JPS5817283A - Flexible hose reinforced by metallic wire - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flexible hose reinforced with metal wire. More specifically, although it uses metal wire with high tensile strength and low toughness, which was conventionally considered unusable for reinforcing high-pressure flexible hoses, it has excellent minimum burst pressure and durability against repeated impact. This invention relates to a high-pressure flexible hose that is superior to conventional hoses.

The general structure of a flexible hose for high pressure is to use a spiral metal wire between the innermost layer, an inner tube layer through which fluid passes, and the outermost layer, an outer cover layer for protection from the outside. A plurality of reinforcing layers wound around or knitted into a mesh are interposed with an intermediate layer interposed therebetween. By the way, the minimum bursting pressure P (
K4f/7) is generally given by the following formula.

Where, N: Number of metal wires T: Cutting load of metal wire (Kri f) θ: Execution angle of metal wire with respect to central axis of hose π: Circumference D: Diameter of reinforcing layer (Hata) From formula (1) As is clear, the minimum bursting pressure of a hose can be achieved by increasing the cutting load 'j (ffll, tensile strength) per metal wire, increasing the number N of metal wires, and increasing the number of reinforcing layers. It is conceivable that it can be made larger by increasing it.

However, although this is clear, conventional high-pressure flexible hoses have a wire diameter of 0 for the following reason.
．． A metal wire with a tensile strength of 285 gmm or more is not used, and a metal wire with a tensile strength of 3101 or more with a wire diameter of 0.25 u or more Q and less than 5 mm is not used. In other words, a metal wire with a tensile strength exceeding the above-mentioned limit value will inevitably have lower toughness, and as a result, the hose's durability against repeated impact (called impulse performance) will be lowered. It is. Dynamic durability tests of hoses have shown that the reinforcing metal wires are not only subjected to tensile and directional forces, but are also subjected to bending and shearing stresses. Therefore, the impulse performance of a hose with low toughness will be significantly reduced. (Gluck'auf Vol. 15, No. 8, p. 384~
39o.

Watanabe, 1966, load and selection of high-pressure hydraulic ports for mining).For these reasons, the lower limit target is 30 torsions measured by the JIS G 3522 test method, and the number of torsions above that ( The optimum tensile strength was selected within the range of toughness). Figure 4 shows the tensile strength vs. number of twisting curves of currently available metal wires. In the past, it was practically only possible to use metal wires with performance within the range of the arrow direction with line A in the figure as the boundary. There wasn't. Therefore, as is clear from equation (1), there is a limit to which the minimum bursting pressure of the hose cannot be increased. In this way, the fact that there is an i-field in the minimum burst pressure naturally places a limit on the normal pressure (normal pressure is usually 1/8 of the minimum burst pressure (British B53640 Draft 19-64).
), the text is 1/4 (American sAE standard)) expansion of the functions of high-pressure flexible hoses; ing.

The purpose of the present invention is to solve the above-mentioned conventional problems, and to achieve even better impulse performance even at ultra-high pressure than before, even though it uses a metal wire with high tensile strength and low toughness.
Although it has the same minimum burst pressure and impulse performance as conventional products, it can reduce the weight of the hose, and the outer diameter of the hose can also be reduced, making it possible to make the hose itself smaller and lighter. The aim is to provide a hose.

The flexible hose of the present invention that achieves the above object is a flexible hose provided with a reinforcing layer of metal or wire, in which the metal wire has a wire diameter of 0.50 mm or more and a tensile strength of 0.50 mm or more and somm or less.
85 vIIi or more 365 Q/, less than 15 times or more, and the average wire density of the hose is 9
It is characterized by a ratio of 2.0±4.0.

Furthermore, in a flexible hose provided with a reinforcing layer of metal wire, the metal wire has a wire diameter of 0.25 mm or more and less than 0.5 mm, and a tensile strength of 315 or higher and 395 or higher. - Below,
The hose is characterized in that the number of twists is 15 or more, and the average wire density of the hose is 92.0±4.0%.

In this shield, tensile strength is defined as "
It is measured by "Tensile test" and the number of twists is also measured by "Torsion test" of JIS G 3522.
'measured by'. In particular, the latter torsion test means the number of times the thread breaks when the measuring length is i'o o times the wire diameter d' of the metal wire, that is, 100 d'.

In addition, the wire average density is expressed by the following formula for each reinforcing layer: wire density σ (4'/cos θ)
': The wire diameters θ, N, D, and π of the Kanasu wire mean the average of the values of each layer as in equation (1).

According to the above-mentioned disastrous flexible hose, toughness (twisting)
Although the metal wire reinforcement layer has a reduced toughness, the reduced toughness does not affect the hose performance, but rather increases the tensile strength, resulting in minimal fracture, increased pressure, and associated impulse performance. A significant improvement in the results has been confirmed. This effect reduces the wire uniform density to 92.0±4.
One reason is thought to be that the range was limited to zero.

Generally, as the wire density of a hose increases, there is less clearance for the metal wire to "move" during hose operation. That is, 1. In dynamic durability tests, metal wires are not only subjected to force in the tensile direction, but also subjected to repeated stress in the bending and shear directions, but as the wire density increases, the "moving" gap decreases. This will reduce the amplitude of this repeated stress. Therefore, in the pose of the present invention having a high wire density, the amplitude of repeated stress applied to the metal wire is reduced, and its durability is improved.

That's probably why. However, if the wire density is too high,
Since the flexibility of the hose decreases and the original function of the hose decreases, it is necessary to set an upper limit on the wire density within a range that allows the flexibility.

The following description will be made with reference to the drawings.

FIG. 1 shows a cross-sectional view of a high-pressure flexible hose according to an embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a rubber inner tube 1 made of plastic. This inner tube pipe 1 is for passing fluid (oil, water, air, etc.) into the inner pipe, so in order to prevent this fluid from leaking and to allow it to flow smoothly, it must be flexible enough to suit the properties of the fluid. Make sure that Seizaisha is chosen. A plurality of reinforcing layers 2 made of metal fN2a are wound around the outside of the inner tube 1'' with intermediate layers 6 interposed therebetween. The metal wire 2a may be knitted to form the reinforcing layer 2, or may be spirally wound in the same direction to form the reinforcing layer 2. When winding the latter spirally, it is preferable to arrange the winding directions of adjacent layers to be different from each other in the multilayer reinforcing layer. The intermediate layer 3 fills the spaces between the reinforcing layers 2 and the metal wires 2a, and serves to prevent mutual contact and friction. Reference numeral 4 designates an outer cover layer for protecting the reinforcing layer 2 from the outside. The number of reinforcing layers 2 may be arbitrary depending on the purpose, but it is generally preferable to provide an even number of 2.4.6 layers.

In the hose configuration as described above, the metal wire 2a constituting the reinforcing layer 2 has a wire diameter of 0.5 mm or more and 0.8 mm or less, a tensile strength of 285 or more and 3651 or less, and a wire diameter of 0.8 mm or more and 3651 or less.
If the tensile strength is between 25 and less than 0.5, the tensile strength is 315) 4d.
The hose is selected such that the number of twists is 15 or more, and the average wire density of the hose is 92.0±, 4.0%.

Hereinafter, specific effects will be explained with reference to Examples.

The impulse performance test method evaluated in the examples was conducted in accordance with the impact pressure test method of 5AEJ343r3, and the number of times the hose broke was defined as the impulse performance. However, the normal pressure was defined as % of the minimum bursting pressure of each sample. The pressure waveform is an SAE rectangular waveform represented by the shaded area as shown in Figure 2. The test oil was SAE #30 equivalent oil, the oil temperature was 120℃, and the installation was at a 180° pendant (-8
-12), 90' vent resistance -16 or higher).

Moreover, the pressure resistance test method for the minimum burst pressure evaluated in the examples was carried out according to the fracture test method of JIS K 6349-1975.

Furthermore, in the flexibility test method evaluated in the examples, a 6° hose with an outer diameter of d is prepared with a length of 10×d or more, as shown in FIG. A three-point bending test was conducted with the distance set to 8Xd. As shown in FIG. 3(B), flexibility was determined by a load P when the amount of strain was 4Xd. In the figure, 32 is a load applying rod, 66 is a load cell, and 34 is a recorder.

Example 1 Each metal wire 7161 to /I66 having a wire diameter of 0.6 mm and having a different tensile strength and number of twists as shown in Table 1 was prepared, each was used as a reinforcing layer, and the wire average density was We have manufactured various types of flexible hoses with different standards. In both cases, the number of reinforcing layers is 4, the metal wire is spirally wound, and 4
The diameters of the reinforcing layers were 37.5 mm, 39.0 mm, 40.5 mm, and 42.0 mm, respectively.

Table 1 As a result of measuring the minimum burst pressure and impulse performance of each of the above hoses, the results shown in Table 2 were obtained. Table-2
The numbers inside are all indexes when the performance of the sample/161 hose with an average wire density of 82% is set as 100, the upper row is the minimum burst pressure, and the lower row (in parentheses) is the impulse performance.

(Margins below this page) Table 2 (σ: Wire average density) In Table 2, the portions marked with red correspond to the hoses of the present invention, and all have impulse performance of 125 or higher. From the above results, the minimum bursting pressure of each hose is a little lower than the calculated bursting pressure of equation (1) in the range where the toughness of the metal wire is low (high tensile strength range) due to its influence, but it is approximately , is confirmed to increase as the tensile strength and number (density) of metal wires increases stepwise.

On the other hand, the impulse performance of conventionally used hoses made of metal wires is constant regardless of the average wire density of the dog i-hose, but in the present invention.

It can be seen that a corresponding high tensile strength, low toughness metal wire exhibits better performance than the conventional hose in the optimal wire average density region.

Next, sample/161. A5 wire average density 80.
The table below shows the flexibility of each hose from 0 to 98.0%.
3. The table shows wire average density 94.0%,
/165 hose flexibility is expressed as an index of 1.

Table 3 As is clear from Table 3, hoses with a wire average density of 98% have substantially lost their flexibility.

Example 2 Using the same metal wires /161 to /166 as in Example 1, a flexible hose with six reinforcing layers was manufactured.

The metal wire of each reinforcing layer is spirally wound, and the diameters of the six layers are 37.5ii, 39.0+m, and 40.5mm, respectively.
, 42.0 Dragon, 43.51J 45.0 mw, closed.

As a result of measuring the minimum burst pressure and impulse performance of each hose, the results shown in Table 4 were obtained. All numbers in Table 4 are sample rot 1, wire average density 82.0
% hose performance as 100, the upper row is the minimum burst pressure, and the lower row (in parentheses) is the impulse performance.

(Margins below this page) Table 4 In Table 4, the portions marked with red correspond to the hoses of the present invention, and all have impulse performance of 125 or higher. As in Example 1, it can be seen that a metal wire with high tensile strength and low toughness corresponding to the present invention and having an optimal average wire density range exhibits performance superior to conventional hoses.

Further, in the same manner as in Example 1, when the flexibility of the hose was tested, it was found that a wire having an average density of 97% or more did not substantially have the function as a hose.

Example 3 Metal wires /167 to #612 having a wire diameter of 0.4 mm and having different tensile strength and number of twists as shown in Table 5 were prepared, each was used as a reinforcing layer, and the wire average We manufactured various hoses with different density levels. In both cases, the number of reinforcing layers is 4, the metal wire is spirally wound, and the diameters of each of the 4 reinforcing layers are 24, 3, and 25.4111, respectively.
．． 26.5 and 27.6.

Table 5 As a result of measuring the minimum burst pressure and impulse performance of each of the above hoses, the results shown in Table 6 were obtained. Table-6
The numbers inside are all indexes when the performance of sample A 7 , a hose with an average wire density of 82, is taken as 100; the upper row is the minimum burst pressure, and the lower row (in parentheses) is the impulse performance.

Table 6 In Table 6, the portions marked with sharpness correspond to the hoses of the present invention, and all have impulse performance of 125 or higher. As is clear from the above results, similar to Example 1, the high tensile strength, low toughness metal wire corresponding to the present invention exhibits better performance than the conventional hose in the optimal wire average density region. I understand that.

Moreover, the results of a similar flexibility test showed that the wire with an average density of 98 inches was not flexible enough to be used practically as a hose.

As explained above in detail with each example, the range of physical properties of metal wires that have not been used in the past, namely the wire diameter Q,
For metal carp of 5i+m or more and 0.8n or less, the tensile strength is 28
5- or more 365 ■ 9 or less, preferably 320 or more 3
65'Ad or less, and the wire diameter is 0.25mm or more and 0.25mm or less.
For metal wires less than 5IIK, the tensile strength is 315 to 395 or more.
Use a metal wire for the reinforcing layer with an immediate At or below, preferably 3401 or more and 395 twists or less, and the number of twists in any case is 15 or more, and the average wire density of the hose is 9
By setting the range to 2.0±4.0%, the minimum bursting pressure of the high-pressure flexible hose has been increased from approximately 1.3 times to 1.7 times.
In addition, impulse performance (durability) has been increased from approximately 1.25 times to 1.
6 times the conventional standard hose (tensile strength of metal wire 240'
Ad (for 0,6φ fight), 260 ”l//, a (
This is improved compared to the case of 0.4φ dragon; average wire density of 82 cm).

Therefore, according to the flexible hose of the present invention, a hose that conventionally required six reinforcing layers can now be provided with four reinforcing layers, and as a result, the weight of the hose can be reduced, and the hose The outer diameter can also be reduced, and the hose itself can be made smaller and lighter. Therefore, it is possible to make the hydraulic system more compact and sophisticated.

Note that the present invention can be applied not only to hydraulic fluids but also to other fluids such as water and air.

・1

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a flexible hose that is an embodiment of the present invention.
Figure 2 is a diagram showing the relationship between pressure and cycles, showing the pressure waveform in an impulse test. It is a number curve diagram. 1... Inner tube pipe, 2... Reinforcement layer, 2a...
-Metal wire, 3...middle layer, 4...outer cover single layer. Agent: Patent Attorney Shin Ogawa − Patent Attorney Ken Noguchi Patent Attorney Kazuhiko Saishita I UA Figure 2 (A') CB) Figure 3

Claims (1)

[Claims] 1. A flexible hose provided with a reinforcing layer of metal wire,
The metal wire has a wire diameter of 0.501111 or more and 0.80111
Hereinafter, a hose reinforced with a metal wire having a tensile strength of 285 (- to 365- or less), a number of twists of 15 or more, and an average wire density of 92.0±4.0% is used. Flexible hose. 2. In a flexible hose provided with a metal reinforcing layer, the metal wire has a wire diameter of 0.25 mw or more and less than 0.5 n, a tensile strength of 3151 or more and 395 twists or less, and a number of twists of 15 or more times. Yes, and the average wire density of the hose is 92.0±4.
A flexible hose reinforced with metal wire that is characterized by its zero strength.