WO2019107967A1

WO2019107967A1 - Gas container

Info

Publication number: WO2019107967A1
Application number: PCT/KR2018/014953
Authority: WO
Inventors: 이교민; 송민수; 황연희
Original assignee: 롯데케미칼 주식회사
Priority date: 2017-11-30
Filing date: 2018-11-29
Publication date: 2019-06-06
Also published as: KR20190064207A; KR102248953B1

Abstract

Provided is a gas container comprising: a liner containing gas and molded with resin; an ethylene vinyl alcohol film formed on the outer surface of the liner; and a composite material layer formed on the outer surface of the ethylene vinyl alcohol film.

Description

Gas container

The present invention relates to a gas container. More specifically, the present invention can increase the oxygen shielding effect and heat resistance, increase the tightening strength with the pump and the valve, and secure the stable structure in which only the gas leakage in the cylinder occurs due to the tearing of the cylinder before rupture when the pressure is applied. The present invention relates to a gas container which can be used as a gas container.

A gas container is a pressure vessel made by winding a metal liner surface completely covered with a fiber impregnated with an epoxy resin or the like, for example, carbon fiber. In the process of evolving catastrophes, firefighters can get the necessary oxygen through the gas container.

The existing gas container is a metallic liner using TYPE3 (aluminum liner for inner liner and composite layer for outer liner) using aluminum liner with oxygen permeability close to zero. Composite pressure vessel is used. However, the container is oxidized by the oxidation of the coating layer on the surface of aluminum for a long time, and the problem of heavy metal poisoning upon inhalation of the human body is emerging. In addition, the gas container has a characteristic that the user must travel for a long period of time when a fire occurs, resulting in a decrease in the physical strength of the user and a reduction in the moving speed for a long period of use.

Recently, TYPE4 composite containers are being developed, which are made of nonmetallic liner and composite fiber, replacing metallic liner. The TYPE4 composite container uses a polyethylene terephthalate liner as a non-metallic liner instead of the metal liner of the TYPE3 composite container. However, unlike an aluminum liner, the polyethylene terephthalate liner has a high oxygen permeability and thus has a low oxygen shielding effect, and has a low glass transition temperature and low heat resistance. Therefore, development of a gas container capable of solving such problems is urgent.

The background art of the present invention is disclosed in Korean Patent No. 10-0469636.

An object of the present invention is to provide a gas container capable of increasing the oxygen shielding effect and heat resistance by attaching an ethylene vinyl alcohol film to the outer surface of a liner made of a thermoplastic resin film.

Another object of the present invention is to provide a gas container which can include a liner joint bonded by thermosetting in a boss portion to increase the fastening strength with a pump or a valve.

Another object of the present invention is to provide a gas container with a stable structure in which, when pressure is applied, a portion of the cylinder before rupture tears and only gas leakage occurs in the cylinder.

1. One aspect of the present invention relates to a gas container. In one embodiment, the gas container comprises a liner that is gas-received and molded into a resin; An ethylene vinyl alcohol film formed on an outer surface of the liner; And a composite layer formed on the outer surface of the ethylene vinyl alcohol film.

2. In one embodiment, the ethylene vinyl alcohol film may be formed on the outer surface of the liner in a taping manner.

3. In the above-mentioned 1-2 embodiments, the resin may include at least one of polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, and polybutylene naphthalate.

4. In the above-mentioned 1-3 embodiments, the pressure vessel may further include a boss portion, and the boss portion may include a liner boss portion formed by thermosetting.

5. In the 1-4 embodiments, the boss portion may further include a metal boss portion surrounding the liner boss portion.

6. In embodiments 1-5 above, the metal boss may be connected to the liner.

The present invention provides a gas container capable of enhancing the oxygen shielding effect and heat resistance by attaching an ethylene vinyl alcohol film to the outer surface of a liner made of a thermoplastic resin film.

The present invention provides a gas container capable of increasing the fastening strength with a pump or a valve by incorporating a liner joint bonded by thermosetting into a boss portion.

The present invention provides a gas container with a stable structure in which, when pressure is applied, only a portion of the cylinder before rupture tears and only gas leakage occurs in the cylinder.

1 is a cross-sectional view of a gas container according to one embodiment of the present invention.

One embodiment of the present invention will be described in more detail with reference to the accompanying drawings. However, the techniques disclosed in this application are not limited to the embodiments described herein but may be embodied in other forms. It should be understood, however, that the embodiments disclosed herein are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

The inventor of the present invention has found that when the liner in which the compressed air is accommodated is made of a resin material, particularly a polyethylene terephthalate film, the polyethylene terephthalate film has high oxygen permeability so that oxygen can easily permeate from the outside, , The glass transition temperature is low and the heat resistance is low. Thus, it has been confirmed that the oxygen shielding effect and the heat resistance can be enhanced by attaching the ethylene vinyl alcohol film to the outer surface of the liner made of resin in which the air is contained, and the present invention has been accomplished.

Hereinafter, the gas container of the present invention will be described with reference to Fig. 1 is a cross-sectional view of a gas container according to one embodiment of the present invention.

Referring to FIG. 1, the gas container 100 may include a composite pressure vessel in which a liner 10, an ethylene-vinyl alcohol film 20, and a composite layer 30 are sequentially stacked. The composite pressure vessel comprises a cylinder 110 for receiving gas, a dome 120 connected to one side of the cylinder 110, and a boss 130 connected to the other side of the cylinder 110.

The liner 10 is made of resin and can form the cylinder 110 to receive air. Since the liner 10 is made of resin, it can solve problems such as generation of foreign matter such as rust due to corrosion of metal liners such as aluminum and heavy metal poisoning. In addition, the resin may be selected from those having low reactivity with gas and good bonding property. For example, the resin may be a polyester resin such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, or polybutylene naphthalate.

The liner 10 is made of resin, and particularly polyethylene terephthalate has high oxygen permeability and low glass transition temperature. Therefore, by forming an ethylene vinyl alcohol (EVOH) film on the outer surface of the liner, the oxygen permeability can be compensated to increase the oxygen shielding effect and the glass transition temperature to increase the heat resistance.

The liner 10 can be manufactured by a fusion bonding method in which each of the portions constituting the liner, that is, the boss portion, the dome portion, and the cylinder portion is manufactured and then bonded at respective interfaces by ultrasonic welding or heat welding. In the case of the fusion bonding method, an interface due to fusion bonding is formed between the boss portion, the dome portion and the cylinder portion. If there is a problem with one or more of the boss, dome, or cylinder, you can remove the problem and replace it with a new one.

Alternatively, the liner can be made by blow molding. The blow molding method is a method in which a liner base is inserted into a blow mold and air is blown into the liner base to expand the liner base into a liner shape to be made. The liner 10 functions as a mandrel at the time of forming the composite layer. When the liner is used as a mandrel to form a composite layer on the liner, the composite layer is wound around the liner as a base material, so that the formability and strength of the composite layer can be improved.

The ethylene vinyl alcohol film 20 is formed between the liner 10 and the composite material layer 30 and can enhance the oxygen shielding effect and heat resistance as described above. Referring to I-II in Fig. 1, the composite pressure vessel is composed of a three-layer structure of the liner 10, the ethylene vinyl alcohol film 20, and the composite layer 30 from the inside. In addition, the ethylene vinyl alcohol film is installed in a pressure vessel to generate a maximum stress in a body region, which is the most ideal rupture mode of the pressure vessel, so that the gas is leaked only when the portion is torn before rupture, .

The ethylene vinyl alcohol film (20) is a copolymer of ethylene and vinyl alcohol, and can be a conventional kind known to those skilled in the art.

In one embodiment, the copolymer of ethylene vinyl alcohol can be made from a copolymer of ethylene and vinyl alcohol. In another embodiment, the copolymer of ethylene vinyl alcohol may be prepared by preparing a copolymer of ethylene and vinyl acetate followed by hydrolysis. Copolymer preparation and hydrolysis are by conventional methods known to those skilled in the art.

The ethylene vinyl alcohol film 20 may be applied to the outer surface of the liner 10 in a taping manner. When taping method is applied, oxygen shielding and heat resistance can be improved.

The composite layer 30 is laminated on the outer surface of the ethylene vinyl alcohol film 20 and can enclose the entire pressure vessel to withstand the pressure of the air rechargeable battery in the pressure vessel.

The composite layer 30 may comprise a layer on which a fibrous member comprising fibers is wound. The fibrous member may be dry-wound. However, by impregnating the fiber member with a resin or the like and wet-winding it, it is possible to better sustain the internal pressure when filling the pressure vessel. The resin may include, but is not limited to, an epoxy resin, a vinyl ester, and the like. The fibers may include, but are not limited to, glass fibers, metal fibers, carbon fibers, aramid fibers, pitch fibers, polyester fibers, basalt fibers and the like.

The dome portion 120 is connected to the cylinder portion 110 and closes one side of the cylinder portion 110.

The dome portion 120, like the cylinder portion, can be composed of a liner, an ethylene vinyl alcohol film formed on the outer surface of the liner, and a composite material layer formed on the outer surface of the ethylene vinyl alcohol film.

The dome 120 may have a knob. The knobs can be made to wind the fibers evenly over the liner and the ethylene vinyl alcohol film by engaging the fibers when winding the glass or carbon fibers when forming the composite layer on the outer surface after molding the liner and the ethylene vinyl alcohol film.

The boss unit 130 is connected to the cylinder unit 110 and closes the other side of the cylinder unit 110.

The boss portion 130 is a portion that connects the cylinder portion 110 and the external gas inlet, and serves as a passage for the gas. The boss unit 130 includes a metal boss unit 50 in which a pump or a valve is mounted for injecting gas into the cylinder unit 110 and a liner boss unit 60 for connecting the boss unit to the liner.

The liner boss portion 60 is joined to the cylinder portion 110, particularly the liner, and serves as a passage for gas injection from the outside.

The liner boss portion 60 may be formed of a thermosetting resin. By forming the liner boss portion 60 with a thermosetting resin, the strength can be reinforced when the liner boss portion 60 is connected to the gas injection tube from the outside, thereby preventing the gas from leaking. The thermosetting resin is not particularly limited, but an epoxy resin, a phenol resin, a polyurethane resin, and an unsaturated polyester resin can be used.

The metal boss portion (50) is tightened with a pump or a valve for gas injection. The metal boss portion 50 is made of a metal material so that a valve or a pump for controlling the flow rate of the gas must be fastened by bolt or welding, and the deformation resistance should be high.

The metal boss portion 50 is formed so as to surround the liner boss portion so as to reinforce the structure of the liner boss portion and secure the thread shape when gas is injected from the outside. The metal boss portion 50 may be formed of a common metal such as aluminum, but is not limited thereto.

The metal boss portion 50 is connected to the liner to reinforce the strength of the liner and can act as a fastener when injecting gas from the outside.

Hereinafter, the configuration and operation of the present invention will be described in more detail with reference to preferred embodiments of the present invention. It is to be understood, however, that the same is by way of illustration and example only and is not to be construed in a limiting sense.

실시예Example

As shown in FIG. 1, the liner 10 is formed of a resin and is gas-containing. An ethylene vinyl alcohol film 20 formed on the outer surface of the liner 10; And a composite material layer (30) formed on the outer surface of the ethylene vinyl alcohol film (20). The test pressure was applied to the composite pressure vessel, and the distribution of compressive residual stress was observed. As a result, the maximum stress was observed in the cylinder portion 110 of the composite pressure vessel. As a result, it was confirmed that the gas container tore the cylinder portion 110 before the rupture when the gas container was pressurized, resulting in only a leakage of the gas from the cylinder portion 110.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

A liner that is gas-containing and molded into a resin;

An ethylene vinyl alcohol film formed on an outer surface of the liner; And

And a composite layer formed on an outer surface of the ethylene vinyl alcohol film.
The method according to claim 1,

Wherein the ethylene vinyl alcohol film is formed on the outer surface of the liner in a taping manner.
The method according to claim 1,

Wherein the resin comprises at least one of polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, and polybutylene naphthalate.
The method according to claim 1,

The gas container further comprising a boss portion,

Wherein the boss portion comprises a liner boss portion formed by thermosetting.
5. The method of claim 4,

Wherein the boss portion further comprises a metal boss portion surrounding the liner boss portion.
6. The method of claim 5,

Wherein the metal boss portion is connected to the liner.