CN105201414A - Drill bit used for volcanic rock - Google Patents

Abstract

The invention relates to a drill bit used for volcanic rock. The drill bit used for volcanic rock comprises a casing and a drill bit body, wherein the casing is provided with multiple cutter wings, and the cutter wings extend from the head of the casing to the tail of the casing along the outer side of the casing; the casing is arranged at the head of the drill bit body, and the head of the drill bit body can be connected to a drill stem; the crown portion of each cutter wing comprises an embedded cutting block which is of a layered structure, and when the drill bit conducts rotary drilling, the embedded cutting blocks abrase and cut the rock. When the drill bit used for the volcanic rock is adopted for conducting drilling, the abrasive property is good, and the drilling speed is high.

Description

drill bit for volcanic rock

technical field

The invention relates to the technical field of rock breaking in deep well volcanic formations, in particular to a drill bit for volcanic rocks.

Background technique

Deep formations in deep and ultra-deep wells in domestic oilfields generally have the characteristics of high abrasiveness, high hardness, poor drillability and instability of wellbore walls, resulting in low drilling speed and long drilling cycle of drilling machinery in such formations. PDC (PolycrystallineDiamondCompact) bit and impregnated diamond bit are two different self-sharpening bits. The former is mainly used for cutting and breaking rocks; the latter is used for micro-shearing and grinding to break rocks. Cooperate use, but with regard to prior art, above-mentioned two kinds of drill bits are prone to the problems that it is difficult to eat into the formation and the ROP is low when drilling into highly abrasive formations such as volcanic rocks. The Permian volcanic rocks are developed in the Maigaiti area of the Tarim Basin, the formations are highly abrasive, the drillability is poor, and the well wall is prone to instability and collapse. Therefore, a drill bit for volcanic rocks with good abrasive resistance, fast drilling speed, and high safety performance is urgently needed .

Contents of the invention

In view of the above problems, the present invention proposes a drill bit for volcanic rock, which has good abrasiveness and fast drilling speed when used for drilling, thereby shortening the drilling cycle.

The invention proposes a drill bit for volcanic rocks, comprising: a matrix, which is provided with a plurality of blades, and the blades extend from the head of the matrix to the tail of the matrix along the outer side of the matrix; the bit body, the matrix is fixed on The head of the bit body, and the tail of the bit body can be connected to the drill pipe; wherein the crown of the blade includes impregnated cutting blocks configured in layers, which grind the rock as the bit rotates to drill.

It can be seen that, since the blade of the drill bit for volcanic rock is provided with an impregnated cutting block capable of cutting rock, when the drill bit enters the bottom of the well and begins to drill, the layered impregnated cutting block first grinds and breaks the rock, In addition, the impregnated cutting block increases the working thickness of the drill bit, and the working area when the drill bit contacts the bottom of the well is reduced, which effectively improves the rock-breaking efficiency of the drill bit and the drilling speed of the drill bit, thus shortening the drilling cycle.

In one embodiment, the impregnated cutting block includes a surface-set working layer disposed on its surface, and the surface-set working layer is provided with natural diamond. This increases the wear resistance of the blade crown and the penetration rate.

In one embodiment, the impregnated cutting block further includes an impregnated working layer, the impregnated working layer is arranged inside the surface-embedded working layer, and a synthetic diamond single crystal is arranged in the impregnated working layer. During the drilling process of the drill bit, when the natural diamond in the surface-embedded working layer is consumed, the impregnated working layer of the blade is used to continue working, thereby increasing the service life of the drill bit.

In one embodiment, the particle size of the natural diamond is 8-10 grains/carat, and the particle size of the synthetic diamond single crystal is 20-40 mesh. The particle size of natural diamond and synthetic diamond single crystal adopts the above particle size to effectively grind rock while saving cost.

In one embodiment, the composition of the matrix includes rare earth elements. Rare earth elements are added to the carcass, so that the bending strength of the drill bit is increased by 30%-50%, and the hardness is increased by 10%-15%.

In one embodiment, the impregnated cutting block has a working thickness of 20-30 mm. As a result, the lifetime of the drill bit is increased with regard to costs.

In one embodiment, the blade further includes a gauge portion, the gauge portion extends from the crown of the blade along the outside of the carcass, wherein the length of the gauge portion along the axis of the drill bit is not less than 90 mm, because the gauge portion It has the function of reaming and back reaming. The diameter gauge part of the blade adopts the above size to make the diameter protection effect of the blade better and improve the drilling effect.

In one embodiment, the head of the carcass is provided with 6-10 water holes, and the diameter of the water holes is 6-15 mm. The cut rock is thereby flushed in time and the continuously working drill bit is cooled down in time.

In one embodiment, three rows of teeth are arranged non-interferingly and eccentrically at the center of the carcass head, wherein one row of the three rows of teeth includes 3 PDC composite sheets, and the other two rows of the three rows of teeth include 2 PDC composite sheets. piece. Since the PDC composite sheet has the characteristics of high wear resistance and good impact toughness, three rows of teeth are arranged eccentrically in the center of the carcass head in a non-interfering manner, which avoids the low speed and slow line speed at the center of the carcass head. Resulting in a problem of pre-wear at the center.

In one embodiment, the diameter of the PDC composite sheet is 9-15mm. This facilitates the cutting of rock.

In one embodiment, the diameter of the cutting circle centered on the center point of the carcass head where the three rows of teeth are located is 30-100mm. Thereby improving the drilling efficiency of the drill bit.

In one embodiment, the carcass is provided with 6 blade groups, and each blade group includes 2 blades arranged at intervals, and any one of the 2 blades extends radially from the cutting arc to the top of the carcass head. The peripheral edge, and a runner groove is arranged between two adjacent blade groups, and the runner groove extends radially from the cutting circle to the peripheral edge of the carcass head. Since the runner grooves are radial, the area of the runner grooves is increased, which is beneficial to the timely cooling and chip removal of the drill bit, and at the same time, the rock blocks are held in the runner grooves. There are 6 blade groups, and each blade group includes 2 blades, so that the drilling and cutting performance of the drill bit is better.

Compared with the prior art, the present invention has the advantages that the setting of the impregnated cutting block on the blade crown reduces the working area when the drill bit contacts the bottom of the well, increases the strength of the matrix and the impregnated cutting block, and can withstand higher The large drilling pressure and torque enable the drill bit to be used in conjunction with medium and high-speed screw rods, thereby improving the versatility of the drill bit, reducing the cost of drilling work, improving the drilling speed of the bit, the footage of a single bit and the drilling efficiency, and shortening the drilling time. Drilling cycle, improve the progress of exploration and development of oil and gas fields.

Description of drawings

Hereinafter, the present invention will be described in more detail based on the embodiments with reference to the accompanying drawings. in:

Fig. 1 is the plan view of drill bit for volcanic rock according to the present invention;

Fig. 2 is a sectional view of a drill bit for volcanic rock according to the present invention.

In the figures, the same components are designated by the same reference numerals. The drawings are not drawn to scale.

Detailed ways

The present invention will be further described below in conjunction with accompanying drawing.

The drill bit for volcanic rock provided by the present invention includes a matrix and a drill body, the matrix is arranged on the head of the drill body, and the drill body is used to connect the drill bit to a drill rod. The drill bit of the present invention and parts thereof will be described in detail below.

As shown in Figures 1 and 2, the carcass 3 is provided with a plurality of blades 4, and the blades 4 extend from the head of the carcass 3 to the tail of the carcass 3 along the outside of the carcass 3; The head of the body 7 and the tail of the drill body 7 can be connected to the drill rod, so that the drill rod can drive the drill to rotate; wherein the crown 40 of the blade 4 includes a layered impregnated cutting block 401, when the drill rotates When drilling, the impregnated cutting block 401 grinds the rock.

In a preferred embodiment, the impregnated cutting block 401 includes a surface-set working layer disposed on its surface, and the surface-set working layer is provided with natural diamond. This increases the wear resistance of the crown 40 of the blade 4 and the penetration rate.

Further, the impregnated cutting block 401 also includes an impregnated working layer, the impregnated working layer is arranged inside the surface-embedded working layer, and a synthetic diamond single crystal is arranged in the impregnated working layer. During the drilling process of the drill bit, after the natural diamond in the surface-embedded working layer is consumed, the impregnated working layer of the blade 4 is used to continue working, thereby improving the service life of the drill bit.

Preferably, the particle size of the natural diamond is 8-10 grains/carat, and the particle size of the synthetic diamond single crystal is 20-40 mesh. The particle size of natural diamond and synthetic diamond single crystal adopts the above-mentioned particle size, which can effectively grind rocks while saving cost.

In a preferred embodiment, the composition of the carcass 3 includes rare earth elements. Rare earth elements such as lanthanum or cerium are added to the matrix 3, so that the bending strength of the drill bit is increased by 30%-50%, and the hardness is increased by 10%-15%.

Preferably, the working thickness of the impregnated cutting block 401 is 20-30mm. This increases the service life of the blade.

Further, the blade 4 further includes a gauge portion 41 extending from the crown 40 of the blade 4 along the outside of the carcass 3 , wherein the length of the gauge portion 41 along the axis of the drill bit is not less than 90 mm. Since the gauge part 41 has the functions of reaming and back reaming, the longer the gauge part 41 has the better the gauge function and the better the drilling effect under the condition of ensuring smooth drilling.

Preferably, the head of the carcass 3 is provided with 6-10 water holes 2, and the diameter of the water holes 2 is 6-15mm. The cut rock is thereby flushed in time and the continuously working drill bit is cooled down in time.

In addition, as shown in Figure 1, three rows of teeth are non-interferingly arranged eccentrically at the center of the head of the carcass 3, wherein one row of the three rows of teeth includes three PDC composite sheets 1, and the other two rows of the three rows of teeth include 2 PDC composite sheets 1. Specifically, one of the other two rows is arranged near the inner side of the carcass 2 head, and the other of the other two rows is arranged near the outer side of the carcass 2 head. In the cutting circle 8 (see Fig. 1 ) with the center point of the head of the carcass 3 where the three rows of teeth are located, the PDC composite sheets 1 between the rows are staggered to make the three rows of teeth cut out as much as possible. A complete cutting circle 8, that is, three rows of teeth, when the drill bit rotates and drills, after the 3 PDC composite sheets are cut in one row, the PDC composite sheets on the other two rows cut off the rock that it missed. The cutting speed of the PDC composite sheet 1 is improved through this way of tooth arrangement, and the drilling efficiency of the drill bit is improved.

Further, the diameter of the PDC composite sheet 1 is 9-15mm. Tests have proved that the PDC composite sheet 1 can cut rocks well by adopting the above-mentioned dimensions. In a preferred embodiment, the diameter of the cutting circle 8 with the center point of the head of the carcass 3 as the center where the three rows of teeth are located is 30-100 mm.

As a preferred embodiment, as shown in Figure 1, the carcass 3 is provided with 6 blade groups, each blade group includes 2 blades arranged at intervals, and any one of the 2 blades is radial from the cutting circle 8 Extending to the periphery of the head of the carcass 3, and between two adjacent groups of blades 4, flow channel grooves 6 are arranged, and the flow channel grooves 6 extend radially from the cutting circle 8 to the periphery of the head of the carcass 3. Since the runner groove 6 is radial, increasing the area of the runner groove 6 is beneficial to the timely cooling and chip removal of the drill bit, and the radially extending diversion groove 6 prevents rock blocks from being stuck in the runner groove 6 . Six blade groups are provided, and each blade group includes two blades 4, so that the drilling and cutting performance of the drill bit is better.

While the invention has been described with reference to a preferred embodiment, various modifications may be made and equivalents may be substituted for parts thereof without departing from the scope of the invention. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims (12)

1. A drill bit for volcanic rock, characterized in that it comprises: a carcass, which is provided with a plurality of blades, and the blades extend from the head of the carcass along the outer side of the carcass to the tail of the carcass; a drill body, the matrix is fixed to the head of the drill body, and the tail of the drill body can be connected to a drill rod; Wherein the crown of the blade includes an impregnated cutting block configured in layers, and when the drill bit rotates and drills, the impregnated cutting block grinds rock. 2 . The drill bit for volcanic rock according to claim 1 , wherein the impregnated cutting block includes a surface-embedded working layer arranged on its surface, and the surface-embedded working layer is provided with natural diamond. 3 . 3. The drill bit for volcanic rock according to claim 2, wherein the impregnated cutting block further comprises an impregnated working layer, the impregnated working layer is arranged inside the surface-embedded working layer, and the impregnated working layer An artificial diamond single crystal is arranged in the inlaid working layer. 4. The drill bit for volcanic rock according to claim 3, characterized in that, the particle size of the natural diamond is 8-10 grains/carat, and the particle size of the synthetic diamond single crystal is 20-40 mesh. 5. The drill bit for volcanic rock according to any one of claims 1 to 4, characterized in that the components of the matrix include rare earth elements. 6. The drill bit for volcanic rock according to claim 3, characterized in that, the working thickness of the impregnated cutting block is 20-30mm. 7. The drill bit for volcanic rock according to claim 6, wherein the blade further comprises a gage part, and the gage part extends from the crown of the blade along the outer side of the matrix, wherein The length of the gage part along the axial direction of the drill bit is not less than 90 mm. 8. The drill bit for volcanic rock according to claim 3, characterized in that 6-10 water holes are arranged on the head of the matrix, and the diameter of the water holes is 6-15 mm. 9. The drill bit for volcanic rock according to claim 8, characterized in that three rows of teeth are non-interferentially arranged eccentrically at the center of the carcass head, wherein one row of the three rows of teeth includes three PDC composite sheets, and the other two rows of the three rows of teeth include two PDC composite sheets. 10. The drill bit for volcanic rock according to claim 9, characterized in that the diameter of the PDC composite sheet is 9-15 mm. 11 . The drill bit for volcanic rock according to claim 9 , wherein the diameter of the cutting circle centered on the center point of the carcass head where the three rows of teeth are located is 30-100 mm. 12. The drill bit for volcanic rock according to claim 11, wherein the matrix is provided with 6 blade groups, each blade group includes 2 blades arranged at intervals, and among the 2 blades Any one of them extends radially from the cutting arc to the periphery of the carcass head, and a flow channel groove is arranged between two adjacent blade groups, and the flow channel groove extends radially from the cutting circle radially extending to the periphery of the carcass head.