阅读说明：本技术 复合气瓶及其成型方法 (Composite gas cylinder and forming method thereof ) 是由 于海泉 张强 于 2019-04-09 设计创作，主要内容包括：本发明提供了一种复合气瓶,包括塑料内胆、嵌设于塑料内胆端部的金属瓶头及缠绕于塑料内胆外壁的缠绕层。塑料内胆包括内胆内层和成型于内胆内层外壁的加强层,内胆内层的端部与金属瓶头一体成型。内胆内层的材质为热塑性树脂,加强层的材质为纤维增强热塑性树脂；缠绕层的材质为纤维增强环氧树脂。本发明的复合气瓶通过增大加强层与内胆内层之间的连接强度,增加加强层与缠绕层之间的粘接强度,而增强了缠绕层与塑料内胆之间的粘接结合力,从而增加了金属瓶头与塑料内胆衔接处的连接强度,保证了金属瓶头与塑料内胆的位移同步,从而提高了复合气瓶的质量。(The invention provides a composite gas cylinder which comprises a plastic inner container, a metal cylinder head embedded at the end part of the plastic inner container and a winding layer wound on the outer wall of the plastic inner container. The plastic inner container comprises an inner container layer and a reinforcing layer formed on the outer wall of the inner container layer, and the end part of the inner container layer and the metal bottle head are integrally formed. The inner layer of the inner container is made of thermoplastic resin, and the reinforcing layer is made of fiber reinforced thermoplastic resin; the winding layer is made of fiber reinforced epoxy resin. According to the composite gas cylinder, the bonding strength between the reinforcing layer and the inner layer of the liner is increased, the bonding strength between the reinforcing layer and the winding layer is increased, and the bonding force between the winding layer and the plastic liner is enhanced, so that the bonding strength of the joint of the metal cylinder head and the plastic liner is increased, the displacement synchronization of the metal cylinder head and the plastic liner is ensured, and the quality of the composite gas cylinder is improved.)

1. A composite gas cylinder comprises a plastic inner container, a metal cylinder head embedded at the end part of the plastic inner container and a winding layer wound on the outer wall of the plastic inner container,

the plastic inner container comprises an inner container layer and a reinforcing layer formed on the outer wall of the inner container layer, and the end part of the inner container layer is integrally formed with the metal bottle head; the inner layer of the inner container is made of thermoplastic resin, and the reinforcing layer is made of fiber reinforced thermoplastic resin;

the material of winding layer is fiber reinforcement epoxy, winding layer with the enhancement layer is connected fixedly.

2. The composite gas cylinder according to claim 1, characterized in that the outer wall of the reinforcing layer is coated with epoxy resin, and the epoxy resin is coupled with the fibers of the reinforcing layer and bonded with the winding layer, so that the winding layer is fixedly connected with the reinforcing layer.

3. The composite gas cylinder according to claim 1, characterized in that the fibers of the reinforcement layer are coupled with the epoxy resin of the wrapping layer, so that the wrapping layer is fixedly connected with the reinforcement layer.

4. A method for forming a composite gas cylinder is characterized by comprising the following steps:

forming an inner liner layer by using thermoplastic resin as a raw material, and integrally forming a metal bottle head and the inner liner layer in the inner liner layer forming process;

heating and softening the outer wall of the inner layer of the inner container;

wrapping the fiber reinforced thermoplastic resin prepreg subjected to heating softening on the outer wall of the inner layer of the inner container subjected to heating softening, and molding to obtain a reinforcing layer;

and winding fiber reinforced epoxy resin on the outer wall of the reinforcing layer to form a winding layer.

5. The method for forming a composite gas cylinder according to claim 4, wherein the step of winding the fiber reinforced epoxy resin around the outer wall of the reinforcing layer to form the winding layer specifically comprises:

processing the outer surface of the reinforcing layer, and removing the thermoplastic resin on the outer surface of the reinforcing layer to expose the fibers on the outer surface of the reinforcing layer;

winding the fiber reinforced epoxy resin around the outer surface of the reinforcement layer such that the epoxy resin of the wound layer is coupled with the fibers of the outer surface of the reinforcement layer.

6. The method for forming a composite gas cylinder according to claim 4, wherein the step of winding the fiber reinforced epoxy resin around the outer wall of the reinforcing layer to form the winding layer specifically comprises:

processing the outer surface of the reinforcing layer, and removing the thermoplastic resin on the outer surface of the reinforcing layer to expose the fibers on the outer surface of the reinforcing layer;

coating epoxy resin on the fibers exposed outside the outer surface of the reinforcing layer so that the epoxy resin is coupled with the fibers of the reinforcing layer;

and winding the fiber reinforced epoxy resin on the outer surface of the reinforcing layer, so that the epoxy resin is bonded with the winding layer.

7. The method of forming a composite gas cylinder according to claim 6, characterized in that the epoxy resin is cured simultaneously with the winding layer.

8. The method for forming a composite gas cylinder according to any one of claims 4 to 7, wherein the step of winding the fiber reinforced epoxy resin around the outer wall of the reinforcing layer to form a winding layer specifically comprises:

the fiber reinforced epoxy resin is wound on the cylinder body of the reinforcing layer in an annular winding mode, and then wound on the cylinder body and the seal head of the reinforcing layer in a spiral winding mode.

9. The forming method of the composite gas cylinder according to claim 4, characterized in that the outer wall of the inner layer of the liner is heated and softened by infrared, laser or high-temperature hot gas spraying;

the fiber reinforced thermoplastic resin prepreg is heated and softened by infrared, laser or high-temperature hot air blowing.

10. The method for molding the composite gas cylinder according to claim 4, wherein the fiber in the fiber-reinforced thermoplastic resin prepreg is a continuous fiber, and the fiber-reinforced thermoplastic resin prepreg is wound around the outer wall of the inner liner layer in a spiral winding manner.

Technical Field

The invention relates to the technical field of pressure containers, in particular to a composite gas cylinder and a forming method thereof.

Background

In order to keep pace with the ever-increasing requirements for environmental protection, domestic new energy and clean energy technologies have also made great progress. In the field of energy storage and transportation equipment, attention is increasingly paid to a fully-wound composite gas cylinder with a high volume-weight ratio and a corrosion-resistant IV-type plastic liner. Consumers also enjoy such products.

The current plastic liner fully-wound composite material type gas cylinder mostly adopts a three-layer structure comprising a liner layer, a winding layer and an outer protective layer, wherein a bottle opening of the plastic liner fully-wound composite material type gas cylinder is a metal bottle head, the liner layer is made of plastic, the metal bottle head and a seal head of the liner layer are molded through an injection molding process, and then the seal head of the liner and a cylinder body part of the liner are welded together. The metal bottle head and the inner container can also be integrally formed by a rotational molding process. No matter the composite gas cylinder is formed by a rotational molding process or an injection molding process, the inner container layer of the formed composite gas cylinder deforms greatly under the action of high pressure, so that the metal cylinder head and the inner container layer are deformed asynchronously easily, and then the interface of the metal cylinder head and the inner container layer is peeled off, so that the gas cylinder leaks.

Disclosure of Invention

The invention aims to provide a composite gas cylinder with high quality to solve the problems in the prior art.

In order to solve the technical problem, the invention provides a composite gas cylinder which comprises a plastic inner container, a metal cylinder head embedded at the end part of the plastic inner container and a winding layer wound on the outer wall of the plastic inner container, wherein the plastic inner container comprises an inner container layer and a reinforcing layer formed on the outer wall of the inner container layer, and the end part of the inner container layer and the metal cylinder head are integrally formed; the inner layer of the inner container is made of thermoplastic resin, and the reinforcing layer is made of fiber reinforced thermoplastic resin; the material of winding layer is fiber reinforcement epoxy, winding layer with the enhancement layer is connected fixedly.

In one embodiment, the outer wall of the reinforcing layer is coated with epoxy resin, and the epoxy resin is coupled with the fibers of the reinforcing layer and bonded with the winding layer, so that the winding layer is fixedly connected with the reinforcing layer.

In one embodiment, the fibers of the reinforcement layer are coupled to the epoxy resin of the wrapping layer, thereby securing the wrapping layer to the reinforcement layer.

The invention also provides a forming method of the composite gas cylinder, which comprises the following steps:

forming an inner liner layer by using thermoplastic resin as a raw material, and integrally forming a metal bottle head and the inner liner layer in the inner liner layer forming process;

heating and softening the outer wall of the inner layer of the inner container;

wrapping the fiber reinforced thermoplastic resin prepreg subjected to heating softening on the outer wall of the inner layer of the inner container subjected to heating softening, and molding to obtain a reinforcing layer;

and winding fiber reinforced epoxy resin on the outer wall of the reinforcing layer to form a winding layer.

In one embodiment, the step of winding the fiber reinforced epoxy resin around the outer wall of the reinforcing layer to form the wound layer specifically includes:

processing the outer surface of the reinforcing layer, and removing the thermoplastic resin on the outer surface of the reinforcing layer to expose the fibers on the outer surface of the reinforcing layer;

winding the fiber reinforced epoxy resin around the outer surface of the reinforcement layer such that the epoxy resin of the wound layer is coupled with the fibers of the outer surface of the reinforcement layer.

In one embodiment, the step of winding the fiber reinforced epoxy resin around the outer wall of the reinforcing layer to form the wound layer specifically includes:

processing the outer surface of the reinforcing layer, and removing the thermoplastic resin on the outer surface of the reinforcing layer to expose the fibers on the outer surface of the reinforcing layer;

coating epoxy resin on the fibers exposed outside the outer surface of the reinforcing layer so that the epoxy resin is coupled with the fibers of the reinforcing layer;

and winding the fiber reinforced epoxy resin on the outer surface of the reinforcing layer, so that the epoxy resin is bonded with the winding layer.

In one embodiment, the epoxy resin is cured simultaneously with the winding layer.

In one embodiment, the step of winding the fiber reinforced epoxy resin around the outer wall of the reinforcing layer to form the wound layer specifically includes:

the fiber reinforced epoxy resin is wound on the cylinder body of the reinforcing layer in an annular winding mode, and then wound on the cylinder body and the seal head of the reinforcing layer in a spiral winding mode.

In one embodiment, the outer wall of the inner layer of the inner container is softened by heating through infrared, laser or high-temperature hot air blowing;

the fiber reinforced thermoplastic resin prepreg is heated and softened by infrared, laser or high-temperature hot air blowing.

In one embodiment, the fibers in the fiber reinforced thermoplastic resin prepreg are continuous fibers, and the fiber reinforced thermoplastic resin prepreg is wound on the outer wall of the inner liner layer in a spiral winding manner.

According to the technical scheme, the invention has the advantages and positive effects that:

the composite gas cylinder comprises a metal cylinder head, a plastic inner container and a winding layer wound on the outer wall of the plastic inner container. The plastic liner comprises a liner inner layer and a reinforcing layer formed on the outer wall of the liner inner layer, the liner inner layer is made of thermoplastic resin, the reinforcing layer is a fiber-reinforced thermoplastic resin layer, the reinforcing layer and the thermoplastic resin on the liner inner layer are designed into the same material, the reinforcing layer and the liner inner layer are fused, and the connecting strength between the reinforcing layer and the liner inner layer is increased. The winding layer is the fibre reinforced epoxy layer, the adhesion between winding layer and the enhancement layer has been strengthened to the chemical coupling effect between the epoxy through the winding layer and the fibre of enhancement layer, consequently, the adhesion between winding layer and the plastics inner bag has been strengthened, thereby the joint strength of metal bottle head and plastics inner bag linking department has been increased, consequently, guaranteed under the high pressure condition, the displacement of metal bottle head and plastics inner bag is synchronous, prevent the phenomenon that the interface of plastics inner bag and metal bottle head peeled off, thereby the quality of compound gas cylinder has been improved.

After the bonding force between the winding layer and the plastic inner container is increased, the composite gas cylinder is guaranteed to be in a bonding state between the plastic inner container and the winding layer all the time even after pressure circulation, the phenomenon that the plastic inner container of the composite gas cylinder bulges inwards in a pressure emptying state is avoided, and then the phenomenon that the plastic inner container bulges for many times is avoided, so that the plastic inner container is silvered and cracked, and the whole service life of the composite gas cylinder is prolonged.

Drawings

Fig. 1 is a partial structural schematic diagram of a composite gas cylinder in an embodiment of the invention.

Fig. 2 is a sectional view of a composite gas cylinder in an embodiment of the present invention.

Fig. 3 is a flow chart of a composite gas cylinder forming method in the embodiment of the invention.

The reference numerals are explained below: 11. a metal bottle head; 12. a plastic inner container; 121. an inner layer of the inner container; 122. a reinforcing layer; 13. a winding layer; 14. and an outer protective layer.

Detailed Description

Exemplary embodiments that embody features and advantages of the invention are described in detail below in the specification. It is to be understood that the invention is capable of other embodiments and that various changes in form and details may be made therein without departing from the scope of the invention and the description and drawings are to be regarded as illustrative in nature and not as restrictive.

For further explanation of the principles and construction of the present invention, reference will now be made in detail to the preferred embodiments of the present invention, which are illustrated in the accompanying drawings.

The invention provides a composite gas cylinder which can be used for storing and transporting liquefied petroleum gas, natural gas and other high-pressure media.

Referring to fig. 1 and 2, the composite gas cylinder in the present embodiment includes a plastic inner container 12, a metal head 11, a wrapping layer 13, and an outer protective layer 14. Only the structure at one end port of the composite cylinder is illustrated in fig. 1.

The metal bottle head 11 and the end part of the plastic inner container 12 are integrally formed. Specifically, the metal bottle head 11 is made of hard aluminum alloy, stainless steel or common alloy steel. When the metal bottle head 11 is made of common alloy steel, measures for preventing potential corrosion are taken at the connecting part of the metal bottle head 11 and the plastic inner container 12.

In one embodiment, the metal tip 11 includes a tip body and a disk-shaped flange protruding from the outer periphery of the tip body. The disc-shaped flange has a plurality of grooves arranged at intervals.

With continued reference to fig. 2, the plastic liner 12 includes a liner inner layer 121 and a reinforcement layer 122.

The inner liner 121 comprises a cylinder and end sockets connected to two ends of the cylinder. The cylinder body is in a cylindrical shape with two open ends and a hollow interior, the end sockets are in an oval shape, a spherical shape or a dish shape, the two ends of the cylinder body are closed by the end sockets, and the end sockets and the metal bottle heads 11 are integrally formed so that the metal bottle heads 11 are embedded in the end sockets.

The end socket and the cylinder body can be integrally formed, so that a splicing seam between the common cylinder body and the end socket is not formed. For convenience of description, the main body portion and the two end portions of the inner liner 121, which are integrally formed, are referred to as a cylinder and a cap, respectively, along with the names of the prior art. However, it is emphasized that the inner container layer 121 is divided into a cylinder and a sealing head in this embodiment, which are mainly distinguished according to the shape and position thereof, and do not represent the actual composition structure of the inner container layer 121.

The end socket and the cylinder body can also be connected by welding, so that a splicing seam between the common cylinder body and the end socket is formed.

In one embodiment, the inner periphery of the end socket of the inner liner layer 121 is provided with a groove, the groove is internally provided with a plurality of protrusions, and when the disk-shaped flange is accommodated in the groove, the protrusions are matched with the grooves, so that the primary connection between the plastic liner 12 and the metal bottle head 11 is realized, and the sealing performance between the plastic liner 12 and the metal bottle head 11 is enhanced.

The inner layer 121 of the inner container is directly contacted with a medium, and has the main functions of air tightness, corrosion resistance, temperature resistance and pressure resistance. Specifically, the material of the inner liner layer 121 is a thermoplastic resin. The thermoplastic resin may be polyamide and may also be high density polyethylene.

The reinforcing layer 122 is formed on the outer wall of the liner inner layer 121 and is fused and bonded with the liner inner layer 121. Therefore, when the composite gas cylinder is subjected to pressure, the reinforcing layer 122 bears a part of the pressure load, the pressure applied to the liner inner layer 121 is reduced, and the deformation resistance is further achieved. The reinforcing layer 122 is formed on the outer wall of the inner container inner layer 121, so that the connection strength of the joint of the metal bottle head 11 and the inner container inner layer 121 is increased, and therefore, when the inner container inner layer 121 deforms under the action of high pressure, the displacement of the metal bottle head 11 and the displacement of the inner container inner layer 121 are synchronous, the phenomenon that the metal bottle head 11 and the plastic inner container 12 are peeled off from each other at the interface is avoided, and the quality of the composite gas cylinder is improved.

The material of the reinforcing layer 122 is fiber reinforced thermoplastic resin, wherein the fiber may be glass fiber, and may also be carbon fiber or other fibers, and the type of the fiber is not limited herein, and may be selected according to practical applications.

In the present embodiment, the thermoplastic resin material of the reinforcement layer 122 is the same as the thermoplastic resin of the liner inner layer 121, and is, for example, polyamide. And before the reinforcing layer 122 is formed on the outer wall of the liner inner layer 121, the fiber reinforced thermoplastic resin and the outer wall of the liner inner layer 121 are heated and softened in advance, then the fiber reinforced thermoplastic resin is wound or sprayed on the outer wall of the liner inner layer 121, and finally the fiber reinforced thermoplastic resin is cured to obtain the fused and bonded reinforcing layer 122 and the liner inner layer 121. The thermoplastic resin of the reinforcing layer 122 and the thermoplastic resin of the liner inner layer 121 are compatible with each other and can be fused into a single body without any distinct interface, so that the fusion bonding force between the reinforcing layer 122 and the liner inner layer 121 is good. In other embodiments, the thermoplastic resin material of the reinforcement layer 122 and the thermoplastic resin material of the inner liner layer 121 may be two materials, for example, one of the thermoplastic resin material of the reinforcement layer 122 and the thermoplastic resin material of the inner liner layer 121 is polyamide, and the other is high density polyethylene.

The reinforcing layer 122 is formed on the liner inner layer 121 through a continuous filament winding process or a spraying process. The continuous fiber winding process includes the steps of firstly preparing fiber reinforced thermoplastic resin prepreg, wherein the fiber reinforced thermoplastic resin prepreg is formed by melting thermoplastic resin, infiltrating the fiber, enabling the thermoplastic resin to be uniformly wrapped on the surface of the fiber, and cooling to obtain the solid fiber reinforced thermoplastic resin prepreg. Before winding, the prepreg and the outer wall of the inner liner 121 need to be heated and softened in modes of infrared, laser or high-temperature hot air spraying and sweeping, so that the reinforcing layer 122 and the inner liner 121 are fused, and the connection strength between the reinforcing layer and the inner liner 121 is ensured.

The winding layer 13 is wound around the outer wall of the reinforcing layer 122 and is connected and fixed with the reinforcing layer 122. Specifically, the material of the winding layer 13 is fiber-reinforced epoxy resin. In this example, the fibers are carbon fibers and the epoxy resin is bisphenol a epoxy resin. The bisphenol A epoxy resin has high mechanical strength, good toughness and moderate viscosity.

In one embodiment, the outer wall of the reinforcing layer 122 is coated with epoxy resin, which is coupled with the fibers of the reinforcing layer 122 and bonded to the wrapping layer 13, so that the wrapping layer 13 is fixedly connected to the reinforcing layer 122. The epoxy resin coated on the outer wall of the reinforcing layer 122 and the epoxy resin coated on the outer wall of the winding layer 13 are made of the same type of material, so that the bonding force between the winding layer 13 and the reinforcing layer 122 is enhanced, and the epoxy resin coated on the outer wall of the reinforcing layer 122 and the fiber coupling connection of the reinforcing layer 122 are achieved, so that the bonding force between the winding layer 13 and the plastic inner container 12 is enhanced, and even after the composite gas cylinder is subjected to pressure circulation, the plastic inner container 12 and the winding layer 13 are always in a bonding state, the phenomenon that the plastic inner container 12 of the composite gas cylinder bulges inwards in a pressure emptying state is avoided, and further, after repeated bulging is avoided, the plastic inner container 12 is silvered and cracked, and the whole service life of the composite gas cylinder is prolonged.

After the adhesive force between the winding layer 13 and the plastic liner 12 is increased, the connection strength of the joint of the metal bottle head 11 and the plastic liner 12 is further increased, so that the metal bottle head 11 and the plastic liner 12 are ensured to be displaced synchronously under the high-pressure condition, the interface between the plastic liner 12 and the metal bottle head 11 is prevented from being peeled off, and the quality and the service life of the composite gas cylinder are improved.

The bonding between the epoxy resin and the reinforcing layer 122 is realized through the coupling effect between the epoxy resin and the fiber, and the bonding force between the epoxy resin and the reinforcing layer 122 is increased.

Specifically, the epoxy resin coated on the outer wall of the reinforcing layer 122 is bisphenol a epoxy resin, which is the same as the epoxy resin of the winding layer 13, so that the epoxy resin and the epoxy resin are better fused, and the bonding strength between the reinforcing layer 122 and the winding layer 13 is enhanced.

In another embodiment, the outer wall of the reinforcing layer 122 may not be coated with epoxy resin, and the wrapping layer 13 is directly bonded to the reinforcing layer 122 and coupled to the fibers of the reinforcing layer 122 through the epoxy resin of the wrapping layer 13 itself.

The outer protective layer 14 is wound around the outer wall of the winding layer 13. Specifically, the material of the outer protection layer 14 is glass fiber reinforced epoxy resin, and the epoxy resin of the outer protection layer 14 is the same as the epoxy resin of the winding layer 13, so that the two layers are well fused, and the bonding force between the outer protection layer 14 and the winding layer 13 is enhanced.

According to the composite gas cylinder, the thermoplastic resin of the reinforcing layer 122 and the inner container inner layer 121 is designed into the same material, so that the reinforcing layer 122 and the inner container inner layer 121 are fused into a whole without an obvious interface, and the epoxy resin coated on the outer wall of the reinforcing layer 122 and the fiber of the reinforcing layer 122 have a coupling effect, so that the bonding force between the winding layer 13 and the plastic inner container 12 is enhanced, the plastic inner container 12 and the winding layer 13 are always in a bonding state even after the composite gas cylinder is subjected to pressure circulation, the phenomenon that the plastic inner container 12 of the composite gas cylinder bulges inwards in a pressure emptying state is avoided, the phenomenon that the plastic inner container 12 bulges inwards after being repeatedly bulged is avoided, and the service life of the whole composite gas cylinder is prolonged.

After the adhesive force between the winding layer 13 and the plastic liner 12 is increased, the connection strength of the joint of the metal bottle head 11 and the plastic liner 12 is further increased, so that the metal bottle head 11 and the plastic liner 12 are ensured to be displaced synchronously under high pressure, and the phenomenon of interface peeling between the plastic liner 12 and the metal bottle head 11 is prevented.

Referring to fig. 3, the invention also provides a method for forming a composite gas cylinder, comprising the following steps:

s1, forming the liner inner layer 121 from thermoplastic resin, and integrally forming the metal bottle head 11 and the liner inner layer 121 during the forming process of the liner inner layer 121.

In one embodiment, the inner container inner layer 121 is formed by a rotational molding process, and specifically includes:

s101, preheating a metal bottle head 11;

s102, placing the preheated metal bottle head 11 in a rotational molding film cavity, and filling thermoplastic resin into the rotational molding film cavity to integrally form the metal bottle head 11 and the inner liner 121.

After the metal bottle head 11 is preheated, the groove on the disc-shaped flange of the metal bottle head 11 can be filled with thermoplastic resin, and the connection strength between the formed metal bottle head 11 and the inner container inner layer 121 is ensured.

In another embodiment, the inner container inner layer 121 is formed by an injection molding process, and specifically, the steps include:

s111, preparing a cylinder body of the inner container inner layer 121;

s112, placing the metal bottle head 11 in an injection molding film cavity, and filling thermoplastic resin into the injection molding film cavity to integrally form the metal bottle head 11 and the end socket of the inner liner layer 121.

S113, welding the end socket of the inner liner 121 and the cylinder body in a hot melting mode.

S2, heating and softening the outer wall of the inner liner layer 121.

The heating and softening of the inner liner layer 121 can be achieved by means of infrared, laser or high-temperature hot air spraying.

And S3, wrapping the fiber reinforced thermoplastic resin prepreg subjected to heating softening on the outer wall of the liner inner layer 121 subjected to heating softening, and molding to obtain the reinforcing layer 122.

Specifically, the method comprises the following steps:

s31, providing raw material fibers and thermoplastic resin, and melting the thermoplastic resin to uniformly wrap the fibers to obtain the fiber-reinforced thermoplastic resin prepreg.

And S32, heating and softening the fiber reinforced thermoplastic resin prepreg. Wherein the heating and softening are carried out by means of infrared, laser or high-temperature hot air spraying.

Specifically, the heating softening of the inner liner layer 121 may be performed simultaneously with the heating softening of the fiber-reinforced thermoplastic resin prepreg, so as to sufficiently ensure that both are in a softened state in the next process.

And S33, wrapping the outer wall of the inner liner 121 with the fiber-reinforced thermoplastic resin prepreg subjected to heating softening, and molding to obtain the reinforcing layer 122.

In one embodiment, the fiber reinforced thermoplastic resin prepreg that is softened by heating is wound around the outer wall of the inner liner 121. Specifically, the winding mode is spiral winding, and the end socket and the cylinder of the inner liner 121 are both wound.

The metal bottle head 11 is firmly embedded into the inner container layer 121 through the winding effect of the reinforcing layer 122, and the effect similar to the effect of tightening through a rope ensures that the inner container layer 121 and the metal bottle head 11 are synchronously displaced under the action of high pressure, so that the metal bottle head 11 is prevented from being peeled from the inner container layer 121.

In another embodiment, the fiber-reinforced thermoplastic resin prepreg after heating and softening is wrapped on the outer wall of the inner liner 121 by spraying.

S4, winding the fiber reinforced epoxy resin around the outer wall of the reinforcing layer 122 to form a wound layer 13.

In one embodiment, the method specifically includes:

s401, processing the outer surface of the reinforcing layer 122 to expose the fibers on the outer surface of the reinforcing layer 122.

And S402, coating epoxy resin on the exposed fibers on the outer surface of the reinforcing layer 122, wherein the epoxy resin is coupled with the exposed fibers.

And S403, winding the fiber reinforced epoxy resin on the cylinder body of the reinforcing layer 122 in an annular winding mode, and then winding the fiber reinforced epoxy resin on the cylinder body and the end socket of the reinforcing layer 122 in a spiral winding mode.

The exposed fiber and the epoxy resin are coupled and chelated greatly, the epoxy resin of the winding layer 13 is solidified and bonded with the epoxy resin coated on the outer surface of the reinforcing layer 122, and therefore the bonding force between the reinforcing layer 122 and the winding layer 13 is increased, the phenomenon that the inner liner inner layer 121 of the composite gas cylinder bulges in the pressure emptying state is reduced, and the service life of the composite gas cylinder is prolonged.

In another embodiment, the method specifically comprises the following steps:

s411, processing the outer surface of the reinforcing layer 122 to expose the fibers on the outer surface of the reinforcing layer 122.

S412, winding the fiber reinforced epoxy resin on the cylinder of the reinforcing layer 122 in an annular winding mode, and then winding the fiber reinforced epoxy resin on the cylinder and the end socket of the reinforcing layer 122 in a spiral winding mode.

The exposed fiber is coupled with the epoxy resin of the winding layer 13, the winding layer 13 is bonded with the reinforcing layer 122 through the coupling effect of the epoxy resin and the fiber, and the bonding force between the winding layer 13 and the reinforcing layer 122 is increased.

S5, the outer protective layer 14 is formed by winding glass fiber/epoxy resin around the outer periphery of the winding layer 13.

Specifically, the method comprises the following steps:

s51, providing glass fiber and epoxy resin as raw materials of the outer protective layer 14, and melting the epoxy resin to uniformly wrap the glass fiber to obtain the glass fiber/epoxy resin material.

And S52, winding the glass fiber/epoxy resin material on the outer wall of the winding layer 13 to obtain the outer protection layer 14, the winding layer 13 and the plastic inner container 12.

S6, curing the outer protective layer 14, the winding layer 13 and the epoxy resin at the same time.

Specifically, the epoxy resin of the winding layer 13 and the epoxy resin of the outer protection layer 14 are the same epoxy resin and are used in sequence, the total service time is not more than 2 hours, and the epoxy resin is cured at the same time after the winding of the outer protection layer 14 is completed, so that the epoxy resin, the epoxy resin of the winding layer 13 and the epoxy resin of the outer protection layer 14 are integrally formed, the bonding force among the plastic inner container 12, the winding layer 13 and the outer protection layer 14 is improved, the plastic inner container 12 and the winding layer 13 are in a bonding state after the composite gas cylinder is subjected to pressure circulation for a long time, and the service life of the composite gas cylinder is prolonged.

While the present invention has been described with reference to several exemplary embodiments, it is understood that the terminology used is intended to be in the nature of words of description and illustration, rather than of limitation. As the present invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, but rather should be construed broadly within its spirit and scope as defined in the appended claims, and therefore all changes and modifications that fall within the meets and bounds of the claims, or equivalences of such meets and bounds are therefore intended to be embraced by the appended claims.