ROCK BIT CONE AND METHOD OF MANUFACTURING THE SAME

摘要

A rock bit cone having a substantially conical body (1) on a surface of which a number of teeth (2) are formed is manufactured by pressure-casting with using a casting mold (10, 20, 30) having a molding surface including a cone body defining surface portion (12, 32) and tooth defining surface portions (13, 33) pressure-casting with using the same casting mold having separately prepared inserts (3) supported on the respective tooth defining surface portions (33) or pressure casting, with using the same casting mold, firstly the teeth (2) with a hard metal and secondly the cone body (1) with a tough metal. A resultant product is machined to form a bearing portion (4). The insert (3) has a root portion (3a) equiped with an anti-dropout means.