Gas production wellhead

Abstract

The invention provides a gas production well mouth which comprises an integral valve group, a gas production well mouth and a gas production well mouth. One end of the main passage is connected with one connecting port; the oil pipe head is connected with the main passage and is provided with an oil pipe; the connector is connected with the oil pipe head, a central through hole of the connector is divided into a first hole section and a second hole section which are different in inner diameter, a pipe opening of the oil pipe extends into the second hole section from an opening of the first hole section, and an opening of the second hole section is used for extending into a sleeve; the adaptive ring is arranged in the second hole section in a replaceable mode, the adaptive ring is provided with an adaptive hole, and the hole diameter of the adaptive hole is matched with the outer diameter of the oil pipe and the outer diameter of the sleeve so that the oil pipe and the sleeve can be fixed in the adaptive ring; the annular sealing element is propped against one side, far away from the step surface, of the adaptive ring; the fixing ring is arranged on the side, away from the adaptive ring, of the annular sealing piece. The problem that in the prior art, the adaptability of a gas production wellhead and a sleeve is poor is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of oil and gas development, and in particular to a gas production wellhead. Background Art

[0002] In the process of natural gas extraction, a gas production tree is usually set up at the wellhead of the gas well to achieve gas extraction and flow control. The gas production tree is usually connected to the wellhead of the gas well by a main road. The main road is equipped with multiple branches connected to it. The branches are first connected to the main road, and then connected to the pipeline to transport natural gas. The main road and the branch road of the gas production tree usually have multiple valves. When the gas production tree is inspected and repaired, the valve of the main road can be closed. When a branch road is inspected and repaired, only the valve of this branch road can be closed. However, the current gas production wellheads can generally only adapt to a single size of casing to ensure the sealing effect. In addition, the existing gas production wellhead structure is large in size and needs to be connected separately as a section of the wellhead, which is not suitable for use inside the wellhead.

[0003] That is to say, in the prior art, the gas wellhead has the problem of poor compatibility with the casing. Summary of the invention

[0004] The main purpose of the present invention is to provide a gas production wellhead to solve the problem of poor compatibility between the gas production wellhead and the casing in the prior art.

[0005] In order to achieve the above-mentioned purpose, the present invention provides a gas production wellhead, comprising: an integral valve group, the integral valve group has connection ports facing four different directions, the connection ports are provided with control valves; a main passage, one end of the main passage is connected to a connection port, and the main passage is provided with a main control valve; an oil pipe head, the oil pipe head is connected to the other end of the main passage, and the oil pipe head has an oil pipe extending in a direction away from the main passage; a connecting head, the connecting head is connected to the oil pipe head, the connecting head has a central through hole, the central through hole is divided into a first hole section and a second hole section with different inner diameters, the hole wall of the central through hole has a step surface to connect the first hole section and the second hole section, and the pipe mouth of the oil pipe extends from the opening of the first hole section into the second hole section , the opening of the second hole section is used to extend into the casing so that the casing is connected to the oil pipe; an adapter ring, the adapter ring is replaceably arranged in the second hole section, the adapter ring abuts against the step surface, the adapter ring has an adapter hole, the aperture of the adapter hole is matched with the outer diameter of the oil pipe and the casing, so that the oil pipe and the casing are fixed in the adapter ring; an annular seal, the outer ring surface of the annular seal abuts against the hole wall surface of the second hole section, the annular seal abuts against the side of the adapter ring away from the step surface, and the inner ring surface of the annular seal abuts against the casing; a fixing ring, the outer ring surface of the fixing ring is threadedly connected to the hole wall surface of the second hole section, the fixing ring is arranged on the side of the annular seal away from the adapter ring, and the inner ring surface of the fixing ring abuts against the casing.

[0006] Furthermore, the gas production wellhead also has a plurality of sealing rings, and the hole wall surface of the second hole section also has a plurality of annular sealing grooves arranged at intervals, and the sealing rings are placed in the annular sealing grooves and match the size of the annular sealing grooves.

[0007] Furthermore, the adapter ring has an annular notch at one end close to the step surface to form an installation space between the outer ring surface of the adapter ring and the connector. The gas wellhead also has an outer ring, which is located in the installation space and abuts against the adapter ring and the connector.

[0008] Furthermore, the gas production wellhead also has a sealing sleeve, and the inner ring surface of the outer ring also has a closed groove. The sealing sleeve is arranged in the closed groove and matches the size of the closed groove.

[0009] Furthermore, at least one of the plurality of sealing rings abuts against the outer ring, so that the sealing ring seals the outer ring and the connector.

[0010] Furthermore, the gas production wellhead also has multiple sealing rings, and the hole wall of the adapter hole also has multiple annular sealing grooves arranged at intervals. The sealing rings are placed in the annular sealing grooves and match the sizes of the annular sealing grooves to seal the adapter ring and the casing.

[0011] Furthermore, the adapter ring has an annular flange extending toward the annular seal, and the annular seal has an annular groove at one end facing the adapter ring, and at least a portion of the annular flange extends into the annular groove and is clamped in the annular groove.

[0012] Furthermore, the fixing ring has an annular protrusion extending toward the annular seal, and the annular seal has an annular recess at one end facing the fixing ring, and at least a portion of the annular protrusion extends into the annular recess and is clamped in the annular recess.

[0013] Furthermore, the connector has a plurality of flow channels arranged at intervals, and the flow channels extend from the outer wall of the connector in a direction perpendicular to the central axis of the connector. The gas wellhead also includes a plurality of pressure test assemblies, and the pressure test assemblies are arranged in a one-to-one correspondence with the flow channels. The pressure test assemblies are connected to one end of the flow channel located on the outer wall of the connector to test the sealing inside the connector.

[0014] Further, at least one flow channel extends to the outer annular surface of the adapter ring; and / or at least one flow channel extends to the outer annular surface of the annular seal; and / or at least one flow channel passes through the adapter ring from the outer side wall of the connector.

[0015] According to the technical solution of the present invention, a gas production wellhead includes an integral valve group, a main passage, a tubing head, a connector, an adapter ring, an annular seal and a fixing ring. The integral valve group has connectors facing four different directions, and a control valve is provided at the connector. One end of the main passage is connected to a connector, and a main control valve is provided on the main passage. The tubing head is connected to the other end of the main passage, and the tubing head has an oil pipe extending away from the main passage. The connector is connected to the tubing head, and the connector has a central through hole, which is divided into a first hole section and a second hole section with different inner diameters. The hole wall of the central through hole has a step surface to connect the first hole section and the second hole section. The pipe mouth of the oil pipe is formed by the first hole section. The opening extends into the second hole section, and the opening of the second hole section is used to extend into the casing so that the casing is connected to the oil pipe; the adapter ring is replaceably arranged in the second hole section, the adapter ring abuts against the step surface, and the adapter ring has an adapter hole, and the aperture of the adapter hole is matched with the outer diameter of the oil pipe and the casing so that the oil pipe and the casing are fixed in the adapter ring; the outer ring surface of the annular seal abuts against the hole wall surface of the second hole section, the annular seal abuts against the side of the adapter ring away from the step surface, and the inner ring surface of the annular seal abuts against the casing; the outer ring surface of the fixing ring is threadedly connected with the hole wall surface of the second hole section, the fixing ring is arranged on the side of the annular seal away from the adapter ring, and the inner ring surface of the fixing ring abuts against the casing.

[0016] By setting four connection ports on the overall valve group, oil and gas can be transported in multiple ways, and a control valve is set at the connection port to control the oil and gas transportation of the branch. By connecting the main passage at a connection port and setting a main control valve on the main passage, it is possible to control whether the produced oil and gas are transported to other branches. At the same time, a tubing head and a connector are sequentially connected at the other end of the main passage, and an oil pipe is set inside the tubing head. The oil pipe extends into the connector and is connected to the casing to keep the oil and gas transportation pipeline unobstructed. By dividing the central through hole in the connector into a first hole section and a second hole section with different apertures, a setting space is provided for the adapter ring, and different outer diameters of the oil pipe and the casing can be adapted. The adapter ring is replaceably arranged in the second hole section, and the aperture sizes of multiple adapter holes can be set at the same time. That is to say, the adapter ring is provided with multiple models, each model has the same outer diameter and different inner diameters, so that the gas production wellhead of the present application can have good compatibility with casings of different sizes. The annular seal is abutted against the adapter ring and the annular seal is sleeved outside the sleeve to ensure the sealing between the connector and the sleeve. The fixing ring is screwed on one end of the annular seal to prevent the adapter ring and the annular seal from moving while ensuring the sealing effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0018] Figure 1 A schematic diagram of the external structure of a gas production wellhead according to the first embodiment of the present invention is shown;

[0019] Figure 2 Shows Figure 1 Schematic diagram of the internal structure of the connector.

[0020] The above drawings include the following reference numerals:

[0021] 10. Integral valve group; 11. Connecting port; 12. Control valve; 13. Elbow; 14. Branch valve; 20. Main passage; 21. Main control valve; 30. Tubing head; 31. Tubing; 32. Flat valve; 40. Connecting head; 41. First hole section; 42. Second hole section; 43. Step surface; 44. Sealing ring; 46. Flow channel; 47. Pressure test assembly; 50. Adapter ring; 51. Sealing ring; 53. Annular flange; 60. Annular seal; 61. Annular groove; 62. Annular recess; 70. Retaining ring; 71. Annular protrusion; 80. Casing; 90. Outer ring; 91. Sealing sleeve. DETAILED DESCRIPTION

[0022] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0023] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meanings as commonly understood by ordinary technicians in the technical field to which this application belongs.

[0024] In the present invention, unless otherwise specified, the directional words used, such as "up, down, top, bottom", usually refer to the directions shown in the drawings, or to the components themselves in the vertical, perpendicular or gravity directions; similarly, for ease of understanding and description, "inside and outside" refer to the inside and outside relative to the outline of each component itself, but the above-mentioned directional words are not used to limit the present invention.

[0025] In order to solve the problem of poor compatibility between a gas production wellhead and a casing in the prior art, the present invention provides a gas production wellhead.

[0026] like Figure 1 and Figure 2As shown, the gas production wellhead includes an integral valve group 10, a main passage 20, a tubing head 30, a connector 40, an adapter ring 50, an annular seal 60 and a fixing ring 70. The integral valve group 10 has a connection port 11 facing four different directions, and the connection port 11 is provided with a control valve 12; one end of the main passage 20 is connected to a connection port 11, and the main passage 20 is provided with a main control valve 21; the tubing head 30 is connected to the other end of the main passage 20, and the tubing head 30 has an oil pipe 31 extending in a direction away from the main passage 20; the connector 40 is connected to the tubing head 30, and the connector 40 has a central through hole, which is divided into a first hole section 41 and a second hole section 42 with different inner diameters, and a step surface 43 is provided on the hole wall of the central through hole to connect the first hole section 41 and the second hole section 42, and the pipe mouth of the oil pipe 31 extends from the opening of the first hole section 41 The adapter ring 50 is replaceably arranged in the second hole section 42, and the adapter ring 50 abuts against the step surface 43. The adapter ring 50 has an adapter hole, and the aperture of the adapter hole is matched with the outer diameter of the oil pipe 31 and the casing 80, so that the oil pipe 31 and the casing 80 are fixed in the adapter ring 50; the outer ring surface of the annular seal 60 abuts against the hole wall surface of the second hole section 42, the annular seal 60 abuts against the side of the adapter ring 50 away from the step surface 43, and the inner ring surface of the annular seal 60 abuts against the casing 80; the outer ring surface of the fixing ring 70 is threadedly connected with the hole wall surface of the second hole section 42, the fixing ring 70 is arranged on the side of the annular seal 60 away from the adapter ring 50, and the inner ring surface of the fixing ring 70 abuts against the casing 80.

[0027] By setting four connection ports 11 on the integral valve group 10, oil and gas can be transported in multiple ways, and a control valve 12 is set at the connection port 11 to control the oil and gas transportation of the branch. By connecting the main passage 20 at a connection port 11 and setting a main control valve 21 on the main passage 20, it is possible to control whether the produced oil and gas are transported to other branches. At the same time, the other end of the main passage 20 is connected in sequence with a tubing head 30 and a connector 40, and an oil pipe 31 is set inside the tubing head 30. The oil pipe 31 extends into the connector 40 and is connected to the casing 80 to keep the oil and gas transportation pipeline unobstructed. By dividing the central through hole in the connector 40 into a first hole section 41 and a second hole section 42 with different apertures, a setting space is provided for the adapter ring 50, and different outer diameters of the oil pipe 31 and the casing 80 can be adapted. The adapter ring 50 is replaceably arranged in the second hole section 42, and a variety of aperture sizes of the adapter hole can be set. That is to say, the adapter ring 50 has multiple models, each model has the same outer diameter and different inner diameters, so that the gas wellhead of the present application can have good compatibility with casings 80 of different sizes. By abutting the annular seal 60 on the adapter ring 50 and sleeved on the outside of the casing 80, the sealing between the connector 40 and the casing 80 can be ensured. The fixing ring 70 is screwed on one end of the annular seal 60 to prevent the adapter ring 50 and the annular seal 60 from moving, while ensuring the sealing effect.

[0028] It should be noted that in the present application, the outer diameter of the oil pipe 31 matches the aperture of the first hole section 41, the outer diameters of the adapter ring 50, the annular seal 60, and the fixing ring 70 match the aperture of the second hole section 42, the inner diameters of the adapter ring 50, the annular seal 60, and the fixing ring 70 match the outer diameter of the casing 80, the adapter ring 50 abuts against the step surface 43, the annular seal 60 abuts against the adapter ring 50, and the fixing ring 70 abuts against the annular seal 60, which can avoid shaking due to instability of the internal structure and is conducive to ensuring sealing.

[0029] Optionally, the annular seal 60 includes an H-type metal seal ring or an O-type seal ring.

[0030] like Figure 1 As shown, the openings of the two connection ports 11 adjacent to the main passage 20 are oriented at an angle greater than 90° with the main passage 20, and the two connection ports 11 adjacent to the main passage 20 are respectively connected to an elbow 13, and the center of the elbow 13 is close to the main passage 20. A branch valve 14 is provided at the other end of the elbow 13 to control the oil and gas flow of the branch. The elbow 13 can ensure the sealing performance while reducing the direct impact of the oil and gas on the pipe wall when flowing from the main passage 20 to the other branches, thereby improving the erosion resistance.

[0031] It should be noted that among the control valves 12 on the integral valve group 10, the control valve 12 at the connection port 11 connected to the main passage 20 can be a hydraulic valve, and the rest are manual valves, the branch valve 14 can be a hydraulic valve or a manual valve, and the main control valve 21 provided on the main passage 20 is a manual valve, that is, there is at least one manual valve and one hydraulic valve on the pipelines connected up and down or left and right, so that when the hydraulic valve fails, the oil and gas flow in the passage can be closed by the manual valve. Here, the hydraulic valve can be selected as other automatically controlled valves.

[0032] like Figure 1 As shown, at least two flat valves 32 are respectively arranged on both sides of the tubing head 30, and the flat valves 32 are manual valves to control the passages connected on both sides of the tubing head 30, and at the same time improve the safety factor. Generally, the site requires double cutoff, so there will be two flat valves 32. The two sides of the tubing head 30 are symmetrically designed, so that the relevant operations on site are all carried out from the left or right, which is convenient for on-site operation.

[0033] It should be noted that both ends of the main passage 20 are connected to the connection port 11 and the tubing head 30 through flanges.

[0034] like Figure 2 As shown, the gas production wellhead also has a plurality of sealing rings 44, and the hole wall surface of the second hole section 42 also has a plurality of annular sealing grooves arranged at intervals, and the sealing rings 44 are placed in the annular sealing grooves and match the size of the annular sealing grooves. The sealing rings 44 can fit the connector 40 and the adapter ring 50 to ensure the sealing of the two.

[0035] Optionally, the sealing ring 44 includes at least one of an H-type metal sealing ring and an O-type sealing ring.

[0036] like Figure 2 As shown, the end of the adapter ring 50 close to the step surface 43 has an annular notch, so that an installation space is formed between the outer ring surface of the adapter ring 50 and the connector 40, and the gas production wellhead also has an outer ring 90, which is located in the installation space, and the outer ring 90 abuts against the adapter ring 50 and the connector 40. By sleeve-arranging the outer ring 90 on the end of the adapter ring 50 close to the step surface 43, it is beneficial to improve the sealing performance, and it is convenient to adjust the slight installation error, so as to avoid the difficulty of inserting the adapter ring 50 as a whole when the interference fit is generated due to processing, and play a guiding positioning effect.

[0037] Optionally, the inner ring surface of the outer ring 90 is parallel to the central axis of the second hole segment 40 , and the position where the adapter ring 50 and the inner ring surface of the outer ring 90 are matched is also parallel to the central axis of the second hole segment 40 .

[0038] In a specific embodiment not shown in the figure, the inner ring surface of the outer ring 90 is set at an angle with the central axis of the second hole segment 40, so that the inner radial direction of the outer ring 90 gradually decreases in the direction approaching the step surface 43, and at least a portion of the adapter ring 50 is kept in contact with the step surface 43. At the same time, the adapter ring 50 is set to fit the inner ring surface of the outer ring 90 and is also inclined at a certain angle to facilitate the installation and docking of the two.

[0039] like Figure 2 As shown, the gas production wellhead also has a sealing sleeve 91, and the inner ring surface of the outer ring 90 also has a closed groove, and the sealing sleeve 91 is arranged in the closed groove and matches the size of the closed groove. In other words, the sealing sleeve 91 fits the matching ring 50 and the outer ring 90 to improve the sealing between the two.

[0040] It should be noted that the size of the sealing sleeve 91 is relatively small to ensure the structural stability of the outer ring 90. Preferably, the length of the sealing sleeve 91 is less than half of the outer ring 90.

[0041] like Figure 2 As shown, at least one of the plurality of sealing rings 44 abuts against the outer ring 90, so that the sealing ring 44 seals the outer ring 90 and the connector 40. The sealing ring 44 can fit the connector 40 and the outer ring 90 to ensure the sealing of the two.

[0042] like Figure 2 As shown, the gas production wellhead also has a plurality of sealing rings 51, and the hole wall surface of the adapter hole also has a plurality of annular sealing grooves arranged at intervals. The sealing ring 51 is placed in the annular sealing groove and matches the size of the annular sealing groove. That is, the sealing ring 51 fits the adapter ring 50 and the casing 80 to seal the two.

[0043] like Figure 2 As shown, the adapter ring 50 has an annular flange 53 extending toward the annular seal 60, and the annular seal 60 has an annular groove 61 at one end facing the adapter ring 50, and at least a portion of the annular flange 53 extends into the annular groove 61 and is clamped in the annular groove 61. The annular flange 53 extends into the annular groove 61 and is clamped, which prevents shaking between the adapter ring 50 and the annular seal 60, and helps to ensure sealing.

[0044] It should be noted that, except for the portion where the annular flange 53 and the annular groove 61 are pressed against each other, the remaining positions between the adapter ring 50 and the annular seal 60 can be spaced apart or can be fitted together without affecting the sealing between the adapter ring 50 and the annular seal 60 .

[0045] like Figure 2As shown, the fixing ring 70 has an annular protrusion 71 extending toward the annular seal 60, and the annular seal 60 has an annular recess 62 at one end facing the fixing ring 70, and at least a portion of the annular protrusion 71 extends into the annular recess 62 and is clamped in the annular recess 62. The annular protrusion 71 extends into the annular recess 62 and is clamped, so that shaking between the fixing ring 70 and the annular seal 60 is avoided, and the sealing is ensured at the same time.

[0046] It should be noted that, except for the portion where the annular protrusion 71 and the annular recess 62 are pressed against each other, the remaining positions between the fixing ring 70 and the annular seal 60 can be spaced apart or can be closely fitted, which does not affect the sealing between the fixing ring 70 and the annular seal 60 .

[0047] like Figure 2 As shown, the connector 40 has a plurality of flow channels 46 arranged at intervals, and the flow channels 46 extend from the outer wall of the connector 40 in a direction perpendicular to the central axis of the connector 40. The gas production wellhead also includes a plurality of pressure test assemblies 47, and the pressure test assemblies 47 are arranged one by one corresponding to the flow channels 46. The pressure test assemblies 47 are connected to one end of the flow channel 46 located on the outer wall of the connector 40 to test the sealing inside the connector 40. It should be noted that the pressure test assembly 47 has good sealing performance, and has little effect on the sealing inside the connector 40, which can be ignored.

[0048] Preferably, at least one flow channel 46 extends to the outer annular surface of the adapter ring 50 so as to test the sealing between the adapter ring 50 and the connector 40 .

[0049] Preferably, at least one flow channel 46 extends to the outer annular surface of the annular seal 60 so as to test the sealing performance between the annular seal 60 and the connector 40 .

[0050] Preferably, at least one flow channel 46 passes through the adapter ring 50 from the outer wall of the connector 40 , that is, the flow channel 46 passes through the outer wall of the connector 40 to the sleeve 80 , so as to test the sealing between the sleeve 80 , the annular seal 60 and the connector 40 .

[0051] It should be noted that both sides of the end point of the flow channel 46 extending inward are provided with structural parts that play a sealing role, and the pressure test assembly 47 can test the sealing effect of the structural parts that play a sealing role adjacent to the flow channel 46. For example, the two sides adjacent to the flow channel 46 extending to the outer annular surface of the adapter ring 50 can be provided with a sealing ring 44, or a sealing ring 44 and an annular seal 60 can be provided on the two adjacent sides; the two sides adjacent to the flow channel 46 extending to the outer annular surface of the annular seal 60 can be an annular seal 60, or an annular seal 60 and a fixing ring 70; the two sides adjacent to the flow channel 46 passing through the adapter ring 50 can be provided with a sealing ring 44.

[0052] When the gas production wellhead of the present application is in use, the adapter ring 50 matching the size of the casing needs to be installed in place to ensure the sealing effect, and then the casing is connected and a pressure test is performed. Only after the pressure test is correct can the gas production operation be carried out.

[0053] Embodiment 1

[0054] like Figure 1 and Figure 2 As shown, two of the connectors 40 are each provided with two flow channels 46 , and the heights of the four flow channels 46 are different to test the sealing and pressure-maintaining effects at different positions.

[0055] Specifically, a flow channel 46 extends to an end of the outer ring surface of the adapter ring 50 close to the outer ring 90 , so as to test the sealing effect of the sealing ring 44 on the outer ring 90 , the adapter ring 50 and the connector 40 .

[0056] Specifically, a flow channel 46 extends to an end of the outer annular surface of the adapter ring 50 close to the annular seal 60 , so as to test the sealing effect of the sealing ring 44 and the annular seal 60 on the adapter ring 50 and the connector 40 .

[0057] Specifically, a flow channel 46 passes through the adapter ring 50 from the outer wall of the connector 40 to test the sealing effect of the sealing ring 44 and the sealing ring 51 on the sleeve 80 , the adapter ring 50 and the connector 40 .

[0058] Specifically, a flow channel 46 extends to one end of the annular seal 60 close to the fixing ring 70 , so as to test the sealing performance between the annular seal 60 , the fixing ring 70 and the connector 40 .

[0059] From the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0060] 1. By setting four connection ports 11 on the integral valve group 10, oil and gas can be transported in multiple ways. At the same time, a control valve 12 is set at the connection port 11 to control the oil and gas transportation of the branch.

[0061] 2. By connecting the main passage 20 at a connection port 11 and setting a main control valve 21 on the main passage 20, it is possible to control whether the produced oil and gas are transported to other branches. At the same time, the other end of the main passage 20 is connected in sequence with a tubing head 30 and a connector 40. An oil pipe 31 is arranged inside the tubing head 30. The oil pipe 31 extends into the connector 40 and is connected to the casing 80 to keep the oil and gas transmission pipeline unobstructed.

[0062] 3. By dividing the central through hole in the connector 40 into a first hole section 41 and a second hole section 42 with different hole diameters, a setting space is provided for the adapter ring 50 , and different outer diameters of the oil pipe 31 and the casing 80 can be adapted.

[0063] 4. The adapter ring 50 is replaceably arranged in the second hole section 42, and a variety of aperture sizes of the adapter hole can be set. That is, the adapter ring 50 has multiple models, each model has the same outer diameter and different inner diameters, so that the gas production wellhead of the present application can have good compatibility with casings 80 of different sizes. By abutting the annular seal 60 on the adapter ring 50 and sleeved on the outside of the casing 80, the sealing between the connector 40 and the casing 80 can be ensured.

[0064] 5. Tighten the fixing ring 70 onto one end of the annular seal 60 to prevent the adapter ring 50 and the annular seal 60 from moving while ensuring the sealing effect.

[0065] Obviously, the above-described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0066] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0067] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein.

[0068] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A gas production wellhead, characterized in that: include: An integral valve assembly (10), the integral valve assembly (10) having connection ports (11) facing four different directions, the connection ports (11) being provided with control valves (12); a main passage (20), one end of the main passage (20) being connected to one of the connection ports (11), and a main control valve (21) being provided on the main passage (20); A tubing head (30), the tubing head (30) being connected to the other end of the main passage (20), the tubing head (30) having an oil pipe (31) extending in a direction away from the main passage (20); A connector (40), the connector (40) being connected to the oil pipe head (30), the connector (40) having a central through hole, the central through hole being divided into a first hole section (41) and a second hole section (42) having different inner diameters, the hole wall of the central through hole having a step surface (43) for connecting the first hole section (41) and the second hole section (42), the pipe mouth of the oil pipe (31) extending from the opening of the first hole section (41) into the second hole section (42), the opening of the second hole section (42) being used for extending a casing (80) so that the casing (80) is connected to the oil pipe (31); an adapter ring (50), the adapter ring (50) being replaceably arranged in the second hole section (42), the adapter ring (50) being in contact with the step surface (43), the adapter ring (50) having an adapter hole, the hole diameter of the adapter hole being matched with the outer diameter of the oil pipe (31) and the sleeve (80), so that the oil pipe (31) and the sleeve (80) are fixed in the adapter ring (50); an annular seal (60), wherein the outer annular surface of the annular seal (60) abuts against the hole wall surface of the second hole section (42), the annular seal (60) abuts against a side of the adapter ring (50) away from the step surface (43), and the inner annular surface of the annular seal (60) abuts against the sleeve (80); A fixing ring (70), the outer ring surface of which is threadedly connected to the hole wall surface of the second hole section (42), the fixing ring (70) is arranged on a side of the annular seal (60) away from the adapter ring (50), and the inner ring surface of the fixing ring (70) is in contact with the sleeve (80).

2. The gas production wellhead according to claim 1, characterized in that: The gas production wellhead also has a plurality of sealing rings (44), and the hole wall surface of the second hole section (42) also has a plurality of annular sealing grooves arranged at intervals, and the sealing rings (44) are placed in the annular sealing grooves and match the size of the annular sealing grooves.

3. The gas production wellhead according to claim 2, characterized in that: The adapter ring (50) has an annular notch at one end close to the step surface (43) so that an installation space is formed between the outer ring surface of the adapter ring (50) and the connector (40). The gas production wellhead also has an outer ring (90), which is located in the installation space and abuts against the adapter ring (50) and the connector (40).

4. The gas production wellhead according to claim 3, characterized in that: The gas production wellhead also has a sealing sleeve (91), and the inner ring surface of the outer ring (90) also has a closed groove. The sealing sleeve (91) is arranged in the closed groove and matches the size of the closed groove.

5. The gas production wellhead according to claim 3, characterized in that: At least one of the plurality of sealing rings (44) abuts against the outer ring (90), so that the sealing ring (44) seals the outer ring (90) and the connector (40).

6. The gas production wellhead according to claim 1, characterized in that: The gas production wellhead also has a plurality of sealing rings (51), and the wall surface of the adapter hole also has a plurality of annular sealing grooves arranged at intervals. The sealing ring (51) is placed in the annular sealing groove and matches the size of the annular sealing groove to seal the adapter ring (50) and the casing (80).

7. The gas production wellhead according to claim 1, characterized in that: The adapter ring (50) has an annular flange (53) extending toward the annular seal (60), and the annular seal (60) has an annular groove (61) at one end facing the adapter ring (50), and at least a portion of the annular flange (53) extends into the annular groove (61) and is clamped in the annular groove (61).

8. The gas production wellhead according to any one of claims 1 to 7, characterized in that: The fixing ring (70) has an annular protrusion (71) extending toward the annular seal (60), and the annular seal (60) has an annular recess (62) at one end facing the fixing ring (70), and at least a portion of the annular protrusion (71) extends into the annular recess (62) and is clamped in the annular recess (62).

9. The gas production wellhead according to any one of claims 1 to 7, characterized in that: The connector (40) has a plurality of flow channels (46) arranged at intervals, and the flow channels (46) extend from the outer wall of the connector (40) in a direction perpendicular to the central axis of the connector (40). The gas production wellhead also includes a plurality of pressure test assemblies (47), and the pressure test assemblies (47) are arranged in a one-to-one correspondence with the flow channels (46). The pressure test assemblies (47) are connected to one end of the flow channel (46) located on the outer wall of the connector (40) to test the sealing inside the connector (40).

10. The gas production wellhead according to claim 9, characterized in that: At least one of the flow channels (46) extends to the outer annular surface of the adapter ring (50); and / or At least one of the flow channels (46) extends to the outer annular surface of the annular seal (60); and / or At least one of the flow channels (46) passes through the adapter ring (50) from the outer wall of the connector (40).

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