The top of the tricone bit can be maintained a little bit more complex: a little bit of the beginning is not simple, composite plate type a little start to look at the outside can also be embedded with diamond diameter, more and more wear-resistant, the characteristics of the diameter is also very complex, can make the cutter can also be easily selected under certain conditions; It has been proved that it can be applied to the progress of soft and medium hard strata, such as carbonate rock, limestone, chalk, claystone, siltstone, sandstone, etc. Compared with ordinary bit of tricone bit, especially in the drilling of 6-8 strata, the effect is obvious; The maintenance of the tricone bit will certainly not be the same in the drilling speed more and more easy about the years of more and more long-term use, this point there is a little bit of drilling these two pieces above the possibility of getting better and better, a little bit of the start of drilling the top of the principal yellow again, under certain conditions with comparative excellent characteristics.