Abstract:Sand conglomerate formation is a difficult drilling stratum in drilling engineering, how to improve the drilling efficiency and bit service life in sand conglomerate stratum have been the important problem in engineering practice. In view of the problems of early breaking of common cone bit outer teeth and low comprehensive use index in the drilling process of Zhenzhuchong quartz sand conglomerate strata in Yuanba area, the stratigraphic lithology, drill bit usage and failure are analyzed, and especially aiming at the bit cutting structure, tooth material optimization and bit gauge retaining strengthening, new HJT547GKL tri-cone drill bit is optimally designed and developed. Field test result shows that this new type of cone bit has high stroke footage in Zhenzhuchong formation of Yuanba area, which is reliable, practical and suitable for hard formations and formations with hard interlayer drilling with simple structure and good gauge retaining.