High-pressure oil and gas well testing induced blowout valve

Abstract

The invention discloses a blowout inducement valve for testing high-pressure oil and gas wells, comprising a main pipeline, a sliding pipe, a trapezoidal stop block, a stamping plate, a telescopic spring assembly, a flow limiting rod, a drainage pipe and a connecting joint; the sliding pipe, the trapezoidal stop block and the flow limiting rod are sequentially connected from top to bottom and coaxially arranged in the main pipeline; a first connecting ring and a second connecting ring are fixed on the inner wall of the main pipeline; the trapezoidal stop block is inserted in the first connecting ring, the stamping plate is sleeved and fixed on the outer wall of the sliding pipe located above the first connecting ring, and the telescopic spring assembly is arranged between the stamping plate and the first connecting ring; an annular flow limiting block is arranged on the upper outer wall of the flow limiting rod, and the annular flow limiting block It is arranged in the main pipeline in a manner that there is a gap; the drainage pipe is sleeved on the outer side of the lower part of the flow limiting rod in a manner that there is a gap, and its top outer wall is fixed on the inner wall of the second connecting ring, and a number of drainage holes are evenly distributed along the circumferential direction on the bottom side wall; two pressure transmission hole groups are symmetrically opened on the side wall of the main pipeline located above the stamping plate; at least two rows of diversion hole groups are opened on the bottom side wall of the sliding tube; the blowout induced valve has a simple structure, convenient operation, high stability and strong reliability, can operate stably under high temperature and high pressure, and effectively control the speed at which formation products flow into the wellbore, thereby realizing the blowout induced function under the premise of ensuring well control safety.

Description

Technical Field

[0001] The invention relates to the technical field of oil testing and production technology, and in particular to a blowout inducing valve for testing high-pressure oil and gas wells. Background Art

[0002] After the well is drilled, the first step in the oil testing phase is to induce fluid flow, that is, to try to reduce the bottom hole pressure so that the bottom hole pressure is lower than the oil layer pressure, so that oil and gas can flow into the well. This step is the first process of oil testing.

[0003] As oil and gas exploration develops in depth, deep layers have become the key targets and popular areas of oil and gas exploration. In the early stages of exploration and development, there are many wells with high formation pressure, especially some gas wells. In order to prevent blowouts, high-density mud is often used to pressurize the wells. This makes it very difficult to induce blowouts. It is difficult to induce blowouts successfully using conventional oil testing processes. Using negative pressure to induce blowouts is prone to accidents due to the large pressure difference of gas wells. It is difficult to achieve switching using the switch valve of the test tool itself when the pressure difference is large. Summary of the invention

[0004] The purpose of the present invention is to provide a blowout inducing valve for testing high-pressure oil and gas wells, which solves the problems that it is difficult to induce blowout successfully using conventional oil testing processes, accidents are prone to occur when using negative pressure to induce blowout, and it is difficult to achieve switching using the switch valve of the test tool itself when the pressure difference is large.

[0005] To this end, the technical solution of the present invention is as follows:

[0006] A blowout inducement valve for testing high-pressure oil and gas wells, comprising a main pipeline, a sliding pipe, a trapezoidal stopper, a stamping plate, a telescopic spring assembly, a flow limiting rod, a drainage pipe and a connecting joint; wherein the sliding pipe, the trapezoidal stopper and the flow limiting rod are sequentially connected from top to bottom and coaxially arranged in the main pipeline; a first connecting ring and a second connecting ring are arranged and fixed on the inner wall of the main pipeline from top to bottom at intervals; the trapezoidal stopper is inserted in the first connecting ring to divide the inner cavity of the main pipeline into two parts; the stamping plate is sleeved and fixed on the outer wall of the sliding pipe located above the first connecting ring, and the telescopic spring assembly is arranged between the stamping plate and the first connecting ring, so that the stamping plate can move downward by compressing the telescopic spring assembly; on the upper outer wall of the flow limiting rod An annular flow limiting block is provided, which is arranged in the main pipeline in a manner of having a gap; the drainage tube is a cylinder with an opening at the top and a closed bottom, which is sleeved on the outer side of the lower part of the flow limiting rod in a manner of having a gap; the outer wall of the top end of the drainage tube is fixed on the inner wall of the second connecting ring, and a plurality of drainage holes are evenly distributed along the circumferential direction on the side wall of the bottom end; a through hole is provided in the center of the connecting joint, which is sleeved on the outside of the sliding tube and fixed at the top opening of the main pipeline; two pressure transmission hole groups are symmetrically provided on the side wall of the main pipeline located above the stamping plate, and each pressure transmission hole group is composed of a plurality of pressure transmission holes concentrated on the side wall of the main pipeline; at least two rows of diversion hole groups are provided on the side wall of the bottom end of the sliding tube.

[0007] Furthermore, the telescopic spring assembly is composed of four telescopic springs evenly distributed along the circumferential direction of the sliding tube; two ends of each telescopic spring are respectively fixed on the bottom surface of the stamping plate and the top surface of the first connecting ring.

[0008] Furthermore, the upper inner diameter of the first connecting ring is smaller than the lower inner diameter and the inner wall at the diameter change point is a conical surface; the trapezoidal limit block is composed of an upper trapezoidal platform and a lower cylindrical body, and its shape and size are consistent with the shape and size of the diameter change point and the lower part of the first connecting ring, so that the trapezoidal limit block is sealed in the first connecting ring.

[0009] Furthermore, an annular sealing groove is respectively provided on the conical inner wall and the lower inner wall of the first connecting ring, and a first sealing ring is arranged in each annular sealing groove, so that a seal is formed between the trapezoidal limit block and the first connecting ring through the two first sealing rings.

[0010] Furthermore, the outer diameter of the stamping plate is adapted to the inner diameter of the main pipe, and a lap rubber ring is sleeved and fixed on the annular outer wall thereof, so that a seal is formed between the stamping plate and the main pipe.

[0011] Furthermore, each row of guide holes is composed of a plurality of guide holes evenly distributed along the circumferential direction, and the guide holes on the two rows of guide hole groups are staggered.

[0012] Furthermore, the through hole in the center of the connecting joint is adapted to the outer diameter of the sliding tube, and two sliding tube sealing rings are arranged on the inner wall thereof, so as to form a seal between the sliding tube and the connecting joint.

[0013] Compared with the existing technology, the blowout induced valve for high-pressure oil and gas well testing has a simple structure, easy operation, high stability and strong reliability. It is particularly suitable for use in gas wells with high formation pressure. It can operate stably under high temperature and high pressure, and can effectively control the speed at which formation products flow into the wellbore. It can realize the blowout induced function while ensuring the safety of well control, and has great market application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a front cross-sectional structural schematic diagram of a blowout inducing valve for testing a high-pressure oil and gas well according to the present invention;

[0015] Figure 2 for Figure 1 A schematic diagram of the partially enlarged structure at point A in the middle;

[0016] Figure 3 It is a schematic structural diagram of the blowout inducement valve for testing high-pressure oil and gas wells of the present invention in use. DETAILED DESCRIPTION

[0017] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but the following embodiments are by no means intended to limit the present invention in any way.

[0018] like Figure 1 and Figure 2 As shown, the blowout inducing valve for testing high-pressure oil and gas wells comprises a main pipeline 1, a sliding pipe 4, a trapezoidal stopper 5, a stamping plate 7, a telescopic spring assembly, a flow limiting rod 10, a drainage pipe 11 and a connecting joint 12;

[0019] The main pipe 1 is a cylindrical body, on the inner wall of which a first connecting ring 2 and a second connecting ring 3 are arranged and fixed at intervals from top to bottom; specifically, the first connecting ring 2 is arranged near the top of the main pipe 1, the inner diameter of the upper part is smaller than the inner diameter of the lower part, and the inner wall at the diameter change is a conical surface; an annular sealing groove is respectively opened on the conical inner wall and the lower inner wall of the first connecting ring 2, and a first sealing ring 6 is arranged in each annular sealing groove;

[0020] The sliding pipe 4, the trapezoidal stopper 5 and the flow limiting rod 10 are sequentially arranged in the main pipeline 1 from top to bottom, and the three are coaxially arranged; specifically,

[0021] The trapezoidal stopper 5 is composed of an upper trapezoidal platform and a lower cylindrical body, and its shape and size are consistent with the shape and size of the inner diameter reducing part and the lower part of the first connecting ring 2, so that the trapezoidal stopper 5 and the first connecting ring 2 are sealed through two first sealing rings 6;

[0022] The sliding tube 4 is a cylindrical tube body, the bottom end of which is inserted into the upper part of the first connecting ring 2, and the end face of the bottom end is fixed on the top end face of the trapezoidal limit block 5; two rows of guide hole groups are spaced apart on the side wall of the bottom end of the sliding tube 4, each row of guide hole groups is composed of six guide holes 15 evenly distributed along the circumferential direction, and the guide holes 15 on the two rows of guide hole groups are staggered; the aperture of the guide hole 15 is 10 mm.

[0023] The stamping plate 7 is a circular plate with a through hole in the center, so that it is mounted and fixed on the outer wall of the sliding tube 4 located above the first connecting ring 2; the outer diameter of the stamping plate 7 is adapted to the inner diameter of the main pipeline 1, and a lap rubber ring 13 is mounted and fixed on its annular outer wall to form a seal between the stamping plate 7 and the main pipeline 1. At this time, the stamping plate 7, the first connecting ring 2 and the main pipe column 1 form a first chamber A; two pressure transmission hole groups 14 are symmetrically opened on the side wall of the main pipeline 1 located above the stamping plate 7, and each pressure transmission hole group 14 is composed of seven pressure transmission holes with a hole diameter of 4 mm concentrated on the side wall of the main pipeline 1; each pressure transmission hole is a pressure transmission hole 14 connected to the first chamber A;

[0024] The telescopic spring assembly is arranged between the stamping plate 7 and the first connecting ring 2, and is composed of four telescopic springs 8 evenly arranged along the circumferential direction of the sliding tube 4; the two ends of each telescopic spring 8 are respectively fixed on the bottom surface of the stamping plate 7 and the top surface of the first connecting ring 2;

[0025] The flow limiting rod 10 is a cylindrical rod body, and its top end face is fixed on the bottom end face of the trapezoidal limiting block 5; an annular flow limiting block 9 is provided on the upper outer wall of the flow limiting rod 10, and its outer diameter is slightly smaller than the inner diameter of the main pipe 1, so that the flow limiting block 9 is arranged in the main pipe 1 in a gap manner;

[0026] The drainage tube 11 is a cylinder with an opening at the top and a closed bottom, which is sleeved on the outer side of the lower part of the flow limiting rod 10 in a gap-like manner; the top outer wall of the drainage tube 11 is fixed on the inner wall of the second connecting ring 3, and the bottom side wall is evenly distributed along the circumferential direction with six drainage holes 11a, each of which has a diameter of 12 mm;

[0027] The bottom end of the connecting joint 12 is threadedly fixed on the inner wall of the top end of the main pipeline 1, and its top end is used to form a connection with the oil pipe above; a through hole adapted to the outer diameter of the sliding tube 4 is opened in the center of the connecting joint 12, and two sliding tube sealing rings 16 are provided on its inner wall to form a seal between the sliding tube 4 and the connecting joint 12, so that the stamping plate 7 can always be kept in a sealed state with the connecting joint 12 during the up and down movement of the sliding tube 4 relative to the connecting joint 12.

[0028] The working principle of the blowout induced valve for high-pressure oil and gas well testing is as follows:

[0029] When in use, the bottom end of the high-pressure oil and gas well test induced blowout valve is first connected to the packer and the screen pipe, and the top end is connected to the oil pipe to form an induced blowout pipe string; the induced blowout pipe string is sent into the well to a preset depth and the packer is set on the inner wall of the casing;

[0030] like Figure 3 As shown, the pump truck pressurizes the annulus between the oil pipe and the casing through the ground well-killing manifold P1, and the high-pressure liquid enters the first chamber A through the pressure transmission hole 14 to exert pressure on the stamping plate 7, pushing the stamping plate 7 to drive the sliding tube 4 to move downward together and compress the telescopic spring 8 until the four telescopic springs 8 are completely compressed; at this time, the sliding tube 4 simultaneously pushes the trapezoidal limit block 5 and the flow limiting rod 10 to move downward together during the downward movement; wherein, the trapezoidal limit block 5 gradually separates from the first connecting ring 2 during the downward movement, so that an annular oil and gas channel is formed between the first connecting ring 2 and the sliding tube 4; the flow limiting rod 10 moves downward until it is close to the top surface of the second connecting ring;

[0031] Since the oil and gas channel is open, the liquid carrying oil at the bottom of the well enters the main pipeline 1 under the action of the formation pressure, and then enters the drainage pipe 11 through the drainage hole 11a and goes up to the second chamber B surrounded by the first connecting ring 2, the second connecting ring 3 and the main pipeline 1. Since the second chamber B is divided by the flow limiting rod 10 and the flow limiting block 9 into an upper chamber and a lower chamber connected by a small annular channel, and the volume of the lower chamber is smaller than that of the upper chamber, the flow rate of the bottom hole liquid gradually slows down during the process of flowing from the lower chamber to the upper chamber under the action of flow limiting, so as to avoid the impact of the liquid pressure on the upper components;

[0032] As the sliding tube 4 moves downward, the two rows of diversion holes on it are connected with the upper chamber, so that the formation liquid entering the upper chamber enters the tube body of the sliding tube 4 through the diversion holes 15 until it reaches the top end of the sliding tube 4 and is finally discharged into the liquid collecting tank on the ground.

[0033] When the pressure of the pump truck is released, the four telescopic springs 8 rebound under the action of elastic force, push the stamping plate 7 and drive the sliding tube 4, push the trapezoidal limit block 5 and the flow limiting rod 10 to move upward to the original position synchronously, then the oil and gas channel is closed, and the liquid carrying oil at the bottom of the well stops rushing out.

[0034] The blowout induced valve for high-pressure oil and gas well testing has been shown in actual field applications to have strong resistance to high temperature and high pressure, and is suitable for the early stages of oil field exploration and development, especially for gas wells with high formation pressure.

[0035] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions only describe the principles of the present invention. The present invention may be subject to various changes and improvements without departing from the spirit and scope of the present invention. These changes and improvements fall within the scope of the present invention. The scope of protection claimed by the present invention is defined by the attached claims and their equivalents.

Claims

1. A blowout inducing valve for testing high-pressure oil and gas wells, characterized in that: The invention comprises a main pipeline (1), a sliding pipe (4), a trapezoidal stop block (5), a stamping plate (7), a telescopic spring assembly, a flow limiting rod (10), a drainage pipe (11) and a connecting joint (12); wherein the sliding pipe (4), the trapezoidal stop block (5) and the flow limiting rod (10) are sequentially connected from top to bottom and coaxially arranged in the main pipeline (1); a first connecting ring (2) and a second connecting ring (3) are arranged and fixed on the inner wall of the main pipeline (1) at intervals from top to bottom; the trapezoidal stop block (5) is inserted into the main pipeline (11); and the first connecting ring (2) and the second connecting ring (3) are arranged and fixed on the inner wall of the main pipeline (1) at intervals from top to bottom. In the first connecting ring (2), the inner cavity of the main pipeline (1) is divided into two parts; the stamping plate (7) is mounted on and fixed to the outer wall of the sliding tube (4) located above the first connecting ring (2); the telescopic spring assembly is arranged between the stamping plate (7) and the first connecting ring (2), so that the stamping plate (7) can move downward by compressing the telescopic spring assembly; an annular flow limiting block (9) is arranged on the upper outer wall of the flow limiting rod (10); the annular flow limiting block (9) is arranged in the main pipeline (1) in a manner of having a gap. The drainage tube (11) is a cylindrical body with an opening at the top and a closed bottom, and is sleeved on the outer side of the lower part of the flow limiting rod (10) in a gap-like manner; the outer wall of the top end of the drainage tube (11) is fixed to the inner wall of the second connecting ring (3), and a plurality of drainage holes (11a) are evenly distributed along the circumferential direction on the side wall of the bottom end; a through hole is opened in the center of the connecting joint (12), which is sleeved on the outside of the sliding tube (4) and fixed at the top opening of the main pipeline (1); at the top of the stamping plate (7), the outer wall of the drainage tube (11) is fixed to the inner wall of the second connecting ring (3), and a plurality of drainage holes (11a) are evenly distributed along the circumferential direction on the side wall of the bottom end; a through hole is opened in the center of the connecting joint (12), which is sleeved on the outside of the sliding tube (4) and fixed at the top opening of the main pipeline (1); Two pressure transmission hole groups (14) are symmetrically provided on the side wall of the main pipe (1), and each pressure transmission hole group (14) is composed of a plurality of pressure transmission holes concentrated on the side wall of the main pipe (1); at least two rows of flow guide hole groups are provided on the side wall of the bottom end of the sliding pipe (4); the telescopic spring assembly is composed of four telescopic springs (8) evenly distributed along the circumferential direction of the sliding pipe (4); and the two ends of each telescopic spring (8) are respectively fixed on the bottom surface of the stamping plate (7) and the top surface of the first connecting ring (2).

2. The blowout inducement valve for high-pressure oil and gas well testing according to claim 1 is characterized in that: The upper inner diameter of the first connecting ring (2) is smaller than the lower inner diameter, and the inner wall of the diameter change portion is a conical surface; the trapezoidal stopper (5) is composed of an upper trapezoidal platform and a lower columnar body, and its shape and size are consistent with the shape and size of the diameter change portion and the lower portion of the first connecting ring (2), so that the trapezoidal stopper (5) is sealed in the first connecting ring (2).

3. The blowout inducing valve for high-pressure oil and gas well testing according to claim 2 is characterized in that: An annular sealing groove is respectively provided on the conical inner wall and the lower inner wall of the first connecting ring (2), and a first sealing ring (6) is arranged in each annular sealing groove, so that a seal is formed between the trapezoidal limit block (5) and the first connecting ring (2) through the two first sealing rings (6).

4. The blowout inducing valve for high-pressure oil and gas well testing according to claim 1 is characterized in that: The outer diameter of the stamping plate (7) is adapted to the inner diameter of the main pipe (1), and a lap rubber ring (13) is mounted and fixed on its annular outer wall to form a seal between the stamping plate (7) and the main pipe (1).

5. The blowout inducing valve for testing high-pressure oil and gas wells according to claim 1 is characterized in that: Each row of flow guide groups is composed of a plurality of flow guide holes (15) evenly distributed along the circumferential direction, and the flow guide holes (15) on the two rows of flow guide hole groups are arranged in a staggered manner.

6. The blowout inducing valve for testing high-pressure oil and gas wells according to claim 1, characterized in that: The through hole in the center of the connecting joint (12) is adapted to the outer diameter of the sliding tube (4), and two sliding tube sealing rings (16) are arranged on the inner wall thereof to form a seal between the sliding tube (4) and the connecting joint (12).

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