Thermal fatigue test device for autorotation of test piece

Abstract

The invention discloses a thermal fatigue test device for autorotation of a test piece, and belongs to the technical field of thermal fatigue of materials. The device comprises a heating mechanism, a cooling mechanism, a mechanism and a mechanism, wherein the mechanism drives two test pieces of a test piece shaft through a chain wheel and a chain of a motor and can realize autorotation; and the mechanism realizes transverse expansion and contraction and exchange revolution of the two test pieces through an air cylinder. In the thermal fatigue test process of the test pieces, the heating mechanism and the cooling mechanism can heat and cool the two test pieces at the same time, and the air cylinder can control stretching and retracting of the test pieces and enables the test pieces to revolve at the same time. In the heating and cooling process of the test piece, the servo motor enables the test piece to rotate, so that the circumferential surface of the test piece can be uniformly heated even if the flame heat is not uniformly distributed in the heating process of the test piece. According to the invention, each part of the test piece can be heated more uniformly in the heating and cooling processes of the test piece, so that the test piece has the same temperature distribution in the circumferential direction.

Description

Technical Field

[0001] The invention relates to a thermal fatigue test device for specimen self-rotation, belonging to the technical field of material thermal fatigue. Background Art

[0002] In recent years, as emission regulations and fuel economy become more and more stringent, the degree of engine reinforcement has become higher and higher, and the thermal load of heated parts in the cylinder has increased accordingly. Therefore, the reliability problem caused by fatigue damage of parts has become increasingly serious. As an important component of the diesel engine combustion chamber, the test piece is in direct contact with high-temperature fuel gas, which makes the temperature higher, reduces the mechanical properties of the test piece material, and reduces the thermal fatigue life of the test piece. At the same time, the test piece is one of the key parts of the engine, and its fatigue life seriously affects the further development of the engine. Therefore, it is an important link to use fatigue test methods to determine the ultimate strength of the test piece in the process of engine design and manufacturing. At present, the test cycle of thermal fatigue test of test pieces on the bench is long and costly.

[0003] Therefore, the inventor disclosed a single-item flip-type thermal fatigue test device for engine pistons in CN107884165A in the early stage, and disclosed a piston thermal fatigue test device based on reciprocating motion through CN107490524A after improvement later. For large heated components such as engine cylinder heads, the inventor also disclosed a test method based on a scaled pattern through CN114720257A. At the same time, the inventor developed auxiliary devices such as those disclosed in CN203738637U and CN108106433A to better complete the thermal fatigue test of heated components.

[0004] The above-mentioned device and method use flame heating to simulate the heating process of parts, which not only reduces the test cost of heated parts, but also greatly shortens the research and development cycle of related parts. However, based on the above device and method, during the test, the flame is affected by the structure and airflow, and the distribution of the heating flame is not uniform, which causes the parts to be heated unevenly in the circumferential direction during the heating process. Therefore, it is necessary to provide a thermal fatigue test device for the self-rotation of the specimen, which can make the circumferential heating of the specimen more uniform during the heating process, so as to better simulate the actual cooling state of the heated parts. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a thermal fatigue test device for specimen self-rotation, which can make the specimen self-rotate during heating and cooling by a servo motor, so that the heat load of each part of a single specimen can be kept consistent during heating and cooling. In addition, it can also make the heating state of different specimens the same when multiple specimens are tested at the same time, thereby improving the test efficiency and ensuring the consistency of the test.

[0006] The technical solution adopted by the present invention is:

[0007] A thermal fatigue test device for specimen rotation, comprising a first rotation bearing 4, a first transmission shaft 5, a first transmission tooth 6, a first transmission chain 7, a servo motor 8, a revolving bearing seat 9, a base 10, a revolving bearing 11, a cylinder 12, a slide rail 13, a motor drive shaft 15, a second transmission chain 16, a second transmission tooth 17, a second rotation bearing 18, a first bearing seat 19, a second transmission shaft 20, a first specimen fixture 21, a first specimen 22, a frame 25, a second bearing seat 26, a second specimen fixture 27 and a second specimen 28;

[0008] The frame 25 is T-shaped, and the first bearing seat 19 and the second bearing seat 26 are respectively provided at both ends of the crossbeam. The first rotation bearing 4 and the second rotation bearing 18 are respectively fixed to the frame 25 through the second bearing seat 26 and the first bearing seat 19;

[0009] The cylinder 12 is fixed on the base 10; the revolving bearing 11 is fixed on the slide rail 13 through the revolving bearing seat 9, and the slide rail 13 is arranged along the longitudinal beam of the T-shaped frame (25) and fixed on the base 10; the end of the longitudinal beam of the T-shaped frame 25 is connected to a telescopic connecting rod, and the telescopic connecting rod is placed in the revolving bearing 11. The cylinder 12 can realize the retracting of the frame 25 along the slide rail (13) and the 360° rotation along the midpoint of the frame 25 after being retracted into place through the telescopic connecting rod, so as to realize the revolving of the test piece;

[0010] The first specimen 22 and the second specimen 28 are fixed on the second transmission shaft 20 and the first transmission shaft 5 respectively through the first specimen fixture 21 and the second specimen fixture 27, the large ends of the second transmission shaft 20 and the first transmission shaft 5 are respectively meshed with the second transmission chain 16 and the first transmission chain 7 through the second transmission teeth 17 and the first transmission teeth 6, the first transmission chain 7 and the second transmission chain 16 are respectively connected to the servo motor 8 through the transmission teeth on the motor drive shaft 15, and the servo motor 8 is fixed on the frame 25; the first specimen 22 and the second specimen 28 can be driven by the servo motor 8 to rotate 360° along the first transmission shaft 5 and the second transmission shaft 20 respectively to realize the self-rotation of the specimens.

[0011] Furthermore, it also includes a heating mechanism and a cooling mechanism, which are located on one side of the first specimen fixture 21 and the second specimen fixture 27, and the first specimen fixture 21 and the second specimen fixture 27 enter or exit the heating mechanism and the cooling mechanism through the telescopic connecting rod of the cylinder 12.

[0012] Furthermore, while the first specimen 22 enters the heating mechanism for heating, the second specimen 28 enters the cooling mechanism for cooling; while the first specimen 22 and the second specimen 28 are being heated and cooled, the motor drive shaft 15 of the servo motor 8 drives the first transmission shaft 5 and the second transmission shaft 20 to rotate through the first transmission chain 7 and the second transmission chain 15, so that the first specimen 22 and the second specimen 28 rotate, thereby achieving the same temperature gradient in each part of the first specimen 22 and the second specimen 28 during the heating and cooling process.

[0013] Furthermore, when the first test piece 22 and the second test piece 28 are respectively heated and cooled, the cylinder 12 contracts backwards, causing the first test piece 22 to exit the combustion chamber 24; the cylinder 12 rotates the entire frame 25 through the telescopic connecting rod, causing the frame 25 to produce an orbital motion, thereby realizing the exchange of the relative positions of the first test piece 22 and the second test piece 28.

[0014] Furthermore, the heating mechanism includes a combustion chamber 24 and a burner 24 .

[0015] Furthermore, the cooling mechanism includes a cooling water tank 1, a cooling nozzle 2 and a reflux water tank 3 capable of forming a cooling water circulation.

[0016] Furthermore, the large ends of the first transmission shaft 5 and the second transmission shaft 20 are respectively provided with teeth meshing with the first transmission chain 7 and the second transmission chain 16 .

[0017] Furthermore, the motor drive shaft 15 of the servo motor 8 is provided with teeth respectively meshing with the first transmission chain 7 and the second transmission chain 16 .

[0018] Furthermore, the servo motor 8 can set the rotation speed and the rotation angle, so that the rotation speed of the test piece can be adjusted, and the rotation angle range can also be adjusted.

[0019] Furthermore, both ends of the slide rail 13 can play a thrust role when the frame 25 is extended or retracted.

[0020] Furthermore, the cylinder 12 is composed of a telescopic cylinder and a rotary cylinder, wherein the reciprocating motion of the frame 25 is controlled by the telescopic cylinder, and the rotary motion of the frame 25 is controlled by the rotary cylinder.

[0021] The test method of the thermal fatigue test device for the self-rotation of the specimen of the present invention comprises:

[0022] (1) The first test piece 22 is set to be heated and the second test piece 28 is set to be cooled;

[0023] (2) The cylinder 12 pushes the frame 25 laterally toward the heating mechanism and the cooling mechanism to heat the first test piece 22 and push the second test piece 28 into the heating mechanism and the cooling mechanism positions;

[0024] (3) The first test piece 22 enters the combustion chamber 24, and the burner 23 starts to ignite and heat the first test piece 22. At the same time, the second test piece 28 enters the cooling station, and the cooling nozzle 2 starts to spray water to cool the second test piece 28.

[0025] (4) While the first specimen 22 and the second specimen 28 are being heated and cooled, the servo motor 8 is started, and the motor drive shaft 15 drives the first transmission shaft 5 and the second transmission shaft 20 to rotate through the first transmission chain 7 and the second transmission chain 15, so that the first specimen 22 and the second specimen 28 rotate on their own, so as to ensure that the first specimen 22 and the second specimen 28 have the same temperature gradient in each part during the heating and cooling process;

[0026] (5) After the first test piece 22 and the second test piece 28 are heated and cooled respectively, the cylinder 12 retracts the frame backwards to make the first test piece 22 withdraw from the combustion chamber 24; then the cylinder 12 rotates the entire frame 25 to make the frame 25 generate an orbital motion, thereby exchanging the relative positions of the first test piece 22 and the second test piece 28; after the positions are exchanged, the cylinder 12 pushes the second test piece 28 into the combustion chamber 24 again, and the cooling nozzle starts to cool the first test piece 22;

[0027] (6) While the first specimen 22 and the second specimen 28 are being cooled and heated, the servo motor 8 is started, and the motor drive shaft 15 drives the first transmission shaft 5 and the second transmission shaft 20 to rotate through the first transmission chain 7 and the second transmission chain 15, so that the first specimen 22 and the second specimen 28 are self-rotated to ensure that the first specimen 22 and the second specimen 28 have the same temperature gradient in each part during the cooling and heating process;

[0028] (7) After the first test piece 22 and the second test piece 28 are cooled and heated respectively, the cylinder 12 retracts the frame backwards to make the first test piece 22 exit the combustion chamber 24; then the cylinder 12 rotates the entire frame 25 to make the frame 25 produce an orbital motion, thereby exchanging the relative positions of the first test piece 22 and the second test piece 28;

[0029] (8) Repeat the above steps (3) to (7) until the thermal fatigue test of the specimen is completed.

[0030] The beneficial effects of the present invention are:

[0031] (1) Allow the single specimen in the fixture to rotate simultaneously during heating and cooling so that each part is heated in the same state;

[0032] (2) When multiple specimens are tested simultaneously, it can ensure that different specimens in the fixture have the same thermal boundary conditions during heating and cooling, thus ensuring the consistency of the test;

[0033] (3) It can accurately simulate the actual heating state of the specimen, thereby accurately predicting the thermal fatigue life of the material, greatly reducing the cost of bench testing;

[0034] (4) Through the test device of the present invention, during the heating process of the test piece, even if the flame heat distribution is uneven, the circumferential surface of the test piece can be heated evenly, thereby better simulating the actual heating and cooling state of the test piece during the working process. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic diagram of the overall structure of the test device of the present invention.

[0036] In the figure: 1-cooling water tank, 2-cooling nozzle, 3-reflux water tank, 4-first rotation bearing, 5-first transmission shaft, 6-first transmission tooth, 7-first transmission chain, 8-servo motor, 9-first bearing seat, 10-base, 11-revolution bearing, 12-cylinder, 13-slide rail, 14-motor bolt, 15-output shaft, 16-second transmission chain, 17-second transmission tooth, 18-second rotation bearing, 19-first bearing seat, 20-second transmission shaft 20, 21-first specimen fixture, 22-first specimen, 23-combustion chamber, 24-burner, 25-frame, 26-second bearing seat, 27-second specimen fixture, 28-second specimen. DETAILED DESCRIPTION

[0037] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0038] Example 1

[0039] like Figure 1 As shown, a thermal fatigue test device for specimen rotation is characterized in that it includes a cooling water tank 1, a cooling nozzle 2, a reflux water tank 3, a first rotation bearing 4, a first transmission shaft 5, a first transmission tooth 6, a first transmission chain 7, a servo motor 8, a revolving bearing seat 9, a base 10, a revolving bearing 11, a cylinder 12, a slide rail 13, a motor bolt 14, a motor drive shaft 15, a second transmission chain 16, a second transmission tooth 17, a second rotation bearing 18, a first bearing seat 19, a second transmission shaft 20, a first specimen fixture 21, a first specimen 22, a combustion chamber 24, a burner 24, a frame 25, a second bearing seat 26, a second specimen fixture 27, and a second specimen 28;

[0040] The first test piece 22 and the second test piece 28 are fixed to the second transmission shaft 20 and the first transmission shaft 5 respectively through the first test piece fixture 21 and the second test piece fixture 27. The large ends of the second transmission shaft 20 and the first transmission shaft 5 respectively have the first transmission teeth 17 and the second transmission teeth 6 meshing with the second transmission chain 16 and the first transmission chain 7. The transmission chain is connected to the servo motor 8 through the transmission teeth on the motor drive shaft 15. The servo motor 8 is fixed to the frame 25 through the motor bolts 14.

[0041] The first rotation bearing 4 and the rotation bearing 18 are fixed to the frame through the second bearing seat 26 and the first bearing seat 19, and the servo motor 8 is fixed to the frame 25 through the motor bolts 14;

[0042] The revolving bearing 11 is fixed on the frame 25 through the revolving bearing seat 9 . The revolving bearing seat 9 is placed on the slide rail 13 . The slide rail 13 is installed on the base 10 .

[0043] Furthermore, the revolving bearing 11 can slide freely on the slide rail 13 .

[0044] The first transmission shaft 5 and the second transmission shaft 20 can rotate freely in the first rotation bearing 4 and the second rotation bearing 18 on both sides of the frame 25, thereby driving the test piece on the transmission shaft to rotate.

[0045] The large ends of the first transmission shaft 5 and the second transmission shaft 20 are respectively provided with teeth meshing with the first transmission chain 7 and the second transmission chain 16 .

[0046] The frame 25 is provided with a servo motor 8 , and the meshing teeth on the servo motor drive shaft 15 are respectively meshed with the first transmission chain 7 and the second transmission chain 16 , so that the first transmission shaft 5 and the second transmission shaft 20 can rotate synchronously.

[0047] Furthermore, the rotation speed and rotation angle of the servo motor 8 can be freely controlled, so that the rotation speed of the specimen can be adjusted, and the rotation angle range can also be adjusted. When a sensor is installed on the specimen, the data transmission line of the sensor will not be twisted.

[0048] The revolving bearing 11 is mounted on a slide rail 13 , and the slide rail 13 is mounted on the base 10 .

[0049] Furthermore, both ends of the slide rail 13 can play a thrust role.

[0050] Furthermore, the cylinder part is composed of a telescopic cylinder and a rotary cylinder, wherein the reciprocating motion of the frame is controlled by the telescopic cylinder, and the rotary motion of the frame is controlled by the rotary cylinder.

[0051] When the test piece self-rotation thermal fatigue test device of the present invention is working:

[0052] The cylinder 12 pushes the frame 25 toward the burner 24, so that the first test piece 22 enters the combustion chamber 24, and the burner 23 starts to ignite and heat the first test piece 22. At the same time, the second test piece 28 enters the cooling station, and the cooling nozzle 2 starts to spray water to cool the second test piece 28 until the second test piece 28 cools to the set temperature. While the first test piece 22 and the second test piece 28 are heated and cooled, the servo motor 8 is started, and the motor drive shaft 15 drives the first transmission shaft 5 and the second transmission shaft 20 to rotate through the first transmission chain 7 and the second transmission chain 15, so that the first test piece 22 and the second test piece 28 rotate, so as to ensure that the first test piece 22 and the second test piece 28 have the same temperature gradient in each part during the heating and cooling process.

[0053] When the first test piece 22 and the second test piece 28 are heated and cooled respectively, the cylinder 12 retracts the frame backwards to make the first test piece 22 withdraw from the combustion chamber 24. Then the cylinder 12 rotates the entire frame 25 to make the frame 25 produce an orbital motion, thereby exchanging the relative positions of the first test piece 22 and the second test piece 28. After the exchange of positions, the cylinder 12 pushes the second test piece 28 into the combustion chamber again, and the cooling nozzle starts to cool the first test piece 22.

[0054] The specific embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments. Various changes can be made within the knowledge scope of ordinary technicians in this field without departing from the purpose of the present invention.

Claims

1. A thermal fatigue test device for specimen rotation, characterized in that: The invention comprises a first self-rotating bearing (4), a first transmission shaft (5), a first transmission tooth (6), a first transmission chain (7), a servo motor (8), a revolving bearing seat (9), a base (10), a revolving bearing (11), a cylinder (12), a slide rail (13), a motor drive shaft (15), a second transmission chain (16), a second transmission tooth (17), a second self-rotating bearing (18), a first bearing seat (19), a second transmission shaft (20), a first specimen fixture (21), a first specimen (22), a frame (25), a second bearing seat (26), a second specimen fixture (27) and a second specimen (28); The frame (25) is T-shaped, and a first bearing seat (19) and a second bearing seat (26) are respectively arranged at both ends of the crossbeam; the first rotation bearing (4) and the second rotation bearing (18) are respectively fixed to the frame (25) through the second bearing seat (26) and the first bearing seat (19); The cylinder (12) is fixed on the base (10); the revolving bearing (11) is fixed on the slide rail (13) through the revolving bearing seat (9); the slide rail (13) is arranged along the longitudinal beam of the T-shaped frame (25) and fixed on the base (10); the end of the longitudinal beam of the T-shaped frame (25) is connected with a telescopic connecting rod, and the telescopic connecting rod is placed in the revolving bearing (11); the cylinder (12) can realize the frame (25) to be telescopic along the slide rail (13) and to rotate 360 ​​degrees along the midpoint of the frame (25) after being retracted to the right position through the telescopic connecting rod, so as to realize the revolving of the test piece; The first test piece (22) and the second test piece (28) are fixed on the second transmission shaft (20) and the first transmission shaft (5) respectively through a first test piece fixture (21) and a second test piece fixture (27); the large ends of the second transmission shaft (20) and the first transmission shaft (5) are meshed with the second transmission chain (16) and the first transmission chain (7) respectively through second transmission teeth (17) and first transmission teeth (6); the first transmission chain (7) and the second transmission chain (16) are connected to the servo motor (8) respectively through transmission teeth on the motor drive shaft (15); the servo motor (8) is fixed on the frame (25); the first test piece (22) and the second test piece (28) can be rotated 360 degrees along the first transmission shaft (5) and the second transmission shaft (20) respectively under the drive of the servo motor (8), so as to realize the self-rotation of the test pieces.

2. A thermal fatigue test device for specimen rotation according to claim 1, characterized in that: It also comprises a heating mechanism and a cooling mechanism, wherein the heating mechanism and the cooling mechanism are located on one side of the first specimen fixture (21) and the second specimen fixture (27), and the first specimen fixture (21) and the second specimen fixture (27) are enabled to enter or exit the heating mechanism and the cooling mechanism through the telescopic connecting rod of the cylinder (12).

3. A thermal fatigue test device for specimen rotation according to claim 2, characterized in that: The first test piece (22) enters the heating mechanism for heating while the second test piece (28) enters the cooling mechanism for cooling; while the first test piece (22) and the second test piece (28) are heated and cooled, the motor drive shaft (15) of the servo motor (8) drives the first transmission shaft (5) and the second transmission shaft (20) to rotate through the first transmission chain (7) and the second transmission chain (15), so that the first test piece (22) and the second test piece (28) generate self-rotation, so that each part of the first test piece (22) and the second test piece (28) has the same temperature gradient during the heating and cooling process.

4. A thermal fatigue test device for specimen rotation according to claim 3, characterized in that: When the first test piece (22) and the second test piece (28) have completed heating and cooling respectively, the cylinder (12) contracts backwards, causing the first test piece (22) to exit the combustion chamber (24); the cylinder (12) rotates the entire frame (25) through the telescopic connecting rod, causing the frame (25) to generate an orbital motion, thereby realizing the exchange of the relative positions of the first test piece (22) and the second test piece (28).

5. A thermal fatigue test device for specimen rotation according to any one of claims 1 to 4, characterized in that: The heating mechanism comprises a combustion chamber (24) and a burner (24); The cooling mechanism comprises a cooling water tank (1) capable of forming a cooling water circulation, a cooling nozzle (2) and a return water tank (3).

6. A thermal fatigue test device for specimen rotation according to any one of claims 1 to 4, characterized in that: The large ends of the first transmission shaft (5) and the second transmission shaft (20) are respectively provided with teeth meshing with the first transmission chain (7) and the second transmission chain (16).

7. A thermal fatigue test device for specimen rotation according to any one of claims 1 to 4, characterized in that: The motor drive shaft (15) of the servo motor (8) is provided with teeth respectively meshing with the first transmission chain (7) and the second transmission chain (16).

8. A thermal fatigue test device for specimen rotation according to any one of claims 1 to 4, characterized in that: The servo motor (8) can set the rotation speed and the rotation angle, so as to make the rotation speed and the rotation angle range of the test piece adjustable.

9. A thermal fatigue test device for specimen self-rotation according to any one of claims 1 to 4, characterized in that: The two ends of the slide rail (13) can play a thrust-stopping role when the frame (25) is telescoping.

10. A thermal fatigue test device for specimen rotation according to any one of claims 1 to 4, characterized in that: The cylinder (12) is composed of a telescopic cylinder and a rotary cylinder, wherein the reciprocating motion of the frame (25) is controlled by the telescopic cylinder, and the rotary motion of the frame (25) is controlled by the rotary cylinder.

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