JP6133707B2 - High pressure tank inspection method, high pressure tank inspection system, and high pressure tank - Google Patents

Description

  The present invention relates to a high-pressure tank.

  As a fuel gas tank for storing fuel gas (hydrogen) supplied to the fuel cell of a fuel cell vehicle, a reinforcing fiber impregnated with a thermosetting resin such as epoxy resin is wound around the outer periphery of the tank container, and its thermosetting property Development of a high-pressure tank in which a fiber reinforced resin layer is formed by thermosetting a resin has been underway.

  The high-pressure tank mounted on the fuel cell vehicle may be deformed by an external impact (for example, a compressive impact load) due to road surface interference or the like, and its strength may be reduced. It is not preferable to use a high-pressure tank as it may decrease in strength. For this reason, it is desirable to detect the state of the high-pressure tank in real time and replace the high-pressure tank whose strength may be lowered at an early stage. The “high-pressure tank whose strength may be reduced” includes a high-pressure tank whose strength is reduced.

  Conventionally, as a technique for detecting deformation of a high-pressure tank, as described in Patent Document 1, a conductive layer whose resistance value changes corresponding to the deformation of the high-pressure tank has been provided outside the high-pressure tank. A technique for detecting in real time the deformation of the high-pressure tank by a change in the resistance value detected by the conductive layer is disclosed.

JP2011-185426A

  However, in the high-pressure tank in which the fiber reinforced resin layer is formed, even if the deformation amount (for example, the dent amount) on the surface is the same, the degree of strength reduction inside the fiber reinforced resin layer is not the same, and the strength reduction is May be larger. When the decrease in strength inside the fiber reinforced resin layer is large, peeling between the fiber reinforced resin layers in the fiber reinforced resin layer (hereinafter also referred to as “interlayer peeling”) is deep inside the fiber reinforced resin layer. It may have occurred up to. For this reason, the amount of deformation on the surface of the high-pressure tank alone cannot detect the influence of peeling occurring inside the fiber-reinforced resin layer, and is not sufficient as an inspection method for the high-pressure tank in which the fiber-reinforced resin layer is formed. There are challenges.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms.

(1) According to one form of this invention, the inspection method of the high pressure tank which test | inspects the state of the high pressure tank in which the fiber reinforced resin layer was formed in the outer periphery of a tank container is provided. The high-pressure tank has a cylindrical cylinder part and dome parts on both sides of the cylinder part. A signal that changes depending on the state of delamination in the fiber reinforced resin layer on the outer peripheral surface or the inner peripheral surface of the tank shoulder toward the tip of the dome portion from the boundary between the cylinder portion and the dome portion. Install one or more peeling state detection sensors to output. Based on the signal output from the peeling state detection sensor, it is determined whether the delamination exists in the fiber reinforced resin layer in the tank shoulder. According to the high pressure tank inspection method of this aspect, it is possible to determine the state of delamination in the fiber reinforced resin layer in the tank shoulder of the high pressure tank in which the fiber reinforced resin layer is formed on the outer periphery of the tank container. As a result, the state of the high-pressure tank can be detected in real time, and the high-pressure tank whose strength may be reduced can be replaced at an early stage.

(2) In the inspection method for a high-pressure tank according to the above aspect, when the delamination exists, the delamination of the fiber reinforced resin layer in the depth direction is performed based on a signal output from the delamination state detection sensor. The position may be obtained, and it may be determined whether or not the delamination exists in the shoulder inner layer region on the inner layer side of the fiber reinforced resin layer. According to the inspection method for a high-pressure tank of this embodiment, it can be determined whether or not delamination has occurred in the shoulder inner layer region on the inner layer side of the fiber reinforced resin layer. As a result, it is possible to detect the state of the high-pressure tank in real time and replace the high-pressure tank whose strength may be lowered at an early stage.

(3) In the inspection method for a high-pressure tank according to the above aspect, a plurality of peeling state detection sensors are installed along at least the circumferential direction of the outer peripheral surface or inner peripheral surface of the tank shoulder, and the delamination exists. In this case, the delamination position in the direction along the surface of the tank shoulder may be obtained based on a plurality of signals output from the plurality of peeling state detection sensors. According to the high pressure tank inspection method of this aspect, the delamination position in the direction along the surface of the tank shoulder can be obtained.

  The present invention can be realized in various forms other than those described above. For example, the present invention can be realized in forms such as a high-pressure tank inspection system, a high-pressure tank, a fuel cell system, and a fuel cell vehicle.

It is explanatory drawing which shows the inspection system of the high pressure tank as 1st Embodiment. It is explanatory drawing shown about the problem when delamination occurs in the inside of the fiber reinforced resin layer of a tank shoulder part. It is explanatory drawing which shows the detection flow of the delamination of the fiber reinforced resin layer of a tank shoulder part. It is a graph which shows an example of the sensor output signal output from a peeling state detection sensor. It is explanatory drawing which shows the test | inspection system of the high pressure tank as a modification of 1st Embodiment. It is explanatory drawing which shows the inspection system of the high pressure tank as 2nd Embodiment. It is explanatory drawing which shows the test | inspection system of the high pressure tank as a modification of 2nd Embodiment. It is explanatory drawing which shows the inspection system of the high pressure tank as 3rd Embodiment. It is explanatory drawing which shows the inspection system of the high pressure tank as 4th Embodiment. It is a graph which shows an example of the relationship between the tank internal pressure and distortion amount when there is no delamination. It is a graph which shows an example of the relationship between the position of the depth direction in which the delamination has generate | occur | produced using several tank internal pressure as a parameter, and distortion amount. It is explanatory drawing which shows the inspection system of the high pressure tank as 5th Embodiment.

A. First embodiment:
FIG. 1 is an explanatory diagram illustrating a high-pressure tank inspection system according to a first embodiment. FIG. 1B schematically shows an inspection system 1000. However, for the high-pressure tank 100 to be inspected, a schematic cross section taken along a plane parallel to the tank axis CX (cross section AA in FIG. 1A) is schematically shown. FIG. 1A schematically shows the left side surface in the direction along the tank axis CX of the high-pressure tank 100 of FIG.

  The high-pressure tank 100 is, for example, a pressure vessel that is mounted on a fuel cell vehicle (not shown) and stores high-pressure hydrogen supplied as fuel gas to the fuel cell. The high-pressure tank 100 includes a liner 10, a fiber reinforced resin layer 20, a valve side base 30, an end side base 40, and a plug 50.

  The liner 10 is a hollow tank container made of a resin such as metal or reinforced plastic, and includes a cylindrical cylinder portion 11 and substantially hemispherical dome portions 12 on both sides of the cylinder portion 11. A valve side cap 30 having a plug connection hole centered on the tank axis CX is provided at the top of one dome portion 12 (left side of FIG. 1B), and the other dome portion 12 (FIG. 1). An end-side base 40 for closing the end side of the liner 10 is provided at the top portion (right side of (B)). A plug 50 is inserted and connected to the plug connection hole of the valve side cap 30. A fuel cell and a gas filling unit are connected to the high-pressure tank 100 via a pipe (not shown) connected to the plug 50, and charging and discharging of high-pressure fuel gas (hereinafter also simply referred to as “high-pressure gas”). Is done.

  The fiber reinforced resin layer 20 is a reinforcing layer that covers the outer surface of the liner 10 and the periphery of the valve side cap 30 and the end side cap 40 (hereinafter referred to as “the outer surface of the liner 10 and the like”). The fiber reinforced resin layer 20 is composed of a reinforced fiber such as carbon-fiber-reinforced plastic (CFRP) wound around the outer surface of the liner 10 and heat such as an epoxy resin that binds the reinforced fibers. And a curable resin. The fiber reinforced resin layer 20 is formed as follows, for example. First, the reinforcing fiber impregnated with the thermosetting resin is wound so as to cover the outer surface and the like of the liner 10 by a predetermined winding method such as so-called helical winding or hoop winding. Next, the liner 10 around which the reinforcing fibers are wound is heated at a predetermined temperature in a thermostatic bath, and the thermosetting resin in the reinforcing fibers is thermoset. As a result, the fiber reinforced resin layer 20 is formed on the outer surface of the liner 10 or the like.

  A portion 102 of the high-pressure tank 100 in which the fiber reinforced resin layer 20 is formed so as to cover the outer surface of the cylinder portion 11 of the liner 10 corresponds to the cylinder portion of the high-pressure tank 100. Hereinafter, this portion 102 is referred to as “cylinder portion 102” of the high-pressure tank 100. A portion 104 b of the high-pressure tank 100 in which the fiber reinforced resin layer 20 is formed so as to cover the outer surface of the valve-side dome portion 12 of the liner 10 and the outer peripheral surface of the valve-side base 30 is provided on the valve side of the high-pressure tank 100. Corresponds to the dome. Hereinafter, this portion 104b is referred to as a “dome portion 104b” on the valve side of the high-pressure tank 100. Similarly, the portion 104 e of the high-pressure tank 100 in which the fiber reinforced resin layer 20 is formed so as to cover the outer surface of the dome portion 12 on the end side of the liner 10 and the outer peripheral surface of the end-side base 40 is the end side of the high-pressure tank 100. Corresponds to the dome part. Hereinafter, this portion 104e is referred to as the “dome portion 104e” on the end side of the high-pressure tank 100. In addition, when the dome portion 104b on the valve side and the dome portion 104e on the end side are not particularly distinguished, these are also simply referred to as “dome portion 104”.

  The inspection system 1000 is mounted on a fuel cell vehicle in the same manner as the high pressure tank 100, and inspects the state of the high pressure tank 100 in real time during the operation of the fuel cell vehicle. The inspection system 1000 includes a peeling state detection sensor 110 installed on the outer peripheral surface of the tank shoulder 106 of the high-pressure tank 100, an acceleration sensor 130 installed in the fuel cell vehicle, and a determination unit 120.

  The tank shoulder portion 106 of the high-pressure tank 100 is a portion from the boundary between the cylinder portion 102 and the dome portion 104 toward the tip of the dome portion 104, from the boundary between the cylinder portion 102 and the dome portion 104 to the tip of the dome portion 104. It is defined as a portion within 50% of the height Ld. However, the range may be ± 10% of Ld / 2. In addition, a portion 24 having a thickness of 50% or less on the inner layer side of the fiber reinforced resin layer 20 existing inside the tank shoulder portion 106 is defined as a “shoulder inner layer region”. However, it may be in the range of 50% ± 10% of the thickness of the fiber reinforced resin layer 20.

  The peeling state detection sensor 110 is a sensor for detecting delamination in the fiber reinforced resin layer 20 of the tank shoulder portion 106. In this example, the peeling state detection sensor 110 includes an ultrasonic transmitter and receiver. Since the ultrasonic wave output from the transmitter and propagating through the fiber reinforced resin layer 20 is reflected at the interface between the resin layer and the air layer, the ultrasonic wave received by the receiver changes according to delamination. The peeling state detection sensor 110 uses this phenomenon to detect the occurrence of delamination. In addition, as the peeling state detection sensor 110, it is preferable to use an ultrasonic sensor in which the ultrasonic wave output from the transmitter is a Lamb wave.

  The acceleration sensor 130 is a sensor for detecting that an impact due to a compression impact load or the like is applied to the high-pressure tank 100 due to road surface interference or the like during the driving operation of the fuel cell vehicle. As the acceleration sensor 130, a three-dimensional acceleration sensor is generally used.

  As will be described later, the determination unit 120 determines whether or not delamination has occurred based on an output signal from the peeling state detection sensor 110.

  FIG. 2 is an explanatory diagram showing a problem when delamination occurs in the fiber reinforced resin layer 20 of the tank shoulder 106. When an impact due to a compressive impact load or the like is applied to the high-pressure tank 100 due to road surface interference or the like during the driving operation of the fuel cell vehicle, as shown in FIG. 2 (A), the tank shoulder 106 has an inside of the fiber reinforced resin layer 20. One or more delaminations may occur. Even if this delamination is a small delamination at the time of occurrence, as shown in FIG. 2B, when filling and releasing high-pressure gas repeatedly during the operation, the stress corresponding to this May be added to the delamination portion of the fiber reinforced resin layer 20 through the liner 10 (dome portion 12), and may grow into a large delamination.

  When large delamination occurs in the shoulder inner layer region 24 of the tank shoulder 106, stress is applied only to the portion of the fiber reinforced resin further on the inner layer side than the generated delamination. When the applied stress exceeds the strength limit, as shown in FIG. 2C, breakage such as a crack occurs in a portion exceeding the strength limit. Therefore, when delamination occurs in the fiber reinforced resin layer 20 of the tank shoulder portion 106, particularly in the shoulder inner layer region 24 on the inner layer side, the strength development of the shoulder portion decreases and the high-pressure tank is damaged. It is desirable to replace the high-pressure tank as soon as possible. In the inspection system 1000, the determination unit 120 detects whether or not delamination occurs inside the fiber reinforced resin layer 20 of the high-pressure tank 100 as described below.

  FIG. 3 is an explanatory diagram showing a detection flow of delamination of the fiber reinforced resin layer 20 of the tank shoulder portion 106. The determination unit 120 starts delamination detection processing described below with the start of the fuel cell vehicle, and ends with the stop of the fuel cell vehicle. The determination unit 120 may detect an acceleration greater than a preset value from the detection signal output from the acceleration sensor 130, and may cause delamination in the fiber reinforced resin layer 20 of the high-pressure tank 100 due to road surface interference or the like. Wait until it is detected that an impact has been applied (step S10).

  When an impact is applied, the determination unit 120 operates the peeling state detection sensor 110 to detect the state of delamination of the fiber reinforced resin layer 20 (step S20). Specifically, the determination unit 120 outputs ultrasonic waves for measurement from the transmitter of the peeling state detection sensor 110 toward the fiber reinforced resin layer 20 and measures the ultrasonic waves received by the receiver. An output signal output from the waver is received as a sensor output signal from the peeling state detection sensor 110. In this example, since the peeling state detection sensors 110 are respectively installed on the tank shoulder portions 106 of the dome portions 104 (104e, 104b) on both sides, the above measurement is separately performed by each peeling state detection sensor 110. Is done. And the determination part 120 analyzes the received measurement result and determines whether delamination exists in a shoulder part inner layer area | region (step S30).

FIG. 4 is a graph illustrating an example of a sensor output signal output from the peeling state detection sensor 110. The vertical axis indicates the sensor output, that is, the magnitude of the measured ultrasonic wave. The horizontal axis is the elapsed time t from the time when the ultrasonic wave is output from the transmitter to the surface . The elapsed time t and the wavelength λ of the ultrasonic wave propagating through the fiber reinforced resin layer 20 (= Ct / f, Ct: sound velocity, f: frequency of ultrasonic wave), and the depth from the surface of the fiber reinforced resin layer 20 derived from the above.

  As shown in FIG. 4, when there is delamination, as can be seen by comparing the sensor output signal when there is no delamination (broken line) and the sensor output signal when there is delamination (solid line) In this case, a phase shift occurs as a signal state change. As described above, since the ultrasonic wave output from the transmitter and propagating through the fiber reinforced resin layer 20 is reflected at the interface between the resin layer and the air layer (peeling), it is received by the receiver. This is because the phase of the ultrasonic wave changes depending on the presence or absence of delamination. Therefore, it is possible to determine the presence / absence of delamination by analyzing the presence / absence of phase shift in the sensor output signal. For example, it is possible to detect the occurrence of delamination when a phase shift of a preset allowable value (ε) or more occurs with respect to a signal in the absence of delamination. Then, based on the time from the start of ultrasonic output until the detection of the phase shift, it is possible to determine at which position in the depth from the surface of the fiber reinforced resin layer 20 the delamination position is. It can be determined whether or not it is in the shoulder inner layer region 24.

Here, it is known that the propagation of the ultrasonic wave emitted from the transmitter of the peeling state detection sensor 110 in the circumferential direction around the tank axis CX is much faster than the propagation in the inner layer direction (depth direction). . For this reason, the ultrasonic wave received by the wave receiver of the peeling state detection sensor 110 becomes a composite wave of ultrasonic waves propagated in the inner layer direction at each position in the circumferential direction. Therefore, in this example, it is possible to obtain the position in the depth direction from the surface of the fiber reinforced resin layer 20 as the delamination position, but it occurs at any position in the circumferential direction of the fiber reinforced resin layer 20. I can't ask for it. Moreover, the ultrasonic wave emitted from the transmitter of the peeling state detection sensor 110 propagates not only in the circumferential direction around the tank axis CX but also in all directions. However, the time required for the ultrasonic wave emitted from the transmitter to propagate in the circumferential direction at the tank shoulder 106 provided with the peeling state detection sensor 110 and received by the receiver can be obtained in advance by calculation. . Therefore, by limiting the measurement time by the receiver based on the known circumferential propagation time, it is possible to measure only the propagation in the circumferential direction in the tank shoulder 106.

  The determination unit 120 determines whether there is delamination in the shoulder inner layer region 24 based on the phase shift of the sensor output signal (step S30 in FIG. 3). If delamination exists in the shoulder inner layer region 24, the control unit of the fuel cell vehicle is notified of the occurrence of delamination, and a tank replacement warning is displayed by the control unit of the fuel cell vehicle (step S40). ). The tank replacement warning display can be performed by various methods such as turning on a warning lamp or displaying a tank replacement warning on a display monitor.

  When the delamination does not exist in the shoulder inner layer region 24 (step S30; No), or after issuing a warning for tank replacement (step S40), the determination unit 120 notifies the recording device (not shown) of the interlayer. The detection result of the peeling state is recorded (step S50). As the detection result of the delamination state, data indicating the presence or absence of delamination and data indicating the position of delamination are recorded. Also, sensor output signal data may be recorded. After executing the recording of the detection result (step S50), the determination unit 120 returns to the start position of the delamination detection process (step S10), and each time the occurrence of an impact is detected by the acceleration sensor 130, the determination unit 120 performs step S20 to step S50. Repeatedly.

  As described above, in this embodiment, when an impact due to road surface interference or the like is detected in a fuel cell vehicle, delamination occurs in the shoulder inner layer region of the fiber reinforced resin layer in the tank shoulder of the high-pressure tank. Whether or not to do so is detected. Thereby, it can be predicted in advance that the strength development property of the high-pressure tank is reduced at the shoulder portion of the tank, and as a result, the high-pressure tank may be damaged. Then, early replacement of the high-pressure tank can be promoted.

  FIG. 5 is an explanatory view showing a high-pressure tank inspection system as a modification of the first embodiment. In the inspection system 1000 of FIG. 1, a case where a peeling state detection sensor 110 including a transmitter and a receiver is installed on the outer peripheral side surface of the tank shoulder portion 106 is described as an example. However, as shown in the inspection system 1000B of the modified example (FIG. 5), the transmitter 112 and the receiver 114, which are separately installed along the circumferential direction, are separated from the outer peripheral surface of the tank shoulder 106 by one peeling. It can also be used as a state detection sensor. In this case, it is also possible to use two peeling state detection sensors 110 and use one as the transmitter 112 and the other as the receiver 114. In the case of this modification as well, delamination occurs in the inner layer region of the fiber reinforced resin layer in the tank shoulder of the high-pressure tank when an impact due to road surface interference is detected in the fuel cell vehicle. It can be detected whether or not.

  In the present embodiment, the case where the peeling state detection sensor 110 is installed on the tank shoulders 106 on both the valve side and the end side is shown, but only one of them may be provided. The same applies to the following embodiments.

  In the delamination detection flow of the present embodiment, every time the occurrence of an impact is detected by the acceleration sensor 130, a process for detecting the presence or absence of delamination is performed (FIG. 3). However, the present invention is not limited to this. For example, after an impact is detected by the acceleration sensor 130, for example, when a periodic timing, a gas filling timing, a fluctuation amount of the tank internal pressure becomes a certain amount or more, etc. In addition to the timing at which the occurrence of an impact is detected by the acceleration sensor 130 at various timings, a process for detecting the presence or absence of delamination may be performed. In addition, regardless of the detection of the impact by the acceleration sensor 130, the detection process for the presence / absence of delamination may be repeatedly performed at the various timings described above.

B. Second embodiment:
FIG. 6 is an explanatory diagram showing a high-pressure tank inspection system as a second embodiment. This inspection system 1000 </ b> C shows a configuration in which a plurality of peeled state detection sensors 110 are installed along the circumferential direction on the outer peripheral surface of the tank shoulder 106. Specifically, four peeling state detection sensors 110a to 110d are installed at equal intervals along the circumferential direction. In the case of this configuration, as will be described below, at least any one of the four regions Aab, Abc, Acd, Ada along the circumferential direction between any two of the four peeling state detection sensors 110a to 110d. It can be determined whether delamination occurs in the region.

  For example, when an ultrasonic wave is output from the transmitter of the first peeling state detection sensor 110a, the receivers of the first to fourth peeling state detection sensors 110a to 110d propagate the ultrasonic waves to the respective positions. And output a sensor output signal corresponding to each detected ultrasonic wave. At this time, the amplitude of the phase shift signal in the sensor output signals of the first to fourth peeling state detection sensors 110a to 110d serving as receivers varies depending on the positional relationship in the circumferential direction with respect to the delamination position. Specifically, the amplitude decreases as the distance increases.

  Therefore, for example, when the amplitude of the phase shift signal of the sensor output signal of the second peeling state detection sensor 110b is the largest and the amplitude of the phase shift signal of the sensor output signal of the third peeling state detection sensor 110c is the second largest. To do. In this case, delamination has occurred in the region Abc between the second peeling state detection sensor 110b and the third peeling state detection sensor 110c, and in the region on the second peeling state detection sensor 110b side. It is possible to specify up to. If the number of peeling state detection sensors 110 installed along the circumferential direction is increased, the position along the circumferential direction can be detected more accurately as the delamination position according to the number of sensors installed. is there.

  The amplitude of the sensor output signal of each peeling state detection sensor may vary depending on the positional relationship between the transmitter and the peeling state detection sensor and the positional relationship between the transmitter position and the delamination position. is there. Therefore, for example, the position of the peeling state detection sensor that functions as a transmitter that outputs ultrasonic waves is sequentially switched, and in the case of FIG. 6, the four peeling state detection sensors 110a to 110d are sequentially switched to serve as a transmitter. It is also possible to perform measurement and measure each, and obtain the position of delamination based on the signal with the most significant signal change according to the occurrence of delamination.

  FIG. 7 is an explanatory diagram showing a high-pressure tank inspection system as a modification of the second embodiment. In FIG. 7, the acceleration sensor 130 and the determination unit 120 are omitted. In the inspection system 1000 </ b> C of FIG. 6 described above, a case where a plurality of peeling state detection sensors 110 are circumferentially installed along the circumferential direction on the outer peripheral surface of the tank shoulder portion is described as an example. However, in the inspection system 1000D of the modified example (FIG. 7), a plurality of peeling state detection sensors 110 (110a1 to 110f1, 110a2 to 110f2) are installed in a circumferential shape in a plurality of rows along the direction of the tank axis CX. Is shown. In the case of this configuration, it is possible to obtain not only the position along the circumferential direction but also the position along the tank axis CX as the position of delamination that occurs in the tank shoulder 106.

For example, as described with reference to FIG. 6, the delamination state detection sensor 110 at the same position on the CX axis can determine the delamination on the circumference of the position. For example, on the first circumference C1 (including the periphery of the first circumference C1) by the peeling state detection sensors 110a1 to 110f1 (110d1 to 110f1 are not shown) provided along the first circumference C1. The position of the delamination at the center is obtained, and the second circumference C2 ( first circumference) is detected by the peeling state detection sensors 110a2 to 110f2 (110d2 to 110f2 are not shown) provided along the second circumference C2. The position of the delamination above (including the periphery of C1) can be determined.

  In addition, the ultrasonic wave emitted from the transmitter of any one peeling state detection sensor is received by the receiver of each peeling state detection sensor, and only the position along the circumferential direction from the difference of the received signals. In addition, it is possible to obtain the position along the direction of the tank axis CX. For example, in FIG. 7, when an ultrasonic wave is emitted from the transmitter of the peeling state detection sensor 110a1, an output is made based on the ultrasonic waves received by the receivers of the peeling state detection sensors 110a1 to 110f1 and 110a2 to 110f2. The magnitude of the amplitude of the phase shift signal of the sensor output signal is compared. Thereby, it turns out that there exists delamination between the positions of the four largest peeling state detection sensors. And the position of delamination can be calculated | required by the interpolation based on the position of four peeling state detection sensors, and each signal amplitude.

  In the second embodiment and the modified example, as in the modified example (FIG. 5) of the first embodiment, it is also possible to configure the peeling state detection sensor with separate transmitters and receivers.

C. Third embodiment:
FIG. 8 is an explanatory diagram showing a high-pressure tank inspection system as a third embodiment. In this inspection system 1000E, a plurality of peeling state detection sensors 112 are installed along the circumferential direction on the outer peripheral surface of the tank shoulder 106, and the transmitter is provided on the inner peripheral surface of the tank shoulder 106. 1 shows a configuration in which the receivers 114 of a plurality of peeled state detection sensors are installed so as to face 112. A connection line (for example, metal wiring) between each receiver 114 and the determination unit 120 is tanked via a wiring extraction region (not shown) of a seal structure (for example, hermetic seal) provided in the plug 50. It is taken out from the inside of the tank.

  Also in the case of the present embodiment, the ultrasonic waves output from the respective transmitters 112 are received by the receivers 114 disposed opposite to each other, and the position of the phase shift in the sensor output signal of each receiver 114 and From the amplitude, the position along the circumferential direction and the position in the depth direction can be obtained as the position of delamination.

  Also in this embodiment, similarly to the modification of the second embodiment (FIG. 7), a plurality of transmitters 112 are installed in a plurality of rows in a plurality of rows along the direction of the tank axis CX. And it is good also as a structure which installed the some receiver 114 so that it might respectively oppose the some transmitter 112. FIG. In this way, as in the modification of the second embodiment, not only the position along the circumferential direction but also the position along the direction of the tank axis CX as the position of delamination that occurs in the tank shoulder 106. Can also be sought.

  In the present embodiment, a configuration in which the transmitter 112 is installed on the outer peripheral surface of the tank shoulder 106 and the receiver is installed on the inner peripheral surface of the tank shoulder 106 is described as an example. The transmitter 112 may be installed on the inner peripheral surface of the tank shoulder 106 and the receiver may be installed on the outer peripheral surface of the tank shoulder 106.

D. Fourth embodiment:
FIG. 9 is an explanatory diagram showing an inspection system for a high-pressure tank as a fourth embodiment. This inspection system 1000F shows a configuration in which a plurality of peeled state detection sensors 116 are installed on the inner peripheral surface of the tank shoulder 106 along the circumferential direction. The peeling state detection sensor 116 is a metal strain gauge for measuring the amount of strain in the tank. In addition, the connection line (for example, metal wiring) of each peeling state detection sensor 116 and the determination part 120F is the wiring extraction area | region of the seal structure provided in the plug 50 similarly to the case of 3rd Embodiment (FIG. 8). It is taken out from the inside of the tank via the (not shown).

  FIG. 10 is a graph showing an example of the relationship between the tank internal pressure and the strain amount when there is no delamination. As shown in FIG. 10, the relationship between the tank internal pressure and the strain amount (also referred to as “reference strain amount”) (hereinafter also referred to as “reference strain characteristic”) is obtained in advance in a high-pressure tank where delamination does not occur. The determination unit 120F holds the obtained reference distortion characteristics as data in a storage unit (not shown). When the amount of strain measured by the peeled state detection sensor 116 is in the region above the reference strain characteristic curve (hatched region in FIG. 10), it is larger than the reference strain amount in the tank internal pressure at the time of measurement. Therefore, it is considered that delamination has occurred.

  Therefore, when the impact is detected by the acceleration sensor 130, the determination unit 120F activates the peeled state detection sensor 116 to measure the strain amount in the tank shoulder 106 of the high-pressure tank 100. And based on the measured distortion amount, the presence or absence of delamination is determined as follows. That is, the reference strain amount corresponding to the tank internal pressure at the time of measurement is obtained with reference to data indicating the reference strain characteristics. When the measured strain amount is larger than the reference strain amount, it can be determined that delamination has occurred. And the position of the depth direction of delamination can be calculated | required as follows, for example, and it can be judged whether delamination has generate | occur | produced in the shoulder inner layer area | region 24 based on this.

  FIG. 11 is a graph showing an example of the relationship between the position in the depth direction where delamination occurs and the amount of strain using a plurality of tank internal pressures as parameters. As shown in FIG. 11, the relationship between the position in the depth direction (distance from the tank surface) where the delamination occurs and the amount of strain are determined in advance for each of the plurality of tank internal pressures, and the determination unit 120F. Holds the data in a storage unit (not shown). Referring to the data held in the storage unit, as shown in FIG. 11, the tank internal pressure at the time of strain measurement and the distance Xd from the tank surface corresponding to the measured strain (εd) are obtained. The position in the depth direction where peeling has occurred can be determined. As the measured strain amount (εd), for example, it is preferable to use the maximum value among the strain amounts measured by the plurality of peeled state detection sensors 116.

  Note that the position along the circumferential direction of delamination becomes larger as the magnitude of strain measured by a plurality of peeling state detection sensors 116 installed along the circumferential direction is closer to the position of delamination, This can be obtained by comparing the amount of strain measured by each peeling state detection sensor 116.

  In the case of the present embodiment, the position along the circumferential direction and the position in the depth direction are obtained as the presence / absence of delamination and the position of delamination from the amount of strain measured by each delamination state detection sensor 116. Is possible.

  Also in the present embodiment, a plurality of peeled state detection sensors 116 may be arranged circumferentially in a plurality of rows along the direction of the tank axis CX. In this way, it is possible to obtain not only the position along the circumferential direction but also the position along the direction of the tank axis CX as the position of delamination that occurs in the tank shoulder 106.

  In the present embodiment, the configuration in which the peeling state detection sensor 116 using a metal strain gauge is installed on the inner peripheral surface of the tank shoulder 106 has been described as an example. Alternatively, the peeling state detection sensor 116 may be installed.

  Further, in the present embodiment, a configuration using a metal strain gauge as the peeling state detection sensor 116 has been described as an example, but a fiber Bragg grating (Fiber Bragg Grating) is used as a peeling state detection sensor for measuring strain. , FBG) may be used. However, when an FBG is used, an FBG fiber optic cable connecting the FBG sensor unit, laser light source, detector, sensor unit, laser light source, and detector installed on the tank shoulder 106 is used. And are provided. Based on the amount of strain represented by the signal output from the detector, the determination unit can detect the state of delamination as in the case of the metal strain gauge.

E. Fifth embodiment:
FIG. 12 is an explanatory diagram showing a high-pressure tank inspection system as a fifth embodiment. This inspection system 1000G shows a configuration in which a plurality of peeled state detection sensors 118 are installed along the circumferential direction on the outer peripheral side surface of the tank shoulder portion 106. The peeling state detection sensor 118 is an acoustic emission (AE) sensor. A peeling state detection sensor 118 using an AE sensor can detect a frequency band sound generated in accordance with delamination.

  Therefore, when the impact is detected by the acceleration sensor 130, the determination unit 120G activates the peeling state detection sensor 118 and measures the sound generated in the tank shoulder 106 of the high-pressure tank 100. And when the sound of the frequency band which generate | occur | produces according to delamination is contained in the measured sound, it can determine with delamination having generate | occur | produced. The position in the depth direction of the delamination is output from the AE sensor because, for example, the sound intensity according to the delamination detected by the AE sensor changes according to the distance from the delamination position. It can be determined according to the amplitude of the signal to be determined, and based on this, it can be determined whether or not delamination occurs in the shoulder inner layer region 24. The circumferential position of delamination that occurs in the tank shoulder 106 can be obtained by a derivation method such as a general position location method in the AE sensor.

  In the case of this embodiment, by detecting the sound corresponding to the delamination by the delamination state detection sensor 118, the presence / absence of delamination and the position of delamination as well as the position along the circumferential direction and the depth direction It is possible to determine the position.

  Also in the present embodiment, a plurality of peeled state detection sensors 118 may be arranged circumferentially in a plurality of rows along the direction of the tank axis CX. In this way, not only the position along the circumferential direction but also the position along the direction of the tank axis CX can be obtained based on the position location method or the like as the position of delamination that occurs in the tank shoulder 106. Is possible.

  In the present embodiment, the configuration in which the peeling state detection sensor 118 using the AE sensor is installed on the outer peripheral side surface of the tank shoulder portion 106 has been described as an example. A configuration in which the peeling state detection sensor 118 is installed may be employed.

  The present invention is not limited to the above-described embodiments, examples, and modifications, and can be realized with various configurations without departing from the spirit thereof. For example, the technical features in the embodiments, examples, and modifications corresponding to the technical features in each embodiment described in the summary section of the invention are to solve some or all of the above-described problems, or In order to achieve part or all of the above effects, replacement or combination can be performed as appropriate. Further, if the technical feature is not described as essential in the present specification, it can be deleted as appropriate.

DESCRIPTION OF SYMBOLS 10 ... Liner 11 ... Cylinder part 12 ... Dome part 20 ... Fiber reinforced resin layer 24 ... Shoulder inner layer area 30 ... Valve side base 40 ... End side base 50 ... Plug 100 ... High pressure tank 102 ... Cylinder part 104 ... Dome part 104b ... Dome part 104e ... Dome part 106 ... Tank shoulder part 110 ... Peeling state detection sensor 110a-110d ... Peeling state detection sensor 112 ... Transmitter 114 ... Wave receiver 116 ... Peeling state detection sensor 118 ... Peeling state detection sensor 120 ... Determination Part 120F ... Determining part 120G ... Determining part 1000 ... Inspection system 1000B to 1000G ... Inspection system CX ... Tank axis

Claims (5)

An inspection method for a high-pressure tank for inspecting the state of a high-pressure tank in which a fiber reinforced resin layer is formed on the outer periphery of a tank container,
The high-pressure tank has a cylindrical cylinder part, and dome parts on both sides of the cylinder part,
A signal that changes depending on the state of delamination in the fiber reinforced resin layer on the outer peripheral surface or the inner peripheral surface of the tank shoulder toward the tip of the dome portion from the boundary between the cylinder portion and the dome portion. Install one or more peeling state detection sensors to output,
Based on the signal output from the peeling state detection sensor, it is determined whether the delamination exists in the fiber reinforced resin layer in the tank shoulder,
The peeling state detection sensor is an ultrasonic sensor having a transmitter and a receiver,
A signal output from the peeling state detection sensor is output from the receiver that has received the composite wave of the ultrasonic wave emitted from the transmitter and propagated to each position in the circumferential direction of the tank shoulder. Signal
The determination of whether or not the delamination exists is performed by analyzing the presence or absence of a phase shift in the signal . A method for inspecting a high-pressure tank according to claim 1,
When the delamination exists, based on a signal output from the delamination state detection sensor, the position of the delamination in the depth direction of the fiber reinforced resin layer is obtained, and the inner layer side of the fiber reinforced resin layer is determined. A method for inspecting a high-pressure tank, comprising determining whether or not the delamination exists in a shoulder inner layer region. A method for inspecting a high-pressure tank according to claim 1 or 2,
A plurality of peeling state detection sensors are installed along at least the circumferential direction of the outer peripheral side surface or the inner peripheral side surface of the tank shoulder,
When the delamination exists, the position of the delamination along the circumferential direction of the surface of the tank shoulder is obtained based on a plurality of signals output from the plurality of delamination state detection sensors. Inspection method for high pressure tanks. An inspection system for inspecting the state of a high-pressure tank in which a fiber reinforced resin layer is formed on the outer periphery of a tank container,
The high-pressure tank has a cylindrical cylinder part, and dome parts at both ends of the cylinder part,
Provided on the outer peripheral surface or inner peripheral surface of the tank shoulder from the boundary between the cylinder portion and the dome portion toward the tip of the dome portion, and changes depending on the state of delamination in the fiber reinforced resin layer One or more peeling state detection sensors that output signals;
Based on a signal output from the peeling state detection sensor, a determination unit that determines whether the delamination exists in the fiber reinforced resin layer in the tank shoulder, and
Equipped with a,
The peeling state detection sensor is an ultrasonic sensor having a transmitter and a receiver,
A signal output from the peeling state detection sensor is output from the receiver that has received the composite wave of the ultrasonic wave emitted from the transmitter and propagated to each position in the circumferential direction of the tank shoulder. Signal
The determination unit determines whether the delamination exists by analyzing the presence or absence of a phase shift in the signal.
A high-pressure tank inspection system characterized by A high-pressure tank in which a fiber reinforced resin layer is formed on the outer periphery of the tank container,
The high-pressure tank has a cylindrical cylinder part, and dome parts at both ends of the cylinder part,
A signal that changes depending on the state of delamination in the fiber reinforced resin layer on the outer peripheral surface or the inner peripheral surface of the tank shoulder toward the tip of the dome portion from the boundary between the cylinder portion and the dome portion. One or more peeling state detection sensors for output are provided ,
The peeling state detection sensor is an ultrasonic sensor having a transmitter and a receiver,
A signal output from the peeling state detection sensor is output from the receiver that has received the composite wave of the ultrasonic wave emitted from the transmitter and propagated to each position in the circumferential direction of the tank shoulder. The high-pressure tank is a signal that includes a phase shift when the delamination exists .

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