A pigging adapter and pigging aid

Abstract

The utility model relates to the drilling technical field of soil layer or rock, concretely relates to a pigging joint and pigging auxiliary device. The device includes the blow-off pipeline for discharging impurities, one end of the blow-off pipeline is equipped with the pigging joint, the pigging joint includes the cylinder, the inner hole wall of the cylinder is equipped with the ball stopping board for stopping the pigging ball, the ball stopping board is equipped with the blow-off hole, and the blow-off hole is smaller than the diameter of the pigging ball to prevent the pigging ball from passing, the inlet end of the cylinder is equipped with the oil pipe interface for connecting with the coiled tubing, and the outlet end opposite to the inlet end is equipped with the blow-off pipe interface for connecting with the blow-off pipeline. The device of the utility model can not only complete the receiving work of the pigging ball and the blow-off work of the impurities such as the oil stains generated in the cleaning deposit or liquid nitrogen blowing operation, but also can deal with the situation that the pigging ball cannot flow smoothly and return in the pigging operation, has high adaptability and simple structure.

Description

Technical Field

[0001] This utility model relates to the field of drilling technology for soil or rock, and specifically to a pipe cleaning joint and a pipe cleaning auxiliary device. Background Technology

[0002] Coiled tubing is a type of tubing made of low-carbon alloy steel. It has excellent flexibility and is also known as flexible tubing. It can be wound on large-diameter drums. This type of coiled tubing has high strength and high toughness. The length of a single tube can reach several kilometers without joints. It is widely used in oilfield drilling, fracturing, fluid drainage, well workover, and unblocking of gathering and transportation pipelines. It has advantages such as the ability to operate under pressure, continuous tripping, small equipment size, and fast operation cycle.

[0003] During routine maintenance of coiled tubing or before coaxial drilling operations begin at the well site, a cleaning operation is typically performed to remove accumulated fluid, impurities, waxy deposits, or other obstructions that may affect fluid flow. Cleaning prevents corrosion or rupture caused by deposits and restores the tubing's original inner diameter, minimizing its impact on fluid velocity and improving transport efficiency. The cleaning ball is the core tool in this operation. During cleaning, the cleaning ball is first inserted into the beginning of the coiled tubing and then propelled by fluid pressure. This process cleans deposits from the tubing's inner wall. Simultaneously, monitoring equipment continuously monitors pressure and flow changes within the tubing, as well as the cleaning ball's position and status, to ensure the cleaning process proceeds smoothly. Finally, a receiving device at the end of the coiled tubing receives and temporarily stores the cleaning ball. In current technology, a sand-flush head is typically used as the receiving device. This head can quickly connect to the end of the tubing and receive the cleaning ball, and it can withstand the high pressure and high-speed flow of the fluid inside the tubing.

[0004] Secondly, during the cleaning operation of coiled tubing, special situations may occur where the coiled tubing is deformed or there are foreign objects inside the coiled tubing causing the inner diameter to decrease. In this case, the cleaning ball cannot continue to move through the reduced diameter of the coiled tubing. Furthermore, since the coiled tubing is relatively long, the cleaning ball cannot simply return by inverting the coiled tubing. Therefore, it is necessary to remove the sand-flushing head and connect it to the pump truck. The pump truck then pumps fluid in reverse to push the cleaning ball back.

[0005] In addition, after the daily pressure test of the coiled tubing is completed or the well site construction is completed, liquid nitrogen purging is required to remove oil, water or other impurities that may have been generated during the pressure test or construction. During the liquid nitrogen purging process, a pipe is usually connected to the end of the coiled tubing to discharge the fluid into a designated discharge point.

[0006] During the use of coiled tubing, a cleaning operation is typically performed first to remove deposits and other impurities from the inside of the tubing, ensuring its unobstructed flow. Then, liquid nitrogen purging is conducted to remove oil stains from the inner walls of the tubing, ensuring its cleanliness. If an abnormal situation occurs where the cleaning ball cannot flow, a pump truck is needed to push the cleaning ball back. However, whether connecting the sewage pipe after cleaning or connecting the pump truck in case of an abnormal situation, the sand-flush head receiving the cleaning ball must be disassembled before subsequent connections can be made. This repeated disassembly and assembly is cumbersome and reduces work efficiency. Furthermore, the sand-flush head, acting as a receiving device during cleaning, cannot be connected to the sewage pipe, causing fluid from the cleaning operation to be discharged onto the ground, resulting in environmental pollution.

[0007] Therefore, a device is needed that can not only receive the pigging ball during pipeline cleaning operations, but also meet the needs of connecting the sewage pipe during hydraulic purging operations, and at the same time handle the reverse pumping of the pigging ball in case of abnormal situations. Utility Model Content

[0008] The purpose of this utility model is to provide a pipe cleaning connector and a pipe cleaning auxiliary device, which can not only complete the receiving work of the pipe cleaning ball in the pipe cleaning operation, but also meet the needs of connecting the sewage pipe in the hydraulic purging operation.

[0009] To achieve the above objectives, the pigging connector of this utility model adopts the following technical solution:

[0010] A pigging connector includes a cylindrical body. The inner wall of the cylindrical body is provided with a baffle plate for blocking the pigging ball. The baffle plate is provided with a drain hole, and the drain hole is smaller than the diameter of the pigging ball to prevent the pigging ball from passing through. The inlet end of the cylindrical body is provided with a tubing interface for connecting to a continuous tubing, and the outlet end opposite to the inlet end is provided with a drain pipe interface for connecting to a drain pipe.

[0011] Furthermore, the drain hole includes a central hole located at the center of the baffle plate and side holes arranged around the central hole, wherein the diameter of the central hole is smaller than the diameter of the cleaning ball.

[0012] Furthermore, the oil pipe interface is an internally threaded section arranged on the inner wall of the cylinder.

[0013] Furthermore, the internal thread segment is a truncated tapered internal thread segment, and the relatively smaller diameter opening end of the truncated tapered internal thread segment is close to the ball-stopping plate.

[0014] Furthermore, the sewage pipe interface is an external threaded section arranged on the outer side wall of the cylinder.

[0015] Furthermore, a sealing groove is provided at the outlet end of the inner wall of the cylinder, and a sealing gasket for sealing and mating with the corresponding joint is provided in the sealing groove.

[0016] Furthermore, the outer wall of the cylinder is provided with an anti-rotation structure for the pipe wrench to clamp the cylinder.

[0017] Furthermore, the anti-rotation structure is double-flat.

[0018] Furthermore, the sewage pipe interface also serves as the pump truck interface.

[0019] Beneficial Effects: The pigging connector of this utility model is a pioneering invention. The pigging connector of this utility model includes a cylindrical body, on the inner wall of which a ball-blocking plate is provided. When the pig moves to the end of the coiled tubing, the ball-blocking plate stops the pig, thus completing the receiving of the pig. Then, it connects to a drain pipe through a drain outlet interface to discharge sediments removed during pigging operations or impurities removed during liquid nitrogen purging operations to a designated discharge point. Therefore, this device can not only receive pigs but also meet the needs of draining waste during liquid nitrogen purging operations, exhibiting high adaptability and a simple structure.

[0020] To achieve the above objectives, the pigging auxiliary device of this utility model adopts the following technical solution:

[0021] A pipe cleaning auxiliary device includes a sewage pipe for discharging impurities. One end of the sewage pipe is provided with a pipe cleaning connector. The pipe cleaning connector includes a cylinder. The inner wall of the cylinder is provided with a baffle plate for blocking the pipe cleaning ball. The baffle plate is provided with a sewage discharge hole, which is smaller than the diameter of the pipe cleaning ball to prevent the pipe cleaning ball from passing through. The inlet end of the cylinder is provided with a tubing interface for connecting to a coiled tubing, and the outlet end opposite to the inlet end is provided with a sewage pipe interface for connecting to the sewage pipe.

[0022] Furthermore, the drain hole includes a central hole located at the center of the baffle plate and side holes arranged around the central hole, wherein the diameter of the central hole is smaller than the diameter of the cleaning ball.

[0023] Furthermore, the oil pipe interface is an internally threaded section arranged on the inner wall of the cylinder.

[0024] Furthermore, the internal thread segment is a truncated tapered internal thread segment, and the relatively smaller diameter opening end of the truncated tapered internal thread segment is close to the ball-stopping plate.

[0025] Furthermore, the sewage pipe interface is an external threaded section arranged on the outer side wall of the cylinder.

[0026] Furthermore, a sealing groove is provided at the outlet end of the inner wall of the cylinder, and a sealing gasket for sealing and mating with the corresponding joint is provided in the sealing groove.

[0027] Furthermore, the outer wall of the cylinder is provided with an anti-rotation structure for the pipe wrench to clamp the cylinder.

[0028] Furthermore, the anti-rotation structure is double-flat.

[0029] Furthermore, the sewage pipe interface also serves as the pump truck interface.

[0030] Beneficial Effects: The pigging auxiliary device of this utility model is a pioneering invention. This pigging auxiliary device uses a pigging connector, which includes a cylindrical body. A ball-blocking plate is provided on the inner wall of the cylindrical body. When the pigging ball moves to the end of the coiled tubing, the ball-blocking plate stops the pigging ball, thus completing the receiving work. Then, it connects to a sewage pipe through a sewage outlet interface to discharge the sediment removed during pigging operations or the impurities removed during liquid nitrogen purging operations to a designated discharge point. Therefore, this device can not only complete the receiving work of the pigging ball but also meet the sewage discharge requirements of liquid nitrogen purging operations, exhibiting high adaptability and a simple structure. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of one embodiment of the pipe cleaning connector and pipe cleaning auxiliary device of this utility model.

[0032] In the diagram: 1. Cylinder; 2. Ball baffle; 3. Center hole; 4. Side hole; 5. Frustum tapered internal thread section; 6. External thread section; 7. Sealing gasket groove; 8. Sealing gasket; 9. Double flat. Detailed Implementation

[0033] The features and performance of this utility model will be further described in detail below with reference to the embodiments.

[0034] An embodiment of the pigging connector of this utility model is as follows:

[0035] The pigging connector of this utility model uses a baffle plate to stop the pigging ball to complete the receiving work, and then uses the interfaces at both ends of the cylinder to install the continuous oil pipe and the sewage pipe or pump truck. The connection between the oil pipe interface and the continuous oil pipe can be used for different working conditions without disassembly, which improves the adaptability of the device.

[0036] Based on the above inventive concept, as a basic solution, such as Figure 1As shown, the pigging connector of this utility model includes a cylindrical body 1. The inner wall of the cylindrical body 1 is provided with a baffle plate 2 for stopping the pigging ball. The baffle plate 2 has a drain hole, which allows impurities generated during the pigging operation or liquid nitrogen purging operation to pass through. The drain hole is smaller than the diameter of the pigging ball to prevent the pigging ball from being discharged through the drain hole and rendering the receiving operation ineffective. The pigging ball moves under the pressure of the gas or liquid filling the coiled tubing and completes the cleaning of deposits inside the coiled tubing. When the coiled tubing is basically unobstructed, the pigging ball will continue to move to the end of the coiled tubing until it is stopped by the baffle plate 2, thus completing the cleaning process. The receiving function of the pigging ball is achieved through a pipe interface at the inlet end of the cylinder 1 for connecting to the coiled tubing, and a drain pipe / pump truck interface at the outlet end opposite the inlet end for connecting to a drain pipe / pump truck. When connected to a drain pipe, this interface facilitates the discharge of sediments and other impurities to a designated discharge point during the pigging ball's cleaning of the coiled tubing. It also allows for the discharge of residual gas or liquid used to propel the pigging ball after cleaning, preventing direct discharge onto the ground and environmental pollution. Another application is during liquid nitrogen purging of the coiled tubing, where oil and other impurities generated during purging can be discharged to a designated discharge point. Therefore, this device can not only receive the pigging ball during pigging operations but also meet the drainage requirements of liquid nitrogen purging operations. Furthermore, the connection between the pipe interface at the inlet end of the cylinder 1 and the coiled tubing requires minimal disassembly, significantly improving the device's adaptability and flexibility. The device's simple structure, allowing for easy loading and unloading via the interfaces at both ends, helps shorten installation time and improve production efficiency.

[0037] In a preferred embodiment, the drain hole includes a central hole 3 located at the center of the baffle plate 2 and side holes 4 arranged around the central hole 3. The diameter of the central hole 3 is smaller than the diameter of the pigging ball. During the pigging operation, before the pigging ball reaches the end of the coiled tubing, the central hole 3 and the side holes 4 around it can be used to discharge sediments and other impurities generated during the pigging process. When the pigging ball moves to the end of the coiled tubing and enters the cylinder 1, since the diameter of the central hole 3 is smaller than the diameter of the pigging ball, the central hole 3 will jam the pigging ball to prevent it from continuing to move and complete the receiving work. At this time, the side holes 4 around the central hole 3 will continue to discharge the residual fluid used to push the pigging ball, which helps to prevent the fluid from accumulating in the coiled tubing.

[0038] In a preferred embodiment, the tubing interface is an internally threaded section arranged on the inner wall of the cylinder 1. Generally, when the tubing interface is connected to the continuous tubing, a connector is also installed on the continuous tubing, and then connected to the tubing interface of the device through the connector. The connectors available on the market are usually set as externally threaded sections 6 at one end. Therefore, setting the tubing interface as an internally threaded section not only helps to connect with the connector of the continuous tubing, but also improves the compatibility of the device's connection interface. Threaded connections offer high connection strength and can withstand significant loads. When the tubing interface and the coiled tubing connector are tightened together via threads, the thread's stability ensures a durable and stable connection. Furthermore, the threaded fit facilitates installation and disassembly; tightening and loosening can be easily accomplished using common tools such as pipe wrenches. Moreover, thread processing is highly standardized, generally adhering to national standards. Therefore, the connectors for this device and the coiled tubing can be sourced from different suppliers, reducing procurement costs and avoiding over-reliance on a single supplier. In other embodiments, quick-connect couplings can be used to connect the device to the coiled tubing. Quick-connect couplings are connectors that allow for rapid connection and disconnection, typically used in fluid transmission systems. They offer advantages such as quick connection and easy disassembly, making them suitable for applications requiring frequent connection and disconnection. Compared to the threaded connection in this preferred embodiment, although the interface connector has lower compatibility, it still allows for quick connection between the device and the coiled tubing.

[0039] In a preferred embodiment, the internal thread segment is a truncated tapered internal thread segment 5, and the relatively smaller diameter opening end of the truncated tapered internal thread segment 5 is close to the ball baffle 2. This design not only helps the cleaning ball to fall smoothly into the center hole 3 of the ball baffle 2 to complete the receiving work, but also reduces the processing difficulty of the internal thread segment, thereby shortening the processing time and reducing the processing cost. In other embodiments, the internal thread segment is not set as a truncated tapered internal thread segment 5, but is kept as a cylindrical internal thread segment.

[0040] In a preferred embodiment, the drain pipe interface is an externally threaded section 6 arranged on the outer wall of the cylinder 1. Setting the drain pipe interface as an externally threaded section 6 has essentially the same effect as an internally threaded oil pipe interface. Furthermore, when connecting the drain pipe interface to the drain pipe, a female connector can be provided at the end of the drain pipe for connection. The female connector typically has an embedded threaded section that can tightly engage with the externally threaded section 6, forming a stable connection unit and ensuring the sealing of the connection between the two, thus helping to prevent fluid leakage. A rigid pipe can be used for the drain pipe, as it can withstand the high pressure of nitrogen purging, thereby reducing the risk of personnel injury and equipment damage caused by excessive nitrogen impact. In other embodiments, instead of connecting the drain pipe and the drain pipe interface through a female connector, an internally threaded section is directly provided at the end of the drain pipe to mate with the drain pipe interface. This design increases the diameter of the drain pipe, leading to increased material costs, but it can also be considered a reliable connection method.

[0041] In a preferred embodiment, a sealing groove 7 is provided at the lower end of the inner wall of the cylinder 1. A sealing gasket 8 is provided in the sealing groove 7 for sealing and mating with the corresponding joint. When the sewage pipe is connected to the sewage pipe interface, the design of the sealing gasket can form a good seal between the two, which helps to prevent fluid leakage and thus improves the reliability of the connection position. In other embodiments, flanges are respectively provided at the end of the sewage pipe and the lower end of the cylinder 1. The flange connection replaces the threaded connection with the female head. The flange connection also has the advantages of good connection sealing and convenient installation.

[0042] In a preferred embodiment, the outer wall of the cylinder 1 is also provided with an anti-rotation structure for the pipe wrench to clamp the cylinder 1. When the oil pipe interface and the connector of the continuous oil pipe are connected by a threaded engagement, or when the drain pipe interface and the drain pipe are connected by a threaded engagement, the tightening or loosening work can be completed more easily and effortlessly with the help of a pipe wrench or other tightening tools. The anti-rotation structure makes it easier for the pipe wrench to clamp the pipe, reduces the time required for tightening the threads, improves the stability of the installation or disassembly work, and also helps to prevent the pipe wrench from slipping. The anti-rotation structure is a double flat 9, which is relatively simple to process and The double flat 9 has a large planar area and high flatness, which can increase the contact area between the cylinder 1 and the pipe wrench. In addition, since the double flat 9 has a large contact area with the pipe wrench, it can accommodate pipe wrenches of different specifications. This allows the installer to select the appropriate pipe wrench according to actual needs, improving the flexibility and convenience of the work. In other embodiments, the anti-rotation structure can also be ribs or protrusions provided on the outer wall of the cylinder 1. These ribs or protrusions should have sufficient width and height so that the pipe wrench can clamp stably. This can also achieve a close contact and cooperation with the pipe wrench to complete the purpose of tightening or loosening the threads.

[0043] In a preferred embodiment, the drain pipe interface also serves as a pump truck interface. When encountering abnormal situations during pipe cleaning operations, such as deformation of the coiled tubing or foreign objects inside the coiled tubing causing a reduction in inner diameter, the drain pipe interface can also serve as a pump truck interface and be connected to the pump truck to pump fluid in reverse, apply pressure to the cleaning ball, and cause the cleaning ball to return. This can solve the problem that the cleaning ball cannot pass smoothly through the reduced diameter of the coiled tubing and cannot return.

[0044] The specific usage process of this utility model's pigging connector is as follows: Figure 1 As shown, the truncated tapered internal thread section 5 at the upper end of the device is tightened to the connector installed on the coiled tubing. Next, a drain pipe with a certain degree of hardness is connected to the drain pipe interface. A sealing gasket 8 ensures a good seal between the drain pipe and the drain pipe interface to prevent fluid leakage. Then, the female connector at the end of the drain pipe is tightened to the external thread section 6 on the cylinder. At this point, the drain pipe can be used to discharge sediment during pipe cleaning operations or to push the fluid from the pipe cleaning ball to a designated discharge point. It can also be used to discharge oil, impurities, and nitrogen gas during liquid nitrogen purging operations. Secondly… In special circumstances such as deformation of the coiled tubing or the presence of foreign objects inside the coiled tubing causing a reduction in its inner diameter, the outlet port can be used as a pump truck port to connect to the pump truck and pump fluid in reverse, causing the pigging ball to return. In addition, during the pigging ball receiving process, the pigging ball can be judged to have fallen into the joint by calculating the internal volume of the coiled tubing and combining it with the volume recorded by the data acquisition software, the loud metallic impact sound emitted by the pigging ball falling on the baffle plate 2 and between the baffle plate 2, and the increase in circulating pressure after the pigging ball blocks the central hole 3 under a fixed displacement.

[0045] An embodiment of the pigging auxiliary device of this utility model is as follows:

[0046] A pipe cleaning auxiliary device includes a sewage pipe for discharging impurities, one end of which is provided with a pipe cleaning connector. An embodiment of the pipe cleaning connector has been described above and will not be repeated here.

[0047] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. The patent protection scope of the present utility model shall be determined by the claims. Similarly, any equivalent structural changes made based on the description and drawings of the present utility model shall also be included within the protection scope of the present utility model.

Claims

1. A pipeline cleaning connector, characterized in that, The device includes a cylinder, on the inner wall of which is provided a baffle plate for blocking the pigging ball. The baffle plate is provided with a drain hole, which is smaller than the diameter of the pigging ball to prevent the pigging ball from passing through. The inlet end of the cylinder is provided with a tubing interface for connecting to a continuous tubing, and the outlet end opposite to the inlet end is provided with a drain pipe interface for connecting to a drain pipe.

2. The pigging connector according to claim 1, characterized in that, The drain hole includes a central hole located at the center of the baffle plate and side holes arranged around the central hole. The diameter of the central hole is smaller than the diameter of the cleaning ball.

3. The pigging connector according to claim 1 or 2, characterized in that, The oil pipe interface is an internally threaded section arranged on the inner wall of the cylinder.

4. The pigging connector according to claim 3, characterized in that, The internal thread section is a truncated tapered internal thread section, and the smaller diameter opening end of the truncated tapered internal thread section is close to the ball-stopping plate.

5. The pigging connector according to claim 1, characterized in that, The sewage pipe interface is an external threaded section arranged on the outer wall of the cylinder.

6. The pigging connector according to claim 1 or 2, characterized in that, The inner wall of the cylinder is provided with a sealing gasket groove at the outlet end, and a sealing gasket for sealing and mating with the corresponding joint is provided in the sealing gasket groove.

7. The pigging connector according to claim 1 or 2, characterized in that, The outer wall of the cylinder is also provided with an anti-rotation structure for the pipe wrench to clamp the cylinder.

8. The pigging connector according to claim 7, characterized in that, The anti-rotation structure is double-flat.

9. The pigging connector according to claim 1 or 5, characterized in that, The sewage pipe interface also serves as the pump truck interface.

10. A pipe cleaning auxiliary device, comprising a sewage pipe for discharging impurities, wherein one end of the sewage pipe is provided with a pipe cleaning connector, characterized in that, The pigging connector is the pigging connector described in any one of claims 1-9.

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