JPH08200561A - Small extention high-pressure hose - Google Patents

Abstract

PURPOSE: To provide a high-pressure hose having sufficient pressure resistance, light weight and small extension in relation to tensile load by constituting it by means of a first reinforcing layer taking the mean of the metallic wire winding angles on an inner surface rubber layer as the specified value, a second reinforcing layer taking the cross angle of cross-laminated layers as the specified value, and an outer surface rubber layer. CONSTITUTION: In a small-extending high-pressure hose 1, a first reinforcing layer 4 formed of one or more metallic wire winding layers, and formed by taking the mean value of the winding angles in relation to the axial direction 3 of the hose of the whole layer as ±52 deg. to 57 deg. is provided on the outer peripheral surface of a cylindrical inner surface rubber layer 2. A second reinforcing layer 6 formed one or more organic fiber winding layers, and formed by respectively taking the winding angles in relation to the axial direction 3 of the hose of respective layers to ±40 deg. to 50 deg. is provided on the outer peripheral surface of the first reinforcing layer 4 directly or through an intermediate rubber layer 5. Moreover, an outer surface rubber layer 7 is provided on the outer peripheral surface of this second reinforcing layer 6.

Description

Detailed Description of the Invention

[0001]

The present invention has sufficient pressure resistance,
The present invention relates to a low-elongation high-pressure hose that is lightweight and has a small elongation with respect to a tensile load.

[0002]

2. Description of the Related Art A hose has different performance required depending on its use, but is long, for example, by a ground improvement method or the like, for example, a high pressure having a length of about 30 to 60 meters (m). For example, if you use a hose or deeper, the length is 20
m hoses are connected and a fluid material with a high specific gravity for ground improvement is pumped and injected into a hole drilled from the surface of the earth, or a long distance from a high position such as a crane. For applications such as civil engineering and construction work in which a high-pressure hose with a length of about 20 to 60 m is suspended and pumped and infused with cement milk or the like from the ground, in addition to pressure resistance, especially tensile load is applied.
It is necessary to have a property that the amount of expansion and contraction when unloading is small. Because the high-pressure hose is used in a long size, the hose itself has its own weight, the weight of a fluid material having a high specific gravity to be pumped and injected, and parts such as a nozzle attached to the tip of the hose. This is because a large tensile load is applied to the hose due to the weight of 1. However, if the amount of expansion and contraction of the high-pressure hose is large when the tensile load is loaded or unloaded, it becomes very difficult to handle. Further, when the positioning of the tip of the hose is required, the work is extremely difficult due to the large expansion and contraction amount.

In addition, since the high-pressure hose, which easily expands during use, is difficult to handle, a part of the hose tends to be caught in an unintended place due to some trouble. At this time, a tensile load acts and The hose may become longer and the positioning work may become more difficult, and if the hooked part comes off, the hose jumps in an unexpected direction due to the recoil due to the large expansion and contraction amount. As a result, it was extremely dangerous if there were people or dangerous materials nearby. Further, the stretchable high-pressure hose is liable to be rubbed against the other equipment, the wall surface of the excavation hole, or damaged, or the other equipment.

Therefore, the conventional low elongation high pressure hose is
As a reinforcing layer, a metal wire having low extensibility is used, and as a first metal wire reinforcing layer consisting of one layer on the outer circumference of the inner rubber layer, the theoretical static angle ± 5 with respect to the axial direction of the hose.
Braided at about 4.7 degrees, and the second metal wire reinforcement layer of the second layer is ±± with respect to the axial direction of the hose on the outer peripheral surface of the first metal wire reinforcement layer via an intermediate rubber layer or directly. 40 ~
It is known that the second metal wire reinforcing layer is braided at an angle of 50 degrees and the outer surface rubber layer is provided on the outer periphery of the second metal wire reinforcing layer (Act No. 1-333904). However, since all the metal wires are used as the reinforcing layer, the hose has a heavy weight and is difficult to handle. Further, in the hose used for the above-mentioned application according to the present invention, when a person holds the tip of the hose for working, or when the hose is set in a hole excavated by manpower to work. From this point of view, there has been a demand for a lightweight hose.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a low elongation high pressure hose which has sufficient pressure resistance, is lightweight, and has a small elongation against a tensile load.

[0006]

In order to achieve the above object, the low elongation high pressure hose of the present invention comprises one or more metal wire braid layers provided on the outer peripheral surface of a cylindrical inner rubber layer. The first reinforcing layer having an average value of braid angles of ± 52 to 57 degrees with respect to the axial direction of the hose of all of these layers, and the outer peripheral surface of the first reinforcing layer directly or through an intermediate rubber layer. It consists of one or more organic fiber braid layers provided by
A second reinforcing layer having a braid angle of ± 40 to 50 degrees with respect to the axial direction of the hose of each of these layers and an outer rubber layer provided on the outer peripheral surface of the second reinforcing layer are provided. Further, the organic fibers are preferably aramid fibers which are low density, low elongation and high reinforcing fibers.

[0007]

The low elongation high pressure hose of the present invention comprises, as the first reinforcing layer, one or more metal wire braid layers, and the average value of the braid angles of these metals with respect to the axial direction of the hose is ±.
By arranging at a braiding angle of 52 to 57 degrees, more preferably ± 53.7 to 55.7 degrees, a pressure-resistant role is exerted against dimensional changes in hose diameter and length and breaking pressure. The second reinforcing layer is made up of one or more organic fiber braid layers, and the layers are braided at an angle of ± 40 to 50 degrees with respect to the axial direction of the hose. Of the hose can be restrained from being stretched in the axial direction with respect to a tensile load, and can also play a role of weight reduction. As a result, the hose itself can be provided with sufficient pressure resistance, and the hose axis line can be lightweight. Elongation against a tensile load in the direction is also suppressed.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A specific embodiment 1 of the low extension pressure resistant hose 1 according to the present invention will be described with reference to FIG. FIG. 1 is a partial side view of the low-elongation high-pressure hose according to the present invention in which each layer is partially stripped off.
2 is the inner rubber layer, 3 is the axial direction of the hose 1, 4 is a metal wire braid layer consisting of one layer as the first reinforcing layer, 5 is an intermediate rubber layer, 6 is organic fiber knitting as the second reinforcing layer Braiding,
7 is an outer rubber layer.

The low elongation high pressure hose 1 of this figure is a braid on the outer peripheral surface of the cylindrical inner rubber layer 2 with respect to the axial direction 3 of the hose 1 and a theoretical static angle of ± 54.7 degrees. A first reinforcing layer 4 made of a single layer of metal wire braided at an angle is provided, and an intermediate rubber layer 5 and an axial direction 3 of the hose 1 are braided on the outer peripheral surface of the first reinforcing layer 4. Angle ± 40-50
The second reinforcing layer 6 made of aramid fiber, which is a low-density, low-elongation, high-reinforcing organic fiber, and the outer rubber layer 7, which is a coating layer, are sequentially arranged. The low-density, low-elongation, high-reinforcing organic fiber refers to a fiber having a density of 1.5 g / cm ³ or less, a tensile strength of 220 Kgf / mm ² or more and a breaking elongation of 4.5% or less.

FIG. 2 is a partial side view of the low-elongation high-pressure hose according to the second embodiment of the present invention in which each layer is partially stripped off. In FIG. 2, 1 is a low-elongation high-pressure hose and 2 is an inner surface. Rubber layer,
3 is an axial direction of the hose 1, 4 is a first reinforcing layer composed of two layers of a metal wire braided layer composed of an inner layer of 4a and an outer layer of 4b, 5 is an intermediate rubber layer, and 6 is one aramid fiber 2 is a second reinforcing layer made of a braid, and 7 is an outer rubber layer.

The low-extension high-pressure hose 1 shown in FIG. 1 is an inner layer made of a metal wire on the outer peripheral surface of a cylindrical inner rubber layer 2 with an intermediate rubber layer 5 interposed in the axial direction 3 of the hose 1. 4a
The braid angle of ± 52 to 54 degrees, the outer layer 4b made of metal wire is ± 54 to 56 degrees, and the average value of these angles is close to the theoretical static angle of ± 54.7 degrees. One reinforcing layer 4 is provided, and on the outer peripheral surface of the first reinforcing layer 4,
The intermediate rubber layer 5 and the hoses on the outer peripheral surface of the intermediate rubber layer 5
A second reinforcing layer 6 made of aramid fibers having a braid angle of ± 40 to 50 degrees with respect to the axial direction 3 of the cloth 1 and an outer rubber layer 7 as a coating layer are sequentially arranged.

The angle of the first reinforcing layer 4 composed of one or more metal wire braids with respect to the axial direction 3 is ± 5.
The reason why the angle is close to the theoretical resting angle of 4.7 degrees is that the strength of the hose 1 in the circumferential direction and the strength of the axial direction 3 are equal, whereby the diameter and length of the hose 1 are determined. This is because the first reinforcing layer 4 plays a role of pressure resistance against changes and breaking pressure. Further, one or more second reinforcing layers 6 made of an aramid fiber, which is an organic fiber having a low elongation and a high reinforcing property and a density of about 18% as compared with a metal wire, are formed within an angle of ± 40 to ± 40 to the axial direction 3. The reason for setting the angle to 50 degrees is that the second reinforcing layer 6 suppresses the elongation of the hose 1 against the tensile load in the axial direction 3 and plays the role of weight reduction. That is, the smaller this angle is, the smaller the elongation of the hose 1 can be made. On the other hand, if the angle is too small, the hose becomes difficult to bend, so that the hose is hard to bend and wound around the reel or the like. The above lower limit of the angle is ± 40 degrees, and the upper limit is ± 50 degrees, because it may cause unfavorable results when it is transported or used while being wound around a reel. This is because the effect of suppressing the elongation of the hose 1 with respect to the tensile load in the axial direction 3 becomes insignificant when it exceeds the range. Here, as the organic fibers, fibers such as vinylon and polyester can be used, but aramid fibers are preferable from the viewpoint of the effect of suppressing elongation under a tensile load. Further, in the low elongation high pressure hose 1 of the present invention, the intermediate rubber 5 may or may not be provided. Further, the first reinforcing layer 4 may be a single layer, two layers or more depending on the operating pressure of the hose. Generally, as the first reinforcing layer 4, one layer is used up to a working pressure of the hose of 140 kgf / cm ^2, and two layers or more are used at a pressure higher than that. When the braid angle of the metal wire of the first reinforcing layer 4 is two,
The inner reinforcing layer is ± 52 to 54 degrees, the outer reinforcing layer is ± 54 to 56 degrees, and the average value of the braid angles of the two layers is the theoretical static angle of 54.7 degrees with respect to the axial direction 3 of the space 1. Approach. Changing the braiding angles of the inner reinforcing layer and the outer reinforcing layer so as to bring the average value closer to the theoretical static angle of 54.7 degrees is the reason why a general braiding machine is currently available that can continuously braid two layers. It is also because of the performance of. However, depending on the application and size of the hose, the braid angle of the first reinforcing layer 4
In the case of one layer, ± 52 to 57 with respect to the axis 3 of the hose
In the case of two layers or two or more layers, the average braid angle of those layers may be ± 52 to 57 degrees.
Further, also for the second reinforcing layer 6, the braiding angle of each layer may be ± 40 to 50 degrees and may be two or more layers for the purpose of suppressing the stretchability against a tensile load to the minimum. Further, the inner rubber layer 2, the intermediate rubber layer 5 and the outer rubber layer 7 constituting the low elongation high pressure hose 1 of the present invention may be the same as those used in the conventional high pressure hose.

Next, an example of a procedure for manufacturing the low elongation high pressure hose 1 will be described. This low extension high pressure hose 1
In order to manufacture the above, first, an inner rubber layer 2 is formed on a mandrel by an extruder, and a metal wire of one layer is further formed on the mandrel by a braiding machine in the axial direction 3 of the hose 1. A continuous braid at an angle close to ± 54.7 degrees, or two braid machines connected to each other continuously braid two layers of braid at the above-mentioned desired angles. The inner rubber layer 2 is braided and coated so that the average value of the angles becomes the theoretical static angle ± 54.7 degrees. Subsequently, the second reinforcing layer 6 is formed on the outer peripheral surface of the first reinforcing layer 4 by braiding the aramid fiber at ± 40 to 50 degrees with respect to the axial direction 3 of the hose 1 by a braiding machine. At this time, the sheet-shaped intermediate rubber layer 5 is inserted between the first reinforcing layers 4 and between the first reinforcing layer 4 and the second reinforcing layer 6 by a generally known method. After coating the outer peripheral surface of the second reinforcing layer 6 with the outer rubber layer 7 extruded by an extruder, a generally known method, for example, coating with lead or lapping with a cloth, The hose 1 is manufactured by subjecting it to a sulfur treatment, then removing lead and cloth, and extruding or pulling out the mandrel hydraulically.
The steps of providing each layer of the hose 1 may be performed independently or continuously.

[0014]

[Test Example] The low elongation pressure resistant hose 1 used in Example 1 is
A piano wire 32 having a wire diameter of 0.33 mm is formed on the outer peripheral surface of a cylindrical inner rubber layer 2 having an inner diameter of 19.0 mm and a rubber thickness of 2.0 mm.
A first reinforcing layer 4 is formed by braiding X6 metal wires at an angle of ± 54.7 degrees with respect to the axial direction 3 of the hose 1, and the outer peripheral surface of the first reinforcing layer 4 is provided. In addition, an intermediate rubber layer 5 having a rubber thickness of 0.4 mm and 32 x 3 aramid fiber cords having a code size of 1500 denier (using a trade name Technora manufactured by Teijin Ltd.) are arranged in the axial direction 3. One second reinforcement layer 6 braided at an angle of ± 45 degrees
The outer rubber layer 7 covering the outer peripheral surface of the second reinforcing layer 6 has a thickness of 1.5 mm and is sequentially provided.

The hose for high pressure used in Comparative Example 1 was the same as Example 1 except that the intermediate rubber layer 5 and the second reinforcing layer 6 were removed.
It has a hose structure similar to.

The high-pressure hoses used in Comparative Example 2 consisted of 32 × 4 piano wires having a diameter of 0.33 mm in the axial direction 3 of the hose 1 instead of the second reinforcing layer 6. It has the same hose structure as in Example 1 except that the metal wires were braided at an angle of ± 45 degrees.

(Test method) In the test, the tensile load was increased by 20 kgf to each of the hoses up to 200 kgf, and the elongation (%) of the hose at that time was measured. The result is shown in FIG. Moreover, the weight per unit length (1 m) was measured.

In FIG. 3, reference numeral A is the above-mentioned comparative example 1.
And the symbol B is the hose of the structure of the first embodiment.
The symbol C is a hose having the structure of the comparative example 2 described above. From these results, the structure A of the comparative example 1 has a large elongation against a tensile load and does not meet the purpose of the present invention, but the hose structure B of the example 1 has a larger tensile load than the hose structure C of the comparative example 2. The results are comparable to the elongation, indicating that the elongation with respect to the tensile load is sufficiently suppressed and the object of the present invention is achieved. On the other hand, the hose structure A of Example 1 had a unit weight of 680 g (g), which was about 15% less than the hose structure C of Comparative Example 2 of 800 g (g). It was Furthermore, when the pressure resistance was sufficiently tested, it was found that for all hoses, the normal pressure was 140 kgf / cm ² (13.7M
It has been found that it is possible to sufficiently withstand the internal pressure up to Pa).

Furthermore, another low extension pressure resistant hoist according to the present invention.
The second embodiment will be described with reference to FIGS. 2 and 4. The low extension pressure-proof hose 1 shown in FIG. 2 used in Example 2 has a cylindrical inner surface rubber layer 2 having an inner diameter of 12.7 mm and a rubber thickness of 2.2 mm, and a piano wire having a wire diameter of 0.30 mm on the outer peripheral surface thereof. 24X
Inner reinforcing layer 4a formed by braiding eight metal wires at an angle of ± 52.5 degrees with respect to the axial direction 3 of the hose 1.
A first reinforcing layer 4 consisting of two layers braided at an angle of ± 55.5 degrees is provided as an outer reinforcing layer 4b on the outer periphery of the outer rubber layer 5 having a thickness of 0.4 mm. On the outer peripheral surface of the intermediate rubber layer 5 having a rubber thickness of 0.3 mm, and on the outer peripheral surface of the intermediate rubber layer 5, 24 x 3 aramid fiber cords having a code size of 1500 denier (trade name: techno manufactured by Teijin Limited) -Use La) ± 45 with respect to the axial direction 3
The thickness of the one layer of the second reinforcing layer 6 braided at an angle of 1 degree and the thickness of the outer rubber layer 7 covering the outer peripheral surface of the second reinforcing layer 6 are 1.
2 mm are provided in sequence.

The high-pressure hose used in Comparative Example 3 had the same hose structure as in Example 2 except that the intermediate rubber layer 5 and the second reinforcing layer 6 were removed from the structure of Example 2. Have.

The hose for high pressure used in Comparative Example 4 is the same as the second reinforcing layer 6 of Example 2 except that the hose 1 has an axial direction 3
On the other hand, the hose structure is the same as that of the second embodiment except that a metal wire made of 24 × 7 piano wires having a wire diameter of 0.30 mm is braided at an angle of ± 45 degrees.

(Test Method) The test was based on the method described above.

In FIG. 4, reference numeral a is the above-mentioned comparative example 3.
The hose having the structure described above is shown. Reference numeral b is the hose structure of the second embodiment, and reference numeral c is the hose having the structure of the comparative example 4 described above. From this result, the hose structure b of Example 2 was obtained.
Shows that the elongation against tensile load is comparable to that of the hose c having the structure of Comparative Example 4, and that the elongation against tensile load is sufficiently suppressed. It is shown that the hose structure a has a large elongation against a tensile load and does not meet the purpose of the present invention. The hose structure b of Example 2 had a unit weight of 690 g (g), whereas the hose structure c of Comparative Example 4 had a unit weight of 790 g (g), and the unit weight was about 1 g.
It was reduced by 3%. Furthermore, when the pressure resistance was sufficiently tested, it was found that the normal pressure 21
For internal pressure up to 0 kgf / cm ² (20.6 MPa),
It was found that it could be used sufficiently.

[0024]

According to the present invention, as compared with a conventional hose having a reinforcing layer made of a metal wire, it has sufficient pressure resistance,
It has become possible to provide a low-extension high-pressure hose with a large reduction in weight and a small elongation with respect to a tensile load in the hose axis direction.

[Brief description of drawings]

1 is a low elongation high pressure hose of Example 1 according to the present invention,
It is a partial side view in the state where each layer was partially stripped off.

2 is a low elongation high pressure hose of Example 2 according to the present invention, FIG.
It is a partial side view in the state where each layer was partially stripped off.

FIG. 3 is a plot of changes in hose elongation with respect to tensile load for Example 1 and Comparative Examples 1 and 2.

FIG. 4 is a plot of changes in hose elongation with respect to tensile load for Example 2 and Comparative Examples 3 and 4.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Low elongation high pressure hose 2 Inner surface rubber layer 3 Axial direction of hose 4 First reinforcing layer 4a Inner reinforcing layer 4b Outer reinforcing layer 5 Intermediate rubber layer 6 Second reinforcing layer 7 Outer surface rubber layer

Claims (2)

[Claims] 1. A cylindrical inner rubber layer comprising one or more metal wire braid layers provided on the outer peripheral surface, and the average value of the braid angles of these layers relative to the axial direction of the hose is ± 5.
2 to 57 degrees, a first reinforcing layer, and one or more organic fiber braid layers provided on the outer peripheral surface of the first reinforcing layer directly or via an intermediate rubber layer, and the hose of each of these layers A low-strength high-pressure ho, characterized in that it comprises a second reinforcing layer having a braiding angle of ± 40 to 50 degrees with respect to the axial direction, and an outer rubber layer provided on the outer peripheral surface of the second reinforcing layer. -Su. 2. The low elongation high pressure hose according to claim 1, wherein the organic fibers are aramid fibers having a low density, a low elongation and a high reinforcing property.