CN2281412Y

CN2281412Y - Stable PDC drill bit

Info

Publication number: CN2281412Y
Application number: CN 96250942
Authority: CN
Inventors: 王福修; 王锡州
Original assignee: DRILLING TECHNOLOGY INST SHENGLI PETROLEUM ADMINISTRATION
Current assignee: DRILLING TECHNOLOGY INST SHENGLI PETROLEUM ADMINISTRATION
Priority date: 1996-12-26
Filing date: 1996-12-26
Publication date: 1998-05-13
Anticipated expiration: 2006-12-26

Abstract

The utility model belongs to the structure improvement on a PDC drilling bit which is used for the oilfield well drilling and the geologic well drilling. A cutter wing is made into a spiral of an Archimedes spiral shape, and is in a uniform-distributed structure. Three to six PDC cutting teeth are arranged on the same drilling-bit diameter part on the cutter wing. Thereby, the probability of generating the vibration of the drilling bit is reduced, or the vibration degree of the drilling bit is reduced. The stability of the drilling bit is raised, and the shock resistance is reinforced. The utility model can smoothly drill in the hard formation, the mechanical drilling speed and the life time are raised, and the drilling cost is saved.

Description

A kind of stable type PDC drill bit

The utility model belongs to the architecture advances of oil, geological drilling usefulness PDC drill bit.

Conventional PDC drill bit has advantages such as rate of penetration is fast, the life-span is long in soft formation, but creeps into poor performance in than hard formation.Its reason is that the wing of conventional PDC drill bit is linearly and along circumferentially evenly distribution of drill bit, a PDC cutting teeth is only installed at the same diameter place of bit face, and overlap coefficient is bigger between the cutting teeth.Thereby poor stability when causing drill bit to creep in than hard formation a little less than the impact resistance, causes that the PDC cutting teeth is cracked, and the drill bit rate of penetration reduces.

The purpose of this utility model provides the PDC drill bit of a kind of stability height, strong shock resistance.When conventional PDC drill bit creeps in than hard formation a little less than poor stability, the impact resistance.Wing of the present utility model is processed into the spiral of Archimedes shape and is non-uniform Distribution on the drill bit circumferencial direction, has reduced drill bit whirling vibration odds or has reduced the drill vibration degree.3 to 6 PDC cutting teeths are installed at same bit diameter place on wing, form the rock protruding ring in the shaft bottom when creeping into, and have stoped the generation of drill bit oscillation crosswise.Thereby stability improves greatly, impact resistance strengthens, and creeping into performance in than hard formation has improvement greatly.

A kind of stable type PDC drill bit mainly is made up of bit body, PDC cutting teeth, wing, nozzle and chip area.Wing on the bit body end face is processed into the spiral of Archimedes shape, and is the non-uniform Distribution structure.3 to 6 PDC cutting teeths are installed at same bit diameter place on the wing.Figure of description:

Fig. 1. stable type PDC bit face schematic diagram

Description of drawings:

1. bit body 2.PDC cutting teeth 3. wings

4. nozzle 5. chip areas

Now the utility model will be further described in conjunction with Figure of description:

In drilling process, at first the utility model and other down-hole equipment are coupled together, at the bottom of the lower going-into-well, turn on pump circulating fluid pressurization rotary drilling then.Because wing of the present utility model [3] is processed into the spiral of Archimedes shape, make power that drill bit presents situation less than the straight knife wing on the direction perpendicular to the borehole wall, reduced the contact stress between the bit gauge protection and the borehole wall, gone up the possibility of certain some rotation (being whirling vibration) around protecting the footpath thereby reduced drill bit.Wing of the present utility model [3] is gone up the same diameter of drill bit place 3 to 6 PDC cutting teeths [2] is installed, form a plurality of cutting teeth donuts, and the overlap coefficient of PDC cutting teeth [2] is very little between each donut, therefore in drill bit rotary drilling process, produce rough shaft bottom, make and form the rock protruding ring between the adjacent cutting tooth donut.When drill bit caused eccentric rotation for a certain reason, PDC cutting teeth [2] is the contiguous rock protruding ring of bump just, and this effect produces a stability force opposite with eccentric direction, has stoped the generation of drill bit oscillation crosswise.If certain cause specific has caused that drill bit vibrates, but because wing of the present utility model [3] right and wrong on the drill bit circumferencial direction are equally distributed, and this structure can be broken cycle or the frequency of keeping vibration, thereby extent of vibration is reduced.Because the utility model adopts above-mentioned vibration damping or stabilizing measures, having reduced drill bit the probability of vibration takes place or has reduced extent of vibration, thereby stability of bit and impact resistance have been improved, the utility model is steadily crept in than hard formation, it is fast to bring into play its rate of penetration, the advantage of life-span length is saved drilling cost.

Claims

1. stable type PDC drill bit, mainly form by bit body [1], PDC cutting teeth [2], wing [3], nozzle [4] and chip area [5], it is characterized in that the wing [3] on bit body [1] end face is processed into the spiral of Archimedes shape, and be the non-uniform Distribution structure.

2. stable type PDC drill bit according to claim 1 is characterized in that going up same bit diameter place at wing [3] installs 3 to 6 PDC cutting teeths [2].