FERRAMENTA CORTANTE,BROCA DE PERCUSSAO PARA ROCHA E INSERCAO DE CARBONETO CEMENTADO PARA FERRAMENTA CORTANTE

摘要

In a percussive rock bit or similar tool wherein cemented carbide cutting inserts are retained in open radial slots in the head of the tool, an improved method of mechanically retaining the inserts. The inserts are provided with a plurality of elongated radially aligned serrulations along each flank thereof, the thickness of the insert as measured between the crests of opposing serrulations being such as to provide a substantial interference with the slot wall. The inserts may be cold fitted by sliding along the slot, following which body material is peened so as to overlay a small chamfer at the base of the outwardly facing wall of the inserts. The inwardly facing walls of the inserts may be inclined so as to retain the center plug of the rock bit mechanically.