Method and system for calibrating hydraulic torque wrench

Abstract

The invention provides a method and system for calibrating a hydraulic torque wrench, and belongs to the technical field of hydraulic torque wrenches. The method comprises the following steps: sequentially executing calibration programs corresponding to a plurality of preset calibration points to obtain calibration data of each preset calibration point; calculating index values of preset evaluation indexes corresponding to the target hydraulic torque wrench based on the calibration data of the preset calibration points; determining the accuracy grade of the target hydraulic torque wrench based on the index value of each preset evaluation index corresponding to the target hydraulic torque wrench; and according to the calibration data of each preset calibration point, establishing a calibration equation between the torque output value of the target hydraulic torque wrench and the hydraulic pressure value output to the target hydraulic torque wrench by the hydraulic source. The purpose of calculating the torque output value of the target hydraulic torque wrench under any hydraulic pressure value is achieved while the wrench head of the hydraulic torque wrench and the hydraulic pump are calibrated separately.

Description

Technical Field

[0001] The present invention relates to the technical field of hydraulic torque wrenches, and in particular to a method for calibrating a hydraulic torque wrench, a system for calibrating a hydraulic torque wrench, a machine-readable storage medium and an electronic device. Background Art

[0002] The hydraulic torque wrench is a power tool that outputs a set torque in a hydraulically driven manner and is widely used in the disassembly and assembly of fasteners. Its working principle is: the driving force is provided by a hydraulic source, and the various components in the hydraulic torque wrench work together to apply torque to the object to be applied. The torque value applied by the hydraulic torque wrench is indirectly or directly indicated by the indicating system. As a measuring instrument, the hydraulic torque wrench should be traced.

[0003] At present, the calibration of hydraulic torque wrenches is usually limited to the range of "manual pump" and "one wrench with one pump", and it is mandatory to pair the wrench head with the pump. Recalibration is required every time they are replaced, which cannot meet the current application requirements of the "one-to-many" mode (i.e. one pump drives multiple wrenches at the same time).

[0004] During the calibration of the hydraulic torque wrench, the reaction arm of the wrench is usually supported by a block, but this type of structure cannot always keep a close fit with the reaction arm. After each pressure relief, due to the combined influence of gravity, reaction force and other factors, the reaction arm will bounce off the block, which may cause the wrench to become unstable. When the pressure is applied next time, this instability will cause the ratchet structure inside the wrench to impact, affecting the stability of the calibration results and even causing damage to the hydraulic torque wrench.

[0005] Therefore, how to adopt the technical route of "calibration without pump" to allow the wrench and the hydraulic pump to be calibrated separately and realize the calculation of arbitrary torque values ​​and hydraulic pressure values ​​is a problem that needs to be solved urgently. Summary of the invention

[0006] The purpose of the embodiments of the present invention is to provide a method and system for calibrating a hydraulic torque wrench, so as to at least solve the above-mentioned problem of how to adopt the technical route of "calibration without a pump", allowing the wrench head and the hydraulic pump to be calibrated separately, and realizing the calculation of arbitrary torque values ​​and hydraulic pressure values.

[0007] In order to achieve the above object, the present invention provides a method for calibrating a hydraulic torque wrench in a first aspect, comprising: When it is determined that the target hydraulic torque wrench has completed resetting, the calibration programs corresponding to the plurality of preset calibration points are sequentially executed to obtain calibration data of each preset calibration point; wherein the calibration program corresponding to each preset calibration point includes an execution program of the calibration process corresponding to the preset calibration times of each preset calibration point, and the calibration data of each preset calibration point includes the hydraulic pressure value output to the target hydraulic torque wrench by the hydraulic source corresponding to each preset calibration point in each calibration process and the torque output value of the target hydraulic torque wrench; Based on the calibration data of each preset calibration point, the index value of each preset evaluation index corresponding to the target hydraulic torque wrench is calculated; Determining the accuracy level of the target hydraulic torque wrench based on the indicator values ​​of each preset evaluation indicator corresponding to the target hydraulic torque wrench; When the accuracy level of the target hydraulic torque wrench reaches the preset qualified level, a calibration equation between the torque output value of the target hydraulic torque wrench and the hydraulic pressure value output by the hydraulic source to the target hydraulic torque wrench is established according to the calibration data of each preset calibration point; wherein the calibration equation is used to calculate the torque output value of the target hydraulic torque wrench at any hydraulic pressure value.

[0008] Optionally, the steps of the calibration process for any preset calibration point include: After the control calibrator performs zero point calibration and controls the hydraulic source to start, it is determined whether the target hydraulic torque wrench is in a normal operating state; When it is determined that the target hydraulic torque wrench is in a normal operating state, the hydraulic source is controlled to output a hydraulic pressure matching a preset calibration point to the target hydraulic torque wrench, and the hydraulic source pressure indication and the calibrator indication are recorded, and the hydraulic source pressure indication and the calibrator indication are used as calibration data of the preset calibration point in this calibration process; wherein the calibrator indication represents the torque output value of the target hydraulic torque wrench, and the hydraulic source pressure indication represents the hydraulic pressure value output by the hydraulic source to the target hydraulic torque wrench.

[0009] Optionally, the establishment rules of the above calibration equation include: The hydraulic pressure value output from the hydraulic source to the target hydraulic torque wrench is used as the independent variable, and the torque output value of the target hydraulic torque wrench is used as the dependent variable. The least square method is used to establish the calibration equation; where, The calibration equation is: ;in, , , y represents the torque output value of the target hydraulic torque wrench, a represents the slope of the calibration equation, x represents the hydraulic pressure value output from the hydraulic source to the target hydraulic torque wrench, b represents the intercept of the calibration equation, and x i represents the hydraulic pressure value of the i-th preset calibration point, Represents the arithmetic mean of the hydraulic pressure values ​​of all preset calibration points, yi represents the torque output value of the target hydraulic torque wrench at the i-th preset calibration point, It represents the arithmetic mean of the torque output values ​​of the target hydraulic torque wrench of all preset calibration points, and n represents the number of preset calibration points.

[0010] Optionally, the above-mentioned preset evaluation index includes indication repeatability; The calibration data based on the preset calibration points are used to calculate the index values ​​of the preset evaluation indexes corresponding to the target hydraulic torque wrench, including: According to the indication repeatability calculation formula, calculate the indication repeatability index value corresponding to the target hydraulic torque wrench; The calculation formula for the repeatability of indication includes: , The index value representing the repeatability of the indication of the target hydraulic torque wrench corresponding to the i-th preset calibration point, Indicates the maximum value of the calibration instrument indication corresponding to the i-th preset calibration point, Indicates the minimum value of the calibration instrument indication corresponding to the i-th preset calibration point, Represents the arithmetic mean of the calibrator indications corresponding to the i-th preset calibration point.

[0011] Optionally, the above-mentioned preset evaluation index includes linear error; The calibration data based on the preset calibration points are used to calculate the index values ​​of the preset evaluation indexes corresponding to the target hydraulic torque wrench, including: According to the linear error calculation formula, calculate the index value of the linear error corresponding to the target hydraulic torque wrench; Among them, the linear error calculation formula includes , , Δξ j The residual of the jth preset calibration point represents the difference between the measured value and the fitted value of the torque output value of the jth preset calibration point. j Represents the arithmetic mean of the torque output values ​​at the jth preset calibration point, T ej represents the fitting value of the torque output value of the jth preset calibration point, ξ represents the index value of the linear error of the target hydraulic torque wrench, T eF.S represents the fitting value of the torque output value of the target hydraulic torque wrench corresponding to the rated pressure of the target hydraulic torque wrench, Δξ max Indicates the maximum value among the residuals of each preset calibration point.

[0012] Optionally, the above-mentioned preset evaluation index includes interpolation error; The calibration data based on the preset calibration points are used to calculate the index values ​​of the preset evaluation indexes corresponding to the target hydraulic torque wrench, including: According to the interpolation error calculation formula, calculate the index value of the interpolation error corresponding to the target hydraulic torque wrench; Among them, the interpolation error calculation formula includes , I j The index value of the interpolation error of the jth preset calibration point, T j Represents the arithmetic mean of the torque output values ​​at the jth preset calibration point, T ej Represents the fitted value of the torque output value at the j-th preset calibration point.

[0013] Optionally, the method further includes evaluating the uncertainty of the torque output value of the target hydraulic torque wrench represented by the indication of the calibrator; The uncertainty assessment rules include: Comprehensive uncertainty components introduced by the calibrator indication error u b and the uncertainty component introduced by the repeatability of torque measurement u R , get the uncertainty value corresponding to the torque output value of the target hydraulic torque wrench; where, Uncertainty component introduced by the indication error of the calibrator u b The calculation formula is: ; Uncertainty components introduced by torque measurement repeatability u R The calculation rules include: Based on the measured values ​​of the torque output values ​​at the preset calibration points during each calibration process, the Bessel formula is used Calculate the experimental standard deviation; based on n The uncertainty component introduced by the repeatability of torque measurement is calculated by taking the average value of the torque output value of the calibration process and the test standard deviation. u R ; Among them, the uncertainty component u R The calculation formula is ; The calculation formula for the uncertainty value corresponding to the torque output value of the target hydraulic torque wrench is: ; in, δ Indicates the maximum allowable error of the calibrator indication. represents the calibrator indication corresponding to the i-th calibration process, s represents the test standard deviation, It represents the arithmetic mean of the calibrator indications corresponding to n calibration processes. A numerical value representing the uncertainty of the torque output value of the target hydraulic torque wrench.

[0014] A second aspect of the present invention provides a system for calibrating a hydraulic torque wrench, comprising: A calibration program execution module is used to sequentially execute calibration programs corresponding to a plurality of preset calibration points to obtain calibration data of each preset calibration point when it is determined that the target hydraulic torque wrench has completed resetting; wherein the calibration program corresponding to each preset calibration point includes an execution program of a calibration process corresponding to a preset calibration number of each preset calibration point, and the calibration data of each preset calibration point includes a hydraulic pressure value output to the target hydraulic torque wrench by a hydraulic source corresponding to each preset calibration point in each calibration process and a torque output value of the target hydraulic torque wrench; An index evaluation module, used to calculate the index value of each preset evaluation index corresponding to the target hydraulic torque wrench based on the calibration data of each preset calibration point; An accuracy level determination module, used to determine the accuracy level of the target hydraulic torque wrench based on the index values ​​of each preset evaluation index corresponding to the target hydraulic torque wrench; A calibration equation establishment module is used to establish a calibration equation between the torque output value of the target hydraulic torque wrench and the hydraulic pressure value output by the hydraulic source to the target hydraulic torque wrench according to the calibration data of each preset calibration point when the accuracy level of the target hydraulic torque wrench reaches the preset qualified level; wherein the calibration equation is used to calculate the torque output value of the target hydraulic torque wrench under any hydraulic pressure value.

[0015] In a third aspect of the present invention, a machine-readable storage medium is provided, on which instructions are stored. When the instructions are executed by a processor, the processor is configured to execute the method for calibrating a hydraulic torque wrench.

[0016] In a fourth aspect of the present invention, an electronic device is provided, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the method for calibrating a hydraulic torque wrench when executing the computer program.

[0017] Through the above technical solution, a method and system for calibrating a hydraulic torque wrench is provided. When it is determined that the target hydraulic torque wrench has completed the reset, the calibration procedures corresponding to multiple preset calibration points are sequentially executed to obtain calibration data including the hydraulic pressure value output to the target hydraulic torque wrench by the hydraulic source corresponding to each preset calibration point in each calibration process and the torque output value of the target hydraulic torque wrench. Thus, according to the calibration data of each preset calibration point, the index value of each preset evaluation index corresponding to the target hydraulic torque wrench is calculated, and the index value of each preset evaluation index corresponding to the target hydraulic torque wrench is compared with the accuracy level of the hydraulic wrench to determine the accuracy level of the target hydraulic torque wrench. When the accuracy level of the target hydraulic torque wrench reaches the preset qualified level, according to the calibration data of each preset calibration point, the hydraulic pressure value output to the target hydraulic torque wrench by the hydraulic source is used as the independent variable, and the torque output value of the target hydraulic torque wrench is used as the dependent variable, and a calibration equation is established, so that the torque output value of the target hydraulic torque wrench under any hydraulic pressure value can be calculated according to the calibration equation. This method and system adopt the technical route of "calibration without pump", which can realize the separate calibration of the wrench head and hydraulic pump of the hydraulic torque wrench, and can reliably evaluate the accuracy of the wrench head, thus providing a reliable basis for the wrench head pairing in the "one-to-many" mode. It not only achieves the purpose of calculating the torque output value of the target hydraulic torque wrench under any hydraulic pressure value, but also realizes the automatic calibration of the hydraulic torque wrench. This method and system can be widely used in the calibration of hydraulic torque wrenches in various industries, especially in the "one-to-many" mode of the wind power industry, solving the problem of hydraulic torque wrench pairing in this mode.

[0018] Other features and advantages of the embodiments of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the embodiments of the present invention, but do not constitute a limitation on the embodiments of the present invention. In the accompanying drawings: Figure 1 is a flow chart of a method for calibrating a hydraulic torque wrench provided by one embodiment of the present invention; Figure 2 It is a structural schematic diagram of a hydraulic torque wrench calibration device provided by one embodiment of the present invention; Figure 3 is a block diagram of a system for calibrating a hydraulic torque wrench provided by one embodiment of the present invention; Figure 4 It is a schematic diagram of the structure of an electronic device provided by a preferred embodiment of the present invention.

[0020] Description of Reference Numerals 10 - electronic device, 100 - processor, 101 - memory, 102 - computer program. DETAILED DESCRIPTION

[0021] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0022] Figure 1 FIG. 1 is a flow chart of a method for calibrating a hydraulic torque wrench provided by one embodiment of the present invention. Figure 1 As shown, an embodiment of the present invention provides a method for calibrating a hydraulic torque wrench, comprising: S110: When it is determined that the target hydraulic torque wrench has completed resetting, the calibration programs corresponding to the plurality of preset calibration points are sequentially executed to obtain calibration data of each preset calibration point; wherein the calibration program corresponding to each preset calibration point includes an execution program of a calibration process corresponding to a preset calibration number of each preset calibration point, and the calibration data of each preset calibration point includes a hydraulic pressure value output to the target hydraulic torque wrench by a hydraulic source corresponding to each preset calibration point in each calibration process and a torque output value of the target hydraulic torque wrench; Please refer to Figure 2 , Figure 2It is a structural schematic diagram of a hydraulic torque wrench calibration device provided by an embodiment of the present invention. A hydraulic torque wrench calibration device is mainly composed of a standard pressure sensor, a standard intelligent torque meter, a calibration workbench, a hydraulic source system and a control part. Each measuring point (i.e., a standard pressure sensor, a standard intelligent torque meter, a calibration workbench and a hydraulic source system) can output a corresponding standard signal, collect the measured value through the host computer, and communicate with the host computer. The host computer is a laptop computer, which is connected to the hydraulic station control box through a network cable interface to achieve communication. The printer is used to print the measurement results and the calibration certificate. In addition, the core components meet the following requirements: 1. Standard torque meter: (It should be noted that the standard torque meter in this application is consistent with the calibrator in this application) It can instantly display the applied torque value, and the maximum allowable error of its indication is not greater than 1 / 5 of the maximum allowable error of the calibrated hydraulic wrench (i.e., the target hydraulic torque wrench), and its upper limit of measurement should not be less than 130% of the rated value of the target hydraulic torque wrench. When used to calibrate a three-level hydraulic wrench, the accuracy level of the standard pressure sensor is 0.05, the measurement accuracy is better than ±0.1% FS, and the measurement range is (0~100) MPa; the accuracy level of the standard torque sensor is 0.3, and the resolution is 1 N·m. 2. Hydraulic source: The level of its pressure display instrument should be better than 1 / 4 of the level of the hydraulic source display instrument of the hydraulic torque wrench in use, and when it stabilizes to the preset pressure, the pressure indication fluctuation within 3 consecutive seconds shall not exceed 0.5% of the preset pressure value. 3. Timer: The division value is better than 0.1 s. 4. Calibration workbench: It has a mechanical structure that keeps the hydraulic torque wrench applying a stable torque. At the same time, the calibration workbench is equipped with an anti-instability device. The anti-instability device consists of a guide rail, a column, a crossbeam, a bracket and a thrust component. It can freely adjust the position in the three-dimensional direction to adapt to different types of hydraulic torque wrenches. At the same time, through the tightness of its own spring, the reset force is adjusted to maintain the stable posture of the hydraulic torque wrench and keep the wrench reaction arm and the block tightly fitted.

[0023] Specifically, the specific process of resetting the target hydraulic torque wrench is as follows: (1) The target hydraulic torque wrench is mounted on the machine, and various brackets are adjusted (including front and rear horizontal position adjustment brackets (used to adjust the front and rear positions, corresponding to the different lengths of rotation radii formed by the rotation axis of different models of hydraulic torque wrenches and the force center line of the reaction arm), left and right horizontal position adjustment brackets (used to adjust the horizontal position) and up and down vertical position adjustment brackets (used to adjust the vertical position)) to make the horizontal rotating spring returner fit the target hydraulic torque wrench. (2) Adjust the angle of the horizontal rotating spring returner to try to make the spring return extension line coincide with or be parallel to the tangent of the rotation radius of the target hydraulic torque wrench. (3) Adjust the spring force to ensure a gentle reset action and minimize the impact of the reset shock on the data. (4) Repeat the above steps to achieve automatic reset. After resetting the target hydraulic torque wrench, during the process of pressurizing the target hydraulic torque wrench, the contact area between the reaction arm working surface of the target hydraulic torque wrench and the block of the calibrator should be no less than 2 / 3 of the reaction arm working surface; if it is a hydraulic torque wrench with a fixed connection, the hydraulic torque wrench should be tightly connected to the calibration fixture; and the fit / connection during the pressurization process must be tight and cannot run idle. During the calibration process, keep the reaction arm of the hydraulic torque wrench and the workbench block automatically fit, and the wrench body automatically resets. The reset process is gentle, and the impact generated will not affect the calibration data, reducing the unpredictable risks caused by impact during the equipment reset process, and at the same time avoiding safety hazards caused by personnel working close to the pressurized test equipment.

[0024] In some implementations of the present embodiment, the steps of the calibration process of any preset calibration point include: after controlling the calibrator to perform zero point calibration and controlling the hydraulic source to start, judging whether the target hydraulic torque wrench is in a normal operating state; when it is determined that the target hydraulic torque wrench is in a normal operating state, controlling the hydraulic source to output a hydraulic pressure matching the preset calibration point to the target hydraulic torque wrench, recording the hydraulic source pressure indication and the calibrator indication, and using the hydraulic source pressure indication and the calibrator indication as the calibration data of the preset calibration point in this calibration process; wherein, the calibrator indication represents the torque output value of the target hydraulic torque wrench, and the hydraulic source pressure indication represents the hydraulic pressure value output by the hydraulic source to the target hydraulic torque wrench.

[0025] Specifically, the specific steps of the calibration procedure corresponding to each preset calibration point are as follows: 1. Appearance and performance inspection: The moving parts of the target hydraulic torque wrench should rotate flexibly without sticking. The parts of the target hydraulic torque wrench should not be obviously damaged or deformed. 2. Calibration of torque indication: The preset calibration point is selected from 20% to 80% of the rated pressure of the target hydraulic torque wrench, preferably an integer point; the preset calibration points shall not be less than five points, including the upper and lower limits, and shall be evenly distributed and calibrated point by point. The calibration steps are as follows: adjust the zero point of the calibrator, start the hydraulic source, observe whether the target hydraulic torque wrench operates normally, load the hydraulic source to the preset calibration point, and keep it stable. When it stabilizes to the preset pressure, the pressure indication fluctuation shall not exceed 0.5% of the preset pressure value within 3 consecutive seconds, and record the hydraulic source pressure indication and the calibrator indication. Unload the load. According to this step, repeat the measurement at least 3 times. Complete the calibration of the preset calibration point. Calibrate the other preset calibration points in turn according to the above steps.

[0026] S120: Calculating the index values ​​of each preset evaluation index corresponding to the target hydraulic torque wrench based on the calibration data of each preset calibration point; In some implementations of this embodiment, the above-mentioned preset evaluation index includes indication repeatability; the above-mentioned calibration data based on each preset calibration point, calculates the index value of each preset evaluation index corresponding to the target hydraulic torque wrench, including: according to the indication repeatability calculation formula, calculates the index value of the indication repeatability corresponding to the target hydraulic torque wrench; wherein the indication repeatability calculation formula includes , The index value representing the repeatability of the indication of the target hydraulic torque wrench corresponding to the i-th preset calibration point, Indicates the maximum value of the calibration instrument indication corresponding to the i-th preset calibration point, Indicates the minimum value of the calibration instrument indication corresponding to the i-th preset calibration point, Represents the arithmetic mean of the calibrator indications corresponding to the i-th preset calibration point.

[0027] In some implementations of this embodiment, the above-mentioned preset evaluation index includes a linear error; the above-mentioned calibration data based on each preset calibration point, calculates the index value of each preset evaluation index corresponding to the target hydraulic torque wrench, including: according to the linear error calculation formula, calculates the index value of the linear error corresponding to the target hydraulic torque wrench; wherein the linear error calculation formula includes , , Δξ j The residual of the jth preset calibration point represents the difference between the measured value and the fitted value of the torque output value of the jth preset calibration point. j Represents the arithmetic mean of the torque output values ​​at the jth preset calibration point, T ejrepresents the fitting value of the torque output value of the jth preset calibration point, ξ represents the index value of the linear error of the target hydraulic torque wrench, T eF.S represents the fitting value of the torque output value of the target hydraulic torque wrench corresponding to the rated pressure of the target hydraulic torque wrench, Δξ max Indicates the maximum value among the residuals of each preset calibration point.

[0028] In some implementations of this embodiment, the above-mentioned preset evaluation index includes an interpolation error; the above-mentioned calibration data based on each preset calibration point, calculates the index value of each preset evaluation index corresponding to the target hydraulic torque wrench, including: according to the interpolation error calculation formula, calculates the index value of the interpolation error corresponding to the target hydraulic torque wrench; wherein the interpolation error calculation formula includes , I j The index value of the interpolation error of the jth preset calibration point, T j Represents the arithmetic mean of the torque output values ​​at the jth preset calibration point, T ej Represents the fitted value of the torque output value at the j-th preset calibration point.

[0029] Specifically, the method provides evaluation indicators for evaluating the accuracy of the hydraulic torque wrench, such as indication repeatability, linear error, and interpolation error. By respectively calculating the index value of the indication repeatability corresponding to the target hydraulic torque wrench, the index value of the linear error corresponding to the target hydraulic torque wrench, and the index value of the interpolation error corresponding to the target hydraulic torque wrench, the index value of the evaluation indicator for evaluating the accuracy of the target hydraulic torque wrench can be obtained.

[0030] S130: determining the accuracy level of the target hydraulic torque wrench based on the indicator values ​​of each preset evaluation indicator corresponding to the target hydraulic torque wrench; Specifically, the index values ​​of each preset evaluation index corresponding to the target hydraulic torque wrench are compared with the accuracy level of the hydraulic wrench to determine the accuracy level of the target hydraulic torque wrench. The accuracy level and technical indicators of the hydraulic wrench are shown in Table 1: Table 1 Accuracy level and technical indicators of hydraulic wrenches

[0031] S140: When the accuracy level of the target hydraulic torque wrench reaches the preset qualified level, a calibration equation is established between the torque output value of the target hydraulic torque wrench and the hydraulic pressure value output from the hydraulic source to the target hydraulic torque wrench according to the calibration data of each preset calibration point; wherein the calibration equation is used to calculate the torque output value of the target hydraulic torque wrench at any hydraulic pressure value.

[0032] Specifically, the method sequentially executes calibration procedures corresponding to a plurality of preset calibration points when determining that the target hydraulic torque wrench has completed resetting, and obtains calibration data including the hydraulic pressure value output from the hydraulic source to the target hydraulic torque wrench and the torque output value of the target hydraulic torque wrench corresponding to each preset calibration point in each calibration process. Thus, according to the calibration data of each preset calibration point, the index value of each preset evaluation index corresponding to the target hydraulic torque wrench is calculated, and the index value of each preset evaluation index corresponding to the target hydraulic torque wrench is compared with the accuracy level of the hydraulic wrench, so as to determine the accuracy level of the target hydraulic torque wrench. When the accuracy level of the target hydraulic torque wrench reaches the preset qualified level, according to the calibration data of each preset calibration point, the hydraulic pressure value output from the hydraulic source to the target hydraulic torque wrench is used as the independent variable, and the torque output value of the target hydraulic torque wrench is used as the dependent variable, and a calibration equation is established, so that the torque output value of the target hydraulic torque wrench under any hydraulic pressure value can be calculated according to the calibration equation. This method adopts the technical route of "calibration without pump", which can realize the separate calibration of the hydraulic torque wrench head and the hydraulic pump, and can reliably evaluate the accuracy of the wrench head, thus providing a reliable basis for the pairing of wrenches in the "one-to-many" mode. It not only achieves the purpose of calculating the torque output value of the target hydraulic torque wrench under any hydraulic pressure value, but also realizes the automatic calibration of the hydraulic torque wrench. This method can be widely used in the calibration of hydraulic torque wrenches in various industries, especially in the "one-to-many" mode of the wind power industry, solving the problem of pairing hydraulic torque wrenches in this mode.

[0033] In some implementations of this embodiment, the establishment rule of the above calibration equation includes: taking the hydraulic pressure value output by the hydraulic source to the target hydraulic torque wrench as the independent variable, taking the torque output value of the target hydraulic torque wrench as the dependent variable, and using the least squares method to establish the calibration equation; wherein the formula of the calibration equation is: ;in, , , y represents the torque output value of the target hydraulic torque wrench, a represents the slope of the calibration equation, x represents the hydraulic pressure value output from the hydraulic source to the target hydraulic torque wrench, b represents the intercept of the calibration equation, and x i represents the hydraulic pressure value of the i-th preset calibration point, Represents the arithmetic mean of the hydraulic pressure values ​​of all preset calibration points, y i represents the torque output value of the target hydraulic torque wrench at the i-th preset calibration point, It represents the arithmetic mean of the torque output values ​​of the target hydraulic torque wrench of all preset calibration points, and n represents the number of preset calibration points.

[0034] Specifically, the method uses the hydraulic pressure value output from the hydraulic source to the target hydraulic torque wrench as the independent variable and the torque output value of the target hydraulic torque wrench as the dependent variable, and uses the least square method to establish a calibration equation, so that the torque output value of the target hydraulic torque wrench under any hydraulic pressure value can be calculated according to the calibration equation. The calibration equation (or calibration curve) given by this method can be used to derive and calculate the pressure conditions corresponding to any required torque, which provides great convenience for production applications.

[0035] In some implementations of this embodiment, the method further includes evaluating the uncertainty of the torque output value of the target hydraulic torque wrench represented by the calibrator indication; the uncertainty evaluation rule includes: integrating the uncertainty component introduced by the calibrator indication error u b and the uncertainty component introduced by the repeatability of torque measurement u R , the uncertainty value corresponding to the torque output value of the target hydraulic torque wrench is obtained; among them, the uncertainty component introduced by the indication error of the calibrator is u b The calculation formula is: ; Uncertainty component introduced by torque measurement repeatability u R The calculation rules include: according to the measured values ​​of the torque output value of the preset calibration point in each calibration process, using the Bessel formula Calculate the experimental standard deviation; based on n The uncertainty component introduced by the repeatability of torque measurement is calculated by taking the average value of the torque output value of the calibration process and the test standard deviation. u R ; Among them, the uncertainty component u R The calculation formula is ; The calculation formula for the uncertainty value corresponding to the torque output value of the target hydraulic torque wrench is: ; Among them, δ represents the maximum allowable error of the calibrator indication, represents the calibrator indication corresponding to the i-th calibration process, s represents the test standard deviation, It represents the arithmetic mean of the calibrator indications corresponding to n calibration processes. A numerical value representing the uncertainty of the torque output value of the target hydraulic torque wrench.

[0036] Specifically, since the torque value of the hydraulic torque wrench is a value-assigned calibration, that is, the torque wrench indication under a certain hydraulic pressure is the indication of the standard torque meter under the same pressure (same pressure source). The measurement model is: i = T i ; Where: Yi Indicates the torque value of the hydraulic torque wrench being calibrated, in N·m; T i It represents the measurement value of the standard torque meter in N·m. The uncertainty sources are mainly: (1) The uncertainty u introduced by the indication error of the standard torque meter b ; (2) The uncertainty component u introduced by the torque measurement repeatability due to various random factors R (including fluctuations in the hydraulic source, the impact of changes in environmental conditions during the measurement process, etc.) Among them, the standard uncertainty component u introduced by the indication error of the standard torque meter b The evaluation rules include: if the maximum allowable error of the standard torque meter indication is known to be δ, then the standard uncertainty introduced by the maximum allowable error of the standard torque meter is: In addition, the standard uncertainty component u introduced by the torque measurement repeatability due to various random factors is R The evaluation rules include: based on the actual measured data, the test standard deviation is calculated using the Bessel formula; the average value of n measurements is actually used as the calibration result, and the standard uncertainty introduced by the measurement repeatability is: . Then the combined standard uncertainty is .

[0037] In some implementations of this embodiment, the expanded uncertainty U = k·u C , k = 2, U is the expanded uncertainty.

[0038] Figure 3 FIG. 1 is a block diagram of a system for calibrating a hydraulic torque wrench provided by an embodiment of the present invention. Figure 3 As shown, an embodiment of the present invention provides a system for calibrating a hydraulic torque wrench, comprising: A calibration program execution module is used to sequentially execute calibration programs corresponding to a plurality of preset calibration points to obtain calibration data of each preset calibration point when it is determined that the target hydraulic torque wrench has completed resetting; wherein the calibration program corresponding to each preset calibration point includes an execution program of a calibration process corresponding to a preset calibration number of each preset calibration point, and the calibration data of each preset calibration point includes a hydraulic pressure value output to the target hydraulic torque wrench by a hydraulic source corresponding to each preset calibration point in each calibration process and a torque output value of the target hydraulic torque wrench; An index evaluation module, used to calculate the index value of each preset evaluation index corresponding to the target hydraulic torque wrench based on the calibration data of each preset calibration point; An accuracy level determination module, used to determine the accuracy level of the target hydraulic torque wrench based on the index values ​​of each preset evaluation index corresponding to the target hydraulic torque wrench; A calibration equation establishment module is used to establish a calibration equation between the torque output value of the target hydraulic torque wrench and the hydraulic pressure value output by the hydraulic source to the target hydraulic torque wrench according to the calibration data of each preset calibration point when the accuracy level of the target hydraulic torque wrench reaches the preset qualified level; wherein the calibration equation is used to calculate the torque output value of the target hydraulic torque wrench under any hydraulic pressure value.

[0039] Specifically, when determining that the target hydraulic torque wrench has completed the reset, the system sequentially executes the calibration procedures corresponding to the multiple preset calibration points, and obtains calibration data including the hydraulic pressure value output from the hydraulic source to the target hydraulic torque wrench and the torque output value of the target hydraulic torque wrench corresponding to each preset calibration point in each calibration process. Thus, according to the calibration data of each preset calibration point, the index value of each preset evaluation index corresponding to the target hydraulic torque wrench is calculated, and the index value of each preset evaluation index corresponding to the target hydraulic torque wrench is compared with the accuracy level of the hydraulic wrench, so as to determine the accuracy level of the target hydraulic torque wrench. When the accuracy level of the target hydraulic torque wrench reaches the preset qualified level, according to the calibration data of each preset calibration point, the hydraulic pressure value output from the hydraulic source to the target hydraulic torque wrench is used as the independent variable, and the torque output value of the target hydraulic torque wrench is used as the dependent variable, and a calibration equation is established, so that the torque output value of the target hydraulic torque wrench under any hydraulic pressure value can be calculated according to the calibration equation. The system adopts the technical route of "calibration without pump", which can realize the separate calibration of the hydraulic torque wrench head and hydraulic pump, and can reliably evaluate the accuracy of the wrench head, thus providing a reliable basis for the wrench head pairing in the "one-to-many" mode. It not only achieves the purpose of calculating the torque output value of the target hydraulic torque wrench under any hydraulic pressure value, but also realizes the automatic calibration of the hydraulic torque wrench. The system can be widely used in the calibration of hydraulic torque wrenches in various industries, especially in the "one-to-many" mode of the wind power industry, solving the problem of hydraulic torque wrench pairing in this mode.

[0040] The embodiment of the present invention further provides a machine-readable storage medium, on which instructions are stored. When the instructions are executed by the processor 100, the processor 100 is configured to execute the above-mentioned method for calibrating a hydraulic torque wrench.

[0041] Machine-readable storage media include permanent and non-permanent, removable and non-removable media, and can be implemented by any method or technology to store information. Information can be computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include temporary computer-readable media (transitory media), such as modulated data signals and carrier waves.

[0042] The embodiment of the present invention further provides an electronic device 10, which includes a memory 101, a processor 100, and a computer program 102 stored in the memory 101 and executable on the processor 100. When the processor 100 executes the computer program 102, the above-mentioned method for calibrating a hydraulic torque wrench is implemented.

[0043] like Figure 4 FIG. 1 is a schematic diagram of an electronic device provided by an embodiment of the present invention. Figure 4 As shown, the electronic device 10 of this embodiment includes: a processor 100, a memory 101, and a computer program 102 stored in the memory 101 and executable on the processor 100. When the processor 100 executes the computer program 102, the steps in the above method embodiment are implemented. Alternatively, when the processor 100 executes the computer program 102, the functions of each module / unit in the above device embodiment are implemented.

[0044] Exemplarily, the computer program 102 may be divided into one or more modules / units, one or more modules / units are stored in the memory 101, and are executed by the processor 100 to complete the present invention. One or more modules / units may be a series of computer program instruction segments capable of completing specific functions, and the instruction segments are used to describe the execution process of the computer program 102 in the electronic device 10. For example, the computer program 102 may be divided into a calibration program execution module, an indicator evaluation module, an accuracy level determination module, and a calibration equation establishment module.

[0045] The electronic device 10 may be a computing device such as a desktop computer, a notebook, a PDA, or a cloud server. The electronic device 10 may include, but is not limited to, a processor 100 and a memory 101. Those skilled in the art will appreciate that Figure 4 It is only an example of the electronic device 10 and does not constitute a limitation of the electronic device 10. It may include more or fewer components than shown in the figure, or a combination of certain components, or different components. For example, the electronic device may also include input and output devices, network access devices, buses, etc.

[0046] The processor 100 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or the processor may be any conventional processor, etc.

[0047] The memory 101 may be an internal storage unit of the electronic device 10, such as a hard disk or memory of the electronic device 10. The memory 101 may also be an external storage device of the electronic device 10, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card (FlashCard), etc. equipped on the electronic device 10. Further, the memory 101 may also include both an internal storage unit of the electronic device 10 and an external storage device. The memory 101 is used to store computer programs and other programs and data required by the electronic device 10. The memory 101 may also be used to temporarily store data that has been output or is to be output.

[0048] The technicians in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In practical applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated in a processing unit, or each unit can exist physically separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method embodiment, which will not be repeated here.

[0049] It should be understood by those skilled in the art that the embodiments of the present application may be provided as methods, systems, or computer program 102 products. Therefore, the present application may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may take the form of a computer program 102 product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0050] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program 102 products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by the computer program 102 instructions. These computer program 102 instructions can be provided to a processor 100 of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor 100 of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0051] These computer program 102 instructions may also be stored in a computer readable memory 101 that can direct a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer readable memory 101 produce an article of manufacture including an instruction device that implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0052] These computer program 102 instructions may also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for executing on the computer or other programmable device to implement the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0053] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0054] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included within the scope of the claims of the present application.

Claims

1. A method for calibrating a hydraulic torque wrench, characterized in that: include: When it is determined that the target hydraulic torque wrench has completed resetting, the calibration programs corresponding to the plurality of preset calibration points are sequentially executed to obtain calibration data of each preset calibration point; wherein the calibration program corresponding to each preset calibration point includes an execution program of the calibration process corresponding to the preset calibration times of each preset calibration point, and the calibration data of each preset calibration point includes the hydraulic pressure value output to the target hydraulic torque wrench by the hydraulic source corresponding to each preset calibration point in each calibration process and the torque output value of the target hydraulic torque wrench; Based on the calibration data of each preset calibration point, the index value of each preset evaluation index corresponding to the target hydraulic torque wrench is calculated; Determining the accuracy level of the target hydraulic torque wrench based on the indicator values ​​of each preset evaluation indicator corresponding to the target hydraulic torque wrench; When the accuracy level of the target hydraulic torque wrench reaches the preset qualified level, a calibration equation between the torque output value of the target hydraulic torque wrench and the hydraulic pressure value output by the hydraulic source to the target hydraulic torque wrench is established according to the calibration data of each preset calibration point; wherein the calibration equation is used to calculate the torque output value of the target hydraulic torque wrench at any hydraulic pressure value.

2. The method for calibrating a hydraulic torque wrench according to claim 1, characterized in that: The steps of the calibration process of any of the preset calibration points include: After the control calibrator performs zero point calibration and controls the hydraulic source to start, it is determined whether the target hydraulic torque wrench is in a normal operating state; When it is determined that the target hydraulic torque wrench is in a normal operating state, the hydraulic source is controlled to output a hydraulic pressure matching a preset calibration point to the target hydraulic torque wrench, and the hydraulic source pressure indication and the calibrator indication are recorded, and the hydraulic source pressure indication and the calibrator indication are used as calibration data of the preset calibration point in this calibration process; wherein the calibrator indication represents the torque output value of the target hydraulic torque wrench, and the hydraulic source pressure indication represents the hydraulic pressure value output by the hydraulic source to the target hydraulic torque wrench.

3. The method for calibrating a hydraulic torque wrench according to claim 1, characterized in that: The establishment rules of the calibration equation include: The hydraulic pressure value output from the hydraulic source to the target hydraulic torque wrench is used as the independent variable, and the torque output value of the target hydraulic torque wrench is used as the dependent variable. The least square method is used to establish the calibration equation; where, The calibration equation is: ;in, , , y represents the torque output value of the target hydraulic torque wrench, a represents the slope of the calibration equation, x represents the hydraulic pressure value output from the hydraulic source to the target hydraulic torque wrench, b represents the intercept of the calibration equation, and x i represents the hydraulic pressure value of the i-th preset calibration point, Represents the arithmetic mean of the hydraulic pressure values ​​of all preset calibration points, y i represents the torque output value of the target hydraulic torque wrench at the i-th preset calibration point, It represents the arithmetic mean of the torque output values ​​of the target hydraulic torque wrench of all preset calibration points, and n represents the number of preset calibration points.

4. The method for calibrating a hydraulic torque wrench according to claim 2, characterized in that: The preset evaluation index includes indication repeatability; The step of calculating the index values ​​of the preset evaluation indexes corresponding to the target hydraulic torque wrench based on the calibration data of the preset calibration points includes: According to the indication repeatability calculation formula, calculate the indication repeatability index value corresponding to the target hydraulic torque wrench; The calculation formula for the repeatability of the indication includes: , The index value representing the repeatability of the indication of the target hydraulic torque wrench corresponding to the i-th preset calibration point, Indicates the maximum value of the calibration instrument indication corresponding to the i-th preset calibration point, Indicates the minimum value of the calibration instrument indication corresponding to the i-th preset calibration point, Represents the arithmetic mean of the calibrator indications corresponding to the i-th preset calibration point.

5. The method for calibrating a hydraulic torque wrench according to claim 2, characterized in that: The preset evaluation index includes linear error; The step of calculating the index values ​​of the preset evaluation indexes corresponding to the target hydraulic torque wrench based on the calibration data of the preset calibration points includes: According to the linear error calculation formula, calculate the index value of the linear error corresponding to the target hydraulic torque wrench; The linear error calculation formula includes: , , Δξ j represents the residual of the j-th preset calibration point, wherein the residual of the j-th preset calibration point represents the difference between the measured value and the fitted value of the torque output value of the j-th preset calibration point, T j Represents the arithmetic mean of the torque output values ​​measured at the jth preset calibration point, T ej represents the fitting value of the torque output value of the jth preset calibration point, ξ represents the index value of the linear error of the target hydraulic torque wrench, T eF.S represents the fitting value of the torque output value of the target hydraulic torque wrench corresponding to the rated pressure of the target hydraulic torque wrench, Δξ max Indicates the maximum value among the residuals of each preset calibration point.

6. The method for calibrating a hydraulic torque wrench according to claim 2, characterized in that: The preset evaluation index includes interpolation error; The step of calculating the index values ​​of the preset evaluation indexes corresponding to the target hydraulic torque wrench based on the calibration data of the preset calibration points includes: According to the interpolation error calculation formula, calculate the index value of the interpolation error corresponding to the target hydraulic torque wrench; The interpolation error calculation formula includes: , I j The index value of the interpolation error of the jth preset calibration point, T j Represents the arithmetic mean of the torque output values ​​measured at the jth preset calibration point, T ej Represents the fitted value of the torque output value at the j-th preset calibration point.

7. The method for calibrating a hydraulic torque wrench according to claim 2, characterized in that: The method further includes evaluating the uncertainty of the torque output value of the target hydraulic torque wrench represented by the indication of the calibrator; The uncertainty assessment rules include: Comprehensive uncertainty components introduced by the calibrator indication error u b and the uncertainty component introduced by the repeatability of torque measurement u R , get the uncertainty value corresponding to the torque output value of the target hydraulic torque wrench; where, Uncertainty component introduced by the indication error of the calibrator u b The calculation formula is: ； Uncertainty components introduced by torque measurement repeatability u R The calculation rules include: Based on the measured values ​​of the torque output values ​​at the preset calibration points during each calibration process, the Bessel formula is used Calculate the experimental standard deviation; based on n The uncertainty component introduced by the repeatability of torque measurement is calculated by taking the average value of the torque output value of the calibration process and the test standard deviation. u R ; Among them, the uncertainty component u R The calculation formula is ; The calculation formula for the uncertainty value corresponding to the torque output value of the target hydraulic torque wrench is: ； in, δ Indicates the maximum allowable error of the calibrator indication. represents the calibrator indication corresponding to the i-th calibration process, s represents the test standard deviation, It represents the arithmetic mean of the calibrator indications corresponding to n calibration processes. A numerical value representing the uncertainty of the torque output value of the target hydraulic torque wrench.

8. A system for calibrating a hydraulic torque wrench, characterized in that: include: A calibration program execution module is used to sequentially execute calibration programs corresponding to a plurality of preset calibration points to obtain calibration data of each preset calibration point when it is determined that the target hydraulic torque wrench has completed resetting; wherein the calibration program corresponding to each preset calibration point includes an execution program of a calibration process corresponding to a preset calibration number of each preset calibration point, and the calibration data of each preset calibration point includes a hydraulic pressure value output to the target hydraulic torque wrench by a hydraulic source corresponding to each preset calibration point in each calibration process and a torque output value of the target hydraulic torque wrench; An index evaluation module, used to calculate the index value of each preset evaluation index corresponding to the target hydraulic torque wrench based on the calibration data of each preset calibration point; An accuracy level determination module, used to determine the accuracy level of the target hydraulic torque wrench based on the index values ​​of each preset evaluation index corresponding to the target hydraulic torque wrench; A calibration equation establishment module is used to establish a calibration equation between the torque output value of the target hydraulic torque wrench and the hydraulic pressure value output by the hydraulic source to the target hydraulic torque wrench according to the calibration data of each preset calibration point when the accuracy level of the target hydraulic torque wrench reaches a preset qualified level; wherein the calibration equation is used to calculate the torque output value of the target hydraulic torque wrench at any hydraulic pressure value.

9. A machine-readable storage medium having instructions stored thereon, characterized in that: When the instruction is executed by a processor, the processor is configured to perform the method for calibrating a hydraulic torque wrench as claimed in any one of claims 1 to 7.

10. An electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the method for calibrating a hydraulic torque wrench according to any one of claims 1 to 7 is implemented.

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