CN219220295U

CN219220295U - Whipstock for sidetracking

Info

Publication number: CN219220295U
Application number: CN202222909110.2U
Authority: CN
Inventors: 陈忠帅; 裴学良; 刘志和; 庄伟�; 孙艳军; 刘峰
Original assignee: Sinopec Oilfield Service Corp; Sinopec Shengli Petroleum Engineering Corp; Drilling Technology Research Institute of Sinopec Shengli Petroleum Engineering Corp
Current assignee: China Petroleum and Chemical Corp; Sinopec Oilfield Service Corp; Sinopec Shengli Petroleum Engineering Corp; Drilling Technology Research Institute of Sinopec Shengli Petroleum Engineering Corp
Priority date: 2022-11-02
Filing date: 2022-11-02
Publication date: 2023-06-20
Anticipated expiration: 2032-11-02

Abstract

The utility model relates to a whipstock for sidetracking, which comprises a guide bevel body connected to a drill string, wherein an arc-shaped guide bevel surface is constructed at the axial upper part of the guide bevel body; and the milling cone is arranged at the upper end of the inclined guide body, can move relative to the inclined guide body along the inclined surface, and can be converted into an inclined state from a vertical state so as to form a branch well hole. The inclined body is internally provided with a central tube, and the lower end of the central tube is provided with a liquid inlet communicated with a vertical well hole. The guide slope is made of a perforating material penetrable by the perforating gun so that the guide slope can form a channel communicated with the branch wellbore, and the upper end of the central tube body is arranged to extend to the guide slope.

Description

Whipstock for sidetracking

Technical Field

The utility model relates to a whipstock for sidetracking.

Background

In drilling operation, a multi-branch well refers to that a plurality of branch wellbores entering a reservoir are drilled at the fundus part of a main well, so that a plurality of hydrocarbon reservoirs can be produced in the main well, and multi-target and three-dimensional production of one well can be realized. From the drilling perspective, the branch well bores share the wellhead and the upper well section, so that the occupation area of the wellhead and the supporting equipment can be reduced, and the moving procedure of the oil well is simplified, thereby reducing the total drilling cost, improving the comprehensive economic benefit of oil gas development, and being a drilling technology with the potential of cost reduction and efficiency enhancement.

In the drilling process of the branch well, an operator needs to use a whipstock to perform pre-windowing operation on the side wall of the main well hole, then a drilling tool is put into the drilling tool to perform drilling and well cementation operation of the branch well, and finally the main well hole and the branch well hole are drilled through by the lower incidence hole device.

The existing whipstock needs to drill down for multiple times in pre-windowing operation and drilling operation, so that the operation flow is complex, and the operation time is long. Meanwhile, the existing whipstock cannot realize accurate positioning in a well drilling tool and a perforating device, so that multiple times of adjustment are needed, the complexity of the operation flow is further increased, and meanwhile, the operation time is prolonged.

Disclosure of Invention

The utility model aims to solve the technical problems described above and provides a whipstock for sidetracking. The whipstock for side drilling can realize single trip, thereby effectively simplifying operation steps and reducing operation time.

According to a first aspect of the present utility model, there is provided a whipstock for sidetracking comprising a lead screw attached to a drill string, the lead screw having an arcuate lead screw formed at an axially upper portion thereof; and the milling cone is arranged at the upper end of the inclined guide body, can move relative to the inclined guide body along the inclined surface, and can be converted into an inclined state from a vertical state so as to form a branch well hole.

The central pipe body capable of being closed by the inclined guide surface is arranged in the inclined guide body, and the lower end of the central pipe body is provided with a liquid inlet communicated with the vertical well hole. The guide slope is made of a perforating material penetrable by the perforating gun so that the guide slope can form a channel communicated with the branch wellbore, and the upper end of the central tube body is arranged to extend to the guide slope.

In a preferred embodiment, an anchor assembly capable of separating a wellbore is also included at the lower end of the lead, the anchor assembly including a packer and a pressure transfer line communicating the packer with the drill string.

In a preferred embodiment, a through hole allowing the central tube to pass through is arranged in the packing cylinder, a closed annular gap is formed between the central tube and the packing cylinder, and a piston capable of moving under the action of pressure is arranged in the annular gap.

The outer wall of the packing cylinder is respectively provided with a slip and a sealing rubber cylinder, and the slip and the sealing rubber cylinder can be opened along the radial direction under the pushing of the piston.

In a preferred embodiment, a cavity is arranged in the milling cone, the upper end of the cavity is communicated with a drill string, and the lower end of the cavity is communicated with the pressure transmission pipeline.

A seal separating the cavity from the outer space of the milling cone is provided in the cavity, the seal being provided as a rupture disc which can rupture under pressure.

In a preferred embodiment, a positioning assembly is also included, the positioning assembly including a radiation source disposed on the lead screw, and a signal receiver connectable to the drill string.

In a preferred embodiment, a groove is provided in the outer wall of the oblique body, the radiation source being arranged in the groove, and a plug closing the groove being further arranged in the groove.

In a preferred embodiment, the grooves are provided in two, which are respectively provided on the outer walls of the upper and lower sides of the guide rail.

In a preferred embodiment, a through groove penetrating through the oblique body along the axial direction is arranged on the outer wall of the oblique body, the pressure transmission pipeline is arranged in the through groove, and a strip-shaped baffle plate for sealing the through groove is further arranged on the through groove. The through groove is arranged on one side, far away from the guide inclined plane, of the guide inclined plane.

In a preferred embodiment, the slips include anti-drop slips and anti-rotation slips having elongated and diamond-shaped slip teeth, respectively, disposed thereon.

In a preferred embodiment, a support rod mounting hole penetrating the ramp in the radial direction is further provided on an outer wall of an axially upper portion of the ramp.

In a preferred embodiment, the oblique guide body is connected with the milling cone by a suspension pin which can be sheared off.

Drawings

The present utility model will be described below with reference to the accompanying drawings.

FIG. 1 shows a schematic view of a whipstock for sidetracking a wellbore according to one embodiment of the utility model.

FIG. 2 is a schematic illustration of a sidetrack drilling performed by the whipstock for the sidetrack drilling shown in FIG. 1.

Fig. 3 is a rear view of the guide diagonal of the whipstock for sidetracking shown in fig. 1.

In this application, all of the figures are schematic drawings which are intended to illustrate the principles of the utility model and are not to scale.

Detailed Description

The utility model is described below with reference to the accompanying drawings.

FIG. 1 shows a schematic view of a whipstock 100 for sidetracking in accordance with an embodiment of the utility model. As shown in fig. 1, the whipstock 100 for sidetracking includes a cylindrical deflector 10. A milling cone 20 is provided at the upper end of the bevel gear 10. The deflector 10 is connected to a down-hole drill string 21 by a milling cone 20 so as to be lowered into the well along with the drill string 21.

The milling cone 20 is connected to the ramp 10 by a shearable hanger pin 22. When the suspension pin 22 is sheared, the milling cone 20 can move downwards relative to the oblique body 10 under the drive of the drill string 21. Meanwhile, an arc-shaped guide inclined surface 12 is formed at the upper part of the axial direction, which is connected with the milling cone 20, of the guide inclined body 10. Thus, during the downward movement of the milling cone 20, the guiding inclined plane 12 can change the movement direction of the milling cone 20, so that the milling cone 20 can drill into the stratum obliquely to form branch wellbores, thereby completing the pre-opening window operation of the sidetrack well.

Fig. 2 is a schematic diagram of a sidetrack drilling performed by the whipstock 100 for the sidetrack drilling shown in fig. 1. As shown in fig. 2, after formation of the lateral wellbore 15, an operator may raise the milling cone 20 out of the wellbore 16 and then lower a drilling tool (not shown) to perform a drilling operation, and after the drilling operation is completed, a new lateral 151 may be formed through a cementing operation.

As shown in fig. 2, in the present utility model, a central pipe body 14 is disposed in the inclined guide body 10, a lower end of the central pipe body 14 is formed as a liquid inlet 141 communicating with a vertical well bore, and an upper end is disposed to extend to the inclined guide surface 12 and can be closed by the inclined guide surface 12. Meanwhile, the guide slope 12 is made of a perforating material that can be penetrated by a perforating gun. Thus, when the lateral well 151 is well-fixed, the operator can insert the perforating gun 121 into the well to perform perforating operation on the inclined guide surface 12, and the channel 152 for communicating the vertical well bore and the lateral well 151 is formed through the perforating operation. After the passage 152 is formed, an operator can run a production pipe (not shown) which communicates with the vertical well and the branch well 151 simultaneously into the wellbore, and control the production pipe to perform the combined production or the separate production of the vertical well and the branch well 151.

It should be noted that the structure and principle of such a riser are well known to those skilled in the art, and detailed description thereof will be omitted herein.

As shown in fig. 1, the whipstock 100 for sidetracking according to the present utility model further comprises an anchor assembly 30 provided at the lower end of the lead screw 10. The anchor assembly 30 includes a packer 40 configured to seal the wellbore under hydraulic pressure.

As shown in fig. 1, the packing cylinder 40 is provided in a cylindrical shape, a through hole 41 allowing the central tube 14 to pass through is provided in the packing cylinder 40, and the central tube 14 passes through the packing cylinder 40 through the through hole 41 so as to extend to the bottom of the vertical well. Slip 42 for sitting and hanging and rubber cylinder 44 capable of sealing the well bore are respectively arranged on the outer wall of the packer cylinder 40. The slips 42 and the packing element 44 can be opened by pressure from the pressure line 50 to complete the setting and packing operations.

An annular gap 45 is formed between the central tube 14 and the packing sleeve 40 in a radial direction. The upper and lower ends of the annular gap 45 are closed by the outer wall of the packing casing 40, respectively, so that the gap 45 is formed as a closed liquid chamber 451, and a piston 452 capable of being connected to the slips 42 and the packing casing 44 is provided in the liquid chamber 451. When fluid under high pressure enters the fluid chamber 451, the piston 452 is capable of moving within the fluid chamber 451 under hydraulic pressure, thereby moving from an initial first position to a second position, and after the piston 452 moves to the second position, the piston 452 is capable of pushing the slips 42 and the packing 44 open. While the construction and movement of such pistons 452 are well known to those skilled in the art, a detailed description thereof will be omitted herein.

Meanwhile, a one-way locking mechanism (not shown) is further arranged between the piston 452 and the liquid cavity 451, and the piston 452 is connected with the side wall of the liquid cavity 451 through the one-way locking mechanism. The one-way locking mechanism may be, for example, a ratchet. When the slips 42 and the barrel 44 are open, the one-way locking mechanism secures the piston 452 from moving from the second position to the first position, thereby preventing the slips 42 and the barrel 44 from retracting, causing the anchor assembly 30 to fail.

In a preferred embodiment, the slips 42 include anti-drop slips 422 and anti-spin slips 424, with different slip teeth (not shown) disposed on the anti-drop slips 422 and anti-spin slips 424, respectively. In particular, the slip teeth of the drop slips 422 are configured in an elongated shape such that the drop slips 422 are better able to prevent axial movement between the packer 40 and the wellbore. The slip teeth of the anti-rotation slips 424 are diamond shaped such that the anti-rotation slips 424 better prevent circumferential rotation between the packer 40 and the wellbore. Through the mode that prevents falling slips 422 and prevent changeing slips 424 and combine together, both can reduce the drill string 21 and seal the interference of packing box 40 when axial displacement in the pit shaft, can reduce the drill string 21 again and rotate the interference to packing box 40 to make packing box 40 have better anchoring effect.

As shown in fig. 1, the anchor assembly 30 includes a pressure transfer line 50 configured to transfer hydraulic pressure into the liquid chamber 451. A cavity 26 is arranged in the milling cone 20, the upper end of the cavity 26 is communicated with the drill string 21, and the lower end of the cavity 26 is communicated with the pressure transmission pipeline 50. The upper end of the pressure transmission line 50 is communicated with the drill string 21 through the cavity 26, and the lower end of the pressure transmission line is communicated with the liquid cavity 451, so that high-pressure fluid in the drill string 21 can be introduced into the liquid cavity 451 to push the piston 452 to move.

Further, a seal 28 is provided in the cavity 26 to separate the cavity 26 from the outer space of the milling cone 20. The seal 28 is provided as a rupture disc which is capable of rupturing under pressure. The rupture pressure of the rupture disc is set to be greater than the packing pressure of the slips 42 and the packing 44. Thus, after the piston 452 has moved to the second position, the operator may continue to press, increasing the pressure within the drill string 21, until the rupture disc ruptures under pressure. At this time, the high pressure fluid moves to the outer space of the milling cone 20 through the milling cone 20, so that the pressure of the drill string 21 and the liquid chamber 451 is released, and the high pressure of the drill string 21 and the liquid chamber 451 is prevented from affecting the normal drilling operation.

Fig. 3 is a rear view of the deflector 10 of the whipstock 100 for sidetracking shown in fig. 1. As shown in fig. 3, the pressure transfer line 50 is disposed outside the incliner 10. The diameter of the upper end of the ramp 10 is small due to the presence of the ramp 12 at the upper part of the ramp 10. Thus, by disposing the pressure transfer line 50 outside the inclinometer 10, the pressure transfer line 50 can be effectively prevented from interfering with the disposition of the central tube 14 within the inclinometer 10, while also preventing the high pressure fluid of the pressure transfer line 50 from flowing into the central tube 14 through the pressure transfer line 50 under the extreme condition of rupture of the pressure transfer line 50, interfering with the normal operation of the inclinometer 100.

As shown in fig. 3, a through groove 18 penetrating the ramp 10 in the axial direction is provided in the outer wall of the ramp 10. The pressure transfer line 50 is disposed in the through groove 18 so that the pressure transfer line 50 is mounted on the outer wall of the incliner 10. Meanwhile, a long-strip-shaped baffle (not shown) for closing the through groove 18 is also provided on the through groove 18. The baffle can close the through groove 18, thereby preventing the pressure transfer line 50 from being separated from the outer wall of the chute 10. And, the through groove 18 is provided at a side of the ramp 10 away from the ramp 12. With this arrangement, the milling cone 20 can be prevented from contacting the pressure transmitting line 50 when the milling cone 20 moves along the guide slope 12, causing damage to the pressure transmitting line 50.

As shown in fig. 3, in a preferred embodiment, a support rod mounting hole 19 is further provided on an outer wall of an axially upper portion of the guide body 10, and the support rod mounting hole 19 penetrates the guide body 10 in a radial direction. In this way, a supporting rod (not shown) may be inserted into the inclinator 10 through the supporting rod mounting hole 19, so that the entire whipstock 100 for sidetracking is suspended and fixed at the wellhead by the supporting rod, thereby further facilitating the assembling work of the whipstock 100 at the wellhead.

As shown in fig. 1, the whipstock 100 for sidetracking according to the present utility model further comprises a positioning assembly 60 provided on the deflector 10. The positioning assembly 60 includes a radiation source 64 disposed on an outer wall of the lead screw 10, the radiation source 64 capable of producing a radiation signal downhole. Meanwhile, the positioning assembly 60 further includes a signal receiver (not shown) disposed on the drill string 21, the signal receiver being capable of receiving the radiation signal generated by the radiation source 64 and transmitting the radiation signal to the wellhead. Thus, when the pre-windowing operation is completed, during the process of putting down the drilling tool or the perforating gun 121, an operator can confirm the relative position between the drilling tool or the perforating gun 121 and the oblique guide body 10 through the signal receiver, so that the accurate positioning between the drilling tool or the perforating gun 121 is facilitated.

Specifically, a groove 66 is provided on the outer wall of the oblique body 10, and the radiation source 64 is disposed in the groove 66. A plug 68 is also provided within the recess 66, it being readily understood that the recess 66 can be closed by the plug 68 to prevent the radiation source 64 from escaping.

In a preferred embodiment, the grooves 66 are provided in two, which are provided on the outer walls of the upper and lower sides of the guide rail 10, respectively. The accuracy of the positioning can be further improved by the secondary positioning of the radiation source 64 in the upper and lower recesses 66.

The operation of the whipstock 100 for sidetracking according to the present utility model is briefly described as follows.

The whipstock 100 for sidetrack drilling of the present utility model is used for drilling operations for branch wells. During drilling, an operator first needs to hang the entire whipstock 100 to the wellhead via the support rods, install the milling cone 20 on the lead screw 10, and install the radiation source 64 in the recess 66. The whipstock 100 for sidetracking is then lowered to a predetermined depth downhole with the drill string 21, and is then compressed into the drill string 21, allowing the anchor assembly 30 to complete the pack and hanger. The compression is then continued until the seal 28 fails, and the drill string 21 is depressurized.

After the drill string 21 is depressurized, the drill string 21 is lifted to shear the suspension pin 21, and then the drill string 21 is lowered. The milling cone 20 will now move along the lead-in slope 12 on the lead-in slope 10, changing from a vertical state to an inclined state. At this time, the milling cone 20 can perform oblique hole opening under the driving of the drill string 21, so as to complete the pre-windowing operation.

When the pre-windowing operation is completed, the operator can lift the milling cone 20 up to the wellhead, then lower the drilling tool and position the drilling tool through the positioning assembly 60, so as to perform the inclined drilling operation. After the slant drilling operation and the corresponding well cementation operation are completed, the drilling tool can be lifted up and the perforating gun 121 can be put into the well to perform perforation operation, so that the communication between the vertical well bore and the branch well bore 15 is realized. Finally, a production pipe which is simultaneously communicated with the vertical well and the branch well 151 is put into the shaft, and the production pipe is used for controlling, so that the combined production or the separate production of the vertical well and the branch well 151 is carried out.

Finally, it should be noted that the above description is only of a preferred embodiment of the utility model and is not to be construed as limiting the utility model in any way. Although the utility model has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the techniques described in the foregoing examples, or equivalents may be substituted for elements thereof. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model should be included in the protection scope of the present utility model.

Claims

1. A whipstock (100) for sidetracking a well, comprising:

a bevel gear (10) connected to the drill string, wherein an arc-shaped bevel gear (12) is formed at the upper part of the bevel gear in the axial direction;

a milling cone (20) arranged at the upper end of the bevel guide, the milling cone being movable along the bevel relative to the bevel guide so as to be capable of being converted from a vertical state to an inclined state for forming a branch wellbore,

wherein a central tube body (14) which can be closed by the guide inclined plane is arranged in the guide inclined plane, the lower end of the central tube body is provided with a liquid inlet (141) communicated with the vertical well bore,

the lead-in chamfer is made of a perforating material penetrable by a perforating gun (121) such that the lead-in chamfer can form a channel (152) communicating with the branch wellbore, and the upper end of the central tube body is arranged to extend to the lead-in chamfer.

2. The whipstock for sidetracking as claimed in claim 1, further comprising an anchor assembly (30) provided at the lower end of the lead for separating the wellbore, the anchor assembly comprising a packer (40) and a pressure transfer line (50) communicating the packer with the drill string.

3. Whipstock for sidetracking as claimed in claim 2, wherein a through hole (41) is provided in the packing sleeve allowing the central tube to pass through, a closed annular gap (45) is formed between the central tube and the packing sleeve, a piston (452) is provided in the annular gap which is movable under pressure,

a slip (42) and a sealing rubber cylinder (44) are respectively arranged on the outer wall of the packing cylinder, and the slip and the sealing rubber cylinder can be radially opened under the pushing of a piston.

4. A whipstock for sidetracking as claimed in claim 3, wherein a cavity (26) is provided in the milling cone, the cavity communicating at an upper end with a drill string and at a lower end with the pressure transfer line,

a seal (28) is provided in the cavity separating the cavity from the space outside the milling cone, the seal being provided as a rupture disc which is rupturable under pressure.

5. A whipstock for sidetracking as claimed in any one of claims 1 to 4 further comprising a locating assembly (60) comprising a radiation source (64) disposed on the deflector and a signal receiver connectable to the drill string.

6. Whipstock for sidetracking as claimed in claim 5, wherein a recess (66) is provided in the outer wall of the whipstock, the radiation source being provided in the recess, and a plug (68) closing the recess is provided in the recess.

7. The whipstock for sidetracking as claimed in claim 6, wherein the grooves are provided in two, which are provided on the outer walls of the upper and lower sides of the guide body, respectively.

8. Whipstock for sidetracking as claimed in any of claims 2-4, wherein a through slot (19) is provided in the outer wall of the ramp extending axially through the ramp, the pressure transfer line being provided in the through slot, an elongate baffle closing the through slot being further provided on the through slot,

the through groove is arranged on one side, far away from the guide inclined plane, of the guide inclined plane.

9. Whipstock for sidetracking as claimed in claim 3 or 4, wherein the slips comprise anti-drop slips (422) and anti-rotation slips (424) having respectively elongate and diamond-shaped slip teeth disposed thereon.

10. Whipstock for sidetracking as claimed in any one of claims 1 to 4, wherein a support rod mounting hole (18) is provided radially through the whipstock on the outer wall of the axially upper portion of the whipstock.

11. Whipstock for sidetracking as claimed in any of claims 1 to 4, characterised in that the deflector is connected to the milling cone by a shearable suspension pin (22).