CN109578799B

CN109578799B - Large-scale high-pressure storage and transportation gas cylinder liner and manufacturing method thereof

Info

Publication number: CN109578799B
Application number: CN201811600529.1A
Authority: CN
Inventors: 王东坡; 马世成; 汪宇羿; 赵文龙; 张月倩; 孙昂
Original assignee: Aerospace Research Institute of Materials and Processing Technology
Current assignee: Aerospace Research Institute of Materials and Processing Technology
Priority date: 2018-12-26
Filing date: 2018-12-26
Publication date: 2020-08-11
Anticipated expiration: 2038-12-26
Also published as: CN109578799A

Abstract

The invention provides a large-scale high-pressure storage and transportation gas cylinder liner and a manufacturing method thereof, wherein the gas cylinder liner is an integrated seamless aluminum alloy liner with one end sealed, the other end closed and formed end socket and a bottle opening, the aluminum alloy liner comprises a straight cylinder section, and the end sealed and the end socket which are respectively positioned at two ends of the straight cylinder section, and the bottle opening is positioned on the end socket; the length of the aluminum alloy inner container is 5-13m, and the nominal outer diameter of the straight cylinder section is phi 300-phi 850 mm. The invention adopts the plate blank as the raw material, generally adopts the spinning processing method, has no welding line on the whole product, simple preparation process, convenient operation, low energy consumption and little pollution, and has less loss of the raw material in the manufacturing process. The aluminum alloy inner container processed by the manufacturing method has the characteristics of overlarge size, high reliability, thin wall and light weight; the material has uniform and compact tissue, excellent integral strength effect and high pressure resistance, and has important significance for manufacturing the oversized high-pressure gas cylinder.

Description

Large-scale high-pressure storage and transportation gas cylinder liner and manufacturing method thereof

Technical Field

The invention belongs to the technical field of high-pressure containers, and particularly relates to a large-scale high-pressure storage and transportation gas cylinder liner and a manufacturing method thereof.

Background

The high-pressure gas cylinder is widely used in various industries of national economy such as industrial and mining production, construction, transportation, ocean, aviation, medical treatment, military and the like. The capacity, wall thickness, and fabrication process and materials of a high pressure gas cylinder all affect the performance of the high pressure gas cylinder. Such as natural gas and hydrogen, is a clean energy source that is heavily developed and widely used worldwide. The use of 20-30MP high pressure gas cylinders for storage and transportation and the use of Compressed Natural Gas (CNG), compressed hydrogen and other compressed industrial gases is currently the primary means by which these gases are transported from main pipelines to points of use, filling stations, etc.

At present, the carbon fiber fully-wound high-pressure gas cylinder with the aluminum alloy liner has a plurality of advantages, gradually replaces the traditional steel gas cylinder, and becomes the mainstream product of the high-pressure gas cylinder in the world. Its advantages are as follows:

(1) the weight is greatly reduced; the gas cylinder compositely wound by the aluminum alloy liner has the material thickness of 50-70% of that of the steel cylinder and lower density under the same performance, so that the weight of the gas cylinder is only 35-40% of that of the traditional steel cylinder.

(2) The damage safety is good; the aluminum alloy inner container carbon fiber fully-wound gas cylinder is reinforced by the aluminum alloy inner container and the carbon fiber composite material, fibers per square centimeter are as many as thousands of fibers, when the gas cylinder is overloaded and a small amount of fibers are broken, the load of the gas cylinder can be rapidly distributed on the fibers which are not damaged, so that the gas cylinder cannot lose the bearing capacity in a short period or even a long period, and the safety is greatly improved.

(3) The shock absorption is good; the interface of the fiber and the resin matrix in the composite material has shock absorption capacity, good shock damping and high sound-shock fatigue resistance.

(4) Compared with the complex process required by a seamless steel gas cylinder, the fiber winding process is more flexible, easy to change, simpler in process, easy to realize automation and far lower in energy consumption than the production process of the steel gas cylinder.

For example, the carbon fiber fully-wound gas cylinder with the aluminum alloy inner container with the outer diameter of phi 300-phi 850mm and the length of 5-13m is mainly used as a large-volume high-pressure gas cylinder for storage and transportation of large-scale natural gas transportation tank cars, a gas station, a CNG transport ship, an industrial high-purity gas and the like.

However, limited by material production and technical capability, the carbon fiber fully-wound gas cylinder with the aluminum alloy liner of which the length is more than 5m cannot be produced in China at present, and the core problem is that the aluminum alloy liner cannot be manufactured.

Under the above background, in order to greatly improve the storage and transportation capability of natural gas and hydrogen tank cars and further master the key technologies and products of large storage and transportation devices such as compressed natural gas, hydrogen and mixed gas with independent property rights, the development of large high-pressure storage and transportation gas cylinder liner products with the characteristics of large diameter, long length, light weight, high reliability and the like is urgently needed.

Disclosure of Invention

The invention aims to provide an inner container of a large-scale high-pressure storage and transportation gas cylinder and a manufacturing method thereof. At least solves the problems of small volume, overweight and poor reliability of the prior high-pressure gas cylinder.

In order to achieve the above purpose, the invention provides the following technical scheme:

a large-scale high-pressure storage and transportation gas cylinder liner is an aluminum alloy liner with an integrated seamless structure, wherein one end of the aluminum alloy liner is sealed, the other end of the aluminum alloy liner is closed to form a seal head and a bottle opening, the aluminum alloy liner comprises a sealed bottom, a straight cylinder section, a seal head and a bottle opening, the sealed bottom and the seal head are respectively positioned at two ends of the straight cylinder section, and the bottle opening is positioned on the seal head; the length of the inner container of the large high-pressure storage and transportation gas cylinder is 5-13m, the nominal outer diameter of the straight cylinder section is phi 300-phi 850mm, and the rated pressure of the high-pressure gas cylinder is 20-30 Mpa.

Preferably, the wall thickness of the straight cylinder section is 3-10mm, and the integral straightness of the straight cylinder section is not more than 0.5 mm/m;

preferably, the tolerance of the wall thickness of the straight cylinder section is less than or equal to +/-0.15 mm;

preferably, the local straightness at any straight section position of the straight cylinder section is not more than 0.5mm/300 mm;

still preferably, the roundness of any position of the straight cylinder section is not more than 0.5 mm;

still preferably, the roughness of the inner surface of the straight cylinder section is less than Ra1.6 μm, and the roughness of the outer surface of the straight cylinder section is less than Ra3.2 μm.

Preferably, the structure type of the end enclosure is an ellipsoidal end enclosure, a disc-shaped end enclosure or a hemispherical end enclosure, the structure type of the back enclosure is the same as that of the end enclosure, the thickness of the end enclosure is uniformly and gradually thickened from the edge to the bottle opening, and the thickness of the back enclosure is uniformly and gradually thickened from the edge to the center of the back enclosure;

preferably, the thickness of the end socket is uniformly and gradually thickened from 5-8mm of the edge to 10-15mm of the bottle mouth part;

preferably, the thickness of the back cover is uniformly and gradually thickened from 5-8mm of the edge to 10-20mm of the center of the back cover;

still preferably, the length of bottleneck is 40mm, the external diameter of bottleneck is 50mm, the internal diameter of bottleneck is 28 mm.

The manufacturing method of the large-scale high-pressure storage and transportation gas cylinder liner preferably comprises the following steps:

s1, performing integral reverse extrusion forming on the blank with the back cover, selecting an aluminum ingot as the blank, and adopting a heating reverse extrusion process combined with turning and boring processes to prepare a seamless pipe composed of the back cover and a straight barrel section with an opening at one end;

s2, preparing an aluminum alloy inner container spinning pipe;

s3, grinding the surfaces of the back cover and the straight cylinder section;

and S4, performing flaw detection on the back cover and the straight cylinder section, performing ultrasonic flaw detection on the back cover and the straight cylinder section of the aluminum alloy liner spinning tube obtained in the step S3, and detecting defects of air holes, inclusions, pits and microcracks on the inner surface.

S5, spinning and forming the end socket and the bottle mouth;

s6, processing a central hole of the bottle mouth;

s7, curved surface flaw detection;

s8, grinding the inner surface of the curved surface;

s9, performing heat treatment, namely performing T6 process treatment on the spinning forming piece C obtained in the step S8 to obtain a large-scale high-pressure storage and transportation gas cylinder liner blank;

s10, processing a bottle opening, namely machining the inner diameter and the outer diameter of the bottle opening of the large-scale high-pressure storage and transportation gas bottle inner container blank obtained in the step S9 by using an overlong bottle opening processing center, and processing internal threads of the bottle opening to obtain a large-scale high-pressure storage and transportation gas bottle inner container;

and S11, cleaning the inner container.

Preferably, in the manufacturing method of the liner of the large-sized high-pressure storage and transportation gas cylinder, the step S1 specifically includes the following steps:

s1a, heating the aluminum ingot, and preheating the aluminum ingot to be extruded to 200-400 ℃;

s1b, heating a die, and preheating an outer extrusion die and an inner extrusion rod to 200-400 ℃;

s1c, performing extrusion forming, namely placing an aluminum ingot in an extrusion outer die, and manufacturing a blank into a prefabricated pipe blank with a sealed bottom through multiple times of extrusion under the condition of continuous heating and heat preservation;

s1d, machining the outer surface of the prefabricated pipe blank to the size required by spinning the blank by adopting a turning method;

s1e, processing the inner surface of the prefabricated pipe blank to the size required by the spinning blank by adopting a boring method;

preferably, in step S1a, the aluminum ingot is preheated using a heating furnace;

still preferably, in step S1c and step S1d, the size of the back cover part is directly processed to the size required by the product;

still preferably, the heating in steps S1b-S1d is combustion flame heating with oxygen, propane/LNG.

In the manufacturing method of the large-scale high-pressure storage and transportation gas cylinder liner, preferably, the heating and back-extrusion equipment is a vertical extruder with extrusion force not less than 6000 tons; the extrusion outer die is provided with a back cover, and the length of the inner extrusion rod is 1.6-1.7 m;

preferably, the shape of the bottom cover of the outer die is the same as that of the bottom cover of the large-scale high-pressure storage and transportation gas cylinder liner, and 5-10mm of allowance is reserved in the thickness direction;

still preferably, the type of the heating and back-extruding device is a numerical control oil press.

In the method for manufacturing the liner of the large-sized high-pressure storage and transportation gas cylinder, preferably, the step S2 is: performing multi-pass tension external spinning forming treatment on the straight tube section of the seamless tube manufactured in the step S1 by using an overlong tube body tension spinning device to obtain an aluminum alloy inner container spinning tube; the method specifically comprises the following steps:

s21, spinning and forming the straight tube section of the aluminum alloy inner container spinning tube, and performing 3-5 times of spinning processes on the straight tube section of the seamless tube material prepared in the step S1 by adopting an ultralong tube body tension spinning device and a tension three-spinning wheel staggered pitch forward spinning method to obtain a spinning piece A; during spinning, a floating core mould with the length of 1-2m is adopted for spinning auxiliary processing;

s22, performing fixed-length processing on the spinning pipe of the aluminum alloy liner, namely performing fixed-length processing on the spinning piece A obtained in the step S21 by using an ultra-long double-head sawing machine to obtain the spinning pipe of the aluminum alloy liner;

s23, cleaning the aluminum alloy inner container spinning pipe, and cleaning the aluminum alloy inner container spinning pipe obtained in the step S22 by using an ultra-long cleaning machine;

preferably, the offset amount in the three-wheel offset forward spinning method in the step S21 is set to 6-12 mm;

still preferably, the cleaning machine in the step S23 is a rotary spray cleaning machine or an ultrasonic cleaning machine;

preferably, the cleaning of the one-end bottom-sealed aluminum alloy liner spinning tube is completed by a neutral cleaning agent heated to 30-45 ℃;

preferably, the residual water stain on the surface is removed by adopting an inward-extending drying device after the spinning tube with the aluminum alloy liner with one end being sealed is cleaned.

In the manufacturing method of the large-sized high-pressure storage and transportation gas cylinder liner, preferably, in the spinning manufacturing process of the spinning part a in the step S21, the traction force is used for drawing the bottom sealing end of the seamless pipe, and the traction direction of the traction force is opposite to the flowing direction of the material; the traction force is a constant force, and the traction speed is adaptive to the deformation speed of the material; the axial direction of the bottom sealing end is fixed on the traction mechanism, so that the radial freedom of the bottom sealing end is ensured; and the positioning device is adopted to fix and support the other end of the seamless pipe in the radial direction, so that the axial freedom of the other end of the seamless pipe is ensured.

In the method for manufacturing the liner of the large-sized high-pressure storage and transportation gas cylinder, preferably, the step S5 is: spinning forming of the end socket and the bottle mouth is carried out on the opening of the aluminum alloy liner spinning tube by adopting a heating closing-up spinning machine, and a spinning forming piece B is obtained; the method specifically comprises the following steps:

s51, clamping, namely clamping the aluminum alloy liner spinning tube by adopting a double-clamping-opening split type hollow tool and an automatic clamping and centering device behind the main shaft;

s52, heating, namely heating the spinning part to be closed of the spinning pipe of the aluminum alloy liner to 180 DEG and 390 ℃;

s53, forming and spinning the end socket and the bottle mouth, and performing multi-pass closing-up spinning on the aluminum alloy liner spinning tube heated in the step S42 by adopting a single-side X-line, Z-line and rotary three-way interpolation type closing-up spinning machine to obtain a spinning forming piece B;

preferably, the heating in step S52 is performed by combustion flame heating using oxygen, propane/LNG.

Preferably, in the method for manufacturing the large-sized high-pressure storage and transportation cylinder liner, the method comprises the following steps:

s6, processing a center hole of the bottle mouth, namely, processing the center hole of the bottle mouth of the spinning formed piece B obtained in the step S5 by a machine to obtain a spinning formed piece C;

s7, performing curved surface flaw detection, performing closing quality flaw detection on the spinning formed part C obtained in the step S6, and detecting whether the position of a seal head has machining defects of orange peel and folding;

s8, grinding the inner surface of the curved surface, and grinding the defects of the inner surface of the end socket found in the step S7 by using an end socket inner surface grinding machine tool according to the flaw detection result to obtain a spinning formed part C with qualified quality;

wherein, preferably, the step S9 includes the following steps:

s91, clamping, namely clamping the spinning formed part C by 3-5 split heat treatment tools at equal intervals;

s92, quenching, namely putting the spinning formed part C clamped in the step S91 into a quenching furnace for quenching, heating the spinning formed part C to 525-;

s93, aging treatment, namely transferring the quenched spinning formed part C to an aging furnace for aging treatment, and finally preserving heat for 6-10 hours in an environment of 160-200 ℃ to prepare a large-scale high-pressure storage and transportation gas cylinder liner blank;

preferably, the quenching and aging are carried out by heat treatment in a horizontal continuous quenching and aging furnace.

Compared with the closest prior art, the technical scheme provided by the invention has the following beneficial effects:

the manufacturing method of the large-scale high-pressure storage and transportation gas cylinder liner provided by the invention generally adopts a spinning processing method, has the advantages of simple preparation process, convenient operation, low energy consumption and little pollution, has less loss of raw materials in the whole manufacturing process, and saves the cost of raw materials. The large-scale high-pressure storage and transportation gas cylinder liner processed by the manufacturing method has the characteristics of overlarge size, high reliability, thin wall and light weight, the nominal outer diameter reaches phi 300-phi 850mm, and the wall thickness of a straight cylinder section is 3-10 mm; the material has uniform and compact tissue, excellent integral strength effect and high pressure resistance. The invention creatively adopts an aluminum ingot as a blank and adopts the integral backward extrusion process to prepare a semi-finished product, so that the internal structure of the prepared aluminum alloy liner is compact and uniform, when a straight cylinder section with an overlong size is processed, one end of the blank is provided with traction force and is matched with a floating core mold to carry out integral extension processing, so that the prepared aluminum alloy liner can meet the requirement of the ultra-large size (5-13 meters) while meeting the precision requirement, and the volume is far higher than that of the existing standard aluminum alloy liner; the method has important significance for preparing the inner liner of the large-scale high-pressure storage and transportation gas cylinder.

Drawings

FIG. 1 is a schematic structural diagram of an inner container of a large-scale high-pressure storage and transportation gas cylinder in the embodiment of the invention;

fig. 2 is a flow chart of a manufacturing method of the inner container of the large-scale high-pressure storage and transportation gas cylinder in the embodiment of the invention.

In the figure: 1. sealing the bottom; 2. a straight cylinder section; 3. sealing the end; 4. and (5) opening the bottle.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments that can be derived by one of ordinary skill in the art from the embodiments given herein are intended to be within the scope of the present invention.

The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings. It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.

In the description of the present invention, the terms "connected" and "connected" used in the present invention should be interpreted broadly, for example, as a fixed connection or a detachable connection; they may be directly connected or indirectly connected through intermediate members, and specific meanings of the above terms will be understood by those skilled in the art as appropriate.

The invention provides a large-scale high-pressure storage and transportation gas cylinder liner, which is formed by processing a round or square plate blank by the manufacturing method; as shown in fig. 1, the large-scale high-pressure storage and transportation gas cylinder liner is an aluminum alloy liner with an integrated seamless structure, wherein one end of the aluminum alloy liner is sealed with a bottom 1, the other end of the aluminum alloy liner is sealed with a forming seal head 3 and a bottle opening 4, the aluminum alloy liner comprises the bottom 1, a straight cylinder section 2, the seal head 3 and the bottle opening 4, the bottom 1 and the seal head 3 are respectively positioned at two ends of the straight cylinder section 2, and the bottle opening 4 is positioned on. The structure type of the end socket 3 is an ellipsoidal end socket 3, a disc-shaped end socket 3 or a hemispherical end socket 3, the structure type of the back cover 1 is the same as that of the end socket 3, and in the embodiment of the invention, the structure types of the back cover 1 and the end socket 3 are ellipsoidal; the length of the inner container of the large high-pressure storage and transportation gas cylinder is 5-13m (such as 5.5m, 6m, 6.5m, 7m, 7.5m, 8m, 8.5m, 9m, 9.5m, 10m, 10.5m, 11m, 11.5m, 12m and 12.5m), the nominal outer diameter of the straight cylinder section 2 is phi 300-phi 850mm (such as phi 350mm, phi 400mm, phi 450mm, phi 500mm, phi 550mm, phi 600mm, phi 650mm, phi 700mm, phi 750mm and phi 800mm), the wall thickness of the straight cylinder section 2 is 3-10mm (such as 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, 9mm and 9.5mm), and the integral straightness of the straight cylinder section 2 is not more than 0.5 mm/m; the tolerance of the wall thickness of the straight cylinder section 2 is less than or equal to +/-0.15 mm; the local straightness at any straight section position of the straight cylinder section 2 is not more than 0.5mm/300 mm; the roundness of any position of the straight cylinder section 2 is not more than 0.5 mm; the roughness of the inner surface of the straight cylinder section 2 is less than Ra1.6 μm, and the roughness of the outer surface of the straight cylinder section 2 is less than Ra3.2 μm. The thickness of the seal head 3 is uniformly gradually thickened from the edge to the bottle mouth 4, and the thickness of the back cover 1 is uniformly gradually thickened from the edge to the center of the back cover 1; the thickness of the seal head 3 is uniformly and gradually thickened from 5-8mm (such as 5.2mm, 5.4mm, 5.6mm, 5.8mm, 6mm, 6.2mm, 6.4mm, 6.6mm, 6.8mm, 7mm, 7.3mm, 7.6mm and 7.8mm) of the edge to 10-15mm (such as 10.5mm, 11mm, 11.5mm, 12mm, 12.5mm, 13mm, 13.5mm, 14mm and 14.5mm) of the position of the bottle mouth 4; the thickness of the back cover 1 is uniformly thickened from 5-8mm (such as 5.2mm, 5.4mm, 5.6mm, 5.8mm, 6mm, 6.2mm, 6.4mm, 6.6mm, 6.8mm, 7mm, 7.3mm, 7.6mm, 7.8mm) of the edge to 10-20mm (such as 10.5mm, 11mm, 11.5mm, 12mm, 12.5mm, 13mm, 13.5mm, 14mm, 14.5mm, 15.5mm, 16mm, 16.5mm, 17mm, 17.5mm, 18.mm, 18.5mm, 19mm, 19.5mm) of the center of the back cover 1; the length of the mouth 4 is 40mm, the outer diameter of the mouth 4 is 50mm, and the inner diameter of the mouth 4 is 28 mm. The high-pressure gas cylinder has a rated pressure of 20-30MPa (such as 21MPa, 22MPa, 23MPa, 24MPa, 25MPa, 26MPa, 27MPa, 28MPa, and 29 MPa).

As shown in fig. 2, the invention also provides a method for manufacturing the inner liner of the large-scale high-pressure storage and transportation gas cylinder, which comprises the following steps:

s1, performing integral reverse extrusion forming on the blank with the back cover 1, and adopting a heating reverse extrusion process combined with turning and boring processes to prepare a seamless pipe consisting of the back cover 1 and a straight barrel section 2 with an opening at one end; the method specifically comprises the following steps:

s1a, heating an aluminum ingot, and preheating the aluminum ingot to be extruded to 400 ℃ by adopting a heating furnace (for example, 220 ℃, 240 ℃, 260 ℃, 280 ℃, 300 ℃, 320 ℃, 340 ℃, 360 ℃ and 380 ℃), wherein in the embodiment of the invention, a cylindrical aluminum ingot is used as an extrusion blank;

s1b, heating the die, namely preheating the outer extrusion die and the inner extrusion rod to 200-400 ℃ (such as 220 ℃, 240 ℃, 260 ℃, 280 ℃, 300 ℃, 320 ℃, 340 ℃, 360 ℃ and 380 ℃) by adopting a mode of combustion flame heating by oxygen and propane/LNG;

s1c, performing extrusion forming, namely placing an aluminum ingot in an extrusion outer die, starting a backward extrusion device to extrude the blank for multiple times to form a prefabricated pipe blank with a sealing bottom 1, and continuously heating and preserving heat in the extrusion process;

s1d, machining the outer surface of the prefabricated blank to the size required by spinning blank by adopting a turning method, so that the outer size of the back cover 1 part reaches the outer size of the product back cover 1;

s1e, machining the inner surface of the prefabricated blank to the required size of the spinning blank by adopting a boring method, so that the inner size of the back cover 1 part reaches the inner size of the product back cover 1.

In the embodiment of the invention, the back extrusion equipment is a vertical extruder with extrusion force not less than 6000 tons; the vertical extruding machine belongs to a numerical control oil press. The extrusion outer die is provided with a sealing bottom 1, the shape of the sealing bottom 1 of the extrusion outer die is the same as that of the sealing bottom 1 of the large-scale high-pressure storage and transportation gas cylinder liner, a margin of 5-10mm (such as 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, 9mm and 9.5mm) is reserved in the thickness direction, and after extrusion, the margin is removed by adopting a turning process, so that the external shape and size of the sealing bottom 1 part reach the external size of the sealing bottom 1 of the product; the length of the internal extrusion rod is 1.6-1.7 m.

S2, preparing the aluminum alloy inner container spinning pipe, and performing multi-pass spinning forming treatment on the straight barrel section 2 of the seamless pipe prepared in the step S1 by adopting an ultra-long barrel tension spinning device to obtain the aluminum alloy inner container spinning pipe; the method specifically comprises the following steps:

s21, carrying out spinning forming on the straight tube section 2 of the aluminum alloy liner spinning tube, and carrying out 3-5 times (for example, 3 times, 4 times and 5 times) spinning processes on the seamless tube material prepared in the step S1 by adopting an ultralong tube body tension spinning device and a tension three-spinning wheel staggered pitch forward spinning method to obtain a spinning part A; the spinning is carried out by using a floating core mould with the length of 1-2m (such as 1.1m, 1.2m, 1.3m, 1.4m, 1.5m, 1.6m, 1.7m, 1.8m and 1.9m) for spinning auxiliary processing, the axial position of the floating core mould is not changed during spinning, and the offset in the tension three-spinning wheel offset forward spinning method is set to be 6-12mm (such as 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, 9mm, 9.5mm, 10mm, 10.5mm, 11mm and 11.5 mm); the total deformation of the seamless pipe after spinning treatment is 55-70%, and in the embodiment of the invention, when the total deformation is more than 70%, intermediate annealing treatment is carried out. The spinning piece A is a straight cylinder with the same thickness of one end sealing bottom 1 or a straight cylinder section 2 with one end sealing bottom 1 and one end provided with an outer annular end frame. In the spinning process of the step, traction force is adopted to pull the back cover 1 end of the seamless pipe, and the traction direction of the traction force is opposite to the flowing direction of the material; the traction force is constant force, and the traction speed is adaptive to the deformation speed of the material; the axial direction of the end of the back cover 1 is fixed on a traction mechanism to ensure the radial freedom of the end of the back cover 1; and the positioning device is adopted to fix and support the other end of the seamless pipe in the radial direction, so that the axial freedom of the other end of the seamless pipe is ensured.

S22, performing fixed-length processing on the spinning pipe of the aluminum alloy liner, namely performing fixed-length processing on the spinning piece A obtained in the step S21 by using an ultra-long double-head sawing machine to obtain the spinning pipe of the aluminum alloy liner; in the embodiment of the invention, the saw blade is a special aluminum alloy saw blade.

S23, cleaning the aluminum alloy inner container spinning tube, and adding a neutral cleaning agent with the temperature of 30-45 ℃ (such as 31 ℃, 32 ℃, 33 ℃, 34 ℃, 35 ℃, 36 ℃, 37 ℃, 38 ℃, 39 ℃, 40 ℃, 41 ℃, 42 ℃, 43 ℃ and 44 ℃) into an ultralong rotary spray cleaning machine or an ultrasonic cleaning machine to clean the aluminum alloy inner container spinning tube obtained in the step S22; and after cleaning, removing residual water stains on the surface by adopting an inward-extending drying device.

S3, grinding the inner surfaces of the back cover 1 and the straight cylinder section 2, and grinding the inner surface defects, the scratches and the damages of the inner and outer surfaces of the back cover 1 and the straight cylinder section 2 found in the step S3 by adopting a special ultra-long numerical control inner and outer circle grinding machine tool; the method specifically comprises the following steps:

s31, grinding the outer surface of the aluminum alloy inner container spinning tube by using a cloth abrasive belt;

s32, carrying out rough grinding on the inner surface of the aluminum alloy inner container spinning tube by using a millennium grinding wheel;

and S33, finely grinding the inner surface of the aluminum alloy inner container spinning tube by using a scouring pad wheel.

And S4, performing flaw detection on the back cover 1 and the straight cylinder section 2, performing ultrasonic flaw detection on the back cover 1 and the straight cylinder section 2 of the aluminum alloy liner spinning tube obtained in the step S3, and detecting defects such as air holes, inclusions, pits, microcracks and the like on the inner surface.

S5, spinning and forming the end socket 3 and the bottle mouth 4, wherein the end socket 3 and the bottle mouth 4 are spun and formed at the opening of the aluminum alloy liner spinning pipe by adopting a heating closing spinning machine to obtain a spinning and forming piece B; the method specifically comprises the following steps:

s52, carrying out flame spraying and heating on the spinning part to be closed of the spinning pipe of the aluminum alloy liner to 390 ℃ (such as 200 ℃, 220 ℃, 240 ℃, 260 ℃, 280 ℃, 300 ℃, 320 ℃, 340 ℃, 360 ℃ and 380 ℃) by adopting oxygen and propane/LNG combustion;

s53, forming and spinning the end socket 3 and the bottle mouth 4, and performing 10-18-pass closing-spinning on the aluminum alloy liner spinning tube heated in the step S52 by adopting a one-side X-line, Z-line and rotary three-way interpolation type closing-spinning machine to obtain a spinning forming piece B; in the spinning process, the 1 st to 8 th steps of closing spinning are provided with reverse spinning and are used for thickening the 4 parts of the bottle mouth; the thickness of the end socket 3 of the prepared spinning forming piece B is uniformly and gradually thickened from 5-8mm (such as 5.2mm, 5.4mm, 5.6mm, 5.8mm, 6mm, 6.2mm, 6.4mm, 6.6mm, 6.8mm, 7mm, 7.3mm, 7.6mm and 7.8mm) of the edge to 10-15mm (such as 10.5mm, 11mm, 11.5mm, 12mm, 12.5mm, 13mm, 13.5mm, 14mm and 14.5mm) of the position of the bottle mouth 4;

s6, processing a central hole of 4 bottle mouths, and clamping a spinning forming piece B by adopting 2-3 split self-clamping devices fixed on a machine tool workbench; machining a center hole of the bottle opening 4 of the spinning forming piece B obtained in the step S5 by using a special ultra-long bottle opening 4 machining center to obtain a spinning forming piece C; ready for subsequent T6 processing;

s7, performing curved surface flaw detection, performing closing quality flaw detection on the spinning formed part C obtained in the step S4 by adopting a special curved surface ultrasonic automatic flaw detector, and detecting whether machining defects such as orange peel and folding exist at the position of the end socket 3;

s71, clamping a spinning formed part C by adopting a double-clamping-opening split type hollow tool and an automatic clamping and centering device behind the main shaft;

and S72, performing full-automatic flaw detection on the closing quality of the end socket 3 and the opening 4 of the spinning forming piece C obtained in the step S6 by using a special curved surface ultrasonic automatic flaw detector, and detecting whether the position of the end socket 3 has machining defects such as orange peel and folding.

S8, grinding the inner surface of the curved surface, and grinding the inner surface defects of the end socket 3 found in the step S7 by adopting a special end socket 3 inner surface grinding machine tool according to the flaw detection result to obtain a spinning formed part C with qualified quality; the method specifically comprises the following steps:

s81, clamping a spinning formed part C by adopting a double-clamping-opening split type hollow tool and an automatic clamping and centering device behind the main shaft;

s82, automatically observing and judging the defect condition of the inner surface of the end socket 3 by using an automatic endoscope system of the special end socket 3 inner surface grinding machine tool, recording the corresponding position, and combining artificial confirmation;

and S83, grinding the defects of the inner surface of the end socket 3 found in the step S7 by adopting a numerical control automatic grinding mechanism of the special end socket 3 inner surface grinding machine tool to obtain a spinning formed part C with qualified quality, wherein the numerical control automatic grinding mechanism can be programmed and independently executed in the grinding process.

S9, performing heat treatment, namely performing T6 process treatment on the spinning forming piece C obtained in the step S8 to obtain a large-scale high-pressure storage and transportation gas cylinder liner blank; the method specifically comprises the following steps:

s91, clamping, namely clamping the spinning formed part C by 3-5 special split heat treatment tools at equal intervals to prevent the spinning formed part C from deforming during heat treatment; placing a plurality of spinning formed parts C on a three-dimensional heat treatment tool frame through a split type special heat treatment tool;

s92, quenching treatment, namely putting the spinning formed piece C clamped in the step S91 on a roller way of a horizontal continuous quenching and aging furnace, sending the spinning formed piece C into a quenching chamber for quenching treatment, heating the spinning formed piece C in the quenching chamber to 525 and 531 ℃ (for example, 525.5 ℃, 526 ℃, 526.5 ℃, 527 ℃, 527.5 ℃, 528 ℃, 528.5 ℃, 529 ℃, 529.5 ℃, 530 ℃, 530.5 ℃) and preserving heat for 2-4 hours (for example, 2.2 hours, 2.4 hours, 2.6 hours, 2.8 hours, 3 hours, 3.2 hours, 3.4 hours, 3.6 hours and 3.8 hours) in an environment of 525 and 531 ℃ (for example, 525.5 ℃, 526 ℃, 526.5 ℃, 527 ℃, 527.5 ℃, 528.5 ℃, 529 ℃, 529.5 ℃, 530 ℃ and 530.5 ℃), and then carrying out aqueous medium quenching on the spinning formed piece C;

s93, aging, transferring the quenched spinning formed piece C to an aging chamber for aging, and finally preserving the temperature for 6-10 hours (such as 6.3 hours, 6.6 hours, 7 hours, 7.3 hours, 7.7 hours, 8 hours, 8.4 hours, 8.7 hours, 9 hours, 9.3 hours and 9.7 hours) in the environment of 160-170 ℃ (such as 165 ℃, 170 ℃, 175 ℃, 180 ℃, 185 ℃, 190 ℃, 195 ℃ and 198 ℃) to prepare the large-scale high-pressure gas cylinder liner blank for storage and transportation. After being processed by the T6 process, the texture grain size of the liner blank at any position of the large-scale high-pressure storage and transportation gas cylinder is greater than or equal to the tensile strength of 345MPa, the yield strength of 310MPa and the elongation of 14 percent according to the standard of ASTME 112.

S10, processing a bottle opening 4, machining the inner diameter and the outer diameter of the bottle opening 4 of the large-scale high-pressure storage and transportation gas cylinder liner blank obtained in the step S9 by adopting a special ultra-long bottle opening 4 processing center, and processing internal threads of the bottle opening 4 to obtain a large-scale high-pressure storage and transportation gas cylinder liner; the method specifically comprises the following steps:

s101, clamping large-scale high-pressure gas cylinder inner container blanks by adopting 2-3 split self-clamping devices fixed on a machine tool workbench;

and S102, processing a bottle opening 4, namely performing high-speed processing on the outer diameter and the inner diameter of the bottle opening 4 and the inner thread of the bottle opening 4 of the large-sized high-pressure storage and transportation bottle liner blank obtained in the step S9 by adopting a special ultra-long bottle opening 4 processing center to obtain the large-sized high-pressure storage and transportation bottle liner, wherein the length of the bottle opening 4 is 40mm, the outer diameter of the bottle opening 4 is 50mm, and the inner diameter of the bottle opening 4 is 28 mm. In the embodiment of the invention, the inner diameter of the bottle mouth 4 is processed by a tailstock type power milling and boring device; the internal thread of the bottle mouth 4 is processed in a boring mode; the outer diameter of the bottle mouth 4 is processed by adopting a whirlwind milling mode.

S11, cleaning the inner container, namely cleaning the inner cavity of the large-scale high-pressure storage and transportation gas cylinder inner container obtained in the step S10 by high-pressure water spraying by adopting a special horizontal gas cylinder inner container cleaning machine to remove aluminum scraps and other processing pollutants; the method specifically comprises the following steps:

s111, horizontally placing the large high-pressure storage and transportation gas cylinder liner on a special horizontal gas cylinder liner cleaning machine, enabling a spraying mechanism of the special horizontal gas cylinder liner cleaning machine to enter the inner liner, and fixing the inner liner;

s112, cleaning the inner cavity of the large-scale high-pressure storage and transportation gas cylinder liner by adopting a high-pressure water spraying or ultrasonic cleaning mode to remove aluminum scraps and other processing pollutants;

s113, pouring water in an inclined angle of 45 degrees after cleaning;

and S114, drying the inner container by adopting an inward extending type steam dryer.

And S12, inspecting the finished product, namely inspecting the large-scale high-pressure storage and transportation gas cylinder liner obtained in the step S11 to obtain the finished product of the large-scale high-pressure storage and transportation gas cylinder liner.

And S13, performing carbon fiber winding on the finished product of the large high-pressure storage and transportation gas cylinder liner obtained in the step S12 to obtain an oversized high-pressure gas cylinder with one end sealed at the bottom 1, and detecting the limit pressure-bearing condition of the high-pressure gas cylinder.

The length of the large-scale high-pressure gas cylinder liner for storage and transportation prepared by the manufacturing method is 5-13m, the nominal outer diameter of the straight cylinder section 2 is phi 300-phi 850mm, the wall thickness of the straight cylinder section 2 is 3-10mm, and the integral straightness of the straight cylinder section 2 is not more than 0.5 mm/m; the tolerance of the wall thickness of the straight cylinder section 2 is less than or equal to +/-0.15 mm; the local straightness at any straight section position of the straight cylinder section 2 is not more than 0.5mm/300 mm; the roundness of any position of the straight cylinder section 2 is not more than 0.5 mm; the roughness of the inner surface of the straight cylinder section 2 is less than Ra1.6 μm, and the roughness of the outer surface of the straight cylinder section 2 is less than Ra3.2 μm. The volume of the large high-pressure storage and transportation gas cylinder liner prepared by the manufacturing method is far higher than that of the existing standard aluminum alloy liner, and the large high-pressure storage and transportation gas cylinder liner also has the characteristics of thin wall thickness, high pressure resistance, light weight and the like.

Example 1

The method for preparing the large-scale high-pressure storage and transportation gas cylinder liner with the diameter of 500mm, the length of 10m and the wall thickness of 6mm has the requirement of 25Mpa on the rated pressure of a high-pressure gas cylinder, and specifically comprises the following operation steps:

s1, integral reverse extrusion forming of blank with back cover 1

Selecting an aluminum ingot with the height of 1000mm and the diameter of 520mm as an extrusion blank, firstly heating the aluminum ingot to be extruded to 300 ℃, and simultaneously preheating an extrusion outer die and an extrusion inner rod to 300 ℃;

placing an aluminum ingot in an extrusion die, extruding the blank for 10 times to prepare a prefabricated pipe blank with a sealed bottom 1, and keeping the temperature of the die at 280 ℃ and 300 ℃ in the extrusion process;

machining the outer surface of the prefabricated blank by adopting a turning method; and (4) processing the inner surface of the prefabricated blank by adopting a boring method.

Thereby preparing a seamless pipe material consisting of a back cover 1 and a straight cylinder section 2 with an opening at one end, wherein the diameter of the back cover 1 of the seamless pipe material is phi 500mm, the thickness of the back cover 1 is uniformly and gradually thickened from 8mm at the edge to 12mm at the center of the back cover 1, the length of the straight cylinder section 2 is 1600mm, and the thickness of the straight cylinder section 2 is 38 mm.

S2, preparing the aluminum alloy inner container spinning tube, which comprises the following steps:

s21, performing pass tension three-wheel offset forward spinning on the seamless pipe manufactured in the step S1 by adopting a floating core die with the processing length of 2m, wherein the offset is set to be 6 mm;

in the spinning process of the step, traction force is adopted to pull the back cover 1 end of the seamless pipe, and the traction direction of the traction force is opposite to the flowing direction of the material; the traction force is constant force, and the traction speed is adaptive to the deformation speed of the material; the axial direction of the end of the back cover 1 is fixed on a traction mechanism to ensure the radial freedom of the end of the back cover 1; and the positioning device is adopted to fix and support the other end of the seamless pipe in the radial direction, so that the axial freedom of the other end of the seamless pipe is ensured.

Obtaining a spinning piece A; the dimensions of the spinning piece A are as follows: the length of the straight cylinder section 2 is 10.2mm, and the thickness of the straight cylinder section 2 is 6 mm.

S22, performing fixed-length processing on the spinning pipe of the aluminum alloy liner, namely performing fixed-length processing on the spinning piece A obtained in the step S21 by using an ultra-long double-head automatic sawing machine to obtain the spinning pipe of the aluminum alloy liner, wherein the length of the spinning pipe of the aluminum alloy liner is 10 m;

s23, cleaning the aluminum alloy inner container spinning tube, and cleaning the aluminum alloy inner container spinning tube obtained in the step S22 by adding a 40 ℃ neutral cleaning agent into a rotary spray cleaning machine or an ultrasonic cleaning machine; after cleaning, removing residual water stains on the surface by adopting an inward extending type drying device;

s3, grinding the inner surfaces of the back cover 1 and the straight cylinder section 2, and grinding the inner surface and the outer surface of the aluminum alloy liner spinning tube cleaned in the step S2 by using a numerical control inner and outer circle grinding machine; the method specifically comprises the following steps:

s51, clamping the aluminum alloy liner spinning tube by adopting a double-clamping-opening split type hollow tool and an automatic clamping and centering device behind the main shaft;

s52, carrying out flame spraying and heating on the spinning position to be closed of the spinning pipe of the aluminum alloy liner to 300 ℃ by adopting oxygen and propane/LNG combustion;

s53, performing 12-pass necking spinning on the aluminum alloy liner spinning tube by adopting a unilateral X-line, Z-line and rotary three-way interpolation type necking spinning machine to obtain a spinning forming piece B;

in the spinning process, the closing spinning band has 4 times of reverse spinning and is used for thickening 4 parts of the bottle mouth; the thickness of the end socket 3 of the prepared spinning forming part B is uniformly and gradually thickened from 8mm at the edge to 12mm at the position of the bottle mouth 4.

S6, processing a central hole of the bottle mouth 4, and clamping a spinning forming piece B by adopting 2 split type self-clamping devices fixed on a machine tool workbench; machining a center hole of the bottle opening 4 of the spinning forming piece B obtained in the step S5 by using a special ultra-long bottle opening 4 machining center to obtain a spinning forming piece C; ready for subsequent T6 processing;

s7, performing curved surface flaw detection, performing closing quality flaw detection on the spinning formed part C obtained in the step S6 by adopting a special curved surface ultrasonic automatic flaw detector, and detecting whether machining defects such as orange peel and folding exist at the position of the end socket 3; the method specifically comprises the following steps:

s91, clamping, namely clamping the spinning formed part C by adopting 4 special split heat treatment tools at equal intervals to prevent the spinning formed part C from deforming during heat treatment; placing a plurality of spinning formed parts C on a three-dimensional heat treatment tool frame through a split type special heat treatment tool;

s92, quenching, namely putting the spinning formed part C clamped in the step S91 on a roller way of a horizontal continuous quenching and aging furnace, sending the spinning formed part C into a quenching chamber for quenching, heating the spinning formed part C to 525-;

and S93, aging, namely transferring the quenched spinning formed part C to an aging chamber for aging, and finally preserving heat for 10 hours at the temperature of 170 ℃ to obtain the large-scale high-pressure gas cylinder liner blank for storage and transportation.

s101, clamping a large-scale high-pressure storage and transportation gas cylinder liner blank by adopting a split type hollow clamping tool;

and S102, processing a bottle opening 4, namely performing high-speed processing on the outer diameter and the inner diameter of the bottle opening 4 and the internal thread of the bottle opening 4 on the large-sized high-pressure storage and transportation bottle liner blank obtained in the step S9 by adopting a special bottle opening 4 processing center to obtain the large-sized high-pressure storage and transportation bottle liner, wherein the length of the bottle opening 4 is 40mm, the outer diameter of the bottle opening 4 is 50mm, and the inner diameter of the bottle opening 4 is 28 mm.

s113, pouring water in an inclined angle of 45 degrees after cleaning;

And S12, inspecting finished products, namely inspecting the large-scale high-pressure storage and transportation cylinder liner obtained in the step S11, performing sampling inspection on part of items, measuring the texture grain size of any six positions of the large-scale high-pressure storage and transportation cylinder liner subjected to sampling inspection, and respectively setting the texture grain size of the six positions to be 7, 6, 7, 6 and 5 according to the ASTME112 standard, and inspecting the tensile strength of the straight cylinder section 2 of the large-scale high-pressure storage and transportation cylinder liner subjected to sampling inspection. And (3) respectively measuring the yield strength and the elongation, wherein the tensile strength of the straight cylinder section 2 is 349MPa, the yield strength is 316MPa and the elongation is 14 percent, and the products produced in the batch are qualified to obtain the finished products of the large-scale high-pressure storage and transportation gas cylinder liner.

Through inspection, the texture grain size of any position of the large-scale high-pressure storage and transportation gas cylinder liner prepared by the embodiment is more than or equal to 5 levels according to the standard grade of ASTME112, the tensile strength of the straight cylinder section 2 is 349MPa, the yield strength is 316MPa, and the elongation is 14%; the testing limit pressure of the high-pressure gas cylinder obtained after the inner container is wound is 70MPa, and the requirement of the rated pressure of 25MPa is met.

Example 2

The method for preparing the large-scale high-pressure storage and transportation gas cylinder liner with the diameter of 780mm, the length of 12m and the wall thickness of 8mm has the requirement of the rated pressure of a high-pressure gas cylinder of 20MPa, and specifically comprises the following operation steps:

s1, integral reverse extrusion forming of blank with back cover 1

Selecting an aluminum ingot with the height of 1200mm and the diameter of 800mm as an extrusion blank, firstly heating the aluminum ingot to be extruded to 300 ℃, and simultaneously preheating an extrusion outer die and an extrusion inner rod to 300 ℃;

Thereby preparing a seamless pipe material consisting of a back cover 1 and a straight cylinder section 2 with one open end, wherein the diameter of the back cover 1 of the seamless pipe material is phi 780mm, the thickness of the back cover 1 is uniformly and gradually thickened from 10mm at the edge to 14mm at the center of the back cover 1, the length of the straight cylinder section 2 is 1600mm, and the thickness of the straight cylinder section 2 is 60 mm.

s21, performing 5-pass tension three-wheel offset forward spinning on the seamless pipe manufactured in the step S1 by adopting a floating core die with the processing length of 2m, wherein the offset is set to be 12 mm;

Obtaining a spinning piece A; the dimensions of the spinning piece A are as follows: the length of the straight cylinder section 2 is 12.2mm, and the thickness of the straight cylinder section 2 is 8 mm.

S22, performing fixed-length processing on the spinning pipe of the aluminum alloy liner, namely performing fixed-length processing on the spinning piece A obtained in the step S21 by using a double-head automatic sawing machine to obtain the spinning pipe of the aluminum alloy liner, wherein the length of the spinning pipe of the aluminum alloy liner is 12 m;

s3, grinding the inner surfaces of the back cover 1 and the straight cylinder section 2, and grinding the inner surface defects, the scratches and the damages of the inner and outer surfaces of the back cover 1 and the straight cylinder section 2 found in the step S3 by adopting a special overlong numerical control inner and outer circle grinding machine tool according to the flaw detection result; the method specifically comprises the following steps:

in the spinning process, the closing spinning band has 4 times of reverse spinning and is used for thickening 4 parts of the bottle mouth; the thickness of the seal head 3 of the prepared spinning forming piece B is uniformly and gradually thickened from 10mm of the edge to 14mm of the position of the bottle mouth 4.

s111, horizontally placing the large high-pressure storage and transportation gas cylinder liner on a special horizontal gas cylinder liner cleaning machine with a downward bottle opening 4, enabling a spraying mechanism of the special horizontal gas cylinder liner cleaning machine to enter the liner, and fixing the liner;

s113, pouring water in an inclined angle of 45 degrees after cleaning;

And S12, inspecting finished products, namely inspecting the large-scale high-pressure storage and transportation cylinder liner obtained in the step S11, performing sampling inspection on part of items, measuring the texture grain sizes of any six positions of the large-scale high-pressure storage and transportation cylinder liner subjected to sampling inspection, and respectively setting the texture grain sizes of the six positions to be 7-grade, 6-grade, 5-grade and 6-grade according to the ASTME112 standard, and inspecting the tensile strength of the straight cylinder section 2 of the large-scale high-pressure storage and transportation cylinder liner subjected to sampling inspection. And (3) respectively measuring the yield strength and the elongation, wherein the tensile strength of the straight cylinder section 2 is 345MPa, the yield strength is 310MPa and the elongation is 17 percent through measurement, and the products produced in the batch are qualified to obtain the finished products of the large-scale high-pressure storage and transportation gas cylinder liner.

Through inspection, the texture grain size of any position of the large-scale high-pressure storage and transportation gas cylinder liner prepared by the embodiment is more than or equal to 5 levels according to the standard grade of ASTME112, the tensile strength of the straight cylinder section 2 is 345MPa, the yield strength is 310MPa, and the elongation is 17%; the testing limit pressure of the high-pressure gas cylinder obtained after the inner container is wound is 73MPa, and the requirement of the rated pressure of 25MPa is met.

In conclusion, the manufacturing method of the large-scale high-pressure storage and transportation gas cylinder liner provided by the invention generally adopts a spinning processing method, so that the energy consumption is low, the pollution is small, the loss of raw materials in the whole manufacturing process is less, and the raw material cost is saved. The nominal outer diameter of the large-scale high-pressure storage and transportation gas cylinder liner processed by the manufacturing method is phi 300-phi 850mm, and the volume of the large-scale high-pressure storage and transportation gas cylinder liner is far higher than that of the existing standard aluminum alloy liner; the wall thickness of the straight cylinder section is 3-10mm, and the straight cylinder section has the characteristics of thin wall thickness and light weight; the tensile strength of the straight cylinder section is more than or equal to 345MPa, the yield strength is more than or equal to 310MPa, and the elongation is more than or equal to 14 percent; the grain size of the texture at any position of the straight cylinder section is more than or equal to 5 grades according to the standard of ASTME112, the texture of the material in the straight cylinder section is uniform and compact, the overall strength effect is excellent, and the straight cylinder section has high pressure resistance and has important significance for manufacturing high-pressure gas cylinders.

The above description is only exemplary of the invention and should not be taken as limiting the invention, as any modification, equivalent replacement, or improvement made within the spirit and principle of the invention is intended to be covered by the appended claims.

Claims

1. The manufacturing method of the large-scale high-pressure gas cylinder liner is characterized in that the large-scale high-pressure gas cylinder liner is an aluminum alloy liner with an integrated seamless structure, one end of the aluminum alloy liner is sealed, the other end of the aluminum alloy liner is closed to form a sealing head, and a bottle opening is formed in the aluminum alloy liner; the length of the large high-pressure storage and transportation gas cylinder liner is 5-13m, the nominal outer diameter of the straight cylinder section is phi 300-phi 850mm, and the rated pressure of the large high-pressure storage and transportation gas cylinder liner is 20-30 Mpa;

the wall thickness of the straight cylinder section is 3-10mm, and the integral straightness of the straight cylinder section is not more than 0.5 mm/m;

the tolerance of the wall thickness of the straight cylinder section is less than or equal to +/-0.15 mm;

the local straightness at any straight line section position of the straight cylinder section is not more than 0.5mm/300 mm;

the roundness of any position of the straight cylinder section is not more than 0.5 mm;

the roughness of the inner surface of the straight cylinder section is less than Ra1.6 mu m, and the roughness of the outer surface of the straight cylinder section is less than Ra3.2 mu m;

the structure type of the end enclosure is an ellipsoidal end enclosure, a disc-shaped end enclosure or a hemispherical end enclosure, the structure type of the bottom enclosure is the same as that of the end enclosure, the thickness of the end enclosure is uniformly and gradually thickened from the edge to the bottle opening, and the thickness of the bottom enclosure is uniformly and gradually thickened from the edge to the center of the bottom enclosure;

the thickness of the seal head is uniformly and gradually thickened from 5-8mm of the edge to 10-15mm of the bottle opening;

the thickness of the back cover is uniformly and gradually thickened from 5-8mm of the edge to 10-20mm of the center of the back cover;

the length of the bottle mouth is 40mm, the outer diameter of the bottle mouth is 50mm, and the inner diameter of the bottle mouth is 28 mm;

the manufacturing method of the large-scale high-pressure storage and transportation gas cylinder liner comprises the following steps:

the step S1 specifically includes the following steps:

the heating and back-extrusion equipment is a vertical extruder with extrusion force not less than 6000 tons; the extrusion outer die is provided with a back cover, and the length of the inner extrusion rod is 1.6-1.7 m;

the shape of the bottom sealing of the outer die is the same as that of the inner container of the large-scale high-pressure storage and transportation gas cylinder, but the allowance of 5-10mm is reserved in the thickness direction;

the type of the heating backward extrusion equipment is a numerical control oil press;

s2, preparing an aluminum alloy inner container spinning pipe;

the step S2 is: performing multi-pass tension external spinning forming treatment on the straight tube section of the seamless tube manufactured in the step S1 by using an overlong tube body tension spinning device to obtain an aluminum alloy inner container spinning tube; the method specifically comprises the following steps:

in the spinning manufacturing process of the spinning member A in the step S21, traction force is adopted to pull the bottom sealing end of the seamless pipe, and the traction direction of the traction force is opposite to the flowing direction of the material; the traction force is a constant force, and the traction speed is adaptive to the deformation speed of the material; the axial direction of the bottom sealing end is fixed on the traction mechanism, so that the radial freedom of the bottom sealing end is ensured; fixing and supporting the other end of the seamless pipe in the radial direction by adopting a positioning device, and ensuring the axial freedom of the other end of the seamless pipe;

s3, grinding the surfaces of the back cover and the straight cylinder section;

s4, performing flaw detection on the back cover and the straight cylinder section, performing ultrasonic flaw detection on the back cover and the straight cylinder section of the aluminum alloy liner spinning tube obtained in the step S3, and detecting the defects of air holes, inclusions, pits and microcracks on the inner surface;

s5, spinning and forming the end socket and the bottle mouth;

the step S5 is: spinning forming of the end socket and the bottle mouth is carried out on the opening of the aluminum alloy liner spinning tube by adopting a heating closing-up spinning machine, and a spinning forming piece B is obtained; the method specifically comprises the following steps:

s52, heating, namely heating the spinning part to be closed of the spinning pipe of the aluminum alloy liner to 380 ℃;

s53, forming and spinning the end socket and the bottle mouth, and performing multi-pass closing-up spinning on the aluminum alloy liner spinning tube heated in the step S42 by adopting a single-side X-line, Z-line and rotary three-way interpolation type closing-up spinning machine to obtain a spinning forming piece B; in the spinning process, the closing spinning has reverse spinning for the 1 st to 8 th times, and is used for thickening the bottle mouth part, and the thickness of the seal head of the prepared spinning forming piece B is uniformly and gradually thickened from 5mm to 8mm of the edge to 10mm to 15mm of the bottle mouth part;

the heating in the step S52 is carried out by adopting oxygen and propane/LNG for combustion flame heating;

s6, processing a central hole of the bottle mouth;

s7, curved surface flaw detection;

s8, grinding the inner surface of the curved surface;

and S11, cleaning the inner container.

2. The method for manufacturing the inner liner of the large-scale high-pressure storage and transportation gas cylinder according to claim 1, wherein in step S1a, the aluminum ingot is preheated by a heating furnace.

3. The method for manufacturing the inner container of the large-scale high-pressure storage and transportation gas cylinder according to claim 1, wherein in the step S1c and the step S1d, the size of the bottom sealing part is directly processed to the size required by the product.

4. The method for manufacturing the inner container of the large-scale high-pressure storage and transportation gas cylinder according to claim 1, wherein the heating in the steps S1b-S1d is performed by using oxygen and propane/LNG for combustion flame spraying heating.

5. The method for manufacturing the large-scale high-pressure storage and transportation gas cylinder liner according to claim 1, wherein the offset in the three-wheel offset forward spinning method in step S21 is set to be 6-12 mm.

6. The method for manufacturing the inner container of the large-scale high-pressure storage and transportation gas cylinder according to claim 1, wherein the cleaning machine in the step S23 is a rotary spray cleaning machine or an ultrasonic cleaning machine.

7. The method for manufacturing the large-scale high-pressure storage and transportation gas cylinder liner according to claim 1, wherein the cleaning of the aluminum alloy liner spinning tube with one end sealed is completed by heating a neutral cleaning agent at 30-45 ℃.

8. The method for manufacturing the inner container of the large-scale high-pressure storage and transportation gas cylinder according to claim 1, wherein the residual water stain on the surface is removed by adopting an inward-extending drying device after the aluminum alloy inner container spinning tube with one end being sealed.

9. The manufacturing method of the large-scale high-pressure storage and transportation gas cylinder liner as claimed in claim 1, characterized in that in the manufacturing method of the large-scale high-pressure storage and transportation gas cylinder liner:

and S9, performing heat treatment, namely performing T6 process treatment on the spinning formed part C obtained in the step S8 to obtain a large-scale high-pressure storage and transportation gas cylinder liner blank.

10. The method for manufacturing the inner container of the large-scale high-pressure storage and transportation gas cylinder according to claim 9, wherein the step S9 comprises the following steps:

s93, aging treatment, namely transferring the quenched spinning formed part C to an aging furnace for aging treatment, and finally preserving heat for 6-10 hours in an environment of 160-200 ℃ to obtain the large-scale high-pressure storage and transportation gas cylinder liner blank.

11. The method for manufacturing the large-scale high-pressure storage and transportation gas cylinder liner according to claim 10, wherein the quenching treatment and the aging treatment adopt a horizontal continuous quenching and aging furnace for heat treatment.