CN218150764U

CN218150764U - Hole-scratching tool for soft and easily collapsed well section

Info

Publication number: CN218150764U
Application number: CN202220895113.2U
Authority: CN
Inventors: 陈小元; 刘纯仁; 王委; 李志兵; 程智勇; 秦春
Original assignee: Sinopec Oilfield Service Corp; Sinopec East China Petroleum Engineering Corp
Current assignee: Sinopec Oilfield Service Corp; Sinopec East China Petroleum Engineering Corp
Priority date: 2022-04-18
Filing date: 2022-04-18
Publication date: 2022-12-27
Anticipated expiration: 2032-04-18

Abstract

The utility model relates to a reaming instrument of soft well section that easily collapses, including the PDC drill bit body, the upper portion of PDC drill bit body is equipped with PDC drill bit screw thread, the lower part of PDC drill bit body is equipped with the coronal bottom, evenly be equipped with a plurality of blades on the coronal bottom, it has blade cutting teeth to distribute on the blade, the center of coronal bottom is equipped with downwardly extending cylindric guide post, the bottom of cylindric guide post is equipped with the arc guide head, evenly be equipped with the guide post cutting teeth of multirow along vertical extension on the circumference of cylindric guide post, evenly distribute on the upper portion circumference of cylindric guide post and guide post slant nozzle down; three guide column blades are symmetrically arranged at the middle section of the cylindrical guide column, and blade cutting teeth are respectively arranged on two side walls of each guide column blade. The lower parts of the chip grooves between the blades are provided with axial nozzles of the bit body, and the middle upper parts of the chip grooves are provided with nozzles of the bit body which inclines upwards. The tool has high reaming speed, can effectively prevent new well holes and drill bit mud bags from being reamed, and can be directly used for finding old well holes.

Description

Hole-scratching tool for soft and easily collapsed well section

Technical Field

The utility model relates to a reaming instrument is used in well drilling, in particular to reaming instrument of soft well section that easily collapses belongs to well drilling instrument technical field.

Background

In oil field drilling, complex strata such as sandstone well sections, plastic mudstone well sections, sand-mudstone interbeddes and the like with high permeability are frequently encountered. In the sandstone well section with strong permeability, the well wall is easy to form a virtual thick mud cake, in addition, the clay content in the plastic mudstone well section is high, the water sensitivity is strong, the hole shrinkage and the collapse dropping block are easy to creep when meeting water, and particularly, the stratum stability in the sand mudstone interbedding is poor, and the hole shrinkage, the corrosion, the block dropping and the collapse are easy to occur. Once this phenomenon occurs, the light person causes the pump to be difficult to open, press the pump, pull the piston out, get down and meet the resistance, and the instrument meets the resistance during the electric measurement. In severe cases, the well needs to be reamed. Aiming at the above situation, in order to eliminate the well wall resistance point, the well needs to be opened, a roller bit, a PDC bit or even a pilot cone or a single-bend power drilling tool is used for reaming, the well wall is trimmed, the smoothness of the well wall is ensured, and then the next operation is carried out.

When a PDC bit or a roller cone bit is used to open a well and cut a hole, a bit nozzle is usually designed to be downward-jetting because a conventional bit nozzle is designed based on drilling and sand-carrying. In the drilling process, because the drill bit contacts the well bottom, the overflow effect of water jet is generated, which is beneficial to the timely return of rock debris. However, in the reaming process, because the drill bit nozzle is designed to spray downwards, for the diameter-reducing well section, most of the spray jet flows to the lower open well shaft, when the spray jet flows back to the wall of the diameter-reducing well, the upward return speed of the water jet is obviously reduced, and the scouring force on the wall of the diameter-reducing well is insufficient. In addition, the downhole is complicated when the hole is scratched, the phenomena of diameter shrinkage, collapse and the like exist, in order to prevent the pump-out phenomenon from occurring, the downhole complicated deterioration is caused, the discharge capacity of the hole scratching is generally lower than the discharge capacity during drilling, the upward return speed of rock debris is further insufficient, the residence time of the rock debris in the well is long, the drill bit cannot be effectively cleaned, and the drill bit mud pocket is further caused. If meet big section soft mud rock, cause the drill bit mud package more easily, influence the availability factor, cause the reaming progress slow, do not have the footage even. In addition, in the stratum with the staggered hardness and softness, different well diameters and better stratum drillability, a new hole is easy to be marked out during the hole marking, the footage of the lower well section is scrapped, and even the well is filled and sidetracked, so that huge economic loss is caused.

When the pilot cone is used for reaming, the front part of the pilot cone is a conical guide head, and the upper part of the pilot cone consists of 3 scraper wings. The guide head is arranged, so that the pilot cone can be always positioned in an old well hole, and the scraper blade has no cutting function, so that a new well hole can be effectively prevented from being marked; however, the pilot head and the scraper wing of the pilot cone are not designed with cutting rock breaking teeth, and the reaming speed is very slow. The male cone is easily damaged when encountering a hard stratum in a sand-shale interface, so that a complex fault is caused; and secondly, the pilot hole male cone only has one water hole at the position of the guide head, no water hole exists at the position of the scraper wing, the impact force of the upward returning drilling fluid on the water jet of the scraper wing is small, and mud pockets are still easy to occur when plastic stratum with easy diameter reduction is scratched. In addition, due to the limitation of a material structure, rock breaking cutting teeth such as PDC composite sheets are not embedded on the male cone, the scraping and breaking capacities on the well wall with the reduced diameter and collapsed objects are poor, the reaming effect is poor, new holes are accidentally formed, once the new holes are formed, the mechanical drilling speed is low due to the poor rock breaking capacity, and the rock breaking cutting teeth cannot be directly used for finding old well holes. Because the guide head of the pilot hole male cone is long, about 0.8m long and low in strength, when a hole is scratched in a collapsed stratum, the drill tool is easy to break due to serious bouncing and high torque.

In the field, in order to pursue a faster drifting and reaming speed sometimes, and in order to save one drilling, a drilling tool combination of a conventional tower type drilling tool and a pendulum drilling tool is not used for reaming, a drilling tool combination of a PDC drilling bit, a single-bent screw rod and a wireless drilling inclinometer is put in for reaming, the drilling tool combination is drilled into a well section with large full-angle change rate, such as a deflecting section, a loose stratum, a sandstone interface, a big belly, a reducing well section and other well diameter irregular well sections, during reaming, due to the influence of factors such as pendulum force, the drilling bit is easy to contact with a shoulder at the large and small well hole junctions, due to the fact that the stratum is soft and the bit pressure is small, but the drilling speed of a drilling machine is high, the reaming is considered to be easy on the field, a new hole is not found in time, and the new hole is continuously drilled, so that the new hole is formed at the lower wall of the well hole, when the extracted sand is rock debris of the new stratum, or the inclination and the azimuth of an analysis well are different from the old well, the new hole is discovered, and the new hole is drilled for a long distance. Especially when using power drill to cut the hole, because screw rod and drill bit rotational speed are high, it is higher to advance the mechanical drilling speed in new borehole, is changeed out new hole.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to overcome the easy mud drum that exists among the prior art, easily go out the problem of new eye, provide a hole digging instrument of soft well section that easily collapses, the hole digging is fast, can effectively prevent to draw new well and drill bit mud drum, and can directly be used for looking for old well eye, can be used to when the loose and soft stratum that easy undergauge collapsed such as the sandstone that the permeability is strong, plasticity mudstone or sand mudstone interbedded draws the hole.

In order to solve the technical problem, the utility model discloses a soft reaming instrument of collapse prone well section, including the PDC drill bit body, the upper portion of PDC drill bit body is equipped with PDC drill bit screw thread, the lower part of PDC drill bit body is equipped with the coronal bottom, evenly be equipped with a plurality of blades on the coronal bottom, the distribution has blade cutting teeth on the blade, the center of coronal bottom is equipped with downwardly extending cylindric guide post, the bottom of cylindric guide post is equipped with the arc guide head, evenly be equipped with the guide post cutting teeth of multirow along vertical extension on the circumference of cylindric guide post, evenly distributed has guide post slant nozzle down on the upper portion circumference of cylindric guide post; the middle section of the cylindrical guide column is symmetrically provided with three guide column blades, and two side walls of each guide column blade are respectively provided with blade cutting teeth.

As the improvement of the utility model, be equipped with the drill bit body chip groove between the wing of coronal bottom respectively, the lower part of each drill bit body chip groove is equipped with drill bit body axial nozzle respectively, and the well upper portion of each drill bit body chip groove is equipped with the nozzle that the drill bit body goes up to one side respectively.

As a further improvement of the utility model, the bottom of the arc-shaped seeker is provided with a horizontal cutting surface, and the center of the horizontal cutting surface is provided with a seeker center nozzle.

As a further improvement of the utility model, the blades are evenly provided with three on the circumference of the crown-shaped bottom.

As a further improvement of the utility model, the included angle between the axis of the downward inclined nozzle of the guide post and the axis of the cylindrical guide post is 45 degrees.

As a further improvement of the utility model, the included angle between the axis of the nozzle on the inclined upper part of the drill bit body and the axis of the PDC drill bit body is 45 degrees.

As a further improvement of the present invention, the distance between the top of the guide post blade and the crown bottom is 0.15m.

As a further improvement of the present invention, the outer diameter of the guide post blade is 80% of the outer diameter of the blade, and the guide post oblique lower nozzle is located between the two adjacent guide post blades on the phase.

As a further improvement of the utility model, the thickness of the guide post blade is larger than 15mm, and the width is smaller than 200mm.

As a further improvement of the utility model, the guide post nozzle under slant, bit body axial nozzle and the nozzle on the bit body slant are pulse nozzle.

Compared with the prior art, the utility model discloses following beneficial effect has been obtained: the drilling tool integrates the high reaming speed of the conventional PDC drill bit and the guiding effect of the pilot cone, can be used in combination with a screw and MWD drilling tool, can be used for reaming a soft and easily collapsed long well section or finding an old well hole, can effectively avoid the scratching of a new well hole, can prevent the balling of the drill bit, has higher reaming speed, can effectively shorten the complex fault treatment period in a well, and saves the drilling cost.

Drawings

Fig. 1 is a structural diagram of the reaming tool for the well section which is soft and easy to collapse.

In the figure: 1, threading a PDC drill bit; a PDC bit body; 3. a blade; 3a, cutting teeth of the blade; 4. a chip groove of the drill bit body; 4a, a drill bit body axial nozzle; 4b, the drill bit body is obliquely upward to form a nozzle; 5. a cylindrical guide post; 5a, guiding column cutting teeth; 5b, leading the column to incline the lower nozzle; 6. a guide post blade; 6a, cutting teeth of the blade; 7. an arc seeker; 7a, guiding the center nozzle of the head.

Detailed Description

As shown in figure 1, the utility model discloses reaming instrument of soft easy collapse well section includes PDC drill bit body 2, and the upper portion of PDC drill bit body 2 is equipped with PDC drill bit screw thread 1 and links to each other with the drilling rod, and the lower part of PDC drill bit body 2 is equipped with the crown bottom, evenly is equipped with a plurality of wing 3 on the crown bottom, and it has wing cutting teeth 3a to distribute on the wing 3. The center of the crown-shaped bottom is provided with a cylindrical guide column 5 extending downwards, the bottom of the cylindrical guide column 5 is provided with an arc-shaped guide head 7, the bottom of the arc-shaped guide head 7 is provided with a horizontal cutting surface, and the center of the horizontal cutting surface is provided with a guide head center nozzle 7a.

A plurality of rows of guide post cutting teeth 5a extending vertically are uniformly arranged on the circumference of the cylindrical guide post 5, guide post inclined lower nozzles 5b are uniformly distributed on the circumference of the upper part of the cylindrical guide post 5, and an included angle between the axis of the guide post inclined lower nozzle 5b and the axis of the cylindrical guide post is 45 degrees and is a pulse nozzle.

Three guide column blades 6 are symmetrically arranged at the middle section of the cylindrical guide column 5, and blade cutting teeth 6a are respectively arranged on two side walls of each guide column blade 6.

Drill bit body chip grooves 4 are respectively arranged between the blades 3 at the crown bottom, the lower parts of the drill bit body chip grooves 4 are respectively provided with a drill bit body axial nozzle 4a, the middle upper parts of the drill bit body chip grooves 4 are respectively provided with a drill bit body obliquely upward nozzle 4b, the included angle between the axis of the drill bit body obliquely upward nozzle 4b and the axis of the PDC drill bit body 2 is 45 degrees, and the drill bit body axial nozzle 4a and the drill bit body obliquely upward nozzle 4b are pulse nozzles.

The conventional PDC drill bit is generally 4-7 blades, three blades 3 of the tool can be uniformly arranged on the circumference of the crown bottom, and the blades are less beneficial to preventing mud bags.

The distance between the top and the crown bottom of the guide post blade 6 is 0.15m, and the outer diameter of the guide post blade 6 is designed to be 80% of the outer diameter of the blade wing. The thickness of the guide post blade 6 is more than 15mm, and the width is less than 200mm.

This instrument processes a cylindric guide post 5 similar pilot hole public cone at the bottom center of PDC drill bit body 2, even cooperate with "single curved screw rod + PDC drill bit" combination, carries out the reaming operation, also because there is arc guide head 7 in the drill bit body front portion, has fine guide effect, can ensure that the drill bit is all the time in former well bore, plays the effect that effectively prevents out the new eye.

The cylindrical guide column 5 is shorter than the conical body of the pilot cone, the outer diameter is thicker, the strength is improved, the guide column cutting teeth 5a on the circumference of the cylindrical guide column 5 can directly cut broken rocks and are used for breaking collapsed strata and drilling new strata, and the tool can be matched with a screw rod and MWD drilling tool combination to perform full-size quick reaming. The pilot head central nozzle 7a and each bit body axial nozzle 4a are flushed downwards, blowing away the rock debris below.

And a guide column inclined lower nozzle 5b is arranged between every two adjacent guide column blades 6 respectively to prevent the guide column blades 6 from mud pack, so that the guide column blades can be used for breaking collapsed strata and drilling new strata, and the speed of reaming and drilling new strata is increased.

And the middle upper part of each drill bit chip groove 4 is provided with a drill bit body inclined upward nozzle 4b which is inclined upward by 45 degrees and is used for obliquely washing the diameter-reduced well wall upwards to form a diffuse water jet between the drill bit and the well wall, so that the mud pocket of the drill bit is effectively prevented from being scratched. In addition, turbulent flow is formed by the drilling fluid returning upwards from the inclined lower nozzle 5b of the guide column, and the drilling fluid is favorable for carrying rock debris to return upwards. All nozzles adopt pulse nozzles, and the jet impact capacity is maximized.

If in case of marking out a new hole, the cylindrical guide column 5 is similar to a small-diameter drill bit of a double-diameter drill bit, rock breaking is carried out in advance, stratum stress is released, then the guide column blade 6 breaks the stratum, then the PDC drill bit body 2 above the guide column blade is used for reaming drilling, so that new hole drilling can be directly carried out, old hole searching operation is carried out in cooperation with the single-bending screw and the wireless inclinometer while drilling, a pilot cone does not need to be replaced when the drill bit is started, and the drilling period is saved.

In a word, the tool can be used in combination with a screw and MWD drilling tool for reaming a long well section or finding an old well, can effectively avoid reaming a new well, prevent bit balling, has higher reaming speed, can effectively shorten the complex fault processing period in the well and save the drilling cost.

The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention. In addition to the above embodiments, the present invention may have other embodiments. All technical solutions formed by adopting equivalent replacement or equivalent transformation fall within the protection scope required by the utility model. The technical features of the present invention that have not been described can be realized by or using the prior art, and are not described herein again.

Claims

1. The utility model provides a reaming instrument of soft well section that easily collapses, includes the PDC drill bit body, the upper portion of PDC drill bit body is equipped with PDC drill bit screw thread, the lower part of PDC drill bit body is equipped with the coronal bottom, evenly be equipped with a plurality of blades on the coronal bottom, it has blade cutting teeth, its characterized in that to distribute on the blade: a cylindrical guide column extending downwards is arranged in the center of the bottom of the crown, an arc-shaped guide head is arranged at the bottom of the cylindrical guide column, a plurality of rows of guide column cutting teeth extending vertically are uniformly arranged on the circumference of the cylindrical guide column, and guide column downward-inclined nozzles are uniformly distributed on the circumference of the upper part of the cylindrical guide column; the middle section of the cylindrical guide column is symmetrically provided with three guide column blades, and two side walls of each guide column blade are respectively provided with blade cutting teeth.

2. A reaming tool for soft and collapsible intervals of a well according to claim 1, characterized in that: and drill bit body chip removal grooves are respectively arranged between the blades at the crown-shaped bottom, the lower parts of the drill bit body chip removal grooves are respectively provided with a drill bit body axial nozzle, and the middle upper parts of the drill bit body chip removal grooves are respectively provided with a drill bit body inclined upward nozzle.

3. A reaming tool for a soft and collapsible well section according to claim 1, characterized in that: the bottom of the arc-shaped guide head is provided with a horizontal cutting surface, and the center of the horizontal cutting surface is provided with a guide head center nozzle.

4. A reaming tool for a soft and collapsible well section according to claim 1, characterized in that: three blades are uniformly arranged on the circumference of the crown-shaped bottom.

5. A reaming tool for a soft and collapsible well section according to claim 1, characterized in that: the included angle between the axis of the guide column inclined downward nozzle and the axis of the cylindrical guide column is 45 degrees.

6. A reaming tool for soft collapsible intervals of a well according to claim 2, characterized in that: the included angle between the axis of the nozzle on the drill bit body in the inclined direction and the axis of the PDC drill bit body is 45 degrees.

7. A reaming tool for soft and collapsible intervals of a well according to claim 1, characterized in that: the distance between the top of the guide post blade and the coronal bottom is 0.15m.

8. A reaming tool for a soft and collapsible well section according to claim 1, characterized in that: the outer diameter of the guide column blade is 80% of the outer diameter of the blade, and the guide column obliquely downward nozzle is located between two adjacent guide column blades in phase.

9. A reaming tool for a soft, collapsible wellbore section according to claim 8, wherein: the thickness of guide post blade is greater than 15mm, and the width is less than 200mm.

10. A reaming tool for soft collapsible intervals of a well according to claim 2, characterized in that: and the guide column inclined lower nozzle, the drill bit body axial nozzle and the drill bit body inclined upper nozzle are all pulse nozzles.