was used for the intermediate layer (2A) and the outermost layer (2B), and polymetaphenylene terephthalamide was used for the reinforcing yarn layer (3).

Next, each material was prepared, and each material was kneaded using a kneader, and then a rubber composition was prepared by adding a crosslinking agent and a co-crosslinking agent and kneading using a roll.

Next, a hose (turbo hose H) was created using the rubber composition.
In the first step, the innermost layer 1 was extruded on a mandrel with a specified thickness.
In the second step, the intermediate layer 2A was extruded on the outer peripheral surface of the innermost layer 1 with a specified thickness.
In the third step, polymetaphenylene terephthalamide fibers were knitted on the outer periphery of the laminate by knitting winding to form a reinforcing yarn layer.
In the fourth step, the outermost layer 2B was extruded and formed with a specified thickness on the outer periphery of the laminate.
Each layer was molded into a mandrel as described above, and then primary vulcanized at 165 ° C. and secondary vulcanized at 185 ° C.
The thickness of each layer of the hose is 0.7 mm for the innermost layer (FKM layer), 1.8 mm for the intermediate layer, and 2.5 mm (outermost layer) for the outermost layer. The outer diameter of the hose is 63.2 mm, and the length of the hose is 300 mm.

In evaluating the material of the fluoro rubber, only the fluoro rubber layer was sliced from the hose into a sheet shape, and the following physical properties were evaluated.
[Tensile properties]
Regarding the elongation at break of rubber, a tensile test was carried out with a dumbbell test piece in a constant temperature layer at 230 ° C., and the tensile strength and the elongation at break were measured.
[Volume swelling]
A fluororubber of 10 mm × 10 mm × 0.5 mm was immersed in MEK (methyl ethyl ketone) at 40 ° C. for 70 hours, and the volume change rate thereafter was measured with a hydrometer.
[Compressive modulus]
Regarding the compression modulus of rubber, the modulus of elasticity until 25% compression of a test piece (diameter: 29 mm, thickness: 12.5 mm) of fluororubber and silicon rubber was measured at room temperature.

[Hose repeated pressure durability evaluation]
One end of the hose of Example 1 prepared as described above is fitted into an aluminum pipe with a bulge whose surface is thinly coated with silicone oil, and a clamp is fastened to the fitting portion at 7 Nm, and the other end of the hose The part was closed with a blind plug and the aluminum pipe was connected to a nitrogen cylinder. This was left in a thermostatic bath at 230 ° C. for 30 minutes and then pressurized to 0.3 MPa.
As a result, the hose slipped from the pipe and the hose was sandwiched between the clamp and the bulge. This pressure cycle (0 to 0.3 MPa) was performed 100 times, and then the presence or absence of cracks in the inner surface layer of the hose was confirmed. In the hose of Example 1, it was confirmed that cracks were not generated on the inner surface of the fluororubber layer and that it had sufficient strength and elongation.

(Example 2)
Except that the blending amount of the vulcanization accelerator in the fluororubber was 0.9 phr, the same hose as in Example 1 was produced and the same test was performed.

(Comparative Example 1)
A hose similar to that of Example 1 was prepared and the same test was performed except that the blending amounts of carbon black (CB), crosslinking agent, and vulcanization accelerator in the fluororubber were changed.

The above Examples 1 and 2 and Comparative Examples are shown in Table 1 below.

As is clear from Table 1, in Comparative Example 1, a crack was generated in the innermost layer 1 due to a shift between the pipe connecting portion and the turbo hose. On the other hand, in Examples 1 and 2, it was confirmed that the innermost layer 1 was not cracked and had sufficient strength and sufficient sealability.

The fastening structure of the supercharger system pipe of the present invention is not limited to the above-described embodiment, and the details of the structure can be appropriately changed without departing from the gist of the present invention. .

B Bulge C Clamp H Turbo hose P Pipe connection M Equipment 1 Innermost layer 2 Outer skin layer

2A Middle layer

2B Outermost layer 3 Reinforcement yarn layer

Claims

A fastening structure for piping used between system components such as a turbocharger, an intercooler and a pipe joint constituting the turbocharger system,
It has a structure in which a turbo hose is fitted with a clamp or quick connector to the pipe connection part with bulge of the system component equipment,
The turbo hose has an innermost layer made of fluorine compound rubber and an outer skin layer on the outer layer,
A fastening structure for piping for a supercharger system, wherein the breaking elongation of the innermost layer is 100% or more under an environment of 230 ° C.
2. The supercharger system pipe fastening structure according to claim 1, wherein an initial compression ratio of the innermost layer of the turbo hose is in a range of 20 to 50%.
The fluorine compound rubber forming the innermost layer is a peroxide vulcanization system, and has a Shore hardness of 65 to 80 and a MEK volume swelling ratio in the range of 400 to 700%. The fastening structure of the piping for supercharger systems of 1 or 2.
The outer skin layer has a reinforcing yarn layer between the layers,
The relationship between the thickness ta of the innermost layer and the thickness tb from the innermost layer to the reinforcing yarn layer is arranged such that 0.5 mm <ta <tb <3 mm. The fastening structure of the piping for supercharger systems of any one of these.
The compression elastic modulus Ea of the rubber forming the innermost layer is larger than the compression elastic modulus Eb of the rubber forming the outer skin layer, and the compression elastic modulus Ea of the rubber of the innermost layer is in the range of 10 to 25 MPa under an environment of 230 ° C. The supercharger system according to any one of claims 1 to 4, wherein the compression elastic modulus Eb of the rubber of the outer skin layer is in a range of 2 to 9 MPa under an environment of 230 ° C. Fastening structure for piping.
The outer skin layer is made of any one of silicone rubber, acrylic rubber, ethylene / acrylic rubber, ethylene / propylene rubber, chloroprene, chlorosulfonated rubber, epichlorohydrin rubber, and hydrogenated nitrile rubber. 6. A fastening structure for a supercharger system pipe according to any one of 1 to 5.
The reinforcing yarn forming the reinforcing yarn layer is a long fiber formed in any one of spiral winding, braided knitting and knitting winding, or a short fiber mixed in a material. Fastening structure for the turbocharger system described.