JP3025100B2 - Reinforced rubber hose - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reinforced rubber hose used for dredging and for transporting oil and other fluids.

[0002]

2. Description of the Related Art Conventionally, the above-mentioned reinforced rubber hose has a sectional structure as shown in FIG. That is, the reinforcing rubber hose is formed by the inner rubber layer 91 and the reinforcing layer 9 from the inner peripheral side.
2. An intermediate rubber layer 93 including a rigid member 93a composed of a spiral wire or a ring, a breaker layer 94, and an outer rubber layer 95 are sequentially laminated.

As the inner rubber layer 91, a material having excellent corrosion resistance to a fluid to be transported is used. The reinforcing layer 92
It is configured to include a fiber cord arranged so as to form a predetermined angle (hereinafter, referred to as a cord angle) with respect to the hose axis direction, and mainly contributes as a pressure-resistant layer. The rigid member 93a such as a helical wire prevents the reinforcing rubber hose from crushing or buckling due to bending, and particularly restricts the radial expansion (extension in the circumferential direction) of the reinforcing layer 92.
The breaker layer 94 prevents the rigid member 93a such as a spiral wire from being exposed to the outside and also prevents cuts due to external damage to the reinforcing rubber hose. As the outer rubber layer 95, a material having excellent weather resistance and the like is used.

In the above-described reinforced rubber hose, when the reinforcing layer 92 is cracked or broken for some reason, the internal fluid leaks out through the reinforcing layer 92 and flows out. If the leaked fluid is oil or a chemical, problems such as environmental pollution occur. In particular, if such a leak occurs at sea, the pollution becomes a very serious problem.

Therefore, as disclosed in Japanese Patent Publication No. 59-47188 and Japanese Utility Model Laid-Open Publication No. 2-41786, a reinforcing layer is
Consisting of a main reinforcing layer disposed on the inner peripheral side of the intermediate rubber layer and a sub-reinforcing layer disposed on the outer peripheral side of the intermediate rubber layer. When the main reinforcing layer is damaged, the sub-reinforcing layer holds the fluid to be transported. Thus, a reinforcing rubber hose that prevents leakage to the outside is provided.

[0006]

Incidentally, the breakage of the hose includes breakage due to extension in the axial direction of the hose and breakage due to expansion in the radial direction of the hose (elongation in the circumferential direction of the hose). In the state where the main reinforcing layer is broken as described above, the sub-reinforcing layer disposed on the outer peripheral side of the rigid member 93a bears the above-mentioned hose strength in both directions without supplementing the strength by the rigid member 93a. .

However, in the above-mentioned publication, the cord angle of the fiber cord of the sub-reinforcing layer is less than 50 degrees in the case of the sub-reinforcing layer disclosed in Japanese Patent Publication No. 59-47188. In the reinforcing material disclosed in Japanese Utility Model Laid-Open Publication No. 2-41786, the cord angle of the fiber cord of the sub-reinforcing layer is 30 to 53 degrees), and the sub-reinforcing causes a difference in breaking strength in both directions. Layers were used. For example, regarding the strength of the sub-reinforcing layer, the breaking pressure due to the elongation in the hose axis direction is 30.
If the breaking pressure due to the extension in the circumferential direction of the hose is 50 MPa, the hose will not function due to the breaking in the axial direction of the hose at an internal pressure of 30 MPa. The breaking strength becomes unnecessary. Further, such a fiber cord that bears unnecessary strength is also unnecessarily robust, and the cord arrangement is not efficient with respect to securing strength, for example, the cord length becomes unnecessarily long.

In Japanese Unexamined Utility Model Publication No. 2-41786, when the main reinforcing layer is broken, an internal pressure is instantaneously applied to the sub-reinforcing layer, and the sub-reinforcing layer is simultaneously fractured when the main reinforcing layer is fractured. There was a problem of doing it. further,
The strength of the main reinforcing layer against expansion in the hose radial direction is complemented by a rigid member disposed on the inner peripheral side of the main reinforcing layer, whereas the cord angle of the fiber cord of the main reinforcing layer is Was 45 degrees, and unnecessarily high strength was secured against elongation in the circumferential direction. For this reason, similarly to the case of the sub-reinforcing layer, there is a problem that the cord arrangement for securing the strength is not efficient.

An object of the present invention is to provide a reinforced rubber hose which solves the above-mentioned technical problems, can secure necessary strength by efficient cord arrangement, and can reliably prevent leakage of internal fluid. It is.

[0010]

According to the present invention, there is provided a reinforcing rubber hose in which a tubular reinforcing layer including a fiber cord is provided between a tubular inner rubber layer and an outer rubber layer. In addition, in a reinforcing rubber hose in which an intermediate rubber layer in which a helical or ring-shaped rigid member is embedded is provided, the reinforcing layer includes a main reinforcing layer laminated on an inner peripheral side of the intermediate rubber layer. Including a sub-reinforcement layer laminated on the outer peripheral side of the intermediate rubber layer, the fiber cord of the main reinforcement layer,
The fiber cord of the sub-reinforcing layer is disposed so as to form an angle of 35 to 40 degrees with respect to the axis of the hose. It is disposed at an angle of about 54 degrees 44 minutes with respect to the axis of the hose so that the breaking strength of the main reinforcing layer is substantially equal to the breaking strength of the main reinforcing layer between the intermediate rubber layer and the auxiliary reinforcing layer. Accordingly, there is provided a break-off peeling layer which causes peeling in order to separate the sub-reinforcement layer from the inner peripheral portion thereof over the entire length of the hose.

[0011]

According to the reinforced rubber hose having the above-mentioned structure, the ruptured layer on the inner peripheral side of the sub-reinforcement layer peels over the entire length of the hose with the rupture of the main reinforcement layer. Therefore,
Since the pressure of the internal fluid is applied over the entire inner peripheral surface of the sub-reinforcement layer, it is possible to prevent the sub-reinforcement layer from being broken due to the local load.

When the main reinforcing layer is broken, the sub-reinforcing layer mainly takes on the strength.
Since the fiber cords are arranged so that the breaking strength due to the extension in the hose axis direction and the breaking strength due to the extension in the circumferential direction of the hose are substantially equal, the fiber cords contribute equally to the breaking strength in both directions. In addition, the fiber cord does not become unnecessarily long. The cord angle of the fiber cord for making the two breaking strengths substantially equal to each other is preferably an angle near a so-called stationary angle of approximately 54 degrees 44 minutes with respect to the hose axis direction.

Further, since the cord angle of the fiber cord of the main reinforcing layer is set to 35 to 40 degrees, necessary strength can be efficiently secured. That is, an intermediate rubber layer including a rigid member is disposed on the outer peripheral side of the main reinforcing layer, and the rigid member complements the breaking strength due to the extension of the main reinforcing layer in the circumferential direction of the hose. Therefore, the cord angle of the fiber cord of the main reinforcing layer is preferably an angle of 20 to 40 degrees with emphasis on elongation in the hose axis direction. In addition, if the cord angle is less than 35 degrees, the hose is likely to buckle.
A cord angle of 40 degrees is preferred.

[0014]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. FIG. 1 is a schematic longitudinal sectional view of a reinforced rubber hose showing one embodiment of the present invention. Referring to FIG. 1, this reinforcing rubber hose A has an inner rubber layer 1, a main reinforcing layer 21 including a fiber cord, an intermediate rubber layer 3 including a helical wire 3a as a rigid member, and a main reinforcing member from the inner peripheral side. The layer 21 at the time of break, which peels off when the layer 21 breaks, the sub-reinforcing layer 22 containing a fiber cord, the breaker layer 4 for preventing cut damage due to external damage, and the outer rubber layer 5 having excellent weather resistance are sequentially laminated. I have.

The main reinforcing layer 21 is composed of a rubber layer containing a polyester cord C as a fiber cord, and at least two plies are laminated. As the main reinforcing layer 21,
The number of the laminated plies was selected so as to have a breaking strength capable of withstanding a pressure five times the working pressure, which is a normal design standard. Referring to FIG. 2, hose axis direction P of main reinforcing layer 21
Is set at 35 to 40 degrees in consideration of the flexibility and buckling resistance of the hose.

The spiral wire 3a has a diameter of, for example, 9.45.
mm, consisting of hard steel wire wound at a pitch of 35 mm.
The auxiliary reinforcing layer 22 is formed of a rubber layer including at least two plies of a polyester cord C made of the same material as the fiber cord on the main reinforcing layer 21 side. This main reinforcement layer 2
As 1, the number of the laminated plies was selected so as to have a breaking strength capable of withstanding a pressure twice as high as the working pressure. The cord angle of the cord of the sub-reinforcing layer 22 is set such that the breaking strength by elongation in the hose axis direction P and the breaking strength by elongation in the hose circumferential direction are equal in a state where the main reinforcing layer 21 is broken. It was set at approximately 54 degrees 44 minutes, that is, near 54 degrees 44 minutes, which is the stationary angle.

The peeling layer 20 at break is interposed between the intermediate rubber layer 3 and the sub-reinforcing layer 22, and is capable of peeling over the entire length of the hose when the main reinforcing layer 21 breaks. In a general reinforced rubber hose, an elongation of 1.5 to 2.5% occurs in the axial direction at a normal operating pressure, and an elongation of 10 to 15% occurs at a breaking pressure. Therefore, the elongation in the axial direction exceeds 10%. And peeled off.

Specifically, as the release layer 20 at break, FIG.
, A nylon woven fabric 20a (42
(0d, density of 53 / inch) are coated with a 0.2 mm thick rubber based on natural rubber, and two of them are laminated. In this state, the intermediate rubber layer 3 and the rubber 20c on the lower surface side of the woven fabric 20a are in a bonded state, and the rubber 20c on the lower surface side of the woven fabric 20a and the woven fabric 20a are bonded.
The rubber 20c between "a" and "a" is in a state of being slightly bonded through the gap between the woven fabrics. Rubber 20 on the upper surface side of woven fabric 20a
The same applies to the relationship between d and the auxiliary reinforcing layer 22. That is, the rubber 20c between the two woven fabrics 20a is slightly bonded to the upper and lower layers 22 and 3 through the space between the woven fabrics, and when the elongation in the axial direction exceeds 10% as described above, the woven fabric is woven. The rubber 20c between the cloth and the woven cloth 20a is peeled off.
The release layer 20 at break is not limited to the above-described one. For example, a canvas or a plain cotton woven cloth can be used as the woven cloth 20a.

According to this embodiment, as the main reinforcing layer 21 breaks, the breakage peeling layer 20 interposed between the intermediate rubber layer 3 and the auxiliary reinforcing layer 22 peels over the entire length of the hose. The pressure of the internal fluid is applied to the entire inner peripheral surface of the sub-reinforcing layer 22, so that the breakage of the sub-reinforcing layer 22, which is conventionally caused by a local load, can be prevented. Therefore, the internal fluid that has leaked out of the main reinforcing layer 21 can be reliably held by the sub-reinforcing layer 22, and leakage to the outside can be reliably prevented. Moreover, the above-mentioned peeling layer at break 20 is formed by the main reinforcing layer 21.
In a normal state in which no break occurs, the adhesive is adhered with a predetermined adhesive force. Therefore, there is no possibility that peeling occurs due to bending or the like in the normal state, and the peeled portion is damaged by rubbing.

Further, the cord angle of the fiber cord of the sub-reinforcing layer 22 which is mainly responsible for the strength when the main reinforcing layer 21 is broken is set to approximately 55 degrees 44 minutes which is near the stationary angle, and the extension in the hose axial direction is performed. The breaking strength due to expansion in the radial direction of the hose and the breaking strength due to expansion in the hose radial direction are substantially equal, so that the fiber cord can be used efficiently for securing strength, such as preventing the fiber cord from becoming uselessly long. .

Further, the main reinforcing layer 21, whose strength in the radial direction is reinforced by the intermediate rubber layer 3 including the spiral wire 3a, adjusts the cord angle of the fiber cord by 35 to 40.
Since there is a degree, the required strength can be efficiently secured. That is, the cord angle of the fiber cord of the main reinforcing layer 21 is preferably 20 to 40 degrees with emphasis on elongation in the hose axis direction, whereas if the cord angle is less than 35 degrees, the hose is not seated. 35 to 35
The code angle was set to 40 degrees.

The present invention is not limited to the above embodiment. For example, steel or nylon can be used as the fiber cord. Further, a ring-shaped rigid member can be used instead of the spiral wire 3a. Further, when applying the present invention to marine use,
A buoyancy material can be provided outside the reinforced rubber hose, and various other design changes can be made without changing the gist of the present invention. Test Destruction Test The reinforced rubber hose according to the example of FIG. 1, wherein the cord angle of the polyester cord of the main reinforcement layer 21 was 35 degrees and the coat angle of the polyester cord of the sub reinforcement layer 22 was 54 degrees 44 minutes. Was used to perform a destructive test with water pressure. The elongation of the reinforced rubber hose was 1.8% in a state where a constant working pressure of 1.55 MPa was applied to the reinforced rubber hose. In addition, 7.7 which is the design burst pressure is used.
The main reinforcing layer 21 was broken by a load of 8.6 MPa exceeding 5 MPa, but water was retained by the sub-reinforcing layer 22 and did not leak to the outside.

The elongation of the hose at the time of breaking is 14%.
Met. After the rupture, a decrease in water pressure was observed. Again, the elongation of the hose when it was raised to the normal operating pressure of 1.55 MPa was 5.1%, and the occurrence of this elongation detected the breakage of the main reinforcing layer 21. The disassembly inspection after the test confirmed that the peeling layer 20 at break had peeled over the entire hose. Bending and bending test Using a reinforced rubber hose similar to that used in the above-mentioned destruction test, 100,000 bending operations with a curvature having a bending radius of 6 times the inner diameter of the hose under a constant operating pressure of 1.55 MPa. Was made. In the disassembly inspection after the end of the test, no peeling occurred in the peeling layer 20 at break.

[0024]

As described above, according to the reinforced rubber hose of the present invention, when the main reinforcing layer breaks, the peeling layer can be peeled off at the time of breaking to prevent local internal pressure load on the sub reinforcing layer. The internal fluid can be reliably held by the sub-reinforcing layer, and leakage to the outside can be prevented. In addition, both the main reinforcing layer and the sub-reinforcing layer can efficiently contribute the fiber cord to the strength thereof, and thus can reduce the manufacturing cost without unnecessarily lengthening the fiber cord. Has the effect of

[Brief description of the drawings]

FIG. 1 is a schematic longitudinal sectional view of a reinforced rubber hose according to one embodiment of the present invention.

FIG. 2 is a schematic view showing an arrangement direction of fiber cords.

FIG. 3 is a schematic sectional view of a main part of a reinforced rubber hose including a release layer at break.

FIG. 4 is a schematic longitudinal sectional view of a conventional reinforced rubber hose.

[Explanation of symbols]

 Reference Signs List 1 inner rubber layer 2 outer rubber layer 3 intermediate rubber layer 3a spiral wire (rigid member) 20 peeling layer at break 21 main reinforcing layer 22 sub reinforcing layer C polyester cord (fiber cord) P hose axial direction

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-300590 (JP, A) JP-A-56-101485 (JP, A) JP-A-2-41786 (JP, U) JP-A-4-104 39487 (JP, U) JP 3-18077 (JP, B2) JP 55-229 (JP, B2) JP 3-29669 (JP, Y2) (58) Fields surveyed (Int. Cl. ⁷ , DB name) F16L 11/08 B32B 1/08 B32B 25/10

Claims (1)

(57) [Claims] 1. A method according to claim 1, wherein the inner rubber layer and the outer rubber layer have a tubular shape.
A reinforcing rubber hose in which a tubular reinforcing layer including a fiber cord is provided and an intermediate rubber layer in which a spiral or ring-shaped rigid member is embedded is provided. And a sub-reinforcing layer laminated on the outer peripheral side of the intermediate rubber layer. The fiber cord of the main reinforcing layer has a length of 35% with respect to the hose axial direction.
The fiber cord of the sub-reinforcing layer has a breaking strength due to extension in the hose axis direction and a breaking strength due to extension in the hose circumferential direction when the main reinforcing layer is broken. It is arranged at an angle of about 54 degrees 44 minutes with respect to the hose axis direction so as to be substantially equal. Between the intermediate rubber layer and the sub-reinforcement layer, the sub-reinforcement is performed over the entire length of the hose with the breakage of the main reinforcement layer A reinforced rubber hose, comprising a break-off release layer that causes separation to separate a layer from an inner peripheral portion thereof.