CN112304236A - On-line monitoring device for high-strength bolt tightness - Google Patents

On-line monitoring device for high-strength bolt tightness Download PDF

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Publication number
CN112304236A
CN112304236A CN202011315596.6A CN202011315596A CN112304236A CN 112304236 A CN112304236 A CN 112304236A CN 202011315596 A CN202011315596 A CN 202011315596A CN 112304236 A CN112304236 A CN 112304236A
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Prior art keywords
bolt
strain sensor
signal
tightness
monitoring device
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CN202011315596.6A
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Chinese (zh)
Inventor
彭金宁
南江
裴海林
陈少华
汪俊波
牛瑞杰
刘诚威
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Xian Thermal Power Research Institute Co Ltd
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Xian Thermal Power Research Institute Co Ltd
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Priority to CN202011315596.6A priority Critical patent/CN112304236A/en
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01BMEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B11/00Measuring arrangements characterised by the use of optical techniques
    • G01B11/16Measuring arrangements characterised by the use of optical techniques for measuring the deformation in a solid, e.g. optical strain gauge
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01BMEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B7/00Measuring arrangements characterised by the use of electric or magnetic techniques
    • G01B7/16Measuring arrangements characterised by the use of electric or magnetic techniques for measuring the deformation in a solid, e.g. by resistance strain gauge
    • G01B7/18Measuring arrangements characterised by the use of electric or magnetic techniques for measuring the deformation in a solid, e.g. by resistance strain gauge using change in resistance
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01LMEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L5/00Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes
    • G01L5/24Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes for determining value of torque or twisting moment for tightening a nut or other member which is similarly stressed
    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B21/00Alarms responsive to a single specified undesired or abnormal condition and not otherwise provided for
    • G08B21/18Status alarms
    • G08B21/182Level alarms, e.g. alarms responsive to variables exceeding a threshold

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Business, Economics & Management (AREA)
  • Emergency Management (AREA)
  • Testing Of Devices, Machine Parts, Or Other Structures Thereof (AREA)

Abstract

本发明公开了一种高强螺栓紧固度的在线监测装置,属于在线监测领域。本发明包括螺栓,螺栓内固设有管型应变传感器,管型应变传感器的信号传输线延伸到螺栓外,信号传输线连接有信号采集处理模块,信号采集处理模块与单片机MCU相连;信号采集处理模块用于接收并处理管型应变传感器的信号,并发送给单片机MCU;单片机MCU用于将接收到信号与设定值进行比较,当接收的信号偏离设定值预设范围时,则发出报警信号。本发明结构简单、通用化程度高,可适应各种工业紧固场景的使用需求,以合理评估和安排运维工作。

Figure 202011315596

The invention discloses an on-line monitoring device for the tightness of high-strength bolts, belonging to the field of on-line monitoring. The invention comprises a bolt, a tubular strain sensor is fixed inside the bolt, the signal transmission line of the tubular strain sensor extends outside the bolt, the signal transmission line is connected with a signal acquisition and processing module, and the signal acquisition and processing module is connected with the single chip MCU; It is used to receive and process the signal of the tubular strain sensor, and send it to the single chip MCU; The invention has a simple structure and a high degree of generalization, and can adapt to the use requirements of various industrial fastening scenarios, so as to reasonably evaluate and arrange the operation and maintenance work.

Figure 202011315596

Description

On-line monitoring device for high-strength bolt tightness
Technical Field
The invention belongs to the field of online detection, and particularly relates to an online monitoring device for the tightness of a high-strength bolt.
Background
In industrial scenes such as operation of mechanical equipment and the like, high-strength bolts are often used for fixing, for example, bolts for the top cover of a hydroelectric generating set in a hydropower station are fixed. Once bolt loosening or fatigue fracture occurs, there is a possibility of a significant safety accident due to the roof being pushed open under high water pressure. If the bolt of the tower barrel of the wind generating set is loosened or subjected to fatigue fracture, serious accidents such as tower falling and the like can be caused. Therefore, the online monitoring of the high-strength bolt fastening condition is significant.
Disclosure of Invention
The invention aims to overcome the defect that the fastening condition of a high-strength bolt is not monitored, and provides an on-line monitoring device for the fastening degree of the high-strength bolt.
In order to achieve the purpose, the invention adopts the following technical scheme to realize the purpose:
an on-line monitoring device for the tightness of a high-strength bolt comprises a bolt, wherein a tubular strain sensor is fixedly arranged in the bolt, a signal transmission line of the tubular strain sensor extends out of the bolt, the signal transmission line positioned outside the bolt is connected with a signal acquisition and processing module, and the signal acquisition and processing module is connected with a single-chip Microcomputer (MCU);
the signal acquisition processing module is used for receiving signals of the tube-type strain sensor, converting the signals into digital signals and sending the digital signals to the MCU;
the MCU is used for comparing the received signal with a set value, and sending an alarm signal when the received signal deviates from the preset range of the set value.
Furthermore, a hexagonal flange is arranged at one end of the bolt, a mounting hole is formed in the bolt close to the hexagonal flange, and threads are arranged in the mounting hole;
the shell of the tubular strain sensor is provided with threads, the tubular strain sensor is arranged in the mounting hole in a threaded fit mode, and the signal transmission line extends out of the bolt through the hexagonal flange.
Furthermore, weather-resistant glue for sealing is arranged in the mounting hole.
Furthermore, the periphery of the screw rod of the bolt is provided with threads.
Further, the pipe-shaped strain sensor and the bolt are welded into a whole.
Furthermore, the tubular strain sensor is a fiber grating strain sensor, and the corresponding signal acquisition processing module has a photoelectric conversion function.
Furthermore, the tubular strain sensor is a resistance strain sensor, and the corresponding signal acquisition and processing module has an A/D conversion function.
Further, a fastener is arranged outside the bolt;
when the fastening force of the bolt reaches a preset torque, the output signal of the tubular strain sensor corresponds to the normal elongation of the bolt;
along with the alternating action of mechanical motion, vibration and temperature change, the tightness of the bolt is reduced, and the output signal of the tubular strain sensor is reduced along with the reduction;
and when the output signal of the tubular strain sensor deviates from the preset range of the signal of the normal elongation of the bolt, an alarm signal is sent out.
Compared with the prior art, the invention has the following beneficial effects:
according to the on-line monitoring device for the high-strength bolt tightness, the fastening state of the bolt is monitored in real time by arranging the tubular strain sensor, and an alarm signal is sent out when the fastening state is larger than a preset range, so that the fastening state of the bolt can be actively provided to avoid safety accidents. The invention has simple structure and high generalization degree, can meet the use requirements of various industrial fastening scenes and reasonably evaluate and arrange operation and maintenance work.
Drawings
FIG. 1 is a schematic structural view of the present invention;
FIG. 2 is a schematic view of the bolt of the present invention when mounted on a flange;
fig. 3 is a schematic diagram of an expanded structure of the present invention.
Wherein: 1-a bolt; 2-tube type strain sensors; 101-hexagonal flange; 102-a screw; 3-weather-resistant glue; 4-signal transmission line.
Detailed Description
In order to make the technical solutions of the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the invention described herein are capable of operation in sequences other than those illustrated or described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
The invention is described in further detail below with reference to the accompanying drawings:
referring to fig. 1, fig. 1 is a schematic structural diagram of the present invention, and an on-line monitoring device for high-strength bolt tightness includes a bolt 1, a tubular strain sensor 2, a signal acquisition processing module, and a single chip microcomputer. A hexagonal flange 101 is arranged at one end of the bolt 1, a mounting hole is formed in the bolt 1 close to the hexagonal flange 101, threads are arranged in the mounting hole, and threads are arranged on the periphery of the screw 102; the shell of the tubular strain sensor 2 is provided with threads; the tubular strain sensor 2 is installed in the bolt 1 through screwing, the tubular strain sensor 2 and the bolt 1 are reliably connected into a whole through welding, and weather-resistant glue 3 is sealed in the installation hole; a signal transmission line 4 of the tubular strain sensor 2 extends out of the bolt 1 through a hexagonal flange 101, the other end of the signal transmission line 4 is connected with a signal acquisition and processing module, and the signal acquisition and processing module processes a strain sensor signal and transmits the strain sensor signal to a single-chip microcomputer MCU; the single chip microcomputer MCU has a comparison function and is used for comparing the received signal of the tubular strain sensor 2 with a set value and sending an alarm signal when the received signal deviates from the preset range of the set value.
When the tubular strain sensor 2 is a fiber grating strain sensor, the tubular strain sensor 2 outputs an optical signal, and the adopted signal acquisition processing module has a photoelectric conversion function; when the tube-type strain sensor 2 is a strain sensor based on the resistance strain gauge principle, the tube-type strain sensor 2 outputs a voltage signal, and the adopted signal acquisition and processing module has an A/D conversion function.
Referring to fig. 2, fig. 2 is a schematic view showing a structure of the bolt of the present invention when the bolt 1 installed in the pipe type strain sensor 2 is installed on a fastening member such as a flange, and the fastening member is fastened by applying a rated torque. At this time, the bolt 1 is stressed to be elongated, when the fastening force of the bolt 1 reaches the preset moment, as an initial stage, at this time, the signal of the tubular strain sensor 2 is the elongation for fastening a normal bolt. Along with the alternating action of mechanical motion, vibration, temperature change and the like, the tightness of the bolt 1 is gradually reduced, and the output signal value of the tubular strain sensor 2 is also gradually reduced; and when the strain signal deviates from the preset range of the elongation signal of the fastening normal bolt, sending an alarm prompt.
Referring to fig. 3, fig. 3 is a schematic structural diagram of the high-strength bolt tightness on-line detection device after expansion, and the high-strength bolt tightness on-line detection device can be further expanded into an on-line detection system. The on-line monitoring system adopts a bus structure and is divided into three layers: the system comprises a field detection layer, a communication management layer and a background data analysis layer. The on-site detection layer has a signal acquisition and processing function, transmits a detected strain value to a communication management machine of the communication management layer in real time through a network, and transmits stress information to the background data analysis layer of the central control room through an optical fiber according to a standard protocol. The background data analysis layer realizes the storage and analysis of each point data to be monitored, adopts methods such as contrastive analysis, trend analysis and D-S evidence reasoning to realize the comprehensive judgment of the bolt fastening condition and the loosening degree, and provides the comprehensive judgment for operation and maintenance personnel to realize the state maintenance.
The above-mentioned contents are only for illustrating the technical idea of the present invention, and the protection scope of the present invention is not limited thereby, and any modification made on the basis of the technical idea of the present invention falls within the protection scope of the claims of the present invention.

Claims (8)

1.一种高强螺栓紧固度的在线监测装置,包括螺栓(1),螺栓(1)内固设有管型应变传感器(2),管型应变传感器(2)的信号传输线(4)延伸到螺栓(1)外,位于螺栓(1)外部的信号传输线(4)连接有信号采集处理模块,信号采集处理模块与单片机MCU相连;1. An on-line monitoring device for the tightness of a high-strength bolt, comprising a bolt (1), a tubular strain sensor (2) fixed in the bolt (1), and a signal transmission line (4) of the tubular strain sensor (2) extending Outside the bolt (1), a signal transmission line (4) located outside the bolt (1) is connected with a signal acquisition and processing module, and the signal acquisition and processing module is connected with the single-chip MCU; 所述信号采集处理模块用于接收管型应变传感器(2)的信号,转换成数字信号发送给单片机MCU;The signal acquisition and processing module is used for receiving the signal of the tubular strain sensor (2), converting it into a digital signal and sending it to the single chip MCU; 所述单片机MCU用于将接收到信号与设定值进行比较,当接收的信号偏离设定值预设范围时,则发出报警信号。The single chip MCU is used for comparing the received signal with the set value, and when the received signal deviates from the preset range of the set value, an alarm signal is issued. 2.根据权利要求1所述的高强螺栓紧固度的在线监测装置,其特征在于,所述螺栓(1)的一端设有六角凸缘(101),靠近六角凸缘(101)侧的螺栓(1)设有开设有安装孔,安装孔内设有螺纹;2. The on-line monitoring device for the tightness of high-strength bolts according to claim 1, wherein one end of the bolt (1) is provided with a hexagonal flange (101), and the bolt on the side close to the hexagonal flange (101) (1) It is provided with a mounting hole, and the mounting hole is provided with a thread; 管型应变传感器(2)的外壳上设有螺纹,管型应变传感器(2)通过螺纹配合设在安装孔内,所述信号传输线(4)通过六角凸缘(101)延伸到螺栓(1)外。The outer shell of the tubular strain sensor (2) is provided with threads, the tubular strain sensor (2) is arranged in the mounting hole through threaded fitting, and the signal transmission line (4) extends to the bolt (1) through the hexagonal flange (101) outside. 3.根据权利要求2所述的高强螺栓紧固度的在线监测装置,其特征在于,所述安装孔内设有封闭用的耐候胶(3)。3 . The on-line monitoring device for the tightness of high-strength bolts according to claim 2 , wherein the installation hole is provided with weather-resistant glue ( 3 ) for sealing. 4 . 4.根据权利要求1、2或3所述的高强螺栓紧固度的在线监测装置,其特征在于,螺栓(1)的螺杆(102)外围设有螺纹。4. The on-line monitoring device for the tightness of high-strength bolts according to claim 1, 2 or 3, characterized in that the screw (102) of the bolt (1) is provided with threads on the periphery. 5.根据权利要求4所述的高强螺栓紧固度的在线监测装置,其特征在于,管型应变传感器(2)与螺栓(1)焊接为一体。5 . The on-line monitoring device for the tightness of high-strength bolts according to claim 4 , wherein the tubular strain sensor ( 2 ) and the bolt ( 1 ) are welded integrally. 6 . 6.根据权利要求1所述的高强螺栓紧固度的在线监测装置,其特征在于,所述管型应变传感器(2)为光纤光栅型应变传感器,则对应的信号采集处理模块具有光电转换功能。6 . The online monitoring device for the tightness of high-strength bolts according to claim 1 , wherein the tubular strain sensor ( 2 ) is a fiber grating strain sensor, and the corresponding signal acquisition and processing module has a photoelectric conversion function. 7 . . 7.根据权利要求1所述的高强螺栓紧固度的在线监测装置,其特征在于,所述管型应变传感器(2)为电阻应变型应变传感器,则对应的信号采集处理模块具有A/D转换功能。7. The on-line monitoring device for the tightness of high-strength bolts according to claim 1, wherein the tubular strain sensor (2) is a resistance strain type strain sensor, and the corresponding signal acquisition and processing module has an A/D conversion function. 8.根据权利要求1所述的高强螺栓紧固度的在线监测装置,其特征在于,所述螺栓(1)外设有紧固件;8. The on-line monitoring device for the tightness of high-strength bolts according to claim 1, wherein the bolts (1) are provided with fasteners; 当螺栓(1)的紧固力达到预设力矩时,此时,管型应变传感器(2)输出信号对应螺栓(1)正常的伸长量;When the tightening force of the bolt (1) reaches the preset torque, at this moment, the output signal of the tubular strain sensor (2) corresponds to the normal elongation of the bolt (1); 随着机械运动、振动、温度变化的交变作用,螺栓(1)的紧固度降低,管型应变传感器(2)的输出信号随之降低;With the alternating action of mechanical movement, vibration and temperature change, the tightness of the bolt (1) is reduced, and the output signal of the tubular strain sensor (2) is reduced accordingly; 当管型应变传感器(2)输出信号偏离螺栓(1)正常的伸长量的信号的预设范围时,则发出报警信号。When the output signal of the tubular strain sensor (2) deviates from the preset range of the signal of the normal elongation amount of the bolt (1), an alarm signal is issued.
CN202011315596.6A 2020-11-21 2020-11-21 On-line monitoring device for high-strength bolt tightness Pending CN112304236A (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113029420A (en) * 2021-03-05 2021-06-25 上海理工大学 Embedded wireless passive bolt tightness state monitoring system based on surface acoustic wave technology
CN114061819A (en) * 2021-10-20 2022-02-18 广州建筑股份有限公司 A scaffolding fastener tightening torque monitoring device
CN114318415A (en) * 2022-01-11 2022-04-12 青岛双瑞海洋环境工程股份有限公司 Anti-dismantling early warning system and method for electrolytic cell
CN115307537A (en) * 2022-09-15 2022-11-08 雅砻江流域水电开发有限公司 Hydraulic generator foundation bolt intelligent monitoring system

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113029420A (en) * 2021-03-05 2021-06-25 上海理工大学 Embedded wireless passive bolt tightness state monitoring system based on surface acoustic wave technology
CN114061819A (en) * 2021-10-20 2022-02-18 广州建筑股份有限公司 A scaffolding fastener tightening torque monitoring device
CN114318415A (en) * 2022-01-11 2022-04-12 青岛双瑞海洋环境工程股份有限公司 Anti-dismantling early warning system and method for electrolytic cell
CN115307537A (en) * 2022-09-15 2022-11-08 雅砻江流域水电开发有限公司 Hydraulic generator foundation bolt intelligent monitoring system

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