CN109668051B

CN109668051B - Large-scale ultrahigh-pressure gas cylinder liner and manufacturing method thereof

Info

Publication number: CN109668051B
Application number: CN201811601578.7A
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: 2020-08-07
Anticipated expiration: 2038-12-26
Also published as: CN109668051A

Abstract

The invention provides a large-scale ultrahigh-pressure gas cylinder liner and a manufacturing method thereof, wherein the large-scale ultrahigh-pressure gas cylinder liner is an aluminum alloy liner with an integrated seamless structure, one end of which is sealed, the other end of which is closed to form a sealing head and a bottle opening, and comprises a straight cylinder section, the sealing head and the sealing head which are respectively positioned at two ends of the straight cylinder section, and the bottle opening is positioned on the sealing head; the length of the aluminum alloy inner container is 5-13m, the nominal external diameter of the straight cylinder section is phi 300-phi 850mm, and the rated pressure of the ultrahigh-pressure gas cylinder is 35-70 Mpa. The invention adopts the plate blank as the raw material, generally adopts a spinning method, has no welding line on the product, simple preparation process, convenient operation, low energy consumption and little pollution, has less loss of raw materials in the manufacturing process and saves the cost of the raw materials. The aluminum alloy inner container processed by the manufacturing method has the characteristics of overlarge size, high reliability, thin wall and light weight; the internal material has uniform and compact structure, excellent overall strength effect and ultrahigh pressure resistance.

Description

Large-scale ultrahigh-pressure gas cylinder liner and manufacturing method thereof

Technical Field

The invention belongs to the technical field of high-pressure containers, and particularly relates to an inner container of a large ultrahigh-pressure gas cylinder and a manufacturing method thereof.

Background

With the rapid development and industrialization of hydrogen fuel cells and electric vehicles, research and construction of hydrogen source technology and hydrogen energy infrastructure have attracted high attention in developed countries. The safe and economic hydrogen storage and transportation technology is the key point for pushing the hydrogen energy utilization to the practicability and industrialization. The most common and direct way of storing hydrogen is to use a super-high pressure gas cylinder with 35-70MPa of pressure to store hydrogen under high pressure. The high-pressure hydrogen storage can be used at normal temperature, the hydrogen can be directly released through the adjustment of the valve, and the high-pressure hydrogen storage cylinder has the advantages of simple structure, less energy consumption for preparing compressed hydrogen, high filling speed and the like, and becomes a main mode of hydrogen energy storage and transportation at the present stage. The storage and transportation of 35-70MP ultrahigh pressure gas cylinders and the use of compressed hydrogen gas are the main means for transporting these gases from main pipelines to gas consumption sites, gas filling stations, etc.

At present, the aluminum alloy liner carbon fiber fully-wound ultrahigh-pressure gas cylinder has numerous advantages, and the aluminum alloy liner high-pressure composite hydrogen cylinder has the following advantages:

(1) the gas cylinder has light weight, good rigidity and high strength, the thickness of the material is only 50% -70% of that of the steel cylinder under the same performance, and the density is lower, so the weight of the gas cylinder is only 35% -40% of that of the traditional steel cylinder;

(2) the fatigue failure of the metal material is usually sudden failure without obvious warning, and the combination of a reinforcement in the composite material and a matrix can effectively transfer load and prevent the expansion of cracks, so that the fracture toughness of the gas cylinder is improved;

(3) when a large number of reinforcing fibers in the composite material cause the material to be overloaded and a few fibers to be broken, the load can be quickly redistributed to the fibers which are not damaged, so that the whole gas cylinder cannot lose the bearing capacity in a short time;

(4) when the composite material gas cylinder is damaged by impact or high-speed impact, dangerous fragments cannot be generated, so that the injury to personnel is reduced or avoided;

(5) the requirement of corrosion resistance can be met without special treatment;

(6) 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;

(7) the fiber winding provides a convenient and reliable technical scheme for ultrahigh pressure, and is the most effective scheme for realizing 70MPa ultrahigh pressure hydrogen storage.

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 large-scale hydrogen transportation tank vehicles, gas filling station gas cylinders, transport ship gas cylinders and the like.

However, limited by material production and technical capability, the carbon fiber fully-wound ultrahigh-pressure 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, hydrogen and industrial high-purity gas tank cars and further master key technologies and products of storage and transportation devices such as large compressed natural gas, hydrogen and mixed gas with independent property rights, the development of large ultrahigh-pressure gas cylinder liner products with 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 ultrahigh-pressure gas cylinder and a manufacturing method thereof. At least solves the problems of small volume, overweight and poor reliability of the prior ultrahigh-pressure gas cylinder.

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

a large ultrahigh-pressure 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 is formed in the aluminum alloy liner; the length of the large ultrahigh-pressure 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 ultrahigh-pressure gas cylinder is 35-70 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 0.3 mm/m;

preferably, the tolerance of the wall thickness of the straight cylinder section is less than or equal to +/-0.1 mm;

preferably, the local straightness at any straight section position of the straight cylinder section is not more than 0.3mm/300 mm;

still preferably, the whole straightness of the straight cylinder section is not more than 2 mm/full length;

still preferably, the roundness of any position of the straight cylinder section is not more than 0.3 mm;

still preferably, the roughness of the inner surface of the straight cylinder section is less than Ra0.8 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;

still 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.

The manufacturing method of the large ultrahigh-pressure gas cylinder liner preferably comprises the following steps:

s1, integrally carrying out reverse extrusion forming on the blank with the back cover;

s2, preparing an aluminum alloy inner container spinning pipe;

s3, inspecting and repairing the defects of the aluminum alloy liner cyclone tube, performing visual automatic comparison inspection on the back cover and the straight tube section of the aluminum alloy liner cyclone tube prepared in the step S2 for defects, and repairing the inspected repairable defects;

s4, spinning and forming the end socket and the bottle mouth;

s5, processing a central hole of the bottle mouth;

s6, curved surface flaw detection;

s7, grinding the inner surface of the curved surface;

s8, heat treatment;

s9, cleaning the inner container;

s10, inspecting the finished product, namely inspecting the ultrahigh-pressure gas cylinder liner obtained in the step S9 to obtain the finished product of the ultrahigh-pressure gas cylinder liner;

s11, coating, namely coating a bonding agent on the outer surface of the ultrahigh-pressure gas cylinder liner obtained in the step S10 to obtain an aluminum alloy liner coated piece;

and S12, winding carbon fibers on the aluminum alloy inner container coating piece obtained in the step S11, and after the winding is finished, precisely processing the inner diameter and the outer diameter of the bottle mouth, the inner threads of the bottle mouth and the outer threads of the bottle mouth.

In the method for manufacturing the inner liner of the large ultra-high pressure gas cylinder, preferably, in step S1: adopting a heating backward extrusion process combined with turning and boring processes to prepare a seamless pipe consisting of a back cover and a straight cylinder section with an opening at one end; the method specifically comprises 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 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 temperature preservation;

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

s1e, processing the inner surface of the prefabricated pipe blank to the size required by spinning the blank by a boring method to obtain a seamless pipe consisting of a back cover and a straight cylinder section with an opening at one end;

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

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

still preferably, the machining surface roughness of the bottom sealing part and the inner surface of the straight cylinder section in the steps S1d-S1e is not higher than Ra1.6;

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

In the manufacturing method of the inner container of the large-scale ultrahigh-pressure gas cylinder, preferably, the heating and back-extruding equipment is a vertical extruder with the 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 ultrahigh-pressure 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 above method for manufacturing an inner container of a large ultra-high pressure gas cylinder, preferably, step S2 includes: 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, processing the spinning piece A obtained in the step S21 in a fixed length mode to obtain the aluminum alloy inner container spinning pipe;

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

still preferably, the ultra-long 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 inner container of the large ultrahigh-pressure gas cylinder, preferably, in the spinning manufacturing process of the spinning member 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 above method for manufacturing an inner container of a large ultra-high pressure gas cylinder, preferably, step S4 includes: 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:

s41, 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;

s42, heating, namely heating the spinning part to be closed of the spinning pipe of the aluminum alloy liner to 180 DEG and 390 ℃;

s43, 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 S42 is combustion flame heating using oxygen, propane/L NG.

Preferably, in the method for manufacturing an inner container of a large ultra-high pressure gas cylinder, the method comprises the following steps:

s5, 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 S4 by a machine to obtain a spinning formed piece C;

s6, performing curved surface flaw detection, performing closing quality flaw detection on the spinning formed part C obtained in the step S5, and detecting whether the position of a seal head has machining defects of orange peel and folding;

s7, grinding the inner surface of the curved surface, and grinding the defects of the inner surface of the end socket found in the step S6 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;

s8, performing heat treatment, namely performing T6 process treatment on the spinning forming piece C obtained in the step S7 to obtain the ultrahigh-pressure gas cylinder liner;

s9, cleaning the inner container, and performing high-pressure water spraying cleaning on the inner cavity of the ultrahigh-pressure gas cylinder inner container obtained in the step S8 by using a horizontal gas cylinder inner container cleaning machine to remove processing pollutants;

wherein, preferably, the step S8 includes the following steps:

s81, clamping, namely clamping the spinning formed part C obtained in the step S7 by 3-5 special split heat treatment tools at equal intervals;

s82, quenching, namely putting the spinning formed part C clamped in the step S81 into a quenching furnace for quenching, heating the spinning formed part C to 525-;

s83, 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 ultrahigh-pressure gas cylinder liner;

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 ultrahigh-pressure gas cylinder liner provided by the invention adopts a spinning processing method, has high product processing precision, no welding seam on the whole and strict surface quality control, and meets the requirements of the ultrahigh-pressure gas cylinder liner. And the preparation process is simple, the operation is convenient, the energy consumption is low, the pollution is small, the loss of raw materials in the whole preparation process is less, and the raw material cost is saved. The nominal outer diameter of the large-scale ultrahigh-pressure gas cylinder liner processed by the manufacturing method is phi 300-phi 850mm, and the volume and the bearable pressure after winding are both far higher than those of the existing standard aluminum alloy liner; the length is 5-13m, the wall thickness of the straight cylinder section is 3-10mm, and the straight cylinder 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. In the prior art, the ultrahigh-pressure gas cylinder liner with the length dimension larger than 5 meters is difficult to produce, the processing method of the invention carries out automatic visual inspection and repair on surface defects of the prepared semi-finished product, ensures that the surface of any position of the prepared aluminum alloy liner is not scratched with the depth larger than 0.03mm, the finish degree of the inner surface reaches Ra0.8 mu m, and has important significance for bearing the aluminum alloy gas cylinder.

Drawings

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

FIG. 2 is a flow chart of a method for manufacturing the inner container of the large-scale ultrahigh-pressure 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 ultrahigh-pressure gas cylinder liner, which is formed by processing a round or square plate blank by using the manufacturing method; as shown in fig. 1, the ultra-high pressure gas cylinder liner is an aluminum alloy liner with an integrated seamless structure, wherein one end of the aluminum alloy liner is sealed by a back cover 1, the other end of the aluminum alloy liner is sealed by a formed end socket 3 and a bottle opening 4, the aluminum alloy liner comprises the back cover 1, a straight cylinder section 2, the end socket 3 and the bottle opening 4, the back cover 1 and the end socket 3 are respectively arranged at two ends of the straight cylinder section 2, and the bottle opening 4 is arranged on the end. 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 large ultrahigh-pressure gas cylinder liner 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, 12.5m), the nominal outer diameter of the straight cylinder section 2 is 300-phi 850mm (such as phi 350mm, phi 400mm, phi 450mm, phi 500mm, phi 550mm, phi 600mm, phi 650mm, phi 700mm, phi 750mm, 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, 9.5mm), and the whole straightness of the straight cylinder section 2 is not more than 3.0 mm/m; the tolerance of the wall thickness of the straight cylinder section 2 is less than or equal to +/-0.1 mm; the local straightness at any straight section position of the straight cylinder section 2 is not more than 0.3mm/300 mm; the roundness of any position of the straight cylinder section 2 is not more than 0.3 mm; the roughness of the inner surface of the straight cylinder section 2 is less than Ra0.8 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 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 15-20mm (such as 15.5mm, 16mm, 16.5mm, 17mm, 17.5mm, 18.mm, 18.5mm, 19mm and 19.5mm) of the center of the back cover 1; the rated pressure of the ultrahigh-pressure gas cylinder is 35-70MPa (such as 37MPa, 40MPa, 43MPa, 47MPa, 50MPa, 53MPa, 56MPa, 60MPa, 63MPa, and 67 MPa).

As shown in fig. 2, an embodiment of the present invention further provides a method for manufacturing an inner container of a large ultra-high pressure gas cylinder, including 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 mold, namely preheating the outer extrusion mold and the inner extrusion rod to 400 ℃ (for example, 220 ℃, 240 ℃, 260 ℃, 280 ℃, 300 ℃, 320 ℃, 340 ℃, 360 ℃ and 380 ℃) in a mode of carrying out combustion flame heating by adopting oxygen and propane/L NG;

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 back cover 1, the length of the extrusion outer die is about 1.5m, the shape of the back cover 1 of the extrusion outer die is the same as that of the back cover 1 of the ultrahigh-pressure gas cylinder liner, 5-10mm (such as 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, 9mm and 9.5mm) of allowance is reserved in the thickness direction, and after extrusion, the allowance is removed by adopting a turning process, so that the external shape and size of the back cover 1 part reach the external size of the product back cover 1; 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 die 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 die is not changed during spinning, and the offset in the three-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; after cleaning, removing residual water stains on the surface by adopting an inward extending type drying device;

and S24, performing flaw detection on the aluminum alloy inner container spinning tube, performing full-automatic flaw detection on the bottom sealing 1 and the straight cylinder section 2 of the aluminum alloy inner container spinning tube obtained in the step S23 by adopting a special curved surface ultrasonic automatic flaw detector, and detecting whether machining defects such as peeling, wrinkles, cracks and the like exist.

S3, defect inspection and repair are carried out on the aluminum alloy liner spin-pressure pipe, visual automatic comparison inspection of defects is carried out on the back cover 1 and the straight cylinder section 2 of the aluminum alloy liner spin-pressure pipe obtained in the step S2, and the inspected defects are repaired; the method specifically comprises the following steps:

s31, detecting defects of the back cover 1 and the straight cylinder section 2, installing a vision inspection system at the front end of the inner circle coping mechanism, programming and detecting the back cover 1 and the straight cylinder section 2 of the aluminum alloy liner spinning tube obtained in the step S2, detecting scratches and collisions with the depth of the inner surface of the back cover 1 and the straight cylinder section 2 larger than 0.03mm, and simultaneously detecting defects such as air holes, inclusions, pits, microcracks and the like;

s32, removing the vision detection system, and automatically repairing the repairable defects detected in the step S31 by adopting an automatic inner circle grinding machine tool through the conversion of positioning coordinates according to the detection result; the method specifically comprises the following steps:

s321, grinding the outer surface of the aluminum alloy inner container spinning tube by using a cloth abrasive belt;

s322, roughly grinding the inner surface of the aluminum alloy inner container spinning tube by using a millennium grinding wheel;

and S323, carrying out fine grinding on the inner surface of the aluminum alloy inner container spinning tube by using a scouring pad wheel.

S4, 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:

s42, 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/L NG combustion;

s43, 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 S42 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;

s5, 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 S4 by using a special ultra-long bottle opening 4 machining center to obtain a spinning forming piece C; ready for subsequent T6 processing;

s6, performing curved surface flaw detection, performing closing quality flaw detection on the spinning formed part C obtained in the step S5 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:

s61, 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 S62, 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 S5 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.

S7, grinding the inner surface of the curved surface, and grinding the inner surface defects of the end socket 3 found in the step S6 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:

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;

s872, automatically observing and judging the defect condition of the inner surface of the seal head 3 by adopting an automatic endoscope system arranged on the special seal head 3 inner surface grinding machine tool, recording the corresponding position, and combining artificial confirmation;

and S73, grinding the defects of the inner surface of the end socket 3 found in the step S6 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.

S8, performing heat treatment, namely performing T6 process treatment on the spinning forming piece C obtained in the step S7 to obtain the ultrahigh-pressure gas cylinder liner; the method specifically comprises the following steps:

s81, 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;

s82, quenching treatment, namely putting the spinning formed piece C clamped in the step S81 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;

s83, aging treatment, transferring the quenched spinning formed piece C to an aging chamber for aging treatment, and finally preserving heat 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 an environment of 160-200 ℃ (such as 165 ℃, 170 ℃, 175 ℃, 180 ℃, 185 ℃, 190 ℃, 195 ℃ and 198 ℃) to prepare the ultrahigh-pressure gas cylinder liner.

S9, cleaning the inner container, namely performing high-pressure water spraying cleaning on the inner cavity of the inner container of the ultrahigh-pressure gas cylinder obtained in the step S8 by using a special horizontal gas cylinder inner container cleaning machine to remove aluminum scraps and other processing pollutants; the method specifically comprises the following steps:

s91, horizontally placing the ultrahigh-pressure 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 liner, and fixing the liner;

s92, cleaning the inner cavity of the ultrahigh-pressure gas cylinder liner by adopting a high-pressure water spraying or ultrasonic cleaning mode to remove aluminum scraps and other processing pollutants;

s93, pouring water in an inclined angle of 45 degrees after the cleaning is finished;

and S94, drying the liner by adopting an inward extending type steam dryer.

And S10, inspecting the finished product, namely inspecting the ultrahigh-pressure gas cylinder liner obtained in the step S9 to obtain the finished product of the ultrahigh-pressure gas cylinder liner.

And S11, coating, namely coating a bonding agent on the outer surface of the ultrahigh-pressure gas cylinder liner obtained in the step S10 to obtain an aluminum alloy liner coating piece so as to improve the bonding degree between the aluminum alloy and the resin and the fibers to be wound.

S12, carbon fiber winding is carried out on the aluminum alloy inner container coating piece obtained in the step S11, precision machining of the inner diameter and the outer diameter of the bottle opening 4 and the inner thread and the outer thread is carried out after the winding is finished, so that the molded surface of the bottle opening 4 is prevented from being oxidized and damaged in the heat treatment process and other processes, the machined surface meets the requirements of ultrahigh precision and finish degree, the requirement for hydrogen micromolecule ultrahigh sealing is met, the ultrahigh-pressure gas bottle with one end sealed at the bottom 1 is obtained, the limit pressure-bearing condition of the ultrahigh-pressure gas bottle is detected, the length of the bottle opening 4 is 40mm, the outer diameter of the bottle opening 4 is 50mm, and the inner.

The length of the ultrahigh-pressure gas cylinder liner 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 ultrahigh-pressure gas cylinder liner prepared by the manufacturing method is far higher than that of the existing standard aluminum alloy liner, and the ultrahigh-pressure gas cylinder liner also has the characteristics of thin wall thickness, high pressure resistance, light weight and the like.

Example 1

The method comprises the following steps of preparing an oversized ultrahigh-pressure gas cylinder liner with a diameter of 500mm, a length of 10m and a wall thickness of 6mm, wherein the rated pressure of a high-pressure gas cylinder is required to be 50 Mpa:

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;

processing the outer surface of the prefabricated pipe blank by adopting a turning method; and (4) processing the inner surface of the prefabricated pipe 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 4-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, 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. Thereby obtaining a spinning piece A; the dimensions of the spinning piece A are as follows: the length of the straight cylinder section 2 is 10.2m, 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;

s41, 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;

s42, 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/L NG combustion;

s43, 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.

S5, 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 S4 by using a special ultra-long bottle opening 4 machining center to obtain a spinning forming piece C; ready for subsequent T6 processing;

s72, 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;

s81, 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;

s82, quenching, namely putting the spinning formed part C clamped in the step S81 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 S83, aging, 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 ultrahigh-pressure gas cylinder liner.

and S94, drying the liner by adopting an inward extending type steam dryer.

And S10, inspecting the finished product, namely inspecting the ultrahigh-pressure gas cylinder liner obtained in the step S9, performing sampling inspection on part of items, measuring the texture grain sizes of any six positions of the ultrahigh-pressure gas cylinder liner subjected to sampling inspection, and respectively setting the texture grain sizes of the six positions to be 7-grade, 6-grade, 7-grade, 6-grade and 6-grade according to the ASTME112 standard according to the measurement result, and inspecting the tensile strength of the straight cylinder section 2 of the ultrahigh-pressure gas cylinder liner subjected to sampling inspection. And (3) respectively measuring the yield strength and the elongation rate, wherein the tensile strength of the straight cylinder section 2 is 349MPa, the yield strength is 310MPa, and the elongation rate is 17%, and the products produced in the batch are qualified to obtain the finished product of the ultrahigh-pressure gas cylinder liner.

Through inspection, the texture grain size of any position of the liner of the ultrahigh-pressure gas cylinder prepared by the embodiment is more than or equal to 6 levels according to the standard grade of ASTM E112, and the straight cylinder section 2 has the tensile strength of 349MPa, the yield strength of 310MPa and the elongation of 17%; the testing limit pressure of the high-pressure gas cylinder obtained after the inner container is wound is 135Mpa, and the requirement of 50Mpa of rated pressure is met.

Example 2

The method is characterized by preparing an oversized ultrahigh-pressure gas cylinder liner with a diameter of 780mm, a length of 12m and a wall thickness of 8mm, wherein the rated pressure of a high-pressure gas cylinder is required to be 50Mpa, and the method 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 350 ℃, and simultaneously preheating an extrusion outer die and an extrusion inner rod to 350 ℃;

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 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; in the spinning process, 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. Thereby obtaining a spinning piece A; the dimensions of the spinning piece A are as follows: the length of the straight cylinder section 2 is 12.2m, 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 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 12 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 35 ℃ 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;

s542, carrying out flame spraying and heating on a spinning position to be closed of the spinning pipe of the aluminum alloy liner to 300 ℃ by adopting oxygen and propane/L NG combustion;

s543, carrying out 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, thereby obtaining 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 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.

and S83, aging, transferring the quenched spinning formed part C to an aging chamber for aging, and finally, preserving heat for 8 hours in an environment of 190 ℃ to obtain the ultrahigh-pressure gas cylinder liner.

and S94, drying the liner by adopting an inward extending type steam dryer.

And S10, inspecting the finished product, namely inspecting the ultrahigh-pressure gas cylinder liner obtained in the step S9, performing sampling inspection on part of items, measuring the texture grain sizes of any six positions of the ultrahigh-pressure gas cylinder liner subjected to sampling inspection, and respectively setting the texture grain sizes of the six positions to be 7-grade, 6-grade and 7-grade according to the ASTME112 standard, and inspecting the tensile strength of the straight cylinder section 2 of the ultrahigh-pressure gas 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 323MPa and the elongation is 14 percent through measurement, and the products produced in the batch are qualified to obtain the finished product of the ultrahigh-pressure gas cylinder liner.

Through inspection, the texture grain size of any position of the liner of the ultrahigh-pressure gas cylinder prepared by the embodiment is more than or equal to 6 levels according to the standard grade of ASTM E112, the tensile strength of the straight cylinder section 2 is 345MPa, the yield strength is 323MPa, and the elongation is 14%; the testing limit pressure of the high-pressure gas cylinder obtained after the inner container is wound is 130Mpa, and the requirement of 50Mpa of rated pressure is met.

In conclusion, the manufacturing method of the large ultrahigh-pressure 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 ultrahigh-pressure gas cylinder liner processed by the manufacturing method is phi 300-phi 850mm, and the volume and the bearable pressure of the large-scale ultrahigh-pressure gas cylinder liner are far higher than those 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 grade 6 according to the ASTME112 standard, 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 ultrahigh 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 ultrahigh-pressure gas cylinder liner is characterized in that the ultrahigh-pressure 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 bottom seal, a straight cylinder section, a seal head and a bottle opening, the bottom seal 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 large ultrahigh-pressure 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 ultrahigh-pressure gas cylinder liner is 35-70 Mpa;

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 roughness of the inner surface of the straight cylinder section is less than Ra0.8 mu m, and the roughness of the outer surface of the straight cylinder section is less than Ra3.2 mu m;

the wall thickness of the straight cylinder section is 3-10mm, and the integral straightness of the straight cylinder section is not more than 0.3 mm/m;

the tolerance of the wall thickness of the straight cylinder section is less than or equal to +/-0.1 mm;

the local straightness at any straight line section position of the straight cylinder section is not more than 0.3mm/300 mm;

the integral straightness of the straight cylinder section is not more than 2 mm/full length;

the roundness of any position of the straight cylinder section is not more than 0.3 mm;

the manufacturing method of the ultrahigh-pressure gas cylinder liner comprises the following steps:

the step S1: adopting a heating backward extrusion process combined with turning and boring processes to prepare a seamless pipe consisting of a back cover and a straight cylinder section with an opening at one end; the method specifically comprises the following steps:

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:

the offset in the tension three-wheel offset forward spinning method in the step S21 is set to be 6-12 mm;

the ultra-long cleaning machine in the step S23 is a rotary spray cleaning machine or an ultrasonic cleaning machine;

cleaning the aluminum alloy inner container spinning pipe with one end sealed by adopting a neutral cleaning agent heated to 30-45 ℃;

cleaning the aluminum alloy inner container spinning tube with one end sealed, and then removing residual water stains on the surface by adopting an inward-extending drying device;

performing 3-5 times of spinning process on the straight tube section of the seamless tube manufactured by the S1 by using an overlong tube body tension spinning device and a tension three-spinning wheel staggered pitch forward spinning method to obtain a spinning part A; in the spinning process, 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; during spinning, a floating core mould with the length of 1-2m is adopted for spinning auxiliary processing;

the offset in the tension three-wheel offset forward spinning method is set to be 6-12 mm;

the total deformation of the seamless pipe subjected to spinning treatment is 55-70%;

in the spinning manufacturing process of the spinning part A, 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;

s4, spinning and forming the end socket and the bottle mouth;

the step S4 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:

s43, forming and spinning the end socket and the bottle mouth, and performing 10-18-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 1 st to 8 th steps of closing spinning are provided with reverse spinning for thickening the bottle mouth part;

s5, processing a central hole of the bottle mouth;

s6, curved surface flaw detection;

s7, grinding the inner surface of the curved surface;

s8, heat treatment;

s9, cleaning the inner container;

2. The method for manufacturing the inner container of the large-scale ultrahigh-pressure 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 ultrahigh-pressure gas cylinder according to claim 2, wherein in the step S1c and the step S1d, 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 ultrahigh-pressure gas cylinder according to claim 3, wherein the surface roughness of the inner surfaces of the bottom sealing part and the straight cylinder section in the steps S1d-S1e is not higher than Ra1.6.

5. The method for manufacturing the inner container of the large ultrahigh-pressure gas cylinder according to claim 1, wherein the heating in the steps S1b-S1d adopts oxygen and propane/L NG for combustion flame heating.

6. The manufacturing method of the inner container of the large-scale ultrahigh-pressure gas cylinder as claimed in claim 1, wherein the heating and back-extruding device is a vertical extruder with an extrusion force of 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.

7. The manufacturing method of the large ultrahigh-pressure gas cylinder liner as claimed in claim 6, wherein the shape of the back cover of the outer mold is the same as that of the ultrahigh-pressure gas cylinder liner, and a margin of 5-10mm is reserved in the thickness direction.

8. The method for manufacturing the inner container of the large-scale ultrahigh-pressure gas cylinder according to claim 7, wherein the type of the heating and back-extruding equipment is a numerical control oil press.

9. The method for manufacturing the inner container of the large-scale ultrahigh-pressure gas cylinder according to claim 1, wherein the heating in the step S42 is performed by using oxygen and propane/L NG for combustion flame heating.

10. The manufacturing method of the large-scale ultrahigh-pressure gas cylinder liner according to claim 1, characterized in that in the manufacturing method of the large-scale ultrahigh-pressure gas cylinder liner:

and S9, cleaning the inner container, and performing high-pressure water spraying cleaning on the inner cavity of the ultrahigh-pressure gas cylinder inner container obtained in the step S8 by using a horizontal gas cylinder inner container cleaning machine to remove processing pollutants.

11. The method for manufacturing the inner container of the large-scale ultrahigh-pressure gas cylinder according to claim 10, wherein the step S8 comprises the following steps:

s83, aging, transferring the quenched spinning formed piece C to an aging furnace for aging, and finally preserving heat for 6-10 hours in an environment of 160-200 ℃ to obtain the ultrahigh-pressure gas cylinder liner.

12. The method for manufacturing the large-scale ultrahigh-pressure gas cylinder liner according to claim 11, wherein the quenching treatment and the aging treatment are carried out by heat treatment in a horizontal continuous quenching and aging furnace.