First Knife

The Pre-cutting bit is the first tool to contact and excavate the soil. It cuts a series of circular rings along the radial direction of the tunnel face to loosen the soil in advance, which can significantly improve the fluidity of the soil layer, reduce the cutting resistance of the scraper, and provide favorable conditions for the scraper to cut and collect slag. This in turn enhances the excavation efficiency and reduces damage to the scraper. The Pre-cutting bit exhibits excellent adaptability in highly weathered formations and weakly cemented sandy gravel formations.