JP2010138991A - Method of detecting damage of hose, and abrasion resistant hose - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently detect abrasions and damages on an inner circumferential face and an outer circumferential face of a hose, in the hose required to detect the abrasions and the damages of the hose such as a mortar forcibly feed hose. <P>SOLUTION: The damages on the inner circumferential face and the outer circumferential face of the hose (1) are electrically detected at the same time, by connecting a conductor (21) embedded spirally in an inner circumferential face side of the hose (1), and a conductor (22) embedded spirally in an outer circumferential face side of the hose, in series, and by examining a conductive state of the connected conductors. The conductor (21) embedded spirally in the inner circumferential face side of the hose is preferably embedded just under side of a hose hardness reinforcing body (11), or preferably embedded in the substantially central position between the hardness reinforcing bodies (11). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a wear-resistant hose that allows a fluid that wears the hose wall, such as powder and mortar, to flow inside the hose, and in particular, damage (abrasion or breakage) of the hose wall to accurately determine the life of the hose. It is related with the method of detecting.

In the case of hoses used for the transportation of slurry such as cement, mortar, and earth, and the transportation of powder such as slaked lime, the fluid flowing through the hose wears the hose wall. An improved hose is used. However, even with wear-resistant hoses, with use, the inner layer of the hose gradually wears out, eventually reaching the life of the hose.

If these hoses reach the end of their service life, the hoses will break (burst) and the mortar inside will erupt and contaminate the surroundings. The life of the hose is determined and the hose is replaced early.

As a technique for detecting the wear on the inner surface of the hose, there is a technique described in Patent Document 1, in which a pair of conductive wires are embedded in a spiral shape outside the inner layer of the hose over the entire length of the hose. A pair of conductors are connected to each other at one hose end, and a tester is connected to the other pair of conductors at the other hose end to detect the conductive state of the conductor, thereby preventing wear on the inner layer of the hose (electrically breaking the conductor). Detection is described (by detection).

Patent Document 2 relates to a technique for detecting wear on the outer surface of the hose when dragged during use of the hose, and a wear display layer made of a material having a color different from that of the outer skin layer is provided inside the outer skin layer of the hose. A pressure-resistant hose is described, and according to the hose, since the wear display layer is exposed when the outer skin layer is worn, it is described that the wear of the outer skin layer can be detected visually.
JP-A-8-270844 Japanese Utility Model Publication No. 62-181779

However, if it is attempted to detect hose wear or damage by visual inspection, it is necessary to perform visual inspection over the entire length and circumference of the hose, which requires time and labor for inspection, and depending on the usage of the hose, visual inspection is difficult. Since a part may arise, a wear detection method other than visual inspection has been desired.

Further, if the technique described in Patent Document 1 is used, wear on the inner surface of the hose can be detected efficiently, but in order to detect wear or breakage on the outer surface of the hose, a detection means such as a sensor is separately provided or a visual inspection is performed. It must be relied on, and the efficiency of detecting hose damage is reduced.

An object of the present invention is to make it possible to efficiently detect the wear and breakage of the inner and outer peripheral surfaces of the hose in these hoses that need to detect the wear and breakage of the hose.

As a result of intensive studies, the inventor spirally embeds the conductive wire on the inner peripheral surface side of the hose, embeds the conductive wire spirally on the outer peripheral surface side of the hose, and electrically connects both the conductive wires in series. It was found that the state of damage on the inner peripheral surface and the outer peripheral surface of the hose can be detected simultaneously when connected to a tester and the conduction state was confirmed, and the present invention was completed.

The present invention is a method for electrically detecting damage to an inner peripheral surface and an outer peripheral surface of a hose, a conductive wire embedded in a spiral shape on the inner peripheral surface side of the hose, and a spiral shape on the outer peripheral surface side of the hose. This is a method of simultaneously detecting damage to the inner peripheral surface and the outer peripheral surface of the hose by connecting the embedded conductive wires in series with each other and examining the conduction state of the connected conductive wires.

In the present invention, a hard reinforcement body made of a relatively hard resin material is spirally integrated on the outer peripheral surface side of the hose wall made of a relatively soft resin material. It is preferable that the conductive wire embedded is embedded at a position directly below the hard reinforcing body in the hose axial direction, and the conductive wire embedded on the outer peripheral surface side of the hose is a hose embedded inside the hard reinforcing body. ). Alternatively, in the present invention, a hard reinforcement body made of a relatively hard resin material is spirally integrated on the outer peripheral surface side of the hose wall made of a relatively soft resin material, and the hose is connected to the inner peripheral surface side of the hose. It is preferable that the hose is embedded at a position where the embedded conductive wire is located approximately at the center between the adjacent rigid reinforcing bodies in the hose axial direction.

According to the present invention, it is possible to simultaneously detect the wear and breakage of the inner peripheral surface and the outer peripheral surface of the hose, and to efficiently check the hose damage.

Further, in the present invention, if the arrangement of the conductors is arranged inside the hard reinforcing body or directly below the hard reinforcing body (Claim 2), the conductor is prevented from being damaged during the wiring work of the conductor, The efficiency of damage confirmation work is further increased.

Further, in the present invention, if the arrangement of the conductive wire on the inner peripheral surface side of the hose is set at the approximate center between the hard reinforcing bodies (Claim 3), the hose is molded in a state where the hose wall is bent inwardly, or When used, the detection of wear on the inner surface of the hose wall is improved.

Embodiments of the present invention will be described below. FIG. 1 is a partial cross-sectional view showing the structure of an abrasion resistant hose 1 used in the present invention. The wear-resistant hose 1 includes an inner layer 13 that is a soft layer constituting an inner peripheral surface of the hose, a reinforcing fiber layer 15 provided outside the inner layer 13, and an outer layer 12 that is a soft layer provided outside the reinforcing fiber layer 15. Is a hose having a flexible hose wall laminated and integrated with each other, and on the outer side of the outer layer 12, a helical reinforcing string 11 having an elliptical cross section made of a hard resin is embedded in the outer layer 12 approximately half. It is wound and integrated into a shape. The inner layer 13, the outer layer 12, and the hard reinforcing body 11 are integrated by being welded or vulcanized. The reinforcing fiber layer 15 is a layer formed by winding a plurality of thread-like / cord-like fiber bodies on the outer periphery of the inner layer 13 so as to form a net shape, and each fiber body is between the inner layer 13 and the outer layer 12. Embedded in an integrated state.

Furthermore, in this invention, the 1st conducting wire 21 is embed | buried and integrated in the inside of the inner layer 13 helically along a hose wall. Further, the hard reinforcing body 11 is provided with a slit S extending from the outermost peripheral portion of the hose toward the central portion of the reinforcing body along the longitudinal direction of the reinforcing body 11. Two conducting wires 22 are embedded in a spiral shape. Therefore, in the wear resistant hose 1 according to the present invention, the first conductive wire 21 is spirally embedded in a portion close to the inner peripheral surface of the hose and the second conductive wire 22 is close to the outer peripheral surface of the hose over the entire length of the hose. It is buried in a spiral in the part.

The inner layer 13 and the outer layer 12 are each a soft layer made of flexible rubber, synthetic resin, or the like. In this embodiment, the inner layer 13 is made of soft rubber, and the outer layer 12 is made of soft vinyl chloride resin. Has been. The resin material forming these layers is not particularly limited, and may be selected from rubbers, thermoplastic resins, thermoplastic elastomers, thermosetting resins, and the like having appropriate flexibility. In particular, it is preferable to use a material having excellent wear resistance in order to improve the durability of the wear resistant hose. Moreover, it is preferable that the resin material used for the layer which embeds a conducting wire uses a non-conductive, ie, insulating resin material from a viewpoint of improving the conduction | electrical_connection detection property of conducting wire. Moreover, it is preferable to comprise the resin material which comprises the inner layer 13 and the outer layer 12 by the material which can be welded or vulcanized-bonded mutually. Further, both may be bonded and integrated with an adhesive.

The hard reinforcing body 11 is made of a resin harder than the soft resin material forming the inner layer 13 and the outer layer 12, and is provided to prevent the hose 1 from being crushed or deformed. In the present embodiment, the hard reinforcing body 11 is formed of a hard vinyl chloride resin. The slit S of the hard reinforcing body 11 is formed by a manufacturing method to be described later, but the slit portion may be in a non-adhered state, weakly bonded, or completely welded and integrated. May be. It is more preferable for the slit portion to be non-adhered or weakly bonded in order to easily pull out the second conductive wire 22 and facilitate the connecting operation of the conductive wire.

As the conductive wire constituting the first conductive wire 21 and the second conductive wire 22, a wire-like fiber assembly including a metal wire such as a copper wire, a stranded wire of a metal wire, a conductive fiber such as carbon fiber, or a synthetic fiber Although a fiber-like fiber assembly including conductive fibers obtained by subjecting the fibers to copper plating or the like can be used, the conductive fibers obtained by subjecting the synthetic fibers to copper plating or the like so as to be easily cut along with the wear of the inner layer 13 or the hard reinforcement body 11. It is preferable to use a fiber assembly containing a conductive fiber. Moreover, it is preferable that the conductive wire is appropriately stretchable so that the conductive wire is not broken by bending or expansion / contraction of the hose.

The reinforcing fiber layer 15 is a layer made of a filamentous fiber body (cord) embedded and integrated in the hose in order to improve the pressure resistance and sag resistance of the hose, but as a fiber body constituting the reinforcing fiber layer Can use various synthetic fiber cords (thread-like fiber aggregates in which monofilaments or a plurality of synthetic fibers are bundled), and those made of fiber aggregates including polyester fibers, vinylon fibers, aramid fibers and the like are particularly preferable. The form of embedding the reinforcing fiber body is not limited to the above form. For example, the reinforcing fiber body may be embedded in a spiral shape or along the hose axial direction. Further, depending on the pressure resistance requirement required for the hose, the reinforcing fiber layer may not be provided.

A method for manufacturing the wear-resistant hose 1 will be described. The wear-resistant hose 1 supplies a resin material constituting each layer of the hose in a tape shape on a known hose molding shaft, and forms each layer by winding on the hose molding shaft, and sequentially stacks and integrates the layers. The so-called spiral molding method can be used.

That is, as shown in FIG. 2A, uncrosslinked rubber to form the inner layer 13 is extruded in a tape shape with a substantially parallelogram-shaped cross section (T1), and spirally wound on the hose forming shaft (Q). The inner layer 13 is formed by turning and integrating adjacent side edges of the tape. Crosslinking of the uncrosslinked rubber is performed by heating the hose forming shaft. Further, when the tape T1 is spirally wound, the first conductive wire 21 is supplied to the overlapping portion of both side edges and wound in the same spiral manner, and the first conductive wire 21 is embedded in the inner layer 13 Integrate. Further, a reinforcing fiber layer 15 is formed by winding a reinforcing thread (reinforcing cord) around the outer surface of the inner layer 13 in a portion where the inner layer 13 in which the conductive wire 21 is embedded is formed.

Subsequently, as shown in FIG. 2 (b), the hard vinyl chloride resin constituting the hard reinforcing body 11 is extruded in a string shape in a semi-molten state so that the hose outer surface side has an open circular cross section (R1), The soft vinyl chloride resin forming the outer layer 12 is extruded into a tape shape having a deformed parallelogram cross section in a semi-molten state (T2). These extrusions are performed by co-extrusion, and as shown in the drawing, the two layers are spirally wound around the outer periphery of the inner layer 13 and the reinforcing fiber layer 15 formed in advance. Both side edges of the tape T2 are overlapped with each other and integrated by fusion to form the outer layer 12. A portion of the hard vinyl chloride resin R1 extruded into a deformed circular cross section that is open toward the outer surface of the hose is supplied with a second conductive wire 22 and spirally wound. As a result of the pressure being applied, the open portion is closed and the slit S is brought into close contact, and the second conductor 22 is embedded and integrated in the hard reinforcing body 11. With the inner layer 13, the reinforcing fiber layer 15, the outer layer 12, and the hard reinforcing body 11 laminated and integrated, the hose is cooled from the outer surface side of the hose to harden the hard vinyl chloride resin or the soft vinyl chloride resin, and wear resistance The continuous hose 1 is manufactured continuously.

As will be described with reference to FIG. 3, according to the damage detection method of the present invention, damage to the inner peripheral surface and the outer peripheral surface of the wear-resistant hose 1 can be detected simultaneously by electrical means.
When the wear-resistant hose 1 is used, the end of the hose is connected to a flange, a connector, a coupler (not shown) or the like. At this time, the first conductor 21 and the second conductor are connected from the end of the hose. 22, the first conductor 21 and the second conductor 22 are electrically connected to each other at one end of the hose, and the first conductor 21 and the second conductor 22 are connected to each other at the other end. The tester device T is connected to the input terminal. That is, the first conductive wire 21 spirally embedded and integrated on the inner peripheral side of the hose and the second conductive wire 22 spirally embedded and integrated on the outer peripheral side of the hose are electrically connected to the tester T in series. So that

When the hose is dragged, the hard reinforcing body 11 is damaged (wear, breakage, etc.), the second conductor 22 is broken, or the hose inner peripheral surface damage (wear, breakage, etc.) proceeds. When the first conductor 21 is disconnected, in any case, a disconnection occurs in the circuit in which the first conductor 21 and the second conductor are connected in series. For example, it is possible to determine whether the inner peripheral surface and the outer peripheral surface are not seriously damaged, or whether one of them is damaged and the hose needs to be replaced by a single check operation. That is, according to this method, the presence or absence of damage to the inner peripheral surface and the outer peripheral surface of the hose can be detected simultaneously using one tester device. Note that the confirmation of the conduction state by the tester may be performed temporarily, for example, during a periodic inspection of the hose, or the damage state of the hose may be constantly monitored by connecting the tester T to the conductor.

The tester device T only needs to be able to measure and display the conduction state and conduction resistance of the conductor to such an extent that the presence or absence of disconnection or disconnection of the conductor can be determined. It may be a light emitter.

As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment, It can implement by carrying out various modifications. Other embodiments of the present invention will be described below. However, in the following description, portions different from the above-described embodiment will be mainly described, and descriptions of the same portions will be omitted.

FIG. 4 shows an abrasion resistant hose 2 used in the second embodiment of the present invention. In the wear-resistant hose 2, the two first conductors 21 a and 21 b are embedded and integrated into the inner layer 13 in two spirals, and the two hard reinforcing bodies 11 and 11 are near the outer surface of the outer layer 12. In the vicinity of the outer peripheral surface of the outer layer 11, two second conductors 22 a and 22 b are embedded and integrated so as to be sandwiched between the hard reinforcing bodies 11 and 11 in two spirals. Yes.

As described above, the number of conductive wires to be embedded can be changed as appropriate to implement the present invention, and the configuration of the outer layer of the hose and the hard reinforcement used in the present invention can be changed as appropriate. In short, in the hose used in the present invention, it is only necessary that the first conductor and the second conductor are embedded in portions where damage (wear and breakage) of the hose outer peripheral surface and the hose inner peripheral surface can be detected, respectively. . In addition, the hose used in the present invention is not limited to the wear-resistant hose, and the present invention can be applied to any hose in which conductive wires are embedded near the inner peripheral surface and the outer peripheral surface of the hose wall. is there.

When using a hose in which two conductors are embedded on the inner peripheral surface side and the outer peripheral surface side, such as the wear-resistant hose 2, it may be connected to the tester T as follows. That is, on one end side of the hose, the first conductors 21a and 21b are connected to each other, and the second conductors 22a and 22b are connected to each other. Further, on the other end side of the hose, the first conducting wire 21a and the second conducting wire 22a are connected, while the remaining first conducting wire 21b and the second conducting wire 22b are connected to the connection terminal of the tester T. With the above connection, all the conductive wires are wired in series to the tester. Therefore, even if any of the conductors is disconnected, it is possible to detect that one of the conductors is disconnected by confirming the conduction state of the circuit with one tester T. In the confirmation work, it can be confirmed whether the conductor is broken or not, and whether the hose is damaged can be detected.

In addition, regarding the embedment position in the hose axial direction when embedding the first conductive wire 21 embedded in the inner layer 13, as shown in FIGS. 1 and 4, the first conductive wire 21 is connected to the hard reinforcing body 11. And it is preferable to embed so that it may become a position which overlaps in a hose axial direction seeing from a hose radial direction, ie, it may be directly under the hard reinforcement body 11. FIG. By embedding the first conducting wire 21 in such a position, when the hose wall portion is cut open with a knife or the like along the hard reinforcement body so as to draw out the first conducting wire from the end portion of the hose, the first conducting wire 21 is used. It is possible to prevent the conductor 21 from being cut, and to simplify the processing of the conductor at the end of the hose. For the same reason, the second conductive wire 22 is preferably embedded in the hard reinforcing body 11 as shown in the wear resistant hose 1 of FIG.

Moreover, like the hose 3 of the form as shown in FIG. 5, the 1st conducting wire 21 embed | buried on the inner peripheral surface side of the hose wall 16 is between the rigid reinforcement bodies 11 regarding the position of a hose axial direction, In particular, it is preferable to embed at a position that is approximately the center of the adjacent hard reinforcing bodies. If a negative pressure is applied to the hose when it is used, or if the hose is bent, the hose wall will be deformed inwardly as shown in Fig. 5 and the inner surface of the hose will wear out. Although it becomes easy to generate | occur | produce and progress in the part which became the pleat, if the 1st conducting wire 21 is embed | buried in the position used as the approximate center of an adjacent hard reinforcement body, the conducting wire 21 will be arrange | positioned in the inner pleat part. As a result, it is possible to further improve the detection of wear and damage on the inner peripheral surface of the hose. In addition, as shown in FIG. 5, you may form a hose beforehand so that a hose wall may become what was formed in the inner pleat shape.

According to the hose damage detection method of the present invention, the wear and breakage of the inner peripheral surface and the outer peripheral surface of the hose can be detected simultaneously by electrical means. Therefore, the hose damage check operation is made more efficient and the industrial utility value is high.

It is a fragmentary sectional view which shows the structure of the abrasion-resistant hose used for this invention. It is a schematic diagram which shows the manufacturing process of an abrasion-resistant hose. It is a schematic diagram which shows the hose damage detection method of this invention. It is a schematic diagram which shows the hose damage detection method of this invention at the time of using the hose of another structure. It is a fragmentary sectional view which shows the other structure of the hose used for this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Abrasion-resistant hose 11 Hard reinforcement body 12 Outer layer 13 Inner layer 15 Reinforcing fiber layer 21 First conductor 22 Second conductor T Tester device

Claims (3)

A method for electrically detecting damage to the inner and outer peripheral surfaces of the hose,
By connecting the conductive wire spirally embedded on the inner peripheral surface side of the hose and the conductive wire embedded spirally on the outer peripheral surface side of the hose in series with each other, and examining the conduction state of the connected conductive wire, A method of simultaneously detecting damage to the inner and outer peripheral surfaces of the hose. A hose is spirally integrated with a hard reinforcement body made of a relatively hard resin material on the outer peripheral surface side of a hose wall made of a relatively soft resin material, and the lead wire embedded on the inner peripheral surface side of the hose is a hose shaft. The hose damage according to claim 1, wherein the hose is embedded in a position directly below the hard reinforcing body in a direction, and the conductive wire embedded on the outer peripheral surface side of the hose is embedded in the inside of the hard reinforcing body. Detection method. A hose is spirally integrated with a hard reinforcement body made of a relatively hard resin material on the outer peripheral surface side of a hose wall made of a relatively soft resin material, and the lead wire embedded on the inner peripheral surface side of the hose is a hose shaft. The hose damage detection method according to claim 1, wherein the hose is embedded in a position that is substantially in the middle between adjacent hard reinforcement bodies in the direction.

Images