CN116255089A - Equal-well-diameter drilling tool for realizing casing tie-back and operation method thereof - Google Patents

Abstract

The invention discloses an equal-well-diameter drilling tool for realizing casing tie-back and an operation method thereof, belonging to the technical field of oilfield drilling engineering. Meanwhile, the invention also discloses an operation method of the constant-diameter drilling tool for realizing casing tie-back. The invention adopts the equal-diameter casing tie-back drilling method to repair, can continue drilling by the original drill bit, ensures that the subsequent well structure is unchanged, can achieve the purpose of drilling without loss of well diameter, and can effectively solve the problems that deep wells and ultra-deep wells cannot effectively drill to a target layer due to excessive casing layers, oil production pipe columns have small inner diameter, low oil production efficiency and the like.

Description

Equal-well-diameter drilling tool for realizing casing tie-back and operation method thereof

Technical Field

The invention relates to the technical field of oilfield drilling engineering, in particular to an equal-well-diameter drilling tool for realizing casing tie-back.

Background

The equal-well-diameter drilling technology is a continuation of an expansion pipe technology, and utilizes the equal-well-diameter expansion pipe technology as an emergency measure in the drilling process to form a temporary well wall to block complex stratum without losing the inner diameter of a well hole, so that the well structure is optimized and perfected, and the purpose of drilling is achieved. The technique can adopt the same drilling tool specification to drill in the next drilling process, achieves the aim of finally completing the well hole to be larger, improves the drilling period as much as possible and saves the drilling cost.

The equal diameter drilling technology is a major breakthrough in the design of the well bore, can realize the reduction of the well diameter of the well section at the middle part and the upper part, can maintain or enlarge the original well completion size, reduce the well diameter loss caused by the influence of the well bore, and can drill the well deeper and obtain larger well completion inner diameter.

The equal-well-diameter drilling sleeve tieback technology and the matched tool are key single technology and tool of the equal-well-diameter drilling technology, and the equal-well-diameter of the whole well shaft can be finally realized through the equal-well-diameter drilling sleeve tieback technology and the matched tool. Currently, the constant diameter drilling technology mainly performs one-section or multi-section plugging on an open hole section, and continuous constant diameter plugging cannot be realized.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provides an equal-well-diameter drilling tool for realizing casing tie-back and an operation method thereof, which are used for plugging an unstable stratum in an open hole section without changing the original well structure. The construction scheme and the site construction operation of the tie-back drilling of the constant-diameter sleeve are guided to be formulated, the construction process and the construction tool combination are optimized, and the technical problem of tie-back of the constant-diameter drilling sleeve is solved, so that the zero-loss drilling of the inner diameter of the whole shaft is realized, the structure of the well body can be effectively optimized, the operation cost is reduced, and the aims of reducing the cost and enhancing the efficiency are fulfilled.

Embodiments of the present invention are implemented as follows:

in one aspect, the embodiment of the invention provides an equal-well diameter drilling tool for realizing casing tie-back, which comprises a variable-diameter casing shoe 1, a variable-diameter expansion tool string 2, a casing 9, a drill rod 10, a reamer 11, a rubber plug 12, a packer 13, a grinding shoe 15 and a drill bit 16, wherein the variable-diameter casing shoe 1 is arranged at the lower part of the casing 9, and mainly plays a role of finishing the suspension of a lower expansion pipe and the sealing of an annulus by being attached to the packer. The variable diameter expansion tool string 2 is used for expanding an expansion pipe and consists of a variable diameter expansion cone, an expansion executing mechanism and the like, and can meet the requirement of small-diameter running-in and large-diameter expansion. The reducer casing shoe 1 is connected with a casing 9 through threads on a casing collar 8.

In the preferred embodiment of the present invention, the reducing expansion tool string 2 is composed of an expansion pipe 3, a drill pipe 4, an expansion actuator 5, a reducing cone 6 and a cementing accessory 7. The variable diameter expansion tool string 2 is divided into an inner tubular column and an outer tubular column. The inner pipe column consists of an expansion executing structure 5 and a reducing cone 6. The outer pipe column consists of a well cementation accessory 7 and an expansion pipe 3. The outer tubular column cementing accessory 7 is connected with the expansion pipe 3 through threads. The inner pipe column reducing cone 6 is connected with the execution structure 5 through threaded sleeves at two ends.

Further, the packer 13 is installed in the upper part of the expansion pipe 3. The expansion pipe packer is used for hanging with the reducer casing shoe, so that the expansion pipe packer section is effectively sealed.

In the preferred embodiment of the present invention, the packer 13 is provided with an outer rubber 14.

The technical effect achieved is that the outer rubber 14 of the packer has the function of suspending the lower expansion pipe and sealing the annulus.

The technical effect that it reaches is through the laminating of hanger outer rubber 14 and reducing sleeve shoes 1 inner wall, bears the weight of lower part expansion pipe, prevents that the expansion pipe from taking place the landing when cement does not solidify. And the effective sealing of the annular space is ensured, and the normal operation of the subsequent construction is ensured.

In the preferred embodiment of the present invention, the reamer 11 adopts a ball-throwing open mode, the blade is in the body when the construction section is not reached, and when the construction section is reached, the start ball is thrown in from the wellhead, and the reamer is opened to perform reaming operation.

After the expansion operation is completed, the inner diameter of the expanded pipe 3 coincides with the inner diameter of the casing 9. Drilling may continue using the original drill bit.

In another aspect, embodiments of the present invention provide a method of operating an equal borehole drilling tool for casing tieback, comprising the steps of:

step 1, reducing sleeve shoe is put in: the reducer casing shoe is connected with the upper casing on the ground, then is lowered to a design position along with the upper casing according to normal casing lowering operation, and well cementation is carried out on the upper casing according to conventional well cementation operation after reaching the design position. The inner diameter of the reducer casing shoe is larger than that of the upper casing. The length of the reducer sleeve shoe is determined according to the length of the expansion pipe which is needed to be hung, so that enough hanging force and sealing capability during tie-back are ensured.

Step 2, reaming operation: and (3) the reaming tool is put into to perform sizing reaming operation on the section to be sealed, and the reaming diameter is set according to expansion pipes with different specifications and well cementation and non-well cementation modes.

Step 3, inserting a variable-diameter expansion pipe tool string: the tool string of the reducing expansion pipe is arranged at a designated position through the drill rod, and the tool string comprises an expansion pipe, the reducing expansion tool string and other functional accessories;

step 4, cementing and expansion operation: after the tool string is put into place, well cementation operation is carried out according to actual needs, after cement paste is pumped in, a pressure-holding ball or a rubber plug is put in to hold pressure, and when the pressure reaches the expansion starting pressure, expansion starts. And after the expansion is finished, the packer is attached to the reducer casing shoe to form a seal. When the well cementation is not needed, the pressure-building ball or the rubber plug is directly put into the well cementation, and the pressure-building ball or the rubber plug starts to expand.

Step 5, communicating borehole operation: and after the expansion is finished, the drill rod is put into a grinding shoe to perform grinding and milling operation on the lower well cementation accessory, so as to communicate with the lower well bore.

Step 6, drilling operation: after the well communication is completed, the grinding shoes are lifted out, and the drill bit is put in to start normal drilling.

The embodiment of the invention has the beneficial effects that:

the invention provides an equal-well-diameter drilling tool for realizing casing tie-back and an operation method thereof, and compared with the prior art, the equal-well-diameter drilling tool has the advantages that: after the unstable stratum of the open hole section is plugged, the original drill bit can be used for continuously drilling, and the original well structure is not changed; the deep well and the ultra-deep well have too many casing layers to effectively drill the target layer, and the casing layer sequence is reduced by adopting the equal-well-diameter casing tie-back technology, so that the casing layer sequence is reserved for effectively drilling the target layer; the diameter of the tail pipe well completion is too small, and the oil extraction rate is low. By adopting the equal-well-diameter casing tie-back drilling technology, the diameter of the tail pipe is increased, the contact area between the tail pipe and an oil layer is enlarged, and the oil extraction rate is improved.

After the restoration is completed, the wall thickness and the inner diameter of the expansion pipe can be reduced by 2 because the expansion pipe and the upper casing are hung, so that the subsequent drilling can not be carried out according to the original well structure. After the repairing by adopting the equal-diameter casing tie-back drilling method, the original drill bit can continue to drill, and the subsequent well body structure is ensured to be unchanged. In addition, the technology of the invention is combined with the multi-section equal-diameter technology for carrying out the multi-section equal-diameter casing tie-back technology, thereby achieving the purpose of drilling without loss of well diameter, and effectively solving the problems that deep wells and ultra-deep wells cannot be effectively drilled to a target layer due to excessive casing layers, the oil production pipe column has small inner diameter, low oil production efficiency and the like. Finally, the technology can effectively reduce the dosage of the casing and the well cementation cement and can effectively reduce the construction cost.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of a reduced casing shoe construction;

FIG. 2 is a schematic diagram of a variable diameter expansion tool string;

FIG. 3 is a schematic view of upper casing and variable diameter casing shoe down;

FIG. 4 is a schematic illustration of a reaming operation;

FIG. 5 is a schematic view of a reducing expansion tool string run in;

FIG. 6 is a schematic diagram of the operation of a variable diameter expansion tool string;

FIG. 7 is a schematic diagram of an end-of-well casing tieback technique;

FIG. 8 is a schematic illustration of a communication lower wellbore;

fig. 9 is a schematic view of the continued drilling of the drill bit.

In the figure: 1-reducer casing shoes, 2-reducer expansion tool strings, 3-expansion pipes, 4-drill pipes, 5-expansion actuators, 6-reducer cones, 7-well cementation accessories, 8-casing joints, 9-casings, 10-drill pipes, 11-reamers, 12-rubber plugs, 13-packers, 14-packer rubbers, 15-grinding shoes, 16-drills, 17-blades, 18-standard casing buttons and 19-well cementation cements.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments of the present invention. The components of the embodiments of the present invention generally described and illustrated in the figures herein can be arranged and designed in a wide variety of different configurations.

Referring to fig. 1, a standard sleeve fastener 18 is used at the rear of the reducer sleeve shoe 1 to facilitate connection with an upper sleeve. The expansion length A and the expansion diameter B are determined by the specification, the length and the weight of the lower hanging expansion pipe.

Referring to fig. 2, the reducing expansion tool string 2 is composed of an expansion pipe 3, a drill rod 4, an expansion actuator 5, a reducing cone 6 and a well cementation accessory 7. The drill rod 4 plays a role in lifting and lowering. When the expansion starts, the expansion pipe actuator pushes the reducing cone 6 to start the expansion by the hydraulic action. The well cementing accessory 7 is used in a well cementing operation.

After the expansion operation is completed, the inner diameter of the expanded pipe 3 coincides with the inner diameter of the casing 9. Drilling may continue using the original drill bit. For example: the upper casing is 95/8' (the inner diameter is larger than phi 220.5 mm) and is planned to be drilled by a phi 215.9mm drill bit. After the expansion pipe with the specification of 203 is adopted, the inner diameter after expansion can reach phi 218mm, and the original phi 215.9mm drill bit can continue drilling.

Referring to fig. 3, a variable diameter casing shoe 1 is connected to casing 9 by casing collar 8 and is run into the well using a normal casing running procedure. And after the well is put in place, adopting a normal well cementation operation mode to perform well cementation.

Referring to fig. 4, after the well cementation operation is completed, the drilling is continued, after the drilling is completed, the reamer 11 is used for reaming the well section to be plugged, the reamer 11 is lowered through the drill rod 10, and after the reamer 11 is lowered to a designated position, the blades 17 in the reamer 11 extend out for reaming. After reaming is completed, reamer retract blades 17, which are retracted by drill pipe 10.

Referring to fig. 5, after the reaming is completed, the variable diameter expansion tool 2 is lowered to a designated position through the drill pipe 10.

Referring to fig. 6, after the diameter-variable expansion tool 2 is put into place, the cementing operation is performed, after the cementing operation is completed, the rubber plug 12 is put into the pipe body, the rubber plug 12 is driven by the drilling fluid to be pumped into place, and then the pressure is increased. And continuously pressing to reach expansion pressure, and driving the expansion executing mechanism 5 to drive the reducing expansion cone 6 to start working to start expanding the expansion pipe 3 by pressure.

Referring to fig. 7, after inflation is completed, the packer 13 is fitted with the variable diameter casing shoe 1. The outer packer rubber 14 has the effect of suspending the lower expansion tube and sealing the annulus. After completion, the inner diameter A of the upper sleeve is consistent with the inner diameter B of the lower expansion pipe. The original drill bit can be used for continuous drilling without changing the original well structure.

Referring to fig. 8, a running mill shoe 15 is shown to mill the well cementing accessory 7 and communicate with the lower wellbore.

Referring to fig. 9, the run-in bit 16 continues to drill.

The embodiment proves that the technology can effectively reduce the dosage of the casing and the well cementation cement 19 and can effectively reduce the construction cost.

It is to be understood that the above-described embodiments of the present invention are merely illustrative of or explanation of the principles of the present invention and are in no way limiting of the invention. Accordingly, any modification, equivalent replacement, improvement, etc. made without departing from the spirit and scope of the present invention should be included in the scope of the present invention. Furthermore, the appended claims are intended to cover all such changes and modifications that fall within the scope and boundary of the appended claims, or equivalents of such scope and boundary.

Claims (6)

1. The utility model provides an equiwell diameter drilling tool for realizing casing tie-back, its characterized in that includes reducing casing shoes (1), reducing expansion tool cluster (2), sleeve pipe (9), drilling rod (10), reamer (11), plug (12), packer (13), mill shoes (15) and drill bit (16), the lower part at sleeve pipe (9) is installed in reducing casing shoes (1), reducing casing shoes (1) are connected with sleeve pipe (9) through the screw thread on sleeve pipe coupling (8).

2. The equal-diameter drilling tool for realizing casing tie-back according to claim 1, wherein the reducing expansion tool string (2) consists of an expansion pipe (3), a drill rod (4), an expansion actuating mechanism (5), a reducing cone (6) and a well cementation accessory (7), the reducing expansion tool string (2) is divided into an inner pipe column and an outer pipe column, the inner pipe column consists of the expansion actuating mechanism (5) and the reducing cone (6), the outer pipe column consists of the well cementation accessory (7) and the expansion pipe (3), the outer pipe column well cementation accessory (7) is connected with the expansion pipe (3) through threads, and the inner pipe column reducing cone (6) is connected with the actuating mechanism (5) through threaded sleeves at two ends.

3. The equal borehole drilling tool for casing tieback according to claim 2, characterized in that the packer (13) is mounted in the upper part of the expansion pipe (3).

4. A constant bore drilling tool for casing tieback according to claim 3, characterised in that the packer (13) is provided with an outer packer rubber (14) for sealing with the variable diameter casing shoe (1).

5. The constant diameter drilling tool for casing tieback according to claim 1, wherein after completion of the expansion operation the inner diameter of the expansion pipe (3) corresponds to the inner diameter of the casing (9) and drilling is continued using the original drill bit.

6. A method of operating the constant bore drilling tool for casing tieback of claim 1 comprising the steps of:

step 1, reducing sleeve shoe is put in: after the ground is connected with the upper sleeve, the reducer casing shoe is lowered to a design position along with the upper sleeve according to normal casing lowering operation, and after reaching the design position, the upper sleeve is well fixed according to conventional well cementation operation; the inner diameter of the reducer casing shoe is larger than that of the upper casing; the length of the reducer casing shoe is determined according to the length of the expansion pipe which is needed to be hung, so that enough hanging force and sealing capability during tie-back are ensured;

step 2, reaming operation: the reaming tool is put into to perform sizing reaming operation on the section to be sealed, and the reaming diameter is set according to expansion pipes with different specifications and well cementation and non-well cementation modes;

step 3, inserting a variable-diameter expansion pipe tool string: the tool string of the reducing expansion pipe is arranged at a designated position through the drill rod, and the tool string comprises an expansion pipe, the reducing expansion tool string and other functional accessories;

step 4, cementing and expansion operation: after the tool string is put in place, performing well cementation operation according to actual needs, pouring a pressure-holding ball or a rubber plug after cement paste is pumped in, and starting expansion when the pressure reaches the expansion starting pressure; after expansion is finished, the packer is attached to the reducer casing shoe to form a seal; when the well cementation is not needed, directly putting a pressure-building ball or a rubber plug into the well, and starting expansion of the pressure building ball or the rubber plug;

step 5, communicating borehole operation: after expansion is completed, a grinding shoe is put into the drill rod to mill the lower well cementation accessory, so as to communicate with the lower well bore;

step 6, drilling operation: after the well communication is completed, the grinding shoes are lifted out, and the drill bit is put in to start normal drilling.

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