Integrated Drilling Collapse Prevention and Sand Removal Device

Abstract

This utility model provides an integrated device for preventing and removing sand while drilling, including an intermediate pipe and an anti-collapse component. The anti-collapse component includes a straight connecting sleeve that is sleeved outside the intermediate pipe and abuts against the horizontal plane of the well wall, and a pusher plate disposed at the top of the straight connecting sleeve. A drill bit is provided at the bottom end of the intermediate pipe, and the distance between the pusher plate and the drill bit is greater than the length of the straight connecting sleeve.

Description

Technical Field

[0001] This utility model relates to the field of oil and gas field drilling, specifically to an integrated device for preventing collapse and removing sand while drilling. Background Technology

[0002] Currently, the main producing layers of the Tarim Oilfield are located in the Ordovician system. Due to the development of mudstone in the Upper Ordovician, there are some risks during production and well workover. First, there is an error between the predicted well depth and the actual drilling depth. Second, there is a risk of leakage and drill bit burial during drilling. To avoid these risks, cementing operations are performed when the predicted depth is reached. This error directly results in a relatively long exposed length of the Upper Ordovician layer in most wells, especially in horizontal and deviated wells, where this problem is particularly prominent.

[0003] However, during production, the mudstone's susceptibility to hydration and unstable properties pose a significant risk of wellbore collapse. During well workover, the mudstone section is at high risk of repeated collapses, resulting in a large workload for wellbore repair and significantly increasing the difficulty and risk of the workover process.

[0004] Therefore, it is desirable in this field to provide an integrated device for preventing and removing sand during drilling to solve the above-mentioned technical problems. Utility Model Content

[0005] The purpose of this utility model is to propose an integrated device for preventing ground collapse and dredging sand while drilling, which can effectively avoid accidents such as drill bit burial caused by ground collapse.

[0006] According to this utility model, an integrated device for preventing drilling collapse and dredging is provided, including an intermediate pipe, and... The anti-collapse assembly includes a straight-connecting casing sleeved outside the intermediate pipe and abutting against the horizontal plane of the well wall, and a pusher plate disposed at the top of the straight-connecting casing. A drill bit is provided at the bottom end of the intermediate tube, and the distance between the pusher and the drill bit is greater than the length of the direct-connecting sleeve.

[0007] In one embodiment, the outer diameter of the pusher is not greater than the outer diameter of the straight-connected casing, and the straight-connected casing can move synchronously downwards under the action of the pusher when the drill bit moves downwards.

[0008] In one embodiment, the drilling range of the drill bit on the horizontal plane inside the well is greater than the outer diameter of the straight-connected casing.

[0009] In one embodiment, the straight-connecting casing is concentrically arranged inside the well, and the outer diameter of the straight-connecting casing is smaller than the diameter of the well wall.

[0010] In one embodiment, an annular channel is formed between the intermediate pipe and the well wall to allow the passage of viscosity-enhancing and kill fluid.

[0011] In one embodiment, the density of the viscosity-enhancing and kill fluid is 1.0-1.25 g / cm³.

[0012] In one embodiment, a plurality of circumferentially spaced channels are provided at the junction of the intermediate tube and the drill bit, allowing a mixture of viscosity-enhancing and kill fluid and cuttings to enter.

[0013] In one embodiment, the integrated drilling anti-collapse and sand-removal device further includes a sand-sinking pipe sleeved outside the intermediate pipe and located above the pusher plate, wherein the intermediate pipe is hollow and communicates with the sand-sinking pipe.

[0014] In one embodiment, the sand-absorbing pipe includes a first channel and a second channel separated by an annular baffle, the first channel being in communication with the intermediate pipe, thereby allowing a mixture of viscosity-enhancing and kill fluid and cuttings to sequentially pass through the intermediate pipe and the first channel into the second channel.

[0015] In one embodiment, a gap is left between the sand settling pipe and the pusher plate.

[0016] Compared with the prior art, the advantages of this utility model are: Firstly, this invention can effectively prevent accidents such as drill bit burial caused by formation collapse. This device is suitable for wells with large leakage and inability to establish circulation. Furthermore, through the cooperation of the pusher and drill bit, the straight-connected casing serves as a support tailpipe. The straight-connected casing utilizes its large diameter and resistance to external extrusion to meet the needs of later production while reducing the risk of formation collapse in the later stages.

[0017] During downhole drilling, the drill bit always performs the initial treatment work first, followed by the direct-connect casing entering the treated formation area and contacting the wellbore wall. This provides effective support and reduces the risk of formation collapse later. Furthermore, during formation treatment, the pusher plate 22, direct-connect casing, and drill bit are drilled simultaneously, effectively preventing accidents such as drill bit burial caused by formation collapse.

[0018] Secondly, this invention solves the problem of drill cuttings not being carried out of the wellhead. Specifically, this device employs a reverse circulation sand removal process, utilizing an externally mounted high-capacity pump truck in conjunction with a sand settling pipe to achieve reverse circulation and resolve the issue of drill cuttings not being carried out of the wellhead. Furthermore, the viscosity-enhancing kill fluid in this invention has a high viscosity, thus possessing a stronger sand-carrying capacity. During reverse circulation, it enables more efficient return of rock cuttings generated during the process to the sand settling pipe for subsequent recovery. Simultaneously, the density of the viscosity-enhancing kill fluid also provides some support to the wellbore, further improving the stability of the wellbore in the mudstone section.

[0019] Thirdly, this device can process long naked-eye segments, avoiding accidents during the processing of long naked-eye segments. Attached Figure Description

[0020] The present invention will now be described in detail with reference to the accompanying drawings, in which: Figure 1 The schematic diagram shows the structure of the integrated drilling anti-collapse and sand-removal device according to the present invention.

[0021] In the accompanying drawings, the same parts use the same reference numerals. The drawings are not drawn to scale. Detailed Implementation

[0022] To make the technical solution and advantages of this utility model clearer, the exemplary embodiments of this utility model will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not an exhaustive list of all embodiments. Furthermore, without conflict, the embodiments and features in the embodiments of this utility model can be combined with each other.

[0023] Currently, the main producing layers in the Tarim Oilfield are located in the Ordovician system. Most wells have long exposed sections in the Upper Ordovician, consisting of mudstone, a problem particularly prominent in horizontal and deviated wells. With continuous oil production, the risk of wellbore collapse is extremely high. For wells with large leakage rates, inability to circulate normally, and long collapsed sections, existing processes cannot meet the requirements for preventing mudstone collapse and ensuring operational safety during wellbore treatment. To solve these technical problems, the inventors have provided an integrated drilling anti-collapse and sand-removal device 100. The following will further describe this utility model with reference to the accompanying drawings.

[0024] Figure 1 The schematic diagram shows the structure of the integrated drilling anti-collapse and sand-removal device 100 according to the present invention.

[0025] like Figure 1As shown, the integrated anti-collapse and sand-removal device 100 according to this utility model mainly includes an intermediate pipe 10 and an anti-collapse component disposed on the intermediate pipe 10. Preferably, the anti-collapse component includes a straight connecting sleeve 21 sleeved outside the intermediate pipe 10 and a pusher 22 disposed at the top of the straight connecting sleeve 21, wherein the lower end face of the straight connecting sleeve 21 will directly abut against the horizontal surface of the well wall after it is lowered.

[0026] In this utility model, such as Figure 1 As shown, a drill bit 12 is also provided at the bottom end of the intermediate pipe 10. Therefore, during downhole operations, the drill bit 12 can complete the drilling work inside the well, while the direct-connecting casing 21 can achieve synchronous axial displacement with the drill bit 12 under the action of the pusher 22. In other words, while the drill bit 12 can perform treatment work on the lower formation, the direct-connecting casing 21 can advance and enter the formation area that has been treated under its own weight and the combined action of the pusher 22 to make contact with the well wall, thereby playing an effective supporting role inside the well and further achieving the purpose of meeting the needs of later production and reducing the risk of later formation collapse.

[0027] In one embodiment of this invention, the distance between the pusher plate 22 and the drill bit 12 is greater than the length of the direct-connecting casing 21. That is, the drill bit can extend beyond the direct-connecting casing 21 to process the underlying formation. Therefore, during downhole drilling, the drill bit 12 always performs the processing work first, and then the direct-connecting casing 21 enters the processed formation area and abuts against the well wall, thus providing effective support and reducing the risk of subsequent formation collapse. Both continue to advance and process until the target point is reached to meet geological requirements.

[0028] In one embodiment, the outer diameter of the pusher 22 is no greater than the outer diameter of the direct-connected casing 21, and the pusher 22 can be connected to an external control module via a cable, thereby allowing the direct-connected casing 21 to be pushed downwards actively. Preferably, when performing vertical processing work in the well, the direct-connected casing 21 can be pushed downwards synchronously with the drill bit 12 by its own weight, or the pusher 22 can be used to push the direct-connected casing 21 downwards synchronously with the drill bit 12.

[0029] In this invention, the drilling range of the drill bit 12 on the horizontal plane inside the well is greater than the outer diameter of the direct-connecting casing 21. That is, the downhole space presented by the drill bit 12 after processing the formation should be greater than the outer diameter of the direct-connecting casing 21. In this way, not only can downhole support work be completed more easily through the direct-connecting casing 21 to avoid the risk of formation collapse, but it can also ensure that there is a certain annular cavity between the direct-connecting casing 21 and the well wall, which helps to inject viscosity-enhancing and killing fluid into the annulus to improve the sand-carrying capacity of this device.

[0030] However, in actual well workover processes, the first step is to address the problem of excessive leakage after reaching a single room, which prevents the kill fluid from circulating back and causes the annular cuttings to be lost. To address this issue, this application proposes the following structure.

[0031] In one embodiment, the direct-connecting casing 21 is concentrically arranged within the well, and the outer diameter of the direct-connecting casing 21 is smaller than the diameter of the well wall 30. An annular channel 31, allowing viscosity-enhancing and kill fluid to pass through, is formed between the intermediate pipe 10 and the well wall 30. The device also includes a sand-falling pipe 11 sleeved outside the intermediate pipe 10 and positioned above the pusher plate 22. Preferably, the intermediate pipe 10 is hollow and is fully connected to the sand-falling pipe 11.

[0032] This device features a reverse circulation sand removal process and can utilize an externally mounted high-displacement pump truck in conjunction with the sand settling pipe 11 to achieve reverse circulation, thereby solving the problem of drill cuttings not being carried out of the wellhead. In this invention, a viscosity-enhancing and killing fluid is injected into the annulus between the direct-connect casing 21 and the well wall. After the viscosity-enhancing and killing fluid enters the bottom of the well, it carries the drill cuttings into the intermediate pipe 10, and then through the intermediate pipe 10 into the sand settling pipe 11 to temporarily store the returned drill cuttings.

[0033] Preferably, the viscosity-enhancing kill fluid of this invention has a high viscosity, thus enabling it to carry more sand and allowing rock cuttings generated during reverse circulation to be returned more efficiently to the settling pipe 11 for subsequent recovery. Furthermore, the density of the viscosity-enhancing kill fluid also provides some support to the wellbore, further improving the stability of the wellbore in the mudstone section.

[0034] In this invention, the density of the viscosity-enhancing kill fluid is 1.0-1.25 g / cm³, and the viscosity of the viscosity-enhancing kill fluid can be increased to 50±s, thus effectively improving the cuttings carrying capacity.

[0035] In one embodiment, a plurality of through slots (not shown) are provided at the junction of the intermediate pipe 10 and the drill bit 12. Preferably, the plurality of through slots are arranged circumferentially on the intermediate pipe 10, and the through slots enable the mixture of thickening and killing fluid and cuttings in the annulus between the direct-connected casing 21 and the well wall to smoothly enter the intermediate pipe 10 and the sand-removing pipe 11.

[0036] In one embodiment, such as Figure 1 As shown, the sand removal pipe 11 includes a first channel 111 and a second channel 112 separated by an annular baffle 113. Preferably, the first channel 111 is connected to the intermediate pipe 10, thereby allowing a mixture of viscosity-enhancing and killing fluid and cuttings to sequentially enter the second channel 112 through the intermediate pipe 10 and the first channel 111, thereby realizing a reverse circulation sand removal process to effectively solve the problem that drill cuttings cannot be carried out of the wellhead.

[0037] Preferably, a gap is left between the sedimentation pipe 11 and the pusher plate 22, so that the work of recovering rock cuttings through the sedimentation pipe 11 and the work of preventing collapse through the direct connection sleeve 21 can be carried out independently.

[0038] This device is primarily designed for wells with high leakage rates and where circulation cannot be established. By employing reverse circulation sand removal technology combined with anti-scaffolding technology, it efficiently handles cuttings from the bottom of the well in a single drilling run, preventing repeated collapses and reducing the risk of stuck pipe. Furthermore, by using a high-strength, thin-walled, straight-connected casing 21 as the support string, the high-strength, thin-walled casing provides good resistance to external pressure, supports the wellbore, and allows for a larger diameter to accommodate subsequent tool selection. The straight-connected casing 21 also reduces resistance during running and while drilling. Additionally, by adding a suitably sized pusher plate 22 to the drill string assembly, with the distance between it and the drill bit 12 slightly exceeding the length of the straight-connected casing 21, the pusher plate 22 can stably push the straight-connected casing 21 to provide support for the newly treated well section during pressurized drilling. Simultaneously, the distance between the pusher plate 22 and the drill bit 12 ensures a safe distance between the drill bit 12 and the straight-connected casing 21 during drilling, preventing accidents such as drill string entrapment due to wellbore blockage.

[0039] This device enables the treatment of long collapsed sections while ensuring operational safety and preventing accidents caused by further collapse. It can also maintain wellbore cleanliness and treat to the target depth even in the event of loss of return. This significantly reduces the workload of wellbore treatment and greatly lowers the difficulty and risk of well workover, providing a new approach and method for wellbore treatment and restoration in the Tarim Oilfield. It can treat all exposed and easily collapsed well sections within the Tarim Oilfield work area, and this technology has broad prospects for widespread application in wellbore treatment.

[0040] Compared with existing technologies, the advantages of this utility model are: Firstly, this utility model can effectively avoid accidents such as drill bit burial caused by formation collapse. This device is suitable for wells with large leakage and inability to establish circulation. Furthermore, through the cooperation of the pusher plate 22 and the drill bit 12, the straight-connected casing 21 is used as a support tailpipe. The straight-connected casing 21 utilizes its large diameter and high resistance to external extrusion to meet the needs of later production, while reducing the risk of formation collapse in the later stage.

[0041] During downhole drilling, drill bit 12 always performs the initial treatment work first, followed by the direct-connect casing 21 entering the treated formation area and contacting the wellbore wall. This provides effective support and reduces the risk of formation collapse later. Furthermore, during formation treatment, pusher plate 22, direct-connect casing 21, and drill bit 12 drill simultaneously, effectively preventing formation collapse and accidents such as drill bit burial.

[0042] Secondly, this invention solves the problem of drill cuttings not being carried out of the wellhead. Specifically, this device employs a reverse circulation sand removal process, and can utilize an externally mounted high-capacity pump truck in conjunction with the sand settling pipe 11 to achieve reverse circulation, thus resolving the issue of drill cuttings not being carried out of the wellhead. Furthermore, the viscosity-enhancing kill fluid in this invention has a high viscosity, thus possessing a stronger sand-carrying capacity. During reverse circulation, it enables the rock cuttings generated during the process to be returned to the sand settling pipe 11 more efficiently for subsequent recovery. Simultaneously, the density of the viscosity-enhancing kill fluid also provides some support to the wellbore, further improving the stability of the wellbore in the mudstone section.

[0043] Thirdly, this device can process long naked-eye segments, avoiding accidents during the processing of long naked-eye segments.

[0044] In the description of this utility model, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" and "second" may explicitly or implicitly include one or more of that feature.

[0045] In this utility model, unless otherwise explicitly specified and limited, the terms "installation", "connection", "linking", "fixing" and other such terms should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components.

[0046] Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0047] The above are merely preferred embodiments of this utility model, but the protection scope of this utility model is not limited thereto. Those skilled in the art can easily make changes or modifications within the scope of this utility model, and such changes or modifications should be covered within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.

Claims

1. A device for integrated sand bailing and collapse prevention while drilling, characterized in that, include: Intermediate tube (10), and The anti-collapse component includes a straight connecting sleeve (21) sleeved outside the intermediate pipe (10) and abutting against the horizontal plane of the well wall, and a pusher plate (22) disposed at the top of the straight connecting sleeve (21). A drill bit (12) is provided at the bottom end of the intermediate tube (10), and the distance between the pusher (22) and the drill bit (12) is greater than the length of the direct connecting sleeve (21).

2. The sand recovery and hole collapse prevention integrated device while drilling according to claim 1, characterized in that, The outer diameter of the pusher (22) is not greater than the outer diameter of the straight connecting sleeve (21), and the straight connecting sleeve (21) can move down synchronously under the action of the pusher (22) when the drill bit (12) moves down.

3. The integrated sand recovery and hole collapse prevention while drilling device of claim 2, wherein, The drilling range of the drill bit (12) on the horizontal plane inside the well is greater than the outer diameter of the straight casing (21).

4. The integrated drilling anti-collapse and sand-retrieving device according to claim 3, characterized in that, The straight connecting sleeve (21) is concentrically arranged inside the well, and the outer diameter of the straight connecting sleeve (21) is smaller than the diameter of the well wall (30).

5. The integrated sand recovery and hole collapse prevention device while drilling according to claim 4, wherein, An annular channel (31) is formed between the intermediate pipe (10) and the well wall (30) to allow the passage of viscosity-enhancing and pressure-killing fluid.

6. The integrated sand recovery and hole collapse prevention while drilling device of claim 5, wherein, The density of the viscosity-enhancing and kill fluid is 1.0-1.25 g / cm³.

7. The integrated sand recovery and hole collapse prevention while drilling device of claim 6, wherein, At the junction of the intermediate pipe (10) and the drill bit (12), there are multiple circumferentially spaced channels that allow a mixture of viscosity-enhancing and killing fluid and cuttings to enter.

8. The integrated drilling anti-collapse and sand-retrieving device according to claim 7, characterized in that, The integrated drilling anti-collapse and sand-removal device also includes a sand-sinking pipe (11) sleeved outside the intermediate pipe (10) and located above the pusher plate (22). The intermediate pipe (10) is hollow and connected to the sand-sinking pipe (11).

9. The integrated sand recovery and hole collapse prevention while drilling device of claim 8, wherein, The settling pipe (11) includes a first channel (111) and a second channel (112) separated by an annular baffle (113). The first channel (111) is connected to the intermediate pipe (10), thereby allowing a mixture of viscosity-enhancing and killing fluid and cuttings to enter the second channel (112) sequentially through the intermediate pipe (10) and the first channel (111).

10. The integrated sand recovery and hole collapse prevention device according to claim 8 or 9, wherein, There is a gap between the sedimentation pipe (11) and the pusher plate (22).

Images