JP4946659B2 - Abnormality detection method for fiber reinforced plastic panel and fiber reinforced base material used in this abnormality detection method - Google Patents

Description

The present invention relates to a fiber reinforced plastic panel abnormality detection method and a fiber reinforced base material used in the abnormality detection method, which can easily detect abnormality inside the fiber reinforced plastic panel after being cured.

  In recent years, in the field of ships, large hulls have been made into fiber reinforced plastic (FRP) panels, and accordingly, large fiber reinforced plastic panels have become necessary. Various methods for producing resin molded products such as fiber reinforced plastic panels are known. However, the resin molding method using the autoclave method has restrictions on the size of the autoclave, so a sufficiently large fiber reinforced plastic panel must be produced. I can't.

  Therefore, development of fiber reinforced plastic panels by resin transfer molding method (RTM) or vacuum-assisted resin transfer molding method (VaRTM) that can be expected to improve quality and reduce costs as equipment has little size restrictions. Is underway. This vacuum resin transfer molding method (VaRTM) is extremely advantageous in that a large-sized resin molding can be easily molded in a room temperature process, and is applied to the manufacture of wind power generator blades (for example, Patent Document 1, 2).

In this manufacturing method, when impregnating the resin material on the mold with the laminate laminated with fiber reinforced base material, the impregnation status cannot be grasped visually with respect to the inside and the lower part of the laminate. In some cases, the determination of the impregnation state may be wrong, and the resin material may be cured in a state where the impregnation is insufficient, resulting in a void in the panel, resulting in a manufacturing defect. However, it is difficult to detect such abnormalities inside the panel after curing, and much man-hours and expensive equipment such as breaking the panel or performing ultrasonic inspection are required.
JP 2000-501659 A JP-T-2001-510748

The present invention, such conventional ones that have been proposed in view of problems, the main object, fiber-reinforced plastic panels to the abnormality of the interior of the fiber-reinforced plastic panels after curing can be easily detected It is an object of the present invention to provide a method for detecting an abnormality and a fiber-reinforced base material used in the abnormality detection method .

In order to achieve the above object, the fiber reinforced plastic panel abnormality detection method according to the present invention is a method in which a laminate obtained by laminating a fiber reinforced base material is impregnated with a resin material and then cured to form a conductive wire inside the fiber reinforced plastic panel. Are embedded in a non-contact state with each other, and both ends of the conductor wire are extended to the panel end surface. Among the plurality of conductor wires embedded in the fiber reinforced plastic panel, between the two selected conductor wires The gist is that the electric capacity or electric resistance is measured, and the presence or absence of voids in the fiber-reinforced plastic panel is detected based on the measurement result .

Here, for example, the conductive wires are embedded in a fiber-reinforced plastic panel in a lattice shape.

The fiber reinforced base material of the present invention is a fiber reinforced base material in which a plurality of laminated layers are impregnated with a resin material under negative pressure and then cured to form a fiber reinforced plastic panel. disposed conductors in a fiber woven fabric constituting the one in which the subject matter that both ends of the conductor line is extended to the end face of the fiber-reinforced plastic panels to the formation.

  Here, a plurality of the conductive wires can be arranged on the fiber fabric in a non-contact state with each other. At this time, the conductive wires may be arranged on the fiber fabric in a lattice shape.

The electrical capacitance or electrical resistance measured by the anomaly detection method of the present invention in which the electrical capacitance or electrical resistance between two selected electrical wires embedded in the fiber reinforced plastic panel is measured is a predetermined value. If it is larger, it can be easily determined that there is a gap inside the panel.

Further, according to the fiber reinforcement material of the present invention, by disposing the conductors in a fiber woven fabric constituting the fiber reinforcing substrate, are extended at both ends of the conductor wire to the end face of the fiber-reinforced plastic panels to the form since it is, when manufacturing a fiber-reinforced plastic panels, only stack as part of the laminate of the fiber-reinforced base material, after curing of the panel, the present invention in which a conductive wire that is disposed within the fiber fabric described above It can be used as a conductor for detecting an abnormality inside the panel by the abnormality detection method.

  Hereinafter, the present invention will be described based on the embodiments shown in the drawings.

As illustrated in FIGS. 1 and 2, the fiber reinforced plastic panel 1 used in the present invention is formed by curing a laminate 2 in which a plurality of fiber reinforced base materials 3 impregnated with a resin material W are laminated. Yes. Inside the fiber reinforced plastic panel 1, a plurality of conductive wires 4a to 4h are embedded in a lattice shape with their both ends extending to the panel end surface. These conducting wires 4a to 4h are not in contact with each other.

The number of the conductive wires 4 embedded in the fiber reinforced plastic panel 1 is plural, and both ends thereof are extended to the panel end surface. The mutual conducting wires 4 are brought into a non-contact state. As a material of the conducting wire 4, metal fibers such as carbon fiber, stainless steel fiber and copper fiber can be used.

  The fiber reinforced base material 3 is configured by a fiber fabric as illustrated in FIG. The fiber reinforced substrate 3 is made of organic fibers 5 such as polyester and aramid, or inorganic fibers 5 such as glass, and the conductors 4a to 4d are arranged in a non-contact state in the fiber fabric. A single conductor 4 may be disposed on one fiber-reinforced substrate 3, and when a plurality of conductors 4 are embedded, the conductors 4 are brought into a non-contact state. A plurality of conducting wires 4 may be arranged in a lattice shape.

  The fiber reinforced plastic panel 1 illustrated in FIG. 1 includes two fiber reinforced base materials 3 illustrated in FIG. 4 as conductors 4a to 4d and conductors with a fiber reinforced base material 3a having no conductive wires 4 interposed therebetween. 4e to 4h are stacked so as to be orthogonal to each other. A method for manufacturing the fiber reinforced plastic panel 1 will be described later.

  Next, the abnormality detection method for the fiber-reinforced plastic panel of the present invention will be described. As illustrated in FIG. 2, two conductors 4 a and 4 e are selected from among a plurality of conductors 4 embedded in the fiber reinforced plastic panel 1, and end portions of the conductors 4 a and 4 e positioned on the panel end surface are selected. , And connected to the measuring instrument 6 through a lead wire. The measuring device 6 measures the electric capacity between the conducting wires 4a and 4e, and the measurement result is displayed on the monitoring device 7. The measuring device 6 may measure the electrical resistance between the conducting wires 4a and 4e.

  When there is a gap between the two conducting wires 4a and 4e, the electric capacity and the electric resistance change as compared with a place where the resin material W is filled and there is no gap. Therefore, based on the result of the electric capacity or electric resistance measured by the measuring instrument 6, when the measured value is larger than a predetermined value, it can be determined that there is a gap. As predetermined values (reference electric capacity value, reference electric resistance value) serving as a determination criterion, a measured value at a healthy position without a gap may be used.

When the conducting wires 4 are arranged in a lattice shape, the position of the gap is more easily specified by sequentially changing the combination of the two conducting wires 4 for measuring electric capacity or electric resistance. be able to.
Next, an abnormality detection method as a reference form of the present invention will be described. As illustrated in FIG. 3, one conductor 4 a is selected from among a plurality of conductors 4 embedded in the fiber reinforced plastic panel 1, and both ends of the conductor 4 a positioned on the panel end surface are connected to lead wires. To the measuring device 6. The instrument 6 is for inspecting the presence or absence of energization of the conductors 4a, the inspection results are displayed on the monitoring device 7. An electric resistance meter (tester) can be used as the measuring device 6.

When the conducting wire 4a is not energized, it is considered that the conducting wire 4a is disconnected due to excessive deformation of the fiber reinforced plastic panel 1. Therefore, based on the result of the presence or absence of energization by the measuring instrument 6, it can be determined that there is damage such as deformation inside the fiber reinforced plastic panel 1 when no energization is performed.
In this way, abnormalities (such as voids and damage) inside the fiber reinforced plastic panel 1 after being cured can be easily detected without using an expensive device.

  Next, a method for producing a fiber reinforced plastic panel 1 using the fiber reinforced substrate 3 of the present invention will be described.

  As illustrated in FIG. 5, a laminate 2 in which a plurality of fiber reinforced base materials 3 and 3 a are laminated on a mold 8 is placed, and a resin flow path medium such as a continuous mat or a resin material is placed on the laminate 2. The supply tubes 9 for W (main agent, curing agent, accelerator) are arranged in order, and the whole is covered with the vacuum bag 10. Here, as illustrated in FIG. 1 and FIG. 2, the laminated body 2 interposes a fiber reinforced base material 3 a that does not have the conductive wire 4, and connects the two fiber reinforced base materials 3 and 3 to the respective conductive wires 4 a to 4. 4d and conductive wires 4e to 4h are formed so as to be orthogonal to each other.

  Lead wires 4a to 4h are extended on the outer peripheral side of the mold 8, and the periphery of the vacuum bag 10 is hermetically fixed on the mold 8 with a sealing tape. A suction pipe 11 connected to a pump is disposed in the vicinity of the lower portion of the laminate 2.

  Then, the resin material W is supplied to the inside of the vacuum bag 10 through the supply tube 9 while sucking the air inside the vacuum bag 10 through the suction pipe 11. As a result, the resin material W is discharged from the inside of the vacuum bag 10 to the outside through the suction pipe 11, and at the same time, the laminate 2 is impregnated with the resin material W.

  Next, the laminate 2 impregnated with the resin material W is cured. Conductive wires 4a to 4h extending from the laminate 2 are cut at the end face of the laminate 2 (panel). Thereby, the fiber reinforced plastic panel 1 of the present invention is manufactured.

  As described above, when the fiber reinforced base material 3 of the present invention is used, when the fiber reinforced plastic panel 1 is manufactured, the fiber reinforced plastic panel 1 is simply laminated as a part of the laminated body 2 and disposed on the fiber fabric after the panel is cured. The conducting wire 4 can be used as the conducting wire 4 for detecting an abnormality inside the panel.

  In addition, when the fiber reinforced plastic panel 1 is manufactured, the conductive wire 4 serves as an electric capacitance sensor for monitoring whether or not the resin material W is uniformly impregnated from the upper layer to the lower layer of the laminate 2. Can also be used.

  When the resin material W reaches the position where the conducting wire 4 is arranged in the impregnation process, the electric capacity value between the conducting wires 4 changes. Therefore, the selected two conducting wires 4 are connected to the measuring device 6 via the lead wires, and the electric capacity between the conducting wires 4 measured by the measuring device 6 is monitored by the monitoring device 7, whereby the laminate of the resin material W is obtained. 4 can be ascertained. For example, when the measured electric capacity value is larger than a preset reference value, it is determined that the resin material W is impregnated in the laminate 2 at the position where the conducting wire 4 is disposed.

  As a result, since the impregnation state of the resin material W can be reliably grasped even inside or under the laminate 2 that cannot be visually observed, the laminate 2 in a state where the impregnation of the resin material W is insufficient is cured. Such manufacturing defects can be prevented. Therefore, the fiber reinforced plastic panel 1 having high accuracy and excellent quality can be manufactured.

  When the conducting wires 4 are arranged in a grid, it is possible to easily specify the position where the impregnation is insufficient by sequentially changing the combination of the two conducting wires 4 for measuring the electric capacity. it can.

It is an internal perspective view which illustrates the fiber reinforced plastic panel used for this invention. It is explanatory drawing which illustrates the abnormality detection method of this invention using the fiber reinforced plastic panel of FIG. It is explanatory drawing which illustrates the abnormality detection method used as the reference form of this invention. It is a perspective view which illustrates the fiber reinforced base material of this invention. With fibrous reinforcing substrate of FIG. 4 is an explanatory diagram illustrating a method of manufacturing a fiber-reinforced plastic panels for use in the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fiber reinforced plastic panel 2 Laminated body 3 Fiber reinforced base material 3a Fiber reinforced base material which does not have conducting wire 4, 4a, 4b, 4c, 4d, 4e, 4f, 4g, 4h Conducting wire 5 Fiber 6 Measuring instrument 7 Monitoring apparatus 8 Mold 9 Supply tube 10 Vacuum bag 11 Suction pipe W Resin material

Claims (5)

After impregnating a resin material into a laminated body in which fiber reinforced base materials are laminated, a plurality of conductive wires are embedded in a fiber reinforced plastic panel formed by curing, and both ends of the conductive wires are embedded in a non-contact state. The electrical capacity or electrical resistance between the two selected conductors extending from the panel end face and embedded in the fiber reinforced plastic panel is measured, and the fiber reinforced plastic panel is measured based on the measurement result. An abnormality detection method for a fiber-reinforced plastic panel that detects the presence or absence of voids. The abnormality detection method for a fiber reinforced plastic panel according to claim 1 , wherein the conductive wires are embedded in a fiber reinforced plastic panel in a lattice shape. Distribution after the resin material is impregnated in the negative pressure in the stacked state, the fiber-reinforced base material to form a fiber-reinforced plastic panels by curing a conducting wire into the woven fabric constituting the fibrous reinforcing substrate And a fiber reinforced base material in which both ends of the conducting wire are extended to the end face of the fiber reinforced plastic panel to be formed. The fiber reinforced base material according to claim 3 , wherein a plurality of the conductive wires are arranged on a fiber fabric in a non-contact state with each other. The fiber-reinforced base material according to claim 4 , wherein the conductive wires are arranged in a fiber fabric in a lattice shape.

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