Intelligent blowout preventer, wellhead device and blowout prevention method

Abstract

The invention provides an intelligent blowout preventer, a wellhead device and a blowout prevention method. The intelligent blowout preventer is applied to the same-well injection-production process of a horizontal well containing an oil well controller. The device comprises a shell with a cross-shaped channel, the cross-shaped channel is composed of horizontal channels and a vertical channel for a polish rod to penetrate through, and the device further comprises two flashboards which are symmetrically installed in the horizontal channels on the two sides relative to the vertical channel. The two hydraulic cylinders are mounted on the shell and are used for pushing and pulling to enable the two gate plates to face each other to seal the polish rod or to deviate from each other to be separated from the polish rod; a locking structure is mounted on a cylinder barrel of the hydraulic cylinder; a digital sensor used for receiving instructions of an oil well controller is arranged on the locking structure, and the digital sensor drives the hydraulic cylinder to open or cut off the vertical channel. When high-pressure water in a casing pipe flows into a low-pressure oil pipe, the digital sensor can cut off a channel where a polish rod is located in time, and a horizontal well is stopped immediately; during normal production, the intelligent blowout preventer can ensure that a channel where the polish rod is located is kept unblocked.

Description

Technical Field

[0001] The invention belongs to the field of oil well equipment, and in particular relates to an intelligent blowout preventer, a wellhead device and a blowout prevention method. Background Art

[0002] Horizontal wells have a large contact area with the formation and a long penetration of the reservoir. They have the advantages of large single-well controlled reserves and high oil production rate, and are widely used in various oil and gas reservoirs. At present, horizontal wells in oil fields use a vertical well injection and production well pattern of vertical well water injection and horizontal well oil production to supplement formation energy. However, when horizontal wells pass through high-permeability zones, the injected water tends to advance rapidly along the high-permeability area or channel along the cracks, forming a dominant channel, causing the water content of the horizontal well to rise rapidly, and the large area of ​​residual oil outside the dominant channel is difficult to mobilize, resulting in less than ideal development results.

[0003] In order to improve the development effect of horizontal wells, a development method of line injection and line production was proposed, that is, a development technology that integrates water injection and oil production on the same horizontal well. However, since water injection is a high-pressure system and oil production is a low-pressure system, the two different pressure systems must exist in the same horizontal wellbore, which requires high reliability of downhole tool sealing. However, the wellbore conditions are quite complicated. If the downhole tool fails, high-pressure water in the casing will flow into the low-pressure oil pipe, which will cause a blowout accident. If a conventional oil production wellhead is used, the pressure bearing capacity is too small to meet the high-pressure water injection requirements; if a conventional water injection wellhead is used, the pressure level can be reached, but it cannot meet the oil production system. Summary of the invention

[0004] The purpose of the present invention is to provide an intelligent blowout preventer, a wellhead device and a blowout prevention method to overcome the above technical defects.

[0005] In order to solve the above technical problems, the present invention provides an intelligent blowout preventer, which is applied to the horizontal well injection and production process with an oil well controller, and includes a housing with a cross-shaped channel, the cross-shaped channel is composed of a horizontal channel and a vertical channel for a polished rod to pass through, and also includes two gates symmetrically installed in the horizontal channels on both sides with respect to the vertical channel, and two hydraulic cylinders installed on the housing for pushing and pulling so that the two gates face each other to seal the polished rod or move away from each other to separate from the polished rod;

[0006] A locking structure is installed on the cylinder barrel of the hydraulic cylinder;

[0007] A digital sensor for receiving instructions from the oil well controller is provided on the locking structure. The digital sensor drives the hydraulic cylinder. After the cylinder body supplies hydraulic oil, it pushes the piston rod to move to open or cut off the vertical channel.

[0008] The gate plates are inlaid with sealing rubber cores. Two hydraulic cylinders push and pull the two gate plates to make the two sealing rubber cores hold the seal or loosen and detach from the polished rod.

[0009] When the two sealant cores hold the sealing polished rod, the vertical channel is cut off;

[0010] When the two sealant cores are loosened and separated from the polished rod, the vertical channel is unblocked.

[0011] A groove for the piston rod of the hydraulic cylinder to be embedded is provided on the gate plate.

[0012] The locking structure comprises an outer protective sleeve and a locking screw. The outer protective sleeve is installed on the hydraulic cylinder and the inner cavities of the two are communicated. The locking screw is arranged in the inner cavity and is coaxially connected with the piston rod of the hydraulic cylinder.

[0013] A manual locking fixture is installed at the end of each locking screw away from the polished rod.

[0014] The present invention also provides a wellhead device, which at least comprises an intelligent blowout preventer.

[0015] A blowout prevention method, using a wellhead device to perform the following steps:

[0016] In normal working state, the oil well controller sends a command to the digital sensor. After receiving the command, the digital sensor drives the piston rods of the two hydraulic cylinders to move away from each other to separate from the polished rod, the vertical channel is opened, and the horizontal well implements the same-well injection and production process normally.

[0017] When high-pressure water in the casing of a horizontal well leaks into the low-pressure oil pipe, the oil well controller sends a command to the digital sensor. After receiving the command, the digital sensor drives the piston rods of the two hydraulic cylinders to move towards each other to seal the bare rod. The vertical channel is cut off and the horizontal well is stopped.

[0018] The beneficial effects of the present invention are as follows:

[0019] When high-pressure water in the casing leaks into the low-pressure oil pipe, the intelligent blowout preventer provided by the present invention can cut off the channel where the bare rod is located in time, so that the horizontal well can be stopped immediately. It can not only effectively avoid blowout accidents caused by failure of downhole tools, but also ensure that the channel where the bare rod is located remains unobstructed during normal production. That is, combined with the downhole supporting tools for injection and production in the same well, water injection and oil production can be achieved in the same well, thereby reducing the number of new wells drilled, improving the utilization rate of old wells, achieving a certain range of well network optimization, and improving oil reservoir recovery.

[0020] In order to make the above contents of the present invention more clearly understood, preferred embodiments are given below and described in detail in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural diagram of the intelligent blowout preventer.

[0022] Figure 2 It is a structural schematic diagram of a wellhead device including an intelligent blowout preventer.

[0023] Description of reference numerals:

[0024] 100. Shell;

[0025] 200. Gate; 201. Sealing rubber core;

[0026] 300. Hydraulic cylinder;

[0027] 400. Locking mechanism;

[0028] 500. Digital sensor. DETAILED DESCRIPTION

[0029] The following describes the implementation of the present invention through specific embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0030] It should be noted that, in the present invention, the up, down, left and right in the figure are regarded as the up, down, left and right of the intelligent blowout preventer described in this specification.

[0031] The exemplary embodiments of the present invention are now described with reference to the accompanying drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to disclose the present invention in detail and completely and to fully convey the scope of the present invention to those skilled in the art. The terms used in the exemplary embodiments shown in the accompanying drawings are not intended to limit the present invention. In the accompanying drawings, the same units / elements are marked with the same reference numerals.

[0032] Unless otherwise specified, the terms (including technical terms) used herein have the commonly understood meanings to those skilled in the art. In addition, it is understood that the terms defined in commonly used dictionaries should be understood to have the same meanings as those in the context of the relevant fields, and should not be understood as idealized or overly formal meanings.

[0033] This embodiment relates to an intelligent blowout preventer, which is applied to a horizontal well injection and production process containing an oil well controller. The horizontal well injection and production process is to have two different pressure systems in a horizontal wellbore. The two different pressure systems are a high-pressure water injection system and a low-pressure oil production system, so as to achieve both water injection and oil production in the same well.

[0034] See also Figure 1 The intelligent blowout preventer includes a shell 100 having a cross-shaped channel, wherein the cross-shaped channel is composed of a horizontal channel and a vertical channel, wherein the vertical channel is used for the polished rod to pass through, and the horizontal channel is used for installing other components.

[0035] Continue reading Figure 1The intelligent blowout preventer also includes two gates 200 symmetrically installed in the horizontal channels on both sides with respect to the vertical channel, and two hydraulic cylinders 300 installed on the housing 100 for pushing and pulling the two gates 200 to seal the polished rod toward each other or to move away from each other to separate from the polished rod.

[0036] according to Figure 1 It can be seen that the overall structure of the intelligent blowout preventer is symmetrical.

[0037] A locking structure 400 is installed on the cylinder barrel of the hydraulic cylinder 300. The locking structure 400 is used to push and pull the piston rod of the hydraulic cylinder 300. Specifically:

[0038] A digital sensor 500 for receiving instructions from the oil well controller is provided on the locking structure 400. The digital sensor 500 drives the hydraulic cylinder 300. After the cylinder body supplies hydraulic oil, it pushes the piston rod to move to open or cut off the vertical channel. How to open and cut the vertical channel for the light rod to pass through will be described in detail below.

[0039] Under normal production conditions, the vertical channel of the intelligent blowout preventer is open, and the bare rod is working normally at this time; but once the high-pressure water in the casing leaks into the low-pressure oil pipe, an alarm sounds at the well site, and the oil well controller issues a well stop command. After receiving the command, the digital sensor 500 drives the two hydraulic cylinders 300 to move towards each other until the two gates 200 seal the bare rod, and the vertical channel is cut off at this time.

[0040] like Figure 1 As shown, the gate plates 200 are inlaid with a sealant core 201 (in an L shape), and two hydraulic cylinders 300 push and pull the two gate plates 200 to make the two sealant cores 201 hold the seal or release and separate from the polished rod. Specifically:

[0041] When the two sealant cores 201 hold the sealing polished rod, the vertical channel is cut off;

[0042] When the two sealant cores 201 are loosened and separated from the polished rod, the vertical passage is unblocked.

[0043] That is to say, the gate plate 200 is provided with a sealing rubber core 201 , and the sealing rubber core 201 can be moved by pushing and pulling the gate plate 200 , thereby enabling the two sealing rubber cores 201 to hold the sealing polished rod or release and detach from the polished rod.

[0044] Reference Figure 1 A groove is provided on the gate plate 200 for the piston rod of the hydraulic cylinder 300 to be embedded in. One end of the piston rod of the hydraulic cylinder 300 is connected to the groove (also called a card slot) on the gate plate 200 , and the other end is connected to the locking structure 400 .

[0045] See also Figure 1The locking structure 400 includes an outer protective sleeve and a locking screw. The outer protective sleeve is installed on the hydraulic cylinder 300 and the inner cavities of the two are connected. The locking screw is arranged in the inner cavity and is coaxially connected with the piston rod of the hydraulic cylinder 300.

[0046] It should be noted here that the locking screw is arranged in the inner cavity and coaxially connected to the piston rod of the hydraulic cylinder 300, which means that one end of the locking screw is inserted into the piston rod so that the axial center line of the locking screw overlaps with the axial center line of the piston rod, and the locking screw and the piston rod are connected to each other.

[0047] Normally, the locking structure 400 can realize the opening and closing of the vertical channel, but if the well needs to be shut down for a long time, manual locking is required. Therefore, a manual locking tool is installed at the end of each locking screw away from the light rod (not shown in the figure). If the well needs to be shut down for a long time, the special manual locking tool can be connected to the locking screws at both ends of the smart blowout preventer to rotate the locking gate 200.

[0048] Please refer to Figure 2 The present embodiment also provides a wellhead device, which at least includes an intelligent blowout preventer. The intelligent blowout preventer is installed on the wellhead device. The oil pressure gauge of the wellhead device can be used to obtain the tubing pressure, and whether the high-pressure water in the casing has entered the low-pressure tubing can be determined based on the tubing pressure. In addition, a reasonable blowout prevention pressure can be set for the intelligent blowout preventer. When the oil pressure gauge of the wellhead device shows that the pressure in the tubing is higher than the design pressure, the system overpressure alarm, injection stop, pumping unit stop, and wellhead sucker rod blowout preventer, wellhead water injection valve, and wellhead production valve can be automatically closed in sequence, thereby preventing the high-pressure water in the casing from entering the low-pressure tubing when the downhole tool fails, causing a blowout accident, and avoiding safety and environmental risks.

[0049] It should be noted that the wellhead device belongs to the prior art and will not be described in detail here.

[0050] The intelligent blowout preventer in the wellhead device includes a housing 100 with a cross-shaped channel, which is composed of a horizontal channel and a vertical channel for a polished rod to pass through. It also includes two gates 200 symmetrically installed in the horizontal channels on both sides with respect to the vertical channel, and two hydraulic cylinders 300 installed on the housing 100 for pushing and pulling to make the two gates 200 face each other to seal the polished rod or move away from each other to separate from the polished rod. A locking structure 400 is installed on the cylinder barrel of the hydraulic cylinder 300, and a digital sensor 500 for receiving instructions from the oil well controller is provided on the locking structure 400. The digital sensor 500 drives the hydraulic cylinder 300 to open or cut off the vertical channel. The gates 200 are all inlaid with a sealing rubber core 201. The two hydraulic cylinders 300 push and pull the two gates 200 to make the two sealing rubber cores 201 hold the sealing rod or release it to separate from the polished rod; when the two sealing rubber cores 201 hold the sealing rod, the vertical channel is cut off; when the two sealing rubber cores 201 release and separate from the polished rod, the vertical channel is unblocked. The gate plate 200 is provided with a groove for the piston rod of the hydraulic cylinder 300 to be inserted. The locking structure 400 includes an outer protective sleeve and a locking screw. The outer protective sleeve is installed on the hydraulic cylinder 300 and the inner cavities of the two are connected. The locking screw is arranged in the inner cavity and is coaxially connected with the piston rod of the hydraulic cylinder 300. A manual locking tool is installed at the end of each locking screw away from the polished rod.

[0051] This embodiment also provides a blowout prevention method, which uses a wellhead device to perform the following steps:

[0052] In normal working state, the oil well controller sends a command to the digital sensor 500. After receiving the command, the digital sensor 500 drives the piston rods of the two hydraulic cylinders 300 to move away from each other to separate from the polished rod, and the vertical channel is opened. The horizontal well normally implements the same-well injection and production process.

[0053] When high-pressure water in the casing of the horizontal well leaks into the low-pressure oil pipe, the oil well controller sends a command to the digital sensor 500. After receiving the command, the digital sensor 500 drives the piston rods of the two hydraulic cylinders 300 to move towards each other to seal the bare rod, the vertical channel is cut off, and the horizontal well is stopped.

[0054] In summary, the intelligent blowout preventer, wellhead device and blowout prevention method provided by the present invention can not only effectively prevent the high-pressure water in the casing from entering the low-pressure oil pipe when the downhole tool fails, causing a blowout accident and avoiding safety and environmental risks; at the same time, combined with the downhole supporting tools for injection and production in the same well, it is possible to achieve both water injection and oil production in the same well, reduce the number of new wells drilled, improve the utilization rate of old wells, achieve well network optimization within a certain range, and improve the recovery rate of oil reservoirs.

[0055] Those skilled in the art will appreciate that the above-mentioned embodiments are specific examples for implementing the present invention, and in actual applications, various changes may be made thereto in form and detail without departing from the spirit and scope of the present invention.

Claims

1. Intelligent blowout preventer, applied to horizontal well injection and production process with oil well controller, characterized by: It comprises a housing (100) having a cross-shaped channel, wherein the cross-shaped channel is composed of a horizontal channel and a vertical channel for a polished rod to pass through, and further comprises two gates (200) symmetrically installed in the horizontal channels on both sides with respect to the vertical channel, and two hydraulic cylinders (300) installed on the housing (100) for pushing and pulling the two gates (200) so as to face each other to seal the polished rod or to move away from each other to separate from the polished rod; A locking structure (400) is installed on the cylinder barrel of the hydraulic cylinder (300); A digital sensor (500) for receiving instructions from the oil well controller is provided on the locking structure (400). The digital sensor (500) drives the hydraulic cylinder (300). After the cylinder body supplies hydraulic oil, it pushes the piston rod to move, so as to open or cut off the vertical channel.

2. The intelligent blowout preventer according to claim 1, characterized in that: The gate plates (200) are all inlaid with a sealing rubber core (201), and the two hydraulic cylinders (300) push and pull the two gate plates (200) so that the two sealing rubber cores (201) hold the seal or release and separate from the polished rod; When the two sealing rubber cores (201) embrace and seal the polished rod, the vertical channel is cut off; When the two sealing rubber cores (201) are loosened and separated from the polished rod, the vertical channel is unblocked.

3. The intelligent blowout preventer according to claim 2, characterized in that: The gate plate (200) is provided with a groove for the piston rod of the hydraulic cylinder (300) to be embedded.

4. The intelligent blowout preventer according to claim 2, characterized in that: The locking structure (400) comprises an outer protective sleeve and a locking screw, wherein the outer protective sleeve is mounted on the hydraulic cylinder (300) and the inner cavities of the two are in communication, and the locking screw is disposed in the inner cavity and is coaxially connected to the piston rod of the hydraulic cylinder (300).

5. The intelligent blowout preventer according to claim 4, characterized in that: A manual locking tool is installed at the end of each locking screw far away from the polished rod.

6. A wellhead device, characterized in that: At least comprising the intelligent blowout preventer according to any one of claims 1-5.

7. A blowout prevention method, characterized in that: The wellhead device according to claim 6 is used to perform the following steps: In a normal working state, the oil well controller sends an instruction to the digital sensor (500), and after receiving the instruction, the digital sensor (500) drives the piston rods of the two hydraulic cylinders (300) to move away from each other to separate from the polished rod, the vertical channel is opened, and the horizontal well implements the same-well injection and production process normally; When high-pressure water in the casing of the horizontal well leaks into the low-pressure oil pipe, the oil well controller sends a command to the digital sensor (500). After receiving the command, the digital sensor (500) drives the piston rods of the two hydraulic cylinders (300) to move towards each other to seal the bare rod, and the vertical channel is cut off, and the horizontal well is shut down.

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