... We can also supply drag bits,drill pipe,drill collar, DTH hammer bits, fishing tools, stabilizer, casing centralizer, floatshoe&float ... better prices2.production introductionTCI tricone bit, tci roller Bits ,roller bit,steel tooth roller bit,TCI roller bit,TCI tricone bit437Soft Formation ... used in the outer rows to prevent loss of bit gauge. Maximum numbers of hemispherical-shaped inserts are used ...