Flange nipple for oil well blowout

Abstract

The utility model provides a flange short section for oil well blowout, which is used for being connected between an oil nozzle manifold at a wellhead and an oil nozzle manifold at a blowout position, and comprises a first flange, a second flange and an outer pipe connected between the first flange and the second flange, an inner pipe is assembled in an inner cavity of the outer pipe, and the inner pipe is connected with the first flange and the second flange. An annular wall clamping cavity is formed between the outer pipe and the inner pipe; wherein the inlet end of the inner pipe is connected with a puncture-proof sleeve, the inner pipe comprises a punching screen pipe arranged close to the puncture-proof sleeve, and the inner pipe further comprises a slotted screen pipe arranged at the outlet end of the inner pipe. The anti-stabbing oil nozzle has the advantages that oil-gas fluid can be depressurized through the anti-stabbing sleeve, impurities in the oil-gas fluid can be collected through the annular clamping wall cavity, and a blowout pipeline can be prevented from being stabbed to be damaged, and the oil nozzle can be prevented from being blocked.

Description

Technical Field

[0001] The utility model relates to the technical field of oil and gas field drilling and development, in particular to a flange short joint for oil well blowout, which is especially suitable for shale oil well blowout. Background Art

[0002] During the on-site construction of shale oil wells, continuous tubing equipment and supporting tools are required for high-pressure blowdown and drilling plug construction after fracturing. Due to the high pressure in the well, the high-flow blowdown fluid carries a large amount of sand and bridge plug debris during construction, which often punctures the thread and body of the buffer short section at the rear end of the nozzle manifold, posing a safety hazard and affecting normal construction. In addition, there is a risk of injury during the replacement of the buffer short section, which will increase the construction cost; the well needs to be shut down during replacement, and the sand and debris in the annulus of the well are easy to settle, which can easily cause the drill to get stuck, and there are great risks in the operation and construction.

[0003] During normal blowout, the oil and gas flow in the well will bring out the formation sand and soluble bridge plug debris. Since the blowout nozzle installed in the nozzle manifold has a small aperture, it is very easy to cause blockage. When blocked, the wellhead gate needs to be closed and the nozzle manifold needs to be flushed with clean water to remove the sand. During the well shut-in period, the pressure in the well continues to rise, affecting the production capacity, and the construction risk is high when the well is reopened.

[0004] Therefore, it is necessary to study a flange nipple for oil well blowout to solve the above problems or alleviate the impact of the above problems. Utility Model Content

[0005] The utility model provides a flange short joint for oil well blowout, which can reduce the pressure of oil and gas fluid through a puncture-proof sleeve, collect impurities in the oil and gas fluid through an annular clamping wall cavity, and prevent the blowout pipeline from being punctured and the oil nozzle from being blocked, so as to effectively solve the above problems or alleviate the effects of the above problems.

[0006] The utility model of the flange nipple for oil well blowout is used to connect between the oil nozzle manifold at the wellhead and the oil nozzle manifold at the blowout location. The flange nipple comprises a first flange, a second flange and an outer pipe connected between the first flange and the second flange. The inner cavity of the outer pipe is equipped with an inner pipe, and an annular sandwich wall cavity is formed between the outer pipe and the inner pipe.

[0007] Among them, the inner tube is connected to a stab-proof sleeve at its inlet end, and the stab-proof sleeve is used to reduce the pressure of the oil and gas fluid; the inner tube includes a perforated screen tube arranged close to the stab-proof sleeve, and the perforated screen tube is used to pass the oil and gas fluid into the annular sandwich wall cavity; the inner tube also includes a slit screen tube arranged at its outlet end, and the slit screen tube is used to prevent impurities in the oil and gas fluid from flowing back into the inner cavity of the inner tube.

[0008] In one embodiment, the stab-proof sleeve is a cylindrical structure, and its outer diameter is consistent with the inner diameter of the inner tube, so that it is partially inserted into the inner tube. The inner cavity of the stab-proof sleeve is a variable diameter channel, and the inner diameter of the stab-proof sleeve located in the inner tube is larger than the inner diameter located outside the inner tube.

[0009] In one embodiment, a radially extending annular convex plate is provided at a middle position of the outer side of the stab-proof sleeve, and the annular convex plate is used to seal one end of the annular sandwich wall cavity located at the first flange.

[0010] In one embodiment, the wall of the perforated screen pipe is provided with a plurality of first through holes penetrating radially thereof, and the size of the first through holes is larger than the size of impurities in the oil and gas fluid.

[0011] In one embodiment, the pipe wall of the slotted screen pipe is provided with a plurality of second through holes penetrating in the radial direction thereof, and the size of the second through holes is smaller than the size of impurities in the oil and gas fluid.

[0012] In one embodiment, a gland is fixedly connected between the outer tube and the inner tube, and the gland is used to seal one end of the annular sandwich cavity located at the second flange.

[0013] In one embodiment, the inner tube is provided with an annular groove on the outer wall of the inlet end thereof, and the annular groove is used to install a rubber ring, and the rubber ring is annular and can fit tightly with the inner wall of the outer tube.

[0014] In one embodiment, a magnetic attraction component is fixedly provided on the outer wall of the inner tube, and the magnetic attraction component can absorb ferromagnetic impurities.

[0015] In one embodiment, the inner walls of the first flange and the second flange are both provided with internal threads, and both ends of the outer tube are both provided with external threads matching the internal threads.

[0016] In one embodiment, the first flange and the second flange are both provided with threaded holes for connection and steel ring grooves for assembling steel rings.

[0017] The utility model provides a flange short joint for oil well blowout, which has at least the following beneficial effects compared with the prior art:

[0018] The utility model of the flange nipple for oil well blowout can reduce the pressure of oil and gas fluid through the anti-puncture sleeve, and can collect impurities in the oil and gas fluid through the annular clamping wall cavity, which can prevent the blowout pipe line from being punctured and the oil nozzle from being blocked. In this way, when the flange nipple is used for blowout after shale oil well fracturing and pressure drilling plug operation, it can prevent high-pressure liquid and sand particles and debris from puncturing the ground blowout pipe line, playing a protective role. At the same time, during operation and blowout, it can collect impurities such as sand and bridge plug debris ejected from the well, prevent the oil nozzle of the high-pressure manifold from being blocked, and extend production time. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention will be described in more detail below based on embodiments and with reference to the accompanying drawings.

[0020] Figure 1 The utility model is a structural schematic diagram of a flange short joint for oil well blowout according to an embodiment of the utility model.

[0021] In the drawings, the same reference numerals are used for the same components. The drawings are not drawn to scale.

[0022] Reference numerals:

[0023] 1-first flange, 2-second flange, 3-outer tube, 4-inner tube, 5-stab-proof sleeve, 6-perforated screen tube, 7-slit screen tube, 8-annular convex plate, 9-pressure cover, 10-rubber ring, 11-magnetic suction part, 12-threaded hole, 13-steel ring groove. DETAILED DESCRIPTION

[0024] The utility model will be further described below in conjunction with the accompanying drawings.

[0025] like Figure 1 As shown, the flange nipple for oil well blowout of the utility model is used to connect between the nozzle manifold at the wellhead and the nozzle manifold at the blowout location, and the flange nipple comprises a first flange 1, a second flange 2, and an outer tube 3 connected between the first flange 1 and the second flange 2, the inner cavity of the outer tube 3 is equipped with an inner tube 4, and an annular sandwich wall cavity is formed between the outer tube 3 and the inner tube 4;

[0026] Among them, the inner tube 4 is connected to a stab-proof sleeve 5 at its inlet end, and the stab-proof sleeve 5 is used to reduce the pressure of the oil and gas fluid; the inner tube 4 includes a perforated screen tube 6 arranged near the stab-proof sleeve 5, and the perforated screen tube 6 is used to pass the oil and gas fluid into the annular clamped wall cavity; the inner tube 4 also includes a slit screen tube 7 arranged at its outlet end, and the slit screen tube 7 is used to prevent impurities in the oil and gas fluid from flowing back into the inner cavity of the inner tube 4.

[0027] Specifically, the flange nipple is connected to the flange of the nozzle manifold at the wellhead through the first flange 1, and is connected to the flange of the nozzle manifold at the blowout location through the second flange 2, and at the same time, the two ends of the inner tube 4 are connected to the nozzle manifold at the wellhead and the nozzle manifold at the blowout location, respectively, so that the oil and gas fluid flows from the nozzle manifold at the wellhead through the inner tube 4 and then flows into the nozzle manifold at the blowout location. The central axis of the inner tube 4 and the outer tube 3 are the same, that is, the end faces of the two are concentric circles with different radii, and an annular sandwich wall cavity for collecting impurities is formed between the outer tube 3 and the inner tube 4. The provision of the anti-puncture sleeve 5 can reduce the pressure of the oil and gas fluid, and the perforated screen tube 6 connects the inner cavity of the inner tube 4 with the annular sandwich wall cavity, so that the oil and gas fluid can flow from the inner cavity of the inner tube 4 into the annular sandwich wall cavity with impurities, and the slit screen tube 7 can prevent impurities in the oil and gas fluid from flowing back to the inner cavity of the inner tube 4, so that the impurities in the oil and gas fluid remain in the annular sandwich wall cavity.

[0028] If necessary, please attach Figure 1 The upper end of the middle flange short section is the inlet end of the inner tube 4 , that is, the position of the first flange 1 , and the lower end of the flange short section is the outlet end of the inner tube 4 , that is, the position of the second flange 2 .

[0029] In general, the flange nipple for oil well blowout can reduce the pressure of oil and gas fluid through the puncture-proof sleeve 5, and can collect impurities in the oil and gas fluid through the annular clamping wall cavity, which can prevent the blowout pipe line from being punctured and the oil nozzle from being blocked. In this way, when the flange nipple is used for blowout after shale oil well fracturing and pressure drilling plug operation, it can prevent high-pressure liquid, sand particles, and debris from puncturing the ground blowout pipe line, playing a protective role. At the same time, during operation and blowout, it can collect impurities such as sand and bridge plug debris ejected from the well, prevent the oil nozzle of the high-pressure manifold at the blowout location from being blocked, and extend production time.

[0030] In one example, the stab-proof sleeve 5 is a cylindrical structure, and its outer diameter is consistent with the inner diameter of the inner tube 4, so that it is partially inserted into the inner tube 4, and the inner cavity of the stab-proof sleeve 5 is a variable diameter channel, and the inner diameter of the stab-proof sleeve 5 located in the inner tube 4 is larger than the inner diameter located outside the inner tube 4.

[0031] Specifically, the outer diameter of the stab-proof sleeve 5 is consistent with the inner diameter of the inner tube 4, so that it can be completely matched and assembled in the inner cavity of the inner tube 4 by plugging. The inner diameter of the stab-proof sleeve 5 can gradually increase with the flow direction of the oil and gas fluid, so that the oil and gas fluid pressure is gradually reduced, and the oil and gas fluid has a radial diffusion flow drive, so that part of the oil and gas fluid reaches the perforated screen 6 and smoothly enters the annular sandwich wall cavity. It should be noted that the inner diameter of the upper end of the stab-proof sleeve 5 (located outside the inner tube 4) must meet the requirement of covering the oil nozzle in the oil nozzle manifold at the wellhead.

[0032] In one example, a radially extending annular convex plate 8 is provided at the middle position of the outer side of the stab-proof sleeve 5 , and the annular convex plate 8 is used to seal one end of the annular sandwich wall cavity located at the first flange 1 .

[0033] Specifically, the area of ​​the annular convex plate 8 on the outside of the stab-proof sleeve 5 is not less than the end surface area of ​​the annular sandwich wall cavity, and the annular convex plate 8 can fit with the end surfaces of the inner tube 4 and the outer tube 3 to close the upper end of the annular sandwich wall cavity. It should be noted that after the flange nipple is connected to the nozzle manifold at the wellhead, the annular convex plate 8 will be tightly pressed against the ends of the inner tube 4 and the outer tube 3 under the action of the connecting end of the nozzle manifold at the wellhead to ensure the closure of the upper end of the annular sandwich wall cavity. And the lower end of the annular convex plate 8 can also fit tightly with the upper end of the first flange 1 to play a limiting role.

[0034] In one example, the wall of the perforated screen tube 6 is provided with a plurality of first through holes penetrating in the radial direction thereof, and the size of the first through holes is larger than the size of impurities in the oil and gas fluid.

[0035] Specifically, the first through hole can be a circular hole. A plurality of first through holes can be evenly distributed along the circumference of the perforated screen tube 6 and evenly distributed along its axial direction. The size of the first through hole needs to be larger than the size of impurities in the oil and gas fluid, so that the oil and gas fluid can carry the impurities into the annular sandwich wall cavity, providing a source for the annular sandwich wall cavity to collect impurities.

[0036] In one example, the pipe wall of the slotted screen pipe 7 is provided with a plurality of second through holes penetrating in the radial direction thereof, and the size of the second through holes is smaller than the size of impurities in the oil and gas fluid.

[0037] Specifically, the second through hole can be a long hole or a strip-shaped gap. The plurality of second through holes can be evenly distributed along the circumference of the slotted screen tube 7 and also evenly distributed along its axial direction. The size of the second through hole needs to be smaller than the size of the impurities in the oil and gas fluid, so that the slotted screen tube 7 can pass the oil and gas fluid while blocking the passage of the impurities in the oil and gas fluid, so that the impurities in the annular sandwich wall cavity cannot flow back to the inner cavity of the inner tube 4 and form aggregation, thereby achieving the purpose of collecting impurities in the oil and gas fluid.

[0038] It should be noted that the sizes of the first through hole and the second through hole can be set according to the specific conditions of impurities in the oil and gas fluid on site.

[0039] In one example, a gland 9 is fixedly connected between the outer tube 3 and the inner tube 4 , and the gland 9 is used to seal one end of the annular sandwich cavity located at the second flange 2 .

[0040] Specifically, the gland 9 is an annular structure and is fixedly arranged at one end of the annular sandwich wall cavity located at the second flange 2. The inner side of the gland 9 is fixedly welded to the outside of the inner tube 4, the outer side of the gland 9 is provided with an external thread, and the inner side of the outer tube 3 is provided with an internal thread matching therewith, and the gland 9 is fixedly connected with the outer tube 3 through thread matching. In this way, the gland 9 can not only block the lower end of the annular sandwich wall cavity, but also the outer tube 3 can support and fix the inner tube 4 through the gland 9, thereby ensuring the structural stability of the flange short section.

[0041] In one example, an annular groove is formed on the outer wall of the inlet end of the inner tube 4 , and the annular groove is used to install the rubber ring 10 . The rubber ring 10 is annular and can fit tightly with the inner wall of the outer tube 3 .

[0042] Specifically, the outer wall of the inner tube 4 can match the rubber ring 10 through the annular groove, so that the inner and outer rings of the rubber ring 10 are tightly fitted with the outer wall of the inner tube 4 and the inner wall of the outer tube 3 respectively, which can support and fix the inner tube 4 and further improve the sealing performance of the upper end of the annular clamping wall cavity.

[0043] In one example, a magnetic attraction member 11 is fixedly provided on the outer wall of the inner tube 4, and the magnetic attraction member 11 can absorb ferromagnetic impurities. The magnetic attraction member 11 can be installed at the lower end of the inner tube 4 by a pin, and can effectively absorb ferromagnetic debris in the oil and gas fluid.

[0044] In one example, the inner walls of the first flange 1 and the second flange 2 are both provided with internal threads, and both ends of the outer tube 3 are both provided with external threads matching the internal threads. The first flange 1 and the second flange 2 are both fixedly connected to both ends of the outer tube 3 by threaded matching.

[0045] In one example, both the first flange 1 and the second flange 2 are provided with threaded holes 12 for connection and steel ring grooves 13 for assembling steel rings.

[0046] Specifically, the bodies of the first flange 1 and the second flange 2 are provided with threaded holes 12 that penetrate from top to bottom, and the matching bolts can be fixedly connected with the flanges of the nozzle manifold at the wellhead and the nozzle manifold at the blowout, respectively. The inner sides of the first flange 1 and the second flange 2 are provided with steel ring grooves 13, and the matching steel rings can improve the sealing of the connection when connected with the nozzle manifold at the wellhead and the nozzle manifold at the blowout, so as to prevent the oil and gas fluid from spraying out from the connection.

[0047] In order to better understand the present invention, the process of applying the flange nipple to the pressure drilling or blowout operation of a shale oil well is further described in conjunction with the accompanying drawings.

[0048] When the shale oil well needs to be drilled or blown out after fracturing, first install the steel ring in the steel ring groove 13 of the first flange 1, and connect the first flange 1 to the flange of the nozzle manifold at the wellhead by bolts. After the connection is completed, the upper end of the puncture-proof sleeve 5 can cover the nozzle in the nozzle manifold. At the same time, connect the second flange 2 to the ordinary buffer nipple until it is connected to the nozzle manifold at the blowout location (it can also be directly connected to the flange of the nozzle manifold at the blowout location).

[0049] During normal pressure drilling or blowout, the wellhead gate is opened, and the high-pressure oil and gas in the well pass through the oil nozzle in the oil nozzle manifold at the wellhead, through the puncture-proof sleeve 5 and the inner cavity of the flange short section to the oil nozzle manifold at the blowout. The puncture-proof sleeve 5 can isolate the upper wellhead connection thread of the flange short section from the high-pressure oil and gas, and can prevent the sand and debris carried by the high-pressure oil and gas from piercing the weak connection parts. The lower diameter of the puncture-proof sleeve 5 is larger than the upper diameter, which can relieve the pressure of the high-pressure oil and gas flow. Part of the oil and gas can carry impurities such as sand and metal debris in the well through the perforated screen tube 6 into the annular sandwich wall cavity between the inner tube 4 and the outer tube 3, and then the oil and gas will flow back to the inner cavity of the inner tube 4 through the slit screen tube 7. During this flow process, due to the large size of the first through hole of the perforated screen tube 6, impurities can enter the annular sandwich wall cavity, and due to the small size of the second through hole of the slit screen tube 7, it can effectively prevent impurities from flowing back into the inner cavity of the inner tube 4 and gather in the annular sandwich wall cavity of the inner tube 4 and the outer tube 3; the magnetic suction piece 11 fixed to the inner tube 4 by pins can also effectively absorb ferromagnetic debris. The rubber ring 10 is installed in the annular groove at the upper end of the inner tube 4 and fits tightly with the inner wall of the outer tube 3, which can fix the inner tube 4 and reduce shock. After long-term use, the wellhead gate is closed, the anti-puncture sleeve 5 can be replaced, and after cleaning the impurities in the annular sandwich wall cavity, it can be installed again for reuse.

[0050] In this way, when the shale oil well is blown out, the connection threads can be effectively protected to prevent them from being pierced by sand particles carried by the oil and gas flow. Sand and bridge plug debris sprayed out of the well can be collected to prevent the high-pressure manifold nozzle from being blocked, thereby extending the production time.

[0051] In summary, the beneficial effects of the flange nipple for oil well blowout of the utility model include:

[0052] The flange nipple can effectively protect the connecting threads and body parts near the wellhead, prolonging the service life. The replacement of the puncture-proof sleeve is simple and low-cost. At the same time, it can collect sand and debris sprayed out of the well, effectively avoiding the blockage of the nozzle in the nozzle manifold at the spraying point, thereby improving production efficiency.

[0053] Although the present invention has been described with reference to preferred embodiments, various modifications may be made thereto and parts thereof may be replaced with equivalents without departing from the scope of the present invention. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there is no structural conflict. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A flange nipple for oil well blowout, used to connect between the nozzle manifold at the wellhead and the nozzle manifold at the blowout location, characterized in that: The flange nipple comprises a first flange, a second flange and an outer tube connected between the first flange and the second flange, the inner cavity of the outer tube is equipped with an inner tube, and an annular sandwich wall cavity is formed between the outer tube and the inner tube; Among them, the inner tube is connected to a stab-proof sleeve at its inlet end, and the stab-proof sleeve is used to reduce the pressure of the oil and gas fluid; the inner tube includes a perforated screen tube arranged close to the stab-proof sleeve, and the perforated screen tube is used to pass the oil and gas fluid into the annular sandwich wall cavity; the inner tube also includes a slit screen tube arranged at its outlet end, and the slit screen tube is used to prevent impurities in the oil and gas fluid from flowing back into the inner cavity of the inner tube.

2. The flange nipple for oil well blowout according to claim 1 is characterized in that: The stab-proof sleeve is a cylindrical structure, and its outer diameter is consistent with the inner diameter of the inner tube, so that it is partially sleeved in the inner tube. The inner cavity of the stab-proof sleeve is a variable diameter channel, and the inner diameter of the stab-proof sleeve located in the inner tube is larger than the inner diameter located outside the inner tube.

3. The flange nipple for oil well blowout according to claim 2 is characterized in that: A radially extending annular convex plate is provided at the middle position of the outer side of the stab-proof sleeve, and the annular convex plate is used to block one end of the annular clamping wall cavity located at the first flange.

4. The flange nipple for oil well blowout according to claim 1, characterized in that: The wall of the perforated screen tube is provided with a plurality of first through holes penetrating in the radial direction thereof, and the size of the first through holes is larger than the size of impurities in the oil and gas fluid.

5. The flange nipple for oil well blowout according to claim 1, characterized in that: The pipe wall of the slotted screen pipe is provided with a plurality of second through holes penetrating in the radial direction thereof, and the size of the second through holes is smaller than the size of impurities in the oil and gas fluid.

6. The flange nipple for oil well blowout according to any one of claims 1 to 5, characterized in that: A gland is fixedly connected between the outer tube and the inner tube, and the gland is used to seal one end of the annular sandwich wall cavity located at the second flange.

7. The flange nipple for oil well blowout according to any one of claims 1 to 5, characterized in that: The inner tube has an annular groove on its outer wall at the inlet end. The annular groove is used to install a rubber ring. The rubber ring has an annular structure and can fit tightly with the inner wall of the outer tube.

8. The flange nipple for oil well blowout according to any one of claims 1 to 5, characterized in that: A magnetic attraction component is fixedly provided on the outer wall of the inner tube, and the magnetic attraction component can absorb ferromagnetic impurities.

9. The flange nipple for oil well blowout according to any one of claims 1 to 5, characterized in that: The inner walls of the first flange and the second flange are both provided with internal threads, and both ends of the outer tube are both provided with external threads matching the internal threads.

10. The flange nipple for oil well blowout according to any one of claims 1 to 5, characterized in that: The first flange and the second flange are both provided with threaded holes for connection and steel ring grooves for assembling steel rings.

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