Blockage removal method for gathering and transportation pipeline of oil field

Abstract

The invention discloses an oil field gathering and transportation pipeline unblocking method. The method comprises the following steps: welding the lower end of a pored short pipe at a blocked part of a gathering pipeline; the upper part of the perforated short pipe is connected with a perforated flange; the portable tapping machine is connected with the tapping flange; the portable tapping machine is started, and a hole is formed in the gathering and transportation pipeline plug; the portable tapping machine is dismantled, and the emptying flange is connected with the tapping flange; connecting one end of a liquid discharging rubber pipe to the emptying flange, and connecting the other end of the liquid discharging rubber pipe to the oil tank truck; adding water from one end of the blocked pipeline by using a pump truck, and pressurizing to flush the blocked pipeline; parts except for the trepanned short pipe are detached, and the welded pipe cap is connected with the trepanned short pipe. The special portable tapping machine has the beneficial effects that the blocked gathering and transportation pipeline can be rapidly and safely opened through the special portable tapping machine; the emptying flange and the oil tank truck are connected through the rubber pipe to form a closed space, pollution of landing oil to the environment can be effectively avoided, and environmental protection and sanitation are achieved; and the dredged gathering and transportation pipeline is quickly blocked through the welding pipe cap, so that the welding time can be shortened.

Description

Technical Field

[0001] The invention belongs to the technical field of oilfield facility maintenance and repair, and in particular relates to a method for unblocking an oilfield gathering and transportation pipeline. Background Art

[0002] In the process of oilfield production, the gathering and transportation pipeline is sometimes blocked due to the presence of impurities such as wax and silt in the gathering and transportation medium in the gathering and transportation pipeline, as well as the influence of human operation and climate and other factors, so that the gathering and transportation pipeline cannot be transported. At this time, the gathering and transportation pipeline needs to be unblocked, that is, unblocked. The current unblocking method is: dig an operating pit on the ground where the gathering and transportation pipeline is blocked to expose the gathering and transportation pipeline, use gas cutting or reciprocating saw to open a hole on the upper side of the blocked pipeline, and then use a pump truck to add water and pressurize from one end of the blocked pipeline to flush the blocked pipeline, and use high-pressure water to squeeze the dead oil in the blocked pipeline from the opening and discharge it into the operating pit until the gathering and transportation pipeline is unblocked, then weld and seal the opening, and finally backfill the operating pit. However, this method has the following disadvantages in its application: First, after the hole is opened, the high-pressure flushing of the pump truck will directly spray the dead oil in the gathering and transportation pipeline from the opening to the working pit, which will obviously cause pollution to the on-site environment; second, after the gathering and transportation pipeline is unblocked, when the opening is welded and blocked, the remaining pressure in the gathering and transportation pipeline has nowhere to be released during the flushing of the pump truck, and can only flow out from the opening. At the same time, the dead oil in the gathering and transportation pipeline that is located in front of the blockage but has not been unblocked this time will also return to the opening, resulting in long welding time or repeated welding, which brings great difficulties to the final repair welding work. Third, the existing hole-opening machine is bulky and requires large equipment such as cranes to be transported to the site, causing damages in the crop field, so it is extremely inconvenient to operate.

[0003] Chinese patent application No. 201310334409.2 discloses a method for unblocking oilfield pipelines. The method comprises the following steps: firstly, the location of pipeline blockage is roughly determined by folding method, then the location of pipeline blockage is accurately determined by sedimentation method and season method, and finally, heating method, perforation flushing method and chemical unblocking method are respectively adopted for unblocking oilfield pipelines according to different types of blockages. The advantage of this method is that it solves the problem that the prior art unblocking of oilfield pipelines is highly targeted and the specific blockage location cannot be determined, which makes implementation difficult. It has strong systematicity and is applicable to unblocking of most oilfield pipelines. Different blockages correspond to different unblocking methods, and the blocked oilfield pipelines can be unblocked quickly, ensuring the normal operation of production and improving production efficiency.

[0004] Chinese patent application No. 201721881137.8 discloses a protective cover for purging and unblocking an oil collection pipeline. The protective cover includes: a guide cylinder, an anti-diffusion cover, a fixed plate, a plurality of first connecting members, and a plurality of second connecting members; the lower end of the first connecting member is connected to the outer wall of the guide cylinder, and the upper end is detachably connected to the top wall of the anti-diffusion cover, the upper part of the guide cylinder is located inside the anti-diffusion cover, and there is a pressure relief gap between the guide cylinder and the side wall of the anti-diffusion cover; the second connecting member is detachably connected to the wall of the guide cylinder, and the lower end is detachably connected to the plate surface of the fixed plate, and a space for clamping the target oil collection pipeline is formed between the bottom of the guide cylinder and the fixed plate. The use of the protective cover can make the blockage flow downward, with a good pressure relief effect, avoiding environmental pollution and the safety hazards caused by it, and the protective cover can be firmly fixed on the target oil collection pipeline to avoid it from being separated from the target oil collection pipeline when the high-pressure blockage is sprayed out.

[0005] However, the above-mentioned prior art cannot avoid the pollution of the fallen oil and cannot improve the efficiency of unblocking from the perspective of functional structure. Summary of the invention

[0006] In order to solve the above problems, the object of the present invention is to provide a method for unblocking an oilfield gathering and transportation pipeline.

[0007] In order to achieve the above object, the method for unblocking an oilfield gathering and transportation pipeline provided by the present invention comprises the following steps performed in sequence:

[0008] 1) Dig a working pit on the ground where the gathering and transportation pipeline is blocked to expose the gathering and transportation pipeline, and then weld the lower end of a short pipe with an opening to the circumferential surface on the upper side of the blocked part of the gathering and transportation pipeline;

[0009] 2) A hole flange is threadedly connected to the upper part of the hole short pipe;

[0010] 3) Connect the bottom flange on the portable tapping machine with the flange on the tapping flange with bolts, and install a sealing gasket between the two to ensure good sealing and control the residual pressure;

[0011] 4) Turn on the portable hole-opening machine and use the drill bit that passes through the hole-opening flange and the center hole of the hole-opening short pipe to form an opening on the circumferential surface above the blocked part of the gathering and transportation pipeline;

[0012] 5) Dismantle the portable hole tapping machine and remove the pipe piece cut from the hole. Then connect the flange on the vent flange with the flange on the hole flange with bolts, and install a sealing gasket between the two to ensure good sealing. A quick connector is provided on the outside of the flange short pipe on the vent flange.

[0013] 6) Connect one end of the drain hose to the quick connector of the drain flange, and the other end to the tank truck;

[0014] 7) Use a pump truck to add water and pressurize from one end of the blocked pipeline to flush the blocked pipeline, and use high-pressure water to discharge the dead oil in the blocked pipeline into the tank truck through the perforated short pipe, perforated flange, vent flange and drain hose in sequence until all the dead oil in the gathering and transportation pipeline is discharged and water is seen;

[0015] 8) Remove all parts except the perforated short pipe, connect the internal thread on the welding pipe cap with the external thread on the perforated short pipe, and after ensuring the seal, weld the welding pipe cap and the perforated short pipe together to complete the unblocking of the blocked pipeline, and finally backfill the working pit.

[0016] In step 1), the lower end of the perforated short pipe is saddle-shaped to match the circumferential surface of the gathering and transportation pipeline, and an external thread is formed on the upper outer circumferential surface;

[0017] In step 2), the lower part of the perforated flange is a flange short tube, and the upper part is a flange plate. The inner circumferential surface of the flange short tube is provided with an internal thread that matches the external thread on the upper part of the perforated short tube to ensure sealing;

[0018] In step 3), the portable hole opening machine includes: a sealing system, a pressure control system, a cutting system, a force transmission system, a star-shaped reduction mechanism and a motor; wherein the sealing system includes a sealing shell, a bottom flange, an upper flange and a partition; the upper flange and the bottom flange are respectively arranged at the upper and lower ends of the sealing shell; the partition is located in the middle of the sealing shell, thereby dividing the upper and lower parts of the sealing shell into a sealing chamber and a pressure control chamber, and a central hole is formed in the middle of the partition; and a pressure control interface is formed on the side of the pressure control chamber;

[0019] The pressure control system includes: a pressure control housing, a piston, a spring and a sealing bolt; the inner end of the pressure control housing is threadedly connected to the pressure control interface of the sealing system, and a pressure control port is formed on one side of the middle part; the central hole of the pressure control housing is composed of a small-diameter oil discharge chamber located on the inner side and a large-diameter pressure control chamber located on the outer side, thereby forming a step at the connection between the small-diameter oil discharge chamber and the large-diameter pressure control chamber; the pressure control port is located on the large-diameter pressure control chamber near the step; the piston is a nail-shaped structure composed of a piston head and a piston rod, the piston head is movably arranged in the large-diameter pressure control chamber, and the outer side of the piston rod is located outside the pressure control housing; the spring is sleeved on the inner side of the piston rod, thereby pressing the piston head against the step; the central hole of the sealing bolt is sleeved on the outer side of the piston rod, and the external thread is connected to the outer port of the pressure control housing to seal the spring.

[0020] The force transmission system includes: a force transmission rod, a sealing ring, a sealing gland, a sealing gasket, a guide device, a displacement control cylinder and a double-acting sleeve; wherein the guide device includes a lower flange, a fixed cylinder, a guide cylinder and an upper flange; the guide cylinder is arranged inside the fixed cylinder in a concentric manner; the upper flange is arranged at the upper end of the fixed cylinder; the lower flange is arranged at the lower end of the fixed cylinder and the guide cylinder, and is connected to the upper flange of the sealing system by bolts, and a sealing gasket is arranged between the lower flange and the upper flange; the upper part of the force transmission rod is located in the guide cylinder, the upper end is a regular hexagonal prism structure, and the lower part is provided with a sealing gland and a sealing gasket on the outside, and the sealing gland and the sealing gasket are located in the sealing system The sealing chamber is in the sealing chamber, and the external thread on the sealing gland is connected with the internal thread on the upper end of the sealing chamber; the lower end of the force transmission rod passes through the central hole on the partition and is located in the pressure control chamber of the sealing system; the displacement control cylinder is in the shape of a box cover, a central circular hole for penetrating the upper end of the force transmission rod is formed in the middle of the top surface, the outer peripheral surface is a regular hexagonal prism structure, and the lower end is inserted into the annular space between the fixed cylinder and the guide cylinder and is threadedly connected with the guide cylinder; the double-acting sleeve is also in the shape of a box cover, a regular hexagonal central hole for penetrating the upper end of the force transmission rod is formed in the middle of the top surface, the inner peripheral surface is a regular hexagonal prism structure, and is fixed to the outer upper part of the displacement control cylinder;

[0021] The cutting system includes: a positioning center drill, a stopper rod and a hole drill; the upper end of the positioning center drill is connected to the lower end of the force transmission rod, the upper part is located in the pressure control chamber, and the middle and lower parts protrude outside the bottom flange; a spiral is formed on the outer circumferential surface of the lower part of the positioning center drill; the center hole on the hole drill is fixed to the middle part of the positioning center drill, and the part of the positioning center drill located between the hole drill and the spiral is a flat plate-like structure, and a stopper rod setting hole is formed in the middle part of the flat plate-like structure along the thickness direction; the stopper rod is a U-shaped structure, the middle part is inserted into the stopper rod setting hole, the two ends are located outside the stopper rod setting hole, and the maximum distance between the two ends is less than the diameter of the positioning center drill;

[0022] The output end of the motor is connected to the upper end of the force transmission rod through a star-shaped reduction mechanism. At the same time, the flange at the lower end of the star-shaped reduction mechanism is connected to the upper flange of the guide device by bolts, and a sealing gasket is provided between the flange at the lower end of the star-shaped reduction mechanism and the upper flange of the guide device.

[0023] The oilfield gathering and transportation pipeline unblocking method provided by the present invention has the following beneficial effects:

[0024] The present invention can quickly and safely open the blocked gathering and transportation pipeline through a dedicated portable hole-opening machine; connect the venting flange and the oil tanker through a hose to form a closed space, which can effectively avoid the pollution of the environment by the oil on the ground, and is environmentally friendly and hygienic; quickly seal the dredged gathering and transportation pipeline through welding pipe caps, which can shorten the welding time; the hole-opening flange and the venting flange can be reused, so the cost can be reduced. All components of the unblocking device are connected by thread or flange bolts, which ensures the rapid connection of each process. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The present invention provides a flow chart of the method for unblocking an oilfield gathering and transportation pipeline.

[0026] Figure 2 It is a cross-sectional view of the connection state of the perforated short pipe, perforated flange, sealing gasket and vent flange used in the present invention.

[0027] Figure 3 It is a cross-sectional view of the connection state of the perforated short pipe and the welded pipe cap used in the present invention.

[0028] Figure 4 This is a schematic diagram of the portable hole-opening machine used in the present invention.

[0029] Figure 5 The figure is a cross-sectional view of the overall structure of the portable hole-opening machine used in the present invention.

[0030] Figure 6 It is a three-dimensional diagram of the sealing system of the portable hole opening machine in the present invention.

[0031] Figure 7 It is a cross-sectional view of the sealing system structure of the portable hole tapping machine in the present invention.

[0032] Figure 8 It is a schematic diagram of the structure of the pressure control system of the portable hole opening machine in the present invention.

[0033] Fig. 9 It is a cross-sectional view of the pressure control system structure of the portable hole opening machine in the present invention.

[0034] Fig.10 It is a schematic diagram of the structure of the force transmission system of the portable hole opening machine in the present invention.

[0035] Fig.11 It is a cross-sectional view of the force transmission system structure of the portable hole opening machine in the present invention.

[0036] Fig.12 It is a cross-sectional view of the guide device structure of the portable hole opening machine in the present invention.

[0037] Fig.13 It is a schematic diagram of the double-acting sleeve structure of the portable hole-opening machine in the present invention.

[0038] Fig.14 It is a schematic diagram of the displacement control cylinder structure of the portable hole opening machine in the present invention.

[0039] Fig.15 It is a schematic diagram of the cutting system structure of the portable hole opening machine in the present invention.

[0040] Fig.16 It is a schematic diagram of the star-shaped reduction mechanism and motor structure of the portable hole-opening machine in the present invention. DETAILED DESCRIPTION

[0041] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0042] like Figure 1-Figure 16 As shown, the method for unblocking an oilfield gathering and transportation pipeline provided by the present invention comprises the following steps performed in sequence:

[0043] 1) digging a working pit on the ground where the gathering and transportation pipeline is blocked to expose the gathering and transportation pipeline, and then welding the lower end of a short perforated pipe 1 to the circumferential surface on the upper side of the blocked part of the gathering and transportation pipeline;

[0044] The lower port 101 of the perforated short pipe 1 is in the shape of a saddle to match the circumferential surface of the gathering and transportation pipeline, and an external thread is formed on the upper outer circumferential surface;

[0045] 2) A perforated flange 2 is threadedly connected to the upper portion of the perforated short pipe 1;

[0046] The lower part of the perforated flange 2 is a flange short tube, and the upper part is a flange plate. The inner circumferential surface of the flange short tube is provided with an internal thread that matches the external thread on the upper part of the perforated short tube 1 to ensure sealing;

[0047] 3) Connect the bottom flange on the portable tapping machine 6 to the flange on the tapping flange 2 with bolts, and install a sealing gasket 3 between the two to ensure good sealing and control the residual pressure;

[0048] The portable hole-opening machine 6 comprises: a sealing system 61, a pressure control system 62, a cutting system 63, a force transmission system 64, a star-shaped speed reduction mechanism 65 and a motor 66; wherein the sealing system 61 comprises a sealing shell 611, a bottom flange 612, an upper flange 613 and a partition 614; the upper flange 613 and the bottom flange 612 are respectively arranged at the upper and lower ends of the sealing shell 611; the partition 614 is located in the middle of the sealing shell 611, thereby dividing the upper and lower parts of the sealing shell 611 into a sealing chamber 615 and a pressure control chamber 616, and a central hole 617 is formed in the middle of the partition 614; and a pressure control interface 618 is formed on the side of the pressure control chamber 616;

[0049] The pressure control system 62 includes: a pressure control housing 621, a piston 622, a spring 623 and a plugging bolt 624; the inner end of the pressure control housing 621 is threadedly connected to the pressure control interface 618 of the sealing system 61, and an oil drain hole 6211 is formed on one side of the middle; the central hole of the pressure control housing 621 is composed of a small-diameter connector 6212 located on the inner side and a large-diameter pressure control chamber 6213 located on the outer side, thereby forming a step 6214 at the connection between the small-diameter connector 6212 and the large-diameter pressure control chamber 6213; the oil drain hole 62 11 is located on the large-diameter pressure control chamber 6213 near the step 6214; the piston 622 is a nail-shaped structure consisting of a piston head and a piston rod, the piston head is movably arranged in the large-diameter pressure control chamber 6213, and the outer side of the piston rod is located outside the pressure control housing 621; the spring 623 is sleeved on the inner side of the piston rod, thereby pressing the piston head against the step 6214; the center hole of the blocking bolt 624 is sleeved on the outer side of the piston rod, and the external thread is connected to the outer port of the pressure control housing 621 to block the spring 623.

[0050] The force transmission system 64 includes: a force transmission rod 641, a sealing ring 642, a sealing gland 643, a sealing gasket 644, a guide device 645, a displacement control cylinder 646 and a double-acting sleeve 647; wherein the guide device 645 includes a lower flange 6451, a fixed cylinder 6452, a guide cylinder 6453 and an upper flange 6454; the guide cylinder 6453 is arranged inside the fixed cylinder 6452 in a concentric manner; the upper flange 6454 is arranged at the upper end of the fixed cylinder 6452; the lower flange 6451 is arranged at the lower end of the fixed cylinder 6452 and the guide cylinder 6453, and is connected to the upper flange 613 of the sealing system 61 by bolts, and a sealing gasket 644 is arranged between the lower flange 6451 and the upper flange 613; the upper part of the force transmission rod 641 is located in the guide cylinder 6453, the upper end is a regular hexagonal prism structure, and the lower outer part is provided with a sealing gland 643 and a sealing gasket The sealing gasket 644, the sealing gland 643 and the sealing gasket 644 are located in the sealing chamber 615 of the sealing system 61, and the external thread on the sealing gland 643 is connected to the internal thread on the upper end of the sealing chamber 615; the lower end of the force transmission rod 641 passes through the center hole 617 on the partition 614 and is located in the pressure control chamber 616 of the sealing system 61; the displacement control cylinder 646 is in the shape of a box cover, and a center circular hole for penetrating the upper end of the force transmission rod 641 is formed in the middle of the top surface, and the outer peripheral surface is a regular hexagonal prism structure, and the lower end is inserted into the annular space between the fixed cylinder 6452 and the guide cylinder 6453 and is threadedly connected to the guide cylinder 6453; the double-acting sleeve 647 is also in the shape of a box cover, and a regular hexagonal center hole for penetrating the upper end of the force transmission rod 641 is formed in the middle of the top surface, and the inner peripheral surface is a regular hexagonal prism structure, which is fixed to the outer upper part of the displacement control cylinder 646;

[0051] The cutting system 63 includes: a positioning center drill 631, a stopper rod 632 and a hole drill 633; ​​the upper end of the positioning center drill 631 is connected to the lower end of the force transmission rod 641, the upper part is located in the pressure control chamber 616, and the middle and lower parts protrude outside the bottom flange 612; a spiral is formed on the outer circumferential surface of the lower part of the positioning center drill 631; the center hole on the hole drill 633 is fixed to the middle part of the positioning center drill 631, and the part of the positioning center drill 631 between the hole drill 633 and the spiral is a flat plate-like structure, and a stopper rod setting hole is formed in the middle part of the flat plate-like structure along the thickness direction; the stopper rod 632 is a U-shaped structure, the middle part is inserted into the stopper rod setting hole, is located outside the stopper rod setting hole, and the maximum distance between the two ends is smaller than the diameter of the positioning center drill 631;

[0052] The output end of the motor 66 is connected to the upper end of the force transmission rod 641 through the star-shaped reduction mechanism 65. At the same time, the flange at the lower end of the star-shaped reduction mechanism 65 is connected to the upper flange 6454 of the guide device 645 by bolts, and a sealing gasket is provided between the flange at the lower end of the star-shaped reduction mechanism 65 and the upper flange 6454 of the guide device 645.

[0053] The working principle of the portable hole-opening machine 6 is described as follows:

[0054] When it is necessary to drill a hole at a blocked part of the gathering and transportation pipeline, the construction personnel first connect the bottom flange 612 on the portable hole drill 6 with the flange plate on the hole drilling flange 2 with bolts, and install a sealing gasket 3 between the two. At this time, the lower part of the positioning center drill 631 and the hole drilling drill 633 will be located inside the hole drilling flange 2 and the hole drilling short pipe 1. Start the motor 66, and drive the positioning center drill 631 and the hole drill 633 to rotate together through the star-shaped reduction mechanism 65 and the force transmission rod 641. At the same time, the force transmission rod 641 is covered with a double-acting sleeve 647 and a displacement sleeve 646. When the force transmission rod 641 rotates, the double-acting sleeve 647 is driven to rotate. Since the inside of the double-acting sleeve 647 and the outside of the displacement sleeve 646 are both hexagonal prism structures, the displacement sleeve 646 is also driven to rotate. Since the inside of the displacement sleeve 646 and the outside of the guide tube 6453 are threaded, the displacement sleeve 646 will move downward to achieve the purpose of pushing the force transmission rod 641 forward and backward automatically, and the cutting speed is made consistent with the drill feed speed through the speed regulating device. A central circular hole is formed on the upper part of the gathering and transportation pipeline by using the positioning center drill 631. During this process, the two ends of the blocking rod 632 will be rotated upward by 90 degrees to a vertical state under the support of the edge of the central circular hole of the gathering and transportation pipeline. After the central circular hole is formed, the lower part of the positioning center drill 631 and the blocking rod 632 will enter the interior of the gathering and transportation pipeline, and then the hole-opening drill 633 will cut the gathering and transportation pipeline outside the central circular hole until a large circular hole is formed; when the blocking rod 632 enters the interior of the gathering and transportation pipeline, its two ends will lose the support of the gathering and transportation pipeline, so it will rely on gravity to flip downward by 90 degrees and become horizontal; after the large circular hole is formed, remove the bolts between the bottom flange 612 and the flange plate on the hole-opening flange 2, lift the portable hole-opening machine 6, at this time, the blocking rod 632 can bring the cut annular pipe piece out together to prevent it from falling into the gathering and transportation pipeline. After the central circular hole is formed, the collecting medium flowing out of the collecting pipeline will enter the pressure control chamber 616 of the sealed shell 611, and then flow into the small-diameter connector 6212 on the pressure control shell 621 through the pressure control interface 618. Once the pressure of the collecting medium exceeds the elastic force of the spring 623, it will push the piston 622 outward to make the piston head leave the step 6214 and compress the spring 623 at the same time. At this time, the collecting medium will be discharged outward through the oil drain hole 6211; after the pressure of the collecting medium is reduced, the piston head will rely on the elastic force of the spring 623 to reset and block the oil drain hole 6211 again.

[0055] 4) Turn on the portable hole-opening machine 6, and use a drill bit that passes through the hole-opening flange 2 and the center hole of the hole-opening short pipe 1 to form an opening on the circumferential surface above the blocked part of the gathering and transportation pipeline;

[0056] 5) Remove the portable hole tapping machine 6 and remove the pipe piece cut from the hole. Then connect the flange on the vent flange 4 with the flange on the hole flange 2 by bolts, and install a sealing gasket 3 between the two to ensure good sealing. A quick connector is provided on the outside of the flange short pipe on the vent flange 4.

[0057] 6) Connect one end of the drain hose to the quick connector of the drain flange 4, and the other end to the tank truck;

[0058] 7) Use a pump truck to add water and pressurize from one end of the blocked pipeline to flush the blocked pipeline, and use high-pressure water to discharge the dead oil in the blocked pipeline into the tank truck through the perforated short pipe 1, perforated flange 2, vent flange 4 and drain hose in sequence until all the dead oil in the gathering and transportation pipeline is discharged and water is seen;

[0059] 8) Remove all parts except the perforated short pipe 1, connect the internal thread on the welding pipe cap 5 with the external thread on the perforated short pipe 1, and after ensuring the seal, weld the welding pipe cap 5 and the perforated short pipe 1 together to complete the unblocking of the blocked pipeline, and finally backfill the working pit.

Claims

1. A method for unblocking an oilfield gathering and transportation pipeline, characterized in that: The method for unblocking an oilfield gathering and transportation pipeline comprises the following steps performed in sequence: 1) digging a working pit on the ground at the blocked part of the gathering and transportation pipeline to expose the gathering and transportation pipeline, and then welding the lower end of a short perforated pipe (1) to the circumferential surface on the upper side of the blocked part of the gathering and transportation pipeline; 2) A perforated flange (2) is threadedly connected to the upper portion of the perforated short pipe (1); 3) Connecting the bottom flange on the portable hole tapping machine (6) and the flange plate on the hole tapping flange (2) with bolts, and installing a sealing gasket (3) between the two; 4) turning on the portable hole-opening machine (6) and using a drill bit that passes through the hole-opening flange (2) and the center hole of the hole-opening short pipe (1) to form an opening on the circumferential surface above the blocked part of the gathering and transportation pipeline; 5) dismantle the portable hole opening machine (6), remove the pipe piece cut from the hole, and then connect the flange on the vent flange (4) and the flange on the hole opening flange (2) with bolts, and install a sealing gasket (3) between the two; the outside of the flange short pipe on the vent flange (4) is provided with a quick interface; 6) Connect one end of the drain hose to the quick connector of the drain flange (4), and the other end to the tank truck; 7) Use a pump truck to add water and pressurize the blocked pipeline from one end to flush the blocked pipeline, and use high-pressure water to discharge the dead oil in the blocked pipeline into the tank truck through the perforated short pipe (1), the perforated flange (2), the vent flange (4) and the drain hose in sequence until all the dead oil in the gathering and transportation pipeline is discharged and water is seen; 8) Remove all parts other than the perforated short pipe (1), connect the internal thread on the welding pipe cap (5) with the external thread on the perforated short pipe (1), and after ensuring the seal, weld the welding pipe cap (5) and the perforated short pipe (1) together, thereby completing the unblocking of the blocked pipeline, and finally backfill the working pit.

2. The method for unblocking an oilfield gathering and transportation pipeline according to claim 1, characterized in that: In step 1), the lower port (101) of the perforated short pipe (1) is saddle-shaped to match the circumferential surface of the gathering and transportation pipeline, and an external thread is formed on the upper outer circumferential surface.

3. The method for unblocking an oilfield gathering and transportation pipeline according to claim 1, characterized in that: In step 2), the lower part of the perforated flange (2) is a flange short tube, and the upper part is a flange plate. The inner circumferential surface of the flange short tube is provided with an internal thread that matches the external thread on the upper part of the perforated short tube (1).

4. The method for unblocking an oilfield gathering and transportation pipeline according to claim 1, characterized in that: In step 3), the portable hole opening machine (6) includes: a sealing system (61), a pressure control system (62), a cutting system (63), a force transmission system (64), a star-shaped speed reduction mechanism (65) and a motor (66); wherein the sealing system (61) includes a sealing shell (611), a bottom flange (612), an upper flange (613) and a partition (614); the upper flange (613) and the bottom flange (612) are respectively arranged at the upper and lower ends of the sealing shell (611); the partition (614) is located in the middle of the sealing shell (611), thereby dividing the upper and lower parts of the sealing shell (611) into a sealing chamber (615) and a pressure control chamber (616), and a central hole (617) is formed in the middle of the partition (614); and a pressure control interface (618) is formed on the side of the pressure control chamber (616); The pressure control system (62) comprises: a pressure control housing (621), a piston (622), a spring (623) and a plugging bolt (624); the inner end of the pressure control housing (621) is threadedly connected to the pressure control interface (618) of the sealing system (61), and an oil drain hole (6211) is formed on one side of the middle; the central hole of the pressure control housing (621) is composed of a small-diameter connector (6212) located on the inner side and a large-diameter pressure control chamber (6213) located on the outer side, thereby forming a step (6214) at the connection between the small-diameter connector (6212) and the large-diameter pressure control chamber (6213); the drain The oil hole (6211) is located on the large-diameter pressure control chamber (6213) near the step (6214); the piston (622) is a nail-shaped structure consisting of a piston head and a piston rod, the piston head is movably arranged in the large-diameter pressure control chamber (6213), and the outer side of the piston rod is located outside the pressure control housing (621); the spring (623) is sleeved on the inner side of the piston rod, thereby pressing the piston head against the step (6214); the center hole of the blocking bolt (624) is sleeved on the outer side of the piston rod, and the external thread is connected to the outer port of the pressure control housing (621) to block the spring (623). The force transmission system (64) comprises: A force transmission rod (641), a sealing ring (642), a sealing gland (643), a sealing gasket (644), a guide device (645), a displacement control cylinder (646) and a double-acting sleeve (647); wherein the guide device (645) comprises a lower flange (6451), a fixed cylinder (6452), a guide cylinder (6453) and an upper flange (6454); the guide cylinder (6453) is arranged inside the fixed cylinder (6452) in a concentric manner; the upper flange (6454) ) is arranged at the upper end of the fixed cylinder (6452); the lower flange (6451) is arranged at the lower ends of the fixed cylinder (6452) and the guide cylinder (6453), and is connected to the upper flange (613) of the sealing system (61) by bolts, and a sealing gasket (644) is arranged between the lower flange (6451) and the upper flange (613); the upper part of the force transmission rod (641) is located in the guide cylinder (6453), the upper end is a regular hexagonal prism structure, and the lower part is provided with a sealing gland (643) on the outside ) and a sealing gasket (644), the sealing gland (643) and the sealing gasket (644) are located in the sealing chamber (615) of the sealing system (61), and the external thread on the sealing gland (643) is connected to the internal thread on the upper end of the sealing chamber (615); the lower end of the force transmission rod (641) passes through the central hole (617) on the partition (614) and is located in the pressure control chamber (616) of the sealing system (61); the displacement control cylinder (646) is in the shape of a box cover, and a A central circular hole for penetrating the upper end of the force transmission rod (641), the outer circumference of which is a regular hexagonal prism structure, the lower end of which is inserted into the annular space between the fixed cylinder (6452) and the guide cylinder (6453) and is threadedly connected to the guide cylinder (6453); the double-acting sleeve (647) is also in the shape of a box cover, with a regular hexagonal central hole formed in the middle of the top surface for penetrating the upper end of the force transmission rod (641), the inner circumference of which is a regular hexagonal prism structure, and is fixed to the outer upper part of the displacement control cylinder (646); The cutting system (63) comprises: a positioning center drill (631), a stopper rod (632) and a hole drill (633); the upper end of the positioning center drill (631) is connected to the lower end of the force transmission rod (641), the upper part is located in the pressure control chamber (616), and the middle and lower parts protrude outside the bottom flange (612); a spiral is formed on the outer circumferential surface of the lower part of the positioning center drill (631); the center hole on the hole drill (633) is fixed to the middle part of the positioning center drill (631), and the part of the positioning center drill (631) between the hole drill (633) and the spiral is a flat plate-like structure, and a stopper rod setting hole is formed in the middle part of the flat plate-like structure along the thickness direction; the stopper rod (632) is a U-shaped structure, the middle part is inserted into the stopper rod setting hole, the two ends are located outside the stopper rod setting hole, and the maximum distance between the two ends is less than the diameter of the positioning center drill (631); The output end of the motor (66) is connected to the upper end of the force transmission rod (641) through the star-shaped reduction mechanism (65), and the flange at the lower end of the star-shaped reduction mechanism (65) is connected to the upper flange (6454) of the guide device (645) by bolts, and a sealing gasket is provided between the flange at the lower end of the star-shaped reduction mechanism (65) and the upper flange (6454) of the guide device (645).

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