阅读说明：本技术 一种卫星复合气瓶封头及其制造方法 (Satellite composite gas cylinder end socket and manufacturing method thereof ) 是由 于斌 赵积鹏 马天驹 顾森东 刘志栋 张建军 张海 张涛 程彬 王祥龙 李玉峰 于 2021-08-27 设计创作，主要内容包括：本申请涉及复合材料气瓶技术领域,具体而言,涉及一种卫星复合气瓶封头及其制造方法,所述卫星复合气瓶封头,包括壳体以及接头,其中：壳体与接头通过电子束焊接；接头包括接头区和肩部补强区；壳体包括渐变过渡区、等壁厚薄膜区以及筒体区；肩部补强区与渐变过渡区平滑焊接,渐变过渡区与等壁厚薄膜区平滑渐变连接。本发明采用TA1纯钛、TA3钛合金两种材料,满足封头壳体塑性内衬低周疲劳寿命的较高断裂延伸率高塑性要求,同时满足封头接头刚性约束的高强度要求,解决了塑性内衬在气瓶疲劳循环中鼓包、断裂、屈曲、疲劳裂纹、渗透等破坏和失效等问题,具有超薄壁、轻重量、结构精度高、与复合层应变位移匹配性好、低周疲劳寿命高等优点。(The application relates to the technical field of composite gas cylinders, in particular to a satellite composite gas cylinder end socket and a manufacturing method thereof, wherein the satellite composite gas cylinder end socket comprises a shell and a connector, wherein: the shell and the joint are welded through electron beams; the joint comprises a joint area and a shoulder reinforcing area; the shell comprises a gradual transition area, an equal-wall-thickness film area and a barrel area; the shoulder reinforcing area is smoothly welded with the gradual transition area, and the gradual transition area is smoothly and gradually connected with the film area with the same wall thickness. The invention adopts two materials of TA1 pure titanium and TA3 titanium alloy, meets the requirements of higher fracture elongation and high plasticity of the low cycle fatigue life of the plastic lining of the shell of the seal head and the high strength requirement of rigid constraint of the joint of the seal head, solves the problems of damage and failure of the plastic lining in the fatigue cycle of the gas cylinder, such as bulging, fracture, buckling, fatigue crack, permeation and the like, and has the advantages of ultra-thin wall, light weight, high structural precision, good strain displacement matching with a composite layer, high low cycle fatigue life and the like.)

1. The utility model provides a compound gas cylinder head of satellite which characterized in that, includes casing and joint, wherein:

the shell and the joint are welded through electron beams;

the joint comprises a joint area and a shoulder reinforcing area;

the shell comprises a gradual transition area, an equal-wall-thickness film area and a barrel area;

the shoulder reinforcing area is smoothly welded with the gradual transition area, and the gradual transition area is smoothly and gradually connected with the equal-wall-thickness thin film area.

2. The satellite composite gas cylinder head of claim 1, wherein the material of the joint region and the shoulder reinforcement region is TA3 titanium alloy.

3. The satellite composite gas cylinder end socket according to claim 2, wherein the TA3 titanium alloy has a yield strength of 460MPa or more, a tensile strength of 540MPa or more, an elastic modulus of 107GPa or more, a plastic modulus of 1.3GPa or more, and a fracture elongation of 15 or more.

4. The satellite composite gas cylinder end socket according to claim 1, wherein the material of the gradual transition region, the equal-wall-thickness membrane region and the barrel region is TA1 pure titanium.

5. The satellite composite gas cylinder end socket according to claim 4, wherein the TA1 pure titanium has a yield strength of not less than 290MPa, a tensile strength of not less than 370MPa, an elastic modulus of not less than 105GPa, a plastic modulus of not less than 1.2GPa, and a breaking elongation of not less than 30%.

6. The satellite composite gas cylinder end socket according to claim 1, wherein the welding seam coefficient of the electron beam welding is more than or equal to 0.95.

7. The satellite composite gas cylinder end socket according to claim 1, wherein the outer curved surface rotation generatrix of the shell is an elliptic curve, and the inner curved surface rotation generatrix is a curve fitted with gradually-changing thickening coordinate points based on the outer curved surface.

8. The satellite composite gas cylinder end socket according to claim 1, wherein the equal-wall-thickness film area and the cylinder area have the same wall thickness, and the wall thickness is less than or equal to 1 mm.

9. The satellite composite gas cylinder end socket according to claim 8, wherein the roundness of the cylinder area is less than or equal to 1mm, the height of the cylinder area is greater than or equal to 10mm, and the flatness of the cylinder area is less than or equal to 1 mm.

10. A method for manufacturing a satellite composite gas cylinder head according to any one of claims 1-9, characterized by comprising the following steps:

step 1: manufacturing the seal head shell blank by adopting a TA1 pure titanium plate clamping plate hot stamping process and a turning process;

step 2: the manufacturing of the seal head joint blank is completed by adopting a TA3 titanium alloy bar turning process;

and step 3: connecting a TA1 pure titanium seal head shell blank and a TA3 titanium alloy seal head joint blank by adopting electron beam welding;

and 4, step 4: and (5) finishing the machining of the titanium alloy end socket by adopting a turning process.

Technical Field

The application relates to the technical field of composite gas cylinders, in particular to a satellite composite gas cylinder seal head and a manufacturing method thereof.

Background

The satellite propulsion subsystem, the fluid management system, the environment-friendly and life-saving system and the like all need pressure container products such as composite gas cylinders and the like, and the weight of the container products such as the composite gas cylinders, the propellant storage boxes and the like accounts for 50-80% of the total weight of the subsystem, so that the technical index requirements of the aerospace field on the weight of the pressure containers are very strict.

The composite gas cylinder with the lining having the long fatigue life and the thick wall is mainly adopted in the fields of common civil fields, aviation, ships, weapons and the like, when the gas cylinder works, the lining is in an elastic stress strain state, and the structural design is relatively simple. In the fields of satellites, airships, missiles and the like, the composite material gas cylinder can be designed into a low-cycle fatigue life, plastic working and ultrathin-wall lining composite material gas cylinder structure due to the disposable application characteristics of the composite material gas cylinder.

Aiming at an ultra-thin wall lining composite gas cylinder, when the gas cylinder works, a lining is in a plastic stress strain state, in the fatigue circulation of the gas cylinder, the lining has a large uneven plastic strain behavior, especially the spiral fiber at a seal head is wound and accumulated, and the continuous reaming and winding leads to the change of a winding angle and the change of winding tension, so that the stress strain behavior of the lining seal head is very complex, and the lining is extremely easy to damage and lose efficacy due to the inconsistent strain displacement of the lining and a composite layer in the pressurizing and pressure releasing processes of the gas cylinder, and the problems of bulging, fracture, buckling, fatigue crack, permeation and the like of the lining are solved. The lining consists of a sealing head and a cylinder body, and the lining cylinder body belongs to the elastic-plastic stress strain behavior of a uniform film area, so the structural design and the manufacture of the sealing head are the main difficulties and key technologies for the development of the gas cylinder.

Disclosure of Invention

The application mainly aims to provide a satellite composite gas cylinder end socket and a manufacturing method thereof, and solves the problems of structural design and manufacturing of a dissimilar material ultrathin wall end socket which works in a plastic stress strain state and meets the requirements of low-cycle fatigue life.

In order to realize above-mentioned purpose, this application provides a compound gas cylinder head of satellite, includes casing and joint, wherein: the shell and the joint are welded through electron beams; the joint comprises a joint area and a shoulder reinforcing area; the shell comprises a gradual transition area, an equal-wall-thickness film area and a barrel area; the shoulder reinforcing area is smoothly welded with the gradual transition area, and the gradual transition area is smoothly and gradually connected with the film area with the same wall thickness.

Further, the material of the joint area and the shoulder reinforcing area is TA3 titanium alloy.

Furthermore, the yield strength of the TA3 titanium alloy is more than or equal to 460MPa, the tensile strength is more than or equal to 540MPa, the elastic modulus is more than or equal to 107GPa, the plastic modulus is more than or equal to 1.3GPa, and the elongation at break is more than or equal to 15%.

Furthermore, the material of the gradual transition region, the equal-wall-thickness film region and the barrel region is TA1 pure titanium.

Furthermore, the yield strength of TA1 pure titanium is more than or equal to 290MPa, the tensile strength is more than or equal to 370MPa, the elastic modulus is more than or equal to 105GPa, the plastic modulus is more than or equal to 1.2GPa, and the elongation at break is more than or equal to 30%.

Furthermore, the welding seam coefficient of the electron beam welding is more than or equal to 0.95.

Furthermore, the outer curved surface rotating generatrix of the shell is an elliptic curve, and the inner curved surface rotating generatrix is a curve fitted by gradually-changed thickening coordinate points with the outer curved surface as the reference.

Furthermore, the wall thickness of the film area with the same wall thickness as that of the cylinder area is not more than 1 mm.

Furthermore, the roundness of the cylinder area is less than or equal to 1mm, the height of the cylinder area is more than or equal to 10mm, and the planeness of the cylinder area is less than or equal to 1 mm.

In addition, the invention also provides a method for manufacturing the satellite composite gas cylinder end socket, which comprises the following steps: step 1: manufacturing the seal head shell blank by adopting a TA1 pure titanium plate clamping plate hot stamping process and a turning process; step 2: the manufacturing of the seal head joint blank is completed by adopting a TA3 titanium alloy bar turning process; and step 3: connecting a TA1 pure titanium seal head shell blank and a TA3 titanium alloy seal head joint blank by adopting electron beam welding; and 4, step 4: and (5) finishing the machining of the titanium alloy end socket by adopting a turning process.

The satellite composite gas cylinder end socket and the manufacturing method thereof provided by the invention have the following beneficial effects:

1. the invention adopts two materials of TA1 pure titanium and TA3 titanium alloy, meets the requirements of higher fracture elongation and high plasticity of the low cycle fatigue life of the plastic lining of the shell of the seal head and the high strength requirement of rigid constraint of the joint of the seal head, solves the problems of damage and failure of the plastic lining in the fatigue cycle of the gas cylinder, such as bulging, fracture, buckling, fatigue crack, permeation and the like, and has the advantages of ultra-thin wall, light weight, high structural precision, good strain displacement matching with a composite layer, high low cycle fatigue life and the like.

2. The gradual transition area of the invention adopts the design of smooth gradual transition of thickness and curvature, solves the problem of the compatibility of strain displacement between the lining end socket shell and the composite layer caused by the winding accumulation of the root part of the end socket joint, the change of a reaming winding angle and the change of winding tension, and solves the problem of the stress concentration of a welding seam at the junction of the end socket and the shell by adopting the design of the end socket shell with a barrel section. The seal head equal-wall-thickness film area and the cylinder area adopt ultrathin equal-wall-thickness design, and the requirements of light weight and high performance factor of the satellite gas cylinder are met.

3. The invention adopts the technical scheme that the seal head joint blank and the seal head shell blank are welded firstly and then machined, and solves the problem that the requirements on the dimensional tolerance and the geometric tolerance of the seal head are strict.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, serve to provide a further understanding of the application and to enable other features, objects, and advantages of the application to be more apparent. The drawings and their description illustrate the embodiments of the invention and do not limit it. In the drawings:

fig. 1 is a schematic view of a satellite composite gas cylinder head provided according to an embodiment of the application;

in the figure: 1-shell, 11-gradual transition region, 12-equal wall thickness film region, 13-barrel region, 2-joint, 21-joint region and 22-shoulder reinforcing region.

Detailed Description

In order to make the technical solutions better understood by those skilled in the art, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only partial embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

As shown in fig. 1, the present application provides a satellite composite gas cylinder head, including casing 1 and joint 2, wherein: the shell 1 and the joint 2 are welded through electron beams; the joint 2 comprises a joint area 21 and a shoulder reinforcing area 22; the shell 1 comprises a gradual transition area 11, an equal-wall-thickness film area 12 and a barrel area 13; the shoulder reinforcing area 22 is smoothly welded with the gradual transition area 11, and the gradual transition area 11 is smoothly and gradually connected with the equal-wall-thickness thin film area 12.

Specifically, the composite gas cylinder for the satellite requires light weight, high strength, high reliability and high safety, the gas cylinder performance factor is defined as the maximum pressure and volume multiplied by the net weight, and the technical requirement of the satellite gas cylinder performance factor is generally more than 30km, so the gas cylinder needs to adopt an ultrathin wall plastic working metal lining high-strength carbon fiber winding composite gas cylinder structure, the lining design adopts the maximum weight reduction principle, the lining end socket and the wall thickness of the cylinder shell are thinned to the maximum extent, the weight is the lightest, and the highest performance factor design requirement can be met. The liner sealing head shell area needs to meet stress strain coordination with a composite layer, the liner shell belongs to low-cycle fatigue life design, and according to the coefficient-Manson low-cycle fatigue cycle theory, the higher the elongation rate of the material is, the higher the low-cycle fatigue life is, so that a high-elongation low-strength metal material is selected in the shell area. The joint area of the lining end socket needs to meet the rigid fixation constraint condition of the gas cylinder, the dynamic load condition of the composite gas cylinder is severe, and a metal material with high yield strength and low elongation rate needs to be adopted. The ultra-thin wall lining winding technology has high requirements on the dimensional tolerance and the form and position tolerance of the lining, the traditional process of machining before welding and welding after welding cannot meet the requirement on the structural precision of the shell, the junction of the end socket and the barrel has not only film stress, but also complex stress states such as bending stress and the like, the junction of the traditional end socket and the barrel is welded, the stress concentration of a welding line can be caused, and the winding area of the end socket joint needs to adopt a structural reinforcement design because the fiber exertion coefficient is low. Therefore, according to the design requirements, the embodiment of the invention provides a satellite composite gas cylinder end socket, which integrally adopts a design mode that a connector 2 and a shell 1 are provided with cylinder sections, and mainly comprises the shell 1 and the connector 2, wherein the connector 2 and the shell 1 adopt electron beam butt welding seams, so that the problem of concentrated stress of the welding seams at the junction of the end socket and a cylinder is solved, the connector 2 comprises a connector area 21 and a shoulder reinforcing area 22, the connector area 21 is mainly used for butt joint with other devices, such as a wire hanging table, a radial constraint cylinder, a thread sealing surface, an air outlet pipe and the like, the shoulder reinforcing area 22 is calculated according to actual reinforcing coefficients, and the high-strength requirement of rigid constraint of the end socket is mainly met. The shell 1 mainly comprises a gradual transition area 11, an equal-wall-thickness film area 12 and a barrel area 13, the wall thickness of a shoulder reinforcing area 22 and the gradual transition area 11 and the smooth transition welding of curvature between inner surfaces are realized, the wall thickness of the equal-wall-thickness film area 12 in the gradual transition area 11 is gradually thickened to the designed thickness, the wall thickness is smoothly and gradually changed, the wall thickness of the integral gradual transition area 11 and the curvature of the inner surface are not suddenly changed, and the problem of strain displacement coordination of the lining seal shell and a composite layer caused by seal head root winding accumulation, reaming winding angle change and winding tension change is solved through the smooth gradual transition design.

Further, the material of the joint region 21 and the shoulder reinforcing region 22 is TA3 titanium alloy. The TA3 titanium alloy has the advantages of moderate yield strength and hardness, strong abrasion resistance, certain abrasion resistance when used as the contact surfaces of a sealing surface, an external thread and the like of a gas port metal sealing ball head, good weldability of the TA3 titanium alloy and the TA1 titanium alloy, and high strength of a welding joint, so that the TA3 titanium alloy is adopted.

Furthermore, the yield strength of the TA3 titanium alloy is more than or equal to 460MPa, the tensile strength is more than or equal to 540MPa, the elastic modulus is more than or equal to 107GPa, the plastic modulus is more than or equal to 1.3GPa, and the elongation at break is more than or equal to 15%. The parameters of the TA3 titanium alloy are selected according to actual design conditions.

Further, the material of the gradual transition region 11, the equal-thickness film region 12 and the barrel region 13 is TA1 pure titanium. The pure titanium TA1 has the advantages of 30% elongation at break, and the low cycle fatigue life of the plastic lining is proportional to the elongation at break according to the low cycle fatigue property of the material, so that the TA1 titanium alloy can obtain higher low cycle fatigue life.

Furthermore, the yield strength of TA1 pure titanium is more than or equal to 290MPa, the tensile strength is more than or equal to 370MPa, the elastic modulus is more than or equal to 105GPa, the plastic modulus is more than or equal to 1.2GPa, and the elongation at break is more than or equal to 30%. The parameters of TA1 pure titanium are selected according to actual design conditions.

Specifically, the TA1 material is adopted as the end enclosure shell, the high fracture elongation performance of the TA1 material is exerted, the TA3 material is adopted as the joint material, the higher strength and hardness performance of the TA3 titanium alloy are exerted, the TA3 titanium alloy and the TA3 titanium alloy are connected in a welding mode, the welding performance of the two titanium alloys is better, therefore, the dissimilar metal structure is adopted to meet the dual requirements, the TA1 titanium alloy is adopted alone, the hardness requirement of the joint is not met, the TA3 titanium alloy is adopted alone, the low-cycle fatigue performance requirement of the shell cannot be met, and therefore, the special technical requirement of the plastic lining can be guaranteed only by adopting the dissimilar metal structure.

Furthermore, the welding seam coefficient of the electron beam welding is more than or equal to 0.95. Preventing the weld stress from being excessively concentrated.

Further, the outer curved surface rotation generatrix of the shell 1 is an elliptic curve, and the inner curved surface rotation generatrix is a curve fitted with gradually-changed thickening coordinate points based on the outer curved surface. An elliptic curve or an equal tension curve can be selected according to actual conditions by the rotating bus of the outer curved surface of the shell 1, the appearance streamline of the composite gas cylinder end socket is attractive, curve fitting is carried out by taking the outer curved surface as a reference by the inner curved surface, the wall thickness of the shell 1 is ensured to be ultrathin, the wall thickness is equal, and the weight of the composite gas cylinder is greatly reduced.

Furthermore, the wall thickness of the film area 12 with the same wall thickness as that of the cylinder area 13 is equal to or less than 1 mm. The equal-wall-thickness film area 12 and the cylinder area 13 adopt the design of ultrathin equal wall thickness, and mainly meet the requirements of light weight and high performance factor of the satellite composite gas cylinder.

Furthermore, the roundness of the cylinder area 13 is less than or equal to 1mm, the height of the cylinder area 13 is more than or equal to 10mm, and the planeness of the cylinder area 13 is less than or equal to 1 mm. The parameters of barrel region 13 are selected according to the actual design.

In addition, the invention also provides a method for manufacturing the satellite composite gas cylinder end socket, which comprises the following steps: step 1: manufacturing a seal head shell 1 blank by adopting a TA1 pure titanium plate clamping plate hot stamping process and a turning process; step 2: the manufacturing of the seal head joint 2 blank is completed by adopting a TA3 titanium alloy bar turning process; and step 3: connecting a TA1 pure titanium seal head shell 1 blank and a TA3 titanium alloy seal head joint 2 blank by adopting electron beam welding; and 4, step 4: and (5) finishing the machining of the titanium alloy end socket by adopting a turning process.

The method for manufacturing the satellite composite gas cylinder end socket provided by the embodiment of the invention adopts a technical scheme that the end socket joint 2 blank and the end socket shell 1 blank are welded firstly and then machined, so that the problem that the requirements on the size tolerance and the form and position tolerance of the end socket are strict is solved.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.