In view of the difficulty in inspecting and monitoring steel-cord conveyor belts in coal mine transportation, TCK has successfully solved the problem of online automatic monitoring of steel-cord conveyor belts by using weak magnetic detection technology, combined with modern network communication technology, computer technology, explosion-proof technology, and other modern cutting-edge scientific and technological achievements.

　　1 overview

　　The steel-cord conveyor belt is an important transportation equipment in the field of coal mine production. In practical work, it is restricted by various hidden factors such as Joint twitching rope core fracture, corrosion, etc., which further cause the steel-cord conveyor belt to break down. Therefore, it is particularly important to detect the hidden dangers of steel-cord conveyor belt. Jizhong Energy Co., Ltd. Xingtai Mine is a mine with an annual output of 1.95 million tons. The second strong belt is responsible for the throat route of underground raw coal transportation. Once an accident occurs, it will directly affect the transportation task of raw coal and cause great harm to the mine. Therefore, the operation status of the second strong belt has always been highly concerned by managers.

　　Currently, daily maintenance and inspection work on steel-cord conveyor belt is carried out by using manual visual inspection method and auxiliary instrument detection method, which has the disadvantage of time delay and production impact. Therefore, it is particularly important to study an online, real-time and automatic detection system for steel-cord conveyor belt.

　　As an advanced detection technology, TCK online real-time automatic monitoring system for steel-cord conveyor belt integrates network communication, computer software, explosion-proof function, etc. This detection system proposes a new solution for safety supervision. It can accurately detect the movement and displacement of steel wire rope core in conveyor belt, as well as hidden dangers such as broken rope, fatigue, corrosion and other factors that may lead to conveyor belt failure accidents. It effectively solves the technical problems of detecting hidden dangers in conveyor belt.

　　2 Basic principles of weak magnetic detection

　　The steel wire rope in the tape is made of high-quality steel and has good magnetic conductivity. When the steel wire in the steel wire rope core conveyor belt is magnetized, an induced magnetic field Bz1 is generated on the surface of the steel wire rope, which is opposite to the direction of the defect magnetic induction intensity. When the sensor comprehensively processes the magnetic induction intensity, the main leak magnetic induction intensity Bz1 is offset by using the step magnetic induction intensity vector Bb.

　　For the sensor coil, the magnetic induction intensity captured at a certain point is the axial component vector sum of various magnetic induction intensities at that point on the steel wire rope outer surface, which can be expressed as: As shown in the figure. In the formula: respectively represent the magnetic induction intensity captured by the sensor coil, the main leak magnetic induction intensity, compensation magnetic induction intensity, environmental magnetic induction intensity, offset magnetic induction intensity, broken wire leak magnetic induction intensity, wear leak magnetic induction intensity, rust leak magnetic induction intensity, fatigue leak magnetic induction intensity, deformation leak magnetic induction intensity, the nth magnetic induction intensity vector, and any defect magnetic induction intensity.

　　Experiments have shown that the output signal U of the sensing coil is a function of Bs, and the equivalent defect △S is a function of U, as shown in the figure. In the equation, U represents the voltage signal output by the sensing coil, as shown in the figure. In the equation, △S, A, and C represent the equivalent defect or percentage of loss area, the proportional coefficient, and the constant, respectively. In this case, the area loss value △S of the damaged point of the steel wire rope core becomes a function of the field intensity Bi.

　　The TCK.W steel cord conveyor belt line storage real-time monitoring system, as a detection device, mainly uses a modular sensor array with horizontal and vertical response. For horizontal sensors, due to their ability to sensitively sense the distribution characteristics of metals, the amplitude output of the steel cord core breakage (including joints), fatigue, rust corrosion, and other signals can be quantified to improve the detection accuracy. For vertical sensors, due to their sensitivity to the motion characteristics of metal distribution, such as joints, breakage, and other signals, the steep waveform improves the reliability of positioning detection. It fully ensures the positioning and quantitative detection performance of the detection.

　　3 System composition and workflow

　　The TCK-GMS weak magnetic loading device, TCK-GMS flaw detection device, TCK-GMS travel encoder, self-controlled acoustic and optical alarm device, TCK-message reporting function device, and TCK terminal main control device jointly constitute the TCK steel wire rope core conveyor belt online real-time automatic monitoring system. In this system, the magnetic induction sensor array box, data acquisition, communication module, multi-output explosion-proof and intrinsic safety power supply, etc. are composed of the TCK-GMS flaw detection device. These components are integrated in the combined sensor box and installed at the bottom of the conveyor's downward rubber belt. For the sensor box, it is equipped with multiple magnetic induction sensors, each of which can monitor a certain number of steel wire ropes. During the operation of the conveyor, the steel wire rope core in the conveyor belt is continuously scanned. In the scanning process, if there is any headbreak, corrosion, damage or sulfurization joint pull-in phenomenon, the sensor will emit an electrical signal at the fault site. The magnetic induction sensors and other information are collected in real time by the data acquisition module, and the collected information is transmitted to the TCK terminal main control device in the ground monitoring room through the mine industrial Ethernet network using the communication module and multi-output. The software system compares and queries current data, basic data and historical data, scans the fault type in real time, and calculates the value. The detection system has functions such as data statistics, automatic alarming, detection result printing and remote transmission. Its working process is shown in Figure 1.

　　4 System Functions

　　4.1. Non-contact detection of the steel cord conveyor belt can be carried out without affecting the operation of the conveyor belt, reducing the time of power outage for maintenance and improving the transportation efficiency.

　　4.2. The steel cord conveyor belt can carry out online automatic locking and provide functions such as detection results display, acoustic-optical alarm, automatic printing of detection reports, etc.

　　4.3. It can detect various injuries such as broken cores, wear and corrosion of steel cord in the non-joint area of the steel cord conveyor belt through quantitative and positioning methods.

　　4.4. It can carry out unmanned and 24/7 continuous online automatic monitoring.

　　4.5. It can extract, convert, process and store the whole state information of the steel cord conveyor belt being detected, and provide detection analysis reports at the same time.

　　4.6. The TCK dedicated software technology has a Chinese interface, dialogue-style operation, data analysis, real-time image reconstruction, real-time pressure plate storage, and historical data review and query.

　　5 Technical characteristics of the system

　　5.1 High Resolution

　　Instant detection accuracy of 1mm, able to accurately and effectively identify the elastic and permanent displacements of steel cord conveyor belt splice.

　　5.2 High Sensitivity

　　The 5V/Gs high-sensitivity magnetic induction sensor invented by TCK can quantitatively detect early safety hazards such as joint pull-out, internal broken rope, and fatigue corrosion.

　　5.3 Precise Positioning

　　The system uses a horizontal + vertical II directional response combined "sensor spatial array" to accurately locate the two-dimensional plane of internal damage of steel cord conveyor belt.

　　6 System software flowchart

　　7 Main performance indicators

　　①
Sensor sensitivity modulation range: A = 2.5 ~ 5V/G.

　　②
Distance between the detector and the surface of the conveyor belt being measured: 50 ~ 110mm.

　　③
Sampling response frequency: 8kHz.

　　④
. Geological mining.

　　Data transmission rate: 10M门OOMbps adaptive.

　　⑤
Position detection resolution: 1mm.

　　⑥
Accuracy of steel cord fatigue and corrosion detection: >90%.

　　⑦
Accuracy of joint displacement detection: >95%.

　　⑧
Accuracy of internal broken core detection: 99%.

　　⑨
Fault location error:

　　In the direction of belt length: 4-100mm

　　In the direction of belt width: 4-50mm.

　　8 conclusion

　　Xingtai Mine of Jizhong Energy Group actively promotes the innovation of safety management of transportation equipment, and has installed an online real-time automatic monitoring system for TCK steel wire rope conveyor belts on the Erqiang belt, effectively addressing potential safety hazards on steel wire rope conveyor belts.

　　The operation of the TCK steel wire rope core belt conveyor online monitoring system in Xingtai Mine's Erqiang Belt shows that the system has the function of real-time online automatic monitoring of the damage points or joints of the steel wire rope core in the conveyor belt, and real-time monitoring of the changing state of key hidden dangers. The detection data can be queried, viewed, and compared and analyzed through options such as date and joint location, providing intuitive judgment for maintenance personnel and providing a reliable basis for leadership decision-making. The application of this system has changed the past manual inspection mode, completing the detection while production, reducing the labor intensity of workers, and reducing the downtime for maintenance.