A method and device for measuring the drop time and impact force of a control rod drive line

Abstract

The present invention relates to the field of nuclear safety technology. A method and device for measuring the drop time and impact force of a control rod drive line are provided. The method and device comprise a drive line, a test container, a displacement sensor probe, a displacement sensor receiver, a stress measurement unit, a vibration measurement unit, and a processing unit. The method calibrates the drive line through a reference position and a reference position stress value σ0, and collects displacement data L, vibration data A, stress data σ, and the corresponding acquisition time T of each data during the drop process of the drive line in real time. Relationship diagrams of the displacement time series, vibration time series, and stress time series are generated, respectively. Coupled analysis is used to determine the starting and ending points of the drop, and the drop impact force and drop time are determined, thereby improving the accuracy and reliability of the experimental results.

Description

Technical Field

[0001] The present invention relates to the field of nuclear safety technology, and in particular to a method and device for measuring the rod drop time and impact force of a control rod drive line. Background Art

[0002] The control rod drive wire is a crucial actuator in the reactor control and nuclear safety protection system. Its primary function is to drive the control rod assembly up and down within the reactor core to regulate reactivity. Upon triggering a scram signal, the control rod assembly must rapidly descend under the influence of gravity and acceleration springs, achieving a safe shutdown. Therefore, the rationality of the drive wire design directly impacts the inherent safety and operational stability of the nuclear reactor.

[0003] In the event of an accident or emergency, if the control rod drive wire's rod drop process is not smooth or the rod drop time exceeds the specified time, rapid shutdown may not be achieved, and even core reactivity may become uncontrolled, posing a serious safety risk. To ensure that the control rod drive wire can drop normally during actual operation, after completing the preliminary design, the drive wire needs to be tested under open conditions. The rod drop time and impact force in air and water are measured to verify the rationality of the design and thus consolidate the structural design of the control rod drive wire. Summary of the Invention

[0004] The object of the present invention is to provide a method and device for measuring the rod drop time and impact force of a control rod drive line, so as to solve the above technical problems and improve the accuracy and reliability of the experimental results.

[0005] The embodiment of the present invention is achieved through the following technical solution: a method and device for measuring the rod drop time and impact force of a control rod drive line, comprising the following steps:

[0006] S1. Drop the driving wire into the bottom of the test container and keep it still, calibrate the reference position and the reference position stress value σ0;

[0007] S2, lift the driving line to the designed height and calibrate the initial rod position L0;

[0008] S3, releasing the driving line, and collecting in real time the displacement data L of the free-falling rod of the driving line, the vibration data A of the test container, the stress data σ on the bottom of the test container, and the collection time T corresponding to each data;

[0009] S4. Generate a displacement time series, a vibration time series, and a stress time series based on the displacement data L, the vibration data A, the stress data σ, and the acquisition time T corresponding to each data;

[0010] S5. According to the displacement time series, the point where the displacement data L begins to change is taken as the starting point of the rod drop, and the starting time T0 corresponding to the starting point of the rod drop is recorded. The displacement time series, vibration time series and stress time series are coupled and processed to determine the end point of the rod drop. The difference between the stress value σ1 at the end point of the rod drop and the stress value σ0 at the reference position is recorded as the impact force of the rod drop, and the difference between the end point time T1 corresponding to the end point of the rod drop and the starting time T0 is the rod drop time.

[0011] Furthermore, the rod drop end point is the point where the vibration data A value is the maximum, the stress data σ value is the maximum, and the change value of the displacement data L and the initial rod position L0 meets the design height value.

[0012] A device for measuring the rod drop time and impact force of a control rod drive line comprises a drive line, a test container, and a processing unit. A displacement sensor probe is provided at the top of the drive line, a displacement sensor receiver is provided above the displacement sensor probe, and cooperates with the displacement sensor probe to detect the displacement of the drive line. A stress measurement unit is provided at the bottom inner of the test container to detect the impact stress of the drive line, and a vibration measurement unit is provided at the bottom outer of the test container to detect the vibration of the test container. The displacement sensor receiver, the stress measurement unit, and the vibration measurement unit are electrically connected to the processing unit respectively.

[0013] Furthermore, the relative height position of the displacement sensor receiver is adjustable.

[0014] Furthermore, the stress measuring unit adopts a strain gauge.

[0015] Furthermore, the vibration measuring unit adopts a vibration accelerometer and is connected to the processing unit through an amplifier.

[0016] The present invention has at least the following advantages and beneficial effects: through calibration of the reference position and the reference position stress value σ0, and real-time collection of displacement data L, vibration data A, stress data σ during the falling process of the driving line, and the collection time T corresponding to each data, the displacement time series, vibration time series and stress time series relationship diagrams are generated respectively, and the coupling analysis is used to determine the starting point and end point of the rod drop, and the impact force and time of the rod drop are determined, thereby improving the accuracy and reliability of the experimental results. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1A flow chart of a method for measuring the rod drop time and impact force of a control rod drive line provided by the present invention;

[0019] Figure 2 A schematic structural diagram of a device for measuring the rod drop time and impact force of a control rod drive line provided by the present invention;

[0020] Icon: 1- driving line, 2- test container, 31- displacement sensor probe, 32- displacement sensor receiver, 4- stress measurement unit, 5- vibration measurement unit, 6- processing unit. DETAILED DESCRIPTION

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0022] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort shall fall within the scope of protection of the present invention.

[0023] Example

[0024] like Figure 1 As shown, in this embodiment, a method and device for measuring the rod drop time and impact force of a control rod drive line is mainly disclosed, including the following steps:

[0025] S1. Drop the driving wire 1 into the bottom of the test container 2 and keep it still. Calibrate the reference position and the reference position stress value σ0. At this time, the reference position corresponds to the standard drop end point of the driving wire 1, and the reference position stress value σ0 is the stress generated by the weight of the driving wire 1 itself.

[0026] S2. Lift the driving line 1 to the designed height and calibrate the initial rod position L0. Specifically, the initial rod position L0 is the sum of the reference position and the designed height;

[0027] S3. Release driving wire 1 and collect in real time the displacement data L of the free-falling rod of driving wire 1, the vibration data A of test container 2, the stress data σ on the bottom of test container 2, and the corresponding collection time T of each data. Specifically, during the falling process of driving wire 1, the displacement data L of driving wire 1 are collected at microsecond time intervals. When driving wire 1 falls to the bottom of test container 2, the stress data σ on the bottom of test container 2 and the vibration data A of driving wire 1 on test container 2 are monitored throughout the entire impact process of driving wire 1.

[0028] S4. Generate a displacement time series, a vibration time series, and a stress time series based on the displacement data L, the vibration data A, the stress data σ, and the acquisition time T corresponding to each data. The displacement time series reflects the relationship between the displacement and time during the entire falling process of the driving wire 1 (with time as the horizontal axis and displacement as the vertical axis). The vibration time series reflects the relationship between the vibration generated by the driving wire 1 on the test container 2 and time during the entire falling process (with time as the horizontal axis and vibration as the vertical axis). The stress time series reflects the relationship between the stress generated by the driving wire 1 on the bottom of the test container 2 and time during the entire falling process (with time as the horizontal axis and stress as the vertical axis).

[0029] S5. Based on the displacement time series, the point where the displacement data L begins to change is taken as the rod drop starting point, and the starting time T0 corresponding to the rod drop starting point is recorded. The displacement time series, vibration time series, and stress time series are coupled to process to determine the rod drop end point. The difference between the stress value σ1 at the rod drop end point and the stress value σ0 at the reference position is recorded as the rod drop impact force. The difference between the end time T1 corresponding to the rod drop end point and the starting time T0 is the rod drop time.

[0030] Through calibration of the reference position and the reference stress value σ0, and real-time collection of the displacement data L, vibration data A, stress data σ during the falling process of the driving wire 1 and the corresponding acquisition time T, the relationship diagrams of the displacement time series, vibration time series and stress time series are generated respectively. The coupling analysis is used to determine the starting point and end point of the rod drop, and the impact force and time of the rod drop are determined, thereby improving the accuracy and reliability of the experimental results.

[0031] Furthermore, in specific implementation, the above-mentioned rod drop end point provided in the embodiment of the present invention is the point where the vibration data A value is the largest, the stress data σ value is the largest, and the change value of the displacement data L and the initial rod position L0 meets the design height value, that is, the end point time corresponding to the judged rod drop end point should simultaneously meet the requirements of being able to correspond to the maximum vibration data A value in the vibration time series, the maximum stress data σ value in the stress time series, and the difference between the rod drop end point position and the initial rod position L0 being the design height value; if any one of the items is not met, it means that the set of measurement data is invalid and needs to be remeasured.

[0032] like Figure 2As shown, in this embodiment, a device for measuring the drop time and impact force of a control rod drive line is also disclosed, including a drive line 1, a test container 2, and a processing unit 6. A displacement sensor probe 31 is provided at the top of the drive line 1, and a displacement sensor receiver 32 is provided above the displacement sensor probe 31 for cooperating with the displacement sensor probe 31 to detect the displacement of the drive line 1. A stress measurement unit 4 is provided at the bottom of the test container 2 for detecting the impact stress of the drive line 1, and a vibration measurement unit 5 is provided at the bottom of the test container 2 for detecting the vibration of the test container 2. The displacement sensor receiver 32, the stress measurement unit 4, and the vibration measurement unit 5 are electrically connected to the processing unit 6 respectively. Specifically, the test container 2 can adopt existing technology and is a cylindrical structure for accommodating the drive line 1. A buffer structure is provided at the bottom of the test container 2. The processing unit 6 has a high acquisition frequency and can collect and record the acquisition time of each data.

[0033] Furthermore, in a specific implementation, the relative height position of the above-mentioned displacement sensor receiver 32 provided in the embodiment of the present invention is adjustable. Specifically, the displacement sensor probe 31 is fixed on the top surface of the driving wire 1 and moves with the driving wire 1. The displacement sensor receiver 32 is arranged at a certain distance directly above the displacement sensor probe 31 through tooling, and is relatively fixed and does not contact the driving wire 1, thereby adapting to different experimental requirements and improving the flexibility and applicability of the equipment.

[0034] Furthermore, in specific implementation, the stress measurement unit 4 provided in the embodiment of the present invention uses a strain gauge, which has the characteristics of high sensitivity and strong adaptability, and can capture tiny stress changes, thereby enhancing the accuracy of stress measurement.

[0035] Furthermore, in specific implementation, the vibration measurement unit 5 provided in the embodiment of the present invention adopts a vibration accelerometer and is connected to the processing unit 6 through an amplifier, which effectively improves the detection capability of tiny vibration signals and ensures that stable data can still be obtained under high-frequency vibration conditions.

[0036] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A method for measuring the drop time and impact force of a control rod drive line, characterized in that: The following steps are involved: S1. Drop the driving wire (1) into the bottom of the test container (2) and keep it still, and calibrate the reference position and reference position stress value. ; S2, lifting the driving line (1) to the designed height and calibrating the initial rod position L0; S3, releasing the driving wire (1), and collecting in real time the displacement data L of the free-falling rod of the driving wire (1), the vibration data A of the test container (2), and the stress data on the bottom of the test container (2) And the collection time T corresponding to each data; S4, according to the displacement data L, the vibration data A, the stress data The acquisition time T corresponding to each data is used to generate a displacement time series, a vibration time series and a stress time series respectively; S5. Based on the displacement time series, the point where the displacement data L begins to change is used as the rod drop starting point, and the starting time T0 corresponding to the rod drop starting point is recorded. The displacement time series, the vibration time series, and the stress time series are coupled and processed to determine the rod drop end point, and the stress value at the rod drop end point is recorded. With the reference stress value The difference between the end time T1 and the starting time T0 corresponding to the end point of the rod drop is the rod drop time; the end point of the rod drop is when the vibration data A value is the maximum and the stress data The point where the value is the largest and the change between the displacement data L and the initial rod position L0 meets the design height value.

2. A device for measuring the control rod drive line drop time and impact force based on the method of claim 1, comprising the drive line (1), the test container (2) and a processing unit (6), characterized in that: A displacement sensor probe (31) is provided at the top of the driving line (1); a displacement sensor receiver (32) is provided above the displacement sensor probe (31) and cooperates with the displacement sensor probe (31) to detect the displacement of the driving line (1); a stress measuring unit (4) is provided at the bottom of the inner part of the test container (2) to detect the impact stress of the driving line (1); a vibration measuring unit (5) is provided at the bottom of the outer part of the test container (2) to detect the vibration of the test container (2); the displacement sensor receiver (32), the stress measuring unit (4) and the vibration measuring unit (5) are respectively electrically connected to the processing unit (6).

3. A device according to claim 2, characterized in that The relative height position of the displacement sensor receiver (32) is adjustable.

4. A device according to claim 2, characterized in that The stress measuring unit (4) adopts a strain gauge.

5. A device according to claim 2, characterized in that The vibration measuring unit (5) adopts a vibration accelerometer and is connected to the processing unit (6) through an amplifier.

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