JPH0560274A - High-pressure rubber hose - Google Patents

Abstract

PURPOSE:To provide a high-pressure rubber hose exhibiting excellent resistance to a fluid acting as acid to a horse constituting material. CONSTITUTION:In a high-pressure rubber hose having one or a plurality of braided reinforcing layers on the upper layer of an inner layer rubber tube 1 and an outer layer rubber 6 covering the upper layer of the braided reinforcing layer, a specified polymer interrupting layer 2 is provided between the inner layer rubber tube and the braided reinforcing layer.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a high pressure rubber hose. More specifically, the present invention relates to a high-pressure rubber hose that exhibits resistance to a fluid that acts as an acid on a hose constituent material.

[0002]

2. Description of the Related Art High-pressure rubber hoses are used as flexible piping materials for various high-pressure devices.

This type of high-pressure rubber hose is constructed by providing one or a plurality of braided reinforcing layers on the inner rubber tube and coating the outer layer rubber on the braided reinforcing layer.

As the material of the inner layer rubber tube, of course, rubber which can withstand the fluid moving in the inner layer rubber tube is preferable, and for example, when the fluid is oil, oil resistant rubber is preferable. Examples of the oil resistant rubber include nitrile rubber, styrene butadiene rubber, chloroprene rubber, ethylene propylene diene rubber and the like.

Further, the braided reinforcing layer material is preferably a high-strength fiber capable of preventing the deformation of the rubber hose due to high pressure. For example, strong rayon, polyester fiber, polyamide fiber, polyvinyl alcohol fiber, glass fiber and the like are used.

When two or more braided reinforcing layers are provided, it is customary to provide an intermediate rubber layer between them in order to prevent mutual rubbing between the braided layers and to improve the strength of the reinforcing layers.

As the outer layer rubber, a material which can withstand mechanical stress and environmental stress from the outside is preferable, and for example, chloroprene rubber, ethylene propylene diene rubber and the like are used.

Therefore, the high-pressure rubber hose is usually used in an environment where these constituent materials can withstand, that is, in a relatively mild piping environment.

However, in recent years, it is often used even in a severe environment. For example, it may be used even in a harsh alkaline atmosphere or an acidic atmosphere. In some cases, the fluid itself moving in the high-pressure rubber hose may be a severe corrosive substance.

[0010]

As described above, the conventional high-pressure rubber hose is formed by providing one or more braided reinforcing layers on the inner rubber tube, and coating the outer layer rubber on the braided reinforcing layer. Therefore, when used for many years, an extremely small amount of the fluid may gradually diffuse and permeate the inner rubber tube to reach the braided reinforcing layer, or, in a severe case, reach the outer rubber. On the contrary, a trace amount of corrosive gas, liquid, water, etc. in the outside world may gradually diffuse and permeate the outer layer rubber to reach the braided reinforcing layer, or in severe cases, reach the inner layer rubber tube. ..

Since such an amount of diffusion and permeation is extremely small, there is usually no problem, but in recent years, the temperature of the atmosphere used is high, the mechanical stress received is large, and the longevity of various high-voltage devices themselves is extended, resulting in many years of use. As they are used, there is a concern about deterioration of the combined action due to these penetrating substances.

For example, when the external environment is hot and humid and the internal fluid moving in the inner layer rubber tube acts as an acid on the hose constituent material, the braided reinforcing layer and the outer layer rubber cause a combined action deterioration. Sometimes.

The present invention has been made in view of such a point, and its purpose is to solve the above-mentioned drawbacks of the prior art so that the internal fluid moving in the inner rubber tube is different from the hose constituent material. Another object of the present invention is to provide a high-pressure rubber hose that can effectively prevent compound deterioration of a fluid that acts as an acid.

[0014]

SUMMARY OF THE INVENTION The gist of the present invention is that an inner layer rubber tube has an upper layer having one or a plurality of braided reinforcement layers, and the braided reinforcement layer has an upper layer coated with an outer rubber layer. In a high-pressure rubber hose, 100 m of distilled water at a temperature of 20 ° C was used between the inner rubber tube and the braided reinforcement layer.
pH of immersion liquid after immersion of 5 g in 1 for 1 hour
In the high pressure rubber hose, a polymer blocking layer having a ratio of 9 or more is provided.

In the present invention, 100 distilled water having a temperature of 20 ° C.
p of immersion liquid when 5 g was immersed in 1 ml for 1 hour
The polymer thin layer having H of 9 or more is a rubber sheet layer or a plastic film layer.

These rubber sheet layers or plastic film layers were added to 5 ml of 100 ml of distilled water at a temperature of 20 ° C.
The alkaline substance is blended or bonded so that the pH of the immersion liquid when g is immersed for 1 hour becomes 9 or more.

As a method for laminating alkaline substances,
Whether the high-concentration blended sheet of alkaline substance fine powder is simply vulcanized or heat-bonded between the two rubber sheet layers or between the two plastic film layers or between the rubber sheet layer and the plastic film layers, etc. ,
Alternatively, stick with a rubber adhesive or the like. Alternatively, microcapsules of an alkaline substance may be used.

In this case, the reason why the alkaline substance fine powder high-concentration blend sheet is laminated in the middle is that the intermediate alkaline substance fine powder high-concentration blend sheet contains a large amount of the alkaline substance fine powder, so that the flexibility is poor. Is.
Degradation of other hose materials due to scattering of fine alkaline substance powders can be effectively suppressed by laminating two rubber sheet layers or two plastic film layers or laminating a rubber sheet layer and a plastic film layer. it can.

In the present invention, the alkaline substance includes sodium hydroxide, potassium hydroxide, calcium hydroxide, magnesium hydroxide, ammonium salt and the like. Of course,
In the present invention, the alkaline substance may be a blend of these.

It is also possible to use an organic amine or the like.

In the present invention, the polymer blocking layer has a temperature of 20.
When 5 g was immersed in 100 ml of distilled water at ℃ for 1 hour, the pH of the immersion liquid was adjusted to 9 or more.
When H is 9 or less, it is difficult to quickly and smoothly neutralize the fluid that acts as an acid on the hose material that has reached the polymer blocking layer.

[0022]

The high-pressure rubber hose of the present invention is a high-pressure rubber hose in which one or more braided reinforcing layers are provided on the inner layer rubber tube, and the outer layer rubber is coated on the braided reinforcing layer. By providing a polymer blocking layer with a pH of the immersion liquid of 9 or more when 5 g was immersed in 100 ml of distilled water at a temperature of 20 ° C. for 1 hour between the braided reinforcing layer, it was possible to permeate and diffuse from the inner layer tube. The fluid that acts as an acid on the hose constituent materials and the high pressure rubber completely penetrate and diffuse from the outside of the hose to completely prevent the composite deterioration of the substance, and as a result, the inner rubber tube, the polymer barrier layer, the braided reinforcement layer, and the intermediate rubber. It is possible to effectively suppress deterioration of the outer layer, the outer layer rubber and the like, and to exhibit high reliability.

When the alkaline substance is microencapsulated with a water-soluble substance, it effectively neutralizes when a large amount of water permeates.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the high pressure rubber hose of the present invention will be described below with reference to the drawings.

FIG. 1 is an explanatory view showing an embodiment of the high pressure rubber hose of the present invention.

In FIG. 1, 1 is a rubber tube for the inner layer, 2 is a polymer blocking layer having a pH of 9 or more when 5 g is immersed in 100 ml of distilled water at a temperature of 20 ° C. for 1 hour, which characterizes the present invention, 3 is a first braid layer, 4 is an intermediate rubber layer, 5 is a second braid layer, and 6 is an outer rubber layer.

In one embodiment of the present invention, as the inner rubber tube 1, a styrene budien rubber tube having excellent oil resistance was used.

In one embodiment of the present invention, the polymer blocking layer 2 comprises 100 parts by weight of nitrile rubber, 15 parts by weight of fine potassium hydroxide powder, a vulcanizing agent, an antioxidant, a lubricant and a filler. A rubber sheet formed by appropriately blending was used.

In one embodiment of the present invention, the first braided layer 3 and the second braided layer 5 are composed of braided layers of polyvinyl alcohol fiber.

In one embodiment of the present invention, the intermediate rubber layer is made of a natural rubber sheet.

Further, in one embodiment of the present invention, the outer rubber layer 6 is made of chloroprene rubber.

In one embodiment of the present invention the polymeric barrier layer 2
The fluid permeation rate of is faster than the fluid permeation rate of the inner rubber tube 1. This is because when the fluid permeation rate of the polymer barrier layer 2 is slower than the fluid permeation rate of the inner rubber tube 1, the fluid permeated and diffused from the inner rubber tube 1 is between the inner rubber tube 1 and the polymer barrier layer 2. Stay in
As a result, interphase deterioration and hose bulge are induced.

In the present invention, the inner rubber tube and the outer layer are made of a rubber material.
It may be composed of an ionomer of a rubber material and a plastic material, or may have a two-layer structure of a rubber and a plastic material, if necessary. For example, the inner rubber tube may have a two-layer structure in which a styrene-butadiene rubber tube is coated with a polyamide resin.

Next, the high pressure rubber hoses of the present invention shown in FIG. 1 were manufactured into high pressure rubber hoses of Examples and Comparative Examples in which the pH of the polymer blocking layer 2 was changed, and these high pressure rubber hoses were heated at a temperature of Accelerated deterioration was performed for 2 years in an atmosphere of 40 ° C. and 90% relative humidity, and the deterioration of the hose was observed. Table 1 shows the test results.

The hose strength is obtained by pulling a hose having a length of 50 cm in the longitudinal direction and determining its breaking strength (kg).

[0036]

[Table 1]

As can be seen from Table 1, p of the polymer blocking layer is
In Comparative Examples 1 to 3 in which H is 9 or less, the swelling failure occurs and the hose breaking strength decreases, whereas in Examples 1, 2, and 3 of the present invention, no abnormal appearance is observed and the hose breaking strength is also Excellent results are shown.

[0038]

The high-pressure rubber hose of the present invention, when an acidic fluid is circulated in the hose and used for a long period of time in a harsh atmosphere, a diffusion permeation acidic fluid from the inner layer tube and a diffusion permeation external component from the outer layer rubber. It is possible to completely suppress the combined deterioration with the above, and as a result, it is possible to obtain a highly reliable high-pressure rubber hose, which is industrially useful.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an embodiment of a high pressure rubber hose of the present invention.

[Explanation of symbols]

 1 Inner Layer Rubber Tube 2 Polymer Barrier Layer 3 First Braid Layer 4 Intermediate Rubber Layer 5 Second Braid Layer 6 Outer Rubber Layer

Claims (3)

[Claims] 1. A high-pressure rubber hose having one or a plurality of braided reinforcing layers as an upper layer of an inner rubber tube, and an upper layer of the braided reinforcing layer coated with an outer rubber layer, wherein the inner rubber tube and the braided reinforcing layer are provided. A high-pressure rubber hose provided with a polymer blocking layer having a pH of 9 or more when immersed in 100 ml of distilled water at a temperature of 20 ° C. for 1 hour. 2. The high-pressure rubber hose according to claim 1, wherein the polymer blocking layer is a rubber sheet layer. 3. The high-pressure rubber hose according to claim 1, wherein the polymer blocking layer is a plastic film layer.