JP6822398B2 - High-pressure tank member inspection method, high-pressure tank member manufacturing method, high-pressure tank manufacturing method, and high-pressure tank member inspection device - Google Patents

Description

The present invention relates to a method for inspecting a member for a high pressure tank, a method for manufacturing a member for a high pressure tank, a method for manufacturing a high pressure tank, and an inspection device for a member for a high pressure tank. More specifically, the present invention provides a method for inspecting a member for a high pressure tank, a method for manufacturing a member for a high pressure tank, and a high pressure capable of detecting whether the member for a high pressure tank is a good product or a defective product with high accuracy. The present invention relates to a method for manufacturing a tank and an inspection device for members for a high-pressure tank.

In recent years, fuel cell electric vehicles have been attracting attention in order to respond to the depletion of petroleum fuels and the demand for reduction of harmful gas emissions. A fuel cell electric vehicle is equipped with a fuel cell that generates electricity by electrochemically reacting hydrogen with oxygen in the air, and supplies the electricity generated by the fuel cell to a motor as a driving force. When the fuel cell is a hydrogen battery, the automobile is equipped with a tank for high-pressure hydrogen. As an example, the high-pressure hydrogen tank is composed of a resin liner member and a fiber-reinforced resin layer that covers the outside of the liner member. The liner member is made of resin, metal such as aluminum or iron, or the like. Among these, resin liner members are being developed because they are lightweight and can be manufactured at low cost due to their excellent moldability.

However, the tank having the resin liner member is liable to be deformed or broken when the high pressure gas is repeatedly filled and released. Therefore, a high-pressure tank liner containing a resin composition and a high-pressure gas tank containing the liner have been studied in order to suppress such deformation and destruction of the tank (Patent Document 1).

Special Table 2014-501818

However, the high-pressure gas tank manufactured by using the molded product described in Patent Document 1 may be deformed when the high-pressure gas (particularly high-pressure hydrogen gas) is repeatedly filled and released, resulting in a decrease in yield. It was a factor. The cause of such a sudden abnormality was unknown, and there was no inspection method for it.

The present invention has been made in view of such a conventional problem, and it is possible to detect with high accuracy whether the high-pressure tank member is a good product or a defective product, and deformation or the like may occur in the future. It is an object of the present invention to provide a method for inspecting a member for a high pressure tank, a method for manufacturing a member for a high pressure tank, a method for manufacturing a high pressure tank, and an inspection device for a member for a high pressure tank, which can detect a member for a high pressure tank in advance. ..

As a result of diligent studies to solve the above problems, the present inventors have found that factors such as deformation of the tank are caused by impurities and voids existing in the high-pressure tank member. Further, the present inventors have focused on the fact that the presence or absence of the above impurities can be confirmed by radiating X-rays to the member and detecting the transmitted X-rays in the stage before molding the tank. The invention was completed.

That is, in the method for inspecting a high-pressure tank member according to one aspect of the present invention that solves the above problems, an X-ray radiating device emits X-rays to the high-pressure tank member, and X-rays transmitted through the high-pressure tank member are emitted. , A method of inspecting a member for a high-pressure tank for defect inspection using an X-ray detector, wherein one wall surface of the member for the high-pressure tank is arranged between the X-ray radiating device and the X-ray detector. This is an inspection method for high-pressure tank members, which is inspected in a state.

Further, the method for manufacturing the high-pressure tank member according to one aspect of the present invention includes an inspection step for carrying out the inspection method for the high-pressure tank member, a high-pressure tank member determined to be defective in the inspection step, and a non-defective product. A method for manufacturing a high-pressure tank member, which includes a sorting step for distinguishing the determined high-pressure tank member.

Further, the method for manufacturing a high-pressure tank according to one aspect of the present invention includes an inspection step for carrying out the inspection method for the liner member for a high-pressure tank, a liner member determined to be defective in the inspection step, and a non-defective product. This is a method for manufacturing a high-pressure tank, which includes a sorting step for distinguishing a liner member and an outer layer forming step for forming an outer layer for reinforcement with respect to a liner member determined to be a non-defective product.

In addition, the inspection device for the high-pressure tank member according to one aspect of the present invention is an inspection device for carrying out the above-mentioned inspection method for the high-pressure tank member, and includes an X-ray radiating device and an X-ray detector. The X-ray radiating device emits X-rays to the high-pressure tank member, and the X-ray detector is an inspection device for the high-pressure tank member that detects X-rays transmitted through the high-pressure tank member.

FIG. 1 is a schematic diagram for explaining an inspection method according to an embodiment of the present invention. FIG. 2 is a schematic diagram for explaining a conventional inspection method. FIG. 3 is a schematic diagram for explaining a drive type of an X-ray radiating device or the like in the inspection method according to the embodiment of the present invention. FIG. 4 is a schematic diagram for explaining an inspection method according to an embodiment of the present invention.

<Inspection method for high-pressure tank members>
An inspection method for a member for a high-pressure tank according to an embodiment of the present invention (hereinafter, also simply referred to as an inspection method) will be described. The inspection method of the present embodiment is a method of inspecting a member for a high pressure tank. The inspection method is to radiate X-rays from the X-ray radiating device to the high-pressure tank member, and detect the X-rays that have passed through the high-pressure tank member using an X-ray detector, so that the high-pressure tank member is a good product. It is a method of inspecting whether the product is defective or defective. For the sake of clarification, the configuration of the high-pressure tank will be described in detail before the description of the inspection method of the present embodiment.

(High pressure tank)
A high-pressure tank is a container for filling a high-pressure gas such as compressed gas or liquefied gas. For example, when the high-pressure gas is hydrogen, a container for mounting a fuel cell vehicle, a container for transporting high-pressure hydrogen, and a hydrogen station accumulator. and so on. The structure of the high-pressure tank is not particularly limited. As an example, the high pressure tank includes a liner member, one or more reinforcing layers covering the liner member, and a supply system (valve member, various piping systems, etc.) for supplying high pressure gas to the fuel cell.

The shape of the high pressure tank is not particularly limited. As an example, the high pressure tank has a substantially cylindrical shape. The high-pressure tank is formed with an opening for filling the tank with the high-pressure gas or for taking out the high-pressure gas from the tank. The opening is closed by the supply system. In the present embodiment, the high-pressure tank member is a member constituting the high-pressure tank, and examples thereof include a liner member and a member after forming a reinforcing layer on the liner member.

-Liner member The liner member is a tank container that constitutes the housing of the high-pressure tank. The shape of the liner member is not particularly limited. As an example, the liner member has a substantially cylindrical shape, and a storage space is formed inside (an example of "a member for a high-pressure tank in which a predetermined space is formed inside"). The accommodation space is filled with high pressure gas. The liner member is formed with the above-mentioned opening. The liner member may be composed of one member or may be composed of a plurality of divided members. In this case, the members divided into a plurality of parts can be integrated by joining or the like. Examples of the method for producing the liner member include blow molding and injection molding. In particular, when a liner member is manufactured by injection molding, impurities are likely to be mixed in and voids are likely to be formed. On the other hand, the inspection method of the present embodiment is suitable because impurities and voids can be appropriately detected even when the liner member is manufactured by injection molding in this way.

The material of the liner member is not particularly limited. As an example, the liner member is made of resin, metal such as aluminum or iron, or the like. Among these, the resin liner member is relatively liable to form voids and impurities, and is liable to be deformed or broken after being molded into a high-pressure tank. However, the inspection method of the present embodiment can appropriately detect voids and impurities as described later. Therefore, the inspection method of the present embodiment is particularly suitable when the liner member is made of resin. The resin has a higher X-ray absorption rate, and at least one of the polyolefin resin, the ethylene-vinyl alcohol copolymer, and the polyamide resin is used because impurities and the like in the liner member can be detected more accurately by the X-ray detector described later. It is preferable to include one kind.

Further, the resin more preferably contains a polyamide resin. The polyamide resin has excellent characteristics as a liner member. Further, since the liner member containing the polyamide resin has a high X-ray absorption rate, voids and resin impurities in the polyamide resin can be easily detected. More specifically, for example, when the polyamide resin contains polyolefin having an impurity of 50 μm or more, the liner member made of such a polyamide resin is liable to be deformed or broken in the tank. In particular, when the high-pressure gas is hydrogen gas, the hydrogen gas has a low molecular weight and therefore easily dissolves in the liner member. As a result, even if the liner member has a small amount of voids or impurities, the high-pressure tank for hydrogen gas is likely to be deformed or broken. According to the inspection method of the present embodiment described later, such impurities of 50 μm or more can be easily detected. Therefore, in the inspection method of the present embodiment, when the liner member is made of a polyamide resin, impurities and the like can be detected with high accuracy and can be appropriately discriminated.

Further, the polyamide resin constituting the liner member has the polyamide 6 resin (A) and the melting point measured by DSC measured by the melting point of the polyamide 6 resin (A) + 20 ° C. or lower, and the temperature lowering crystallization temperature measured by DSC measured by the polyamide 6 A polyamide resin composition comprising a polyamide resin (B) having a temperature higher than the temperature-decreasing crystallization temperature of the resin (A), and the polyamide resin (B) is added to 100 parts by weight of the polyamide 6 resin (A). It is preferable to use a polyamide resin composition containing 0.01 to 5 parts by weight. Such a polyamide (A) has an excellent balance of moldability, gas barrier property, rigidity and toughness. Then, by blending a specific amount of the polyamide resin (B) with the polyamide 6 resin (A), the crystallization rate is increased and dense and uniform crystals are formed. As a result, the permeation of hydrogen gas and the dissolution of hydrogen in the resin are suppressed, and the obtained liner member is less likely to have defects even if the high pressure gas (particularly high pressure hydrogen gas) is repeatedly filled and released.

In this embodiment, the polyamide 6 resin (A) is a polyamide resin mainly composed of 6-aminocaproic acid and / or ε-caprolactam. The polyamide 6 resin (A) may be a copolymer of other monomers as long as the object of the present embodiment is not impaired. Here, "as the main raw material" means that the total of 100 mol% or more of the units derived from 6-aminocaproic acid or the unit derived from ε-caprolactam is contained in the total of 100 mol% of the monomer units constituting the polyamide resin. Means. The polyamide 6 resin (A) more preferably contains 70 mol% or more of units derived from 6-aminocaproic acid or ε-caprolactam, and more preferably 90 mol% or more.

In the present embodiment, the polyamide resin (B) has a melting point measured by DSC of + 20 ° C. or lower of the polyamide 6 resin (A), and the temperature-decreasing crystallization temperature measured by DSC is the temperature-decreasing crystallization of the polyamide 6 resin (A). A polyamide resin having a temperature higher than the temperature is preferable. When the melting point of the polyamide resin (B) exceeds the melting point of the polyamide 6 resin (A) + 20 ° C., the dispersibility of the polyamide resin (B) in the polyamide resin composition of the present embodiment tends to decrease. As a result, the effect of improving the crystallization rate tends to be small, and defects are likely to occur due to repeated filling and releasing of high-pressure gas (particularly high-pressure hydrogen gas).

When the temperature lowering crystallization temperature of the polyamide resin (B) is equal to or lower than the temperature lowering crystallization temperature of the polyamide 6 resin (A), the polyamide 6 resin (A) is crystallized in the cooling process from the molten state of the polyamide resin composition. The crystallization rate is faster than the crystallization rate of the polyamide resin (B). In this case, it is difficult to form dense and uniform crystals, and the liner member is liable to have defective points when the high pressure gas is repeatedly filled and released.

The polyamide resin (B) preferably used in this embodiment is polyhexamethylene sebacamide (polyamide 610), polyhexamethylene adipamide (polyamide 66), polypentamethylene adipamide (polyamide 56), or the like. One or more selected from polytetramethylene adipamide (polyamide 46) and polytetramethylene sebacamide (polyamide 410), and polycaproamide (polyamide 6), polyundecaneamide (polyamide 11), polydodecaneamide (polyamide 11). 12), polyhexamethylene sebacamide (polyamide 610), polypentamethylene sebacamide (polyamide 510) and copolymers with one or more selected from polyhexamethylene dodecamide (polyamide 612) are exemplified. Among these, the polyamide resin (B) is more preferably a polyamide 610 resin.

The blending amount of the polyamide resin (B) in the polyamide resin composition of the present embodiment is preferably 0.01 to 5 parts by mass with respect to 100 parts by mass of the polyamide 6 resin (A). When the blending amount of the polyamide resin (B) is less than 0.01 parts by mass, the effect of improving the crystallization rate is not sufficient, and defects occur in the liner member due to repeated filling and release of high-pressure gas. It will be easier to do. On the other hand, when the blending amount of the polyamide resin (B) exceeds 5 parts by mass, the phase separation between the polyamide 6 resin (A) and the polyamide resin (B) in the cooling process from the molten state of the resin composition tends to proceed. Therefore, the effect of improving the crystallization rate is not sufficient, and the liner member is liable to have defective points due to repeated filling and releasing of high pressure gas.

The impact-resistant material (C) may be further blended in the polyamide resin composition. By blending the impact resistant material (C), the resulting liner member can be improved in impact resistance. Further, in a molded product used for applications in which it comes into contact with high-pressure hydrogen, a temperature change (heat cycle) from −40 ° C. or lower to 90 ° C. or higher repeatedly occurs when the high-pressure hydrogen is filled and released. Therefore, for example, when the molded product is a composite product having a resin portion and a metal portion, cracks are likely to occur at the joint portion between the resin portion and the metal portion. On the other hand, by blending the impact resistant material (C), cracking at the joint between the resin portion and the metal portion caused by the repetition of such a heat cycle is suppressed, and the heat cycle resistance of the liner member is improved. obtain.

As the impact resistant material (C), an olefin resin is suitable. The olefin resin is a thermoplastic resin obtained by polymerizing an olefin monomer such as ethylene, propylene, butene, isoprene, and pentene. Among the olefin-based resins, ethylene / α-olefin copolymers and ethylene / α, β-unsaturated carboxylic acid ester copolymers are more preferable, and ethylene / α-olefin copolymers are even more preferable. Further, the olefin resin may be modified with an unsaturated carboxylic acid and / or a derivative thereof. By modifying the olefin resin with an unsaturated carboxylic acid and / or a derivative thereof, the compatibility with the polyamide 6 resin (A) and the polyamide resin (B) is further improved, and the obtained liner member is deformed or deformed. Polyolefins of 50 μm or more, which cause destruction, are unlikely to be contained. The olefin resin is more preferably an unsaturated dicarboxylic acid and an acid anhydride thereof, and further preferably maleic acid or maleic anhydride. The copolymer of ethylene modified with an unsaturated carboxylic acid and / or a derivative thereof and an α-olefin having 3 to 12 carbon atoms further improves the compatibility with the polyamide 6 resin (A) and the polyamide resin (B). It is difficult to be contained as a polyolefin having a size of 50 μm or more, which causes deformation or breakage.

The blending amount of the impact-resistant material (C) in the polyamide resin composition is preferably 1 to 50 parts by mass with respect to 100 parts by mass of the polyamide 6 resin (A). By blending the impact resistant material (C) so as to be 1 part by mass or more, the obtained liner member has further improved heat cycle resistance. Further, the crystallization rate is further improved by blending the impact resistant material (C) so as to be 50 parts by mass or less.

-Reinforcing layer The outer surface of the liner member is covered with one or more reinforcing layers in order to reinforce the liner member. The material of the reinforcing layer is not particularly limited. As an example, the reinforcing layer is a fiber reinforced resin layer. Examples of the fiber-reinforced resin constituting the fiber-reinforced resin layer include carbon fiber-reinforced plastic (CFRP) and glass fiber-reinforced plastic. These fiber reinforced resins may be used in combination. Further, the reinforcing layer made of each fiber reinforced resin may double cover the liner member. When the fiber reinforced resin is, for example, carbon fiber reinforced plastic, the fiber reinforced resin layer includes reinforcing fibers such as carbon fiber reinforced plastic wound around the outer surface of the liner member and a thermosetting resin that binds the reinforcing fibers to each other. Mainly composed of.

Returning to the description of the entire inspection method, it is preferable that the inspection method of the present embodiment is carried out on the liner member of the high-pressure tank before the reinforcing layer is provided. Specifically, the inspection method is to radiate X-rays from the X-ray radiating device to the liner member and detect the X-rays that have passed through the liner member using an X-ray detector, so that the liner member is a non-defective product. Inspect whether it is a defective product or not. The inspection method may be carried out on a liner member formed into a cylindrical shape, or may be carried out on a liner member before being formed into a cylindrical shape.

FIG. 1 is a schematic diagram for explaining the inspection method of the present embodiment. In FIG. 1, it is divided into a substantially bowl shape (a shape composed of a substantially cylindrical cylinder portion 11 and a substantially hemispherical dome portion 12 provided at one end of the cylinder portion 11) before being formed into a cylindrical shape. The liner member 1 is exemplified. In the embodiment shown in FIG. 1, the inspection method emits X-rays to the liner member 1 from the X-ray emitting device 2 arranged inside the liner member 1. The X-rays that have passed through the liner member 1 are detected by the X-ray detector 3 arranged outside the liner member 1. The X-ray radiation range 4 emitted from the X-ray radiation device 2 is not particularly limited. The radiation range 4 may be a range in which at least a part of the emitted X-rays can be detected by the X-ray detector 3.

(X-ray radiating device 2)
The X-ray radiating device 2 is a device for radiating X-rays to the liner member 1. The X-ray radiating device 2 may be a general-purpose X-ray radiating device 2. The shape and dimensions of the X-ray radiating device 2 are not particularly limited. The shape and dimensions of the X-ray radiating device 2 are appropriately determined depending on the place where they are arranged and the like. As an example, when the X-ray radiating device 2 is arranged inside the liner member 1 as shown in FIG. 1, it is a small box body so as not to interfere with the accommodation space of the liner member 1. Further, the X-ray radiating device 2 may be accompanied by a power cable or the like (not shown) for driving the X-ray radiating device 2. In this case, it is preferable that the power cable and the like also have a shape and dimensions that do not interfere with the liner member 1.

(X-ray detector 3)
The X-ray detector 3 is a device for detecting X-rays transmitted through the liner member 1. The X-ray detector 3 may be a general-purpose X-ray detector. As an example, the X-ray detector 3 may be a direct conversion type X-ray detector or an indirect conversion type X-ray detector. More specifically, the X-ray detector 3 is an X-ray film, an image intensifier, a compute radiography (CR), a flat panel detector (FPD), or the like.

Among these, the X-ray detector 3 is an indirect conversion type FPD because it does not require a developing process or the like as compared with the case where an X-ray film is used, and the time required for inspection can be shortened. preferable. Further, the indirect conversion type FPD has no restrictions such as the usable temperature as compared with the direct conversion type detector. Therefore, the indirect conversion type X-ray detector is excellent in handleability.

Further, the indirect conversion type FPD preferably includes a cell type scintillator. In an indirect conversion type FPD, a scintillator panel is used to convert radiation into visible light. The scintillator panel contains an X-ray phosphor such as cesium iodide (CsI), and the X-ray phosphor emits visible light in response to the emitted X-ray, and the emission is emitted by a TFT (thin film transistor) or CCD. X-ray information is converted into digital image information by converting it into an electric signal by (charge-coupled fluorescence). However, in the indirect conversion type FPD, when the X-ray phosphor emits light, visible light is scattered by the phosphor itself, and the sharpness of the image tends to be low. On the other hand, in an FPD in which a cell scintillator is adopted, a phosphor is filled in a cell partitioned by a partition wall, and the influence of light scattering can be suppressed. As a result, the FPD provided with the cell scintillator has high sharpness and can detect impurities and voids in the liner member 1 with high sensitivity.

The cell scintillator used in the inspection method of the present embodiment uses a photosensitive paste containing glass powder and contains glass as a main component because a large area and sharp cell scintillator can be easily formed. It is more preferable that the cell type scintillator is produced by processing the partition wall to be processed by photolithography.

The pixel size of the sensor of the X-ray detector 3 is not particularly limited. As an example, the pixel size of the sensor is preferably 20 to 300 μm. When the pixel size is less than 20 μm, there is a tendency to detect even minute impurities that do not contribute to deformation or destruction of the liner member 1 and erroneously determine a non-defective product as a defective product. Further, with such a pixel size, the image data tends to be enormous, and the time required for signal reading and image processing tends to be long. On the other hand, if the pixel size exceeds 300 μm, impurities and the like may not be sufficiently detected.

FIG. 4 is a schematic diagram for explaining the inspection method of the present embodiment. In FIG. 4, the liner member 1 after being formed into a cylindrical shape is illustrated. In FIG. 4, the liner member 1 is formed with openings 5 for taking out high-pressure gas from the inside of the tank at both ends of the cylindrical shape in the long axis direction. The size of the opening 5 of the liner member 1 is determined in consideration of the gas extraction efficiency, the strength of the joint portion of the supply system, and the like. In the present embodiment, the minimum opening length of the opening 5 (the minimum length of the distance between two points when any two points are selected in the cross section of the opening 5 of the liner member 1. For example, the opening 5 When the shape of is a perfect circle, it is the diameter of a circle, and when it is an ellipse, it is the minor axis of an ellipse) is preferably 5 cm or less. If the minimum opening length of the opening 5 exceeds 5 cm, the strength of the joint of the supply system may decrease. When the liner member has a plurality of openings, the minimum opening length is the shortest of the minimum opening lengths of the plurality of openings.

In the inspection method of the present embodiment, the X-ray radiating device is preferably inserted from the opening 5 of the liner member 1 in which the minimum opening length of the opening 5 is 5 cm or less. According to such a configuration, even in a liner member or the like formed into a cylindrical shape, only one wall surface of the high-pressure tank member can be inspected. Therefore, according to the present embodiment, it is easy to clearly grasp the presence or absence of impurities even in a liner member or the like formed into a cylindrical shape.

The shape of the X-ray emitting device that can be inserted through the opening 5 of the liner member 1 having the minimum opening length of the opening 5 of 5 cm or less is not particularly limited. As an example, the X-ray emitting device has an X-ray source having a rod-shaped shape and having an X-ray generating portion inside the rod-shaped portion. Examples of the shape of the rod-shaped X-ray source include a columnar shape and a prismatic shape. Further, as a rod-shaped X-ray source that can be inserted through the opening 5 of the liner member 1 having a length of 5 cm or less, a columnar X-ray source having a cross-sectional diameter of less than 5 cm or a cross section with respect to the cross section of the rod-shaped portion in the long axis direction is used. Examples thereof include a prismatic source having a diagonal length of less than 5 cm.

The length of the rod-shaped portion is preferably 30 cm or more. If the length of the rod-shaped portion is less than 30 cm, the length of the rod-shaped portion is shorter than that of the liner member 1 molded into a cylindrical shape, and it may not be possible to inspect an arbitrary portion of the liner member 1.

The distance between the X-ray generating portion of the rod-shaped X-ray source and at least one end of the rod-shaped portion is preferably 30 cm or more. When the distance is less than 30 cm, it is difficult for the X-ray generating portion to be sufficiently inserted into the liner member 1 molded into a cylindrical shape, and it may not be possible to inspect any part of the liner member 1.

The liner member 1 preferably has a plurality of openings 5, in which case the rod-shaped X-ray radiating device may penetrate two of the plurality of openings 5 of the liner member 1. preferable. With such a configuration, the rod-shaped X-ray radiating device can be held at two places outside the liner member 1. As a result, the position of the X-ray generator can be easily and precisely controlled.

In the present embodiment, the molding method of the liner member 1 molded into a cylindrical shape is not particularly limited. The liner member is preferably a liner member molded by a method of joining two liner members divided into a substantially bowl shape. Impurities and voids are likely to be formed in the joint portion of the liner member molded in this way, and this is a suitable inspection target according to the present embodiment. In the inspection of the joint, the focal point of the X-ray tube of the X-ray radiating device is preferably arranged on a plane including a substantially circular joint. With such an arrangement, the X-ray radiating device can irradiate the joint portion with X-rays in a direction parallel to the joint surface, as compared with the case where the joint surface is obliquely irradiated with X-rays. , The detection accuracy of impurities and voids is improved.

<About the arrangement of X-ray radiating device 2 etc.>
Next, the arrangement of the X-ray emitting device 2 and the like for more preferably carrying out the inspection method of the present embodiment will be described.

As shown in FIG. 1, the inspection method of the present embodiment is carried out by arranging only the wall surface of 1 of the liner member 1 between the X-ray emitting device 2 and the X-ray detector 3. Further, FIG. 2 is a schematic diagram for explaining a conventional inspection method. As shown in FIG. 2, the conventional inspection method is carried out by arranging the X-ray radiating device 2 and the X-ray detector 3 on the outside so as to sandwich the liner member 1. In this case, a plurality of wall surfaces of the liner member 1 are arranged between the X-ray emitting device 2 and the X-ray detector 3.

The shape of the liner member 1 is not particularly limited. As described above, the liner member 1 has a substantially cylindrical shape in which a predetermined opening is formed. Further, the liner member 1 may be a bowl-shaped member (see FIG. 1) divided into a plurality of parts.

When the inspection method is carried out in the arrangement shown in FIG. 1, only the wall surface of 1 of the liner member 1 is inspected. Therefore, it is easy to clearly grasp the presence or absence of impurities.

Further, in the inspection method of the present embodiment, according to the arrangement shown in FIG. 1, the X-ray emitting device 2 can be arranged inside the liner member 1, and the X-ray detector 3 can be arranged outside the liner member 1. .. In this case, the X-ray radiating device 2 radiates X-rays from the inside to the outside of the liner member 1. Further, the X-ray detector 3 is arranged outside the liner member 1. Therefore, the X-ray detector 3 may be larger than the liner member 1. As a result, even when X-rays are emitted from the X-ray emitting device 2 over a wide area, the X-ray detector 3 can appropriately detect the emitted X-rays. Therefore, the area of the wall surface of the liner member 1 that can be inspected by one X-ray imaging can be increased, and the inspection time can be shortened. Further, since the X-ray detector 3 is arranged outside the liner member 1, the separation distance between the X-ray detector 3 and the wall surface of the liner member 1 may be changed. Therefore, in the inspection method of the present embodiment in which the arrangement illustrated in FIG. 1 is adopted, it is easy to adjust the magnification and the like at the time of X-ray photography according to, for example, the size of impurities and the like. As a result, according to the inspection method of the present embodiment, impurities and the like can be detected more accurately.

The inspection method of the present embodiment may be carried out by arranging the X-ray radiating device 2 outside the liner member 1 and arranging the X-ray detector 3 inside instead of the arrangement shown in FIG. Good. According to such a configuration, the X-ray radiating device 2 is arranged outside the member for the high pressure tank. Therefore, the X-ray radiating device 2 may be larger than the member for the high-pressure tank. As a result, the X-ray emitting device 2 can be enlarged so that it can irradiate a high dose of X-rays. As a result, the X-ray radiating device 2 can acquire an image with a short-time X-ray irradiation, and can shorten the X-ray inspection time. Further, since the X-ray radiating device 2 is arranged outside the high-pressure tank member, the separation distance between the X-ray radiating device 2 and the wall surface of the high-pressure tank member can be changed. Therefore, in this embodiment, for example, the magnification at the time of X-ray photography can be adjusted according to the size of impurities and the like. As a result, according to the present embodiment, impurities and the like can be detected more accurately. The X-ray detector 3 can be arranged inside the high-pressure tank member by inserting it through the opening of the high-pressure tank member.

On the other hand, when the inspection method is carried out in the arrangement shown in FIG. 2, the X-rays emitted from the X-ray radiating device 2 pass through the wall surface of the high-pressure tank member 1. In the X-ray inspection, the thicker the inspection object, the lower the accuracy of detecting impurities. Therefore, the structure that transmits through the wall surface of 2 substantially doubles the thickness of the inspection object as compared with the structure that transmits through the wall surface of 1, so that the accuracy of detecting impurities is lowered. Further, in this case, even when the presence of impurities or the like is detected by the transmitted X-rays, it is not clear which wall surface the impurities or the like are present on, and the impurities may not be clearly grasped.

<About the drive type of X-ray radiation device 2 etc.>
Next, a drive type of the X-ray radiating device 2 or the like for more preferably carrying out the inspection method of the present embodiment will be described with reference to FIGS. 1 and 3. FIG. 3 is a schematic diagram for explaining a drive type of the X-ray radiating device 2 and the like in the inspection method of the present embodiment. In the inspection method of the present embodiment, at least one member of the X-ray detector, the X-ray detector 3, and the liner member 1 may be driven so as to change its position relative to the other member.

Specifically, when the arrangement shown in FIG. 1 is adopted, the inspection method of the present embodiment is to drive the liner member 1 and change the relative position between the X-ray emitting device 2 and the liner member 1. The liner member 1 may be inspected by According to such a drive type, in the inspection method of the present embodiment, the liner member 1 is driven while the positional relationship between the X-ray radiating device 2 and the X-ray detector 3 is maintained. Therefore, X-ray photography can be continuously performed on the liner member 1. As a result, the time required for the inspection can be shortened. In the present embodiment, "continuous X-ray photography is performed" includes a case where a moving image of X-rays is photographed and a case where a plurality of still images are repeatedly photographed while changing the photographing position. ..

The drive type of the liner member 1 is not particularly limited. As shown in FIG. 1, the liner member 1 may be rotationally driven in the predetermined direction indicated by the arrow A1, and may be driven in a direction orthogonal to the X-rays emitted from the X-ray emitting device 2. It may be driven in the same direction or in a predetermined oblique direction.

Further, when the arrangement shown in FIG. 3 is adopted, the inspection method is that the X-ray emitting device 2 is arranged inside the cylindrical liner member 1a and the X-ray detector 3 is arranged outside the liner member 1a. Has been done. In this case, for example, the liner member 1a is rotationally driven in the direction of the arrow A3, and the X-ray radiating device 2 and the X-ray detector 3 are fixedly arranged at predetermined positions, so that the wall surface of the liner member 1a is continuously inspected. Can be done.

Further, when the arrangement is adopted as shown in FIG. 3, the inspection method of the present embodiment is to drive the X-ray radiating device 2 and change the relative position between the X-ray radiating device 2 and the liner member 1a. The liner member 1a may be continuously inspected. More specifically, for example, the liner member 1a is fixedly arranged at a predetermined position, the X-ray emitting device 2 is rotationally driven in the direction of the arrow A4, and the X-ray detector 3 is interlocked with the driving of the X-ray emitting device 2. May be continuously inspected on the wall surface of the liner member 1a by being rotationally driven in the direction of the arrow A5. According to such a configuration, the position where the X-ray is emitted with respect to the liner member 1a can be precisely controlled by driving the X-ray emitting device 2. Therefore, for example, even when the liner member 1a includes a curved portion, X-rays can be sufficiently emitted to such a curved portion. As a result, according to the inspection method of the present embodiment, impurities and the like can be detected more accurately.

According to the inspection method of the present embodiment using the above X-ray emitting device and X-ray detector, impurities and voids existing in the liner member can be detected by detecting the transmitted X-rays. Therefore, the liner member in which these impurities and the like are detected may be appropriately selected as defective products and eliminated. By the way, for example, when a reinforcing layer made of a fiber reinforced resin is formed on a liner member, such a fiber reinforced resin is expensive. However, according to the inspection method of the present embodiment, the liner member is inspected in the stage before molding the high pressure tank. Therefore, the liner member can be determined as a defective product before, for example, a reinforcing layer made of a fiber reinforced resin is formed on the liner member. As a result, the fiber reinforced resin is not wasted. In addition, the yield of the manufactured high-pressure tank is improved.

In particular, the inspection method of the present embodiment is useful when the high pressure gas is hydrogen gas. That is, hydrogen gas has a smaller molecular weight than other gases. Therefore, hydrogen gas easily dissolves in the liner member, and even a small amount of impurities or voids easily causes deformation or destruction of the high-pressure tank. According to the inspection method of the present embodiment, such a small amount of impurities and voids can be detected with high accuracy. Therefore, even when hydrogen gas is filled, the obtained high-pressure tank is less likely to be deformed or destroyed.

<Manufacturing method of high-pressure tank members>
A method for manufacturing a member for a high-pressure tank according to an embodiment of the present invention will be described. The method for manufacturing the high-pressure tank member of the present embodiment includes an inspection process for carrying out the above-mentioned inspection method for the high-pressure tank member, a high-pressure tank member determined to be defective in the inspection process, and a high-pressure determination to be a non-defective product. Includes a sorting step that distinguishes it from tank members. The details will be described below. The method for manufacturing the high-pressure tank member of the present embodiment may include these inspection steps and sorting steps, and other steps are not particularly limited. Therefore, the other steps shown below are examples, and the design can be changed as appropriate.

(Manufacturing process of high-pressure tank member)
This step is a step of manufacturing a member for a high pressure tank. For example, when the high-pressure tank member is a liner member, it can be manufactured by blow molding, injection molding, or the like as described above in the embodiment of the inspection method.

(Inspection process)
This step is a step of inspecting the high-pressure tank member for the presence of voids, impurities, etc. by radiating X-rays to the obtained high-pressure tank member. In the inspection step, the X-ray radiating device and the X-ray detector described above are used in the embodiment of the inspection method. High-pressure tank members in which impurities or the like are detected in the inspection step are determined to be defective, and are sorted and removed in the subsequent sorting step. In this step, the detection result by the X-ray detector is displayed, for example, on an image display device or the like attached to the X-ray detector, or is printed by an image forming device or the like that prints the detection result. .. In addition, the evaluation of non-defective products and defective products based on these detection results may be artificially performed by the evaluator, and a computer that executes a computer program programmed to meet a predetermined criterion (“inspection”). It may be performed mechanically by an example of a "judgment unit for determining whether a product is good or defective based on the result").

Whether the high-pressure tank member is a good product or a defective product is a discontinuous image based on a sudden change in the X-ray absorption rate at the location where impurities etc. are present in the image detected by the X-ray detector. It is judged by whether or not there is a shade of.

(Sorting process)
This step is a step of distinguishing between a high-pressure tank member determined to be a defective product and a high-pressure tank member determined to be a non-defective product in the inspection process. This step may be artificially performed by a sorter, and is an example of a computer that executes a computer program that extracts only defective products (“determination unit for determining whether a defective product or a defective product is based on an inspection result””. ) May be done mechanically. Good high-pressure tank members that have not been sorted in the sorting step can be used as materials for the high-pressure tank.

As described above, according to the method for manufacturing the high-pressure tank member of the present embodiment, impurities and voids existing in the high-pressure tank member can be appropriately detected in the inspection step. Further, the high-pressure tank member in which impurities and the like are detected can be sorted and eliminated in the sorting step. Therefore, only non-defective products can be selected for the high-pressure tank member. The selected high-pressure tank member can be manufactured in a high-pressure tank through subsequent steps. As a result, according to the method for manufacturing the liner member of the present embodiment, the subsequent steps may be omitted for the defective high-pressure tank member. In addition, the yield of the manufactured high-pressure tank is improved.

<Manufacturing method of high pressure tank>
A method for manufacturing a high-pressure tank according to an embodiment of the present invention will be described. The high-pressure tank manufacturing method of the present embodiment includes an inspection process for carrying out the above-mentioned inspection method for the high-pressure tank liner member, a liner member determined to be defective in the inspection process, and a liner member determined to be non-defective. It includes a sorting step for distinguishing and an outer layer forming step for forming an outer layer for reinforcement with respect to the liner member determined to be a non-defective product. The details will be described below. The method for manufacturing the high-pressure tank of the present embodiment may include these inspection steps, sorting steps, and outer layer forming steps, and other steps are not particularly limited. Therefore, the other steps shown below are examples, and the design can be changed as appropriate.

(Making process of liner member)
This step is a step of manufacturing a liner member. The liner member can be manufactured by blow molding, injection molding or the like as described above in the embodiment of the inspection method.

(Inspection process)
This step is a step of inspecting the liner member for the presence of voids, impurities, etc. by radiating X-rays to the obtained liner member. In the inspection step, the X-ray radiating device and the X-ray detector described above are used in the embodiment of the inspection method. Further, the inspection step is the same as the above-mentioned inspection step in the embodiment of the method for manufacturing the liner member for a high pressure tank. In the inspection process, impurities and voids existing in the liner member are appropriately detected.

(Sorting process)
This step is a step of distinguishing between a liner member determined to be a defective product and a liner member determined to be a non-defective product in the inspection process. The sorting step is the same as the sorting step described above in the embodiment of the method for manufacturing the liner member for a high pressure tank. In the sorting step, the defective liner member is appropriately sorted, and the subsequent outer layer forming step is carried out only for the non-defective liner member.

(Outer layer forming process)
This step is a step of forming an outer layer (reinforcing layer) for reinforcement on the liner member determined to be a non-defective product. As described above in the embodiment of the inspection method, the reinforcing layer is preferably a fiber reinforced resin layer, and one or more reinforcing layers are provided on the outer surface of the liner member. The liner member provided with the reinforcing layer is further attached with a supply system (valve member, various piping systems, etc.) for supplying high-pressure gas to the fuel cell, and is used as a high-pressure tank.

As described above, according to the method for manufacturing a high-pressure tank of the present embodiment, impurities and voids existing in the liner member can be appropriately detected in the inspection step. Further, the liner member in which impurities or the like are detected can be sorted and eliminated in the sorting step. Further, the reinforcing layer is formed only on the liner member determined to be a non-defective product. Therefore, according to the method for manufacturing the high-pressure tank of the present embodiment, the reinforcing layer is not formed on the liner member which is a defective product, so that, for example, the fiber reinforced resin is not wasted. In addition, the yield of the manufactured high-pressure tank is improved.

<Inspection device for high-pressure tank members>
An inspection device for a member for a high-pressure tank according to an embodiment of the present invention will be described. The inspection device for the high-pressure tank member of the present embodiment is an apparatus for carrying out the above-mentioned inspection method for the high-pressure tank member. The inspection device for the high-pressure tank member mainly includes an X-ray radiating device and an X-ray detector. The X-ray radiating device radiates X-rays to the high-pressure tank member. The X-ray detector detects X-rays that have passed through the high-pressure tank member. The X-ray radiating device and the X-ray detector constituting the inspection measures are the same as those described above in the embodiment of the inspection method. Therefore, detailed description is omitted.

According to the inspection device of the present embodiment, impurities and voids existing in the high-pressure tank member can be detected by detecting the transmitted X-rays. The high-pressure tank member in which these impurities and the like are detected may be appropriately selected as defective products and eliminated. Further, according to the inspection device of the present embodiment, the liner member may be inspected before the tank is molded. In this case, the liner member can be determined as a defective product before, for example, a reinforcing layer made of a fiber reinforced resin is formed on the liner member. As a result, the fiber reinforced resin is not wasted. In addition, the yield of the manufactured high-pressure tank is improved.

The embodiment of the present invention has been described above with reference to the drawings. In the present invention, for example, the following modified embodiments can be adopted.

(1) In the above embodiment (inspection method embodiment), FIG. 1 is referred to to illustrate a case where a bowl-shaped liner member before joining is inspected. In addition to this, in the present invention, after the two bowl-shaped liner members are joined after the inspection, the inspection may be performed again only on the formed joint portion. As a result, impurities and voids that may occur at the joint site can be detected without leakage.

(2) In the above embodiment, the case where the liner member is inspected is illustrated. In addition to this, the present invention may also inspect the high-pressure tank member after inspecting the liner member and, if necessary, forming a reinforcing layer.

The embodiment of the present invention has been described above. The present invention is not limited to the above embodiments. It should be noted that the above-described embodiment mainly describes one aspect of the present invention having the following configuration.

(1) An inspection method for high-pressure tank members that radiates X-rays from the X-ray radiating device to the high-pressure tank member and inspects the X-rays that have passed through the high-pressure tank member for defects using an X-ray detector. A method for inspecting a high-pressure tank member, wherein the wall surface of one of the high-pressure tank members is arranged between the X-ray radiating device and the X-ray detector.

According to such a configuration, impurities and voids existing in the high-pressure tank member can be detected by detecting the transmitted X-rays. The high-pressure tank member in which these impurities and the like are detected may be appropriately selected as defective products and eliminated. Further, for example, X-rays are radiated from an X-ray radiating device arranged outside a substantially cylindrical high-pressure tank member, and transmitted by an X-ray detector arranged at an opposite position through the entire high-pressure tank member. When detecting the X-rays, the X-rays pass through a plurality of wall surfaces of the high-pressure tank member. In this case, even when the presence of impurities or the like is confirmed by the transmitted X-rays, it is not clear which wall surface the impurities or the like are present on, and the impurities may not be clearly grasped. On the other hand, in the present invention, only one wall surface of the high-pressure tank member is inspected. Therefore, according to the present invention, the presence or absence of impurities can be easily grasped.

(2) The X-ray detector is arranged outside the high-pressure tank member in which a predetermined space is formed, and the X-ray radiating device is arranged inside the high-pressure tank member for the high-pressure tank. The method for inspecting a high-pressure tank member according to (1), wherein X-rays radiated from the inside of the member are detected externally.

According to such a configuration, the X-ray detector is arranged outside the member for the high pressure tank. Therefore, the X-ray detector may be larger than the high-pressure tank member. As a result, the area that can be inspected by one X-ray imaging becomes large, and the inspection time can be shortened. Further, since the X-ray detector is arranged outside the high-pressure tank member, the separation distance between the X-ray detector and the wall surface of the high-pressure tank member can be changed. Therefore, in the present invention, for example, the magnification at the time of X-ray photography can be adjusted according to the size of impurities and the like. As a result, according to the present invention, impurities and the like can be detected more accurately.

(3) The X-ray detector is arranged inside the high-pressure tank member in which a predetermined space is formed, and the X-ray radiating device is arranged outside the high-pressure tank member for the high-pressure tank. The method for inspecting a high-pressure tank member according to (1), which internally detects X-rays emitted from the outside of the member.

According to such a configuration, the X-ray radiating device is arranged outside the member for the high pressure tank. Therefore, the X-ray radiating device may be larger than the high-pressure tank member. As a result, a large-scale X-ray radiating device capable of irradiating a high-dose X-ray can be used, and an image can be acquired with a short-time X-ray irradiation, so that the X-ray inspection time can be shortened. Further, since the X-ray radiating device is arranged outside the high-pressure tank member, the separation distance between the X-ray radiating device and the wall surface of the high-pressure tank member can be changed. Therefore, in the present invention, for example, the magnification at the time of X-ray photography can be adjusted according to the size of impurities and the like. As a result, according to the present invention, impurities and the like can be detected more accurately.

(4) The inspection of the high-pressure tank member according to any one of (1) to (3), wherein the high-pressure tank member has an opening, and the minimum opening length of the opening is 5 cm or less. Method.

According to such a configuration, the high-pressure tank member has a small opening having a minimum opening length of 5 cm or less. Such a member for a high-pressure tank corresponds to a liner member or the like formed into a cylindrical shape, which will be described later, and by inspecting after molding into a cylindrical shape, impurities and voids can be inspected in a state closer to the final product. Can be done.

(5) The method for inspecting a high-pressure tank member according to (4), wherein the X-ray radiating device is inserted through the opening of the high-pressure tank member.

According to such a configuration, only one wall surface can be inspected even for the high-pressure tank member having only a small opening. Therefore, according to the present invention, it is easy to clearly grasp the presence or absence of impurities even in a liner member or the like formed into a cylindrical shape.

(6) The high-pressure tank member is inspected by driving the high-pressure tank member and changing the relative position between the X-ray radiating device and the high-pressure tank member, according to (1) to (5). The method for inspecting high-pressure tank members according to any one.

According to such a configuration, the high-pressure tank member is driven while maintaining the positional relationship between the X-ray radiating device and the X-ray detector. Therefore, X-ray photography can be continuously performed on the high-pressure tank member. As a result, the time required for the inspection can be shortened.

(7) The high-pressure tank member is inspected by driving the X-ray radiating device and changing the relative position between the X-ray radiating device and the high-pressure tank member, according to (1) to (5). The method for inspecting high-pressure tank members according to any one.

According to such a configuration, by driving the X-ray radiating device, the position where the X-ray is radiated with respect to the high-pressure tank member can be precisely controlled. Therefore, for example, even when the high-pressure tank member includes a curved portion, X-rays can be sufficiently emitted to such a curved portion. As a result, according to the present invention, impurities and the like can be detected more accurately.

(8) The method for inspecting a high-pressure tank member according to any one of (1) to (7), wherein the X-ray detector is an indirect conversion type X-ray detector.

With such a configuration, a developing step or the like is not required as compared with the case where, for example, an X-ray film is used. Therefore, the time required for the inspection can be shortened. Further, the indirect conversion type detector has no restrictions such as the usable temperature as compared with the direct conversion type detector. Therefore, the indirect conversion type detector is excellent in handleability.

(9) The method for inspecting a member for a high-pressure tank according to (8), wherein the indirect conversion type X-ray detector includes a cell type scintillator.

According to such a configuration, the detector provided with the cell scintillator has high sharpness. Therefore, according to the present invention, impurities and the like can be detected more accurately.

(10) The method for inspecting a high-pressure tank member according to any one of (1) to (9), wherein the high-pressure tank member is a liner member for a high-pressure tank.

According to such a configuration, by inspecting the liner member in the stage before molding the tank, it can be determined as a defective product before, for example, a reinforcing layer made of a fiber reinforced resin is formed on the liner member. As a result, the fiber reinforced resin is not wasted. In addition, the yield of the manufactured high-pressure tank is improved.

(11) The method for inspecting a high-pressure tank member according to (10), wherein the liner member is made of resin.

According to such a configuration, the liner member is made of resin. Such a liner member is easily affected by deformation and destruction due to impurities and the like, and is an effective application target of the inspection method of the present invention.

(12) The method for inspecting a member for a high-pressure tank according to (4), wherein the resin contains at least one of polyolefin, ethylene-vinyl alcohol copolymer and polyamide.

According to such a configuration, the liner member contains at least one of polyolefin, ethylene-vinyl alcohol copolymer and polyamide. Such a liner member is more susceptible to deformation and destruction due to impurities and the like, and is an effective application target of the inspection method of the present invention.

(13) The inspection step of carrying out the inspection method for the high-pressure tank member according to any one of (1) to (12), the high-pressure tank member determined to be defective in the inspection step, and the high-pressure tank member determined to be non-defective. A method for manufacturing a high-pressure tank member, which includes a sorting step for distinguishing the high-pressure tank member.

According to such a configuration, impurities and voids existing in the high-pressure tank member can be appropriately detected in the inspection process. Further, the high-pressure tank member in which impurities and the like are detected can be sorted and eliminated in the sorting step.

(14) An inspection step for carrying out the inspection method for the high-pressure tank member according to any one of (10) to (12), a liner member determined to be defective in the inspection step, and a liner determined to be non-defective. A method for manufacturing a high-pressure tank, which includes a sorting step for distinguishing members and an outer layer forming step for forming a reinforcing outer layer for a liner member determined to be a non-defective product.

According to such a configuration, impurities and voids existing in the liner member for the high pressure tank can be appropriately detected in the inspection process. Further, the liner member in which impurities or the like are detected can be sorted and eliminated in the sorting step. Therefore, according to the method for manufacturing a liner member of the present invention, only non-defective liner members are selected, and in a subsequent step, for example, a reinforcing layer (outer layer) made of fiber reinforced resin is formed, and a high-pressure tank can be manufactured. As a result, according to the method for manufacturing a liner member of the present invention, the fiber reinforced resin is not wasted for the defective liner member. In addition, the yield of the manufactured high-pressure tank is improved.

(15) An inspection device for carrying out the inspection method for a high-pressure tank member according to any one of (1) to (12), which includes an X-ray radiating device and an X-ray detector, and includes the X-ray. The radiating device emits X-rays to the high-pressure tank member, and the X-ray detector detects X-rays transmitted through the high-pressure tank member, which is an inspection device for the high-pressure tank member.

According to such a configuration, the inspection device includes an X-ray emitting device and an X-ray detector. The X-ray radiating device radiates X-rays to the high-pressure tank member. The X-ray detector detects X-rays that have passed through the high-pressure tank member. Therefore, according to the inspection apparatus of the present invention, impurities and voids existing in the high-pressure tank member can be detected by detecting the transmitted X-rays. The high-pressure tank member in which these impurities and the like are detected may be appropriately selected as defective products and eliminated.

Hereinafter, the present invention will be described in more detail with reference to Examples. The present invention is not limited to these examples.

<Manufacturing liner members for high-pressure tanks>
The resin used in each of the examples described later is a substantially bowl having a substantially cylindrical cylinder portion and a substantially hemispherical dome portion provided at one end of the cylinder portion by injection molding using pellets as a raw material. A liner member for a high-pressure tank was produced. The dimensions of the obtained liner member were such that the diameter of the cylinder portion was 60 cm, the distance from the tip of the substantially cylindrical portion to the center of the cylinder portion in the opposite direction was 50 cm, and the thickness was 5 mm. Separately from this, the resin pellets described in each of the examples described later are similarly injection-molded using a raw material in which 1 wt% undried polyethylene pellets are added, and have the same shape, and polyethylene and voids. A liner member for a high-pressure tank having the above was produced.

<Hydrogen exposure test>
After the liner member was placed in the autoclave, hydrogen gas was injected into the autoclave to a pressure of 30 MPa over 3 minutes, held for 2 hours, and then depressurized over 1 minute until the pressure became normal. After repeating this for 100 cycles as one cycle, the presence or absence of deformation or breakage was visually confirmed at 10 points where the X-ray inspection was performed.

<X-ray inspection>
Unless otherwise specified in Examples and Comparative Examples, Varian's PaxScan2520 was used as an X-ray detector. The X-ray emitting device and the X-ray detector were arranged in the arrangement described in the examples described later, and the liner member was inspected by emitting X-rays under the condition of a tube voltage of 40 kV. Unless otherwise specified, imaging was performed at 10 different locations of the liner members.

<Manufacturing of cell scintillator>
(Ingredients for paste)
The raw materials used to prepare the paste are shown below.
Photosensitive Monomer M-1: Trimethylolpropane Triacrylate Photosensitive Monomer M-2: Tetrapropylene Glycoldimethacrylate Photosensitive Polymer: Copolymer having a mass ratio of methacrylic acid / methyl methacrylate / styrene = 40/40/30 0.4 equivalent of glycidyl methacrylate was added to the carboxyl group of the above (weight average molecular weight 43000, acid value 100).
Binder resin: 100 cP ethyl cellulose photopolymerization initiator: 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butanone-1 (IC369; manufactured by BASF)
Thermal polymerization initiator: V-40 (manufactured by Wako Pure Chemical Industries, Ltd.)
Polymerization inhibitor: 1,6-hexanediol-bis [(3,5-di-t-butyl-4-hydroxyphenyl) propionate])
Ultraviolet absorber solution: Sudan IV (manufactured by Tokyo Ohka Kogyo Co., Ltd.) γ-butyrolactone 0.3% by mass solution Viscosity adjuster: Fronon EC121 (manufactured by Kyoeisha Chemical Co., Ltd.)
Solvent: γ-butyrolactone low softening point glass powder: SiO ₂ 27% by mass, B ₂ O ₃ 31% by mass, ZnO 6% by mass, Li ₂ O 7% by mass, MgO 2% by mass, CaO 2% by mass, BaO 2% by mass %, Al ₂ O ₃ 23% by mass, refractive index (ng) 1.56, glass softening temperature 588 ° C, linear expansion coefficient 70 × 10 ^-7 (K ^-1 ), average particle size 2.3 μm
High softening point glass powder: SiO ₂ 30% by mass, B ₂ O ₃ 31% by mass, ZnO 6% by mass, MgO 2% by mass, CaO 2% by mass, BaO 2% by mass, Al ₂ O ₃ 27% by mass, refractive coefficient (Ng) 1.55, softening temperature 790 ° C., coefficient of thermal expansion 32 × 10 ^-7 (K ^-1 ), average particle size 2.3 μm

(Preparation of glass powder-containing paste)
4 parts by mass of photosensitive monomer M-1, 6 parts by mass of photosensitive monomer M-2, 24 parts by mass of photosensitive polymer, 6 parts by mass of photopolymerization initiator, 0.2 parts by mass of polymerization inhibitor and 12 8.8 parts by mass of the UV absorber solution was dissolved in 38 parts by mass of the solvent by heating at a temperature of 80 ° C. After cooling the obtained solution, 9 parts by mass of a viscosity modifier was added to prepare an organic solution. After adding 30 parts by mass of low softening point glass powder and 10 parts by mass of high softening point glass powder to 60 parts by mass of an organic solution, the mixture was kneaded with a three-roller kneader to prepare a glass powder-containing paste A. ..

(Manufacturing of cell scintillator)
As a base material, a glass plate (PD-200; manufactured by Asahi Glass Co., Ltd.) having a size of 500 mm × 500 mm × 1.8 mm was used. A glass powder-containing paste was applied to the surface of the base material with a die coater so that the drying thickness was 500 μm, and dried to obtain a coating film. Next, the coating film was applied to the coating film using an ultra-high pressure mercury lamp at 750 mJ / cm via a photomask having openings corresponding to the desired pattern (a chrome mask having a pitch of 127 μm, a line width of 20 μm, and a grid-like openings). ^It was exposed with an exposure amount of ² . The coating film after exposure was developed in a 0.5 mass% monoethanolamine aqueous solution, and unexposed portions were removed to obtain a grid-like pre-baking pattern. The obtained grid-like pre-firing pattern was fired in air at 585 ° C. for 15 minutes to obtain a grid-like post-firing pattern. A phosphor obtained by mixing GOS: Tb powder having a particle size of 10 μm with a benzyl alcohol solution of ethyl cellulose was filled in a cell partitioned by a partition wall so as to have a volume fraction of 65%, dried at 120 ° C., and a cell scintillator. A panel was made.

(Example 1)
A liner member was produced using polyamide 6 as the resin. Inside this liner member, L9181-02 manufactured by Hamamatsu Photonics Co., Ltd. was arranged as an X-ray radiating device. Further, the X-ray detector was arranged outside, and the X-ray transmission inspection of the wall surface of 1 was performed. The inspection was performed by fixing the X-ray radiating device and the X-ray detector and rotating the liner member around the X-ray detector.

(Comparative Example 1)
In Example 1, the inspection was carried out in the same manner as in Example 1 except that the X-ray emitting device was arranged outside the liner member and observed through the wall surface of 2. The inspection was continuously performed by driving the liner member and changing the relative position between the X-ray emitting device and the liner member.

(Example 2)
In Example 1, the inspection was carried out in the same manner as in Example 1 except that the scintillator inside the X-ray detector was replaced with the cell type scintillator.

(Example 3)
In Example 1, the inspection was carried out in the same manner as in Example 1 except that 100 parts by weight of polyamide 6 and 5 parts by weight of polyamide 610 resin were melt-kneaded as the resin.

(Example 4)
In Example 1, the same inspection as in Example 1 was carried out except that 100 parts by weight of polyamide 6 and 20 parts by weight of maleic anhydride-modified ethylene / 1-butene copolymer were melt-kneaded as the resin. went.

(Example 5)
Using polyamide 6 as the resin, 20 substantially bowl-shaped liner members for high-pressure tanks having an opening having a minimum opening length of 4.5 cm were produced. After that, two substantially bowl-shaped liner members were joined to prepare ten cylindrical liner members having a cylinder diameter of 60 cm and a length in the cylindrical axis direction of 100 cm. A rod-shaped X-ray source having a diameter of 3.5 cm, a length of 110 cm, an X-ray generating portion 5 cm from one end of the rod-shaped portion, and 105 cm from the other end is provided from one of the openings of these liner members. , 55 cm from the end side having the X-ray generating part nearby, and the focal point of the X-ray tube of the X-ray emitting device was placed on the plane including the substantially circular joint part. In addition, the X-ray detector was placed outside, and an X-ray transmission inspection was performed around the welded portion on the wall surface of 1. The inspection was performed by fixing the X-ray radiating device and the X-ray detector and rotating the liner member around the X-ray detector.

(Example 6)
In Example 5, a rod-shaped X-ray source was inserted 50 cm from the end side having an X-ray generating portion nearby and arranged at a position 5 cm away from a plane including a substantially circular joint portion. The inspection was performed in the same manner as in 5.

(Example 7)
Using polyamide 6 as the resin, 20 substantially bowl-shaped liner members for high-pressure tanks having an opening having a minimum opening length of 4.5 cm were produced. After that, two substantially bowl-shaped liner members were joined to prepare ten cylindrical liner members having a cylinder diameter of 60 cm and a length in the cylindrical axis direction of 100 cm. From one of the openings of these liner members, an X-ray detector having a width of 4 cm is arranged on a plane including a joint where the center of the effective detection range of the detector is substantially circular and on the central axis of the liner. As shown, 50 cm was inserted. Further, outside the liner member, L9181-02 manufactured by Hamamatsu Photonics Co., Ltd. is arranged as an X-ray radiating device so that the X-ray tube focus comes at a position 5 cm from the liner wall surface, and the welded portion of the wall surface of 1. Regarding the periphery, X-ray transmission inspection was performed at 100 different locations of the liner members. The inspection was performed by fixing the X-ray radiating device and the X-ray detector and rotating the liner member around the X-ray detector.

By the inspection in Example 1, only the liner member having polyethylene impurities and voids, voids were detected in 3 out of 10 photographed places, and polyethylene impurities were detected in 2 places. When the hydrogen exposure test was carried out on the liner member after the inspection, deformation and fracture were observed only in the vicinity of five abnormal points detected by the X-ray image in the liner member having polyethylene impurities and voids.

According to the inspection in Comparative Example 1, only the liner member having polyethylene impurities and voids was detected with voids in one of the ten photographed locations and polyethylene impurities in one location, but the image quality was unclear. When the above hydrogen exposure test was carried out on the liner member after the inspection, deformation or breakage was observed on one of the two wall surfaces where abnormal points were detected on the X-ray image in the liner member having polyethylene impurities and voids. However, deformation and destruction were observed even in some places where no abnormal points were observed in the X-ray image, which was defective.

By the inspection in Example 2, only the liner member having polyethylene impurities and voids, voids were detected in 3 out of 10 photographed places, and polyethylene impurities were detected in 3 places. At this time, since the X-ray detector provided with the cell type scintillator was used in the third embodiment, the acquired X-ray radiation image was very clear. When the hydrogen exposure test was carried out on the liner member after the inspection, deformation and fracture were observed only in the vicinity of the six abnormal points detected in the X-ray image in the liner member having polyethylene impurities and voids.

By the inspection in Example 3, only the liner member having polyethylene impurities and voids, voids were detected in 2 out of 10 photographed places, and polyethylene impurities were detected in 3 places. When the hydrogen exposure test was carried out on the liner member after the inspection, deformation and fracture were observed only in the vicinity of 6 abnormal points detected by the X-ray image in the liner member having polyethylene impurities and voids, and in particular, voids were observed. Major damage that led to serious damage to the tank was confirmed in the area including, indicating the importance of conducting inspection by this inspection method.

By the inspection in Example 4, only the liner member having polyethylene impurities and voids, voids were detected in 3 out of 10 photographed places, and polyethylene impurities were detected in 2 places. When the above hydrogen exposure test was carried out on the liner member after the inspection, deformation and fracture were observed only in the vicinity of 6 abnormal points detected by the X-ray image in the liner member having polyethylene impurities and voids, and in particular, polyethylene was observed. Large deformations that lead to serious damage to the tank were confirmed at locations containing impurities, demonstrating the importance of conducting inspections using this inspection method.

By the inspection in Example 5, voids were detected in two of the ten images taken in the welded portion of one of the ten cylindrical liner members. When the hydrogen exposure test was carried out on the liner member after the inspection, deformation and fracture were observed only at two abnormal points detected by the X-ray image in the liner member in which voids were detected in the welded part. ..

By the inspection in Example 6, voids were detected in one of the ten cylindrical liner members in one of the ten welded parts. When the hydrogen exposure test was carried out on the liner member after the inspection, deformation and fracture were observed at one abnormal point detected by the X-ray image in the liner member in which voids were detected in the welded portion. In addition, even in one place where no void was detected, minute deformation was observed within a range that did not affect the performance of the tank.

By the inspection in Example 7, voids were detected in two of the 100 photographed locations in the welded portion of one of the ten cylindrical liner members. At this time, in the seventh embodiment, the X-ray emitting device is arranged near the liner wall surface, and the X-ray detector is arranged at a position away from the liner wall surface to perform magnified imaging. Therefore, the acquired X-ray emission image is obtained. , Was very clear. When the hydrogen exposure test was carried out on the liner member after the inspection, deformation and fracture were observed only at two abnormal points detected by the X-ray image in the liner member in which voids were detected in the welded part. ..

1, 1a Liner member 11 Cylinder part 12 Dome part 2 X-ray radiator 3 X-ray detector 4 Radiation range 5 Opening

Claims (10)

This is an inspection method for high-pressure tank members, which emits X-rays from the X-ray radiating device to the high-pressure tank member and inspects the X-rays that have passed through the high-pressure tank member for defects using an X-ray detector.
The high-pressure tank member is a liner member for a high-pressure tank.
The liner member is made of resin and
An inspection was performed in a state where the wall surface of 1 of the high-pressure tank member was arranged between the X-ray radiating device and the X-ray detector.
The high-pressure tank member has an opening and has an opening.
The minimum opening length of the opening is 5 cm or less.
The X-ray radiating device is inserted through the opening of the high-pressure tank member.
The X-ray radiating device is a rod-shaped inspection method for a member for a high-pressure tank. The X-ray detector is arranged outside the high-pressure tank member having a predetermined space formed inside, the X-ray radiating device is arranged inside the high-pressure tank member, and the inside of the high-pressure tank member. The method for inspecting a member for a high-pressure tank according to claim 1, wherein X-rays emitted from the vehicle are detected externally. The high-pressure tank member according to claim 1 or 2 , which inspects the high-pressure tank member by driving the high-pressure tank member and changing the relative position of the X-ray radiating device and the high-pressure tank member. Inspection method. The high-pressure tank member according to claim 1 or 2 , which inspects the high-pressure tank member by driving the X-ray radiating device and changing the relative position between the X-ray radiating device and the high-pressure tank member. Inspection method. The method for inspecting a member for a high-pressure tank according to any one of claims 1 to 4 , wherein the X-ray detector is an indirect conversion type X-ray detector. The method for inspecting a member for a high-pressure tank according to claim 5 , wherein the indirect conversion type X-ray detector includes a cell type scintillator. The method for inspecting a member for a high-pressure tank according to any one of claims 1 to 6 , wherein the resin contains at least one of polyolefin, ethylene-vinyl alcohol copolymer, and polyamide. An inspection step for carrying out the inspection method for the high-pressure tank member according to any one of claims 1 to 7 , a high-pressure tank member determined to be defective in the inspection step, and a high-pressure tank determined to be non-defective. A method for manufacturing a member for a high-pressure tank, which includes a sorting step for distinguishing the member from the member. An inspection step for carrying out the inspection method for a high-pressure tank member according to any one of claims 1 to 7 , a liner member determined to be a defective product in the inspection step, and a liner member determined to be a non-defective product. A method for manufacturing a high-pressure tank, which includes a sorting step for distinguishing and an outer layer forming step for forming an outer layer for reinforcement with respect to a liner member determined to be a non-defective product. An inspection device for carrying out the inspection method for a high-pressure tank member according to any one of claims 1 to 7 , wherein the X-ray radiating device includes an X-ray radiating device and an X-ray detector. An inspection device for high-pressure tank members, which emits X-rays to the high-pressure tank member, and the X-ray detector detects X-rays that have passed through the high-pressure tank member.

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