Fuel tank and airplane

Abstract

The invention provides an oil tank and an airplane, and relates to the technical field of general aviation. The oil tank comprises a shell, first mortises and second mortises are formed in the two ends of the shell respectively, the first mortises are evenly formed in the edge of one end of the shell, and the second mortises are evenly formed in the edge of the other end of the shell; the first head plate is provided with a first tenon matched with the first mortise; the first head plate is provided with a first tenon matched with the first mortise, the second head plate is provided with a second tenon matched with the second mortise, and the first tenon and the second tenon can be bent, so that the shell, the first head plate and the second head plate are fixed under the condition that the first tenon is embedded into the first mortise and the second tenon is embedded into the second mortise, and a sealed cavity is defined by the first head plate, the second head plate and the shell. The fuel tank provided by the invention is particularly suitable for fuel storage of an airplane, can meet the strict technical requirements of the airplane on the air tightness, the oil tightness and the pressure resistance of the fuel tank, and meanwhile, realizes low-cost and high-efficiency production and manufacturing.

Description

Technical Field

[0001] This application relates to the field of general aviation technology, and more specifically, to a fuel tank and an aircraft. Background Technology

[0002] In the field of general aviation aircraft manufacturing, fuel tanks are core components that ensure the aircraft's range. Their structural strength, sealing performance, and manufacturing cost directly affect the aircraft's safety and economy. Currently, the production process of aircraft fuel tanks generally adopts the traditional model of "aluminum alloy sheet stamping + plug welding". The specific process is as follows: first, a special stamping mold is designed according to the specifications of the fuel tank shell and partitions. The aluminum alloy sheet is processed into the shell and partitions of the preset shape using stamping equipment. Then, the stamped parts are assembled and welded together using a plug welding process.

[0003] However, the aforementioned traditional processes have significant drawbacks and are difficult to meet the industry's demands for cost control and quality stability: High production costs and long cycles: Different specifications of fuel tanks require the design and manufacture of exclusive stamping molds. Mold development costs are high and the mold manufacturing cycle is long, resulting in extremely high cost-sharing pressure when producing small batches of multi-specification fuel tanks, while also extending the product development and delivery cycle. Unstable welding quality and poor sealing and pressure resistance: During plug welding, the assembly gap between the partition and the shell is difficult to control precisely, and fluctuations in weld parameters (such as current and speed) can easily lead to welding defects. Common defects include porosity (formed by gas not escaping in time) and incomplete fusion (the weld metal is not fully fused with the base material). These defects directly damage the sealing structure of the fuel tank, resulting in substandard airtightness and oil tightness. Some serious defects can also reduce the overall strength of the fuel tank, making its pressure resistance unable to meet the pressure environment requirements of aircraft flight (such as structural stability under high-altitude low-pressure environments). Poor process adaptability: For fuel tanks of different volumes and sizes, stamping dies need to be redesigned, making it impossible to achieve "one process to adapt to multiple specifications". This results in insufficient production line flexibility and difficulty in quickly responding to market demands for adjustments to fuel tank specifications.

[0004] In summary, the existing aircraft fuel tank manufacturing process suffers from the pain points of "high cost, low quality, and weak adaptability," and there is an urgent need for a new process and corresponding fuel tank structure that can reduce mold investment, improve welding quality, and adapt to multiple fuel tank specifications. Summary of the Invention

[0005] To address at least one of the aforementioned problems, this application proposes a fuel tank and an aircraft, specifically applicable to aircraft fuel storage, which can meet the stringent technical requirements of aircraft for fuel tank airtightness, oil tightness, and pressure resistance, while achieving low-cost and high-efficiency manufacturing.

[0006] According to a first aspect of this application, at least one embodiment of this application provides an oil tank, comprising: a shell, wherein a first mortise and a second mortise are respectively provided at both ends of the shell, the first mortise being evenly distributed along the edge of one end of the shell, and the second mortise being evenly distributed along the edge of the other end of the shell; a first head plate, provided with a first tenon adapted to the first mortise, the first tenon being used to embed into the first mortise to mechanically connect the shell and the first head plate; and a second head plate, provided with a second tenon adapted to the second mortise, the second tenon being used to embed into the second mortise to mechanically connect the shell and the second head plate, wherein the first tenon and the second tenon are bendable to fix the shell, the first head plate, and the second head plate when the first tenon is embedded in the first mortise and the second tenon is embedded in the second mortise, thereby forming a sealed cavity by the first head plate, the second head plate, and the shell.

[0007] For example, in some embodiments of this application, a third tenon is provided in the middle of the housing, and the third tenon is evenly distributed on the inner wall of the middle of the housing. The oil tank further includes a partition plate with a tenon adapted to the third tenon. The third tenon is used to embed into the third tenon so that the housing and the partition plate are mechanically connected. The third tenon can be bent so that the housing and the partition plate are fixed when the third tenon is embedded in the third tenon.

[0008] For example, in some embodiments of this application, the first tenon, the second tenon, the third tenon, the first mortise, the second mortise, and the third mortise are respectively formed by CNC laser cutting.

[0009] For example, in some embodiments of this application, the mortise and tenon joints between the housing and the first head plate, the second head plate and the partition are respectively welded by gas metal arc welding.

[0010] For example, in some embodiments of this application, the housing, the first head plate, the second head plate, and the partition are made of aluminum sheet.

[0011] For example, in some embodiments of this application, the sealed cavity meets the requirements of air tightness test, compressed air oil tightness test, pressure resistance test, and oil leakage test.

[0012] For example, in some embodiments of this application, when the first tenon is embedded in the first mortise, the second tenon is embedded in the second mortise, and the third tenon is embedded in the third mortise, the width of the first tenon and the length of the first mortise, the width of the second tenon and the length of the second mortise, and the width of the third tenon and the length of the third mortise respectively conform to a first fit tolerance, and the length of the first tenon and the depth of the first mortise, the length of the second tenon and the depth of the second mortise, and the length of the third tenon and the depth of the third mortise respectively conform to a second fit tolerance.

[0013] For example, in some embodiments of this application, the first head plate, the second head plate, and the partition plate are respectively provided with oil inlets to realize the injection, replenishment, or discharge of oil in the oil tank.

[0014] For example, in some embodiments of this application, a sealing element is further included, disposed at the oil inlet, for sealing the oil inlet after oil filling or discharge is completed.

[0015] According to a second aspect of this application, at least one embodiment of this application provides an aircraft, including: a fuel tank as described in any one of the first aspects, for storing fuel required for flight of the aircraft and supplying fuel to the aircraft's power system to provide fuel supply support for the power system.

[0016] Through the above exemplary embodiments, in view of the problems of "high stamping die cost, numerous welding defects, and poor specification adaptability" in the existing aircraft fuel tank manufacturing process, the fuel tank and aircraft provided in this application have at least one of the following beneficial effects: Significantly reduced costs: The elimination of traditional stamping molds reduces mold investment costs to zero; the use of CNC laser cutting to process mortise and tenon structures eliminates the trimming process after stamping, shortening the production cycle for a single batch, with particularly prominent cost advantages for small-batch, multi-specification production; Significantly improved welding quality and sealing performance: The mortise and tenon joint is first fixed in the assembly position by a mechanical structure to ensure the joint gap, and then combined with continuous gas metal arc welding to effectively reduce defects such as porosity and lack of fusion; after multiple rounds of air tightness, oil tightness and pressure resistance tests, the product qualification rate has been improved, meeting the stringent requirements of aircraft for fuel tank sealing and strength; Highly adaptable to specifications and flexible in process: For oil tanks of different volumes and sizes, only minor adjustments to the size or spacing of the tenon / mortise are needed (no need to re-open the mold). The CNC laser cutting machine can quickly switch processing parameters to achieve "one set of processes covering all specifications", thus improving the response speed of the production line. Higher structural stability and safety: The independent sealed oil chambers formed by the partition can prevent overall fuel leakage in the event of local damage, thus improving the safety of aircraft flight; the combination of mortise and tenon structure and continuous welds enhances the overall impact resistance of the fuel tank, making it suitable for complex pressure environments at high altitudes.

[0017] It should be understood that the above general description and the following detailed description are merely exemplary and do not limit this application. Attached Figure Description

[0018] The above and other objects, features, and advantages of this application will become more apparent from the detailed description of exemplary embodiments with reference to the accompanying drawings. The drawings described below are merely some embodiments of this application and are not intended to limit the scope of this application.

[0019] Figure 1 A schematic diagram of an oil tank showing a plug-welded assembly structure of a conventional stamped part in the prior art; Figure 2 A schematic diagram of a conventionally stamped partition is shown. Figure 3 This application provides a schematic diagram of a fuel tank with a mortise and tenon welded assembly structure. Figure 4 This diagram shows a partition plate manufactured by CNC laser cutting, as provided in this application. Detailed Implementation

[0020] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided so that this application will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar parts, and therefore repeated descriptions of them will be omitted.

[0021] The described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Numerous specific details are provided in the following description to give a full understanding of embodiments of this disclosure. However, those skilled in the art will recognize that the technical solutions of this disclosure can be practiced without one or more of these specific details, or other methods, components, materials, devices, etc. In these cases, well-known structures, methods, devices, implementations, materials, or operations will not be shown or described in detail.

[0022] The flowcharts shown in the accompanying drawings are merely illustrative and do not necessarily include all content and operations / steps, nor do they necessarily have to be performed in the described order. For example, some operations / steps can be broken down, while others can be combined or partially combined; therefore, the actual execution order may change depending on the specific circumstances.

[0023] The terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or apparatuses.

[0024] Those skilled in the art will understand that the accompanying drawings are merely schematic diagrams of exemplary embodiments, and the modules or processes in the drawings are not necessarily essential for implementing this application, and therefore cannot be used to limit the scope of protection of this application.

[0025] Figure 1 A schematic diagram of an oil tank showing a conventional stamped part with plug-welded assembly structure in the prior art.

[0026] like Figure 1 As shown, in the traditional stamped parts plug-welded assembly structure of the oil tank, after the shell and the partition are joined, intermittent plug welding is performed through the plug welding hole. The weld is a scattered flat fillet weld, which has the problem of uneven assembly gap.

[0027] like Figure 2 As shown, the surface of the conventionally stamped partition is provided with circular plug welding holes for plug welding, and there are burrs left over from stamping at the edges.

[0028] Figure 3 A schematic diagram of the fuel tank with a mortise and tenon welding assembly structure provided in this application is shown.

[0029] like Figure 3 As shown, the fuel tank includes: a shell 101, a first head plate 102, and a second head plate 103. The components are assembled and welded together using a mortise and tenon structure.

[0030] The shell 101 has a first tenon and a second tenon at its two ends, respectively. The first tenon is evenly distributed on the edge of one end of the shell, and the second tenon is evenly distributed on the edge of the other end of the shell.

[0031] The first head plate 102 is provided with a first tenon that is adapted to the first mortise groove. The first tenon is used to insert into the first mortise groove so that the housing 101 and the first head plate 102 can be mechanically connected.

[0032] The second head plate 103 is provided with a second tenon that is adapted to the second mortise. The second tenon is used to fit into the second mortise so that the housing 101 and the second head plate 103 can be mechanically connected.

[0033] The first tenon and the second tenon can be bent so that, when the first tenon is inserted into the first mortise and the second tenon is inserted into the second mortise, the housing 101, the first head plate 102, and the second head plate 103 are fixed, thereby forming a sealed cavity by the first head plate 102, the second head plate 103, and the housing 101.

[0034] The sealed cavity meets the requirements for air tightness test, compressed air oil tightness test, pressure resistance test, and oil leakage test.

[0035] For example, air tightness test: inflation pressure 15~20KPa, pressure held for at least 15 minutes without pressure drop; Oil leakage test: After injecting more than 80% of the rated oil volume, there is no oil leakage after standing for 24 hours; Air compressor oil tightness test: After injecting more than 80% of the rated oil volume, inflate to 15~20KPa, and maintain pressure for at least 15 minutes without leakage; Pressure resistance test: Inflate to a pressure ≥39.7KPa, maintain pressure for at least 5 minutes without pressure drop or cavity damage.

[0036] This application uses only this as an example for the various test parameters of the sealed cavity of the fuel tank, but the test parameters are not limited to this.

[0037] According to the example embodiment, a third tenon is provided in the middle of the housing 101, and the third tenon is evenly distributed on the inner wall of the middle of the housing 101. The fuel tank also includes a partition 104.

[0038] The partition 104 is provided with a tenon that fits into the third mortise. The third tenon is used to insert into the third mortise so that the housing 101 and the partition 104 are mechanically connected. The third tenon can be bent so that the housing 101 and the partition 104 are fixed when the third tenon is inserted into the third mortise.

[0039] According to some embodiments, the housing 101, the first head plate 102, the second head plate 103, and the partition 104 are all made of aluminum sheet and are CNC laser-cut to form the first tenon, the second tenon, the third tenon, the first mortise, the second mortise, and the third mortise, eliminating the traditional stamping and trimming process. Figure 4 As shown, the partition processed by CNC laser cutting in this application has tenons evenly distributed on the edges, no burrs, and the tenon dimensions meet the tolerance.

[0040] The mortise and tenon joints between the shell 101 and the first head plate 102, the second head plate 103 and the partition plate 104 are respectively welded by gas metal arc welding.

[0041] According to some embodiments, the welding parameters are: welding current of 180-200A and welding speed of 5-8mm / s, suitable for mortise and tenon joint welding requirements. After welding, all welds undergo 100% visual inspection and penetrant testing to check for defects such as surface cracks and internal lack of fusion. If defects are found, they are repaired and then re-inspected.

[0042] According to the example embodiment, when the first tenon is embedded in the first mortise, the second tenon is embedded in the second mortise, and the third tenon is embedded in the third mortise, the width of the first tenon and the length of the first mortise, the width of the second tenon and the length of the second mortise, and the width of the third tenon and the length of the third mortise respectively meet the first fit tolerance, and the length of the first tenon and the depth of the first mortise, the length of the second tenon and the depth of the second mortise, and the length of the third tenon and the depth of the third mortise respectively meet the second fit tolerance.

[0043] According to some embodiments, both the first fit tolerance and the second fit tolerance are H7 / g6 fit tolerances. This application uses this as an example only, but is not limited thereto.

[0044] According to an example embodiment, the fuel tank also includes an oil inlet 105 and a seal (not shown in the figure).

[0045] The first head plate 102, the second head plate 103, and the partition plate 104 are respectively provided with oil inlets 105 to realize the injection, replenishment, or discharge of oil in the oil tank.

[0046] The seal is located at the oil inlet 105 and is used to seal the oil inlet 105 after the oil is added or drained, so as to prevent oil leakage from the sealed cavity and external impurities from entering the sealed cavity.

[0047] According to some embodiments, the seal is made of rubber or metal.

[0048] This application also provides an aircraft, including a fuel tank as described above, which is installed in a pre-designated fuel tank in the wing or fuselage of the aircraft for storing fuel required for flight. The fuel tank is connected to the aircraft's fuel filling system via a fuel filler port and to the aircraft's power system (such as an engine) via a fuel pipeline, providing continuous fuel supply support to the power system and ensuring the aircraft's normal flight endurance.

[0049] Furthermore, for different aircraft specifications (or different fuel requirements of the same aircraft model), this application can achieve adaptation by finely adjusting the tenon and groove spacing of the fuel tank (within the range of 10-30mm) or the tenon size (keeping the H7 / g6 tolerance). There is no need to redesign and manufacture molds; only the processing parameters of the CNC laser cutting machine need to be adjusted to complete the production of fuel tanks of different specifications.

[0050] This application provides a fuel tank and aircraft that eliminates the traditional stamping mold, thus reducing mold investment costs to zero. Simultaneously, it utilizes CNC laser cutting to process the mortise and tenon structure, eliminating the need for post-stamping trimming and effectively shortening the production cycle for a single batch. This cost advantage is particularly prominent in small-batch, multi-specification production scenarios. Furthermore, the mortise and tenon joint is first precisely fixed in position by a mechanical structure, ensuring a stable joint gap. Combined with continuous metal arc welding (GMAW), this effectively reduces welding defects such as porosity and incomplete fusion. Multiple rounds of airtightness, oiltightness, and pressure resistance tests have verified a significantly improved product qualification rate, fully meeting the aircraft's requirements for fuel tank sealing performance and structure. The system meets stringent strength requirements. For fuel tanks of varying volumes and sizes, only minor adjustments to the size or spacing of the tenons / mortises are needed for adaptation, eliminating the need to redesign and manufacture molds. CNC laser cutting machines can quickly switch processing parameters, truly achieving "one process covering all specifications," significantly improving production line response speed. Furthermore, the system offers enhanced structural stability and safety. Independent sealed oil chambers formed by partitions prevent overall fuel leakage in the event of localized damage to the tank, further improving aircraft flight safety. The tight integration of the mortise and tenon structure with continuous welds also enhances the overall impact resistance of the fuel tank, perfectly adapting to the complex pressure environment at high altitudes.

[0051] The aircraft fuel tank and manufacturing process provided in this application can be directly applied to the mass production of aircraft, and can also be adapted to the fuel tank requirements of other aircraft models by fine-tuning the tenon / mortise parameters. Its core processes (CNC laser cutting mortise and tenon, continuous metal arc welding) are mature and controllable, and the equipment used (laser cutting machine, welding machine) are all standard industry equipment, requiring no special customization, and can be quickly implemented and promoted on existing production lines.

[0052] Furthermore, the fuel tank structure of this application meets the stringent requirements of the aviation industry for sealing, strength, and safety. Actual trial production has verified that the product has a high qualification rate, low cost, and strong adaptability, and has significant industrial application value and market promotion prospects.

[0053] It should be clearly understood that this application describes how specific examples are formed and used, but this application is not limited to any details of these examples. Rather, based on the teachings of the disclosure of this application, these principles can be applied to many other embodiments.

[0054] Furthermore, it should be noted that the above figures are merely illustrative representations of the processes included in the method according to exemplary embodiments of this application, and are not intended to be limiting. It is readily understood that the processes shown in the above figures do not indicate or limit the temporal order of these processes. Additionally, it is readily understood that these processes may be executed synchronously or asynchronously, for example, in multiple modules.

[0055] Exemplary embodiments of this application have been specifically shown and described above. It should be understood that this application is not limited to the detailed structures, arrangements, or implementation methods described herein; rather, this application is intended to cover various modifications and equivalent arrangements that fall within the objectives and scope of the appended claims.

Claims

1. A fuel tank, characterized in that, include: The housing has a first tenon and a second tenon at its two ends, the first tenon being evenly distributed along the edge of one end of the housing, and the second tenon being evenly distributed along the edge of the other end of the housing. The first head plate is provided with a first tenon that is adapted to the first mortise groove. The first tenon is used to fit into the first mortise groove so that the housing and the first head plate can be mechanically connected. The second head plate is provided with a second tenon that is adapted to the second mortise. The second tenon is used to embed into the second mortise so that the housing and the second head plate can be mechanically connected. The first tenon and the second tenon can be bent so that when the first tenon is embedded in the first mortise and the second tenon is embedded in the second mortise, the housing, the first head plate, and the second head plate are fixed, thereby forming a sealed cavity by the first head plate, the second head plate, and the housing.

2. The fuel tank as described in claim 1, characterized in that, A third tenon is provided in the middle of the housing, and the third tenon is evenly distributed on the inner wall of the middle part of the housing. The oil tank also includes: The partition is provided with a tenon that fits into the third mortise. The third tenon is used to insert into the third mortise so that the housing and the partition can be mechanically connected. The third tenon can be bent so that the housing and the partition can be fixed when the third tenon is inserted into the third mortise.

3. The fuel tank as described in claim 2, characterized in that, The first tenon, the second tenon, the third tenon, the first mortise, the second mortise, and the third mortise are all formed by CNC laser cutting.

4. The fuel tank as described in claim 2, characterized in that, The mortise and tenon joints between the shell and the first head plate, the second head plate, and the partition are respectively welded using gas metal arc welding.

5. The fuel tank as described in claim 2, characterized in that, The shell, the first head plate, the second head plate, and the partition are made of aluminum sheet.

6. The fuel tank as described in claim 1, characterized in that, The sealed cavity meets the requirements for air tightness test, compressed air oil tightness test, pressure resistance test, and oil leakage test.

7. The fuel tank as described in claim 2, characterized in that, When the first tenon is embedded in the first mortise, the second tenon is embedded in the second mortise, and the third tenon is embedded in the third mortise, the width of the first tenon and the length of the first mortise, the width of the second tenon and the length of the second mortise, and the width of the third tenon and the length of the third mortise respectively meet the first fit tolerance, and the length of the first tenon and the depth of the first mortise, the length of the second tenon and the depth of the second mortise, and the length of the third tenon and the depth of the third mortise respectively meet the second fit tolerance.

8. The fuel tank as described in claim 2, characterized in that, The first head plate, the second head plate, and the partition plate are each provided with an oil inlet to enable the injection, replenishment, or discharge of oil in the oil tank.

9. The fuel tank as described in claim 8, characterized in that, Also includes: A sealing element, disposed at the oil inlet, is used to seal the oil inlet after oil filling or discharge is completed.

10. An aircraft, characterized in that, include: The fuel tank as described in any one of claims 1-9 is used to store fuel required for the flight of the aircraft and to supply fuel to the power system of the aircraft, thereby providing fuel supply support for the power system.

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