The use of magnetic sensors in monitoring the condition of the core in steel cord conveyor belts – Tests of the measuring probe and the design of the DiagBelt system

Abstract The DiagBelt system for monitoring the technical condition of conveyor belts comprises five modules: a vision module, a magnetic module, a prediction module, a rip detection (prevention) module, and a safety factor module. This article focuses on the magnetic module, which consists of the BeltGuardTM measuring probe and the DiagBelt application, the latter being used to process the digital signal produced by changing magnetic field generated around defects in the magnetized steel cord. Owing to the high resolution of the multi-coil measuring probe, it is possible to detect not only cuts of individual cords but also broken wires in the cords, and even the corrosion of cords in the core. The application automatically and precisely detects the location of defects along the belt axis and on the belt section (due to the position of the coil which traces the changes in the magnetic field). It also detects the location of all splices in the belt loop. This function allows the changes to be visualized as a 2D image of belt core defects on all belt sections and splices. The system automatically divides the belt into sections and counts the defects and their surface area, thus offering useful damage measurement units such as damage density or damage surface area per 1 running meter of belt. These in turn serve as the basis for a color-coded image showing the condition of belt loop sections in the DiagBelt system. Such comprehensive diagnostics of conveyor belts and their splices reduces the number of unexpected failures and facilitates the planning of maintenance works and of belt replacement procedures, thus contributing to improved conveyor belt management.