Operating principle
DiagBelt: magnetic method
As part of the project, DiagBelt+ has been successfully implemented in the Bełchatów lignite coal mine, confirming its effectiveness in real industrial conditions. The magnetic method, which constitutes the core functionality of the system, is based on magnetizing the cords in the core of the belt and monitoring their magnetic properties. During measurement, changes in the magnetic field generated by the magnetized core of the belt are recorded. In the case of defects such as cracks or changes in magnetic properties, a change in the magnetic field occurs, allowing their detection by inductive sensors in the measuring head.
DiagBelt+ uses a measuring head consisting of 90 coils evenly spaced every 25 mm. Additionally, the system is equipped with two strips of permanent magnets placed above and below the belt at the appropriate distance (about 30 mm) from its covers. During measurement, the system analyzes changes in the magnetic field, enabling non-invasive and precise assessment of the technical condition of the belt core. This solution contributes to the effective monitoring of conveyor belts, leading to increased reliability and safety of material transport systems.
Real-time monitoring
Monitors key parameters in real-time, reacting quickly to any changes.
Versatility of Applications
A universal solution tailored to various industries and needs, from industrial applications to scientific research.
Resistance to Conditions
Robust construction and independent mounting of measurement head ensure resistance to vibrations and impacts.
High Measurement Resolution
DiagBelt+ utilizes 90 inductive sensors, ensuring continuous and precise measurement with high resolution both longitudinally and transversely.
Fault Detection
Immediate detection and signaling of potential issues, minimizing the risk of downtime and losses.
Assessment of Conveyor Construction Integrity
The distribution of damages across the cross-section of the conveyor belt allows for an evaluation of the correctness of material feeding onto the belt.
Analysis and Reporting
Precise data analysis and report generation, enabling informed decision-making.
The diagram and dimensions of the DiagBelt+ system
The mounting of the measurement head
The mounting of conditioning heads
DiagBelt+ is a conveyor belt diagnostic system that utilizes a magnetic method for the precise assessment of the technical condition of the belt core. The primary principles are based on monitoring the magnetic properties of the cords in the belt core.
In practice, the DiagBelt+ system requires the installation of permanent magnet strips (conditioning heads) above and below the belt. These magnetic strips magnetize the cords in the belt core. In areas of discontinuity, such as cracks or changes in magnetic properties, a scattered flux occurs. Ninety inductive sensors installed in the measuring probe head measure changes in the magnetic field at the points of cord discontinuity. The system operates at a frequency of 400 Hz, resulting in a measurement resolution of 2.5 mm at a belt speed of 1 m/s. The distance between sensors is 25 mm. Measurement results allow for the identification of the location and characteristics of damage, providing essential support in planning maintenance and repairs of conveyor belts.
The project has been implemented in the lignite coal mine KWB Bełchatów, confirming the effectiveness of this diagnostic method. The DiagBelt+ system enables effective monitoring of the technical condition of conveyor belts, contributing to increased reliability and efficiency of conveyor transport.
Review the contents of a sample research report
A comprehensive picture of the technical condition of the examined conveyor belt with steel cords can be obtained through the collaborative operation of both devices (DiagBelt and BeltSonic). Their joint operation has been tested in the Conveyor Transport Laboratory (LTT) as well as in industrial conditions.
Visualization of core failures
The visualization of core failures in the conveyor belt using the DiagBelt system is based on the bipolarity of the installed coils in the measurement head.
Damage to the cords, such as breakage, missing cords, cutting, corrosion, or crushing, as well as the presence of measurement splices or performed repairs, generates characteristic magnetic signals. Each type of damage has a distinct signal characteristic.
In practice, the size of the damage, the distance of the measuring probe head from the belt, the belt speed, and the selected sensitivity threshold influence the differences in damage signals. Years of practical application of the magnetic method have allowed for the precise adjustment of measurement parameters to specific belt operating conditions.
Minor failures, such as partial cord damage, generate small signals visible as a cluster of blue points recorded on several measurement channels. As the size and complexity of the damage increase, the recorded magnetic field change enlarges, and two clusters of points with opposite polarization of the magnetic field change appear (yellow point clusters). Ultimately, on the image depicting the location of the damage, only the central cluster of points (blue color) indicates the precise location of the discontinuity.
In the case of identifying repairs, the recorded signal has the opposite polarization, and the location of its occurrence is indicated by a cluster of yellow points (similar to the splice signal but not occurring across the full width of the belt).
Color-coded map of the technical condition
A visual representation of belt sections with assigned colors, in accordance with the scale of core wear based on a chosen metric (e.g., core damage density per section or density of the signal field surface for damages per section), enables immediate identification of sections with varying degrees of wear.
This visualization allows for a quick and efficient assessment of the belt’s technical condition based on colors. The color scale facilitates accurate classification of belt sections in terms of their condition, contributing to the identification of areas requiring special attention.
The color-coded map of the belt’s technical condition serves as a tool for making decisions related to maintaining belts in good technical condition.
Prediction of Remaining Conveyor Belt Operating Time
With cyclical measurements of the conveyor belt core’s condition over time, it is possible to establish a prediction curve for the rate of new damage occurrences. This tool provides valuable insights into the dynamics and pace of damage accumulation over time.
The “0” point on the curve is based on the date of the first belt installation— at that time, the belt should have 0 damages. Subsequent measurements contribute to building a curve that becomes increasingly representative and accurate as more data accumulates. In other words, the more measurements taken, the more reliable the prediction curve becomes as an analytical tool.
The prediction curve of damage density increment not only aids in understanding the current technical condition but also facilitates forecasting future wear. This is crucial for making informed decisions regarding maintenance, repair, or replacement of belts. The method allows for a precise assessment of the impact of operation on the belt’s technical condition, supporting a measurement-based approach in making key operational decisions. It is also possible to determine the point at which the belt will reach a specified critical density threshold, qualifying it for dismantling for recycling or refurbishment.
Analysis of the technical condition of belt splices
One of the system’s functions is the assessment of belt splice quality, enabling the identification of potential issues.
Using the magnetic method, DiagBelt+ allows for the diagnostics of various types of steel cord belt splices, including straight, stepped, single-step, and multi-step splices. The system also enables the measurement of splice length, the length of individual steps, and the skewness coefficient of inclined splices (which, according to standards, should range between 0.2 and 0.3 of the splice width).
Through regular diagnostics of belt splices with the DiagBelt+ system, it is possible to eliminate potential defects and monitor the splice condition over time to detect developing trends, such as splice separation.
Złącze dwustopniowe, proste
Złącze jednostopniowe, proste
Analysis of the belt cross-section
The DiagBelt system enables the analysis of damage distribution across the belt width, allowing for the examination of belt cross-sections and the assessment of chute design correctness.
Thanks to the dense measurement grid of the sensor head, the system records magnetic signals in multiple parallel channels covering the entire belt width. This makes it possible to create cross-sectional maps of core damage, showing the characteristic distribution of defects for a given section of the conveyor.
The distribution of damage across the belt reflects the way in which the transported material interacts with its surface. A concentration of defects in the central part of the belt may indicate an excessively focused material stream during loading, while an asymmetric pattern (a higher number of defects on one side) may point to uneven chute feeding or improper outlet positioning.
The analysis of these cross-sections allows for the evaluation and optimization of chute geometry, impact angle, and the method of material loading onto the belt. As a result, it helps reduce the concentration of dynamic loads, extend belt lifespan, and minimize the risk of core damage.
Cross-sectional visualization is particularly useful in identifying areas of excessive material impact, as well as in evaluating the effectiveness of structural modifications made to the loading system.