Design of Disc Cutter Wear Test System and Research on Wear Law Based on Eddy Current Testing Technology

As the primary rock-breaking tool of the tunnel boring machine (TBM), the disc cutter experiences significant wear from the immense cutting load. Given the intricate geological conditions in TBM excavation, accurately assessing the extent of wear on disc cutters solely through experience and predictive models is challenging. Therefore, implementing synchronous wear monitoring when a disc cutter breaks rock to accurately assess the amount of wear on the disc cutter and determine the point at which a tool change is needed is extremely important. In this work, a disc cutter wear test system is designed on the basis of the principle of eddy current testing and the variation in disc cutter wear during cutting is revealed through experiments. The radial reduction rate (Dr) is used as an index of disc cutter wear to analyze the variations in penetration, cutting speed, the cutting resistance coefficient (Cc), and specific energy consumption (SE) in relation to disc cutter wear. The experimental results indicate that the measurement error of the disc cutter wear testing system is 8.6%, which allows disc cutter wear level to be obtained. With increasing cutting displacement, the Dr of the disc cutter first increases rapidly but then slows. The Cc of the disc cutter increases exponentially with increasing Dr under different penetration depths. When the cutting displacement of the disc cutter reaches 40 m, Dr exhibits an exponential growth trend with increasing cutting speed. The critical value of Dr is 0.084. When Dr exceeds this value, the cutting performance exhibits a sharp increase in torque, which significantly impacts the driving efficiency. The research results of this paper provide a reference for creating a disc cutter replacement plan and extending the service life of the disc cutter. Optimized design of a disc cutter wear test system based on eddy current detection.The radial reduction rate is proposed as an indicator of disc cutter wear.The critical value for disc cutter replacement is explored and revelled.