Fine pressure control well drilling filtering device and well drilling filtering method

Abstract

The invention relates to the field of fine pressure control well drilling, in particular to a fine pressure control well drilling filtering device and a well drilling filtering method, and aims to relieve the technical problem of unstable pressure during fine pressure control well drilling construction in related technologies. By the adoption of the fine pressure control well drilling filtering device, after one filtering channel is blocked, the other filtering channel can be switched, the fine pressure control manifold is prevented from being blocked, in this way, a channel cleaning filter of the fine pressure control manifold does not need to be switched, the fine pressure control well drilling technological process can continue to be carried out, meanwhile, the flowing smoothness of drilling fluid is guaranteed, and the drilling efficiency is improved. The pressure fluctuation is reduced, the construction safety is improved, and the application range of the fine pressure control drilling technology is widened.

Description

Technical Field

[0001] The invention relates to the field of fine pressure controlled drilling, and in particular to a fine pressure controlled drilling filtering device and a drilling filtering method. Background Art

[0002] Fine pressure-controlled drilling technology is a drilling technology used to control the annular pressure of the wellbore. It mainly achieves relatively stable control of the bottom hole pressure by controlling the drilling fluid density, equivalent circulating density and wellhead back pressure.

[0003] During the specific implementation process, due to the continuous occurrence of wellbore instability, a large number of blocks will be ejected, causing the wellhead pressure to fluctuate greatly. In severe cases, the fine pressure control manifold will be blocked, requiring the channel to be switched every 10-20 minutes to clean the filter, and the fine pressure control drilling process will be forced to terminate. In addition, when the wellhead back pressure fluctuates, if the back pressure rises quickly or even becomes blocked, it is easy to cause the channel to be switched untimely and cause well leakage. Excessive pressure fluctuations during pressure control will also cause the downhole breathing effect, causing problems such as wellbore instability and the opening of oil and gas channels, which brings great safety hazards to the construction.

[0004] The above problems seriously restrict the application scope of fine pressure controlled drilling technology. It cannot be effectively applied and promoted in large wellbores, narrow windows or even negative windows, pressure-sensitive formations, and unstable formations with overflows, collapses, etc. Summary of the invention

[0005] The object of the present invention is to provide a fine pressure controlled drilling filtration device and a drilling filtration method to alleviate the technical problem of unstable pressure during fine pressure controlled drilling construction in the related art.

[0006] In order to solve the above technical problems, the technical solution provided by the present invention is:

[0007] In a first aspect, the present invention provides a fine pressure controlled drilling filter device, comprising: a fine pressure controlled manifold, a main filter assembly, a spare filter assembly and a control assembly;

[0008] The main filter assembly has a main filter channel for circulating drilling fluid to filter the drilling fluid, and the inlet and outlet of the main filter channel are respectively connected to the annulus and the fine pressure control manifold;

[0009] The standby filter assembly has a standby filter channel for circulating drilling fluid to filter the drilling fluid, and the inlet and outlet of the standby filter channel are also connected to the annulus and the fine pressure control manifold respectively;

[0010] The control assembly is respectively connected to the main filter assembly and the backup filter assembly for controlling the opening and closing of the main filter channel and the backup filter channel respectively. The control assembly is configured to open the main filter channel and the backup filter channel when one of the main filter channel and the backup filter channel is blocked, and then close the blocked one.

[0011] Further, the main filter assembly includes a first sand removal box and a first electric flat valve;

[0012] The first desanding box has a first inlet and a first outlet, the first inlet is connected to the annulus, and the first outlet is connected to the fine pressure control manifold;

[0013] The first electric flat valve is provided with two, one of which is arranged between the first inlet and the annulus, and the other is arranged between the first outlet and the fine pressure control manifold;

[0014] The control assembly is communicatively connected with the first sand removal box and the first electric flat valve respectively.

[0015] Furthermore, the main filter assembly further includes a first pressure sensor, and two first pressure sensors are provided, one of which is arranged between the first inlet and the annulus, and the other is arranged between the first outlet and the fine pressure control manifold;

[0016] The control assembly is communicatively connected to the first pressure sensor.

[0017] Further, the standby filter assembly includes a second sand removal box and a second electric flat valve;

[0018] The second desanding box has a second inlet and a second outlet, the second inlet is connected to the annulus, and the second outlet is connected to the fine pressure control manifold;

[0019] The second electric flat valve is provided with two, one of which is arranged between the second inlet and the annulus, and the other is arranged between the second outlet and the fine pressure control manifold;

[0020] The control assembly is communicatively connected with the second desanding box and the second electric flat valve respectively.

[0021] Furthermore, the main filter assembly further includes a second pressure sensor, and two second pressure sensors are provided, one of which is arranged between the second inlet and the annulus, and the other is arranged between the second outlet and the fine pressure control manifold;

[0022] The control assembly is communicatively connected to the second pressure sensor.

[0023] Furthermore, a first filter screen is provided in each of the first desanding box and the second desanding box, and the first filter screen is located on the flow path of the drilling fluid in a posture facing the drilling fluid.

[0024] Furthermore, a second filter screen is provided in the fine pressure control manifold, and the second filter screen is located on the flow path of the drilling fluid in a posture facing the drilling fluid.

[0025] Furthermore, the fine pressure controlled drilling filtering device also includes a base, and the fine pressure controlled manifold and the control assembly are both fixedly connected to the base.

[0026] In a second aspect, the present invention further provides a drilling filtration method, which is based on the fine pressure controlled drilling filtration device and includes the following steps:

[0027] S100: The control assembly controls the main filter channel to open and the standby filter channel to close;

[0028] S200: After the control assembly detects that the pressure difference of the main filter channel has reached a preset value, it automatically controls the backup filter channel to open, then closes the main filter channel, and starts the automatic cleaning function of the main filter assembly to discharge the blockage.

[0029] Furthermore, in step S200, the control assembly transmits the pressure difference value to the remote control terminal, and the construction personnel manually control the backup filter assembly and the main filter assembly according to the pressure difference value.

[0030] In summary of the above technical solutions, the technical effects that can be achieved by the fine pressure controlled drilling filter device provided by the present invention are:

[0031] In the fine pressure controlled drilling filter device, the main filter assembly is connected with the annulus and the fine pressure controlled manifold through the main filter channel, so that the drilling fluid flowing out of the annulus will first enter the main filter channel, and then enter the fine pressure controlled manifold after filtration; the spare filter assembly is connected with the annulus and the fine pressure controlled manifold through the spare filter channel, so that the drilling fluid flowing out of the annulus will first enter the spare filter channel, and then enter the fine pressure controlled manifold after filtration; when there are many blockages such as rock cuttings, mud, foreign matter, etc. left after the drilling fluid is filtered, one of the filter channels will be blocked. At this time, the control assembly controls the other filter channel to open, and then closes the blocked filter channel. In this way, the normal operation of the fine pressure controlled drilling filter device is guaranteed.

[0032] It can be seen that compared with the existing technology, the use of the fine pressure controlled drilling filter device can switch to another filter channel after one of the filter channels is blocked to avoid clogging of the fine pressure controlled manifold. In this way, there is no need to switch the channel cleaning filter of the fine pressure controlled manifold, so that the fine pressure controlled drilling process can continue. At the same time, this also ensures the smooth flow of the drilling fluid, reduces pressure fluctuations, improves construction safety and the application scope of fine pressure controlled drilling technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0034] Figure 1 A front view of a fine pressure controlled drilling filtration device provided by an embodiment of the present invention;

[0035] Figure 2 A schematic diagram of the main passage of the fine pressure controlled drilling filtration device provided in an embodiment of the present invention.

[0036] Icons: 100-fine pressure control manifold; 200-control assembly; 300-first desanding box; 400-first electric flat valve; 500-second desanding box; 600-second electric flat valve. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0038] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] Some embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0040] During the implementation of fine pressure controlled drilling, due to the continuous occurrence of wellbore instability, a large number of blocks will be ejected, causing large fluctuations in wellhead pressure. In severe cases, the fine pressure controlled manifold will be blocked, requiring the channel to be switched every 10-20 minutes to clean the filter, and the fine pressure controlled drilling process will be forced to terminate. In addition, when the wellhead back pressure fluctuates, if the back pressure rises quickly or even becomes blocked, it is easy to cause untimely channel switching and well leakage. Excessive pressure fluctuations during pressure control will also cause downhole breathing effect, causing wellbore instability, oil and gas channels to be opened, and other problems, which will bring great safety hazards to the construction.

[0041] In view of this, the present invention provides a fine pressure controlled drilling filtration device, including a fine pressure controlled manifold 100, a main filter assembly, a spare filter assembly and a control assembly 200; the main filter assembly has a main filter channel for circulating drilling fluid to filter the drilling fluid, and the inlet and outlet of the main filter channel are connected to the annulus and the fine pressure controlled manifold 100 respectively; the spare filter assembly has a spare filter channel for circulating drilling fluid to filter the drilling fluid, and the inlet and outlet of the spare filter channel are also connected to the annulus and the fine pressure controlled manifold 100 respectively; the control assembly 200 is respectively communicated with the main filter assembly and the spare filter assembly to control the opening and closing of the main filter channel and the spare filter channel respectively, and the control assembly 200 is configured to open the other when one of the main filter channel and the spare filter channel is blocked, and then close the blocked one.

[0042] In the fine pressure controlled drilling filter device, the main filter assembly is connected to the annulus and the fine pressure controlled manifold 100 through the main filter channel, so that the drilling fluid flowing out of the annulus will first enter the main filter channel, and then enter the fine pressure controlled manifold 100 after filtration; the spare filter assembly is connected to the annulus and the fine pressure controlled manifold 100 through the spare filter channel, so that the drilling fluid flowing out of the annulus will first enter the spare filter channel, and then enter the fine pressure controlled manifold 100 after filtration; when there are many blockages such as rock cuttings, mud, and foreign matter left after the drilling fluid is filtered, one of the filter channels will be blocked. At this time, the control assembly 200 controls the other filter channel to open, and then closes the blocked filter channel. In this way, the normal operation of the fine pressure controlled drilling filter device is guaranteed.

[0043] It can be seen that compared with the prior art, the fine pressure controlled drilling filter device can switch to another filter channel after one filter channel is blocked to avoid clogging the fine pressure controlled manifold 100. In this way, there is no need to switch the channel cleaning filter of the fine pressure controlled manifold 100, so that the fine pressure controlled drilling process can continue. At the same time, this also ensures the smooth flow of the drilling fluid, reduces pressure fluctuations, and improves construction safety and the application scope of fine pressure controlled drilling technology.

[0044] The following combination Figure 1 and Figure 2 The structure of the fine pressure controlled drilling filter device provided in this embodiment is described in detail:

[0045] For the main filter assembly, refer to Figure 1 and Figure 2 The main filter assembly includes a first sand removal box 300, a first electric flat valve 400 and a first pressure sensor; the first sand removal box 300 has a first inlet and a first outlet, the first inlet is connected to the annulus, and the first outlet is connected to the fine pressure control manifold 100; there are two first electric flat valves 400, one of which is arranged between the first inlet and the annulus, and the other is arranged between the first outlet and the fine pressure control manifold 100; there are two first pressure sensors, one of which is arranged between the first inlet and the annulus, and the other is arranged between the first outlet and the fine pressure control manifold 100; the control assembly 200 is communicatively connected with the first sand removal box 300, the first electric flat valve 400 and the first pressure sensor respectively.

[0046] For spare filter assemblies, continue to refer to Figure 1 and Figure 2 The spare filter assembly includes a second desanding box 500, a second electric flat valve 600 and a second pressure sensor; the second desanding box 500 has a second inlet and a second outlet, the second inlet is connected to the annulus, and the second outlet is connected to the fine pressure control manifold 100; there are two second electric flat valves 600, one of which is arranged between the second inlet and the annulus, and the other is arranged between the second outlet and the fine pressure control manifold 100; there are two second pressure sensors, one of which is arranged between the second inlet and the annulus, and the other is arranged between the second outlet and the fine pressure control manifold 100; the control assembly 200 is respectively connected to the second desanding box 500, the second electric flat valve 600 and the second pressure sensor. In addition, a first filter is also arranged in the second desanding box 500.

[0047] For more information about the precision pressure control manifold 100, refer to Figure 1 and Figure 2 The fine pressure control manifold 100 is integrally welded to the base with the control assembly 200. A second filter screen is provided in the fine pressure control manifold 100. The second filter screen is located on the flow path of the drilling fluid in a posture facing the drilling fluid.

[0048] When in use, the drilling fluid enters the first desanding box 300 from the annulus through the connecting manifold between the first desanding box 300 and the annulus. The first desanding box 300 is provided with a first filter screen, thereby filtering and settling cuttings, mud and foreign matter, ensuring that the drilling fluid entering the fine pressure control manifold 100 is free of foreign matter, and the second filter screen in the fine pressure control manifold 100 can further filter the drilling fluid; when there are many blockages in the first desanding box 300, the control assembly 200 obtains the pressure difference of the main filter channel through the pressure values ​​transmitted by the two first pressure sensors. After the pressure difference reaches the set value, the control assembly 200 will automatically control the second electric flat valve 600 of the standby filter assembly to open, so that the standby filter channel is opened to maintain the normal operation of the fine pressure control drilling; after the second electric flat valve 600 is opened, the control assembly 200 will automatically control the closing of the first electric flat valve 400 to close the main filter channel, and at the same time start the automatic cleaning function of the first desanding box 300 to discharge the cuttings in the box.

[0049] In addition, the control assembly 200 can transmit the pressure value, pressure difference and other data of the filter channel to a remote control terminal, such as a tablet computer, so that the construction personnel can monitor the pressure difference and other data. When the pressure difference is found to be large, the construction personnel can manually operate and switch the filter channel through the control assembly 200 to achieve rock debris cleaning.

[0050] The fine pressure controlled drilling filter device has the function of realizing pressure detection and automatic switching of filter channels during the fine pressure controlled drilling process. It is simple and reliable to operate, with stable signal transmission, less manpower and short cleaning time, and can provide guarantee for the promotion and application of fine pressure controlled drilling technology.

[0051] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A fine pressure controlled drilling filtration device, characterized in that: include: A fine pressure control manifold (100), a main filter assembly, a spare filter assembly, and a control assembly (200); The main filter assembly has a main filter channel for circulating drilling fluid to filter the drilling fluid, and the inlet and outlet of the main filter channel are respectively connected to the annulus and the fine pressure control manifold (100); The standby filter assembly has a standby filter channel for circulating drilling fluid to filter the drilling fluid, and the inlet and outlet of the standby filter channel are also connected to the annulus and the fine pressure control manifold (100) respectively; The control assembly (200) is respectively connected to the main filter assembly and the backup filter assembly for controlling the opening and closing of the main filter channel and the backup filter channel respectively. The control assembly (200) is configured to open the main filter channel and the backup filter channel when one of the main filter channel and the backup filter channel is blocked, and then close the blocked one.

2. The fine pressure controlled drilling filtration device according to claim 1, characterized in that: The main filter assembly comprises a first sand removal box (300) and a first electric flat valve (400); The first desanding box (300) has a first inlet and a first outlet, the first inlet is connected to the annulus, and the first outlet is connected to the fine pressure control manifold (100); The first electric flat valve (400) is provided with two, one of which is arranged between the first inlet and the annulus, and the other is arranged between the first outlet and the fine pressure control manifold (100); The control assembly (200) is communicatively connected to the first sand removal box (300) and the first electric flat valve (400) respectively.

3. The fine pressure controlled drilling filtration device according to claim 2, characterized in that: The main filter assembly further comprises a first pressure sensor, wherein two first pressure sensors are provided, one of which is arranged between the first inlet and the annulus, and the other is arranged between the first outlet and the fine pressure control manifold (100); The control assembly (200) is communicatively connected to the first pressure sensor.

4. The fine pressure controlled drilling filtration device according to claim 3, characterized in that: The standby filter assembly comprises a second sand removal box (500) and a second electric flat valve (600); The second desanding box (500) has a second inlet and a second outlet, the second inlet is connected to the annulus, and the second outlet is connected to the fine pressure control manifold (100); The second electric flat valve (600) is provided with two, one of which is arranged between the second inlet and the annulus, and the other is arranged between the second outlet and the fine pressure control manifold (100); The control assembly (200) is communicatively connected to the second sand removal box (500) and the second electric flat valve (600) respectively.

5. The fine pressure controlled drilling filtration device according to claim 4, characterized in that: The main filter assembly further comprises a second pressure sensor, wherein two second pressure sensors are provided, one of which is arranged between the second inlet and the annulus, and the other is arranged between the second outlet and the fine pressure control manifold (100); The control assembly (200) is communicatively connected to the second pressure sensor.

6. The fine pressure controlled drilling filtration device according to claim 5, characterized in that: The first desanding box (300) and the second desanding box (500) are both provided with a first filter screen, and the first filter screen is located on the flow path of the drilling fluid in a posture facing the drilling fluid.

7. The fine pressure controlled drilling filtration device according to claim 1, characterized in that: A second filter screen is provided in the fine pressure control manifold (100), and the second filter screen is located on the flow path of the drilling fluid in a posture facing the drilling fluid.

8. The fine pressure controlled drilling filtration device according to any one of claims 1 to 7, characterized in that: The fine pressure controlled drilling filtering device also includes a base, and the fine pressure controlled manifold (100) and the control assembly (200) are both fixedly connected to the base.

9. A drilling filtration method, characterized in that: The fine pressure controlled drilling filtration device according to any one of claims 1 to 8 comprises the following steps: S100: The control assembly (200) controls the main filter channel to open and the standby filter channel to close; S200: After the control assembly (200) detects that the pressure difference of the main filter channel has reached a preset value, it automatically controls the backup filter channel to open, then closes the main filter channel, and starts the automatic cleaning function of the main filter assembly to discharge the blockage.

10. The drilling filtration method according to claim 9, characterized in that: In step S200, the control assembly (200) transmits the pressure difference value to the remote control terminal, and the construction personnel manually control the standby filter assembly and the main filter assembly according to the pressure difference value.

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