A six-point positioning concave three-wing pdc non-coring bit structure and its diameter-keeping method

Abstract

The invention discloses a six-point positioning inwards recessed three-wing PDC noncoring bit structure and a gauge protection method of the six-point positioning inwards recessed three-wing PDC noncoring bit structure. A noncoring bit comprises a drill bit blank body and a drill bit steel body, wherein a cutter wing part, a center inwards recessed part, a drill bit body gauge protection part, a spray nozzle, a flow passage and a discharging groove are arranged on the drill bit blank body, the cutter wing part comprises three cutter wings, the three cutter wings of the drill bit blank body are sintered on the drill bit steel body through WC powder materials via a sand mold, a drill bit enters a groove to from a short cylindrical round core during the drill through the center inwards recessed part, PDC cutting teeth are fixedly arranged at the cutter wings and the center inwards recessed part, and the drilling of the drill bit into the broken stratum is ensured. The drill bit body gauge protection part is formed by circular arc sections with different diameters from the dill bit, the gauge protection back end is coincident with the drill bit diameter, the drill bit spray nozzle is directly formed on the drill body through a sand core rod, the center inwards recessed part and flow passages formed among the cutter wing parts are connected into a whole, and rock chips can be favorably discharged in time. Therefore the drill bit drilling stability is good, the mechanical drilling speed is higher, and the service life is longer.

Description

technical field [0001] The invention relates to a polycrystalline diamond (PDC) composite chip drill bit, in particular to a six-point positioning concave three-wing PDC non-coring drill bit structure and a diameter-keeping method thereof, belonging to the field of drilling tools. Background technique [0002] Polycrystalline diamond compact drill bit is a kind of diamond drill bit. Polycrystalline diamond compact drill bit is abbreviated as PDC. Polycrystalline diamond compact drill bit is also called PDC drill bit. Downhole gas drainage, water injection and drainage and other drilling rotary and impact rotary drilling and other fields. In the prior art, when drilling into medium-hard to hard fractured formations, drilling with cemented carbide bit has the quality problems of slow ROP, short service life and broken teeth, resulting in extra tripping operations and increased drilling time. Drilling time and operating costs are relatively high. Therefore, at present, the dr...

AI Technical Summary

Problems solved by technology

Although the PDC composite sheet of the PDC bit is hard and has a long wear-resistant service life, it is not impact-resistant. When drilling in medium-hard to hard fractured formations, the PDC composite sheet is prematurely broken and failed due to the vibration and impact of the drill bit, resulting in This kind of drill bit does not give full play to the advantages of long service life of the PDC composite drill bit, so it is urgent to improve the structure of the existing PDC composite drill bit to prevent the premature failure of the PDC composite drill bit, thereby improving the service life of the PDC drill bit

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