Detection method for non-destructively evaluating state of chemical fiber cable

Abstract

The invention discloses a detection method for non-destructively evaluating the state of a chemical fiber cable. The detection method comprises the following steps: S1, equipment installation: installing at least one piece of equipment for detection in the whole length of the chemical fiber cable; s2, mounting and fixing the chemical fiber cable: respectively mounting and fixing two ends of the chemical fiber cable; s3, detecting the state of the chemical fiber cable: detecting the vibration generated by the cable through a vibration measurement sensor; providing, by a distance sensor, rope elongation data indicative of a change in distance between two or more known features of the rope product; and S4, data processing and comparison, wherein the background monitors and converts the data detected when the chemical fiber cable is used in real time to obtain the load and elongation curve of the chemical fiber cable. The problems that an existing cable cannot be subjected to nondestructive testing when used, and the residual strength of the chemical fiber cable cannot be obtained are solved.

Description

Technical Field

[0001] The invention relates to the field of cable detection, and in particular to a detection method for non-destructively evaluating the state of a chemical fiber cable. Background Art

[0002] Synthetic ropes and other rope products are used in a variety of applications in many industries. For example, the marine industry may use rope products for mooring operations to anchor ships at piers, while the construction industry may use rope products for cranes to handle and transport heavy objects. In each of these various applications, a load is applied to the rope product, resulting in a force being exerted on the rope product.

[0003] When the cable is in use, the two ends of the cable are fixed to the mobile end and the fixed end respectively, and the cable will be in a taut state. When the cable is in a taut state, the cable will generate amplitude, and the cable will be constantly subjected to tension. When the tension on the cable is at its limit, the cable will break. In addition, the cable will experience strength attenuation during use due to wear, cutting, fatigue, impact load, creep, ultraviolet rays and other factors. The existing technology mainly monitors the real-time force on the cable, and the residual strength of the chemical fiber cable cannot be obtained.

[0004] In response to this problem, the present invention proposes to evaluate the current physical state of the chemical fiber cable during use by non-destructive evaluation of the axial stiffness value of the chemical fiber cable. This is because during the use of the chemical fiber cable, the strength of the cable itself will gradually decay, so the stiffness value within a certain elongation range will change. Therefore, the health state of the rope product can be estimated based on the determined axial stiffness value and the obtained reference value, and the health state indicates the current physical state of the chemical fiber cable. Summary of the invention

[0005] The purpose of the present invention is to provide a detection method for non-destructively evaluating the state of a chemical fiber cable, which solves the problem that the cable cannot be monitored and evaluated during operation and the risk of the cable cannot be eliminated in time.

[0006] The above technical objectives of the present invention are achieved through the following technical solutions:

[0007] A detection method for non-destructively evaluating the state of a chemical fiber cable, characterized in that it comprises the following steps: S1 equipment installation: installing at least one device for detection within the entire length of the chemical fiber cable, the detection device being placed inside the chemical fiber cable when the chemical fiber cable is braided, the detection device comprising: a vibration sensor, a distance sensor, a controller and a wireless transmission module;

[0008] S2 chemical fiber cable installation and fixation: install and fix the two ends of the chemical fiber cable respectively;

[0009] S3 Chemical fiber cable state detection: When the chemical fiber cable is in use, the cable will be in a taut stress state, and the cable in the taut state will vibrate. The vibration generated by the cable is detected by the vibration sensor; secondly, the cable will also deform when subjected to tension, and the distance sensor provides the cable elongation data indicating the change in the distance between two or more known features of the rope product; the vibration frequency of the cable and the elongation data of the cable are determined based on the vibration sensor and the distance sensor;

[0010] S4 Data processing and comparison: The background monitors and converts the data detected when the chemical fiber cable is in use in real time to obtain the load and elongation curve of the chemical fiber cable, thereby determining the axial stiffness value (EA) of the chemical fiber cable, and estimating the health status of the chemical fiber cable based on the determined axial stiffness value, thereby achieving non-destructive evaluation of the cable status.

[0011] Preferably, in step S1, the detection equipment will be connected to an external power cord, one end of the power cord will pass through the chemical fiber cable, and when the status of the chemical fiber cable is monitored, the power cord will be connected to an external power supply device to power the detection equipment.

[0012] Preferably, in step S1, the controller includes a memory and one or more processors, and the data monitored by the sensor can be processed by the processor. The data will be stored in the memory, and the processor will also transmit the data wirelessly through the wireless transmission module.

[0013] Preferably, in step S3, the data detected by the vibration sensor is detected by a cable tension tester, and the cable tension tester detects the tension by a vibration frequency method. The vibration frequency method is based on the string vibration theory. When a string with a length of l and a unit weight of m is fixed at both ends, the tension force is T, and the vibration fundamental frequency of the string can be expressed as: That is, the tension T can be expressed as T = 4ml 2 f 2 .

[0014] Preferably, in the above test method, the high-order (nth-order) natural frequency 1.

[0015] Preferably, when the tension value of the cable is detected and the change in the distance between two or more known features of the cable product detected by two distance sensors, i.e., the elongation, the stiffness value of the cable can be obtained by dividing the change in the tension value (ΔT) by the elongation (Δε). The residual strength of the cable is evaluated by the change in the stiffness value of the cable, thereby evaluating the health status of the cable.

[0016] Preferably, wherein the sensor data is obtained from sensors on the rope product, and wherein determining the axial stiffness is limited to sensor data at discrete points or discrete sub-lengths along the entire length.

[0017] Preferably, the sensor data is obtained by detecting a sensor of a portion of the synthetic fiber cable, wherein the sensor data from the portion is obtained multiple times within a predetermined time period, and further comprises determining whether the health state exceeds a threshold value of a health decline rate.

[0018] Beneficial effect: The present application provides a detection method for non-destructively evaluating the state of chemical fiber cables, so that the health state of the cables can be evaluated without damaging the cables. Vibration sensors and distance sensors installed inside the cables can monitor the vibration and deformation of the cables during use in real time, thereby obtaining real-time status data of the cables. The data collected by the vibration sensors and distance sensors, combined with background data processing, can be used to accurately calculate the axial stiffness value of the cables, and then evaluate the health state of the cables. Through real-time monitoring and evaluation of the cable state, potential problems with the cables can be discovered in time, so that preventive maintenance measures can be taken to avoid breakage or other damage to the cables during use. This method can detect abnormal conditions of the cables in time, thereby reducing safety accidents caused by cable breakage or damage, and improving the overall safety of operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the process of an embodiment;

[0020] Figure 2 The embodiment is a schematic diagram for showing a lossless device on a cable on a cable;

[0021] Figure 3 The embodiment is used to show the curve diagram of the initial extension rate and tension value of the cable;

[0022] Figure 4 The embodiment is used to show the curve diagram of the extension rate and the tension value of the cable after it is put into use;

[0023] Figure 5 The embodiment is used to show the curve diagram of the extension rate and tension value of the cable after long-term use. DETAILED DESCRIPTION

[0024] The following is only a preferred embodiment of the present invention, and the protection scope is not limited to this embodiment. All technical solutions under the concept of the present invention should belong to the protection scope of the present invention. At the same time, it should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

[0025] See Figures 1 to 5 As shown, a detection method for non-destructively evaluating the state of a chemical fiber cable is characterized in that it includes the following steps: S1 equipment installation: at least one device for detection is installed within the entire length of the chemical fiber cable, and the detection device is placed inside the chemical fiber cable when the chemical fiber cable is braided, and the detection device includes: a vibration sensor, a distance sensor, a controller and a wireless transmission module, the vibration sensor: used to detect the vibration generated by the cable under stress, and the distance sensor: used to measure the deformation of the cable under stress, that is, the elongation data of the cable;

[0026] wherein the sensor data is obtained by various sensors on the rope product, and wherein determining the axial stiffness is limited to sensor data at discrete points or discrete sub-lengths along the entire length, wherein the sensor data is obtained by sensor detection of a portion of the synthetic fiber rope, wherein the sensor data from the portion is obtained multiple times within a predetermined time period, and further comprising determining whether the health state exceeds a threshold value of the health decline rate;

[0027] The detection equipment will be connected to an external power cord, one end of which will pass through the chemical fiber cable. When the status of the chemical fiber cable is monitored, the power cord will be connected to an external power supply device to realize power supply to the detection equipment;

[0028] The controller includes a memory and one or more processors. The processor can process the data monitored by the sensor. The data will be stored in the memory, and the processor will also transmit the data wirelessly through the wireless transmission module.

[0029] S2 chemical fiber cable installation and fixation: install and fix the two ends of the chemical fiber cable respectively.

[0030] S3 Chemical fiber cable state detection: When the chemical fiber cable is in use, the cable will be in a taut stress state, and the cable in the taut state will vibrate. The vibration generated by the cable is detected by the vibration sensor; secondly, the cable will also deform when subjected to tension, and the distance sensor provides the cable elongation data indicating the change in the distance between two or more known features of the rope product; the vibration frequency of the cable and the elongation data of the cable are determined based on the vibration sensor and the distance sensor;

[0031] In step S3, the data detected by the vibration sensor will be tested by the cable tension tester. The cable tension tester detects the tension by the vibration frequency method. The vibration frequency method is based on the string vibration theory. When a string with a length of l and a unit weight of m is fixed at both ends, the tension is T, and the fundamental frequency of the string vibration can be expressed as That is, the tension T can be expressed as T = 4ml 2 f 2 In the above test method, the high-order (nth-order) natural frequency

[0032] When the tension value of the cable is detected and the change in the distance between two or more known features of the cable product detected by two distance sensors, that is, the elongation, the stiffness value of the cable can be obtained by dividing the change in tension value (ΔT) by the elongation (Δε). The residual strength of the cable is evaluated by the change in the stiffness value of the cable, thereby evaluating the health status of the cable.

[0033] like Figure 3 As shown, the distance sensor installed inside the cable detects the change in the extension rate between the two end points of the cable. When the cable is first used, it will be subjected to a pulling force, causing the cable to gradually deform, that is, the distance sensor between the two end points will detect the change in the elongation rate of the cable, and the cable will deform in length. Since the tension value (ΔT) of the cable is related to the length of the cable, as the elongation rate (Δε) of the cable, that is, the length changes, the tension value of the cable will also increase. Therefore, at any stage, the stiffness value of the cable can be obtained by dividing the change in tension value (ΔT) by the elongation rate (Δε). To measure whether the cable is in a healthy state.

[0034] like Figure 4 As shown in the figure, as the cable is used, the strength of the cable will gradually decrease. When the distance sensor detects the elongation (Δε) of the cable, the force value of the cable itself will decrease. At this time, the stiffness value of the cable is obtained by dividing the change in tension value (ΔT) by the elongation (Δε). However, the reduction in cable strength does not significantly reduce the cable's elongation at break, so the remaining cable strength is calculated to be 75% MBS (minimum breaking force), which is less than the threshold, and the system does not alarm. The threshold is set to 60% MBS.

[0035] like Figure 5 As shown in the figure, as the cable continues to be used, the strength of the cable will continue to decay. When the distance sensor detects the elongation (Δε) of the cable, the force value of the cable itself will decrease. At this time, the stiffness value of the cable is obtained by dividing the change in tension value (ΔT) by the elongation (Δε). However, a decrease in cable strength does not significantly reduce the cable's elongation at break. Therefore, it is calculated that the remaining strength of the cable is 50% MBS. When the threshold is exceeded, the system alarms. At this time, the cable is at a dangerous value and needs to be replaced in time to prevent it from breaking.

[0036] S4 Data processing and comparison: The background system monitors and processes the data collected from the sensors in real time. By analyzing the vibration frequency and elongation data, the load and elongation curves of the cable can be obtained. Using these curves, the axial stiffness value of the cable can be determined. By comparing the actual measured axial stiffness value with the preset reference value, the health status of the cable can be non-destructively evaluated.

Claims

1. A method for non-destructively evaluating the state of a chemical fiber cable, characterized in that: The following steps are involved: S1 Equipment installation: at least one device for detection is installed throughout the entire length of the chemical fiber cable. The detection device is placed inside the chemical fiber cable when the chemical fiber cable is braided. The detection device includes: a vibration sensor, a distance sensor, a controller and a wireless transmission module; S2 chemical fiber cable installation and fixation: install and fix the two ends of the chemical fiber cable respectively; S3 Chemical fiber cable state detection: When the chemical fiber cable is in use, the cable will be in a taut stress state, and the cable in the taut state will vibrate. The vibration generated by the cable is detected by the vibration sensor; secondly, the cable will also deform when subjected to tension, and the distance sensor provides the cable elongation data indicating the change in the distance between two or more known features of the rope product; the vibration frequency of the cable and the elongation data of the cable are determined based on the vibration sensor and the distance sensor; S4 Data processing and comparison: The background monitors and converts the data detected when the chemical fiber cable is in use in real time to obtain the load and elongation curve of the chemical fiber cable, thereby determining the axial stiffness value (EA) of the chemical fiber cable, and estimating the health status of the chemical fiber cable based on the determined axial stiffness value, thereby achieving non-destructive evaluation of the cable status.

2. A method for non-destructive evaluation of the state of a chemical fiber cable according to claim 1, characterized in that: In step S1, all detection devices will be connected to an external power cord, one end of which will pass through a synthetic fiber cable. When the status of the synthetic fiber cable is monitored, the power cord will be connected to an external power supply device to power the detection device.

3. A method for non-destructive evaluation of the state of a chemical fiber cable according to claim 1, characterized in that: In step S1, the controller includes a memory and one or more processors. The data monitored by the sensor can be processed by the processor. The data will be stored in the memory, and the processor will also transmit the data wirelessly through the wireless transmission module.

4. A method for non-destructive evaluation of the state of a chemical fiber cable according to claim 1, characterized in that: In step S3, the data detected by the vibration sensor will be tested by the cable tension tester. The cable tension tester detects the tension by the vibration frequency method. The vibration frequency method is based on the string vibration theory. When a string with a length of l and a unit weight of m is fixed at both ends, the tension is T, and the fundamental frequency of the string vibration can be expressed as That is, the tension T can be expressed as T = 4ml 2 f 2 .

5. A method for non-destructive evaluation of the state of a chemical fiber cable according to claim 4, characterized in that: In the above test method, the high-order (nth-order) natural frequency 6. According to the detection method for non-destructive evaluation of the state of a chemical fiber cable according to claim 4, when the change in the tension value of the cable and the distance between two or more known features of the cable product detected by two distance sensors, i.e., the elongation, the stiffness value of the cable can be obtained by dividing the change in the tension value (ΔT) by the elongation (Δε). The residual strength of the cable is evaluated by the change in the stiffness value of the cable, thereby evaluating the health status of the cable.

7. A method for non-destructive evaluation of the state of a chemical fiber cable according to claim 1, characterized in that: Wherein sensor data is obtained from sensors on the rope product, and wherein determining the axial stiffness is limited to sensor data at discrete points or discrete sub-lengths along the entire length.

8. A method for non-destructive evaluation of the state of a chemical fiber cable according to claim 1, characterized in that: The sensor data is obtained by detecting a sensor of a portion of the synthetic fiber cable, wherein the sensor data from the portion is obtained multiple times within a predetermined time period, and further includes determining whether the health state exceeds a threshold value of a health decline rate.

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