JP6977541B2 - Manufacturing method of high pressure gas tank - Google Patents

Description

The present invention relates to a method for manufacturing a high pressure gas tank.

As a method for manufacturing a high-pressure gas tank, a method of attaching a protective layer as a dome portion surrounding member to a tank having a cylindrical cylinder portion and a hemispherical dome portion located at both ends of the cylinder portion is disclosed (patented). See Document 1). This manufacturing method includes a step of attaching a positioning jig for attaching the protective layer to the dome portion to the tank, and a step of positioning the protective layer on the dome portion by the positioning jig. In this manufacturing method, a reinforcing layer as a fiber reinforced resin layer made of a thermosetting resin is formed on the outer peripheral surfaces of the cylinder portion and the dome portion. Next, as shown in FIG. 10, a curing step of heating the tank to cure the reinforcing layer is performed, and then a curing step of quenching the tank to cure the reinforcing layer is performed. In the curing step by quenching, dew condensation water adheres to the surface of the tank, so a dew condensation water drying step is performed in which the dew condensation water is wiped off and the surface of the tank is dried. Then, a protective layer attaching step of adhering the protective layer to the dome portion of the dried tank with an adhesive is performed, and the high-pressure gas tank is completed.

Japanese Unexamined Patent Publication No. 2014-190495

However, in the method for manufacturing a high-pressure gas tank described in Patent Document 1, if the tank is rapidly cooled in order to shorten the cooling time in the curing step, dew condensation water adheres to the surface of the tank. Therefore, there is a problem that it is necessary to provide a dew condensation water drying step of wiping and drying the dew condensation water before adhering the protective layer to the dome portion in the protective layer attaching step.

In addition, the surface of the tank is uneven during the curing process by heating, but in order to reliably adhere the protective layer to the uneven surface, it is adhered so as to fill the unevenness and make it a uniform surface to secure the adhesive area. There is a problem that it becomes necessary to apply a thick agent or polish the protrusions. If the adhesive is applied thickly, it takes time for the inside to harden, and there is a problem that the pressure holding by the mechanism for pressure holding the protective layer becomes relatively long. Further, when polishing the convex portion, there is a problem that the polishing process is increased.

The present invention has been made to solve such a problem, and to provide a method for manufacturing a high-pressure gas tank capable of shortening the cooling time in the tank curing step and shortening the bonding time of the protective layer. Make it an issue.

The method for manufacturing a high-pressure gas tank according to the present invention is a method for manufacturing a high-pressure gas tank in which a protective layer is attached to a tank having a reinforcing layer, and the tank is rapidly cooled to generate dew condensation water on the surface of the reinforcing layer. It is characterized in that the protective layer is adhered to the reinforcing layer by a moisture-curable adhesive in a state where the dew condensation water is accumulated in the concave portion on the surface of the reinforcing layer.

In the method for manufacturing a high-pressure gas tank according to the present invention, the tank is rapidly cooled to generate dew condensation water on the surface of the reinforcing layer, and the dew condensation water is accumulated in the recesses on the surface of the reinforcing layer. As a result, the protective layer is adhered to the reinforcing layer, so that the curing of the adhesive can be promoted by the dew condensation water. Therefore, it is possible to shorten the time required for hardening by cooling the reinforcing layer of the tank and mounting of the protective layer.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a method for manufacturing a high-pressure gas tank capable of shortening the cooling time in the tank curing step and shortening the bonding time of the protective layer.

It is a figure of the tank manufactured by the manufacturing method of the high pressure gas tank which concerns on embodiment of this invention, FIG. 1 (a) shows the exploded perspective view of the tank, and FIG. 1 (b) shows the perspective view of a tank. 1 (c) shows a cross-sectional view of the protective layer. The process drawing which shows the manufacturing method of the high pressure gas tank which concerns on embodiment of this invention. FIG. 3A is a perspective view of a tank in which a reinforcing layer is formed by the method for manufacturing a high-pressure gas tank according to an embodiment of the present invention, and FIG. 3A shows a reinforcing layer whose outer peripheral portion is formed by helical winding. b) shows a reinforcing layer whose outer peripheral portion is formed by hoop winding. The graph which shows the relationship between the elapsed time of the hardening process and the temperature in the manufacturing method of the high pressure gas tank which concerns on embodiment of this invention. FIG. 5A is a view of the surface of the reinforcing layer after curing the tank applied to the method for manufacturing a high-pressure gas tank according to the embodiment of the present invention, and FIG. 5A shows a side view of the tank having the cured reinforcing layer. 5 (b) shows a side view of the tank showing the uneven state of the hardened reinforcing layer. The schematic diagram which shows the positional relationship and the wind speed of a tank and a cold air blower in the hardening process in the manufacturing method of the high pressure gas tank which concerns on embodiment of this invention. FIG. 7A is a partial cross-sectional view and a partially enlarged cross-sectional view of a tank applied to the method for manufacturing a high-pressure gas tank according to an embodiment of the present invention. FIG. FIG. 7B shows a state in which a protective layer coated with an adhesive is attached to the outer peripheral surface of the reinforcing layer. It is a figure of the tank applied to the manufacturing method of the high pressure gas tank which concerns on embodiment of this invention, FIG. 8 (a) shows the state which the adhesive was applied to the protective layer, and FIG. It shows the state where the protective layer is pressed and held in the tank by the mechanism. 9 (a) is a diagram illustrating the adhesive strength applied to the method for manufacturing a high-pressure gas tank according to an embodiment of the present invention, and FIG. 9 (a) shows a schematic diagram of a tensile test of the adhesive strength, and FIG. 9 (b) shows. Shows a graph showing the relationship between humidity and adhesive strength. A process chart of a conventional high-pressure gas tank manufacturing method.

The manufacturing method of the high pressure gas tank 10 according to the embodiment to which the manufacturing method of the high pressure gas tank according to the present invention is applied will be described with reference to the drawings.

First, the configuration of the high-pressure gas tank 10 will be described. As shown in FIGS. 1 (a), 1 (b), and 1 (c), the high-pressure gas tank 10 includes a tank 11, bases 12, 13 and a reinforcing layer 14 formed on the outer peripheral surface of the tank 11. , It is composed of a pair of protective layers 15. The high-pressure gas tank 10 has a property of making it difficult for gas to permeate, a so-called gas barrier property, and is configured to be filled with a relatively high-pressure gas such as hydrogen.

The tank 11 is made of a cylindrical hollow container, and is made of carbon fiber reinforced plastics (CFRP: Carbon Fiber Reinforced Plastics, hereinafter referred to as CFRP) in which plastic such as polyamide resin (PA) is reinforced with carbon fiber. ing. The material of the tank 11 may be an engineering plastic or a metal material having high mechanical strength such as so-called nylon (registered trademark).

The tank 11 has a cylinder portion 16 and a pair of dome portions 17. The cylinder portion 16 is formed in a cylindrical shape, and each dome portion 17 is formed of a hollow substantially hemisphere and is integrally formed with the cylinder portion 16. Each dome portion 17 has a base mounting portion (not shown), and the bases 12 and 13 are mounted on the base mounting portion.

The base 12 is made of a metal material and protrudes in the axial direction of the tank 11 from the dome portion 17 formed in a substantially hemispherical shape. Like the base 12, the base 13 is made of a metal material and protrudes in the axial direction of the tank 11 from the dome portion 17 formed in a substantially hemispherical shape.

The reinforcing layer 14 is formed by winding the fiber bundle F around the outer peripheral surface of the tank 11. The fiber bundle F is formed of plastic such as epoxy resin (EP) reinforced with glass fiber (GFRP: Glass Fiber Reinforced Plastics). The material of the reinforcing layer 14 may be a composite material in which fibers such as carbon fiber and aramid fiber (Aromatic Polyamide Fiber) are put in plastic to improve the strength.

The fiber bundle F is composed of a fiber bundle in which several thousand to tens of thousands of so-called multifilaments, which are obtained by twisting dozens of single fibers into one thread, are bundled. The reinforcing layer 14 is formed, for example, by a filament winding device (Filament Winding Process, hereinafter referred to as a FW device) (not shown).

In this FW device, a thick fiber bundle F is stretched and thinned, and a sweet twist is applied to form a blister yarn, and the so-called cruising yarn (roving such as glass roving) that has been wound is impregnated with a resin, or the resin is applied. A manufacturing device that applies tension to the impregnated roving yarn and continuously winds it around the workpiece. The resin to be impregnated in the crude yarn is made of, for example, a thermosetting resin such as an epoxy resin (EP), a polyester resin (PE) or a polyamide resin (PA). According to this FW method, the strength in the axial direction and the circumferential direction of the workpiece can be adjusted by adjusting the angle at the time of winding.

A method for manufacturing the high-pressure gas tank 10 according to the present embodiment will be described. As shown in FIG. 2, the method for manufacturing the high-pressure gas tank 10 includes a tank, a base and a protective layer manufacturing step, a reinforcing layer forming step, a curing step by heating, and a curing by quenching and a protective layer affixing step. Has been done. Each step is performed in sequence. The curing and protective layer affixing steps of the present embodiment by quenching constitute the method for manufacturing a high-pressure gas tank according to the present invention.

In the tank, base and protective layer manufacturing step, the tank 11, the base 12, 13 and the pair of protective layers 15 are manufactured (step S1). The tank 11 is divided at the central portion in the longitudinal direction, and the tank on one side having the cylinder portion and the dome portion 17 and the tank on the other side having the cylinder portion and the dome portion 17 like the tank on one side are separated by CFRP. Each is produced by molding. Further, the bases 12 and 13 are manufactured by metal processing such as mold casting and cutting, respectively.

Next, the base 12 is inserted into the through hole of the prepared tank on one side, and the tank on one side and the base 12 are fitted to each other. Further, the base 13 is inserted into the through hole of the manufactured tank on the other side, and the tank on the other side and the base 13 are fitted to each other. Next, the one end of the cylinder of the tank on one side to which the base 12 is mounted and the other end of the cylinder of the tank of the other side to which the base 13 is mounted are opposed to each other. Assemble the tank on one side and the tank on the other side so that they are aligned and their axes are aligned with each other.

The assembled tank on one side and the tank on the other side are joined by a joining means such as laser fusion. By this joining, the tank on one side and the tank on the other side are integrated, and the tank 11 to which the bases 12 and 13 are attached is manufactured.

Each protective layer 15 is made of a rubber material such as urethane rubber, nitrile rubber, or fluororubber, and is manufactured in the same shape as the dome portion 17 of the tank 11 as shown in FIGS. 1 (a) and 1 (c). Ru. The protective layer 15 has a through hole 15a in the central portion, and is configured so that the bases 12 and 13 are inserted when the protective layer 15 is attached to the dome portion 17. Further, the inner peripheral surface 15b of the protective layer 15 is formed in a curved surface shape similar to the outer peripheral surface of the dome portion 17, and when attached to the dome portion 17, the inner peripheral surface 15b forms the outer peripheral surface of the dome portion 17. It is configured to cover.

In the reinforcing layer forming step, a plurality of bobbins around which the fiber bundle F is wound are set in the FW device, the fiber bundle F unwound from the bobbins is set in each component of the FW device, and the FW device is operated. The fiber bundle F is wound around the outer peripheral surface of the tank 11 by the FW device to form the reinforcing layer 14 (step S2). The FW device includes a fiber bundle winding mechanism (not shown) having a support portion for supporting the bases 12 and 13 of the tank 11 and a rotation drive portion for rotating the tank 11 around the axis. The fiber bundle winding mechanism is configured to wind the fiber bundle F around the outer peripheral surface of the tank 11 in cooperation with the reciprocating movement of the fiber bundle F in the axial direction and the rotation of the tank 11.

The fiber bundle winding mechanism controls the moving speed (m / sec) of the fiber bundle F in the axial direction of the tank 11 and the rotation speed (rpm) of the tank 11 by a control unit (not shown), so that the tank 11 has a fiber bundle winding mechanism. The winding method of the fiber bundle F can be changed to helical winding or hoop winding.

As shown in FIG. 3A, the helical winding is a winding method in which the winding locus of the fiber bundle F intersects the axis CL of the tank 11 at a low angle θ of, for example, about 10 ° to 30 °. The bundle F is repeatedly spirally wound over the cylinder portion 16 of the tank 11 and the entire pair of dome portions 17.

As shown in FIG. 3B, the hoop winding is a winding method in which the winding locus of the fiber bundle F intersects the axis CL of the tank 11 at an angle close to a right angle of, for example, about 90 °. Is repeatedly wound around the outer peripheral surface of the cylinder portion 16 of the tank 11.

In the curing step by heating, the reinforcing layer 14 is cured (step S3). The reinforcing layer 14 is cured by a heating device (not shown) such as a heating furnace or an induction heating coil that induces high frequency induction heating, and the thermosetting resin such as the epoxy resin in the reinforcing layer 14 is cured by the heat treatment.

As shown in FIG. 4, the heat treatment is performed so that the relationship between the elapsed time (min) and the temperature rises at a constant rate from the start of heating to the predetermined temperature (° C.) indicated by point a. Points a to b are held at a predetermined temperature for a predetermined time. From point b to the glass transition point indicated by Tg, the glass is slowly cooled so that the relationship between the elapsed time (min) and the temperature gradually decreases at a constant rate. The relationship between the elapsed time (min) and the temperature is controlled so that the slow cooling from the point b to Tg does not affect the quality. That is, the slow cooling rate is controlled. The predetermined temperature and the predetermined time are appropriately selected based on the setting specifications such as the structure, size, and material of the tank 11 and the reinforcing layer 14, and the data such as experimental values.

In the curing step by heating, when the reinforcing layer 14 is cured by heating, the fiber bundle F wound around the outer peripheral surface of the reinforcing layer 14 becomes a reinforcing layer having innumerable uneven shapes as shown in FIG. 5A. The mechanical strength of the tank 11 is increased. As shown in FIG. 5B, the innumerable uneven shapes have a convex portion having a height of about 1 mm to 5 mm in the region surrounded by the broken line square to which the protective layer 15 is attached, that is, the protective layer 15 is attached. It has become.

In the curing by quenching and the step of attaching the protective layer, the reinforcing layer 14 is quenched after the curing step by heating (step S4). As shown in FIG. 4, when the slow cooling in the curing step by heating is completed at Tg, rapid cooling is started. In quenching, the temperature is lowered at a rate faster than the slow cooling rate, and the cooling time can be shortened. The cooling rate does not affect the quality, so it cools as quickly as possible.

Specifically, the quenching is performed by air cooling using the cold air blown from the nozzle 20a of the cold air blower 20 shown in FIG. The cold air blower 20 is arranged so that the distance from the outer peripheral surface of the tank 11 to the nozzle 20a is about 200 mm, and is adjusted so that the cold air blower 20 is blown to the outer peripheral surface of the reinforcing layer at a wind speed (m / s) of about 20 m / s. Will be done. The tank 11 is rotated at a speed of 1 rpm to 5 rpm around the axis so that the cold air from the cold air blower 20 hits the entire outer peripheral surface of the reinforcing layer 14, and is cooled uniformly as a whole.

As shown in FIG. 7A, dew condensation water W adheres to the outer peripheral surface of the reinforcing layer 14 due to rapid cooling, and the dew condensation water W collects in the recess 14a. The dew condensation water W adhering to the convex portion 14b of the portion surrounded by the broken line square is blown off by the cold air blown from the nozzle 20a of the cold air blower 20, and the convex portion 14b dries. Since the dew condensation water W collected in the concave portion 14a is hard to be hit by cold air, the state of being accumulated in the concave portion 14a is maintained without being blown off by air cooling.

Next, as shown in FIG. 8A, each protective layer 15 is placed on the adhesive coating table T, and the adhesive 40 is applied to each of a plurality of locations on the inner peripheral surface 15b of the protective layer 15. The adhesive 40 is a moisture-curable type that cures by reacting with moisture in the air, and is made of, for example, a cyanoacrylate-based adhesive, a silicone rubber-based adhesive, or a modified acrylic silicone. Each protective layer 15 coated with the adhesive 40 is set in the pressure holding mechanism 30.

Then, as shown in FIG. 8B, the protective layer 15 is attached to the dome portion 17 of the tank 11, and is pressure-held by the pressure-holding mechanism 30. As shown in FIG. 7B, the adhesive 40 applied to each protective layer 15 ensures a good adhesive interface between the surface of the adhesive 40 and the convex portion on the surface of the reinforcing layer 14. The protective layer 15 and the reinforcing layer 14 are bonded to each other by the adhesive 40. That is, the protective layer 15 is attached to the reinforcing layer 14. When the protective layer 15 is attached to the reinforcing layer 14, the adhesive 40 is humidified by the dew condensation water W accumulated in the recess 14a of the reinforcing layer 14, as shown by the arrow in FIG. 7B, and the curing is promoted. Ru.

The effect of the manufacturing method of the high-pressure gas tank 10 according to the embodiment configured as described above will be described.

The method for manufacturing the high-pressure gas tank 10 according to the present embodiment includes a curing step by heating (step S3), a curing by quenching, and a protective layer affixing step (step S4). When the tank 11 is rapidly cooled by the curing step by heating and the curing by quenching and the protective layer attaching step, dew condensation water W is generated on the surface of the reinforcing layer 14, and the generated dew condensation water W is the recess 14a on the surface of the reinforcing layer 14. Accumulate in. On the other hand, the dew condensation water W adhering to the convex portion 14b on the surface of the reinforcing layer 14 is blown off by the cold air of the cold air blower 20. The moisture-curable adhesive 40 is applied in a state where the dew condensation water W is accumulated in the concave portion 14a of the reinforcing layer 14 and the dew condensation water W of the convex portion 14b of the reinforcing layer 14 is blown off. The effect that a good adhesive interface is secured between the convex portion 14b on the surface of the reinforcing layer 14 and the convex portion 14b can be obtained. Further, the surface of the adhesive 40 has an effect that its curing is promoted by the moisture of the dew condensation water W accumulated in the recess 14a of the reinforcing layer 14.

Adhesive strength (N) of the adhesive 40 in the method for manufacturing the high-pressure gas tank 10 according to the present embodiment.
In order to confirm that, the adhesive strength 40 of the adhesive 40 made of modified acrylic silicone was tested as follows. The test method was carried out based on JISK6833 (adhesive-general test method-Part 1: how to obtain basic characteristics). First, as shown in FIG. 9A, a test piece TP bonded with the adhesive 40 was prepared, humidified and heated in a constant temperature and humidity chamber, and then subjected to a tensile test to obtain humidity (%) and adhesive strength (%). The relationship of N) was evaluated.

The test piece TP was produced by preparing two aluminum plates Al having a width of 25 mm, a length of 100 mm, and a thickness of 1.6 mm, applying an adhesive 40, and adhering the two aluminum plates Al. The thickness of the adhesive 40 was 1 mm, and the coating range was 25 mm × 40 mm. The produced test piece TP was humidified and heated in a constant temperature and humidity chamber to be cured. The curing time was 10 min. Tensile test by pulling one aluminum plate Al in the direction of the arrow shown in FIG. 9A and pulling the other aluminum plate Al in the direction opposite to that of one aluminum plate Al at a tensile speed (1 mm / min) after curing. Was done.

FIG. 9B is a graph showing the adhesive strength after the adhesive 40 is cured for 10 minutes after bonding, and the horizontal axis shows the humidity (%) and the vertical axis shows the adhesive strength (N). According to this graph, the adhesive strength is about 10N at a humidity of 30%, but the adhesive strength is 30N at a humidity of 60%. As shown in the graph, the humidity and the adhesive strength are in a proportional relationship, and as the humidity increases, the adhesive strength also increases linearly. As shown in this graph, by humidifying the adhesive 40, the target adhesive strength can be achieved in a short time of about 10 minutes, and the sticking time of the protective layer 15 can be shortened.

In the method for manufacturing the high-pressure gas tank 10 according to the present embodiment, the adhesive 40 is humidified by the dew condensation water W adhering to the surface of the reinforcing layer 14 in the curing by quenching and the step of attaching the protective layer, so that the humidity of the adhesive 40 The effect is that the adhesive strength is increased and the curing speed is also increased.

In the conventional method for manufacturing a high-pressure gas tank, when dew condensation water adheres to the surface of the tank due to rapid cooling, there is a problem that the number of steps is increased because the dew condensation water is wiped off and dried in the dew condensation water drying step. Further, there is a problem that it is necessary to apply a thick adhesive or polish the convex portion so as to fill the unevenness generated on the surface in the curing step by heating to make the surface uniform and secure the adhesive area. In addition, if the adhesive is thick, it takes time for the inside to harden, and there is a problem that the pressure holding by the mechanism that pressurizes and holds the protective layer becomes relatively long. There was a problem that the number increased.

In the method for manufacturing the high-pressure gas tank 10 according to the present embodiment, the curing step by quenching and the step for attaching the protective layer can be performed in one step, and the problem in the conventional method for manufacturing the high-pressure gas tank can be solved. Therefore, it is possible to obtain the effect that the cooling time in the tank curing process can be shortened and the bonding time of the protective layer can be shortened.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various designs are designed without departing from the spirit of the present invention described in the claims. You can make changes.

10 ... High pressure gas tank, 11 ... Tank, 12, 13 ... Mouthpiece, 14 ... Reinforcing layer, 14a ... Concave, 14b ... Convex part, 15 ... Protective layer, 15a ... .. Through hole, 15b ... inner peripheral surface, 16 ... cylinder part, 17 ... dome part, 20 ... cold air blower, 20a ... nozzle, 30 ... pressure holding mechanism, 40・ ・ ・ Adhesive, W ・ ・ ・ Condensed water

Claims (1)

A method for manufacturing a high-pressure gas tank in which a protective layer is attached to a tank having a reinforcing layer.
A fiber bundle impregnated with a thermosetting resin is wound around the outer peripheral surface of the tank to form a reinforcing layer.
The reinforcing layer is heat-cured to form a plurality of concave portions and convex portions on the surface of the reinforcing layer.
Cold air is blown onto the outer peripheral surface of the reinforcing layer to lower the temperature of the reinforcing layer to cause dew condensation on the surface of the reinforcing layer, and the dew condensation water adhering to the plurality of convex portions of the plurality of irregularities is discharged by the cold air. It is assumed that the dew condensation water is accumulated in the plurality of recesses by skipping.
A moisture-curable adhesive is applied to the surface of the protective layer facing the surface of the reinforcing layer.
A method for manufacturing a high-pressure gas tank, which comprises adhering the protective layer to the reinforcing layer with the adhesive.

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