Device and method for improving strain measurement precision of high-temperature strain calibration device

Abstract

The invention provides a device and method for improving strain measurement precision of a high-temperature strain calibration device.The device comprises a mounting frame body, a mechanical strain measurement assembly and a loading assembly, part of the mounting frame body is arranged in a high-temperature furnace, and a calibration beam is connected with the mounting frame body and located in the high-temperature furnace; the mechanical strain measuring assembly comprises a feeler lever assembly, a measuring seat assembly and a grating ruler assembly, the measuring seat assembly comprises a measuring seat body and is connected with the mounting frame body, the feeler lever assembly comprises a feeler lever and a wing plate, the feeler lever sequentially penetrates through the measuring seat body, the wing plate and the mounting frame body and abuts against the calibration beam, the wing plate is fixedly connected with the measuring seat body, and the grating ruler assembly is fixedly connected with the measuring seat body. The grating ruler assembly comprises a grating ruler frame and a grating ruler, the grating ruler frame is connected with the mounting frame body, the grating ruler is connected with the wing plate, and the loading assembly is used for applying loading force to the calibration beam so that the calibration beam can deform towards the feeler lever. According to the device for improving the strain measurement precision of the high-temperature strain calibration device, the strain measurement precision of the high-temperature strain calibration device is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of high-temperature strain gauge measurement, and in particular to a device and method for improving the strain measurement accuracy of a high-temperature strain calibration device. Background Art

[0002] A strain gauge is a sensor that measures the deformation of materials and structures due to changes in stress, converting deformation into changes in electrical resistance. Its sensitivity coefficient represents the rate of change in resistance per unit of strain in the strain gauge. It characterizes the relationship between the measured physical quantity and the electrical signal and is one of the most important parameters of a strain gauge. Especially when conducting high-temperature strain measurements, the strain gauge's sensitivity coefficient varies with temperature. Therefore, precise calibration of the strain gauge's sensitivity coefficient at different temperatures is necessary to accurately measure high-temperature strain signals.

[0003] In related technologies, the calibration method for a four-point bending equal strain beam is to place the calibration beam in a blast furnace in a simply supported form, and apply left-right symmetrical and equal loads to it during calibration. The left and right ends are support points, and the area between the two loading points is an equal strain area. According to the deflection curve equation of material mechanics, the relationship between the strain of the equal strain segment of the calibration beam and the deflection of the calibration beam and its dimensional parameters can be obtained. Therefore, the mechanical strain value of the equal strain segment of the calibration beam can be obtained by measuring the change in the deflection of the calibration beam. There are three main methods for measuring the deflection of the calibration beam: the first is to measure the deflection change of the midpoint of the calibration beam through a feeler rod. This method will include the deformation of the calibration beam support mechanism and the thermal deformation of the feeler rod as the deformation of the calibration beam, resulting in inaccurate measurement results; the second is to measure the deflection of the midpoint of the calibration beam through non-contact methods such as laser ranging. This method does not use a feeler rod for measurement, but still cannot solve the error caused by the deformation of the calibration beam support mechanism; the third is to use a three-point deflection bracket. The bracket is installed on the calibration beam, and a displacement sensor is arranged at the midpoint of the bracket. The measurement result is the deflection difference between the bracket support point and the midpoint. The mechanical strain on the calibration beam is calculated based on the difference. This structure can eliminate the influence of the overall deformation of the support mechanism, but when conducting experiments at high temperatures, the problem of thermal deformation of the feeler rod cannot be eliminated. In addition, the three-point deflection bracket is placed in a high temperature environment as a whole. The deformation of the calibration beam affects the installation and positioning of the three-point deflection bracket, resulting in the poor applicability of this method at high temperatures. Summary of the Invention

[0004] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0005] To this end, an embodiment of the present invention proposes a device for improving the strain measurement accuracy of a high-temperature strain calibration device according to an embodiment of the present invention. The device improves the strain measurement accuracy of the high-temperature strain calibration device and provides a reliable technical means for the accurate measurement of high-temperature strain signals.

[0006] A device for improving the strain measurement accuracy of a high-temperature strain calibration device according to an embodiment of the present invention includes:

[0007] a mounting frame, wherein a portion of the mounting frame is placed in a high-temperature furnace, a calibration beam is connected to the mounting frame and is located in the high-temperature furnace, and the calibration beam is spaced apart from the mounting frame in a height direction of the mounting frame;

[0008] A mechanical strain measurement assembly, the mechanical strain measurement assembly comprising a feeler rod assembly, a measuring base assembly and a grating scale assembly, the measuring base assembly comprising a measuring base body, the measuring base body being connected to the mounting frame, the feeler rod assembly comprising a feeler rod and a wing plate, the first end of the feeler rod sequentially passing through the measuring base body, the wing plate and the mounting frame and abutting against the calibration beam, the wing plate being fixedly connected to the measuring base body, the grating scale assembly comprising a grating scale frame and a grating scale, the grating scale frame being connected to the mounting frame, the first end of the grating scale being connected to the wing plate, the feeler rod assembly and the grating scale assembly both being multiple, the multiple feeler rod assemblies being spaced apart along the length direction of the mounting frame, and the multiple feeler rod assemblies corresponding one-to-one to the multiple grating scale assemblies;

[0009] A loading assembly includes a loading portion, a first end of which passes through the mounting frame and is connected to the calibration beam, and the loading assembly is used to apply a loading force to the calibration beam so that the calibration beam deforms toward the touch rod.

[0010] The device for improving the strain measurement accuracy of a high-temperature strain calibration device, according to embodiments of the present invention, places some mechanical strain measurement components outside a high-temperature furnace, reducing the impact of thermal deformation of the feeler rod on measurement results and improving measurement accuracy. Deflection is measured using a grating scale outside the furnace, employing a non-contact measurement method, improving measurement resolution and accuracy. Furthermore, the device is suitable for high-temperature environments, enabling the overall device to achieve accurate strain measurement even in these conditions.

[0011] In some embodiments, the touch rod assembly further includes an elastic member, which is located between the wing plate and the measuring seat body in the height direction of the mounting frame, and the first end of the elastic member abuts against the wing plate, and the second end of the elastic member abuts against the measuring seat body.

[0012] In some embodiments, the measuring seat assembly further includes a guide post, a first end of the guide post is connected to the measuring seat body, and a second end of the guide post is arranged through the wing plate.

[0013] In some embodiments, there are multiple guide posts, and the multiple guide posts are relatively arranged on both sides of the touch rod in the width direction of the mounting frame.

[0014] In some embodiments, the mechanical strain measurement assembly further includes a first linear bearing and a second linear bearing, wherein the first linear bearing is sleeved on the touch rod and connected to the measuring seat body, and the second linear bearing is sleeved on the guide column and connected to the wing plate.

[0015] In some embodiments, the first linear bearing and the second linear bearing are spaced apart in the height direction of the mounting frame.

[0016] In some embodiments, the grating scale assembly further includes a nylon sleeve, which is sleeved on the grating scale. A mounting hole is provided on the grating scale frame, and at least a portion of the nylon sleeve fits in the mounting hole.

[0017] The method for improving the strain measurement accuracy of a high-temperature strain calibration device according to an embodiment of the present invention is accomplished using the device for improving the strain measurement accuracy of a high-temperature strain calibration device according to any one of the above embodiments, and includes the following steps:

[0018] Adjust the installation position of the mechanical strain measurement assembly so that three feeler rods are spaced apart along the length of the calibration beam, and the upper ends of the feeler rods abut against the lower surface of the calibration beam.

[0019] Adjust the installation position of the grating ruler and the adjusting rod so that the top of the grating ruler contacts the wing plate;

[0020] Applying a loading force to the calibration beam to cause the calibration beam to bend toward the touch rod;

[0021] The contact points between the ends of the three feelers and the calibration beam are marked as A, B, and C, and the deflection values ​​ω of the top contact points of the three feelers are obtained respectively. A 、ω B 、ω C , where ω B is the deflection value of the middle touch rod among the three touch rods. The average deflection value of measuring points A and C is taken and the difference between it and the deflection value of measuring point B is used to obtain p, that is,

[0022] Calculate the strain ε based on the three measuring points, that is Where h is the thickness of the calibration beam, p is the deflection difference, and d is the distance between two adjacent measuring points.

[0023] In some embodiments, distances between two adjacent feeler rods in the length direction of the calibration beam are equal.

[0024] In some embodiments, adjusting the installation position of the grating scale and the adjustment rod further includes the following steps: adjusting the compression amount of the grating scale to between one third and two thirds of the total range. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the three-dimensional structure of a device for improving the strain measurement accuracy of a high-temperature strain calibration device according to an embodiment of the present invention.

[0026] Figure 2 It is a schematic cross-sectional structural diagram of a device for improving the strain measurement accuracy of a high-temperature strain calibration device according to an embodiment of the present invention.

[0027] Figure 3 yes Figure 2 An enlarged schematic diagram of A is shown in FIG.

[0028] Figure 4 It is a partial structural schematic diagram of a device for improving the strain measurement accuracy of a high-temperature strain calibration device according to an embodiment of the present invention.

[0029] Figure 5 3. It is a schematic diagram of the use state of the device for improving the strain measurement accuracy of a high-temperature strain calibration device according to an embodiment of the present invention.

[0030] Figure 6 This is a schematic diagram of some parameters of a calibration beam in a method for improving the strain measurement accuracy of a high-temperature strain calibration device according to an embodiment of the present invention.

[0031] Figure 7 This is a schematic diagram of some parameters of a calibration beam in a method for improving the strain measurement accuracy of a high-temperature strain calibration device according to an embodiment of the present invention.

[0032] Figure 8 This is a schematic diagram of some parameters of a calibration beam in a method for improving the strain measurement accuracy of a high-temperature strain calibration device according to an embodiment of the present invention.

[0033] Reference numerals:

[0034] 100, calibration beam, 200, high temperature furnace,

[0035] 1. Install the frame, 11. Install the base, 12. Support legs, 13. Install the base,

[0036] 2. Mechanical strain measurement components,

[0037] 21. Touch rod assembly, 211. Touch rod, 212. Wing plate, 213. Elastic member, 214. Limiting ring,

[0038] 22. Measuring seat assembly, 221. Measuring seat body, 222. Guide column,

[0039] 23. Grating scale assembly, 231. Grating scale frame, 232. Grating scale, 233. Nylon sleeve, 234. Adjustment rod,

[0040] 31. First linear bearing, 32. Second linear bearing,

[0041] 4. Loading component, 41. Loading unit. DETAILED DESCRIPTION

[0042] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0043] The following describes a device for improving the strain measurement accuracy of a high-temperature strain calibration device according to an embodiment of the present invention with reference to the accompanying drawings.

[0044] like Figure 1-Figure 5 As shown, the device for improving the strain measurement accuracy of a high-temperature strain calibration device according to an embodiment of the present invention includes: a mounting frame 1 , a mechanical strain measurement component 2 and a loading component 4 .

[0045] The mounting frame 1 is partially placed in the high temperature furnace 200, and the calibration beam 100 is connected to the mounting frame 1 and is located in the high temperature furnace 200. Figure 1 In the vertical direction), the calibration beam 100 is spaced apart from the mounting frame 1. Specifically, as Figure 1-Figure 5 As shown, the mounting frame 1 includes a mounting base 11, support legs 12, and a mounting base 13. The mounting base 13 is fixedly mounted inside the high-temperature furnace 200. The upper ends of the support legs 12 are connected to the mounting base 13, and the lower ends of the support legs 12 are connected to the mounting base 11 and are located outside the high-temperature furnace 200. Preferably, the upper surface of the mounting base 13 is provided with a plurality of protrusions, and the plurality of protrusions are respectively located at the left and right ends of the mounting base 13 to support the calibration beam 100. This also ensures a certain gap between the calibration beam 100 and the mounting base 13, facilitating the subsequent loading operation of the loading assembly 4.

[0046] It is understandable that the calibration beam 100 is placed above the mounting base 13 and spaced apart from the mounting base 13, so that the deformation of the calibration beam 100 can be independent of the deformation of the mounting frame 1, thereby reducing the impact of the overall deformation of the support mechanism on the measurement results.

[0047] The mechanical strain measurement component 2 includes a feeler rod assembly 21, a measuring seat assembly 22 and a grating scale assembly 23. The measuring seat assembly 22 includes a measuring seat body 221, which is connected to the mounting frame 1. The feeler rod assembly 21 includes a feeler rod 211 and a wing plate 212. The first end of the feeler rod 211 passes through the measuring seat body 221, the wing plate 212 and the mounting frame 1 in sequence and abuts against the calibration beam 100. The wing plate 212 is fixedly connected to the measuring seat body 221. The grating scale assembly 23 includes a grating scale frame 231 and a grating scale 232. The grating scale frame 231 is connected to the mounting frame 1, and the first end of the grating scale 232 is connected to the wing plate 212. There are multiple feeler rod assemblies 21 and grating scale assemblies 23. Multiple feeler rod assemblies 21 are arranged along the length direction of the mounting frame 1 (such as Figure 1 The plurality of touch rod assemblies 21 correspond to the plurality of grating scale assemblies 23 one by one.

[0048] Specifically, if Figure 1-Figure 5 As shown, the measuring base body 221 can be fixedly connected to the mounting frame 1 via screws, bolts, etc. The wing plate 212 is located above the measuring base body 221. The lower end of the feeler rod 211 is connected to the measuring base body 221 and is movable relative to the measuring base body 221. The upper end of the feeler rod 211 passes through the wing plate 212 and the mounting base 13, abutting against the lower surface of the calibration beam 100. The wing plate 212 is fixedly connected to the feeler rod 211 and can move with the movement of the feeler rod 211. The grating scale frame 231 is fixedly connected to the mounting frame 1 via screws, bolts, etc. The grating scale frame 231 provides a mounting position for the grating scale 232. The upper end of the grating scale 232 is connected to the wing plate 212, so that the movement of the feeler rod 211 drives the wing plate 212, which in turn causes the wing plate 212 to act on the grating scale 232, thereby achieving deflection monitoring.

[0049] It can be understood that the combined design of the feeler rod assembly 21 and the grating scale assembly 23 effectively measures the deflection of the calibration beam 100 without being affected by thermal deformation of the feeler rod 211 or deformation of the supporting structure. The feeler rod assembly 21 directly measures the deformation of the calibration beam 100 through contact between the feeler rod 211 and the calibration beam 100, thus eliminating the influence of thermal deformation of the feeler rod 211 on the measurement results. The grating scale assembly 23 measures the displacement of the feeler rod 211 through the grating scale 232, achieving high-precision deflection measurement.

[0050] The loading assembly 4 includes a loading portion 41 , a first end of which passes through the mounting frame 1 and is connected to the calibration beam 100 . The loading assembly 4 is used to apply a loading force to the calibration beam 100 to deform the calibration beam 100 toward the touch rod 211 .

[0051] It is understandable that if Figure 1-Figure 5As shown, the upper end of the loading part 41 passes through the mounting base 13 and is fixedly connected to the calibration beam 100, so that when the loading assembly 4 is started, it can control the loading part 41 to move downward, thereby applying a downward pulling force to the calibration beam 100, causing the calibration beam 100 to bend downward, thereby pushing the touch rod 211 to move downward, and then using the grating scale 232 to monitor the movement of the touch rod 211 to achieve deflection measurement.

[0052] Preferably, if Figure 1-Figure 5 As shown, the plurality of touch rods 211 are located in the middle of the calibration beam 100 , and the loading portion 41 is located on the left and right sides of the touch rod 211 to prevent interference during the application of loading force and affect the measurement results.

[0053] That is, the device for improving the strain measurement accuracy of a high-temperature strain calibration device according to the embodiment of the present invention achieves accurate transmission of the deflection of the calibration beam 100 to the grating scale 232 by placing part of the mechanical strain measurement component 2 outside the high-temperature furnace 200, thereby solving the problem that the grating scale 232 cannot withstand high temperatures. Figure 1 As shown, by arranging three groups of feeler rod assemblies 21 and grating scale assemblies 23 at even intervals in the left-right direction, the deflection difference of the calibration beam 100 can be obtained through the deflection values ​​of the measuring points at the ends of multiple feeler rods, and then the mechanical strain of the calibration beam 100 can be calculated. This can not only offset the vertical displacement of the calibration beam 100 caused by the mechanical load and thermal expansion of the mounting frame 1, but also offset the deflection measurement deviation caused by the thermal expansion of the feeler rod 211, so that the overall device can achieve accurate strain measurement at high temperatures.

[0054] In some embodiments, the touch rod assembly 21 further includes an elastic member 213. In the height direction of the mounting frame 1, the elastic member 213 is located between the wing plate 212 and the measuring seat body 221, and the first end of the elastic member 213 is against the wing plate 212, and the second end of the elastic member 213 is against the measuring seat body 221.

[0055] Specifically, if Figure 1-Figure 5 As shown, the upper end of the elastic member 213 abuts against the wing plate 212, while the lower end of the elastic member 213 abuts against the measuring body. Specifically, when the feeler rod 211 moves downward and drives the wing plate 212 to move, the elastic member 213 compresses and deforms under the pressure of the wing plate 212. This compression of the elastic member 213 exerts upward pressure on the wing plate 212, ensuring that the feeler rod 211 maintains contact with the lower surface of the calibration beam 100, thereby improving measurement accuracy.

[0056] It is understood that during the commissioning phase, the fixed position between the feeler rod 211 and the wing plate 212 can be adjusted so that the upper end of the feeler rod 211 contacts the calibration beam 100 and the elastic member 213 is in a compressed state. In other words, during the commissioning phase, when the upper end of the feeler rod 211 contacts the calibration beam 100, the elastic member 213 is in a compressed state. Specifically, the elastic force of the elastic member 213 acting on the wing plate 212 offsets the weight of the feeler rod 211 and the wing plate 212, allowing the feeler rod 211 to maintain contact with the calibration beam 100 under the elastic force of the elastic member 213. This allows the feeler rod 211 to accurately track the deformation of the calibration beam 100 in real time, ensuring accurate deflection measurement.

[0057] It should be noted that the elastic member 213 may be a spring, a rubber pad or other elements with appropriate elastic properties. Preferably, the elastic member 213 may be a coil spring to facilitate sleeve installation on the touch rod 211 .

[0058] Optionally, the touch rod assembly 21 further includes a limiting ring 214, which is sleeved on the touch rod 211 and located below the elastic member 213 to limit the movement of the elastic member 213 and prevent the elastic member 213 from being severely deformed due to excessive pressure.

[0059] In some embodiments, the measuring seat assembly 22 further includes a guide post 222 , a first end of the guide post 222 is connected to the measuring seat body 221 , and a second end of the guide post 222 is arranged through the wing plate 212 .

[0060] Specifically, if Figure 1-Figure 5 As shown, the lower end of the guide column 222 can be connected to the measuring body by threaded connection, plug-in connection, etc., and the upper end of the guide column 222 passes through the wing plate 212 so that the wing plate 212 can move relative to the guide column 222.

[0061] As can be appreciated, the addition of guide posts 222 enhances the structural stability of the measuring base assembly 22, preventing unwanted displacement of the measuring base body 221 under high temperatures or external forces. Guide posts 222 help maintain alignment between the sensing rod 211 and the calibration beam 100, ensuring that the sensing rod 211 can accurately measure changes in the deflection of the calibration beam 100. Guide posts 222 also limit lateral and longitudinal movement of the measuring base body 221, reducing measurement errors caused by such movement.

[0062] Thus, the guide post 222 provides a stable path, so that the feeler rod 211 maintains linear motion during the measurement process, avoiding possible offset or deviation, thereby improving measurement accuracy.

[0063] Preferably, there are multiple guide posts 222, and the multiple guide posts 222 are arranged in the width direction of the mounting frame 1 (eg Figure 1The touch rod 211 is relatively arranged on both sides of the touch rod 211 in the front-to-back direction.

[0064] Specifically, if Figure 1-Figure 5 As shown, taking two guide posts 222 as an example, the two guide posts 222 are respectively arranged on the front and rear sides of the touch rod 211. Preferably, the positions of the guide posts 222 relative to the touch rod 211 can be mirror-symmetrical to ensure the balance and stability of the structure.

[0065] As can be appreciated, the even distribution of multiple guide posts 222 improves the overall balance of the measuring base assembly 22 and reduces structural tilt or deformation caused by unilateral pressure or temperature fluctuations. The guide posts 222 on both sides work together to provide more precise guidance, ensuring that the vertical movement of the feeler rod 211 is not affected by lateral deviation, thereby maintaining measurement accuracy. The design of multiple guide posts 222 helps improve the torsional resistance of the entire measuring base assembly 22, which is crucial for preventing distortion caused by external forces such as wind loads and vibration.

[0066] In some embodiments, the mechanical strain measurement assembly 2 also includes a first linear bearing 31 and a second linear bearing 32. The first linear bearing 31 is mounted on the touch rod 211 and is connected to the measuring seat body 221. The second linear bearing 32 is mounted on the guide column 222 and is connected to the wing plate 212.

[0067] Specifically, if Figure 1-Figure 5 As shown, the first linear bearing 31 is mounted on the sensing rod 211, and its outer wall is connected to the measuring base body 221. This allows the sensing rod 211 to slide freely within the first linear bearing 31 while maintaining linear motion (up and down). Similarly, the second linear bearing 32 is mounted on the guide post 222, and its outer wall is connected to the wing plate 212, allowing the wing plate 212 to maintain synchronous motion with the sensing rod 211 relative to the guide post 222.

[0068] As can be understood, the use of linear bearings significantly reduces friction between the feeler rod 211 and the measuring base body 221, and between the wing plate 212 and the guide post 222. This allows for smoother movement of the feeler rod 211 and reduces measurement errors caused by friction. Linear bearings ensure linear motion of the feeler rod 211 and wing plate 212, preventing lateral offset or distortion and improving measurement accuracy. The addition of linear bearings also enhances the stability of the feeler rod 211 and wing plate 212 in high-temperature environments, maintaining excellent motion characteristics even under vibration and shock loads.

[0069] Preferably, the grating scale assembly 23 further includes an adjusting rod 234 , which is connected to the wing plate 212 by a threaded connection, and the lower end of the adjusting rod 234 contacts the contact of the grating scale 232 .

[0070] That is to say, since the end of the wing plate 212 contacts the contact of the grating scale 232 through the adjusting rod 234, the contact of the grating scale 232 is compressed when the calibration beam 100 is deformed, and therefore the contact of the grating scale 232 will apply a bending moment to the wing plate 212. In order to offset the influence of the bending moment on the positioning of the wing plate 212, two sets of linear bearings are designed at symmetrical positions on both sides of the contact rod 211 of the wing plate 212 so that the wing plate 212 can maintain a horizontal positioning.

[0071] In some embodiments, in the height direction of the mounting frame 1 , the first linear bearing 31 and the second linear bearing 32 are arranged at intervals.

[0072] It is understandable that if Figure 1-Figure 5 As shown, the second linear bearing 32 is arranged flush in the front-to-back direction, and the first linear bearing 31 is located below the second linear bearing 32 in the height direction. As a result, the three linear bearings present a triangular positional relationship, which can reliably and accurately constrain the touch rod 211, so that the touch rod 211 maintains a vertical movement direction, avoiding deformation transmission errors caused by deflection of the touch rod 211.

[0073] In some embodiments, the grating scale assembly 23 further includes a nylon sleeve 233 , which is mounted on the grating scale 232 . A mounting hole is provided on the grating scale frame 231 , and at least a portion of the nylon sleeve 233 fits in the mounting hole.

[0074] Specifically, if Figure 1-Figure 5 As shown, the nylon sleeve 233 is mounted on the scale 232 to protect and secure the scale 232. Specifically, the scale frame 231 is provided with a mounting hole, and at least a portion of the nylon sleeve 233 fits within the mounting hole. This allows the scale 232 to be secured to the scale frame 231, while the nylon sleeve 233 protects the scale 232 from direct contact.

[0075] It is understood that the cross-sectional profile of nylon sleeve 233 is C-shaped, i.e., nylon sleeve 233 is provided with a through slot. When nylon sleeve 233 is tightened in the mounting hole, the through slot is compressed, thereby achieving the purpose of clamping grating scale 232. Furthermore, by adjusting the constant clamping force so that the friction force is slightly greater than the spring force of the contact of grating scale 232, the clamping force can ensure that grating scale 232 is stationary during operation within the normal measuring range. In the event of excessive pressure in an unexpected situation, grating scale 232 will be pushed, making it easier to adjust the coaxiality and protecting the sensor.

[0076] The following describes a method for improving the strain measurement accuracy of a high-temperature strain calibration device according to an embodiment of the present invention.

[0077] like Figures 1-8 As shown, the method for improving the strain measurement accuracy of a high-temperature strain calibration device according to an embodiment of the present invention is accomplished by using the device for improving the strain measurement accuracy of a high-temperature strain calibration device according to any one of the above embodiments, and is characterized by comprising the following steps:

[0078] Adjust the installation position of the mechanical strain measurement assembly, arrange three feelers at intervals along the length of the calibration beam, and make the upper ends of the feelers contact the lower surface of the calibration beam. Figure 1-Figure 5 As shown, three feeler rods are spaced apart in the left-right direction, ensuring they cover the equal strain area of ​​the calibration beam. The upper ends of the feeler rods abut against the lower surface of the calibration beam. When the calibration beam bends, the feeler rods directly sense the change in deflection.

[0079] Adjust the mounting position of the scale and the adjustment rod so that the top of the scale contacts the adjustment rod. It is understood that the top of the scale contacts the adjustment rod. The blade moves with the movement of the feeler rod, and the scale measures the deflection change of the calibration beam by sensing the displacement of the blade.

[0080] Ensure that the contact between the grating scale and the wing plate is tight and stable so as to accurately record and transmit the displacement signal.

[0081] A loading force is applied to the calibration beam, causing it to bend toward the stem. It should be understood that the loading assembly applies the loading force to the calibration beam, causing it to bend toward the stem. The magnitude of the loading force should be determined based on the material properties of the calibration beam and the expected strain range. The loading force should be applied evenly and symmetrically to ensure uniform deformation of the calibration beam under load, forming a region of equal strain.

[0082] The contact points between the ends of the three feelers and the calibration beam are marked as A, B, and C, and the deflection values ​​ω of the top contact points of the three feelers are obtained respectively. A 、ω B 、ω C , where ω B is the deflection value of the middle touch rod among the three touch rods. The average deflection value of measuring points A and C is taken and the difference between it and the deflection value of measuring point B is used to obtain p, that is,

[0083] Calculate the strain ε based on the three measuring points, that is Where h is the thickness of the calibration beam, p is the deflection difference, and d is the distance between two adjacent measuring points.

[0084] It should be noted that the calculation of the above strain also includes the following steps:

[0085] like Figure 6-Figure 8 As shown in the figure, according to the basic theory of beam bending deformation, the length of the neutral layer is l, and the length of the lower surface of the beam after stretching is l', then:

[0086] l = ρθ, formula 1;

[0087]

[0088] According to the definition of strain:

[0089]

[0090] Substituting the above formula 1 and formula 2 into the above formula, the three-point lateral strain calculation formula is obtained as follows:

[0091]

[0092] In addition, it should be noted that when in use, the mechanical strain to be loaded is often used as the target value. When loading, the deflection difference calculated based on the mechanical strain is used as the loading target. The calculation method is as follows:

[0093] According to the strain calculation formula 3, we can get:

[0094] εp 2 -hp+εd 2 =0

[0095] List the coefficients of a quadratic equation:

[0096]

[0097] Apply the quadratic equation root-finding formula:

[0098]

[0099] According to the actual situation during strain loading, when the calibration beam is bent, p should be a finite positive value, and when it approaches 0, the p value also approaches zero. Therefore, the negative solution satisfies this condition, that is:

[0100]

[0101] In some embodiments, the distance between adjacent sensor pins along the length of the calibration beam is equal. It is understood that this equal distance between adjacent sensor pins ensures a uniform distribution of the sensor pins along the length. This uniform distribution of sensor pins can detect unbalanced loading caused by misalignment in the loading mechanism or calibration beam assembly. A significant deviation in the deflection values ​​measured between the sensor pins on either side indicates unbalanced loading. This indicates that the calibration beam is no longer in a state of equal strain between the two loading positions. The loading mechanism and calibration beam should be inspected and reinstalled.

[0102] The core of this calculation scheme is to calculate the mechanical strain of the calibration beam's strain-strained sections by taking the difference between the deflections at the beam's midpoint and on either side. Using the deflection difference to calculate the calibration beam's mechanical strain has two advantages: First, when the calibration beam is loaded, the deformation of the mounting frame causes an overall upward or downward displacement of the calibration beam, which is included in the measured deflection. The deflection difference offsets this overall displacement, making the calculated mechanical strain more accurate. Second, because the mounting base, the feeler rod, and the support legs are located in a high-temperature furnace, lateral thermal expansion of the mounting base with temperature fluctuations causes changes in the distance between the calibration beam's support points. Thermal expansion of the support legs also causes an overall upward or downward displacement of the calibration beam. Thermal expansion of the feeler rod directly affects the deflection measurement. When calculating the calibration beam's mechanical strain based on Equation 3, the support distance is not included in the calculation. Thermal deformation of the feeler rod and support legs is offset by the deflection difference, making the calculated mechanical strain more accurate.

[0103] In some embodiments, adjusting the installation position of the scale and the adjustment rod further includes the following steps: adjusting the compression of the scale to between one-third and two-thirds of the scale's total range. It is understood that when installing the scale, its initial compression needs to be adjusted based on the scale's total range (i.e., the maximum displacement range the scale can measure). The goal is to set the scale's compression to between one-third and two-thirds of its total range.

[0104] That is, a scale typically exhibits optimal linearity in the middle of its total range. Adjusting the compression within this range ensures high scale linearity during measurement, thereby improving strain measurement accuracy. If the scale's compression is too small, it may not fully utilize its measuring range, limiting the measurement dynamic range. If the compression is too large, it may overload the scale, affecting its long-term performance and measurement accuracy. Adjusting the compression in the middle of its total range can avoid both of these situations.

[0105] It should be noted that the calibration beam was preloaded with a maximum strain slightly higher than that in the formal test, 10%. After the target strain was applied, unloading was completed within 15 seconds to check whether the feeler rod could move along with the deformation of the calibration beam, especially whether the feeler rod moved smoothly during unloading and whether there was any sticking.

[0106] After confirmation, start the equipment. The equipment applies deformation to the calibration beam to generate mechanical strain on the calibration beam. The strain value is calculated by the deflection difference between the center grating scale and the average value of the grating scales on both sides.

[0107] 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", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations 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 should not be understood as limiting the present invention.

[0108] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0109] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0110] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0111] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" mean that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction.

[0112] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A device for improving the strain measurement accuracy of a high-temperature strain calibration device, characterized in that: include: a mounting frame, wherein a portion of the mounting frame is placed in a high-temperature furnace, a calibration beam is connected to the mounting frame and is located in the high-temperature furnace, and the calibration beam is spaced apart from the mounting frame in a height direction of the mounting frame; A mechanical strain measurement assembly, the mechanical strain measurement assembly comprising a feeler rod assembly, a measuring base assembly and a grating scale assembly, the measuring base assembly comprising a measuring base body, the measuring base body being connected to the mounting frame, the feeler rod assembly comprising a feeler rod and a wing plate, the first end of the feeler rod sequentially passing through the measuring base body, the wing plate and the mounting frame and abutting against the calibration beam, the wing plate being fixedly connected to the measuring base body, the grating scale assembly comprising a grating scale frame and a grating scale, the grating scale frame being connected to the mounting frame, the first end of the grating scale being connected to the wing plate, the feeler rod assembly and the grating scale assembly both being multiple, the multiple feeler rod assemblies being spaced apart along the length direction of the mounting frame, and the multiple feeler rod assemblies corresponding one-to-one to the multiple grating scale assemblies; A loading assembly includes a loading portion, a first end of which passes through the mounting frame and is connected to the calibration beam, and the loading assembly is used to apply a loading force to the calibration beam so that the calibration beam deforms toward the touch rod.

2. The device for improving the strain measurement accuracy of a high-temperature strain calibration device according to claim 1, characterized in that: The touch rod assembly also includes an elastic member. In the height direction of the mounting frame, the elastic member is located between the wing plate and the measuring seat body, and the first end of the elastic member abuts against the wing plate, and the second end of the elastic member abuts against the measuring seat body.

3. The device for improving the strain measurement accuracy of a high-temperature strain calibration device according to claim 2, characterized in that: The measuring seat assembly further includes a guide post, a first end of which is connected to the measuring seat body, and a second end of which is arranged to pass through the wing plate.

4. The device for improving the strain measurement accuracy of a high-temperature strain calibration device according to claim 3, characterized in that: There are a plurality of guide posts, which are arranged oppositely on both sides of the touch rod in the width direction of the mounting frame.

5. The device for improving the strain measurement accuracy of a high-temperature strain calibration device according to claim 4, characterized in that: The mechanical strain measurement assembly also includes a first linear bearing and a second linear bearing, the first linear bearing is sleeved on the touch rod and connected to the measuring seat body, the second linear bearing is sleeved on the guide column and connected to the wing plate.

6. The device for improving the strain measurement accuracy of a high-temperature strain calibration device according to claim 5, characterized in that: In the height direction of the mounting frame, the first linear bearing and the second linear bearing are arranged at intervals.

7. The device for improving the strain measurement accuracy of a high-temperature strain calibration device according to claim 6, characterized in that: The grating scale assembly also includes a nylon sleeve, which is sleeved on the grating scale. The grating scale frame is provided with a mounting hole, and at least a portion of the nylon sleeve is fitted in the mounting hole.

8. A method for improving the strain measurement accuracy of a high-temperature strain calibration device, wherein the method is accomplished by using the device for improving the strain measurement accuracy of a high-temperature strain calibration device according to any one of claims 1 to 7, characterized in that: The following steps are involved: Adjust the installation position of the mechanical strain measurement assembly so that three feeler rods are spaced apart along the length of the calibration beam, and the upper ends of the feeler rods abut against the lower surface of the calibration beam. Adjust the installation position of the grating ruler and the adjusting rod so that the top of the grating ruler contacts the wing plate; Applying a loading force to the calibration beam to cause the calibration beam to bend toward the touch rod; The contact points between the ends of the three feelers and the calibration beam are marked as A, B, and C, and the deflection values ​​ω of the top contact points of the three feelers are obtained respectively. A 、ω B 、ω C , where ω B is the deflection value of the middle touch rod among the three touch rods. The average deflection value of measuring points A and C is taken and the difference between it and the deflection value of measuring point B is used to obtain p, that is, Calculate the strain ε based on the three measuring points, that is Where h is the thickness of the calibration beam, p is the deflection difference, and d is the distance between two adjacent measuring points.

9. The method for improving the strain measurement accuracy of a high-temperature strain calibration device according to claim 8, characterized in that: In the length direction of the calibration beam, the distances between two adjacent touch rods are equal.

10. The method for improving the strain measurement accuracy of a high-temperature strain calibration device according to claim 8, characterized in that: Adjusting the installation position of the grating scale and the adjusting rod also includes the following steps: adjusting the compression amount of the grating scale to between one third and two thirds of the total range.

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