Intelligent composite process gas well mouth blowout preventer
By introducing a sealing piston and buffer groove structure into the blowout preventer (BOP) and combining it with pressure sensor monitoring, the problems of poor buffering performance and low safety of the BOP have been solved, realizing the protection and status monitoring of wellhead equipment and improving the safe production of natural gas wells.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHINA PETROLEUM & CHEMICAL CORP
- Filing Date
- 2025-07-07
- Publication Date
- 2026-05-15
AI Technical Summary
Existing blowout preventers have poor buffering performance, resulting in damage to wellhead equipment and low safety. They also lack monitoring of internal gas pressure and impact conditions, making it difficult to assess their working status and predict potential risks.
A smart composite process gas wellhead blowout preventer was designed, comprising a blowout preventer pipe, a sealing piston, and a buffer groove. The sealing piston slides to buffer the impact of the plunger, and a pressure sensor monitors gas pressure changes in real time. It is equipped with a buffer spring and multiple sealing rings to enhance buffering and sealing performance.
It reduces wear and deformation of wellhead equipment, improves production safety and management efficiency, ensures no gas leakage, enables real-time monitoring and early warning of blowout preventer status, extends equipment life, and reduces maintenance costs.
Smart Images
Figure CN224244840U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the technical field of natural gas extraction, specifically to an intelligent composite process wellhead blowout preventer. Background Technology
[0002] In natural gas well development, to increase natural gas production, it is necessary to drain the fluid accumulated at the bottom of the well. Currently, one method for draining this fluid is the plunger lift method. The plunger consists of a central shaft and gaskets surrounding it. The gaskets, under the action of elastic elements, contact and rub against the wellbore wall, forming a seal. With the well shut in, the plunger descends to the bottom of the well. When the well is opened, the pressure generated by the fluid below the plunger drives it upwards, lifting the fluid above it and draining the accumulated fluid as the plunger reaches the wellhead. During the upward movement, the plunger typically travels at a high speed, which can cause excessive impact on wellhead equipment, endangering production safety. Therefore, for natural gas wells using plunger lift technology, a blowout preventer (BOP) needs to be installed at the wellhead to buffer the plunger.
[0003] Currently, the problems with blowout preventers (BOPs) are as follows: First, the internal buffering capacity of the BOP is insufficient. When the impact force is large, it not only fails to buffer the upward-moving plunger, leading to plunger damage, but may even cause excessive impact to the wellhead equipment, resulting in serious safety accidents such as natural gas leaks and equipment failures. This greatly increases the risk of production and operation and makes it difficult to ensure production safety. Second, the lack of monitoring of the internal gas pressure and impact conditions of the BOP makes it difficult for operators to assess the working status and damage level of the BOP, and makes it impossible to predict potential risks in advance and take effective maintenance and protection measures. This seriously reduces the safety and reliability of the BOP and restricts the efficient and safe exploitation of natural gas wells. Summary of the Invention
[0004] The present invention aims to provide an intelligent composite process gas wellhead blowout preventer to solve the problems of poor buffering performance and low reliability of existing blowout preventers.
[0005] To achieve the above objectives, this utility model adopts the following technical solution: an intelligent composite process gas wellhead blowout preventer, including a blowout preventer pipe, the blowout preventer pipe having an axially extending through hole that runs vertically through the entire structure, a blowout preventer cap fixedly connected to the upper part of the blowout preventer pipe, a buffer groove provided at the lower end of the blowout preventer cap, the buffer groove being coaxial with and communicating with the through hole, the width of the buffer groove being greater than the diameter of the through hole, a sealing piston being provided inside the buffer groove, the sealing piston slidingly engaging with the groove wall of the buffer groove to divide the buffer groove into an upper detection chamber and a lower receiving chamber, an installation hole being provided on the blowout preventer cap, a pressure sensor being installed in the installation hole, and a detection hole being provided at the bottom of the buffer groove, the detection hole communicating with the installation hole.
[0006] The principle and beneficial effects of this solution are as follows: A sliding sealing piston is installed inside the blowout preventer cap at the upper end of the blowout preventer. When the plunger moves upward at high speed to the wellhead, it enters the through-hole of the blowout preventer and impacts the sealing piston. The sealing piston slides in the buffer groove, compressing the detection chamber above, forming progressive resistance, and thus consuming the kinetic energy of the plunger. By buffering the impact of the plunger, the damage to the blowout preventer, blowout preventer cap, and other wellhead equipment is reduced. This reduces wear and deformation caused by frequent impacts, thereby extending the service life of the entire wellhead blowout preventer and related equipment, reducing equipment replacement and maintenance costs, and solving the problems of poor buffering performance and low reliability of blowout preventers.
[0007] When the plunger pushes the sealing piston upward, the pressure in the detection chamber increases. The pressure sensor monitors the pressure change in real time through the detection hole. The gas pressure data obtained by the pressure sensor allows the operator to understand the working status inside the blowout preventer in a timely manner. This detection data can also be used to analyze data change trends, detect potential risks in advance and issue warnings, thereby improving the management efficiency and safety of gas well production and making the blowout preventer more intelligent.
[0008] The sliding fit between the sealing piston and the wall of the buffer groove can ensure the sealing performance between the detection chamber and the receiving chamber while buffering the impact of the plunger, preventing natural gas and other gases from leaking into the chamber, ensuring the normal operation of the blowout preventer, avoiding safety accidents caused by gas leakage, and also helping to maintain the stability of the gas pressure in the chamber and improve the accuracy of the pressure sensor monitoring data.
[0009] The width of the buffer groove is greater than the diameter of the through hole. When the high-speed upward-moving plunger enters the buffer groove, it is equivalent to a sudden increase in the movement space, which can reduce the speed of the plunger to a certain extent. At the same time, it ensures that the piston moves within its safe stroke and avoids falling off.
[0010] Preferably, a buffer spring is provided inside the receiving cavity, with one end of the buffer spring connected to a sealing piston and the other end connected to the bottom of the buffer groove.
[0011] Beneficial effects: When the high-speed upward-moving plunger enters the receiving cavity and impacts the sealing piston, the buffer spring undergoes elastic deformation, further absorbing and dispersing the impact force of the plunger. Compared with relying solely on the sliding buffer of the sealing piston, it can more effectively reduce the impact intensity of the plunger on the wellhead equipment. At the same time, the buffer spring plays a role in restraining and stabilizing the sealing piston, preventing the piston from sliding or shaking excessively, making its movement in the buffer groove more stable and controllable, enhancing buffering performance and improving system stability.
[0012] More preferably, the outer circumferential surface of the sealing piston is provided with a sealing ring.
[0013] Beneficial effects: It can fill the tiny gaps between the piston and the buffer groove wall, preventing natural gas and other gases from leaking between the detection chamber and the receiving chamber, ensuring the normal operation of the blowout preventer; and it maintains stable gas pressure in the chamber, ensuring that the pressure sensor obtains accurate data, which is helpful for judging the working status of the blowout preventer.
[0014] More preferably, the sealing ring includes a ring body, on which a plurality of sealing rings extending outward toward the diameter of the sealing piston are provided.
[0015] Beneficial effects: Multiple sealing rings can form multiple sealing contact points or surfaces with the wall of the buffer groove, and can disperse the frictional force between them and the wall of the buffer groove, resulting in better sealing performance compared with a single sealing contact point structure.
[0016] Preferably, the sealing ring includes an inner sealing ring and two outer sealing rings, with the two outer sealing rings located on both sides of the inner sealing ring.
[0017] Beneficial effects: The inner sealing ring and the two outer sealing rings form a three-layer sealing defense, which greatly enhances the sealing performance; the two outer sealing rings provide lateral support to the inner sealing ring, making the entire sealing ring structure more stable. During the movement of the sealing piston, it can prevent the inner sealing ring from excessively shifting or twisting, ensuring that each sealing ring can always be tightly fitted with the buffer groove wall and the sealing piston, maintaining a good sealing state, and improving the working stability of the blowout preventer under complex working conditions.
[0018] More preferably, the extended end of the outer sealing ring is an arc-shaped surface, and an annular groove with a trapezoidal cross-section is provided between the outer sealing ring and the inner sealing ring, so that the thickness of the inner sealing ring gradually increases in the radial direction.
[0019] Beneficial effects: The extended end of the outer sealing ring is arc-shaped, which is easy to deform during extrusion. It adapts to the roughness changes of the buffer groove wall, and can better fit with the buffer groove wall to form a more reliable seal. The annular groove with a trapezoidal cross section between the outer sealing ring and the inner sealing ring makes the thickness of the inner sealing ring gradually increase in the radial direction. This structure can cause greater deformation at the thinner extended end of the inner sealing ring under pressure, forming a reliable seal. The thicker fixed end of the ring body can enhance the strength of the inner sealing ring.
[0020] More preferably, the extended end of the inner sealing ring is provided with a radially extending relief groove.
[0021] Beneficial effects: Under high pressure, the relief groove can deform the material on both sides of the relief groove to form a new sealing surface, avoiding sealing failure caused by high pressure deformation; at the same time, it can disperse the stress on the extension end of the inner sealing ring, avoid fatigue damage due to stress concentration, extend the service life of the inner sealing ring, and improve the reliability of the entire sealing ring.
[0022] Preferably, it also includes a pressure relief valve, the blowout cap is provided with a pressure relief hole, the pressure relief hole communicates with the detection hole, and the pressure relief valve is located at the outer end of the pressure relief hole.
[0023] Beneficial effects: Excess gas is discharged through the pressure relief hole, preventing safety accidents such as rupture of the detection chamber due to excessive pressure, and ensuring the safe operation of the blowout preventer and the entire gas wellhead device.
[0024] Preferably, the blowout preventer has a fastening handle on its outer side and mounting threads on its lower outer circumference.
[0025] Beneficial effects: It is securely connected to the wellhead via threads, and the fastening handle facilitates installation.
[0026] Preferably, the detection chamber is filled with an inert gas.
[0027] Beneficial effects: The compressibility of the inert gas prevents plunger rebound, ensuring a smooth stop for the plunger. Attached Figure Description
[0028] Figure 1 This is a schematic diagram of the structure of this utility model;
[0029] Figure 2 This is a cross-sectional view of the present invention;
[0030] Figure 3 This is a cross-sectional view of the sealing ring of this utility model.
[0031] The markings in the accompanying drawings include: BOP 010, BOP tube 100, mounting thread 110, fastening handle 120, through hole 130, mounting groove 140, BOP cap 200, connecting section 210, buffer groove 220, detection chamber 221, receiving chamber 222, mounting hole 230, pressure relief hole 250, sealing piston 300, sealing ring 400, ring body 410, outer sealing ring 420, arc surface 421, inner sealing ring 430, clearance groove 431, buffer spring 500, pressure relief valve 600, and pressure sensor 700. Detailed Implementation
[0032] The following detailed description illustrates the specific implementation method:
[0033] See Figures 1 to 3A smart composite process gas wellhead blowout preventer (BOP) 010 includes a blowout preventer pipe 100, which has an axially extending through hole 130 that runs vertically through the pipe. A blowout preventer cap 200 is fixedly connected to the upper part of the blowout preventer pipe 100. The connection between the blowout preventer pipe 100 and the blowout preventer cap 200 can be either threaded or interference fit. In this embodiment, an interference fit is used. Specifically, the through hole 130 of the blowout preventer pipe 100 is provided with a mounting groove 140, which has an internal thread. The lower end of the blowout preventer cap 200 is a connecting section 210 with an external thread. The lower end of the blowout preventer cap 200 extends into the mounting groove of the blowout preventer pipe 100 for threaded engagement, so that the blowout preventer cap 200 is fastened above the blowout preventer pipe 100. The lower end of the blowout preventer 200 is provided with a buffer groove 220, which is coaxial with and communicates with the through hole 130. The width of the buffer groove 220 is greater than the diameter of the through hole 130. A sealing piston 300 is provided inside the buffer groove 220, which slides in contact with the groove wall. Because the width of the buffer groove 220 is greater than the diameter of the through hole 130, the sealing piston 300 is limited by the bottom of the mounting groove when it moves downward, preventing excessive travel. The sealing piston 300 divides the buffer groove 220 into an upper detection chamber 221 and a lower receiving chamber 222. The upper end of the blowout preventer 200 is provided with a mounting hole 230, in which a pressure sensor 700 is installed. A detection hole is provided at the bottom of the buffer groove 220, which communicates with the mounting hole 230.
[0034] Preferably, an inert gas, such as nitrogen or helium, is provided in the detection chamber 221. The upward-moving plunger enters the blowout preventer 100 and collides with the sealing piston 300, pushing the sealing piston 300 upward. This increases the volume of the receiving chamber 222 and decreases the volume of the detection chamber 221, compressing the gas and increasing the gas pressure. Since the mounting hole 230 is connected to the detection chamber 221, the gas pressure in the mounting hole 230 is consistent with the gas pressure in the detection chamber 221, allowing the pressure sensor 700 to detect the pressure change in the detection chamber 221. By observing the pressure change in the detection chamber 221, the impact force between the plunger and the sealing piston 300 can be calculated, thus aiding in determining the plunger's operating status and the pressure status within the well, thereby improving the level of intelligence during natural gas well production.
[0035] Preferably, a buffer spring 500 is provided inside the receiving cavity 222. One end of the buffer spring 500 is connected to the sealing piston 300, and the other end is connected to the bottom of the buffer groove 220. The buffer spring 500 can effectively absorb the kinetic energy of the plunger, thereby improving the working safety of the intelligent composite process gas wellhead blowout preventer.
[0036] Preferably, the sealing piston 300 is a metal piston, and the metal material can be stainless steel or a nickel-based alloy.
[0037] The outer circumferential surface of the sealing piston 300 is provided with a sealing ring 400. The sealing ring 400 includes a ring body 410, on which a plurality of sealing rings extending radially outward from the sealing piston 300 are provided. In this embodiment, three sealing rings are provided: one inner sealing ring 430 and two outer sealing rings 420. The two outer sealing rings 420 are located on both sides of the inner sealing ring 430. The extended end of the outer sealing ring 420 is an arc-shaped surface 421. Due to the less material at the top of the arc-shaped surface 421, it is easy to deform during the extrusion process, adapting to the change in the roughness of the groove wall of the adaptive buffer groove 220, thus forming a more reliable seal. An annular groove with a trapezoidal cross-section is provided between the outer sealing ring and the inner sealing ring, so that the thickness of the inner sealing ring 430 gradually increases in the radial direction. This arrangement also makes the outermost radial part of the inner sealing ring 430 less material, thus making it easy to deform during the extrusion process, forming a more reliable seal. At the same time, the gradual increase in thickness can improve the overall strength of the inner sealing ring 430. The inner sealing ring 430 has a radially extending relief groove 431 at its extended end, which allows the materials on both sides of the relief groove 431 to come close to each other under high pressure to form a new sealing surface, thereby avoiding sealing failure caused by high pressure deformation.
[0038] Preferably, it also includes a pressure relief valve 600, the blowout cap 200 is provided with a pressure relief hole 250, the pressure relief hole 250 communicates with the detection hole, and the pressure relief valve 600 is located at the outer end of the pressure relief hole 250.
[0039] Preferably, the blowout preventer 100 is provided with a fastening handle 120 on its outer side and an installation thread 110 on its lower outer circumferential surface. The fastening handle 120 allows operators to easily tighten the blowout preventer 100 onto the wellhead production tree.
[0040] The above descriptions are merely embodiments of this utility model. Commonly known technical solutions and / or characteristics are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the technical solution of this utility model. These modifications and improvements should also be considered within the scope of protection of this utility model, and will not affect the effectiveness of the implementation of this utility model or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.
Claims
1. A smart composite process gas wellhead blowout preventer, characterized in that: The device includes a blowout preventer (BOP) with an axially extending through-hole. A BOP cap is fixedly connected to the upper part of the BOP, and a buffer groove is provided at the lower end of the BOP. The buffer groove is axially aligned with and communicates with the through-hole, and the width of the buffer groove is greater than the diameter of the through-hole. A sealing piston is installed inside the buffer groove, and the sealing piston slides against the groove wall to divide the buffer groove into an upper detection chamber and a lower receiving chamber. The BOP cap has a mounting hole in which a pressure sensor is installed. A detection hole is provided at the bottom of the buffer groove, and the detection hole communicates with the mounting hole.
2. The intelligent composite process gas wellhead blowout preventer according to claim 1, characterized in that: The cavity is equipped with a buffer spring, one end of which is connected to a sealing piston and the other end is connected to the bottom of the buffer groove.
3. The intelligent composite process gas wellhead blowout preventer according to claim 1, characterized in that: The outer circumferential surface of the sealing piston is provided with a sealing ring.
4. The intelligent composite process gas wellhead blowout preventer according to claim 3, characterized in that: The sealing ring includes a ring body, on which a plurality of sealing rings extending outward toward the diameter of the sealing piston are provided.
5. The intelligent composite process gas wellhead blowout preventer according to claim 4, characterized in that: The sealing ring includes an inner sealing ring and two outer sealing rings, with the two outer sealing rings located on both sides of the inner sealing ring.
6. The intelligent composite process gas wellhead blowout preventer according to claim 5, characterized in that: The extended end of the outer sealing ring is an arc-shaped surface, and an annular groove with a trapezoidal cross-section is provided between the outer sealing ring and the inner sealing ring, so that the thickness of the inner sealing ring gradually increases in the radial direction.
7. The intelligent composite process gas wellhead blowout preventer according to claim 5, characterized in that: The extended end of the inner sealing ring is provided with a radially extending relief groove.
8. The intelligent composite process gas wellhead blowout preventer according to claim 1, characterized in that: It also includes a pressure relief valve, the blowout cap is provided with a pressure relief hole, the pressure relief hole is connected to the detection hole, and the pressure relief valve is located at the outer end of the pressure relief hole.
9. The intelligent composite process gas wellhead blowout preventer according to claim 1, characterized in that: The blowout preventer has a fastening handle on its outer side and an installation thread on its lower outer circumference.
10. The intelligent composite process gas wellhead blowout preventer according to claim 1, characterized in that: An inert gas is installed inside the detection chamber.