A petroleum casing head having a sealing structure

Abstract

The application belongs to the technical field of oil casing heads and provides an oil casing head with a sealing structure. The oil casing head comprises a main body, an upper flange connected to the upper side of the main body, a technical casing connected to the lower side of the main body, an annular sliding groove arranged on the upper side of the main body, a sliding ring slidingly connected in the annular sliding groove, a mounting ring fixedly connected to the upper side of the sliding ring, the mounting ring slidingly connected to the main body, a sealing gasket fixedly connected to the upper side of the mounting ring, the sealing gasket in extrusion fit with the upper flange, and the main body provided with first communication holes uniformly distributed in the circumference. The application changes the extrusion degree of the sealing gasket according to the pressure of the injected material in the main body, so that the sealing gasket is extruded with small force when the pressure of the material in the main body is small and is extruded with large force when the pressure of the material in the main body is large, thereby prolonging the service life of the sealing gasket while ensuring the sealing property, reducing the non-production time in the process of oil exploitation, and improving the production efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of oil casing heads, in particular to an oil casing head with a sealing structure. BACKGROUND

[0002] The casing head is used to connect the casing in oil exploitation, to ensure the sealing and stable connection from the surface casing to the oil layer casing, to support the weight of the casing except the surface casing, including the technical casing and the production casing, and to provide a solid foundation for the whole wellhead device, and a side port is usually arranged on the casing head, which can be used to inject materials such as mud, cement, well killing fluid or fire extinguishing agent, and to inject pressure balancing fluid during acidizing fracturing in special operations, and the upper side of the casing head is usually connected with the wellhead device (including the blowout preventer group) through a flange or a clamp, and when the casing head is connected with the flange, a sealing gasket is usually arranged to realize sealing, so as to avoid leakage when the materials are injected into the casing head, and the existing sealing methods are mainly metal winding gaskets and non-metal gaskets (such as rubber and graphite), which are located between the two flange surfaces, and when the flange is tightly fixed by bolts, the gasket is deformed by extrusion, and fills the small concave-convex between the flange surfaces, so as to form a seal, and in this way, the pressure on the sealing gasket is set according to the maximum pressure of the materials injected into the casing, so as to ensure the sealing effect, and therefore the sealing gasket is always under high pressure after installation, which shortens the service life of the sealing gasket, and the sealing gasket needs to be replaced when its service life is close to the end, so as to avoid the damage of the sealing gasket to the production during the production process, and the short service life of the sealing gasket increases the non-production time during the oil exploitation process, and affects the production efficiency. SUMMARY

[0003] In order to overcome the shortcomings mentioned in the background, the present application provides an oil casing head with a sealing structure.

[0004] The technical scheme of the present application is as follows: an oil casing head with a sealing structure, comprising a main body, the upper side of the main body is connected with an upper flange, the lower side of the main body is connected with a technical casing, the upper side of the main body is provided with an annular sliding groove, a sliding ring is slidably connected in the annular sliding groove, the upper side of the sliding ring is fixedly connected with a mounting ring, the mounting ring is slidably connected with the main body, the upper side of the mounting ring is fixedly connected with a sealing gasket, the sealing gasket is extrudedly matched with the upper flange, the main body is provided with first communication holes which are uniformly distributed in the circumferential direction, and the first communication holes collectively communicate the annular sliding groove with the inner side of the main body.

[0005] As a preferred technical scheme of the present application, the upper side of the sealing gasket is higher than the upper side of the main body, so that the sealing gasket is extruded when the main body and the upper flange are connected.

[0006] As a preferred technical scheme of the present application, the upper side of the longitudinal section of the mounting ring is wavy, and the upper and lower sides of the longitudinal section of the sealing gasket are wavy, so as to increase the contact area between the mounting ring and the sealing gasket.

[0007] As a preferred technical scheme of the present application, the main body is embedded with two sealing rings, and the two sealing rings are in sliding extrusion fit with the sliding ring.

[0008] As a preferred technical scheme of the present application, the volume of the part of the sealing ring embedded in the main body is greater than the volume of the part of the sealing ring located in the annular sliding groove, so as to prevent the displacement of the sealing ring.

[0009] As a preferred technical scheme of the present application, the longitudinal section of the sliding ring is isosceles trapezoidal, with the upper base shorter than the lower base, so as to change the force when the sliding ring is extruded by the two sealing rings.

[0010] As a preferred technical scheme of the present application, the hollow ring is further provided, which is fixed to the upper side of the main body and in extrusion fit with the upper flange, the main body is provided with second communication holes which are uniformly distributed in the circumferential direction and in communication with the hollow ring, and the upper side of the main body is provided with a partition table which is provided with an annular groove, and the second communication holes are in communication with the annular groove of the partition table.

[0011] As a preferred technical scheme of the present application, the second communication holes are slidingly connected with sliding columns on the side close to the axis of the main body, and the sliding columns which are uniformly distributed in the circumferential direction are collectively fixed with a pressure receiving ring, the pressure receiving ring is in sliding connection with the main body, and the second communication holes and the hollow ring are filled with liquid.

[0012] As a preferred technical scheme of the present application, the upper side of the pressure receiving ring is lower than the upper side of the main body, and the upper side of the pressure receiving ring is flush with the upper side of the partition table, so as to extrude the pressure receiving ring by the leaked material due to the damage of the sealing gasket.

[0013] As a preferred technical scheme of the present application, the contact area of the pressure receiving ring with the leaked material is greater than the contact area of the hollow ring with the leaked material.

[0014] Beneficial effects: The present application changes the extrusion degree of the sealing gasket according to the pressure of the injected material in the main body, so that the sealing gasket receives small extrusion force when the pressure of the material in the main body is small, and receives large extrusion force when the pressure of the material in the main body is large, thereby prolonging the service life of the sealing gasket while ensuring the sealing performance, and further reducing the non-production time in the process of oil exploitation and improving the production efficiency.

[0015] The upper and lower sides of the longitudinal section of the sealing gasket are arranged in a wave shape, thereby increasing the contact area between the sealing gasket and the mounting ring and the upper flange, improving the sealing performance of the sealing gasket, and after the sealing gasket is damaged and broken, the upper side of the mounting ring is in a wave shape, thereby forming a groove accommodating the sealing gasket, preventing the broken sealing gasket from being separated to form a larger fracture under the pressure of the material in the main body, and avoiding the material from leaking in a gushing manner due to the broken sealing gasket.

[0016] The longitudinal section of the sliding ring is arranged in an isosceles trapezoidal shape, so that when the sliding ring moves upward under a large pressure of the material in the main body, the extrusion force on the two sealing rings is increased, thereby improving the sealing performance between the sliding ring and the two sealing rings and preventing material leakage.

[0017] After the material leaks, the pressure of the material acts on the pressure receiving ring, so that the pressure receiving ring moves downward and drives the hollow ring to expand, thereby increasing the pressure between the hollow ring and the upper flange, forming a temporary seal between the main body and the upper flange, providing time for subsequent maintenance personnel to repair, and preventing the material from leaking in large quantities during this period to pollute the production equipment and cause waste. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a schematic diagram of the three-dimensional structure of the present application;

[0019] Figure 2 is a schematic diagram of the three-dimensional structure of the main body and the upper flange of the present application;

[0020] Figure 3 is a schematic diagram of the three-dimensional structure of the sliding ring and the sealing gasket of the present application;

[0021] Figure 4 is a schematic diagram of the three-dimensional structure of the hollow ring and the pressure receiving ring of the present application.

[0022] Wherein: 1-main body, 101-annular sliding groove, 102-first communication hole, 103-second communication hole, 104-separation table, 2-upper flange, 3-technical sleeve, 4-sliding ring, 5-mounting ring, 6-sealing gasket, 7-sealing ring, 8-hollow ring, 9-sliding column, 10-pressure receiving ring. DETAILED DESCRIPTION

[0023] For those skilled in the art, the specific meanings of the above terms in this application can be understood in specific circumstances. The electronic device provided by the embodiments of the present application will be described in detail below in combination with the drawings and specific examples and their application scenarios.

[0024] The existing sleeve head forms a seal by extruding a sealing gasket, and the sealing gasket is in a high-pressure state for a long time, resulting in a short service life of the sealing gasket. The short service life of the sealing gasket will increase the non-production time during oil extraction and affect the production efficiency.

[0025] Example 1: An oil casing head with a sealing structure, such as Figures 1-4 As shown, the device includes a main body 1, with its upper side connected to an upper flange 2 and its lower side connected to a technical sleeve 3. An annular groove 101 is provided on the upper side of the main body 1, allowing a sliding ring 4 and a mounting ring 5 to move vertically. The sliding ring 4 is slidably connected within the annular groove 101, and a mounting ring 5 is fixedly connected to its upper side. The mounting ring 5 cooperates with a sealing gasket 6 to form a seal. The mounting ring 5 is slidably connected to the main body 1 and is located within the annular groove 101. A sealing gasket 6 is fixedly connected to the upper side of the mounting ring 5, with its upper side higher than the upper side of the main body 1. This allows the sealing gasket 6 to be compressed when the main body 1 and the upper flange 2 are connected, resulting in a compression fit between the sealing gasket 6 and the upper flange 2. When the main body 1 and the upper flange 2 are connected, the mounting ring 5 and the upper flange 2 compress the sealing gasket 6 to form a seal. The upper side of the longitudinal section of the mounting ring 5 is wavy, and the upper and lower sides of the longitudinal section of the sealing gasket 6 are also wavy, which is used to increase the contact area between the mounting ring 5 and the sealing gasket 6, thereby improving the sealing performance. The main body 1 is provided with several (six in this example) first connecting holes 102 evenly distributed in the circumference. The six first connecting holes 102 together connect the annular groove 101 with the inner side of the main body 1, so that the material flowing inside the main body 1 can enter the annular groove 101, and then use the pressure of the material to provide pressure to the sliding ring 4, so that the sliding ring 4 drives the mounting ring 5 to further compress the sealing gasket 6, thereby improving the sealing performance.

[0026] like Figure 3 and Figure 4 As shown, two sealing rings 7 are embedded in the main body 1. The sealing rings 7 are used to provide a seal between the sliding ring 4 and the main body 1. Both sealing rings 7 are in sliding compression fit with the sliding ring 4. The sealing rings 7 and the sliding ring 4 are initially in a compressed state. When the sliding ring 4 moves upward, the sliding ring 4 further compresses the two sealing rings 7, thereby improving the sealing performance. The volume of the part of the sealing ring 7 embedded in the main body 1 is larger than the volume of the part of the sealing ring 7 located in the annular groove 101, which is used to prevent the sealing ring 7 from shifting, thereby providing a good sealing effect. The longitudinal section of the sliding ring 4 is an isosceles trapezoid with a shorter upper base and a longer lower base, which is used to change the force when the sliding ring 4 compresses the two sealing rings 7. When the sliding ring 4 moves upward, the compressive force of the sliding ring 4 on the sealing ring 7 increases, and the sealing performance is improved.

[0027] When the device is used, first, the main body 1 is connected with the upper flange 2 and the technical sleeve 3, so that the material for assisting oil exploitation can flow through the main body 1, the upper flange 2 and the technical sleeve 3, when the main body 1 is connected with the upper flange 2, the mounting ring 5 is extruded together with the upper flange 2 to seal the gasket 6, so that a seal is formed between the three, preventing material leakage, when the material is injected into the main body 1, the material flows into the first communication hole 102, and then the sliding ring 4 moves upward under the pressure of the material, the sliding ring 4 pushes the mounting ring 5 to move upward, the mounting ring 5 further extrudes the gasket 6, so as to improve the sealing between the mounting ring 5, the gasket 6 and the upper flange 2, preventing material leakage, when the pressure of the material in the main body 1 is small, the sliding ring 4 is less pressed by the material, and the gasket 6 is less extruded by the mounting ring 5, but the sealing can still be achieved, so as to realize the function of changing the sealing effect of the gasket 6 according to the pressure of the material in the main body 1, so that the gasket 6 is less extruded when the pressure of the material in the main body 1 is small, and is more extruded when the pressure of the material in the main body 1 is large, so as to prolong the service life of the gasket 6 while ensuring the sealing, thereby reducing the non-production time in the process of oil exploitation and improving the production efficiency, when the sliding ring 4 moves upward, because the cross section of the sliding ring 4 is trapezoidal, the sliding ring 4 will further extrude the two sealing rings 7 when it moves upward, so as to improve the sealing between the sliding ring 4 and the two sealing rings 7, preventing material leakage.

[0028] The gasket has a risk of damage during use, and when the gasket is damaged, it will affect production and cause material leakage, polluting production equipment and affecting maintenance.

[0029] Example 2: based on example 1, as shown in Figures 2-4 the hollow ring 8 is also provided, the hollow ring 8 is made of elastic material, the hollow ring 8 is fixed to the upper side of the main body 1, the hollow ring 8 is extruded with the upper flange 2, the extrusion force between the hollow ring 8 and the upper flange 2 is small at the beginning, so as to prevent the hollow ring 8 from failing, the main body 1 is provided with a plurality of (six are taken as an example) second communication holes 103 which are uniformly distributed in the circumference, the second communication holes 103 are U-shaped, the second communication holes 103 are communicated with the hollow ring 8, the upper side of the main body 1 is provided with a partition table 104, the partition table 104 is used to make the leaked material reach the upper side thereof, the partition table 104 is provided with an annular groove, the second communication hole 103 is communicated with the annular groove of the partition table 104.

[0030] as shown in Figures 2-4As shown, the second communication hole 103 is slidingly connected with a sliding column 9 on one side close to the axis of the main body 1, six sliding columns 9 are fixedly connected with a pressure ring 10, the pressure ring 10 is slidingly connected with the main body 1, and the pressure ring 10 is located in the annular groove of the partition table 104; when the material reaches the upper side of the partition table 104 and the pressure ring 10, the material extrudes the pressure ring 10 to move downward, the upper side of the pressure ring 10 is lower than the upper side of the main body 1, and the upper side of the pressure ring 10 is flush with the upper side of the partition table 104, so as to extrude the pressure ring 10 by the material leaking due to damage of the sealing gasket 6, the contact area of the pressure ring 10 with the leaking material is greater than the contact area of the hollow ring 8 with the leaking material, so that the pressure ring 10 can press the liquid in the second communication hole 103 into the hollow ring 8 through the sliding column 9, and the second communication hole 103 and the hollow ring 8 are filled with liquid.

[0031] When the sealing gasket 6 or the sealing ring 7 is damaged due to not being replaced in time or other reasons, the material leaks from the inner side of the main body 1 to the upper side of the partition table 104 due to poor sealing, and after the upper side of the partition table 104 and the pressure ring 10 is full of material, the pressure of the material acts on the pressure ring 10, the material extrudes the pressure ring 10 to move downward, the pressure ring 10 pushes the six sliding columns 9 to move downward, the sliding column 9 extrudes the liquid in the adjacent second communication hole 103 into the hollow ring 8, the liquid in the hollow ring 8 increases, the pressure increases, the hollow ring 8 expands, the extrusion force between the hollow ring 8 and the upper flange 2 increases, so as to realize temporary sealing, provide time for subsequent maintenance personnel to repair, prevent the material from leaking in large quantities to pollute the production equipment and cause waste during this period, and then the maintenance personnel stops injecting the material into the main body 1, and the upper flange 2 is detached from the main body 1, at this time, the upper side of the partition table 104 and the pressure ring 10 is in communication with the air, the pressure of the leaking material on the pressure ring 10 decreases, the hollow ring 8 restores under the action of its own elasticity, and the liquid in the hollow ring 8 is pressed into the six second communication holes 103, and then the six sliding columns 9 drive the pressure ring 10 to reset, and then the damaged sealing gasket 6 or sealing ring 7 is replaced, and the part of the upper side of the main body 1 contaminated by the leaked material is cleaned, and then the upper flange 2 is reinstalled to continue production.

[0032] The above has introduced the present application in detail, and the principle and implementation mode of the present application have been described by applying specific examples; the above examples are only used to help understand the method of the present application and its core idea; meanwhile, for those skilled in the art, according to the idea of the present application, the specific implementation mode and application range can be changed, and the above description should not be understood as limiting the present application.

Claims

1. A petroleum casing head with a sealing structure, comprising a main body (1), the upper side of which is connected with an upper flange (2), and the lower side of which is connected with a technical casing (3), characterized in that, The upper side of the main body (1) is provided with an annular sliding groove (101), the sliding ring (4) is slidably connected in the annular sliding groove (101), the upper side of the sliding ring (4) is fixedly connected with the mounting ring (5), the mounting ring (5) is slidably connected with the main body (1), the upper side of the mounting ring (5) is fixedly connected with the sealing gasket (6), the sealing gasket (6) is extrudedly matched with the upper flange (2), the main body (1) is provided with circumferentially uniformly distributed first communication holes (102), and the circumferentially uniformly distributed first communication holes (102) are in communication with the inner side of the main body (1) together. The upper side of the sealing gasket (6) is higher than the upper side of the main body (1), so that the sealing gasket (6) is extruded when the main body (1) is connected with the upper flange (2). The upper side of the longitudinal section of the mounting ring (5) is wavy, and the upper and lower sides of the longitudinal section of the sealing gasket (6) are wavy, so as to increase the contact area between the mounting ring (5) and the sealing gasket (6). The main body (1) is embeddedly provided with two sealing rings (7). The longitudinal section of the sliding ring (4) is isosceles trapezoidal, the upper base is short, the lower base is long, and the force when the sliding ring (4) is extruded by the two sealing rings (7) is changed. Further comprising a hollow ring (8), the hollow ring (8) is fixedly connected to the upper side of the main body (1), the hollow ring (8) is extrudedly matched with the upper flange (2), the main body (1) is provided with circumferentially uniformly distributed second communication holes (103), the second communication holes (103) are in communication with the hollow ring (8), the upper side of the main body (1) is provided with a partition table (104), the partition table (104) is provided with an annular groove, and the second communication holes (103) are in communication with the annular groove of the partition table (104). The second communication holes (103) are slidably connected with sliding columns (9) on one side close to the axis of the main body (1), the circumferentially uniformly distributed sliding columns (9) are fixedly connected with a pressure receiving ring (10) together, the pressure receiving ring (10) is slidably connected with the main body (1), and the second communication holes (103) and the hollow ring (8) are both filled with liquid.

2. A casing head having a seal as claimed in claim 1, characterised in that, The two sealing rings (7) are slidably extrudedly matched with the sliding ring (4).

3. A casing head having a seal as claimed in claim 2, wherein, The volume of the part of the sealing ring (7) embedded in the main body (1) is greater than the volume of the part of the sealing ring (7) located in the annular sliding groove (101), so as to prevent the displacement of the sealing ring (7).

4. The casing head with a sealing structure according to claim 1, characterized in that, The upper side of the pressure receiving ring (10) is lower than the upper side of the main body (1), and the upper side of the pressure receiving ring (10) is flush with the upper side of the partition table (104), so that the material leaked due to damage of the sealing gasket (6) extrudes the pressure receiving ring (10).

5. The casing head with a sealing structure according to claim 1, characterized in that, The contact area of the pressure receiving ring (10) with the leaked material is greater than the contact area of the hollow ring (8) with the leaked material.

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