CN216406749U - Hanger fracturing tieback instrument - Google Patents
Hanger fracturing tieback instrument Download PDFInfo
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- CN216406749U CN216406749U CN202121460055.2U CN202121460055U CN216406749U CN 216406749 U CN216406749 U CN 216406749U CN 202121460055 U CN202121460055 U CN 202121460055U CN 216406749 U CN216406749 U CN 216406749U
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Abstract
The utility model relates to a hanger fracturing tie-back tool which mainly comprises a hanger part and a sealing plug part matched with fracturing construction. The hanger part comprises a lifting short section, a pressing cap, a hanging barrel, sealing rubber, an object falling prevention mechanism, an expansion cone base, an expansion cone, a connecting rod, a fracturing tieback device, a casing short section, a rubber plug shearing mechanism, a well cementing rubber plug and the like, and the fracturing sealing plug part is of an integrated structure and mainly comprises the lifting short section, an upper sealing device face, a buckling structure, a lower sealing face and the like. After the hanger is hung in the upper-layer sleeve, a fracturing sealing plug is put in the hanger, and the hanger is inserted back to be connected with a fracturing tie-back device, so that fracturing operation can be performed. The utility model adopts the mode of combining the hanger and the fracturing sealing plug, has large drift diameter, good sealing performance and high bearing capacity, can meet various fracturing construction requirements, and can be widely applied to various oil-water well fracturing constructions.
Description
Technical Field
The utility model relates to the technical field of well drilling and completion in the petroleum and gas industry, and provides a hanger fracturing tie-back tool for later-stage fracturing construction. The utility model relates to the technical field of well drilling and completion in the petroleum and gas industry.
Background
The expansion hanger is a liner cementing tool combining steel pipe expansion seating and hanging and multiple sealing, the steel pipe is radially expanded through mechanical force or hydraulic pressure, and high-strength rubber materials are adopted for suspension sealing, so that a high-strength liner head sealing effect and a larger well completion inner diameter can be provided, water channeling is prevented, a casing pipe with a larger size than a conventional hanger can be suspended, and the requirement for running a large-diameter tool is met. In view of the technical advantages, the expansion hanger technology is widely applied to the fields of development of new wells, sidetracking of old wells, well repair and the like of oil fields, becomes an effective means for optimizing well body structures of new wells, increasing the inner diameter of well completion casings, suspending large-size casings for sidetracking wells for well completion and treating casing damage of long-stop wells, and becomes an effective technical support for improving benefits of oil fields.
However, the expansion hanger has a special principle structure design, and certain limitation is brought to the technical application of the expansion hanger, so that the development of the technology is limited. The expansion hanger radially expands the hanging cylinder body to achieve the engineering purpose of hanging sealing, the manufacturing material of the hanging cylinder is limited to be made of a steel pipe material with low strength and high plasticity, the high plasticity of the material determines that the original material can still keep mechanical properties such as compression resistance, tensile resistance and the like after the hanging cylinder is expanded, the low strength of the material can control the construction pressure of the hanger within a pressure range easy to implement on site, but the material strength can still achieve the performance index of API casing pipes commonly used in oil fields, and can meet the conventional development requirements of most oil-water wells. Because the pressure of fracturing construction in the later period of a development well of a low-permeability reservoir is often over 70 MPa, the compressive strength of the expansion hanger developed by related enterprises in China at present is generally low, and the expansion hanger cannot be used for the construction, so that the application limit of the expansion hanger completion technology in the low-permeability reservoir is caused. Aiming at the problem, the utility model designs the hanger fracturing tie-back tool, and the hanger which is designed by improving the structure can meet the fracturing construction requirements of most oil-water wells after being hung.
SUMMERY OF THE UTILITY MODEL
The utility model aims to solve the problem that the existing expansion hanger cannot meet the requirement of fracturing at the later stage of a low-permeability oil reservoir, and provides a hanger fracturing tie-back tool which not only keeps the advantages of the existing expansion hanger, but also can meet the requirement of oil-water well fracturing construction.
The utility model is realized by the following steps:
a hanger fracturing tie-back tool comprising:
the first lifting short section, the anti-falling mechanism, the base, the connecting rod, the rubber plug shearing mechanism and the well cementation rubber plug are sequentially connected from top to bottom;
the pressure cap, the suspension cylinder, the fracturing tieback device, the coupling and the casing pipe nipple are sequentially connected from top to bottom outside the first lifting nipple;
a reducing section is processed in the middle of the suspension cylinder, and an expansion cone is placed between the reducing part at the upper end of the reducing section and the base.
Further, the outer surface of the suspension cylinder is fixedly provided with sealing rubber in a vulcanization or mechanical mode.
Furthermore, the pressure cap is fixedly arranged on the outer surface of the first lifting short section through a pin and is in sealing fit with the upper end of the suspension cylinder.
Further, the rubber plug shearing mechanism and the well cementation rubber plug are fixed through pins.
Furthermore, an O-shaped sealing ring is arranged between the rubber plug shearing mechanism and the well cementation rubber plug.
Furthermore, the fracturing sealing plug is provided with an upper double sealing surface, a lower double sealing surface and a fracturing tie-back thread, and is used for performing fracturing operation in cooperation with the hanger cylinder and the fracturing tie-back device after well completion.
Furthermore, the suspension cylinder is made of a steel pipe material with low strength and high plasticity, and can generate radial cold-expanding plastic deformation under the action of hydraulic pressure or mechanical force.
Furthermore, the expansion cone is made of high-hardness steel such as tungsten steel and the like, and can enable the suspension cylinder to generate radial plastic deformation under the action of hydraulic pressure or mechanical force.
Furthermore, a V-shaped rubber cylinder is arranged on the outer surface of the falling object prevention mechanism, and the rubber cylinder and the inner wall of the suspension cylinder form interference fit.
Furthermore, the fracturing tie-back device is made of high-strength steel, an upper sealing surface, a tie-back female thread and a lower sealing surface are machined on the inner wall, and the tie-back female thread is a large-pitch low-torque left-hand flat-buckling female thread.
The utility model has the advantages that:
(1) the hanger suspension cylinder body is made of low-strength steel, but in the fracturing operation implementation project, the fracturing sealing plug is connected with the fracturing tieback device at the bottom of the suspension cylinder, so that high-pressure fluid can avoid the suspension cylinder body with weaker strength, and the processing cost and the manufacturing difficulty of the expansion hanger are reduced;
(2) the hanger can be used for hanging a casing pipe with a larger diameter than that of the conventional hanger, and is convenient for the implementation of later fracturing construction and various operations such as injection and production, sand prevention and the like;
(3) all mechanisms and fracturing sealing plugs of the inner pipe related to the structure can be recycled, so that the construction cost is greatly reduced.
Drawings
FIG. 1: is a schematic structural diagram of the hanger main body part.
FIG. 2: the utility model is a structural schematic diagram of the hanger after expansion sealing and mounting.
FIG. 3: the utility model is a structural schematic diagram of a fracturing sealing plug.
FIG. 4: is a structural schematic diagram of the fracturing implementation process.
In the figure: 1. the fracturing well cementing device comprises a suspension cylinder, 2, sealing rubber, 3, a fracturing tieback device, 4, a tieback female thread, 5, an upper sealing surface, 6, a lower sealing surface, 7, an expansion cone, 8, a base, 9, an object falling prevention mechanism, 10, a first lifting short section, 11, a pressing cap, 12, a connecting rod, 13, a rubber plug shearing mechanism, 14, a coupling, 15, a well cementing rubber plug, 16, a casing short section, 17, a fracturing sealing plug, 18, a second lifting short section, 19, an upper sealing ring, 20, a tieback male thread, 21 and a lower sealing ring.
Detailed Description
In order to explain technical features and objects of the present invention more clearly, embodiments of the present invention will be further described with reference to the accompanying drawings.
The first embodiment is as follows:
as shown in fig. 1-4, the utility model provides a hanger fracturing tie-back tool, which comprises a hanging cylinder 1, sealing rubber 2, a fracturing tie-back device 3, an expansion cone 7, a base 8, an object falling prevention mechanism 9, a first lifting short section 10, a pressing cap 11, a connecting rod 12, a rubber plug shearing mechanism 13, a coupling 14, a well cementation rubber plug 15, a casing short section 16 (shown in fig. 1), a fracturing sealing plug 17 (shown in fig. 3) and the like. A hang section of thick bamboo 1 and adopt the high plasticity steel of low strength to make, the mid portion adopts cold to expand technology processing reducing structure, hang 1 surface of a section of thick bamboo and vulcanize or mechanical system fixed seal rubber 2, seal rubber's quantity can be adjusted according to the actual demand condition, hang 1 lower extreme of a section of thick bamboo and pass through threaded connection fracturing tieback device 3, the device adopts high strength steel to make, inner wall processing upper seal face 5, tieback box thread 4, lower seal face 6, tieback box thread 4 is the flat female screw of detaining of the low moment of torsion left-hand of coarse pitch. The lower end of the fracturing tieback device 3 is connected with a casing nipple 16 through a coupling 14; the expansion cone 7 is placed on the base 8 and forms sealing fit, can be made of high-hardness alloy steel such as tungsten steel and is a key mechanism for the expansion sealing and seating of the hanger. 8 upper ends of base connect gradually and prevent junk mechanism 9, first promotion nipple joint 10, prevent junk mechanism 9 elementary structure for this external installation "V" shape rubber spare of metal, and hang and form interference fit between a body inner wall, its effect is for the hanger provides the protection during going into the well section of thick bamboo under, prevents that the solid phase impurity in the pit shaft from getting into and hanging a section of thick bamboo in, and first promotion nipple joint 10 function mainly is used for hanger cooperation drilling rod elevator to go into down. A pressure cap 11 is arranged between the first lifting short section 10 and the suspension cylinder 1, the pressure cap 11 is fixed on the outer surface of the first lifting short section 10 through a pin and forms a seal with the upper end of the suspension cylinder 1, and the secondary protection is mainly used for providing secondary protection for a hanger and preventing solid-phase foreign matters from entering the suspension cylinder 1; the lower end of the base 8 is sequentially fixedly connected with a connecting rod 12, a rubber plug shearing mechanism 13 and a well cementation rubber plug 15, a well is cemented between the rubber plug shearing mechanism 13 and the well cementation rubber plug 15 through pins, sealing elements such as an O-shaped ring and the like are installed, the well cementation rubber plug plays a role of completely pushing cement paste in a sleeve into an annular space between the sleeve and a well hole during well cementation, and the shearing working pressure of the rubber plug shearing mechanism 13 and the well cementation rubber plug 15 can be realized by adjusting the number of the pins. Fracturing sealing plug 17 formula structure as an organic whole, the upper end is second promotion nipple joint 18, and the lower extreme surface is last sealing washer 19, tieback pin thread 20, lower sealing washer 21 in proper order, and the tieback thread is the flat pin thread of detaining of coarse pitch low moment of torsion left-hand, and the effect is when later stage fracturing operation and 4 butt-joint tiebacks of tieback female thread of fracturing tieback device 3, satisfies the high-pressure sealed requirement simultaneously.
When the hanger fracturing tieback tool is implemented on site, firstly, the assembled hanger is connected to a casing string, as shown in figure 1, a drill pipe is conveyed to a designed well section in a tracing way, after the cementing operation is finished, the well mouth is thrown into a drill rod rubber plug, clean water or slurry is injected to continue the displacement operation, the drill rod rubber plug reaches the well cementing rubber plug 15, the fixing pin is cut off under the action of pressure, the well cementation rubber plug descends to the bottom of the casing and collides with the casing, the hydraulic pressure acting on the expansion cone 7 is continuously increased along with the increase of the pressure, the inner pipe is finally pushed to move upwards, at the moment, the suspension cylinder 1 generates radial deformation under the action of the expansion cone 7, because the deformation of the steel pipe is designed in the plastic deformation range, the suspension cylinder 1 can not generate resilience, after the expansion cone 7 completes the expansion operation of the whole suspension cylinder, the sealing rubber 2 is tightly compressed between the suspension cylinder 1 and the outer casing while providing a great suspension force as well as a sealing force.
As shown in fig. 2, after the inner pipe tool is pulled out, the hanger only retains the components such as the hanging cylinder 1, the sealing rubber 2, the fracturing tie-back device 3, the bottom casing short joint and the like in the shaft, and compared with a mechanical hanger, the hanger does not have mechanisms such as a hydraulic cylinder, a slip and the like, and provides a larger drift diameter for the shaft.
As shown in fig. 3-4, after the casing perforation operation is completed and the casing and the stratum channel to be fractured are established, a sealing ring is installed on the fracturing sealing plug 17, then a drill rod is used for conveying the fracturing sealing plug 17, and when the fracturing sealing plug 17 is lowered to be close to the expansion hanger, the lowering speed is controlled. When the fracturing sealing plug 17 is inserted into the hanging cylinder 1, the drilling rod is reversed mechanically or manually after the fracturing sealing plug is continuously lowered to meet 2 tons of resistance, and the torque is controlled within 25% of the back-off torque of the drilling rod, so that the back-off of the drilling rod is prevented. After the drill rod is reversely rotated for 5 circles, the drill rod is lifted upwards, after the suspended weight is increased by 3 tons compared with the original suspended weight of the drill rod, the fact that the tie-back male thread 20 of the fracturing sealing plug 17 is successfully buckled with the tie-back female thread 4 of the fracturing tie-back device 3 is shown, the suspended weight is adjusted to a value before buckling at the moment, the drill rod is continuously reversely rotated for 5 circles, the tie-back male thread 20 is completely matched with the tie-back female thread 4, and under the action of the upper sealing surface 5, the lower sealing surface 6, the upper sealing ring 19 and the lower sealing ring 21, high-pressure hydraulic sealing is generated between the fracturing sealing plug 17 and the fracturing tie-back device 3. Then, the ground fracturing equipment is utilized to pump the fracturing fluid into the stratum to be fractured through the drill rod, the fracturing sealing plug 17 and the sleeve in sequence, and the fracturing fluid can completely avoid the suspension cylinder 1 with weaker strength by adopting the fracturing mode for construction. After fracturing construction is completed, the drill rod is positively conveyed for 12 circles, the fracturing sealing plug 17 is separated from the fracturing tie-back device 3, the drill rod is lifted up, the hanging weight is recovered to the original hanging weight of the drill rod, the drill rod is continuously lifted up, the fracturing tool is lifted out of a wellhead, and fracturing operation is finished.
Example two:
a fracturing tieback tool of a hanger comprises a hanging cylinder 1, sealing rubber 2, a fracturing tieback device 3, an expansion cone 7, a base 8, an object falling prevention mechanism 9, a first lifting short section 10, a pressing cap 11, a connecting rod 12, a rubber plug shearing mechanism 13, a coupling 14, a well cementation rubber plug 15, a casing short section 16, a fracturing sealing plug 17 and the like; the suspension cylinder 1 is made of low-strength high-plasticity steel, the sealing rubber 2 is fixed on the suspension cylinder 1 body in a vulcanization or embedding fixing mode, the quantity of the sealing rubber 2 can be adjusted according to specific requirements, and rubber materials can be made of different rubber materials according to actual use requirements. The lower part of the suspension cylinder 1 is sequentially connected with a fracturing tieback device 3 and a casing nipple 16. The fracturing tie-back device 3 is made of high-strength steel to meet the fracturing construction requirement, an upper sealing surface 5, a tie-back female thread 4 and a lower sealing surface 6 are sequentially processed in the fracturing tie-back device 3 from top to bottom, wherein the tie-back female thread 4 is a large-pitch left-handed flat-thread, so that a tie-back operation link in a later implementation process is facilitated. An inner tube part of a hanger fracturing tieback tool sequentially comprises a first lifting short section 10, an anti-falling mechanism 9, a base 8, an expansion cone 7, a connecting rod 12, a rubber plug shearing mechanism 13 and a well cementation rubber plug 15 from top to bottom, wherein a V-shaped annular rubber part is arranged outside a body of the anti-falling mechanism 9, and forms interference fit with the inner wall of a body of a hanging cylinder 1. The expansion cone 7 is made of special materials such as tungsten steel and the like, the hardness of the expansion cone is higher than that of the suspension cylinder 1, one or more sealing ring grooves are formed in the inner wall of the expansion cone, and hydraulic sealing is formed between the expansion cone and the base 8 in a sealing ring mounting mode. The rubber plug shearing mechanism 13 is fixedly connected with the well cementation rubber plug 15 through pins, the number of the pins can be adjusted according to construction requirements, and meanwhile, sealing is carried out in a mode of installing a sealing ring. The fracturing sealing plug 17 is designed into an integral structure and is made of high-strength steel, a second lifting short section 18 is processed at the upper part, an upper sealing groove, a large-pitch low-torque left-handed flat-buckling male thread and a lower sealing groove are sequentially arranged at the lower part, a matched sealing rubber ring is arranged in the sealing groove,
the hanger fracturing tie-back tool firstly uses a hanger to connect a well completion casing to be put into a well, cement injection operation is completed, after cement slurry is replaced, the expansion cone 7 firstly moves upwards from the suspension cylinder 1 under the action of hydraulic or mechanical force, so that the body of the suspension cylinder 1 is subjected to plastic deformation, after the body is completely expanded, the hanger is seated on the inner wall of an upper layer casing, the functions of suspension and packing are realized simultaneously, and a drilling tool is lifted out of the expansion cone 7. And (3) continuing to run a second drilling tool, connecting the bottom of the drilling tool with a fracturing sealing plug 17, after the sealing plug is lowered into the inner cavity of the expansion hanger, realizing the buckling of the sealing plug and the fracturing tie-back device 3 through a reverse drilling tool, strictly controlling the torque in the buckling process, preventing the drill rod from being reversely buckled, and controlling the buckling torque within 25% of the drill rod unscrewing torque. After the buckling procedure is completed, because the sealing structure is processed between the sealing plug and the fracturing tie-back device 3, the fracturing pipe column and the sleeve form complete hydraulic sealing, the next fracturing operation can be continuously implemented, and the fracturing sealing plug 17 can be recycled after the fracturing operation is implemented. A hanger fracturing tieback instrument structural design succinct reliable, construction success rate is high, but inner tube instrument and fracturing seal plug 17 reality recycle, greatly reduced the operating cost, have wide market perspective.
The above description is only an exemplary embodiment of the present invention, and is not intended to limit the scope of the present invention. Any equivalent changes and modifications that can be made by one skilled in the art without departing from the spirit and principles of the utility model should fall within the protection scope of the utility model.
Claims (10)
1. A hanger fracturing tieback tool comprising:
the first lifting short section, the anti-falling mechanism, the base, the connecting rod, the rubber plug shearing mechanism and the well cementation rubber plug are sequentially connected from top to bottom;
the pressure cap, the suspension cylinder, the fracturing tieback device, the coupling and the casing pipe nipple are sequentially connected from top to bottom outside the first lifting nipple;
a reducing section is processed in the middle of the suspension cylinder, and an expansion cone is placed between the reducing part at the upper end of the reducing section and the base.
2. The hanger fracturing tie-back tool of claim 1, wherein the outer surface of the hanger barrel is vulcanized or mechanically secured with a sealing rubber.
3. The hanger fracturing tieback tool of claim 1, wherein the pressure cap is fixedly pinned to an outer surface of the first lifting sub and sealingly engages an upper end of the hanging barrel.
4. The hanger fracturing tie-back tool of claim 1, wherein the plug shearing mechanism is pinned to the cementing plug.
5. The hanger fracturing tie-back tool of claim 1, wherein an O-ring seal is installed between the plug shearing mechanism and the cementing plug.
6. The hanger fracturing tieback tool of claim 1, wherein the fracturing seal plug is provided with upper and lower double sealing surfaces and fracturing tieback threads for performing fracturing operations in cooperation with the hanger barrel and the fracturing tieback device after completion of a well.
7. The hanger fracturing tie-back tool of any one of claims 1 to 6, wherein the hanging cylinder is made of a steel pipe material with low strength and high plasticity, and can be subjected to radial cold-expanding plastic deformation under the action of hydraulic force or mechanical force.
8. The hanger fracture tie-back tool of any one of claims 1 to 6, wherein the expansion cone is made of tungsten steel and is capable of radially plastically deforming the hanging cylinder under hydraulic or mechanical force.
9. The hanger fracturing tie-back tool of any one of claims 1 to 6, wherein the anti-falling mechanism has a V-shaped rubber cylinder mounted on an outer surface thereof, and the rubber cylinder forms an interference fit with an inner wall of the hanger cylinder.
10. The hanger frac-tie-back tool of any one of claims 1-6, wherein the frac-tie-back device is made of high strength steel, the inner wall is provided with an upper sealing surface, a tie-back box thread and a lower sealing surface, and the tie-back box thread is a large pitch low torque left-hand flat-thread female thread.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121460055.2U CN216406749U (en) | 2021-06-30 | 2021-06-30 | Hanger fracturing tieback instrument |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121460055.2U CN216406749U (en) | 2021-06-30 | 2021-06-30 | Hanger fracturing tieback instrument |
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| CN216406749U true CN216406749U (en) | 2022-04-29 |
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| CN202121460055.2U Active CN216406749U (en) | 2021-06-30 | 2021-06-30 | Hanger fracturing tieback instrument |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117868803A (en) * | 2024-03-13 | 2024-04-12 | 中石化西南石油工程有限公司 | Four-combined test pipe column suitable for ultra-deep well oil and gas well and use method thereof |
-
2021
- 2021-06-30 CN CN202121460055.2U patent/CN216406749U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117868803A (en) * | 2024-03-13 | 2024-04-12 | 中石化西南石油工程有限公司 | Four-combined test pipe column suitable for ultra-deep well oil and gas well and use method thereof |
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