CN112798408A - Large-opening fatigue test fixture for wing spar - Google Patents
Large-opening fatigue test fixture for wing spar Download PDFInfo
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- CN112798408A CN112798408A CN202011611050.5A CN202011611050A CN112798408A CN 112798408 A CN112798408 A CN 112798408A CN 202011611050 A CN202011611050 A CN 202011611050A CN 112798408 A CN112798408 A CN 112798408A
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- 238000009661 fatigue test Methods 0.000 title claims abstract description 16
- 238000012360 testing method Methods 0.000 claims abstract description 24
- 230000006835 compression Effects 0.000 claims description 2
- 238000007906 compression Methods 0.000 claims description 2
- 238000010008 shearing Methods 0.000 abstract description 8
- 238000005452 bending Methods 0.000 abstract description 4
- 238000005516 engineering process Methods 0.000 abstract 1
- 230000007704 transition Effects 0.000 abstract 1
- 238000003466 welding Methods 0.000 description 4
- 230000005540 biological transmission Effects 0.000 description 3
- 238000010891 electric arc Methods 0.000 description 2
- 239000002828 fuel tank Substances 0.000 description 2
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
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Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/02—Details
- G01N3/04—Chucks
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
- B25B—TOOLS OR BENCH DEVICES NOT OTHERWISE PROVIDED FOR, FOR FASTENING, CONNECTING, DISENGAGING OR HOLDING
- B25B11/00—Work holders not covered by any preceding group in the subclass, e.g. magnetic work holders, vacuum work holders
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64F—GROUND OR AIRCRAFT-CARRIER-DECK INSTALLATIONS SPECIALLY ADAPTED FOR USE IN CONNECTION WITH AIRCRAFT; DESIGNING, MANUFACTURING, ASSEMBLING, CLEANING, MAINTAINING OR REPAIRING AIRCRAFT, NOT OTHERWISE PROVIDED FOR; HANDLING, TRANSPORTING, TESTING OR INSPECTING AIRCRAFT COMPONENTS, NOT OTHERWISE PROVIDED FOR
- B64F5/00—Designing, manufacturing, assembling, cleaning, maintaining or repairing aircraft, not otherwise provided for; Handling, transporting, testing or inspecting aircraft components, not otherwise provided for
- B64F5/60—Testing or inspecting aircraft components or systems
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M13/00—Testing of machine parts
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Analytical Chemistry (AREA)
- Aviation & Aerospace Engineering (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Transportation (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Mechanical Engineering (AREA)
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
The invention belongs to the aviation strength test technology, and relates to a clamp design for a large opening fatigue test of an airplane wing spar. The two sections of wing spars are combined back to back through the clamp, and the loading feasibility is ensured. The invention keeps the bending moment of the wing beam checking part and the shearing force of the beam web plate in the test piece consistent with the real load, and ensures that the load transfer is uniform, the load eccentricity is eliminated, and the transition section is prevented from being damaged in advance in the test.
Description
Technical Field
The invention belongs to the technical field of structural strength tests, and particularly relates to a large-opening fatigue test clamp for a wing spar.
Background
The whole fuel tank of the airplane wing is positioned in the central wing box section, a plurality of fuel system through holes with larger apertures are arranged at the front and rear beam webs of the fuel tank, the whole bearing capacity of the wing beam structure is weakened more by the large opening, the fatigue life of the wing beam structure is directly influenced, and the design of the test piece clamp is the key for ensuring the smooth performance of the test.
The existing large opening fatigue test of the wing beam adopts a single beam for testing, and the test proves that the design has the following defects: 1. for spars with asymmetric cross-sections, single beam loading is prone to twist; 2. in the load transfer process, the wing beam checking part not only needs to ensure bending moment and shearing force, but also can ensure that the axis of the load and the centroid of the wing beam are eccentric by adopting a single beam, so that the authenticity of the checking section load cannot be ensured.
Disclosure of Invention
The invention aims to provide a large-opening fatigue test clamp for a wing spar, which can prevent the wing spar from being distorted and is convenient for test loading; the whole wing spar checking section realizes back-to-back combination design, one end is fixedly supported, the other end applies shearing force, authenticity of load is guaranteed, load transmission is uniform, and eccentric loading is eliminated.
In order to achieve the purpose, the invention is realized by adopting the following technical scheme.
The utility model provides a big opening fatigue test anchor clamps of spar for make up two sections spars back to back, its characterized in that, it comprises loading end and clamping end, and wherein, the loading end contains: a loading joint 3 and a connecting plate 4; the holding end includes: the connecting angle box 5, the T-shaped joint 6 and the adapter plate 7 are connected;
the loading end is connected with one end of the two wing beams together, and the clamping end is connected with the other end of the two wing beams together.
The technical scheme of the invention is further improved as follows:
(1) the two spars are two spars in the large-opening test piece, and the two spars are combined into the large-opening test piece through an upper skin and a lower skin.
(2) The connection plate 4 includes: an upper connecting plate and a lower connecting plate; the upper connecting plate connects the upper edge strip of the loading joint 3 with the upper skin and the upper edge strips of the two wing spars; the lower connecting plate connects the lower edge strip of the loading joint 3 with the lower skin and the lower edge strips of the two spars.
(3) The webs of the two spars are each connected to the web of the loading connection 3.
(4) The connecting angle box 5, the T-shaped joint 6 and the adapter plate 7 are connected;
the connection corner box 5 includes: the upper connecting angle box and the lower connecting angle box; the horizontal plane of the upper connecting angle box connects the upper edge strips and the upper skin of the two wing spars together, and the vertical plane of the upper connecting angle box is connected with the adapter plate together; the horizontal plane of the lower connecting angle box connects the lower edge strips of the two wing spars and the lower skin together, and the vertical plane of the lower connecting angle box is connected with the adapter plate together.
(5) The bottom end of the T-shaped joint 6 is fixedly connected to the middle of the adapter plate 7, and the vertical ends of the T-shaped joint 6 are respectively connected with the webs of the two wing beams.
(6) The loading joint 3 is provided with loading holes for applying concentrated load.
(7) Concentrated load is applied to the end of the loading joint, the load direction is perpendicular to the axis of the wing beam, after the large-opening test piece is subjected to the load perpendicular to the axis of the wing beam, the lower edge strip of the loading joint is pulled, the upper edge strip is pressed, and the web plate of the loading joint is sheared; the compression and tension loads borne by the upper edge strip and the lower edge strip of the loading joint are transmitted to the upper edge strip and the lower edge strip of the two wing spars through the connecting plates and then transmitted to the adapter plate through the connecting angle boxes;
the shear force on the loading joint web plate is transferred to the two wing beam web plates, the shear force is transferred to the T-shaped joint at the clamping end of the large-opening test piece, and then the shear force is transferred to the adapter plate;
and finally, transferring the load on the adapter plate to the bearing wall.
The technical scheme of the invention can 1) prevent wing spars from twisting, thereby facilitating test loading; 2) the whole wing spar checking section realizes back-to-back combined design, one end is fixedly supported, the other end applies shearing force, authenticity of load is guaranteed, load transmission is uniform, loading eccentricity is eliminated, and meanwhile, the shearing force of the checking part is guaranteed to be consistent with bending moment and real load.
Drawings
FIG. 1 is a schematic structural view of a large opening fatigue test piece and a test fixture for a wing spar;
FIG. 2 is a side view of FIG. 1;
FIG. 3 is a cross-sectional view of FIG. 1;
FIG. 4 is a schematic structural view of a load coupling;
FIG. 5 is a schematic view of the structure of the junction box;
FIG. 6 is a schematic structural view of a T-joint;
FIG. 7 is a top view of a clamping end configuration.
Detailed Description
The embodiment of the invention provides a large-opening fatigue test clamp for a wing spar of an airplane, which is shown in figure 1 and comprises a wing spar 1, a skin 2, a loading joint 3, a connecting plate 4, a connecting angle box 5, a T-shaped joint 6 and an adapter plate 7. FIG. 2 is a side view of FIG. 1; fig. 3 is a cross-sectional view of fig. 1.
The loading connector, the connecting plate, the connecting angle box, the T-shaped connector and the adapter plate are parts of a test piece clamp. The loading joint end applies a concentrated load in a direction perpendicular to the beam axis. Concentrated load is applied to the end of the loading joint, after the load perpendicular to the axis of the beam is applied, the lower edge strip of the loading joint is pulled, the upper edge strip is pressed, and the joint web plate is sheared. The pressure and tension loads on the upper and lower edge strips of the loading joint are transmitted to the upper and lower edge strips of the integral beam through the connecting plate and then transmitted to the adapter plate through the connecting angle box. The shear force on the loading joint web plate is transmitted to the wing beam web plate through the shear bolt, and the shear force is transmitted to the T-shaped joint at the fixed supporting end of the test piece and then transmitted to the adapter plate. Finally, the load on the adapter plate is transferred to the bearing wall through the tension shear of the bolt.
Fig. 4 is a schematic structural view of the loading joint.
The loading joint is combined by welding 30CrMnSiA plates and is subjected to manual electric arc welding. The thickness of the web plate is 40 mm, and the thickness of the upper edge strip and the lower edge strip is consistent with that of the upper edge strip and the lower edge strip of the beam. The loading joint edge strip is connected with the connecting plate through 16 30CrMnSiA bolts, the connecting plate is 2024-T351, and the thickness of the connecting plate is consistent with that of the beam edge strip. The loading joint and the web are connected through 16 30CrMnSiA bolts. The loading tab thickness was 40 mm. The connecting plate is connected with the upper and lower edge strips through 16 30CrMnSiA bolts, the connecting plate is 2024-T351, and the thickness of the connecting plate is consistent with that of the upper and lower edge strips of the beam.
As shown in fig. 5, which is a schematic structural diagram of the connection corner box, the upper and lower edge strips are connected with the connection corner box.
The connecting angle box is a 30CrMnSiA forge piece. The upper and lower edge strips are connected with the connecting angle box through bolts, and the bolts are subjected to single shearing. The thickness of the connecting surface of the connecting angle box is slightly smaller than that of the beam flange strip.
The adapter plate material is 30CrMnSiA and has a thickness of 45 mm. The connecting angle box is connected with the adapter plate through 4 bolts, and the bolts are pulled.
As shown in fig. 6, it is a schematic structural view of a T-junction.
The T-shaped joint is a 30CrMnSiA plate welding combination and is subjected to manual electric arc welding. The thickness of the web is 40 mm, and the thickness of the bottom plate is 20 mm. The connection form of the web plate and the T-shaped joint is completely the same as that of the loading joint. The T-shaped joint is connected with the adapter plate through 8 30CrMnSiA bolts. The thickness of the connecting surface of the T-shaped joint is 20 mm, and the thickness of the adapter plate is 40 mm. The bolt is subjected to single shear.
The test piece adapter plate is fixedly connected with the bearing wall through 6 phi 50 bolts. These 6 bolts are simultaneously in tension. Conservatively, the upper and lower 4 bolts are in tension and shear simultaneously, with the middle 2 bolts.
Fig. 7 is a schematic structural view of the clamping end.
Through strength calculation, the design of the clamp meets the requirements of static strength and fatigue strength.
The working principle of the invention is as follows: the loading joint end applies a concentrated load in a direction perpendicular to the beam axis. Concentrated load is applied to the end of the loading joint, after the load perpendicular to the axis of the beam is applied, the lower edge strip of the loading joint is pulled, the upper edge strip is pressed, and the joint web plate is sheared. The pressure and tension loads on the upper and lower edge strips of the loading joint are transmitted to the upper and lower edge strips of the integral beam through the connecting plate and then transmitted to the adapter plate through the connecting angle box. The shear force on the loading joint web plate is transmitted to the wing beam web plate through the shear bolt, and the shear force is transmitted to the T-shaped joint at the fixed supporting end of the test piece and then transmitted to the adapter plate. Finally, the load on the adapter plate is transferred to the bearing wall through the tension shear of the 6 bolts.
The technical scheme of the invention can 1) prevent wing spars from twisting, thereby facilitating test loading; 2) the whole wing spar checking section realizes back-to-back combined design, one end is fixedly supported, the other end applies shearing force, authenticity of load is guaranteed, load transmission is uniform, loading eccentricity is eliminated, and meanwhile, the shearing force of the checking part is guaranteed to be consistent with bending moment and real load.
Claims (7)
1. The utility model provides a big opening fatigue test anchor clamps of spar for make up two sections spars back to back, its characterized in that, it comprises loading end and clamping end, and wherein, the loading end contains: a loading joint (3) and a connecting plate (4); the holding end includes: the connecting angle box (5), the T-shaped joint (6) and the adapter plate (7);
the loading end is connected with one end of the two wing beams together, and the clamping end is connected with the other end of the two wing beams together.
2. The large-opening fatigue test fixture for the wing spar according to claim 1, wherein the two wing spars are two wing spars in a large-opening test piece, and the two wing spars are combined into the large-opening test piece through an upper skin and a lower skin;
the connection plate (4) comprises: an upper connecting plate and a lower connecting plate; the upper connecting plate connects the upper edge strip of the loading joint (3) with the upper skin and the upper edge strips of the two wing spars; the lower connecting plate connects the lower edge strip of the loading joint (3) with the lower skin and the lower edge strips of the two wing spars.
3. A spar large opening fatigue test fixture according to claim 2, characterized in that the webs of two spars are connected to the webs of the load joints (3), respectively.
4. The large-opening fatigue test fixture for wing spar according to claim 2, wherein the connecting angle box (5), the T-shaped joint (6) and the adapter plate (7)
The connection corner box (5) comprises: the upper connecting angle box and the lower connecting angle box; the horizontal plane of the upper connecting angle box connects the upper edge strips and the upper skin of the two wing spars together, and the vertical plane of the upper connecting angle box is connected with the adapter plate together; the horizontal plane of the lower connecting angle box connects the lower edge strips of the two wing spars and the lower skin together, and the vertical plane of the lower connecting angle box is connected with the adapter plate together.
5. The large-opening fatigue test fixture for the wing spar according to claim 2, wherein the bottom end of the T-shaped joint (6) is fixedly connected to the middle part of the adapter plate (7), and the vertical ends of the T-shaped joint (6) are respectively connected with the webs of the two wing spars.
6. The fatigue test fixture for large opening of wing spar according to claim 2,
the loading joint (3) is provided with a loading hole for applying concentrated load.
7. The large opening fatigue test fixture for the wing spar according to claim 6, wherein the loading joint end applies a concentrated load, the load direction is perpendicular to the axis of the wing spar, after the large opening test piece is subjected to the load perpendicular to the axis of the wing spar, the lower edge strip of the loading joint is pulled, the upper edge strip is pressed, and the web of the loading joint is sheared;
the compression and tension loads borne by the upper edge strip and the lower edge strip of the loading joint are transmitted to the upper edge strip and the lower edge strip of the two wing spars through the connecting plates and then transmitted to the adapter plate through the connecting angle boxes;
the shear force on the loading joint web plate is transferred to the two wing beam web plates, the shear force is transferred to the T-shaped joint at the clamping end of the large-opening test piece, and then the shear force is transferred to the adapter plate;
and finally, transferring the load on the adapter plate to the bearing wall.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011611050.5A CN112798408A (en) | 2020-12-29 | 2020-12-29 | Large-opening fatigue test fixture for wing spar |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011611050.5A CN112798408A (en) | 2020-12-29 | 2020-12-29 | Large-opening fatigue test fixture for wing spar |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112798408A true CN112798408A (en) | 2021-05-14 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011611050.5A Pending CN112798408A (en) | 2020-12-29 | 2020-12-29 | Large-opening fatigue test fixture for wing spar |
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| CN (1) | CN112798408A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113340711A (en) * | 2021-06-11 | 2021-09-03 | 中国飞机强度研究所 | Reinforced wallboard static fatigue load application test device |
| CN113465856A (en) * | 2021-08-31 | 2021-10-01 | 中国航天空气动力技术研究院 | Cabin body frequency modulation tool |
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| CN202869905U (en) * | 2012-07-06 | 2013-04-10 | 中国航空工业集团公司西安飞机设计研究所 | Aircraft wing web curved scissor test device |
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2020
- 2020-12-29 CN CN202011611050.5A patent/CN112798408A/en active Pending
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113340711A (en) * | 2021-06-11 | 2021-09-03 | 中国飞机强度研究所 | Reinforced wallboard static fatigue load application test device |
| CN113465856A (en) * | 2021-08-31 | 2021-10-01 | 中国航天空气动力技术研究院 | Cabin body frequency modulation tool |
| CN113465856B (en) * | 2021-08-31 | 2022-01-04 | 中国航天空气动力技术研究院 | Cabin body frequency modulation tool |
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Application publication date: 20210514 |
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