JP2000266288A - Pressure vessel and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a reinforcing material from being deviated and prevent an inner shell from being deformed by providing a lock part locking the base end of a mouth ring relative to the inner shell and covering the inner shell, the mouth ring base end part, and the lock part with an outer shell. SOLUTION: A lock part 9 locking a mouth ring 6 to an inner shell 2 is provided. The tip of the lock part 9 is closely fitted to the flange edge of the mouth ring 6 and the lock part 9 is fused to the inner shell. This constitution fixes the flange edge of the mouth ring 6 by the lock part 9 so that the eccentricity and deformation of the inner shell 2 can be prevented in a filament winding process. In the hardening process of the FRP reinforcing layer, this constitution can also prevent the deformation of the pressure vessel 1. Moreover, this constitution can prevent the eccentricity and the deformation of the inner shell 2 through the whole process so as to improve the dimensional accuracy of the pressure vessel 1.

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 method of manufacturing a pressure-resistant container for filling various liquefied gases such as PG (liquefied petroleum gas) and other various pressurized substances.

[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, an inner shell is formed of a synthetic resin by a rotational molding method, a blow 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. Thereafter, a reinforcing fiber such as carbon having an epoxy resin or the like adhered to the outer periphery of the inner shell is helically wound and hoop-wound to form an FRP reinforcing layer by winding.
C., and the resin of the FRP reinforcing layer is cured by heating to form an outer shell.

[0004]

When the FRP reinforcing layer is wound around the inner shell by helical winding or hoop winding, the inner shell is eccentric due to the winding force and the tightening force, and the reinforcing fibers are arranged. May not be performed as designed or the inner shell may be deformed. In addition, when receiving heat in a thermostat in the curing step of the FRP reinforcing layer, the pressure-resistant container sometimes deformed.

[0005] It is an object of the present invention to provide a pressure-resistant container in which such displacement of the reinforcing fibers and deformation of the inner shell and the like are prevented, and a method for producing the same.

[0006]

According to the present invention, there is provided a pressure-resistant container comprising: an inner shell made of a synthetic resin; a base arranged at the center of at least one end plate of the inner shell; and a base outside the base end of the base. In a pressure-resistant container having a peripheral portion and an outer shell made of FRP covering an outer surface of the inner shell, a locking portion for locking a base end of the base to the inner shell is provided, and an inner shell and a base end of the base are provided. The part and the locking part are covered with the outer shell.

According to the method for manufacturing a pressure-resistant container of the present invention, a step of molding an inner shell of a synthetic resin, a step of arranging a base at the center of at least one end plate portion of the inner shell, and a step of forming a base end of the base. A method for producing a pressure-resistant container, comprising: a winding step of winding and forming an FRP reinforcing layer so as to cover an outer surface of the inner shell; and a heat treatment step of heating and curing an impregnated resin of the FRP reinforcing layer to form an outer shell. After arranging the base, the outer peripheral edge of the base end of the base is locked to the inner shell by a locking portion, and then a winding step is performed.

As described above, by locking the outer peripheral edge of the base end of the base to the inner shell prior to the formation of the outer shell, eccentricity and deformation of the inner shell and deformation of the pressure-resistant container are prevented. The dimensional accuracy of the pressure vessel is improved.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a side view of a pressure vessel according to an embodiment, FIG. 2 is a sectional view taken along the line II-II of FIG.
4 is a cross-sectional view showing a method of manufacturing the inner shell, FIG. 5 is a perspective view of a base, FIGS. 6 to 9 are explanatory views of a base mounting process, and FIGS.
Is a cross-sectional view showing a method of forming a flange, and FIG. 12 is an explanatory view of a filament winding step.

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 the base 6 connected to the inner shell 2. A cylindrical portion 10 extending from the inner peripheral surface of the inner shell 2 and lining the hole 7 of the base 6, and a leading end of the base 6 connected to the cylindrical portion 10; It is composed of a flange-like portion 11 lining the surface.

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 tubular parison 20 made of a thermoplastic synthetic resin 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 dies 21 and 22. In this blow molding, as shown in FIG. 4, the tubular portion 10 is formed around the blow pipe 24.

A 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 31 overlapping the end of the inner shell 2 and a pipe 32 rising from the flange 31, and a hole 33 of the pipe 32 penetrates the base 6. ing. A flat edge 36 is provided around the outer peripheral edge of the flange 31 by forming a step in the circumferential direction.

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. This base 6 has holes 3
3, the cylindrical portion 10 is inserted into the inner shell 2, and the flange portion 31 is inserted into the inner shell 2.
Is attached to the inner shell 2 so as to overlap the end portion of the inner shell. At this time, the cylindrical portion 10 protrudes from the hole 33.

As described above, the inner shell 2 having the base 6 is held between the holders 67 and 68 for forming the locking portions as shown in FIG. The holders 67 and 68 are provided with a concave portion 69 for receiving a heater 76 and an annular jig 61 described later.

A press device 60 for forming the locking portion 9 is disposed above the holders 67 and 68 in FIG.
The press device 60 includes a mandrel 65 made of a pipe.
And a mold holder 62 arranged on the outer periphery of the mandrel 65, and a mold 63 externally fitted to the mold holder 62. An annular jig 61 is held at the tip of the mold 63. Is done.

As shown in FIG. 7, the heater 76 is inserted into the concave portion 69 and brought into contact with the edge 36, and the flange 76 of the base 6 is heated by the heater 76. Next, after the heater 76 is removed, the mold 63 is protruded as shown in FIG. 8, and the annular jig 61 and the locking portion 9 held at the tip of the mold 63 are attached to the flange edge 36 of the base 6. Engage. At the same time, gas is sent from the tip of the mandrel 65 to pressurize the inner shell 2 from the inside. As a result, the tip of the locking portion 9 comes into close contact with the flange edge portion 36 of the base 6, and the locking portion 9 is
Fused.

The engaging portion 9 and the inner shell 2 are made of a material having good fusion property, usually the same material, but one or both of the fused portion of the engaging portion 9 and the inner shell 2 are bonded. It may be made of a resin having a property.

As the adhesive resin, an unsaturated carboxylic acid-modified ethylene resin is preferable. The unsaturated carboxylic acid-modified ethylene-based resin refers to a resin modified by grafting an unsaturated carboxylic acid or a derivative thereof to polyethylene, an ethylene-α-olefin copolymer, or the like. This adhesive resin has a graft amount (measurement method: measured by an infrared spectrophotometer) of 0.01 to 10% by weight and a density (measurement method: JI
0.88 to 0.945 g / c according to SK7112)
m is ^3, MFR (measuring method: JIS K7210, conforming to Table 1 Condition 4) is of 0.05 to 50 g / 10min.

If the graft amount is less than 0.01% by weight, good adhesion is not exhibited, and if the graft amount exceeds 10% by weight, it is difficult to produce, and the adhesion is also poor, which is not preferable. Particularly preferred amount of grafting is in the range of 0.1 to 5% by weight. Less density 0.88 g / cm ^3, or exceeds 0.945 g / cm ^3, both inferior adhesive strength is undesirable. Further, the MFR is less than 0.05 g / 10 min or 50
If it exceeds g / 10 min, it is difficult to form an adhesive resin layer having a desired thickness in the disc-shaped buried portion, which is not preferable.

The unsaturated carboxylic acid-modified ethylene resin having the above properties can be produced by a conventionally known production method. For example, (1) an olefin-based polymer (including a mixture of two or more types in addition to one type) and a graft monomer (an unsaturated carboxylic acid or a derivative thereof)
Are mixed in advance with a radical polymerization initiator to form a mixture, and this mixture is melted with an extruder to carry out graft copolymerization; (2) an olefin-based polymer (1
(Including a mixture of two or more kinds) in a solvent, and adding a radical polymerization initiator, a graft monomer and the like to carry out graft copolymerization.

Thereafter, the mold 63 is retracted and the holder 6
By opening 7, 68 right and left, the inner shell 2 in which the flange edge 36 of the base 6 is locked via the locking portion 9 as shown in FIG. 9 is obtained.

As shown in FIG. 10, the inner shell 2 having the base 6 fixed via the locking portion 9 and the annular jig 61 fitted to the base 6 is used to form a flange-shaped portion. Holders 47, 4
Hold at 8. The holders 47 and 48 are provided with a recess 49 for receiving a second mold 52 described later.

A pressing device 50 for forming the flange 11 is disposed above the holders 47 and 48 in FIG. The press device 50 includes a mandrel 55 composed of a pipe, a first cylindrical mold 51 externally fitted to the mandrel 55, and a second cylindrical mold externally fitted to the first mold 51. 52, 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. Further, the mandrel 55 is provided with a heater 56.

As shown in FIG. 10, the distal end portion of the cylindrical portion 10 is heated by the heater 56 and the heater 57 disposed on the outer periphery of the distal end of the cylindrical portion 10. Next, after the heater 57 is withdrawn, the second mold 52 is projected as shown in FIG.
The upper end of the base 6 is engaged. 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, the holders 47 and 48 are opened to the left and right, and the annular jig 61 is detached, whereby the inner shell 2 having the flange 11 is obtained.

As shown in FIG. 12, an outer shell is formed on the outer periphery of the obtained inner shell 2 by a filament winding method or the like to manufacture a pressure-resistant container.

As shown in FIG. 12, the inner shell 2 is rotatably supported by the inner shell supporting devices 160 and 170 disposed relative to each other. The supporting device 160 is capable of moving forward and backward in the left-right direction of FIG. 8. When the inner shell 2 is attached and detached, the supporting device 160 retreats rightward in FIG. 8 to hold (chuck) the inner shell 2. At times, the support device 160 advances to the left in FIG.

From the compressor 168 to the pressure hose 167
Air is supplied to the inner shell 2 by a predetermined pressure, and the inner shell 2 is rotated by driving a motor (not shown) while the inner shell 2 is pressurized with air from the inside. The filament 181 impregnated with the curable resin is sent out 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 motor and the compressor 168 are stopped, and the inner shell 2 is removed.

Next, a blind cap (not shown) is mounted on one base 6 of the inner shell 2 and an air feed hose (not shown) is mounted on the other base 6 and then supplied to a heat treatment apparatus. Inner shell 2 via air feed pipe
Heat is applied while a predetermined air pressure is applied to the inside to cure the thermosetting synthetic resin attached to the filament of the inner shell 2.

In this embodiment, since the flange edge 36 of the base 6 is fixed to the inner shell 2 by the locking portion 9, eccentricity and deformation of the inner shell 2 are not generated in the filament winding process. Is prevented. Also, F
In the curing step of the RP reinforcing layer, deformation of the container is prevented. The eccentricity and deformation of the inner shell are prevented throughout the entire process, thereby improving the dimensional accuracy of the pressure-resistant container.

In the present embodiment, since the inner shell 2 is subjected to the thermosetting treatment while being pressed from the inside, the inner shell 2 does not shrink in the thermosetting treatment step, and A pressure vessel in which the outer shell 3 is in close contact is manufactured.

Although not particularly limited to the present invention, the inside of the inner shell 2 is preferably 0.5 to 3 atm, particularly 0.8 to 3 atm in the filament winding or thermosetting treatment step.
It is preferable to keep the pressure at 2.5 atm, especially about 1.0 to 2 atm.

In the above embodiment, the inner shell 2 is formed from the filament winding step to the heat curing step.
Although the inside is pressurized, the inside of the inner shell 2 may be pressurized only in the heat treatment step.

When the inside of the inner shell 2 is pressurized also in the filament winding step, the inner shell 2 is not or hardly reduced in diameter even when a tightening force is applied to the inner shell 2 by the filament winding. The effect is achieved. Further, in the above embodiment, the inside of the inner shell 2 is pressurized by supplying the pressurized air into the inner shell 2, but in the thermosetting treatment step, both the bases 6 are blinded. After attaching the cap and sealing the inside, heat it,
The inside of the inner shell 2 may be pressurized by thermally expanding the internal air.

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 (for example, 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.

[0043]

As described above, according to the present invention, a good pressure-resistant container without deformation and eccentricity of the container can be manufactured. According to this manufacturing method, it is not necessary to consider the deformation problem of the inner shell when manufacturing the FRP reinforcing layer, so that the manufacturing efficiency of the pressure vessel is also good.

[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 showing a locking method of the locking portion.

FIG. 7 is a cross-sectional view illustrating a locking method of the locking portion.

FIG. 8 is a cross-sectional view showing a locking method of the locking portion.

FIG. 9 is a cross-sectional view of an inner shell provided with a locking portion and an annular jig.

FIG. 10 is a cross-sectional view showing a method of forming a flange.

FIG. 11 is a cross-sectional view showing a method of forming a flange.

FIG. 12 is a side view showing a filament winding step.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pressure-resistant container 2 Inner shell 3 Outer shell 6 Cap 9 Locking part 10 Cylindrical part 11 Flange part 20 Parison 31 Flange part 35 Circular groove 36 Flange edge 47, 48 Inner shell holder 50 Pressing device 51 First metal Mold 52 second mold 53 mold holder 54 step 55 mandrel 60 press device 61 annular jig 62 mold holder 63 mold 65 mandrel 67, 68 holder 69 recess 76 heater 160, 170 inner shell support device 180 filament Feeder 181 Filament

 ──────────────────────────────────────────────────の Continued on front page F term (reference) 3E072 AA10 BA04 CA01 4F205 AA03J AA20J AA39 AD03 AD05 AD16 AG03 AH55 HA02 HA08 HA14 HA17 HA23 HA25 HA32 HA33 HA34 HA36 HA37 HA40 HA44 HA46 HB01 HB11 HC14 HC16 HC17 HF01 HF05 HF05 HF05 HF05 HF05 HF05 HF05 HK05 HK07 HK14 HK17 HL02 HT03 HT08 HT22 HT27

Claims (2)

[Claims] 1. An inner shell made of synthetic resin, a base arranged at the center of at least one end plate of the inner shell, an outer shell made of FRP covering a base end of the base and an outer surface of the inner shell. A pressure-resistant container having: a locking portion for locking an outer peripheral edge of a base end portion of the base to the inner shell; and an inner shell, a base end portion of the base, and the locking portion on the outer shell. A pressure-resistant container characterized by being covered. 2. A step of molding an inner shell of a synthetic resin, a step of arranging a base at the center of at least one end plate of the inner shell, and a step of covering a base end of the base and an outer surface of the inner shell. In a method for manufacturing a pressure-resistant container having a winding step of winding and forming an FRP reinforcing layer on a FRP reinforcing layer, and a heat treatment step of heating and curing the impregnated resin of the FRP reinforcing layer to form an outer shell, after disposing the base, A method for manufacturing a pressure-resistant container, wherein an outer peripheral edge portion of a base end portion of a base is locked to an inner shell by a locking portion, and then a winding step is performed.