A furnace device for testing high temperature tensile tests of airtight graphite materials

Abstract

The present invention provides a furnace body device for testing high-temperature tensile tests of airtight graphite materials, comprising a fixed furnace body, the fixed furnace body is fixedly mounted on a body of a testing machine, a tensile platform and a clamp assembly are installed inside the fixed furnace body, and the clamp assembly comprises a lower clamp unit and an upper clamp group; a movable furnace body, the movable furnace body is slidably mounted on a bracket of the testing machine; a replacement part, the replacement part is used to replace samples for tensile tests inside the furnace body; and a power part; by arranging a first clamp group, a second clamp group and a replacement part in the fixed furnace body, it is achieved that tensile tests are performed on samples in the furnace body in batches without opening the furnace body, and multiple batches of tensile tests can be completed at one time. Compared with the traditional method, it not only saves the trouble of opening and closing the furnace body, but also does not need to heat and keep the furnace body warm again, thereby improving work efficiency, saving heating energy consumption, and reducing test costs.

Description

Technical Field

[0001] The invention relates to the technical field of graphite performance detection, and in particular to a furnace device for testing high-temperature tensile tests of airtight graphite materials. Background Art

[0002] Impermeable graphite is an excellent non-metallic material that is both corrosion-resistant and heat-conductive. Impermeable graphite has excellent corrosion resistance, thermal conductivity, small thermal expansion coefficient and good mechanical processing performance. It is widely used in industry as corrosion-resistant heat exchangers and equipment linings. The mechanical strength of impermeable graphite is not high, and its mechanical strength testing at room temperature and high temperature is particularly important. At present, the mature tensile strength testing method of impermeable graphite is limited to room temperature, and there are few specific schemes for testing at high temperature.

[0003] Chinese patent CN 108106946 A discloses a device and method for testing the high-temperature tensile properties of graphite workpieces. The device includes a base, a bracket, a pedestal, a pressure piece, a mobile platform, a clamp, a connecting rod, an insulation box, a heating pipe and a slide rail. The device has a movable heating device, which is an insulation box and a heating pipe wrapped around the insulation box. The heating device heats and keeps the workpiece fixed by the clamp for a period of time, and then applies tension to the workpiece to measure the tensile properties of the workpiece to be tested. The device can also measure the compressive properties of the workpiece. When measuring the compressive properties, the device will not heat the workpiece. The present invention can detect both the tensile properties and the compressive properties of the workpiece.

[0004] However, there are still some problems in this technical solution. When conducting high-temperature tensile tests on graphite, multiple groups of tests are required to obtain more accurate results. The above solution can only stretch a batch of samples at a time, and cannot complete batch tensile tests on graphite samples at one time in a closed high-temperature environment. Graphite needs to be maintained at a specific high temperature for stretching. When the furnace is opened to replace the graphite sample, the temperature in the furnace and the temperature of the graphite will decrease. Therefore, the graphite sample needs to be heated or kept warm again, which not only reduces the work efficiency, but also increases the heat energy consumption and the test cost by reheating or keeping warm the graphite sample. The above solution does not effectively solve these problems. Summary of the invention

[0005] The purpose of the present invention is to address the deficiencies in the prior art and to provide a furnace device for high-temperature tensile testing of airtight graphite materials. By arranging a first clamp group, a second clamp group and a replacement part in a fixed furnace body, it is possible to perform tensile tests on samples in the furnace body in batches without opening the furnace body, and multiple batches of tensile tests can be completed at one time; by arranging a concentric mechanism, when the sample enters the interior of the upper clamp, the position of the upper clamp is automatically adjusted so that the clamps at both ends of the sample remain concentric; by arranging a tightening unit, the upper clamp that has completed the concentric correction is tightened.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A furnace body device for testing high-temperature tensile tests of airtight graphite materials, comprising a fixed furnace body, the fixed furnace body being fixedly mounted on a body of a testing machine, a tensile table and a fixture assembly being mounted inside the fixed furnace body, the tensile table being used for performing tensile tests, the fixture assembly being used for fixing samples, the fixture assembly comprising a lower fixture unit and an upper fixture group, the lower fixture unit comprising a first fixture group and a second fixture group, a vacuum unit, an air charging unit, a heating unit and a temperature control unit being mounted on the body; specifically, the testing machine adopts a universal testing machine capable of performing tensile tests, the universal testing machine comprising a body, a bracket and a guide rail;

[0008] A movable furnace body, wherein the movable furnace body is slidably mounted on a bracket of the testing machine, and a furnace door is arranged on the movable furnace body; specifically, a guide rail for moving the movable furnace body is arranged on the bracket;

[0009] A replacement part, the replacement part is used to replace the sample for tensile test inside the furnace body, the replacement part includes an operating rod, and the operating rod is used to push the clamp assembly;

[0010] The power unit is used to control the movement of the operating rod. Specifically, the power unit can be an electric telescopic rod connected to the operating rod.

[0011] Through this setting, all samples can be placed in the furnace body, and all samples in the furnace body can be subjected to tensile tests without opening the furnace body. The function of completing multiple batches of tensile tests at one time saves the trouble of opening and closing the furnace body, and there is no need to heat and keep the furnace body warm again, which improves work efficiency, saves heating energy and reduces test costs.

[0012] As a preferred embodiment, the first clamp group and the second clamp group both include a plurality of lower clamps, which are slidably mounted in a fixed furnace body, a support frame is fixedly mounted inside the fixed furnace body, and the upper clamp group includes a plurality of upper clamps, which are movably mounted inside the support frame, the upper clamp is located above the lower clamp, and a concentric mechanism is mounted on the upper clamp. Specifically, hook plates for clamping samples are provided on both the upper clamp and the lower clamp, and the bottom end of the sample is fixed on the lower clamp. Before closing the furnace door, the upper clamp is adjusted so that the first clamp group and the upper clamp are kept concentric up and down, so as to measure more accurate test data; after the second clamp group is moved to the inside of the stretching table, the upper clamp is adjusted again through the concentric mechanism so that the second clamp group and the upper clamp are kept concentric up and down, which improves the problem that after the sample is replaced, the clamps at both ends of the sample are not concentric, and the sample is stretched to generate a twisting force, which easily leads to a large deviation in the tensile test data, thereby improving the accuracy of the test results.

[0013] As another preferred embodiment, the concentric mechanism includes a movable plate, which is movably inserted into the top end of the upper clamping plate, and a plurality of jaws are rotatably installed on the inner top wall of the upper clamping plate, the jaws are used to clamp the sample, and the jaws are movably connected to the movable plate through a connecting rod, and symmetrically distributed spring parts are installed on the outer side of the upper clamping plate, and a driving unit for controlling the movable plate is installed inside the movable furnace body. Specifically, in the initial state, the movable plate is located at the bottom of its moving position under the action of its own gravity, and the clamping jaws are retracted inside the inner top wall of the upper clamping plate, so that the top end of the sample can be smoothly inserted into the interior of the upper clamping plate; by designing and limiting the movement of the lower clamping unit, it is prevented from offsetting in the Y-axis and Z-axis directions. This process can be achieved through CNC programs or by setting guide slides. When replacing the sample, after the sample in the second clamping group is moved to the interior of the upper clamping plate, the movable plate is started to move up, and the upward movable plate drives all the clamping jaws to rotate synchronously through the connecting rod, so that the clamping jaws are clamped on the outside of the top end of the sample. If the upper clamping plate is not aligned with the top end of the sample in the Y-axis direction, the clamping jaws and the top end of the sample generate a force along the X-axis direction. By setting all the clamping jaws to move synchronously, according to the interaction of forces, the clamping jaws will push the upper clamping plate to move in the X-axis direction until the upper clamping plate and the top end of the sample are aligned in the Y-axis direction, thereby improving the concentricity of the clamps at both ends of the sample in the tensile test.

[0014] As another preferred embodiment, the driving unit includes a push rod, which is mounted on the movable furnace body, and is provided with a slope surface for lifting the movable plate, and the movable plate is provided with a through slot corresponding to the push rod inside. Specifically, after the movable furnace body moves to align with the fixed furnace body, the push rod on the movable furnace body contacts the movable plate and presses the movable plate to move upward, thereby realizing the function of automatically adjusting the concentricity of the first clamp and the upper clamping plate, and there is no need to calibrate the first clamp and the upper clamping plate separately, which saves the trouble of calibration, improves work efficiency, and is convenient to use.

[0015] As a preferred embodiment, the upper clamping plate is also provided with a fastening unit, which is used to fix the sample. The outer side of the upper clamping plate is provided with an ear plate. The fastening unit includes a pressure plate, which is used to squeeze and fix the ear plate. A threaded rod is fixedly installed on the pressure plate, and the threaded rod is rotatably installed inside the support frame. A driven gear is fixedly installed on the top of the threaded rod. A threaded groove corresponding to the threaded rod is provided inside the support frame. A tooth segment matching the driven gear is provided on the push rod. Specifically, during the movement of the push rod, after the movable plate is lifted up by the ramp surface, the tooth segment on the push rod contacts the driven gear, and drives the driven gear and the threaded rod to rotate. The threaded rod rotates and moves upward, and drives the pressure plate to move upward. The upward pressure plate abuts against the ear plate, thereby fixing the upper clamping plate, so that the upper clamping plate of the movable structure can remain fixed after the correction is completed. The problem that the upper clamping plate may shake due to not being fixed during the tensile test, which affects the test results, is improved, and the accuracy of the test is improved. The process is automatic, simple in structure, and easy to use.

[0016] As a preferred embodiment, the pressure plate is symmetrically distributed on the outer side of the upper clamping plate, the driven gear includes two groups of gears, and the push rod is provided with tooth segments matching the two groups of driven gears, and the tooth heights of the two groups of tooth segments are different, and the matching spacings between the two groups of gears and the tooth segments are different. Specifically, when the push rod moves, its moving direction is along the negative direction of the X-axis, the tooth height of the left tooth segment is smaller than the tooth height of the right tooth segment, and the left tooth segment does not contact the driven gear on the right; through this arrangement, the left tooth segment will not affect the driven gear on the right. After the push rod moves to the left, when the tooth segments on the left and right sides of the upper clamping plate are in contact with the driven gear, the left and right groups of screws rotate at the same time, so that all the pressure plates move up at the same time and tighten the upper clamping plate. The left-right symmetrical structural distribution makes the upper clamping plate more evenly stressed, which improves the problem that the upper clamping plate is prone to shaking and offset due to uneven stress on both sides.

[0017] As a preferred embodiment, the push rod is slidably installed inside the movable furnace body, a return spring is installed on the push rod, a push plate for pushing the push rod is rotatably installed on the operating rod, an elastic clamp is provided to move the push plate away from the push rod, a groove corresponding to the movable plate is provided inside the push rod, the side wall of the groove is sloped, and a baffle corresponding to the push rod is installed on the support frame. Specifically, according to the specific situation, a gap is left between the second clamp group and the first clamp group, or a gap is left between the operating rod and the second clamp group, so that the second clamp group will contact the first clamp group only after the operating rod moves a certain distance;

[0018] When replacing the sample, the operating rod is started to move along the negative direction of the X-axis. First, the push plate on the operating rod pushes the ejector rod to move so that the groove on the ejector rod is aligned with the movable plate, and then the movable plate moves along the negative direction of the Y-axis to separate the clamping jaws from the sample so that the sample in the first clamp group can be moved. Then, the operating rod pushes the second clamp group to the inside of the stretching table; then, the ejector rod contacts the baffle plate and cannot move further, while the operating rod continues to move. The push plate on the operating rod is subjected to excessive force, squeezing the elastic card plate and deflecting it. Then, the ejector rod is reset under the action of the reset spring, so that the ejector rod pushes the movable plate upward again, and the clamping jaw performs concentric correction on the upper clamp plate again; through this arrangement, the top end of the sample in the first clamp group is first loosened to facilitate pushing the first clamp group away, and the upper clamp plate cooperating with the second clamp group is concentrically corrected. This process is carried out automatically without manual operation, and has a simple structure and is easy to use.

[0019] As a preferred embodiment, a return torsion spring is installed on the push plate, and the rotating end of the push plate is staggered with the push rod. Specifically, in the initial state, when the push rod moves along the negative direction of the X-axis with the movable furnace body, it will squeeze the push plate to deflect to the left, so that the push rod can smoothly move to the left side of the push plate.

[0020] As another preferred embodiment, the operating rod is provided with a handle, the handle extends to the outside of the fixed furnace body, and a heat insulating sealing pad is installed on the handle. Specifically, the power unit for controlling the operating rod can be installed on the outside of the furnace body, which is convenient for subsequent operation and maintenance.

[0021] As another preferred embodiment, a receiving groove is provided inside the fixed furnace body, and a receiving plate is provided on the inner wall of the furnace door, and the receiving plate is located below the upper clamping plate. After the furnace door is closed, the receiving plate is close to the upper clamping plate. When the sample is replaced, the samples in the first clamp and the tightening plate will be broken, and the second clamp group pushes the first clamp group to move, and the first clamp group moves to the receiving groove. At the same time, the sample to be tested in the second clamp group pushes the broken sample in the upper clamping plate into the receiving plate. Since graphite is relatively brittle, this arrangement is used to prevent the broken sample in the upper clamping plate from falling directly onto the inner bottom wall of the fixed furnace body. The falling distance is too long, the falling impact force is too large, and it may be deflected and fall into the second clamp group, affecting the sample to be tested, or causing too much debris, which causes troubles in cleaning.

[0022] The beneficial effects of the present invention are:

[0023] (1) The present invention arranges a first clamp group, a second clamp group and a replacement part in a fixed furnace body, thereby realizing the tensile test of samples in the furnace body in batches without opening the furnace body, and multiple batches of tensile tests can be completed at one time. Compared with the traditional method, it not only saves the trouble of opening and closing the furnace body, but also eliminates the need to heat and keep the furnace body warm again, thereby improving work efficiency, saving heating energy consumption, and reducing test costs.

[0024] (2) The present invention provides a concentric mechanism to automatically adjust the position of the upper clamp when the sample enters the interior of the upper clamp, so that the clamps at both ends of the sample remain concentric. This improves the problem that when the sample is stretched, the clamps at both ends of the sample are not concentric, which easily leads to large deviations in the tensile test data, thereby improving the accuracy of the test results.

[0025] (3) The present invention provides a fastening unit to fasten the upper clamp after the sample enters the interior of the upper clamp and completes the concentric correction of the upper clamp. This improves the problem that during the tensile test, the upper clamp may shake due to not being fixed, thereby affecting the test results, and further improves the accuracy of the test.

[0026] (4) The present invention provides a push rod on the movable furnace body. After the movable furnace body moves to align with the fixed furnace body, the push rod on the movable furnace body contacts the movable plate and squeezes the movable plate to move upward, thereby realizing the function of automatically adjusting the concentricity of the first clamp and the upper clamp. There is no need to calibrate the first clamp and the upper clamp separately, which saves the trouble of calibration, improves work efficiency and is easy to use.

[0027] (5) The present invention provides an operating rod, which can automatically complete the replacement of samples, concentric correction and tightening of the upper clamping plate when the second clamping group is pushed, without the need for additional driving devices or manual operations. The structure is simple and easy to use.

[0028] In summary, the present invention has the advantages of replacing the sample to be tested in a high-temperature furnace body and automatically performing concentric correction and tightening of the fixture. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0030] Figure 2 It is a schematic diagram of a fixed furnace body and a movable furnace body;

[0031] Figure 3 Exploded view of the internal structure of the fixed furnace;

[0032] Figure 4 It is a schematic diagram of the cooperation between the ejector rod and the fixed furnace body;

[0033] Figure 5Schematic diagram of the upper splint and the lower splint;

[0034] Figure 6 It is a schematic diagram of the operating rod and the ejector rod;

[0035] Figure 7 It is a schematic diagram of the ejector rod and the pressure plate;

[0036] Figure 8 It is a cross-sectional view of the mounting structure of the clamping jaw and the upper clamping plate;

[0037] Fig. 9 Schematic diagram of the push plate;

[0038] Fig.10 This is a picture of the furnace door. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0041] Embodiment 1

[0042] like Figure 1-4 As shown, this embodiment provides a furnace device for testing high temperature tensile test of airtight graphite materials, including

[0043] A fixed furnace body 1 is fixedly mounted on a body 51 of the testing machine. A stretching table 11 and a fixture assembly are installed inside the fixed furnace body 1. The stretching table 11 is used to perform a tensile test. The fixture assembly is used to fix the sample 6. The fixture assembly includes a lower fixture unit and an upper fixture group 12. The lower fixture unit includes a first fixture group 13 and a second fixture group 14. A vacuum unit, an air charging unit, a heating unit 15 and a temperature control unit 16 are installed on the body 51. Specifically, the testing machine adopts a universal testing machine that can perform a tensile test. The universal testing machine includes a body 51, a bracket 52 and a guide rail 53. The vacuum unit includes a vacuum unit for the furnace. The vacuum pump for evacuating the furnace body, the gas charging unit includes a gas charging pump for introducing an inert gas into the furnace body, the heating unit 15 can adopt a ceramic heating element, the temperature control unit 16 includes two B-type platinum-rhodium thermocouples and a display analysis system, one platinum-rhodium thermocouple is used to measure the actual temperature control temperature in the furnace body, and the other platinum-rhodium thermocouple is used to measure the actual temperature of the sample 6. The display analysis system is a computer system, and the software in the computer system is used to control the loading speed during the test, display the force value curve, and calculate the strength of the sample 6. A variety of stretching tables 11 are equipped according to the standard of impermeable graphite to meet the requirements of different tests on the sample 6;

[0044] A movable furnace body 2, wherein the movable furnace body 2 is slidably mounted on a bracket 52 of the testing machine, and a furnace door 22 is arranged on the movable furnace body 2; specifically, a guide rail 53 for moving the movable furnace body 2 is arranged on the bracket 52;

[0045] A replacement part 3, the replacement part 3 is used to replace the sample 6 for the tensile test inside the furnace body, the replacement part 3 includes an operating rod 31, and the operating rod 31 is used to push the clamp assembly;

[0046] The power unit 4 is used to control the movement of the operating rod 31. Specifically, the power unit 4 can be an electric telescopic rod, which is connected to the operating rod 31.

[0047] In the initial state, the movable furnace body 2 is separated from the fixed furnace body 1, and cylindrical sections are provided at both ends of the sample 6 for easy clamping. When performing a high-temperature tensile test on the impermeable graphite sample 6, the operating steps are as follows:

[0048] 1. All samples 6 are installed in the lower fixture unit in the fixed furnace body 1. The bottom end of the sample 6 is installed in the first fixture group 13 and the second fixture group 14 and fixed by bolts and other devices. The first fixture group 13 is installed on the stretching table 11, and the second fixture group 14 is reserved for standby use.

[0049] 2. Open the furnace door 22 on the movable furnace body 2, move the movable furnace body 2 through the guide rail 53, align the movable furnace body 2 with the fixed furnace body 1, and then close the furnace door 22, and fix the movable furnace body 2 and the fixed furnace body 1 together by means of fastening bolts, etc. At this time, the fixed furnace body 1 and the movable furnace body 2 form a sealed furnace body, and the upper clamp group 12 clamps the top of the sample 6;

[0050] 3. Use a vacuum pump to evacuate the furnace body and pass inert gas. Repeat this operation 3 times, then pass inert gas to positive pressure and maintain it;

[0051] 4. Start the heating unit 15 and the temperature control unit 16, raise the temperature of the furnace to the temperature to be measured, and maintain it for at least 1 hour;

[0052] 5. Start the stretching table 11. The stretching table 11 and the upper clamp group 12 stretch the sample 6 in the first clamp group 13, start the mechanical property measurement, record the force value, and calculate;

[0053] 6. Start the operating rod 31 to push the second clamp set 14 to move. After the second clamp set 14 squeezes the first clamp set 13 out of the stretching platform 11, the second clamp set 14 moves to the inside of the stretching platform 11;

[0054] 7. Start the stretching platform 11. The stretching platform 11 and the upper clamp group 12 stretch the sample 6 in the second clamp group 14, start the mechanical property measurement, record the force value, and calculate.

[0055] Through this arrangement, it is possible to place all samples 6 in the furnace body, and perform tensile tests on all samples 6 in the furnace body without opening the furnace body, thereby completing the function of completing multiple batches of tensile tests at one time. Compared with the traditional method, it not only saves the trouble of opening and closing the furnace body, but also eliminates the need to heat and insulate the furnace body again, thereby improving work efficiency, saving heating energy consumption, and reducing test costs.

[0056] like Figure 2-3As shown, further, the first clamp group 13 and the second clamp group 14 each include a plurality of lower clamps 131, which are slidably installed in the fixed furnace body 1, and a support frame 17 is fixedly installed inside the fixed furnace body 1. The upper clamp group 12 includes a plurality of upper clamps 121, which are movably installed inside the support frame 17, and the upper clamps 121 are located above the lower clamps 131, and a concentric mechanism is installed on the upper clamps 121. Specifically, the upper clamp plate 121 and the lower clamp plate 131 are both provided with hook plates for clamping the sample 6, and the bottom end of the sample 6 is fixed on the lower clamp plate 131. Before closing the furnace door 22, the upper clamp plate 121 is adjusted so that the first clamp group 13 and the upper clamp plate 121 remain concentric up and down, so as to measure more accurate test data; after the second clamp group 14 is moved to the inside of the stretching table 11, the upper clamp plate 121 is adjusted again through the concentric mechanism so that the second clamp group 14 and the upper clamp plate 121 remain concentric up and down, thereby improving the problem that after replacing the sample 6, the clamps at both ends of the sample 6 are not concentric, and the sample 6 generates a twisting force when it is stretched, which easily leads to a large deviation in the tensile test data, thereby improving the accuracy of the test results.

[0057] like Figure 2-8 As shown, further, the concentric mechanism includes a movable plate 1211, which is movably plugged into the top of the upper clamping plate 121, and a plurality of clamping claws 1212 are rotatably mounted on the inner top wall of the upper clamping plate 121, and the clamping claws 1212 are used to clamp the sample 6, and the clamping claws 1212 are movably connected to the movable plate 1211 through a connecting rod 1214, and symmetrically distributed spring members 1213 are mounted on the outer side of the upper clamping plate 121, and a driving unit for controlling the movable plate 1211 is mounted inside the movable furnace body 2. Specifically, in the initial state, as shown in FIG. Figure 8As shown, the movable plate 1211 is located at the bottom of its moving position under the action of its own gravity (in order to improve the effect, a spring can also be installed on the movable plate 1211), and the clamping claw 1212 is retracted inside the inner top wall of the upper clamping plate 121, so that the top of the sample 6 can be smoothly inserted into the interior of the upper clamping plate 121; by designing and limiting the movement of the lower clamping unit, it does not cause deviation in the Y-axis and Z-axis directions. This process can be achieved by CNC programming or setting guide grooves. When replacing the sample 6, after the sample 6 in the second clamping group 14 moves to the interior of the upper clamping plate 121, the movable plate 1212 is started. 211 moves upward, and the upward movable plate 1211 drives all the jaws 1212 to rotate synchronously through the connecting rod 1214, so that the jaws 1212 are clamped on the outer side of the top of the sample 6. If the upper clamp plate 121 is not aligned with the top of the sample 6 in the Y-axis direction, the jaws 1212 and the top of the sample 6 will generate a force along the X-axis direction. By setting all the jaws 1212 to move synchronously, according to the interaction of forces, the jaws 1212 will push the upper clamp plate 121 to move in the X-axis direction until the upper clamp plate 121 is aligned with the top of the sample 6 in the Y-axis direction, thereby improving the concentricity of the clamps at both ends of the sample 6 in the tensile test.

[0058] like Figure 6-8 As shown, further, the driving unit includes a push rod 21, which is installed on the movable furnace body 2, and is provided with a slope surface for lifting the movable plate 1211, and the movable plate 1211 is provided with a through slot corresponding to the push rod 21. Specifically, after the movable furnace body 2 moves to align with the fixed furnace body 1, the push rod 21 on the movable furnace body 2 contacts the movable plate 1211 and presses the movable plate 1211 to move upward, realizing the function of automatically adjusting the concentricity of the first clamp and the upper clamp 121, and there is no need to calibrate the first clamp and the upper clamp 121 separately, which saves the trouble of calibration, improves work efficiency, and is convenient to use.

[0059] like Figure 3-7As shown, further, a fastening unit is installed on the upper clamping plate 121, and the fastening unit is used to fix the sample 6. An ear plate is arranged on the outer side of the upper clamping plate 121, and the fastening unit includes a pressure plate 122, and the pressure plate 122 is used to squeeze and fix the ear plate. A threaded rod 123 is fixedly installed on the pressure plate 122, and the threaded rod 123 is rotatably installed inside the support frame 17. A driven gear 124 is fixedly installed on the top of the threaded rod 123. A threaded groove corresponding to the threaded rod 123 is opened inside the support frame 17, and a tooth segment matching the driven gear 124 is arranged on the top rod 21. Specifically, during the movement of the push rod 21, after the movable plate 1211 is lifted up by the slope surface, the tooth segment on the push rod 21 contacts the driven gear 124, and drives the driven gear 124 and the threaded rod 123 to rotate. The threaded rod 123 moves upward while rotating, and drives the pressure plate 122 to move upward. The upward pressure plate 122 presses against the ear plate, thereby fixing the upper clamping plate 121, so that the upper clamping plate 121 of the movable structure can remain fixed after the correction is completed. The problem that the upper clamping plate 121 may shake and affect the test results due to not being fixed during the tensile test is improved, and the accuracy of the test is improved. The process is automatic, simple in structure, and easy to use.

[0060] like Figure 7 As shown, further, the pressure plate 122 is symmetrically distributed on the outer side of the upper clamping plate 121, the driven gear 124 includes two sets of gears, and the push rod 21 is provided with tooth segments matching the two sets of driven gears 124, and the tooth heights of the two sets of tooth segments are different, and the matching spacing between the two sets of gears and the tooth segments is different. Specifically, when the push rod 21 moves, its moving direction is to move along the negative direction of the X axis. Figure 7 In the middle, it moves from right to left, the tooth height of the left tooth segment is smaller than the tooth height of the right tooth segment, and the left tooth segment does not contact the driven gear 124 on the right; through this arrangement, the left tooth segment will not affect the driven gear 124 on the right, and after the top rod 21 moves to the left, when the tooth segments on the left and right sides of the upper clamping plate 121 are in contact with the driven gear 124, the left and right sets of screws rotate at the same time, so that all the pressure plates 122 move up at the same time and tighten the upper clamping plate 121. The left-right symmetrical structural distribution makes the upper clamping plate 121 more evenly stressed, which improves the problem of the upper clamping plate 121 shaking and deviating easily due to uneven stress on both sides.

[0061] like Figure 3-9As shown, further, the push rod 21 is slidably installed inside the movable furnace body 2, a return spring is installed on the push rod 21, a push plate 32 for pushing the push rod 21 is rotatably installed on the operating rod 31, and an elastic clamping plate 33 is provided to move the push plate 32 away from the push rod 21. A groove corresponding to the movable plate 1211 is provided inside the push rod 21, and the side wall of the groove is sloped, and a baffle 171 corresponding to the push rod 21 is installed on the support frame 17. Specifically, according to the specific situation, it is designed that a gap is left between the second clamp group 14 and the first clamp group 13, or a gap is left between the operating rod 31 and the second clamp group 14, so that the second clamp group 14 will contact the first clamp group 13 only after the operating rod 31 moves a certain distance;

[0062] When replacing the sample 6, the operating rod 31 is started to move along the negative direction of the X-axis. First, the push plate 32 on the operating rod 31 pushes the top rod 21 to move, so that the groove on the top rod 21 is aligned with the movable plate 1211, and then the movable plate 1211 moves along the negative direction of the Y-axis to separate the clamping jaws 1212 from the sample 6, so that the sample 6 in the first clamp group 13 can be moved. Then, the operating rod 31 pushes the second clamp group 14 to the inside of the stretching table 11; then, the top rod 21 contacts the baffle 171, and the top rod 21 cannot move further, while the operating rod 31 continues to move, then the operating rod 31 When the push plate 32 on the working rod 31 is subjected to excessive force, the elastic clamping plate 33 is squeezed and deflected, the push rod 21 is reset under the action of the reset spring, so that the push rod 21 pushes the movable plate 1211 upward again, and the clamping jaws 1212 perform concentric correction on the upper clamping plate 121 again; through this arrangement, the top of the sample 6 in the first clamp group 13 is first loosened to facilitate pushing the first clamp group 13 away, and the upper clamping plate 121 that cooperates with the second clamp group 14 is concentrically corrected. This process is carried out automatically without manual operation, with a simple structure and easy use.

[0063] like Figure 6 As shown, further, a return torsion spring is installed on the push plate 32, and the rotating end of the push plate 32 is staggered up and down with the push rod 21. Specifically, in the initial state, when the push rod 21 moves along the negative direction of the X-axis with the movable furnace body 2, it will squeeze the push plate 32 to deflect to the left, so that the push rod 21 can smoothly move to the left side of the push plate 32.

[0064] like Figure 6 As shown, further, the operating rod 31 is provided with a handle 311, the handle 311 extends to the outside of the fixed furnace body 1, and a heat insulating sealing pad is installed on the handle 311. Specifically, the power unit 4 for controlling the operating rod 31 can be installed on the outside of the furnace body, which is convenient for subsequent operation and maintenance.

[0065] Embodiment 2

[0066] like Fig.10As shown, the components identical or corresponding to those in the first embodiment are marked with the corresponding reference numerals in the first embodiment. For the sake of simplicity, only the differences from the first embodiment are described below. The second embodiment differs from the first embodiment in that:

[0067] In this embodiment, a receiving groove 18 is provided inside the fixed furnace body 1, and a receiving plate 221 is provided on the inner wall of the furnace door 22, and the receiving plate 221 is located below the upper clamping plate 121. After the furnace door 22 is closed, the receiving plate 221 is close to the upper clamping plate 121. When the sample 6 is replaced, the sample 6 in the first clamp and the tightening plate will be broken, and the second clamp group 14 pushes the first clamp group 13 to move, and the first clamp group 13 moves into the receiving groove 18. At the same time, the sample 6 to be tested in the second clamp group 14 pushes the broken sample 6 in the upper clamping plate 121 into the receiving plate 221. Since graphite is brittle, this arrangement is used to prevent the broken sample 6 in the upper clamping plate 121 from falling directly onto the inner bottom wall of the fixed furnace body 1. The falling distance is too long, the falling impact force is too large, and it may be deflected and fall into the second clamp group 14, affecting the sample 6 to be tested, or causing too much debris, which causes troubles in cleaning.

[0068] Working steps

[0069] Step 1: All samples 6 are installed in the lower fixture unit in the fixed furnace body 1. The bottom end of the sample 6 is installed in the first fixture group 13 and the second fixture group 14 and fixed by bolts and other devices. The first fixture group 13 is installed on the stretching table 11, and the second fixture group 14 is reserved for standby use.

[0070] Step 2: Open the furnace door 22 on the movable furnace body 2, and move the movable furnace body 2 through the guide rail 53 so that the movable furnace body 2 is aligned with the fixed furnace body 1. During this process, the top rod 21 on the movable furnace body 2 contacts the movable plate 1211 and presses the movable plate 1211 to move upward, thereby realizing the function of automatically adjusting the concentricity of the first clamp and the upper clamping plate 121. Then, close the furnace door 22, and fix the movable furnace body 2 and the fixed furnace body 1 together by means of fastening bolts and the like. At this time, the fixed furnace body 1 and the movable furnace body 2 form a sealed furnace body.

[0071] Step 3: Use a vacuum pump to evacuate the furnace body and pass inert gas. Repeat this operation 3 times, then pass inert gas to positive pressure and maintain it;

[0072] Step 4: Start the heating unit 15 and the temperature control unit 16, raise the temperature of the furnace to the temperature to be measured, and keep it for at least 1 hour;

[0073] Step 5: Start the stretching platform 11. The stretching platform 11 and the upper clamp group 12 stretch the sample 6 in the first clamp group 13, start the mechanical property measurement, record the force value, and calculate;

[0074] Step 6: Start the operating rod 31. After the operating rod 31 pushes the second clamp group 14 to move, the push plate 32 on the operating rod 31 pushes the push rod 21 to move, so that the groove on the push rod 21 is aligned with the movable plate 1211, and then the movable plate 1211 moves along the negative direction of the Y axis, so that the clamping jaws 1212 are separated from the sample 6, so that the sample 6 in the first clamp group 13 can be moved;

[0075] Next, the operating rod 31 pushes the second clamp set 14 into the interior of the stretching platform 11;

[0076] Subsequently, the push rod 21 contacts the baffle 171 and cannot move further, while the operating rod 31 continues to move. Then, the push plate 32 on the operating rod 31 is subjected to excessive force, which squeezes the elastic clamping plate 33 and causes deflection. Then, the push rod 21 is reset under the action of the reset spring, so that the push rod 21 pushes the movable plate 1211 upward again, and the clamping jaw 1212 performs concentric correction on the upper clamping plate 121 again.

[0077] Step 7, start the stretching table 11, the stretching table 11 and the upper clamp group 12 stretch the sample 6 in the second clamp group 14, start the mechanical property measurement, record the force value, and calculate;

[0078] The method of the invention is used to test the tensile strength of impermeable graphite at high temperature. The device has a simple structure, is easy to use, and has high reliability and stability.

[0079] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A furnace device for testing high temperature tensile tests of airtight graphite materials, characterized in that: Also includes: A fixed furnace body, wherein the fixed furnace body is fixedly mounted on the body of the testing machine, a stretching table and a fixture assembly are installed inside the fixed furnace body, the stretching table is used to perform a stretching test, the fixture assembly is used to fix the sample, the fixture assembly includes a lower fixture unit and an upper fixture group, the lower fixture unit includes a first fixture group and a second fixture group, and a vacuum unit, an air charging unit, a heating unit and a temperature control unit are installed on the body; A movable furnace body, the movable furnace body is slidably mounted on a bracket of the testing machine, and a furnace door is arranged on the movable furnace body; A replacement part, the replacement part is used to replace the sample for tensile test inside the furnace body, the replacement part includes an operating rod, and the operating rod is used to push the clamp assembly; A power unit, the power unit is used to control the movement of the operating rod; The first clamp group and the second clamp group each include a plurality of lower clamps, the lower clamps are slidably mounted in a fixed furnace body, a support frame is fixedly mounted inside the fixed furnace body, and the upper clamp group includes a plurality of upper clamps, the upper clamps are movably mounted inside the support frame, the upper clamps are located above the lower clamps, and a concentric mechanism is mounted on the upper clamps; The concentric mechanism includes a movable plate, which is movably plugged into the top end of the upper clamping plate. A plurality of jaws are rotatably mounted on the inner top wall of the upper clamping plate. The jaws are used to clamp the sample. The jaws are movably connected to the movable plate through a connecting rod. Symmetrically distributed spring parts are mounted on the outer side of the upper clamping plate. A driving unit for controlling the movable plate is mounted inside the movable furnace body.

2. A furnace device for testing high temperature tensile test of airtight graphite material according to claim 1, characterized in that: The driving unit comprises a push rod which is mounted on the movable furnace body. The push rod is provided with a slope surface for lifting the movable plate. A through groove corresponding to the push rod is provided inside the movable plate.

3. A furnace device for testing high temperature tensile test of airtight graphite material according to claim 2, characterized in that: A fastening unit is also installed on the upper clamping plate, and the fastening unit is used to fix the sample. An ear plate is arranged on the outer side of the upper clamping plate. The fastening unit includes a pressure plate, and the pressure plate is used to squeeze and fix the ear plate. A threaded rod is fixedly installed on the pressure plate, and the threaded rod is rotatably installed inside the support frame. A driven gear is fixedly installed on the top end of the threaded rod. A threaded groove corresponding to the threaded rod is opened inside the support frame, and a tooth segment matching the driven gear is arranged on the top rod.

4. A furnace device for testing high temperature tensile test of airtight graphite material according to claim 3, characterized in that: The pressure plate is symmetrically distributed on the outer side of the upper clamping plate, the driven gear includes two sets of gears, and the push rod is provided with tooth segments matching the two sets of driven gears, and the tooth heights of the two sets of tooth segments are different, and the matching spacings between the two sets of gears and the tooth segments are different.

5. A furnace device for testing high temperature tensile test of airtight graphite material according to claim 4, characterized in that: The push rod is slidably installed inside the movable furnace body, a return spring is installed on the push rod, a push plate for pushing the push rod is rotatably installed on the operating rod, an elastic clamping plate is provided to move the push plate away from the push rod, a groove corresponding to the movable plate is opened inside the push rod, the side wall of the groove is sloped, and a baffle corresponding to the push rod is installed on the support frame.

6. A furnace device for testing high temperature tensile test of airtight graphite material according to claim 5, characterized in that: A return torsion spring is installed on the push plate, and the rotating end of the push plate is staggered with the push rod up and down.

7. A furnace device for testing high temperature tensile test of airtight graphite material according to claim 1, characterized in that: The operating rod is provided with a handle, the handle extends to the outside of the fixed furnace body, and a heat insulation sealing pad is installed on the handle.

8. The furnace device for testing high temperature tensile test of airtight graphite material according to claim 1, characterized in that: A receiving groove is arranged inside the fixed furnace body, and a receiving plate is arranged on the inner wall of the furnace door, and the receiving plate is located below the upper clamping plate.

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