Well cementation multipurpose rubber plug and tool and method for well cementation

Abstract

The invention discloses a multipurpose rubber plug for well cementation and a tool and method for well cementation. The multi-purpose rubber plug for well cementation comprises a rubber plug body, a rubber plug rubber body, an impact sleeve, a pin, a rupture disk and a gland, the rubber plug body is sleeved with the rubber plug rubber body; one end of the pin is inserted into the side wall of the impact sleeve, and the other end of the pin is inserted into the rubber plug body; the side wall of the impact sleeve is connected with the rubber plug body through a pin; the rubber plug body is cylindrical, and an impact sleeve and a rupture disk are arranged in an inner cavity of the rubber plug body from top to bottom; and the gland is in threaded connection with the rubber plug body. The calibration rubber plug can be used in multiple stages of well cementation, can be used as a calibration rubber plug, can improve the metering accuracy of the slurry replacement amount, avoids the problems of casing pipe plug reserving and empty replacement, can provide a corresponding solution for pipe string bouncing and blocking caused by release of the upper rubber plug before cement injection, and avoids well cementation operation accidents.

Description

Technical Field

[0001] The invention relates to the technical field of underground oil and natural gas energy exploration, and in particular to a multi-purpose cementing rubber plug and a cementing tool and method. Background Art

[0002] During the drilling process, in order to reinforce the well wall, ensure continued drilling, seal the oil, gas and water layers, ensure oil testing during exploration and reasonable oil and gas production during the entire mining process, the operation of lowering casing and filling cement in the wellbore and steel pipe annulus is called cementing operation.

[0003] Cementing is an indispensable part of the drilling and completion process, which includes casing and cementing. Cementing technology is a multidisciplinary comprehensive application technology with the characteristics of systematic, one-time and short time. The main purpose of cementing is to protect and support the casing in the oil and gas well, and to isolate the oil, gas and water formations.

[0004] Cementing plugs can be used to isolate cement slurry, clean casing walls, and prevent cement slurry contamination. After the plug collides with the float collar, it can accurately indicate the cement slurry replacement position and casing sealing performance.

[0005] The upper rubber plug and the lower rubber plug are generally used as a set. The upper rubber plug separates the upper cement slurry from the mud to prevent the cement slurry from being contaminated, and at the same time replaces the cement slurry to the annulus.

[0006] Before cementing, first put in the lower rubber plug, pump and scrape the well wall to clean it, which is used to separate the lower cement slurry and mud to prevent the cement slurry from being contaminated. After the collision and pressure, since the lower rubber plug is hollow, the pressure is held and the rubber membrane is broken, providing a channel for the cement slurry to establish circulation. Then, cement is injected, the upper rubber plug is put in, pumping and collision and pressure are applied, and cementing is completed.

[0007] During cementing operations in deep and ultra-deep wells, a large amount of displacement fluid is required. Due to the problem of metering accuracy, people dare not pursue impact pressure during cementing, which causes problems such as casing blockage and emptying, affecting the cementing quality.

[0008] At the same time, when using traditional single-plug cementing operations, when only the cementing upper plug is used, operators may make mistakes and release the upper plug in advance before cementing, causing pipe string blockage and making cementing operations impossible. Summary of the invention

[0009] In view of the above problems, the present invention is proposed to provide a multi-purpose cementing plug and a cementing tool and method that overcome the above problems or at least partially solve the above problems.

[0010] In a first aspect, an embodiment of the present invention provides a multi-purpose rubber plug for cementing, comprising: a rubber plug body, a rubber plug rubber body, an impact sleeve, a pin, a rupture disk and a gland;

[0011] The rubber body of the rubber plug is sleeved outside the rubber plug body;

[0012] One end of the pin is inserted into the side wall of the impact sleeve, and the other end is inserted into the rubber plug body; the side wall of the impact sleeve is connected to the rubber plug body through the pin;

[0013] The rubber plug body is cylindrical, and an impact sleeve and a rupture disk are arranged in its inner cavity from top to bottom;

[0014] The gland is threadedly connected to the rubber plug body.

[0015] In one embodiment, an impact head is provided at one end of the impact sleeve facing the rupture disk, and the impact head is used to impact the edge of the rupture disk when the impact sleeve moves downward under pressure.

[0016] In one embodiment, when the multi-purpose cementing plug is used as a single plug and is used as an upper plug, the pressure level of the pin is set to be one times the cementing construction pressure.

[0017] In one embodiment, when the multi-purpose cementing plug is used as a double plug for construction and as a lower plug, the pressure level of the pin is set to one times the cementing construction pressure;

[0018] When the multi-purpose cementing plug is used as a double plug in construction and as an upper plug, the pressure of the pin meets the downhole plug rupture pressure requirement.

[0019] In one embodiment, when the multi-purpose cementing plug is used as a calibration plug, the pressure level of the pin meets the need for pressure observation.

[0020] In one embodiment, the above-mentioned multi-purpose rubber plug for cementing further includes: a rubber pad;

[0021] The rubber pad is annular and is arranged between the rupture disk and the gland.

[0022] In one embodiment, the multi-purpose rubber plug for cementing further includes: a plurality of sealing rings;

[0023] The plurality of sealing rings are arranged on the side wall of the rubber plug body in sequence from top to bottom, respectively, at the position where the impact sleeve is located and the position where the rupture disk is located.

[0024] In a second aspect, an embodiment of the present invention provides a cementing tool, characterized in that the cementing tool comprises at least one multi-purpose cementing plug as described above.

[0025] In one embodiment, the cementing multipurpose rubber plug is one, which is the upper rubber plug of the cementing tool;

[0026] There are two multi-purpose rubber plugs for cementing, one of which is an upper rubber plug of the cementing tool, and the other is a lower rubber plug of the cementing tool.

[0027] In a third aspect, an embodiment of the present invention provides a method for using the multi-cementing multi-purpose rubber plug as described above, comprising:

[0028] During the cementing operation, the multi-purpose cementing rubber plug is used as an upper rubber plug;

[0029] Alternatively, during the cementing operation, the multi-purpose rubber plug for cementing is first pumped as a lower rubber plug to scrape and clean the well wall, and after cementing, an upper rubber plug is placed, and then pumped and pressed to complete the cementing.

[0030] Or it can be used as a calibration plug during cementing operations.

[0031] The beneficial effects of the above technical solution provided by the embodiment of the present invention include at least:

[0032] The embodiment of the present invention provides a multi-purpose rubber plug for cementing and a tool and method for cementing. The multi-purpose rubber plug for cementing includes a rubber plug body, a rubber plug rubber body, an impact sleeve, a pin, a rupture disk and a pressure cap; one end of the pin is inserted into the side wall of the impact sleeve, and the other end is inserted into the rubber plug body; the side wall of the impact sleeve is connected to the rubber plug body through the pin; the rubber plug body is cylindrical, and the impact sleeve and the rupture disk are arranged in its inner cavity from top to bottom; the pressure cap is threadedly connected to the rubber plug body. The multi-purpose rubber plug for cementing provided by the embodiment of the present invention can be used in multiple stages of cementing operations to improve the quality of cementing operations. The multi-purpose rubber plug for cementing can be used as an upper rubber plug in the cementing process, or used as an upper rubber plug and a lower rubber plug in the cementing process at the same time, and can also be used as a calibration rubber plug in the construction process of calibrating the displacement amount before cementing, which improves the accuracy of the measurement of the displacement amount and solves the problem of casing plugging and emptying caused by the measurement problem in the cementing operation of deep wells and ultra-deep wells in the prior art. It can also provide corresponding solutions when accidents occur in cementing, and release the rubber plug in advance before cementing to prevent pipe string blockage, thus avoiding cementing operation accidents.

[0033] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings.

[0034] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0036] Figure 1 This is a schematic diagram of the structure of a multi-purpose rubber plug for cementing in an embodiment of the present invention;

[0037] Figure 2 It is a schematic diagram of the state in which the impact head of the multi-purpose rubber plug for cementing hits the rupture disk in an embodiment of the present invention;

[0038] Figure 3 This is a schematic diagram of the state after the rupture disk in the multi-purpose rubber plug for cementing in the embodiment of the present invention is ruptured;

[0039] Description of reference numerals:

[0040] 1- gland 2- plug body 3- rubber pad 4- sealing ring 5- rupture disk

[0041] 6-seal ring 7-impact sleeve 8-seal ring 9-nail 10-rubber plug rubber body

[0042] 11- Head impact. DETAILED DESCRIPTION

[0043] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0044] The embodiment of the present invention provides a multi-purpose cementing rubber plug, the structure of which can refer to Figure 1 As shown, the rubber plug comprises: a rubber plug body 2, a rubber plug rubber body 10, an impact sleeve 7, a pin 9, a rupture disk 5 and a gland 1; wherein:

[0045] The rubber body 10 of the rubber plug is sleeved on the outside of the rubber plug body 2;

[0046] One end of the pin 9 is inserted into the side wall of the impact sleeve 7, and the other end is inserted into the rubber plug body 2; the side wall of the impact sleeve 7 is connected to the rubber plug body 10 through the pin 9;

[0047] The rubber plug body 10 is cylindrical, and an impact sleeve 7 and a rupture disk 5 are arranged in its inner cavity from top to bottom;

[0048] The gland 1 is threadedly connected to the rubber plug body 2 .

[0049] The plug body 2 and the plug rubber body 10 are integrated by vulcanization. The plug rubber body 10 has a tooth-like shape, which plays a role in scraping and cleaning the well wall during the cementing process.

[0050] In the above multi-purpose rubber plug for cementing, an impact head 11 is provided at one end of the impact sleeve 7 facing the rupture disk 5. The impact head 11 is used to impact the edge of the rupture disk 5 when the impact sleeve 7 moves downward under pressure.

[0051] The rupture disk is made of easily breakable material, so that when the multi-purpose cementing plug is pumped to the bottom of the well, the pump pressure will increase instantly. Under the action of pressure, the shear pin 9 will instantly move downward and the impact head 11 will hit the edge of the rupture disk 5, causing the rupture disk 5 to rupture.

[0052] In one embodiment, referring to Figure 1 As shown, the above-mentioned multi-purpose rubber plug for cementing further includes: a rubber pad 3;

[0053] The rubber pad 3 is annular and is arranged between the rupture disk 5 and the gland 1 .

[0054] When the impact head 11 impacts the rupture disk 5 , the rubber pad 3 can buffer the pressure on the gland 1 below, so as to reduce the impact force on the gland 1 below the rupture disk 5 when the rupture disk 5 ruptures.

[0055] In one embodiment, referring to Figure 1 As shown, the above multi-purpose cementing rubber plug also includes: a plurality of sealing rings 4; wherein:

[0056] A plurality of sealing rings 4 are arranged on the side wall of the rubber plug body 2 in sequence from top to bottom, respectively, at the position where the impact sleeve 7 is located and the position where the rupture disk 5 is located.

[0057] Reference Figure 1 In the example shown, the multi-purpose cementing plug includes three sealing rings from top to bottom, wherein the sealing ring 8 and the sealing ring 6 are both arranged on the outside of the impact sleeve 7 to ensure that the plug body 2 and the impact sleeve 7 still maintain good sealing when the impact sleeve 7 moves downward to impact the rupture disk 5.

[0058] The sealing ring 4 is arranged on the outside of the rupture disk 5 , and also plays a role in maintaining good sealing of the rubber plug body 2 .

[0059] by Figure 1 Taking the structure shown in the figure as an example, the assembly process of the multi-purpose rubber plug for cementing provided in the embodiment of the present invention is as follows:

[0060] The main body 2 and the rubber body 10 of the rubber plug are integrated by vulcanization; then the sealing ring 4, sealing ring 6 and sealing ring 8 are installed into the main body 2, and then the rupture disk 5 is installed into the main body 2 and the rubber pad 3 is installed, and the pressure cover 1 is threadedly connected with the main body 2 and tightened; the impact sleeve 7 is installed from the upper end, and the pin 9 is screwed on.

[0061] The multi-purpose rubber plug for cementing provided in the embodiment of the present invention can be applied to a variety of scenarios. One is to be used as a double rubber plug during cementing, i.e., an upper rubber plug and a lower rubber plug.

[0062] The other is used as a single rubber plug during cementing, i.e., upper rubber plug.

[0063] Another type is used as a calibration plug during the fixing operation.

[0064] Another situation is that during cementing operations, if the operator makes a mistake and releases the multi-purpose cementing plug used as the upper plug in advance before cementing, causing the pipe string to be blocked, a channel is provided for the mud to establish circulation and then cementing is carried out according to normal procedures.

[0065] In the above-mentioned cases, when the multi-purpose rubber plug for cementing is used as a double rubber plug for construction and as a lower rubber plug, the pressure level of the pin is set to one times the cementing construction pressure;

[0066] When the multi-purpose cementing plug is used as a double plug in construction and as an upper plug, the pressure of the pin meets the downhole plug rupture pressure requirement.

[0067] When the multi-purpose cementing plug is used as a calibration plug, the pressure level of the pin meets the need for pressure observation.

[0068] Based on this, when the multi-purpose cementing plug is used in different scenarios, the nail 9 needs to be replaced according to the actual scenario to meet the pressure requirements in different scenarios.

[0069] Specifically, when the multi-purpose cementing plug is used as a double plug in cementing operations, one of the multi-purpose cementing plugs is used as a lower plug, and the pin 9 on the impact sleeve 7 is replaced at this time to make its pressure meet the requirements of the fracture pressure of the lower cementing plug. Then the other multi-purpose cementing plug is used as an upper plug, and at this time, the pin on the impact sleeve needs to be replaced to make its pressure meet the requirements of the cementing of the upper plug, and the pressure level of the pin 9 on the impact sleeve 7 is set to one times the cementing construction pressure.

[0070] During the cementing operation, the lower rubber plug is first placed before cementing, and the well wall is cleaned by pumping and scraping to separate the lower cement slurry from the mud to prevent the cement slurry from being contaminated. After the collision and pressure, the impact sleeve 7 in the multi-purpose rubber plug for cementing provided by the embodiment of the present invention shears off the pin 9 under the action of pressure, and the impact head 11 instantly descends and hits the edge of the rupture disk 5, causing the rupture disk 5 to rupture, providing a channel for the cement slurry and establishing circulation. Then, the displacement continues, and the multi-purpose rubber plug for cementing used as the upper rubber plug is pumped to the collision and pressure position at the bottom of the well, and the collision and pressure are completed, and the cementing is completed.

[0071] During the cementing operation, when the multi-purpose rubber plug for cementing provided in the embodiment of the present invention is used as a single rubber plug, the multi-purpose rubber plug for cementing is used as an upper rubber plug. At this time, the pin 9 on the impact sleeve is replaced so that its pressure meets the cementing requirements of the upper rubber plug for cementing. The pressure level of the pin 9 on the impact sleeve 7 is set to one times the cementing construction pressure to meet the pressure requirements of single rubber plug cementing. After the cementing step in the cementing operation process, the multi-purpose rubber plug for cementing used as the upper rubber plug is put in, and the well wall is cleaned by pumping and scraping to separate the lower cement slurry and mud to prevent the cement slurry from being contaminated. Pump to the bottom of the well to the impact pressure position, impact pressure, and cementing is completed.

[0072] During cementing operations, the multi-purpose cementing plug provided in the embodiment of the present invention is used as a calibration plug; when the multi-purpose cementing plug is used as a calibration plug, the pin 9 on the impact sleeve is replaced so that its pressure level meets the needs of pressure observation. When the multi-purpose cementing plug is pumped to the bottom of the well, the pump pressure will increase instantly. Under the action of pressure, the pin 9 is cut off and the impact head 11 instantly descends and hits the edge of the rupture disk 5. The rupture disk 5 ruptures, providing a channel for cement slurry and establishing circulation. The injection displacement when the pressure rises is compared with the calculated volume to calibrate the displacement.

[0073] During cementing operations, if the operator makes a mistake and releases the multi-purpose cementing plug used as the upper plug in advance before cementing, the pipe string will be blocked. When the multi-purpose cementing plug is continued to be pumped to the bottom of the well, the pump pressure will increase instantly and the pressure will reach the set pressure. Under the action of pressure, the shear pin 9 will instantly move downward and the impact head 11 will hit the edge of the rupture disk 5, causing the rupture disk 5 to rupture, providing a channel for the mud. After the circulation is established, cementing is carried out according to the normal procedure.

[0074] Reference Figure 1-Figure 3 As shown, Figure 1 In the figure, the positional relationship among the cementing multi-purpose rubber plug impact sleeve 7, the impact head 11 and the rupture disk 5 is that the impact head 11 is located above the rupture disk 5 and has a certain distance from the rupture disk 5. Figure 2 The figure shows the state where the impact head 11 impacts the edge of the rupture disk 5 under pressure; Figure 3 The figure shows the state after the impact head 11 impacts the edge of the rupture disk 5, causing the rupture disk 5 to rupture. Figure 1-Figure 3It can be seen that the impact head 11 contacts the rubber pad 3, and the rupture disk 5 has been ruptured, forming a channel for the cement slurry and establishing circulation.

[0075] Based on the same inventive concept, an embodiment of the present invention further provides a cementing tool and a method of using a multi-cementing multi-purpose rubber plug.

[0076] A cementing tool provided in an embodiment of the present invention comprises the multi-purpose cementing rubber plug provided in an embodiment of the present invention;

[0077] In cementing tools, cementing plugs are usually used in conjunction with spoilers or floating collars to achieve collision pressure.

[0078] In double-plug cementing, when the upper plug hits the lower plug, or in single-plug cementing when the upper plug hits the baffle, the pressure will suddenly increase. This moment is the collision pressure.

[0079] In one embodiment, in the above-mentioned cementing tool, there is one multi-purpose cementing plug, which is the upper plug of the cementing tool;

[0080] There are two multi-purpose rubber plugs for cementing, one of which is an upper rubber plug of the cementing tool, and the other is a lower rubber plug of the cementing tool.

[0081] The method for using the multi-cementing multi-purpose rubber plug as described above provided in an embodiment of the present invention comprises:

[0082] During the cementing operation, the multi-purpose cementing rubber plug is used as an upper rubber plug;

[0083] Alternatively, during the cementing operation, the multi-purpose rubber plug for cementing is first pumped as a lower rubber plug to scrape and clean the well wall, and after cementing, an upper rubber plug is placed, and then pumped and pressed to complete the cementing.

[0084] Or it can be used as a calibration plug during cementing operations.

[0085] The multi-purpose rubber plug for cementing and the tool and method for cementing provided in the embodiment of the present invention include a rubber plug body, a rubber plug rubber body, an impact sleeve, a pin, a rupture disk and a gland; one end of the pin is inserted into the side wall of the impact sleeve, and the other end is inserted into the rubber plug body; the side wall of the impact sleeve is connected to the rubber plug body through the pin; the rubber plug body is cylindrical, and the impact sleeve and the rupture disk are arranged in its inner cavity from top to bottom; the gland is threadedly connected to the rubber plug body. The multi-purpose rubber plug for cementing provided in the embodiment of the present invention can be used in multiple stages of cementing operations to improve the quality of cementing operations. The multi-purpose rubber plug for cementing can be used as an upper rubber plug in the cementing process, or as an upper rubber plug and a lower rubber plug in the cementing process at the same time, and can also be used as a calibration rubber plug in the construction process of calibrating the displacement amount before cementing, which improves the accuracy of the measurement of the displacement amount and solves the problem of casing plugging and emptying caused by the measurement problem in the cementing operation of deep wells and ultra-deep wells in the prior art. It can also provide corresponding solutions when accidents occur during cementing and the upper rubber plug is released in advance before cementing, causing pipe string blockage, thus avoiding cementing operation accidents.

[0086] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A multi-purpose rubber plug for cementing, characterized in that: include: Plug body, plug rubber body, impact sleeve, pin, rupture disc and gland; The rubber body of the rubber plug is sleeved outside the rubber plug body; One end of the pin is inserted into the side wall of the impact sleeve, and the other end is inserted into the rubber plug body; the side wall of the impact sleeve is connected to the rubber plug body through the pin; The rubber plug body is cylindrical, and an impact sleeve and a rupture disk are arranged in its inner cavity from top to bottom; The gland is threadedly connected to the rubber plug body.

2. The multi-purpose rubber plug for cementing as claimed in claim 1, characterized in that: An impact head is arranged at one end of the impact sleeve facing the rupture disk, and the impact head is used to impact the edge of the rupture disk when the impact sleeve moves downward under pressure.

3. The multi-purpose rubber plug for cementing as claimed in claim 1, characterized in that: When the multi-purpose cementing plug is used as a single plug for construction and as an upper plug, the pressure level of the pin is set to be one times the cementing construction pressure.

4. The multi-purpose rubber plug for cementing as claimed in claim 1, characterized in that: When the multi-purpose rubber plug for cementing is used as a double rubber plug for construction and as a lower rubber plug, the pressure level of the pin is set to be one times the cementing construction pressure; When the multi-purpose cementing plug is used as a double plug in construction and as an upper plug, the pressure of the pin meets the downhole plug rupture pressure requirement.

5. The multi-purpose rubber plug for cementing as claimed in claim 1, characterized in that: When the multi-purpose cementing plug is used as a calibration plug, the pressure level of the pin meets the need for pressure observation.

6. The multi-purpose rubber plug for cementing as claimed in any one of claims 1 to 5, characterized in that: Also includes: Rubber pads; The rubber pad is annular and is arranged between the rupture disk and the gland.

7. The multi-purpose rubber plug for cementing as claimed in any one of claims 1 to 5, characterized in that: Also includes: Multiple sealing rings; The plurality of sealing rings are arranged on the side wall of the rubber plug body in sequence from top to bottom, respectively, at the position where the impact sleeve is located and the position where the rupture disk is located.

8. A cementing tool, characterized in that: The cementing tool comprises at least one multi-purpose cementing plug as described in any one of claims 1-7.

9. The cementing tool according to claim 8, characterized in that: The multi-purpose rubber plug for cementing is one, which is the upper rubber plug of the cementing tool; There are two multi-purpose rubber plugs for cementing, one of which is an upper rubber plug of the cementing tool, and the other is a lower rubber plug of the cementing tool.

10. A method for using the multi-cementing multi-purpose rubber plug according to any one of claims 1 to 7, characterized in that: include: During the cementing operation, the multi-purpose cementing rubber plug is used as an upper rubber plug; Alternatively, during the cementing operation, the multi-purpose rubber plug for cementing is first pumped as a lower rubber plug to scrape and clean the well wall, and after cementing, an upper rubber plug is placed, and then pumped and pressed to complete the cementing. Or it can be used as a calibration plug during cementing operations.

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