Rotary steerable drilling system test matching system wellbore matching system

Abstract

A kind of rotary steerable drilling system test matching system wellbore matching system, it is mainly by wellhead device, wellbore system, mobile opening and closing wellbore are sequentially sealed and connected to be formed and then be supported by wellbore support;The wellbore system is arranged from high to low by inclined straight section wellbore, curved section wellbore, horizontal section wellbore and is tangentially connected;The horizontal section wellbore is divided into first horizontal section wellbore, second horizontal section wellbore two parts, and the two parts are sealed and connected by mobile opening and closing wellbore.This application is dedicated to solve the problem that rotary steerable product can simulate drill string through small radius of curvature in the process of ground simulation test;Develop the force situation research of drill string in small radius of curvature well in the process of drilling, overall improve the test ability of rotary steerable drilling system test matching system, and solve the industry problem of drilling fluid pollution environment in test site.

Description

Technical Field

[0001] This invention relates to the field of oil and gas drilling and production, specifically to providing an indoor ground simulation test device for rotary guide products in the oil and gas drilling and production industry. Background Technology

[0002] With the increasing demand for special oil wells such as ultra-deep wells, high-difficulty directional wells, horizontal wells, extended reach wells, and horizontal branch wells in the development of special oil reservoirs in domestic oilfields, research on rotary steerable drilling technology has become increasingly active. In order to research and develop rotary steerable technology products, a reliable ground simulation test device is one of the essential conditions. Ground simulation tests are conducted before the well is run to verify and test the functional principle, guiding force and guiding effect of the rotary steerable tool, and to assess the reliability of the tool product.

[0003] The various rotary steerable drilling test devices established by oilfield companies both domestically and internationally lack wellbore simulation systems. This prevents them from simulating the throughput of drill strings with small curvature radii, or studying the stress conditions of the drill string in wells with small curvature radii during drilling. Because of the lack of wellbore simulation systems, drilling fluid discharge lacks a dedicated return channel and is instead discharged directly, leading to arbitrary discharge of drilling fluid at the test site and potentially causing environmental pollution. Summary of the Invention

[0004] This invention provides a test system and wellbore support system for rotary steerable drilling systems, aiming to solve the problem of simulating the passage of drill strings with small curvature radii during ground simulation tests of rotary steerable products; to conduct research on the stress of drill strings in wells with small curvature radii during drilling; to comprehensively improve the testing capabilities of rotary steerable drilling system test systems; and to solve the industry problem of drilling fluid pollution at test sites.

[0005] The technical solution adopted in this invention is:

[0006] A test supporting system for a rotary steerable drilling system is provided, which mainly consists of a wellhead device, a wellbore system, and a movable opening and closing wellbore connected in sequence and sealed, and then supported by a wellbore support. The wellbore system is composed of a straight section of wellbore, a curved section of wellbore, and a horizontal section of wellbore arranged from high to low and connected tangentially. The horizontal section of wellbore is divided into two parts: a first horizontal section of wellbore and a second horizontal section of wellbore, which are connected by a movable opening and closing wellbore.

[0007] The wellhead device includes a wellhead cylinder, the lower end of which is a wellhead connecting flange and the upper end of which is a wellhead flange. The wellhead flange is connected to a sealing seat, and a sealing gland is installed on the sealing seat to seal the drill string in the wellhead cylinder. An oil plug is installed on the middle wall of the wellhead cylinder.

[0008] The movable opening and closing well casing includes an upper opening and closing well casing and a lower opening and closing well casing, which are rotatably connected to a hinge shaft, which is mounted on the vehicle body. The upper opening and closing well casing cylinder is connected to the outer wall of the upper opening and closing well casing through a transmission arm to realize the opening and closing movement of the upper opening and closing well casing. The lower opening and closing well casing cylinder is connected to the outer wall of the lower opening and closing well casing through a transmission arm to realize the opening and closing movement of the lower opening and closing well casing. The upper opening and closing well casing and the lower opening and closing well casing are connected in a closed state by locking bolts and locking nuts. In this closed state, the first horizontal section of the well casing and the second horizontal section of the well casing are sealed by axial and radial sealing gaskets or rings.

[0009] The movable opening and closing well casing is equipped with wheels, and tracks are arranged parallel to each other in the axial direction perpendicular to the horizontal section of the well casing. The movable opening and closing well casing moves back and forth along the tracks automatically or manually via the wheels.

[0010] The wellhead assembly includes a wellhead connecting flange at the lower end of the wellhead cylinder, flanges at both ends of the inclined and straight sections of the wellhead cylinder, flanges at both ends of the curved sections of the wellhead cylinder, and flanges at both ends of the horizontal sections of the wellhead cylinder. When one side of each adjacent flange is a convex flange, the other side is a concave flange. After the convex and concave flanges are matched and sealed with O-rings, they are connected as one unit by high-strength double-ended studs and high-strength nuts.

[0011] The drill string has an internal hollow structure. The inner walls of the wellhead cylinder, the inclined straight section wellhead, the curved section wellhead, the first horizontal section wellhead, the second horizontal section wellhead, and the movable opening and closing wellhead of the wellhead device form an annulus with the outer wall of the drill string. The drilling fluid outlet is opened on the wall of the second horizontal section wellhead.

[0012] This invention employs a wellbore-supporting system to simulate wells with small curvature, enabling the study of drill string throughput under small curvature radii during surface simulation tests of rotary steerable drilling products, as well as the study of drill string stress in wells with small curvature radii during drilling, thus improving the testing capabilities of rotary steerable drilling systems. Simultaneously, the wellbore-supporting system establishes an annulus channel, allowing the test slurry to enter the drilling fluid treatment system along this dedicated channel throughout the test, resolving the environmental pollution problem caused by direct discharge of drilling fluid during testing. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of the present invention;

[0014] Figure 2 This is a schematic diagram of the wellhead device of the present invention;

[0015] Figure 3-1 This is a schematic cross-sectional view of the movable opening and closing well casing in the closed state according to the present invention;

[0016] Figure 3-2 This is a schematic cross-sectional view of the movable opening and closing well shaft in the open state according to the present invention;

[0017] Figure 4 This is a schematic diagram of the wellhead device and the connection between the wellbore of the present invention;

[0018] Figure 5 This is a schematic diagram showing the connection between the movable opening and closing well casing and the horizontal section of the well casing according to the present invention. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the present invention clearer and more explicit, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0020] This invention discloses a test system and wellbore support system for rotary steerable drilling systems. It aims to solve the problems encountered during ground simulation tests of rotary steerable products, including simulating the throughput of drill strings with small radii of curvature and studying the stress on the drill string in wells with small radii of curvature during drilling. This comprehensively improves the testing capabilities of rotary steerable drilling system test systems and addresses the industry-wide problem of drilling fluid pollution at test sites.

[0021] Reference Figure 1 A test system for a rotary steerable drilling system, comprising a wellhead device 1, a wellbore system, and a movable, openable wellbore 4, sequentially sealed and connected, and supported by a wellbore support 3. The wellbore system consists of a straight section 2-1, a curved section 2-2 (the curved section 2-2 is prefabricated using casing bent to a pre-designed bending radius), and horizontal sections 2-3 arranged from high to low and connected tangentially. The horizontal sections 2-3 are divided into a first horizontal section 2-3-1 and a second horizontal section 2-3-2, which are sealed and connected by the movable, openable wellbore 4. The wellbore system uses casing to simulate the well depth structure, and the wellbore support 3 is a welded steel truss structure installed on the ground.

[0022] Among them, reference Figure 2 The wellhead device 1 includes a wellhead cylinder 1-7, with a wellhead connecting flange 1-8 at the lower end and a wellhead flange 1-5 at the upper end. The wellhead flange 1-5 is connected to a sealing seat 1-4, and a sealing gland 1-2 is sealed and installed on the sealing seat 1-4, thereby sealing the drill string 1-1 in the wellhead cylinder 1-7. However, an annular space is formed between the outer wall of the drill string 1-1 and the inner wall of the wellhead cylinder 1-7. An oil plug 1-6 is installed on the middle wall of the wellhead cylinder 1-7. The sealing gland 1-2, the sealing seat 1-4, and the drill string 1-1 are sealed by a sealing gasket or ring 1-3.

[0023] Reference Figure 3-1 , 3-2The movable opening and closing well shaft 4 includes an upper opening and closing well shaft 4-1 and a lower opening and closing well shaft 4-6. The upper opening and closing well shaft 4-1 and the lower opening and closing well shaft 4-6 are rotatably connected to a hinge shaft 4-2, and the hinge shaft 4-2 is mounted on a vehicle body 4-4. The upper opening and closing well shaft cylinder 4-3 is connected to the outer wall of the upper opening and closing well shaft 4-1 through a transmission arm to realize the opening and closing movement of the upper opening and closing well shaft 4-1. The lower opening and closing well shaft cylinder 4-7 is connected to the outer wall of the lower opening and closing well shaft 4-6 through a transmission arm to realize the opening and closing movement of the lower opening and closing well shaft 4-6. The upper opening and closing well shaft 4-1 and the lower opening and closing well shaft 4-6 are connected in a closed state by locking bolts 4-8 and locking nuts 4-9. In this closed state, the first horizontal section well shaft 2-3-1 and the second horizontal section well shaft 2-3-2 are sealed by axial and radial sealing gaskets or rings 4-5 to prevent leakage.

[0024] The movable opening and closing well shaft 4 is equipped with wheels on its vehicle body 4-4, and a track is arranged parallel to the axial direction of the horizontal section well shaft 2-3. The movable opening and closing well shaft 4 moves back and forth along the track, i.e., perpendicular to the axial direction of the horizontal section well shaft, automatically or manually via the wheels.

[0025] Reference Figure 4 The wellhead connecting flange 1-8 at the lower end of the wellhead cylinder 1-7 of the wellhead device 1, the flanges at both ends of the inclined straight section wellhead 2-1, the flanges at both ends of the curved section wellhead 2-2, and the flanges at both ends of the horizontal section wellhead 2-3, when one side of each adjacent flange is a convex flange 4-16, the other side is a concave flange 4-12. The convex and concave flanges are adapted to each other and sealed by O-ring seals 4-13. After assembly, they are connected into one piece by high-strength double-ended studs 4-14 and high-strength nuts 4-15.

[0026] Reference Figure 5 The drill string 1-1 has an internal hollow structure. The inner walls of the wellhead cylinder 1-7, the inclined straight section wellbore 2-1, the curved section wellbore 2-2, the first horizontal section wellbore 2-3-1, the second horizontal section wellbore 2-3-2, and the movable opening and closing wellbore 4 of the wellhead device 1 form an annulus with the outer wall of the drill string 1-1. The drilling fluid outlet 4-10 is opened on the wall of the second horizontal section wellbore 2-3-2. After the drilling fluid passes through the inside of the drill string and reaches the rotating tool, it enters the mud treatment system through the annulus from the drilling fluid outlet 4-10.

[0027] The working process of this invention can be simplified as follows:

[0028] Force (referred to as drill pressure) is applied to the drill pipe head. The drill pipe can be lowered from the wellhead device 1. After the lowered drill pipes are connected to each other, they form the drill string 1-1. According to the process requirements, the drill pipe can be lowered in the standard length or the specified length each time. The drill pipe passes through the inclined straight section of the wellbore 2-1 and enters the curved section of the wellbore 2-2. The curved section of the wellbore 2-2 is prefabricated by bending the casing according to the pre-designed bending radius. The bending radius is determined according to the small curvature radius wellbore required for simulation. The drill pressure applied to the drill pipe head can be measured according to the drill pipe passing through the curved section of the wellbore 2-2. The relationship between the drill string diameter, the curvature of the curved section, and the applied drill pressure is established. The simulation study of the drill string's passage through small curvature radius provides technical support for oilfield drilling.

[0029] When the drill pipe passes through the curved section of the wellbore 2-2 and reaches the horizontal section of the wellbore 2-3, the horizontal section of the wellbore is arranged in two sections with an opening in the middle. The length of the opening is determined based on the length of the drill pipe each time it is lowered. The two disconnected sections of the horizontal wellbore are connected by a movable opening and closing wellbore.

[0030] Drilling pressure and rotational torque are applied to the drill pipe at the head of the wellhead device 1, causing the entire drill string to rotate, thereby driving the rotary tool to rotate and conduct simulated drilling operations. After the drilling fluid flows through the inner wall of the drill string 1-1 and passes through the rotary tool, it cools the drill bit and tool on the one hand, and carries away the rock cuttings in the drilling process on the other hand. The drilling fluid containing rock cuttings passes through the annular channel formed by the inner wall of the wellhead device 1, the inclined straight section of the wellbore 2-1, the curved section of the wellbore 2-2, the horizontal section of the wellbore 2-3, and the movable opening and closing wellbore 4 and the outer wall of the drill string 1-1, and enters the mud treatment system from the drilling fluid outlet 4-10. Throughout the experiment, drill pipes needed to be connected after each drilling depth. Due to the size of the well system, the wellhead device 1 is typically nearly 20 meters above the ground. Connecting drill pipes at the wellhead device 1 is inconvenient and unsafe. Therefore, connecting single drill pipes on the ground floor is safe and reliable. When a single drill pipe needs to be connected, the movable opening and closing well casing 4 opens, and the annular fluid flows into the water tank located in the vehicle body 4-4 of the movable opening and closing well casing 4. The movable opening and closing well casing 4 can automatically or manually move away in a direction perpendicular to the horizontal well casing axis. After connecting a single drill pipe, the movable opening and closing well casing 4 returns along the same path, connected by the first horizontal section well casing 2-3-1, the second horizontal section well casing 2-3-2, the upper opening and closing well casing 4-1, the lower opening and closing well casing 4-6, and the sealing gasket or ring 4-5. When the movable opening and closing well casing 4 is closed, the sealing gasket or ring 4-5 seals the horizontal section well casing 2-3-1 and the horizontal section well casing 2-3-2, preventing leakage. The entire test process was conducted in a closed annulus with no leakage, solving the industry problem of drilling fluid easily polluting the environment during the test.

[0031] Throughout the experiment, by establishing the interrelationship between drilling pressure, torque, and wellbore vibration in the curved section, the stress on the drill string in a well with a small radius of curvature during drilling was studied, providing a technical basis for the development of wells with small radius of curvature in oilfields.

Claims

1. A test system and wellbore support system for a rotary steerable drilling system, characterized in that, It is mainly composed of a wellhead device (1), a well shaft system, and a movable opening and closing well shaft (4) connected in sequence and then supported by a well shaft support (3); The wellbore system consists of a straight section (2-1), a curved section (2-2), and a horizontal section (2-3) arranged from high to low and connected tangentially. The curved section of the wellbore (2-2) is pre-formed by bending the oil casing according to a pre-designed bending radius; The horizontal section of the wellbore (2-3) is divided into two parts: the first horizontal section of the wellbore (2-3-1) and the second horizontal section of the wellbore (2-3-2). The two parts are sealed together by a movable opening and closing wellbore (4). The wellhead device (1) includes a wellhead cylinder (1-7), the lower end of which is a wellhead connecting flange (1-8) and the upper end is a wellhead flange (1-5). The wellhead flange (1-5) is connected to a sealing seat (1-4), and a sealing gland (1-2) is sealed and installed on the sealing seat (1-4) to seal and install the drill string (1-1) in the wellhead cylinder (1-7); an oil plug (1-6) is installed on the middle wall of the wellhead cylinder (1-7). The movable opening and closing well casing (4) includes an upper opening and closing well casing (4-1) and a lower opening and closing well casing (4-6). The upper opening and closing well casing (4-1) and the lower opening and closing well casing (4-6) are rotatably connected to a hinge shaft (4-2), and the hinge shaft (4-2) is mounted on the vehicle body (4-4). The upper opening and closing well casing cylinder (4-3) is connected to the outer wall of the upper opening and closing well casing (4-1) through a transmission arm to realize the opening and closing movement of the upper opening and closing well casing (4-1). The lower opening and closing well casing cylinder (4-7) is connected to the outer wall of the lower opening and closing well casing (4-6) through a transmission arm. The wall connection enables the opening and closing movement of the lower opening and closing well shaft (4-6); the upper opening and closing well shaft (4-1) and the lower opening and closing well shaft (4-6) are connected in a closed state by locking bolts (4-8) and locking nuts (4-9). In this closed state, the first horizontal section well shaft (2-3-1) and the second horizontal section well shaft (2-3-2) are sealed by axial and radial sealing gaskets or rings (4-5) to prevent leakage. The upper opening and closing well shaft cylinder (4-3) and the lower opening and closing well shaft cylinder (4-7) are both mounted on the vehicle body (4-4). The movable opening and closing well shaft (4) is equipped with wheels on its vehicle body (4-4), and a track is arranged parallel to the axial direction perpendicular to the horizontal section of the well shaft (2-3). The movable opening and closing well shaft (4) moves back and forth along the track automatically or manually by means of the wheels. When a single drill string needs to be connected, the movable opening and closing wellbore (4) opens, and the annular liquid flows into the water tank arranged in the vehicle body (4-4) of the movable opening and closing wellbore (4). The movable opening and closing wellbore (4) leaves in a direction perpendicular to the axial direction of the horizontal wellbore. After connecting a single drill string, the movable opening and closing wellbore (4) returns along the path and is connected through the first horizontal section wellbore (2-3-1), the second horizontal section wellbore (2-3-2), the upper opening and closing wellbore (4-1), the lower opening and closing wellbore (4-6), and the sealing gasket or ring (4-5). When the movable opening and closing wellbore (4) is closed, the first horizontal section wellbore (2-3-1) and the second horizontal section wellbore (2-3-2) are sealed by the sealing gasket or ring (4-5) to prevent leakage. The drill string (1-1) adopts an internal hollow structure. The wellhead cylinder (1-7) of the wellhead device (1), the inclined straight section wellbore (2-1), the curved section wellbore (2-2), the first horizontal section wellbore (2-3-1), the second horizontal section wellbore (2-3-2), and the inner wall of the movable opening and closing wellbore (4) form an annulus with the outer wall of the drill string (1-1). The drilling fluid outlet (4-10) is opened on the wall of the second horizontal section wellbore (2-3-2). The wellhead connecting flange (1-8) at the lower end of the wellhead cylinder (1-7) of the wellhead device (1), the flanges at both ends of the inclined straight section wellhead (2-1), the flanges at both ends of the curved section wellhead (2-2), and the flanges at both ends of the horizontal section wellhead (2-3) of each adjacent flange are arranged such that one side is a convex flange (4-16) and the other side is a concave flange (4-12). After the convex and concave flanges are matched and sealed with O-ring seals (4-13), they are connected into one piece by high-strength double-ended studs (4-14) and high-strength nuts (4-15).

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