CN101492998B

CN101492998B - Radial shrink-proof single-cone rotary drill bit

Info

Publication number: CN101492998B
Application number: CN200910058490XA
Authority: CN
Inventors: 邓嵘; 郗海华; 黄沧沧; 魏刚
Original assignee: Southwest Petroleum University
Current assignee: Southwest Petroleum University
Priority date: 2009-03-03
Filing date: 2009-03-03
Publication date: 2011-06-29
Anticipated expiration: 2029-03-03
Also published as: CN101492998A

Abstract

The invention relates to a single roller bit used for drilling for oil fields, mining and geological exploration, mainly comprising a bit body and a roller cone; wherein the teeth distributing surface of the roller cone is a revolution surface which mainly comprises two main conical surfaces and three auxiliary conical surfaces or one curved surface and two conical surfaces. Axes of the revolution surface and axes of a roller cone bearing coincide and a section of bus of the revolution surface is symmetrical relative to a spin axis of the bit. The bit has the following advantages: motion mode of teeth is determined by shape of the roller cone and relevant structural parameters and the shape of the roller cone can be flexibly designed according to stratum lithology; the volume of the tip of the roller cone is large, so that teeth distributing area is enlarged and strength of the roller cone is enhanced; a bottom-hole central area formed by shattering rock by the bit is deeper than an exterior area, so that the front end of the roller cane is buried in the bottom-hole central area to prevent the bit from sliding towards the bottom-hole center, thereby achieving the purposes of stabilizing the bit motion and preventing hole diameter decrease.

Description

Radial shrink-proof single-cone rotary drill bit

Affiliated technical field

The present invention relates to the single-cone rotary drill bit that oil field, mining and geological prospecting drilling well are used.

Background technology

Single-cone rotary drill bit is made up of bit body and a gear wheel usually, bit sub is arranged on the bit body, tooth pawl and gear claw journal etc., be installed with the tooth of energy fractured rock on the gear wheel, bit sub and top screw thread are used for making drill bit to link to each other with drilling rod, tooth pawl and gear claw journal are to support and drive the carrier of gear wheel around the rotation of drill bit rotation, and gear wheel and top tooth thereof are the body element of drill bit fractured rock.

Except that spherical single-cone rotary drill bit, the single-cone rotary drill bit that use early stage is not to meet the eye on every side drill bit, and gear wheel can not occupy space, whole shaft bottom.When rock was broken in the drill bit rotation under the pressure of the drill effect, because the distortion of the transverse bending of drill bit and drill string, drill bit will be more or less to the slippage of well center, causes hole shrinkage, made the borehole diameter that gets out less than setting.

Summary of the invention

The motion mode of single-cone rotary drill bit is mainly determined by the profile and the dependency structure parameter of its gear wheel.The bottom hole pattern that the single-cone rotary drill bit of different gear wheel shapes and structural parameters forms is different, and is also different in the stressed and broken rock mode in shaft bottom.Technical problem to be solved by this invention is to adopt certain suitable gear wheel shape, reaches to make drill bit movement stable, prevents the purpose that hole diameter dwindles.

In order to achieve the above object, the present invention by the following technical solutions: single-cone rotary drill bit mainly is made up of a bit leg (1) and a gear wheel (2), is installed with the tooth of energy fractured rock on the gear wheel, and gear wheel is assemblied on the bit leg journel, and can rotate flexibly.Gear wheel mainly is made up of the conical surface and curved surface.Drill bit drives gear wheel around axis (4) rotation and rotates and fractured rock around bearing axis (3).The central area, shaft bottom that the broken rock of drill bit forms is darker than the exterior zone, makes the front end of gear wheel imbed the central area, shaft bottom, stops drill bit to the well off-centring, plays stable drill bit movement, prevents the effect that hole diameter dwindles.

The present invention has changed the shaft bottom profile, the central area, shaft bottom that the broken rock of tooth of gear wheel fore-end is formed is darker than the exterior zone, and the front end of drill bit gear wheel when the broken rock of motion is imbedded the central area all the time, forms a neck, stoped drill bit to the slippage of well center, prevented that hole diameter from dwindling.The shaft bottom is stairstepping simultaneously, has increased the scope of freedom of rock, helps improving the crushing efficiency of rock.Gear wheel has adopted hierarchic structure, and it is bigger that gear wheel is taken turns sharp volume, increased the cloth toothed area, improved gear wheel intensity.

Description of drawings

Fig. 1 is one embodiment of the present of invention figure

Fig. 2 is the gear wheel outline drawing of one embodiment of the present of invention

Fig. 3 is the gear wheel and the bit leg outline drawing of one embodiment of the present of invention

Fig. 4 is the drill bit of one embodiment of the present of invention and the shaft bottom outline drawing of formation

Fig. 5 is the gear wheel outline drawing of one embodiment of the present of invention

Fig. 6 is the gear wheel outline drawing of one embodiment of the present of invention

The specific embodiment

Below in conjunction with Fig. 2, Fig. 3 and Fig. 4 embodiments of the invention 1 are described:

This single-cone rotary drill bit mainly is made up of bit leg 1 and gear wheel 2, and drill bit rotates around axis of rotation 4.The gear wheel cloth flank of tooth is a surface of revolution that is made of a plurality of conical surfaces, and its gyroaxis overlaps with roller axle bearing axis 3, and the bus ABCDEF of the surface of revolution is connected and composed by a plurality of line segments.Its middle conductor AB wraparound rotating shaft 3 rotations generate the first secondary conical surface 5, and cone angle is θ (θ is the angle of AB and roller axle bearing axis 3); BC generates the first main cone face 6 perpendicular to drill bit axis of rotation 4 and wraparound rotating shaft 3 rotations; CD wraparound rotating shaft 3 rotations generate the second secondary conical surface 7, and cone angle is α (α is the angle of CD and roller axle bearing axis 3); And θ=180 °-2 β+α (β is the drill bit shaft inclination angle); DE wraparound rotating shaft 3 rotations generate the second main cone face 8, and cone angle is Φ (Φ is the angle of DE and roller axle bearing axis 3); EF wraparound rotating shaft 3 rotations generate the 3rd secondary conical surface 9.After gear wheel was assemblied on the bit body, bus ABCD was with respect to drill bit axis of rotation 4 symmetries, and the angle of AB and axis of rotation 4 equals the angle of CD and axis of rotation 4.

After installing tooth on the gear wheel, gear wheel cloth flank of tooth bus ABCDEF extension one tooth goes out the sword height and promptly forms the shaft bottom profile around the rotation of drill bit axis of rotation, as shown in Figure 4.The central area, shaft bottom that the broken rock of tooth on the first secondary conical surface, the first main cone face, the second secondary conical surface forms is darker than the exterior zone, makes the front end of drill bit gear wheel when rock is broken in motion imbed the central area all the time, forms a neck eye, stops drill bit to the slippage of well center.

Below in conjunction with Fig. 5 embodiments of the invention 2 are described:

This single-cone rotary drill bit mainly is made up of bit leg 1 and gear wheel 2, and drill bit rotates around axis of rotation 4.The gear wheel cloth flank of tooth is the surface of revolution that is made of a curved surface and a plurality of conical surface, and its gyroaxis overlaps with roller axle bearing axis 3, and the bus ABCDEF of the surface of revolution is connected and composed by a plurality of line segments.Its middle conductor AB wraparound rotating shaft 3 rotations generate the first secondary conical surface 5, and cone angle is θ (θ is the angle of AB and roller axle bearing axis 3); Curve B C wraparound rotating shaft 3 rotations generate curved surface 6; CD wraparound rotating shaft 3 rotations generate the second secondary conical surface 7, and cone angle is α (α is the angle of CD and roller axle bearing axis 3); DE wraparound rotating shaft 3 rotations generate main cone face 8, and cone angle is Φ (Φ is the angle of DE and roller axle bearing axis 3); EF wraparound rotating shaft 3 rotations generate the 3rd secondary conical surface 9.After gear wheel is assemblied on the bit body; Curve B C is with respect to drill bit axis of rotation 4 symmetries, and bus section, busbar section ABCD is with respect to drill bit axis of rotation 4 symmetries, and the angle of AB and axis of rotation 4 equals the angle of CD and axis of rotation 4.

After installing tooth on the gear wheel, it is high and around drill bit axis of rotation rotation promptly formation shaft bottom profile that gear wheel cloth flank of tooth bus ABCDEF extension one tooth goes out sword.The central area, shaft bottom that the broken rock of tooth on the first secondary conical surface, curved surface, the second secondary conical surface forms is darker than the exterior zone, makes the front end of drill bit gear wheel when rock is broken in motion imbed the central area all the time, forms a neck eye, stops drill bit to the well off-centring.

Below in conjunction with Fig. 6 the embodiment of the invention 3 is described:

This single-cone rotary drill bit mainly is made up of bit body 1 and gear wheel 2, and drill bit rotates around axis of rotation 4.The gear wheel cloth flank of tooth is that gyroaxis overlaps with roller axle bearing axis 3 by a curved surface and two surfaces of revolution that the conical surface constitutes.ABCD is the bus of the surface of revolution.Wherein AB is one section circular curve (or oval camber line, parabola, other type curve), after gear wheel is assemblied on the bit body, the center of circle P of circular curve AB overlaps (or the oval camber line center of circle, parabola axis of symmetry overlap with drill bit rotation 4) with drill bit rotation 4, curve A B is with respect to drill bit axis of rotation 4 symmetries.Curve A B wraparound rotating shaft 3 rotations generate curved surface 6; BC wraparound rotating shaft 3 rotations generate main cone face 8, and cone angle is Φ (Φ is the angle of BC and roller axle bearing axis 3); CD wraparound rotating shaft 3 rotations generate the secondary conical surface 9.After installing tooth on the gear wheel, it is high and around drill bit axis of rotation rotation promptly formation shaft bottom profile that gear wheel cloth flank of tooth bus ABCD extension one tooth goes out sword.The central area, shaft bottom that the broken rock of tooth on the curved surface 6 forms is darker than the exterior zone, shaft bottom that main cone face 8 teeth form, and the front end of gear wheel is imbedded the central area all the time when making drill bit movement, stops drill bit to the well off-centring.

Claims

1. single-cone rotary drill bit, mainly form by bit body and a gear wheel, the gear wheel cloth flank of tooth is the single-revolution curved surface, gyroaxis overlaps with the roller axle bearing axis, be installed with the tooth of energy fractured rock on the gear wheel cloth flank of tooth, it is characterized in that the gear wheel cloth flank of tooth is combined by two main cone faces and three secondary conical surfaces, after gear wheel is assemblied on the bit body, the revolution bus ABCD of the first secondary conical surface, the first main cone face and the second secondary conical surface is with respect to drill bit rotation symmetry, and first main cone face revolution bus BC is perpendicular to the drill bit axis of rotation.

2. single-cone rotary drill bit, mainly form by bit body and a gear wheel, the gear wheel cloth flank of tooth is the single-revolution curved surface, gyroaxis overlaps with the roller axle bearing axis, be installed with the tooth of energy fractured rock on the gear wheel cloth flank of tooth, it is characterized in that the gear wheel cloth flank of tooth is combined by a curved surface, a main cone face and two secondary conical surfaces, after gear wheel is assemblied on the bit body, the revolution bus ABCD of the first secondary conical surface, curved surface and the second secondary conical surface is with respect to drill bit rotation symmetry, and surface rotation bus BC is with respect to drill bit rotation symmetry.