阅读说明：本技术 自动换刃的pdc切削齿 (PDC cutting tooth with automatic blade changing function ) 是由 黄勇 朱丽红 邹德永 刘笑傲 潘龙 于 2020-07-29 设计创作，主要内容包括：本发明公开了一种自动换刃的PDC切削齿,包括滑动连接的上刃和下刃,上刃设置有上刃凹槽,下刃设置有下刃凹槽,上刃凹槽与下刃凹槽位置对应并且对扣形成容置腔；容置腔设有楔块组件,楔块组件与上刃凹槽的槽底之间留有滑动空间,楔块组件包括接触面为斜面的前楔块和后楔块,螺纹紧固件贯穿下刃且其螺杆段与前楔块螺纹连接；发明的自动换刃的PDC切削齿具有上刃和下刃两个切削刃,在下刃磨损后能自动更换新的切削刃即上刃进行切削,大幅延长了PDC切削齿的单齿使用寿命,延长了整个PDC钻头井下工作时间,减少了起下钻、更换钻头等钻井辅助时间,有效提高了钻井施工效率,降低了钻井成本。(The invention discloses a PDC cutting tooth capable of automatically changing blades, which comprises an upper blade and a lower blade which are connected in a sliding manner, wherein the upper blade is provided with an upper blade groove, the lower blade is provided with a lower blade groove, and the upper blade groove corresponds to the lower blade groove in position and is buckled with the lower blade groove to form an accommodating cavity; the containing cavity is provided with a wedge block assembly, a sliding space is reserved between the wedge block assembly and the bottom of the groove of the upper edge, the wedge block assembly comprises a front wedge block and a rear wedge block, the contact surfaces of the front wedge block and the rear wedge block are inclined planes, a threaded fastener penetrates through the lower edge, and a screw section of the threaded fastener is in threaded connection with the front wedge block; the PDC cutting tooth with the automatic blade changing function is provided with the upper blade and the lower blade, and the cutting blade which is a new cutting blade can be automatically changed after the lower blade is worn, namely the upper blade is used for cutting, so that the service life of a single tooth of the PDC cutting tooth is greatly prolonged, the underground working time of the whole PDC drill bit is prolonged, the drilling auxiliary time of tripping up and down, changing the drill bit and the like is reduced, the drilling construction efficiency is effectively improved, and the drilling cost is reduced.)

1. PDC cutting tooth of automatic change sword, its characterized in that includes:

the upper blade is connected with the lower blade in a sliding mode, an upper blade groove is formed in the upper blade, a lower blade groove corresponding to the upper blade groove is formed in the lower blade, and the lower blade groove and the upper blade groove are buckled to form an accommodating cavity;

the wedge block assembly is arranged in the accommodating cavity, a sliding space is reserved between the wedge block assembly and the bottom of the upper edge groove, the wedge block assembly comprises a front wedge block and a rear wedge block which are in contact with each other, and the contact surface of the front wedge block and the rear wedge block is an inclined surface;

and the threaded fastener penetrates through the lower blade, and a screw section of the threaded fastener is in threaded connection with the front wedge.

2. The automatic resharpening PDC cutter of claim 1 wherein the lower blade is provided with a lower blade stepped through bore in communication with the lower blade pocket, the lower blade stepped through bore including a large diameter bore in which the head of the threaded fastener is located and a small diameter bore in which the polished shaft section of the threaded fastener is located.

3. The automatically re-entrant PDC cutter of claim 1 wherein said ramp is inclined from bottom to top and from front to back and wherein the angle α between said ramp and the bottom plane of said wedge assembly is acute.

4. The automatic resharpened PDC cutter of claim 3 wherein α is 45 ° -65 °.

5. The automatically re-bladed PDC cutter of claim 1 wherein the upper blade flutes have a flute depth greater than the flute depth of the lower blade flutes.

6. The PDC cutter of claim 1 wherein the upper blade and the lower blade are each formed by a cemented carbide substrate and a polycrystalline diamond layer, the upper blade groove being formed in the cemented carbide substrate of the upper blade, and the lower blade groove being formed in the cemented carbide substrate of the lower blade.

7. The automatically re-bladed PDC cutter of claim 6 wherein the thickness of the cemented carbide substrate of the upper blade is greater than the thickness of the cemented carbide substrate of the lower blade.

8. The automatic resharpening PDC cutter of claim 6 wherein the cutting face of the polycrystalline diamond layer is planar; or the edge surface of the polycrystalline diamond layer is a special-shaped surface.

9. The PDC cutter of claim 1 wherein the upper blade and the lower blade are slidably coupled together by a sliding engagement structure, the sliding engagement structure comprising a dovetail projection disposed on the upper blade and a dovetail groove disposed on the lower blade, the dovetail projection being slidably engaged with the dovetail groove, the upper blade groove being formed in the dovetail projection, and the lower blade groove being formed in the dovetail groove.

10. The PDC cutting tooth with an automatically replaced blade according to claim 9, wherein the upper blade and the lower blade are connected to form a cylindrical surface, the dovetail protrusion is an arc-shaped dovetail protrusion, the dovetail groove is an arc-shaped dovetail groove, the center of the arc-shaped dovetail protrusion is offset from the center of the cylindrical surface, and the arc radius of the arc-shaped dovetail protrusion is smaller than or equal to the arc radius of the cylindrical surface.

Technical Field

The invention relates to the technical field of tools for petroleum and natural gas exploration equipment, in particular to a PDC cutting tooth with an automatic blade changing function.

Background

With the decreasing of conventional oil and gas resources, deep and complex formation oil and gas reservoirs become the key points of oil and gas exploration and development. The PDC drill bit as a preferred rock breaking tool has an unsatisfactory drilling effect on deep and complex strata, and mainly shows that the drilling speed is slow and the service life of the drill bit is short. The main reason for the poor application effect of the PDC drill bit in the stratum is that the PDC cutting teeth serving as a direct rock breaking tool are worn quickly in the stratum with poor drillability and high abrasiveness, once the PDC cutting teeth are worn, the rock breaking capacity of the PDC cutting teeth is greatly reduced, and the drilling efficiency is remarkably reduced.

In recent years, the technology of PDC cutting teeth has been rapidly developed, and in order to improve the adaptability to hard and complex strata, non-planar special-shaped PDC cutting teeth such as conical teeth, axe-shaped teeth, multi-edge teeth and the like have appeared. The special-shaped PDC cutting teeth provide a new rock breaking idea for oil and gas drilling, but the problems that single teeth are easy to wear and short in service life still exist. Practice shows that the service life of the PDC drill bit is determined by the service life of the PDC cutting teeth on the PDC drill bit, and the key for prolonging the underground working time of the drill bit and ensuring the drilling efficiency is to improve the service life of a single tooth. In conclusion, how to greatly prolong the service life of a single PDC cutting tooth is still a technical problem to be solved urgently in the field of petroleum drilling.

Disclosure of Invention

In view of the above, the technical problems to be solved by the present invention are: the utility model provides an automatic trade PDC cutting tooth of sword, can be after the PDC cutting tooth wearing and tearing certain degree, the automatic cutting edge of renewing, sharpness that improves PDC monodentate life effectively guarantees PDC drill bit drilling efficiency and operating time in the pit.

In order to solve the technical problems, the technical scheme of the invention is as follows: a PDC cutter with automatic blade changing comprising:

the upper blade is connected with the lower blade in a sliding mode, an upper blade groove is formed in the upper blade, a lower blade groove corresponding to the upper blade groove is formed in the lower blade, and the lower blade groove and the upper blade groove are buckled to form an accommodating cavity;

the wedge block assembly is arranged in the accommodating cavity, a sliding space is reserved between the wedge block assembly and the bottom of the upper edge groove, the wedge block assembly comprises a front wedge block and a rear wedge block which are in contact with each other, and the contact surface of the front wedge block and the rear wedge block is an inclined surface;

and the threaded fastener penetrates through the lower blade, and a screw section of the threaded fastener is in threaded connection with the front wedge.

The lower blade is provided with a lower blade stepped through hole communicated with the lower blade groove, the lower blade stepped through hole comprises a large-diameter hole and a small-diameter hole, the head of the threaded fastener is located in the large-diameter hole, and the polished rod section of the threaded fastener is located in the small-diameter hole.

The inclined plane inclines from bottom to top and from front to back, and an included angle alpha between the inclined plane and the bottom plane of the wedge block assembly is an acute angle.

Wherein, furthermore, the alpha is 45-65 degrees.

Wherein the groove depth of the upper blade groove is greater than the groove depth of the lower blade groove.

The upper blade and the lower blade are both formed by compounding a hard alloy matrix and a polycrystalline diamond layer, the upper blade groove is formed in the hard alloy matrix of the upper blade, and the lower blade groove is formed in the hard alloy matrix of the lower blade.

Wherein the cemented carbide substrate of the upper edge has a thickness greater than a thickness of the cemented carbide substrate of the lower edge.

Wherein the edge surface of the polycrystalline diamond layer is a plane; or the edge surface of the polycrystalline diamond layer is a special-shaped surface.

Wherein, go up the sword with the lower blade passes through sliding connection structure sliding connection, sliding connection structure including set up in go up the forked tail arch of sword with set up in the forked tail recess of lower blade, the forked tail arch with forked tail recess sliding fit, go up the sword recess and set up in the forked tail arch, the lower blade recess is set up in the forked tail recess.

The outer surfaces of the upper blade and the lower blade are connected to form a cylindrical surface, the dovetail protrusions are arc dovetail protrusions, the dovetail grooves are arc dovetail grooves, the circle center of each arc dovetail protrusion is offset from the circle center of the cylindrical surface, and the arc radius of each arc dovetail protrusion is smaller than or equal to that of the cylindrical surface.

After the technical scheme is adopted, the invention has the following beneficial effects:

the PDC cutting tooth with the automatic blade changing function comprises an upper blade and a lower blade which are connected in a sliding mode, wherein the upper blade is provided with an upper blade groove, the lower blade is provided with a lower blade groove, and the upper blade groove corresponds to the lower blade groove in position and is buckled with the lower blade groove to form an accommodating cavity; the containing cavity is provided with a wedge block assembly, a sliding space is reserved between the wedge block assembly and the bottom of the upper edge groove, and the wedge block assembly comprises a front wedge block and a rear wedge block, the contact surfaces of which are inclined planes; the screw rod section of the threaded fastener penetrates through the lower blade and is in threaded connection with the front wedge block; during the drilling process, the lower cutting edge of the PDC cutting tooth cuts broken rocks, meanwhile, the PDC cutting tooth is continuously worn by the rocks, the contact surface area of the lower cutting edge and the rocks is continuously increased, the rock breaking capacity is reduced, and the drilling speed is slowed down; when the lower blade is worn, the threaded fastener for fixing the lower blade is worn together, when the head of the threaded fastener is worn completely, the threaded fastener fails to fix the lower blade, the lower blade moves in the opposite direction of the cutting direction under the action of the cutting resistance of the PDC cutting teeth, the front wedge block slides upwards and backwards relative to the rear wedge block and slides into the sliding space of the accommodating cavity along the inclined plane, and the upper blade of the cutting teeth is exposed, so that automatic blade replacement is realized; and as the upper cutting edge is a new cutting edge which is not worn, the rock breaking capacity of the cutting teeth is recovered, and high-speed rock breaking is realized again.

The PDC cutting tooth with the automatic blade changing function is provided with the upper blade and the lower blade, and the cutting blade which is a new cutting blade can be automatically changed after the lower blade is worn, namely the upper blade is used for cutting, so that the service life of a single tooth of the PDC cutting tooth is greatly prolonged, the underground working time of the whole PDC drill bit is further prolonged, the drilling auxiliary time of tripping, changing the drill bit and the like is reduced, the drilling construction efficiency is effectively improved, and the drilling cost is reduced.

Drawings

FIG. 1 is a schematic diagram of an exploded PDC cutter with automatic blade changing according to a first embodiment of the present invention;

FIG. 2 is a front view of FIG. 1 assembled;

FIG. 3 is a top view of FIG. 2;

FIG. 4 is a schematic cross-sectional view A-A of FIG. 2;

FIG. 5 is a schematic view of the lower edge structure of FIG. 1;

FIG. 6 is a schematic view of the upper blade configuration of FIG. 1;

FIG. 7 is a schematic illustration of the rear wedge construction of FIG. 1;

FIG. 8 is a schematic view of the front wedge construction of FIG. 1;

FIG. 9 is a schematic illustration of the concave land of an automatically resharpened PDC cutter in accordance with a second embodiment of the present invention;

FIG. 10 is a schematic view of the convex land of a third embodiment of the present invention of an automatically resharpened PDC cutter;

FIG. 11 is a schematic bottom cutting view of a self-resharpening PDC cutter of the present invention;

FIG. 12 is a schematic view of the lower edge of FIG. 11 after wear;

FIG. 13 is a schematic view of the automatic top edge change cutting of FIG. 12 after wear of the bottom edge;

in the figure: 1-an upper blade; 11-dovetail lobes; 12-upper edge groove; 1 a-upper edge hard alloy matrix; 1 b-an upper edge polycrystalline diamond layer; 2-a lower edge; 21-dovetail grooves; 22-lower edge groove; 23-lower blade step through hole; 2 a-lower blade cemented carbide substrate; 2 b-a lower edge polycrystalline diamond layer; 3-front wedge block; 31-a threaded hole; 4-rear wedge block; 5-a threaded fastener; b-sliding space.

Detailed Description

The invention is further illustrated in the following non-restrictive description with reference to the figures and examples.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "front", "rear", "bottom", and the like, indicate orientations or positional relationships based on those shown in the drawings, are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention.