JP2000193194A - Pressure vessel and method of manufacturing the same - Google Patents

Abstract

(57) [Problem] To provide a pressure-resistant container having good inner shell durability and a method for producing the same. An inner shell (2) is rotated, and a filament (81) impregnated with a thermosetting resin is sent out from a filament supply device (80) and wound around the outer periphery of the inner shell (2). After applying helical winding and tape winding to a predetermined thickness, heat treatment is applied to the inner shell 2
The thermosetting synthetic resin adhered to the filament is cured to form an outer shell. The linear body 37 is removed from the groove 36 of the base 6, and the filling material is filled into the gap 90 through the groove 36.
The filling material is then cured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to various compressed gases such as CNG (compressed natural gas), LNG (liquefied natural gas), and LNG.
The present invention relates to a pressure vessel for filling various liquefied gases such as PG (liquefied petroleum gas) and other various pressurized substances, and a method for producing the same.

[0002]

2. Description of the Related Art As a method of manufacturing a pressure-resistant container used for accommodating CNG or the like, an inner shell made of a synthetic resin that does not allow CNG or the like to permeate, and an FRP (fiber reinforced resin) reinforced outer layer satisfying a pressure resistance standard of 600 kg / cm ² are used. And an outer shell composed of layers.

In order to manufacture this pressure-resistant container, first, the inner shell is formed of a synthetic resin by a rotational molding method or the like. A die is attached to the center of the end plate portion of the inner shell together with or after the inner shell is formed. After that, a helical winding and a hoop winding of a reinforcing fiber such as carbon to which an epoxy resin or the like is adhered to the outer periphery of the inner shell is formed by winding and forming an FRP reinforcing layer.
The inner shell and the FRP reinforcing layer are placed in, for example, a thermostat at about 80 ° C., and the resin of the FRP reinforcing layer is cured by heating to form an outer shell.

When the epoxy resin is cured by heating, the inner shell is also heated to about 90 ° C. by the heat given from the thermostat and the self-heating caused by the curing reaction of the epoxy resin. At this time, the thermal expansion coefficient of the inner shell made of synthetic resin is larger than that of the outer shell. For example, inner diameter 220mm, inner law length 900mm
In the case of, the inner shell alone extends 9 mm in a constant temperature bath at about 80 ° C. In fact, since there is an FRP reinforcing layer (outer shell), it is restrained by the carbon fiber of the FRP reinforcing layer, and rather the minus of carbon fiber Linear expansion coefficient (-0.38 × 10
⁻⁶ / ° C.), the total length immediately after curing at about 90 ° C. becomes minus about 0.02 mm.

Then, when the inner and outer shells cool,
The inner shell made of a synthetic resin has a large thermal expansion coefficient and therefore contracts greatly, while the outer shell extends about 0.02 mm due to the negative linear expansion coefficient of the carbon fiber. Due to this difference in shrinkage, a gap is formed between the inner shell and the outer shell over substantially the entire area. Since this difference in shrinkage is greater in the longitudinal direction than in the circumferential direction of the inner shell, a particularly large gap is generated in the end plate portion of the pressure-resistant container.

[0006] CNG is added to the pressure-resistant container having such a gap.
When filled, the inner shell made of synthetic resin extends until it comes into contact with the FRP reinforcing layer (outer shell) due to the high internal pressure caused by CNG, and the durability of the pressure-resistant container, especially the inner shell, is reduced.

Japanese Patent Application Laid-Open No. Hei 10-231998 describes that an elastomer, rubber, or a soft adhesive is injected into the gap to fill the gap.

[0008]

When a soft material such as an elastomer, rubber or a soft adhesive is filled in the above-mentioned space, when the inner pressure of the inner shell is large, the material is deformed so as to be compressed and contracted. The inner shell may also be deformed, causing material fatigue in the inner shell.

In Japanese Patent Application Laid-Open No. Hei 10-231998, a plug having a passage for a filling material is screwed into a base for filling the filling material, and the plug hole and the hole of the base face each other. However, it is difficult to align the hole of the plug with the hole of the base, resulting in poor working efficiency.

An object of the present invention is to provide a pressure-resistant container having a hard packed layer and a method of manufacturing the pressure-resistant container capable of efficiently manufacturing the pressure-resistant container.

[0011]

The pressure vessel of the present invention comprises an inner shell made of a synthetic resin, an outer shell covering the inner shell, and a filling layer filled between the inner shell and the outer shell. The pressure vessel has a filling layer made of a hard material.

In such a pressure-resistant container, since the filling layer is hard, even when the internal pressure is large, the deformation of the inner shell is extremely small, and the durability of the inner shell is good.

When the filling layer is formed of a foamed material, the material is easily filled into every corner of the void.

According to the method for manufacturing a pressure vessel of the present invention, a step of forming an inner shell of a synthetic resin, a step of forming an outer shell covering an outer surface of the inner shell, and a gap between the inner shell and the outer shell are provided. And filling the filling material with a material that becomes hard after curing as the filling material. In this case, expansion of the gap (diameter reduction and contraction of the inner shell) is prevented by applying an inner pressure to the inner shell when filling the material.

In this manufacturing method, a groove for material filling may be provided on the outer peripheral surface of the die inserted at the end of the pressure-resistant container. In this case, the groove is filled with the linear body, a die is inserted, and then, before the material is filled, the linear body is pulled out to open the groove, and the gap is filled with the material through the groove. Thus, the material can be easily filled without using a special plug.

[0016]

1 is a side view of a pressure-resistant container manufactured by a method according to an embodiment, FIG. 2 is a cross-sectional view taken along the line II-II of FIG. 1, and FIGS. FIG. 5 is a sectional view showing a manufacturing method, FIG. 5 is a perspective view of a base, FIGS. 6 and 7 are sectional views showing a method of forming a flange, FIG. 8 is an explanatory view of a filament winding process, and FIG. It is a principal part expanded sectional view.

The pressure-resistant container 1 has a container body 4 composed of an inner shell 2 and an outer shell 3, a base 6 attached to an opening 5 for fluid flow of the container body 4, and an inner peripheral surface of the inner shell 2. A cylindrical part 10 extending from the base 6 and lining the hole 7 of the base 6;
A flange-shaped part 11 and the like are connected to the cylindrical part 10 and line the distal end surface of the base 6.

A nut 8 is screwed onto a male screw engraved on the outer periphery of the base 6 to lock the outer shell 3 from outside.

The inner shell 2 is made of a thermoplastic synthetic resin. For example, as shown in FIGS. 3 and 4, a cylindrical parison 20 made of a thermoplastic synthetic resin is Blow molding is performed by sandwiching the molds 21 and 22.

Reference numerals 25 and 26 in FIG. 4 denote parison cut pieces pinched off by the molds 21 and 22. In this blow molding, as shown in FIG. 4, the tubular portion 10 is formed around the blow pipe 24.

The base 6 shown in FIG. 5 is attached to the upper and lower end portions (end plate portions) of the inner shell 2 thus formed.

The base 6 has a flange portion 31 overlapping the end portion of the inner shell 2 and a pipe portion 32 rising from the flange 31, and a hole 33 of the pipe portion 32 passes through the base 6. I have.

A circular groove 35 is provided in the front end surface of the pipe portion 32 in a counterbore shape, and an annular convex portion 34 is provided on the inner peripheral side of the circular groove 35. The protrusion 34 is recessed from the tip surface of the base 6. A plurality of grooves 36 extend so as to extend from the leading edge of the pipe portion 32 to the outer peripheral edge of the flange portion 31. A linear body 37 is detachably mounted in each groove 36. The linear member 37 is made of a synthetic fluororesin which does not adhere to the synthetic resin forming the outer shell.

The base 6 is attached to the inner shell 2 such that the cylindrical portion 10 is inserted into the hole 33, and the flange 31 is overlapped with the end of the inner shell 2. At this time, the cylindrical portion 1
0 protrudes from the hole 33.

As shown in FIG. 6, the inner shell 2 provided with the base 6 is held between the holders 47 and 48 for forming the flange portions. The holders 47 and 48 are provided with a recess 49 for receiving a second mold 52 described later.

The flanges 11 are provided above the holders 47 and 48 in the drawing.
A press device 50 for forming a sheet is provided. The press device 50 includes a mandrel 55 made of a pipe.
And a first cylindrical mold 5 externally fitted to the mandrel 55.
1, a cylindrical second mold 52 externally fitted to the first mold 51, and a mold holder 53 arranged on the outer periphery of the second mold 52. The second mold 52 is provided with a notched orbiting step 54 that engages with the outer peripheral edge of the upper end of the die 6. A heater 56 is provided on the mandrel 55.
Is provided.

As shown in FIG. 6, the heater 56 and the cylindrical portion 1
The distal end portion of the tubular portion 10 is heated by a heater 57 disposed on the outer periphery of the distal end of the cylindrical portion 10. Next, after the heater 57 is removed, the second mold 52 is protruded as shown in FIG. In this case, the tip of the base 6 enters the orbiting step 54. Note that the inner peripheral surface of the second mold 52 and the outer peripheral wall surface of the orbital groove 35 have the same diameter and form a flush continuous surface.

Next, the first mold 51 is advanced, the tip of the cylindrical portion 10 is pressed, and the thermoplastic synthetic resin forming the tip is inserted into the circumferential groove 35 at the tip of the die 6. To form the flange 11. The convex part 3
4 is recessed from the front end surface of the base 6, the flange 11 covers the projection 34.

Thereafter, the molds 51 and 52 are retracted, and the holders 47 and 48 are opened right and left, whereby the inner shell 2 having the flange 11 is obtained.

As shown in FIG. 8, an outer shell is formed on the outer periphery of the obtained inner shell 2 by a filament winding method or the like.

In FIG. 8, the inner shell 2 is rotatably supported by the inner shell supporting devices 60 and 70 which are disposed relative to each other. The inner shell 2 is rotated by driving a motor (not shown), and the filament 81 impregnated with the thermosetting resin is sent out from the filament supply device 80 and wound around the outer periphery of the inner shell 2. After the helical winding and the tape winding are performed to a predetermined thickness, the rotation of the inner shell 2 is stopped, the block 61 is moved back, and the inner shell 2 is removed.

Next, the inner shell 2 is sent to a heat treatment apparatus to cure the thermosetting synthetic resin adhered to the filaments of the inner shell 2. As a result, the outer shell 3 is formed. As a result of this heat treatment, the inner shell 2 slightly contracts, and a gap 90 is formed between the inner shell 2 and the outer shell 3 as shown in FIG. Therefore, the space 90 is filled with a filling material.

In order to perform this filling, the linear body 37 attached to the groove 36 of the base 6 is pulled out from the groove 36.
Thereby, the groove 36 is opened so as to communicate the atmosphere and the gap 90. Therefore, an appropriate filling nozzle (not shown) is attached to the base 6, and the gap 90 is filled with the filling material through the groove 36. Thereafter, by curing the filler material, the gap between the inner shell 2 and the outer shell 3 is hardened.
A pressure-resistant container filled with is obtained.

As the filling material 91, a hard material such as a hard urethane foam which becomes hard after curing is used.
Further, it is preferable that the filling material has a foaming property, since the filling material is filled to every corner of the void 90.

When filling the filling material, it is preferable to supply a pressurized gas such as pressurized air into the inner shell 2 to apply an inner pressure to the inner shell 2. This prevents the inner shell 2 from shrinking or denting due to the filling pressure.

In the above embodiment, the inside of the inner shell 2 is pressurized in the filling step, but the inside of the inner shell 2 may be pressurized in the filament winding step and the heat treatment step.

When the inside of the inner shell 2 is pressurized also in the filament winding step, there is an effect that the inner shell 2 hardly or hardly contracts in diameter even when a tightening force is applied to the inner shell 2 by the filament winding. Is played.

In the present invention, examples of the resin material constituting the inner shell include polyethylene, cross-linked polyethylene, polypropylene, polyamides, ABS resin, polyethylene terephthalate, polybutylene terephthalate, polyacetal, and polycarbonate. This inner shell synthetic resin may contain reinforcing fibers,
As the reinforcing fibers, the same fibers as in the case of the outer shell described later can be used. Short fibers having a fiber length of about 2 to 10 mm are suitable. The method for forming the inner shell may be a method other than blow, such as rotational molding, compression molding, or injection molding.

The outer shell may be formed by a tape winding method other than the filament winding method.

As the reinforcing fibers of the outer shell, carbon fibers, glass fibers, organic high-modulus fibers (eg, polyamide fibers) and the like can be used.

Examples of the resin for forming the outer shell include thermosetting resins such as epoxy resin, unsaturated polyester resin, vinyl ester resin, and phenol resin.

As the filling material, in addition to the hard urethane type, epoxy type, unsaturated polyester type, vinyl ester type, phenol type and the like can be used. The hardness of the hard urethane or the like has a durometer hardness of 60.
(HDD 60 or more) (JIS K 7215-19)
86).

[0043]

As described above, according to the present invention, there is provided a durable pressure-resistant container in which the space between the outer shell and the inner shell is filled with a hard filler material. ADVANTAGE OF THE INVENTION According to the manufacturing method of this invention, the injection | pouring operation | work of resin into a space | gap is easy and the manufacturing efficiency of a pressure-resistant container is also favorable.

[Brief description of the drawings]

FIG. 1 is a side view of a pressure-resistant container manufactured by a method according to an embodiment.

FIG. 2 is a sectional view taken along the line II-II in FIG.

FIG. 3 is a cross-sectional view illustrating a method for manufacturing an inner shell.

FIG. 4 is a cross-sectional view illustrating a method for manufacturing an inner shell.

FIG. 5 is a perspective view of a base.

FIG. 6 is a cross-sectional view illustrating a method of forming a flange.

FIG. 7 is a cross-sectional view showing a method of forming a flange.

FIG. 8 is a side view showing a filament winding step.

FIG. 9 is an enlarged sectional view of a main part of the pressure-resistant container being manufactured.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pressure-resistant container 2 Inner shell 3 Outer shell 6 Cap 10 Cylindrical part 11 Flange part 20 Parison 31 Flange part 35 Orbital groove 47, 48 Inner shell holder 50 Press device 51 First mold 52 Second mold 53 Mold holder 54 Step 55 Mandrel 60, 70 Inner shell support device 61, 71 Support block 80 Filament supply device 81 Filament 90 Void

Claims (5)

[Claims] 1. A pressure-resistant container having an inner shell made of a synthetic resin, an outer shell covering the inner shell, and a packing layer filled between the inner shell and the outer shell, wherein the filling layer is a hard body. A pressure-resistant container characterized by comprising: 2. The pressure-resistant container according to claim 1, wherein the filling layer is made of a rigid foam. 3. A step of molding the inner shell with a synthetic resin, a step of molding an outer shell covering the outer surface of the inner shell, and a step of filling a gap between the inner shell and the outer shell with a filling material. A method for manufacturing a pressure-resistant container, comprising: filling a material that becomes hard after curing as the filling material. 4. The method for manufacturing a pressure-resistant container according to claim 3, wherein the inside of the inner shell is pressurized by supplying a pressurized gas into the inner shell when the filling material is filled. . 5. The pressure-resistant container according to claim 3, wherein a base is inserted into an end of the pressure-resistant container, and a groove for guiding a filling material is provided on an outer peripheral surface of the base. Inserting a base which is filled with a body, pulling out the linear body prior to filling, opening a groove so as to communicate with the gap, and filling the gap with a filling material through the groove. Pressure vessel manufacturing method.