The Development And Application Of PDC Drilling Bit For Medium-Deep To Deep Formations

The research work of this thesis can be divided into two parts that one part is the designing theories research of the PDC drilling bit, and the other part is the manufacturing design of drilling bit. In the design theories research of the PDC drilling bit, it systematically study the adaptability between the crest shape of bit and geologic strata, the breaking rock function, arranging design, bit nozzle runner, and junk slot of the cutting gear. And it analyzes the characteristic of the PDC drilling bit of the parabola form, the fish tail form, the short parabola form and flat head crest shape. According to the theories of breaking rock and wearing of the PDC drilling bit, it researches the arranging of cutting gear and arranging density which influence to the drilling bit property. It puts forward the nozzle diameter, the nozzle shape, the arranging of nozzle, the runner structure, and the designing plan of the junk slot. In the making drilling bit design, at first make use of the embryo body blade structure, the blade to lengthen and a double row protects radial tooth technique, having designed to be applicable to the Daqing oil-field 1200m or so soft geologic stratum of three embryo body blade PDC drilling bit. On this base, making use of looking like the symmetry type in the long blade design and the in-outside conical hat department and the fan-shaped junk slot techniques, design to be applicable to the Daqing oil-field 1500m ～2200m of different block of soft and middle-hard geologic stratum go to in four-blade of the, five-blade and six-blade PDC drilling bit. A set of PDC of integrity drilling bit manufacturing project have be formed.