Drill floor-free drilling plug sand washing matching system device and construction method

Abstract

The invention provides a sand washing matching system without a drill floor drilling plug and a construction technology. A circulation system is composed of a wellhead flange, a blowout preventer, an anti-overflow pool, a flow guide groove, a grit chamber, a liquid transfer pump, a minor repair circulation tank, a skid-mounted pump or pump truck, a high-pressure pipeline, a sand washing pipe column and a screw drill. The clamping device and the sliding rail device are used for achieving fixed balance of the sand washing pipe column in the plug drilling and sand washing process. The set of equipment system is light, simple and convenient to install, fully utilizes the limited characteristics of a site, controls the body type and the volume of newly-designed added equipment, is skillfully combined, ensures that the strength is large enough and the safety and environment-friendly coefficient is high, and is matched with a minor repair team, so that rapid sand drilling and washing project construction can be realized, and the purposes of increasing the speed, reducing the cost and improving the efficiency are achieved.

Description

Technical Field

[0001] The present invention relates to the field of oil engineering machinery devices, and particularly relates to a matching system device and construction method for plug drilling and sand washing without a drill floor. Background Art

[0002] The main area of Tahe Oilfield is an Ordovician ultra-deep and thick carbonate heavy oil reservoir, which uses open-hole completion. Due to the water-soluble characteristics of carbonate rocks, the stability of the open-hole section is poor, and the incidence of collapse and sand burial is high. The average annual sand washing workload is more than 50 well-times. Also, due to serious water channeling and water flooding of oil layers in the later stage of development, the workload of water shutoff and profile control is also more than 50 well-times per year. Moreover, the depth error of cement plugging is large, and the construction of plug drilling accompanied by drilling accounts for more than 80%. Coupled with the fact that wellbore plugging and drilling must be carried out together, the annual workload of plug drilling and sand washing is more than 100 well-times.

[0003] The existing technology requires a drill bit or mill shoe to be lowered for plug drilling of cement plugs or sand washing of carbonate oil layers in downhole operations to break the downhole cement or rock. A large torque will be generated during the operation. Especially in heavy oil wells with a well depth exceeding 5000 meters, it is difficult to stabilize the pipe string solely relying on the frictional force between the pipe string and the wellbore wall. Therefore, the kelly bar and rotary table of the workover drill floor are required to control the rotation, and at the same time, equipment such as a guide pipe, a flow guide groove, a vibrating screen, a circulation tank, and a mud pump are needed to circulate the well fluid for sand washing. It is necessary to rely on the workover team and workover equipment to meet the construction conditions. However, the construction of the current workover team and workover equipment faces the following problems: the relocation and installation of the workover drill floor plug drilling and sand washing equipment take a long time, the connection of the workover kelly bar and the single root for sand washing takes a long time, the workover equipment is heavy, the operation safety risk is relatively large, and the workover team has a high configuration, many personnel, slow efficiency, and high cost. Summary of the Invention

[0004] In order to solve the problems of long relocation and installation time, relatively large operation safety risk, slow efficiency, and high cost of the workover team and workover equipment, the present invention proposes a matching system and construction process for plug drilling and sand washing without a drill floor. By using a circulation system composed of a wellhead flange, a blowout preventer, a spill prevention pool, a flow guide groove, a sand settling tank, a transfer pump, a workover circulation tank, a skid-mounted pump or a pump truck, a high-pressure pipeline, a sand washing pipe string, and a positive displacement motor, the fixed balance of the sand washing pipe string during the plug drilling and sand washing process is realized by using a clamping device and a slide rail device; this set of equipment system is light, simple, and convenient to install, fully utilizes the characteristics of limited site, controls the size and volume of the newly designed equipment, combines skillfully, and at the same time ensures sufficient strength and high safety and environmental protection coefficient. Cooperating with the workover team, it can realize the construction of rapid plug drilling and sand washing projects, achieving the purpose of improving speed, reducing costs, and increasing efficiency.

[0005] The present invention provides the following specific solutions:

[0006] In a first aspect, a matching system device for plug drilling and sand washing without a drill floor includes: a circulation system and an anti-reverse system;

[0007] The described circulation system includes: a wellhead flange, a blowout preventer connected above the wellhead flange, the blowout preventer is connected to the overflow pool above through a flange connection ring, one end of the overflow pool is communicated with a sand settling tank through a diversion groove, and the sand settling tank, a transfer pump, a workover circulation tank, a skid-mounted pump or a pump truck are sequentially connected through high-pressure pipelines. The other end of the skid-mounted pump or the pump truck is connected to one end of a water hose through a high-pressure pipeline, the other end of the water hose is connected to one end of a swivel elbow, the other end of the swivel elbow is connected to a sand washing string, and the sand washing string sequentially passes through the overflow pool, the flange connection ring, the blowout preventer, and the wellhead flange and is connected to a positive displacement motor at the bottom and enters the bottom of the well through the wellhead;

[0008] The described anti-reverse system includes: a clamping device fixedly clamped on the sand washing string and a slide rail device connected to the clamping device through a steel chain;

[0009] The slide rail device includes: a slide rail with a first chute and a second chute respectively provided at the front and the back, a slider is slidably connected in the first chute, a counterweight slider is slidably connected in the second chute, the slider and the counterweight slider have the same weight and are connected by a steel wire rope. The steel wire rope bypasses a pulley at the top of the slide rail, and the slider is connected to the connection ring.

[0010] Preferably, the clamping device includes: one ends of two clamping pieces are rotatably connected through a hinge, and the other ends are fixed through fastening screws, and a connection ring is provided on the hinge.

[0011] Preferably, the included angle between the groove surface of the diversion groove and the horizontal plane is 5° - 15°.

[0012] Preferably, the sand settling tank includes: a rectangular iron pool body with internal dimensions of 4 meters in length, 3 meters in width, and 1.2 meters in height. There are 8 symmetrically arranged lifting lugs at the front and back at the bottom of the pool body, and a side door is provided near the bottom in the middle at the front.

[0013] Preferably, the clamping piece is an iron tile-shaped clamping piece, and vertical alloy clamping teeth are provided on the inner arc; the anti-torsion strength of the clamping device is 5 KN·m, and the rotation radius is 0.5 m.

[0014] Preferably, the slider is connected to the connection ring through a steel chain. When the steel chain is in a tensioned state, the included angle with the connection ring is 90°.

[0015] Preferably, both the first chute and the second chute are T-shaped chutes, the slider and the counterweight slider are respectively embedded in the first chute and the second chute, and the slider and the counterweight slider have equal weights.

[0016] Preferably, the tensile strength of the slide rail is above 5 KN.

[0017] Preferably, a workover operation platform is provided around the overflow pool.

[0018] In a second aspect, the present invention provides a construction method for a drilling platform-free drilling plug and sand flushing supporting system device, comprising:

[0019] S1. Construction Preparation: a. Move minor repair equipment into place; b. Kill the well and remove the original wellbore string; c. Remove the Christmas tree, install the blowout preventer, and conduct a pressure test; d. Install the minor repair operation platform;

[0020] S2. Circulation System Installation: a. Lower the drill string: Connect the auger, auger, and flexible elbow from bottom to top. After the auger reaches a sand surface or plug surface, lift it up 1 meter and brake the vehicle. b. Connect the flexible elbow inlet to the high-pressure pipeline and skid-mounted pump or pump truck with a water hose. Start the pump and test the pressure to ensure the pressure is stable. c. Pass a tubing through the flange connection ring and overflow tank according to the wellhead replacement method, and connect and tighten with bolts. d. Place the grit chamber to the right front of the wellhead, 4.5 meters from the wellhead. e. Connect the inlet of the diversion trough to the outlet of the overflow tank, and place the outlet of the diversion trough above the grit chamber. f. Connect the liquid transfer pump to the high-pressure pipeline and place it next to the grit chamber. Connect the outlet of the high-pressure pipeline to the inlet of the minor repair circulation tank.

[0021] S3. Anti-reversal system installation: a. Secure the slide rail assembly to the right front of the derrick, with the first chute facing the wellhead. Adjust the wire rope so that the slider and counterweight slider are both centered in the chute and at the same height. b. Clamp the clamping device onto the sandblasting string 1.5 meters above the minor repair work surface, with one end of the connecting ring facing the slide rail. Tighten the fastening screw with a wrench. c. Adjust the height of the slider in the first chute so that the slider and clamping device are on the same level. Connect the slider and clamping device with a chain.

[0022] S4. Drilling and flushing process: a. When starting the pump for circulation, the hydraulic motor at the bottom of the sand washing string drives the drill bit or milling shoe to rotate, and the sand washing string is kept balanced under the action of the clamping device and the slide rail device; c. When there is drilling and flushing footage downward, the clamping device drives the slider to move downward synchronously, and drives the wire rope and the counterweight slider, so that the counterweight slider moves an equal distance in the opposite direction to the slider; d. During the drilling and flushing process, the well fluid returns from the wellhead and enters the anti-overflow pool, and flows into the diversion trough from the outlet of the anti-overflow pool under the action of gravity, and then flows into the sand settling pool through the outlet of the diversion trough; e. When the liquid level in the sand settling pool is relatively high, start the transfer pump to transfer the well fluid to the workover circulation tank for recycling into the well again; f. During the drilling and flushing process, it is required to timely clean up the viscous oil blocks or other oil stains floating on the liquid surface in the sand settling pool; g. When the solid deposition in the sand settling pool exceeds 30% of the pool volume, stop the drilling and flushing footage, continue to circulate the well fluid until it reaches 1.2 times the wellbore volume and then stop the pump, remove the clamping device, lift the pipe feet by 20 meters, use the transfer pump to transfer all the well fluid in the sand settling pool to the workover circulation tank, clean out all the sediments at the bottom of the pool, and at the same time do a good job in environmental protection and hydrogen sulfide protection; h. After the sand settling pool is cleaned, continue to execute according to the construction process S3 and S4.

[0023] S5. Construction completion: After the drilling and flushing construction is completed, remove the following equipment: clamping device, slide rail device, diversion trough, anti-overflow pool, flange connection ring, sand settling pool.

[0024] Advantages of the present invention:

[0025] The present invention provides a matching system device and construction method for plug drilling and sand washing without a drilling platform. Through a circulation system composed of a wellhead flange, a blowout preventer, an anti-overflow pool, a diversion trough, a sand settling pool, a transfer pump, a workover circulation tank, a skid-mounted pump or a pump truck, a high-pressure pipeline, a sand washing string and a positive displacement motor, the clamping device and the slide rail device are used to realize the fixed balance of the sand washing string during the plug drilling and sand washing process; this set of equipment system is light, simple and easy to install, makes full use of the characteristics of limited site, controls the size and volume of the newly designed equipment, combines skillfully, and ensures sufficient strength and high safety and environmental protection coefficient. Cooperating with the workover team, it can realize the construction of rapid drilling and sand washing projects, achieving the purpose of speeding up, reducing costs and increasing efficiency; compared with the conventional major repair drilling platform drilling and flushing construction, it saves more than 3 days of relocation and installation time per well, the speed of adding and reducing single joints of the swivel elbow and the kelly and the rotary table is fast and safer, saving about 10 hours per well on average, the construction efficiency is greatly improved, saving more than 150,000 yuan of downhole operation costs per well, increasing the oil production time of the oil well by 4 days, increasing the benefit by more than 100,000 yuan, and the total efficiency increase per well is more than 250,000 yuan.

[0026] Specifically, a wellhead flange is added above the blowout preventer, which can compensate for the height difference between the upper plane of the blowout preventer and the workbench for workover operations. At the same time, it serves as a seal to prevent well fluid from leaking to the ground and causing pollution. When adding or removing tubing, it can also support the weight of the stuck pipe and the entire wellbore string. Since its inner diameter is not less than the maximum through-bore diameter of the blowout preventer, wellhead equipment, and wellbore, it can ensure the smooth passage of downhole tubing and tools.

[0027] Specifically, the sand settling pit is used to collect the well fluid and other returns for a long time, serving as a buffer and anti-overflow function for the circulating fluid. By relying on a sharp reduction in flow velocity, the returned solids and liquids are separated, facilitating classified collection and recycling.

[0028] Specifically, the inner arc of the clamping piece of the clamping device has vertical alloy slip teeth, which are tightly fastened by fastening screws to tightly bite and hold the tubing. The connecting ring is connected to the slide rail device through a chain. When the tubing rotates until the chain is in a tensioned state, the entire tubing string and clamping system immediately stop rotating, serving to prevent the sand washing tubing string from rotating together with the positive displacement motor.

[0029] Specifically, the slide rail device is connected to a slider and a counterweight slider of the same weight through a steel wire rope, achieving a balanced state at any height within the chute, meeting the requirement that the clamping device can be lifted and lowered freely during the drilling and sand washing process without being restricted. This not only ensures the free up-and-down movement function of the sand washing tubing string but also prevents the sand washing tubing string from being bent due to the non-perpendicularity of the chain to the sand washing tubing string, resulting in a large lateral tensile force on the sand washing tubing string, which may damage the casing and open hole by the lateral attack of the downhole drill bit, thus affecting the drilling and sand washing effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a schematic diagram of a matching system device for drill plugging and sand washing without a drill floor provided by the present invention.

[0031] Figure 2 is a top view of the slide rail device in a matching system device for drill plugging and sand washing without a drill floor provided by the present invention.

[0032] Figure 3 is a detailed structural schematic diagram of the sand settling pit in some embodiments provided by the present invention.

[0033] Figure 4 is a real scene diagram of a matching system device for drill plugging and sand washing without a drill floor in some embodiments provided by the present invention.

[0034] Figure 5 is a simple schematic diagram of a matching system device for drill plugging and sand washing without a drill floor provided by the present invention.

[0035] Figure 6 is a schematic diagram of the anti-reverse system in some embodiments provided by the present invention.

[0036] Figure 7It is a schematic diagram of the clamping device in some embodiments provided by the present invention.

[0037] Figure 8 It is a schematic diagram of the opening of the clamping device in some embodiments provided by the present invention.

[0038] In the figure: 100, circulation system; 101, flange connection ring; 102, anti-overflow pool; 103, diversion channel; 104, sand settling tank; 105, transfer pump; 106, workover circulation tank; 107, skid-mounted pump or pump truck; 108, high-pressure pipeline; 109, water hose; 110, movable elbow; 111, sand washing pipe string; 112, blowout preventer; 113, wellhead flange; 114, positive displacement motor; 1041, rectangular iron pool body; 1042, side door; 1043, lifting lug; 200, clamping device; 2001, clamping piece; 2002, fastening screw; 2003, hinge; 2004, connection ring; 300, slide rail device; 3001, slide rail; 3002, first chute; 3003, slider; 3004, pulley; 3005, steel wire rope; 3006, second chute; 3007, counterweight slider; 400, iron chain; 500, anti-reverse system; 600, workover operation platform. Detailed implementation manners

[0039] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0040] Embodiment 1:

[0041] As Figure 1 , Figure 2 shown, a matching system device for plug drilling and sand washing without a drill floor includes: a circulation system 100 and an anti-reverse system 500;

[0042] The circulation system 100 includes: a wellhead flange 113, a blowout preventer 112 connected above the wellhead flange 113, the blowout preventer 112 is connected to the upper anti-overflow pool 102 through a flange connection ring 101, one end of the anti-overflow pool 102 is communicated with the sand settling tank 104 through a diversion channel 103, and the sand settling tank 104, transfer pump 105, workover circulation tank 106, and skid-mounted pump or pump truck 107 are sequentially connected through a high-pressure pipeline 108. The other end of the skid-mounted pump or pump truck 107 is connected to one end of a water hose 109 through a high-pressure pipeline 108. The other end of the water hose 109 is connected to one end of a movable elbow 110. The other end of the movable elbow 110 is connected to a sand washing pipe string 111. The sand washing pipe string 111 sequentially passes through the anti-overflow pool 102, flange connection ring 101, blowout preventer 112, and wellhead flange 113, and is connected to a positive displacement motor 114 at the bottom, and enters the bottom of the well through the wellhead;

[0043] The anti-reversal system 500 includes: a clamping device 200 fixedly clamped on the sand washing pipe string 111 and a slide rail device 300 connected to the clamping device 200 through an iron chain 400;

[0044] The clamping device 200 includes: one ends of two clamping pieces 2001 are rotatably connected through a hinge 2003, and the other ends are fixed through fastening screws 2002. A connecting ring 2004 is provided on the hinge 2003. The clamping device 200 is fixedly clamped on the sand washing pipe string 111;

[0045] The slide rail device 300 includes: a slide rail 3001 provided with a first chute 3002 and a second chute 3006 at the front and rear respectively. A slider 3003 is slidably connected in the first chute 3002, and a counterweight slider 3007 is slidably connected in the second chute 3006. The slider 3003 and the counterweight slider 3007 have the same weight and are connected through a steel wire rope 3005. The steel wire rope 3005 bypasses a pulley 3004 at the top of the slide rail 3001, and the slider 3003 is connected to the connecting ring 2004.

[0046] Through a circulation system composed of a wellhead flange, a blowout preventer, an anti-overflow pool, a diversion groove, a sand settling tank, a transfer pump, a workover circulation tank, a skid-mounted pump or a pump truck, a high-pressure pipeline, a sand washing pipe string, and a positive displacement motor, the clamping device and the slide rail device are used to achieve the fixed balance of the sand washing pipe string during the plug drilling and sand washing process; this set of equipment system is light and simple, easy to install, makes full use of the characteristics of limited site, controls the size and volume of the newly designed equipment, combines skillfully, and ensures sufficient strength and high safety and environmental protection coefficient. Cooperating with the workover team, it can realize the construction of rapid drilling and sand washing projects, achieving the purpose of increasing speed, reducing costs and increasing efficiency.

[0047] Specifically, the clamping device 200 includes: one ends of two clamping pieces 2001 are rotatably connected through a hinge 2003, and the other ends are fixed through fastening screws 2002. The connecting ring 2004 is provided on the hinge 2003.

[0048] In some embodiments, as Figure 8 shown, the two clamping pieces are closed, tightly clamped by the fastening screws, tightly bite and hold the oil pipe. After starting the positive displacement motor, it drives the sand washing pipe string to rotate, and then drives the clamping device to rotate synchronously; use an iron chain to connect the connecting ring to the slide rail device. When the iron chain is in a tension state, the entire sand washing pipe string and the clamping device stop rotating.

[0049] Specifically, the included angle between the groove surface of the diversion groove 103 and the horizontal plane is 5° - 15°.

[0050] In some embodiments, as Figure 4As shown, the diversion chute serves as a transfer channel for the well fluid and other returned substances. Utilizing the height difference between the wellhead and the sand settling tank, the well fluid and other returned substances flow into the sand settling tank. The slope of the chute surface is 5° - 15°, to avoid a too small slope causing blockage of the channel by the returned solid substances, or a too large slope causing the liquid flow to overflow and pollute the ground. The set length is not less than 4 meters to compensate for the small space of the channel on the right side of the wellhead and the large distance between the sand settling tank and the wellhead.

[0051] Specifically, the sand settling tank 104 includes: a cuboid iron pool body 1041 with internal dimensions of 4 meters in length, 3 meters in width, and 1.2 meters in height. There are 8 symmetrically arranged lifting lugs 1043 at the front and back at the bottom of the cuboid iron pool body, and a side door 1042 is provided near the bottom in the middle of the front.

[0052] In some embodiments, as Figure 3 shown, the sand settling tank is a cuboid iron pool with a completely open top. The designed internal clear dimensions are 4 meters in length, 3 meters in width, and 1.2 meters in height respectively, and there are 8 symmetrically arranged lifting lugs at the bottom. The sand settling tank is mainly used to collect the well fluid and other returned substances for a long time, playing a role in buffering and preventing overflow of the circulating fluid. By relying on a sharp slowdown in the flow rate, the returned solid part and liquid part are separated. Among them, the heavy oil blocks or other oil stains float to the upper part of the liquid because they are lighter than the kill fluid, and the sand grains or cement chips sink to the bottom of the tank body because they are heavier than the kill fluid. The heavy oil blocks or oil stains in the upper part can be manually cleaned out at any time and sent to the storage point for recycling by a small cart. After the drilling and flushing construction is paused or completed, the liquid in the tank is transferred to the workover circulation tank by a transfer pump, and then the bottom side door is opened to clean out the sand grains or cement chips with a shovel, which are pushed away by a small cart and discharged in accordance with laws and regulations.

[0053] Specifically, the collet is an iron tile-shaped collet, and vertical alloy chuck teeth are provided on the internal arc. The anti-torque strength of the clamping device is 5 KN·m, and the rotation radius is 0.5 m.

[0054] In some embodiments, as Figure 7 、 Figure 8 shown, vertical alloy chuck teeth are provided on the internal arc of the iron tile-shaped collet. Through fastening screws, the tubing is tightly clamped and held. If the tubing rotates, it must drive the clamping device to rotate synchronously.

[0055] Specifically, the slider is connected to the connecting ring 2004 by a chain 400. When the chain 400 is in a tensioned state, the included angle with the connecting ring is 90°.

[0056] In some embodiments, as Figure 6As shown, the iron chain is connected to the connecting ring through a locking hook. If the tubing rotates until the iron chain is in a taut state, the entire pipe string and the clamping system will immediately stop rotating. When the iron chain forms a 90° angle with the clamp, the moment arm is the longest at 0.5 m and the pulling force is the smallest. Adjust the length of the iron chain to make this angle 90°, and the drilling and flushing construction will be the safest and most reliable.

[0057] Specifically, both the first chute 3002 and the second chute 3006 are T-shaped chutes. The slider 3003 and the counterweight slider 3007 are respectively embedded in the first chute 3002 and the second chute 3006, and the slider 3003 and the counterweight slider 3007 have equal weights.

[0058] In some embodiments, as Figure 2 shown, in order to ensure that the anti-rotation clamping device can move up and down freely with the pipe string during the drilling and flushing process without restrictions, a vertical slide rail device is designed. The slider is embedded in the T-shaped first chute, and a second connecting ring is provided on the slider. At the opening of the chute, the second connecting ring is connected to the iron chain. In order to prevent the square slider from falling due to gravity and affecting the anti-rotation effect, a T-shaped second chute symmetrical to the front is designed behind the slide rail, and a counterweight slider identical to the slider is embedded. The slider and the counterweight slider are connected to each other by a steel wire rope passing through the pulley at the top of the slider, and are tensioned in the chute under the action of gravity, so that the two sliders move in opposite directions, achieving the purpose of counterweighting the slider by the counterweight slider and restricting its free fall. This not only ensures the free up and down movement function of the pipe string, but also prevents the pipe string from being bent due to a large lateral pulling force caused by the non-perpendicularity of the iron chain and the pipe string, resulting in lateral attack of the downhole drill bit on the casing and open hole, thereby affecting the drilling and flushing effect. The designed tensile strength is 10 KN. The slide rail is a vertically long columnar shape, welded and processed from H-shaped steel. There is a T-shaped chute on each of the front and back sides. The T-shaped chute is lubricated to embed the slider. A fixed pulley is installed directly above the top, so that the steel wire rope passing around the fixed pulley can slide freely. The upper and middle parts of the entire slide rail are fixed to the lower part of the derrick with screws and snap rings. The lower part of the slide rail is connected to the workover rig base, and the bottom of the slide rail touches the ground and is firmly seated. The tensile strength requirement of the slide rail is above 5 KN; the front slider is connected to the iron chain and moves up and down in the first chute almost synchronously with the sand flushing pipe string; the counterweight slider is connected to the slider by a steel wire rope passing around the fixed pulley at the top of the slide rail to prevent the front slider from falling freely.

[0059] Specifically, the tensile strength of the slide rail is above 5 KN.

[0060] Specifically, a workover operation platform 600 is provided around the anti-overflow pool.

[0061] In some embodiments, the workover operation platform and the bottom of the anti-overflow pool are on the same horizontal plane, which is convenient for cleaning the anti-overflow pool on the workover operation platform. At the same time, a clamping device can be set on the sand flushing pipe string.

[0062] Embodiment 2:

[0063] The present invention provides a construction method for a matching system device of plug drilling and sand washing without a drill floor, including:

[0064] S1. Construction preparation: a. The workover equipment is moved in place; b. Kill the well and pull out the original well tubing and rod string; c. Remove the Christmas tree, install the blowout preventer and test it to be qualified; d. Install the workover operation platform;

[0065] S2. Installation of the circulation system: a. Lower the drill and sand washing string: Connect the positive displacement motor, sand washing string, and swivel elbow from bottom to top. After the positive displacement motor detects the sand surface or plug surface, lift it by 1 meter and brake; b. Connect the inlet end of the swivel elbow to the high-pressure pipeline and the skid-mounted pump or pump truck with a hose, and start the pump for pressure testing. Keep the pressure stable and qualified; c. Use a tubing to pass through the flange connection ring and the overflow pool according to the method of threading and replacing the wellhead, and connect and fasten with bolts; d. Place the sand settling tank 4.5 meters in front of the right side of the wellhead; e. Connect the inlet end of the diversion trough to the outlet of the overflow pool, and place the outlet end of the diversion trough above the sand settling tank; f. Connect the transfer pump to the high-pressure pipeline and place it beside the sand settling tank. Connect the outlet end of the high-pressure pipeline to the inlet of the workover circulation tank;

[0066] S3. Installation of the anti-reverse system: a. Fix the slide rail device in front of the right side of the derrick, with the first chute facing the wellhead direction. Adjust the wire rope so that both the slider and the counterweight slider are in the middle of the chute and at the same height; b. Clamp the clamping device on the sand washing string 1.5 meters above the workover operation table, and make one end of the connecting ring face the slide rail direction. Tighten the fastening screws with a wrench; c. Adjust the height of the slider in the first chute so that the slider and the clamping device are on the same horizontal plane, and connect the slider and the clamping device with a chain;

[0067] S4. Drilling and sand washing process: a. When starting the pump for circulation, the hydraulic motor at the bottom of the sand washing string drives the drill bit or mill to rotate. The sand washing string is kept balanced under the action of the clamping device and the slide rail device; c. When there is downward drilling and penetration, the clamping device drives the slider to move downward synchronously, and drives the wire rope and the counterweight slider, so that the counterweight slider moves an equal distance in the opposite direction to the slider; d. During the drilling and sand washing process, the well fluid returns from the wellhead, enters the overflow pool, and flows into the diversion trough from the outlet of the overflow pool under the action of gravity, and then flows into the sand settling tank through the outlet of the diversion trough; e. When the liquid level in the sand settling tank is relatively high, start the transfer pump to transfer the well fluid to the workover circulation tank for recycling into the well again; f. During the drilling and sand washing process, it is required to promptly clean up the viscous oil blocks or other oil stains floating on the liquid surface in the sand settling tank; g. When the solid deposition in the sand settling tank exceeds 30% of the tank volume, stop the drilling and penetration, continue to circulate the well fluid until it reaches 1.2 times the wellbore volume, then stop the pump, remove the clamping device, lift the pipe feet by 20 meters, use the transfer pump to transfer all the well fluid in the sand settling tank to the workover circulation tank, clean out all the sediments at the bottom of the tank, and at the same time do a good job in environmental protection and hydrogen sulfide protection; h. After the sand settling tank is cleaned, continue to execute according to the construction process S3 and S4.

[0068] S5. Construction completion: After the drilling and flushing construction is completed, remove the following equipment: clamping device, slide rail device, diversion trough, anti-overflow pool, flange connection ring, and sand settling tank.

[0069] It should be noted that the above-described specific embodiments can enable those skilled in the art to understand the present invention more comprehensively, but do not limit the present invention in any way. Therefore, although this specification has described the present invention in detail with reference to the accompanying drawings and embodiments, those skilled in the art should understand that the present invention can still be modified or equivalently replaced. In short, all technical solutions and their improvements that do not depart from the spirit and scope of the present invention should be covered by the protection scope of the present invention patent.

Claims

1. A matching system device for plug drilling and sand washing without a drilling platform, characterized in that, Comprising: A circulation system (100) and an anti-reversal system (500); The circulation system (100) includes: a wellhead flange (113), a blowout preventer (112) connected above the wellhead flange (113), the blowout preventer (112) is connected to the overflow pool (102) above through a flange connection ring (101), one end of the overflow pool (102) is communicated with a sand settling tank (104) through a diversion groove (103), the sand settling tank (104), a transfer pump (105), a workover circulation tank (106), a skid-mounted pump or a pump truck (107) are sequentially connected through a high-pressure pipeline (108), the other end of the skid-mounted pump or the pump truck (107) is connected to one end of a hose (109) through a high-pressure pipeline (108), the other end of the hose (109) is connected to one end of a swivel elbow (110), the other end of the swivel elbow (110) is connected to a sand washing string (111), the sand washing string (111) sequentially passes through the overflow pool (102), the flange connection ring (101), the blowout preventer (112), the wellhead flange (113), and is connected to a positive displacement motor (114) at the bottom, and enters the bottom of the well through the wellhead; The anti-reversal system (500) includes: a clamping device (200) fixedly clamped on the sand washing string (111) and a slide rail device (300) connected to the clamping device (200) through a chain (400); The slide rail device (300) includes: a slide rail (3001) provided with a first chute (3002) and a second chute (3006) at the front and rear respectively, a slider (3003) is slidably connected in the first chute (3002), a counterweight slider (3007) is slidably connected in the second chute (3006), the slider (3003) and the counterweight slider (3007) have the same weight and are connected by a steel wire rope (3005), the steel wire rope (3005) bypasses a pulley (3004) at the top of the slide rail (3001), and the slider (3003) is connected to a connection ring (2004).

2. The matching system device for unplugging and sand washing without a drill floor according to claim 1, characterized in that: The clamping device (200) includes: one ends of two clamping pieces (2001) are rotatably connected through a hinge (2003), and the other ends are fixed through a fastening screw (2002), and a connection ring (2004) is provided on the hinge (2003).

3. The matching system device for unplugging and sand washing without a drilling platform according to claim 1, characterized in that: The included angle between the groove surface of the diversion groove (103) and the horizontal plane is 5° - 15°.

4. A matching system device for plug drilling and sand washing without a drill floor according to claim 1, characterized in that: The sand settling tank (104) includes: a rectangular iron pool body (1041) with internal dimensions of 4 meters in length, 3 meters in width, and 1.2 meters in height. There are 8 symmetrically arranged lifting lugs (1043) at the front and rear at the bottom of the rectangular iron pool body (1041), and a side door (1042) is provided in the middle near the bottom at the front.

5. The matching system device for unplugging plugs and flushing sand without a drill floor according to claim 2, wherein: The clamping piece (2001) is an iron tile-shaped clamping piece, and vertical alloy clamping teeth are provided on the inner arc; the anti-torque strength of the clamping device is 5 KN·m, and the rotation radius is 0.5 m.

6. The matching system device for unplugging and sand washing without a drilling platform according to claim 1, wherein: The slider (3003) is connected to the connection ring (2004) through a chain (400). When the chain (400) is in a tensioned state, the included angle with the connection ring (2004) is 90°.

7. The matching system device for unplugging and sand washing without a drilling platform according to claim 1, characterized in that: The first chute (3002) and the second chute (3006) are both T-shaped chutes, and the slider (3003) and the counterweight slider (3007) are respectively embedded in the first chute (3002) and the second chute (3006); the slider (3003) and the counterweight slider (3007) have equal weights.

8. The matching system device for unplugging and sand washing without a drill floor according to claim 1, characterized in that: The tensile strength of the slide rail (3001) is above 5 KN.

9. The matching system device for unplugging and sand washing without a drilling platform according to claim 1, characterized in that: A minor repair operation platform (600) is provided around the overflow prevention pool.

10. The construction method of the matching system device for unplugging and sand washing without a drilling rig described in any one of claims 1-9, characterized in that, Including: S1. Construction preparation: a. The minor repair equipment is relocated in place; b. Kill the well and pull out the original well tubing and rod string; c. Remove the Christmas tree, install the blowout preventer (112) and pass the pressure test; d. Install the minor repair operation platform; S2. Installation of the circulation system: a. Lower the drill and sand washing string: Connect the positive displacement motor (114), the sand washing string (111), and the swivel elbow (110) from bottom to top. After the positive displacement motor (114) detects the sand surface or plug surface, lift it by 1 meter and brake; b. Connect the inlet end of the swivel elbow (110) to the high-pressure pipeline (108) and the skid-mounted pump or pump truck (107) with a hose (109), and start the pump to conduct a pressure test. The pressure is stabilized and qualified; c. Pass a tubing through the flange connection ring (101) and the overflow prevention pool (102) according to the method of threading and replacing the wellhead, and connect and fasten with bolts; d. Place the sand settling tank (104) 4.5 meters in front of the right side of the wellhead; e. Connect the inlet end of the diversion trough (103) to the outlet of the overflow prevention pool (102), and place the outlet end of the diversion trough (103) above the sand settling tank (104); f. Connect the transfer pump (105) to the high-pressure pipeline (108) and place it beside the sand settling tank (104). The outlet end of the high-pressure pipeline (108) is connected to the inlet of the minor repair circulation tank (106); S3. Installation of the anti-reverse system: a. Fix the slide rail device (300) in front of the right side of the derrick. The first chute (3002) faces the wellhead direction. Adjust the wire rope (3005) so that both the slider (3003) and the counterweight slider (3007) are in the middle of the chute and at the same height; b. Clamp the clamping device (200) on the sand washing string (111) 1.5 meters above the minor repair operation table surface, and make one end of the connection ring (2004) face the slide rail direction. Tighten the fastening screw (2002) with a wrench; c. Adjust the height of the slider (3003) in the first chute (3002) so that the slider (3003) and the clamping device (200) are on the same horizontal plane, and connect the slider (3003) and the clamping device (200) with a chain (400); S4. Drilling and sand washing process: a. When the pump is started for circulation, the hydraulic motor at the bottom of the sand washing string (111) drives the drill bit or the milling shoe to rotate. The sand washing string (111) is kept balanced under the action of the clamping device (200) and the slide rail device (300); c. When there is drilling and sand washing footage downward, the clamping device (200) drives the slider (3003) to move downward synchronously, and drives the wire rope (3005) and the counterweight slider (3007), so that the counterweight slider (3007) moves an equal distance in the opposite direction to the slider (3003); d. During the drilling and flushing process, the well fluid returns from the wellhead and enters the overflow prevention tank (102). Under the action of gravity, it flows out of the outlet of the overflow prevention tank (102) into the diversion trough (103), and then flows into the sand settling tank (104) through the outlet of the diversion trough (103); e. When the liquid level in the sand settling tank (104) is relatively high, start the transfer pump (105) to transfer the well fluid to the workover circulation tank (106) for recycling into the well again; f. During the drilling and flushing process, it is required to promptly clean up the viscous oil blocks or other oil stains floating on the liquid surface in the sand settling tank; g. When the solid deposition in the sand settling tank (104) exceeds 30% of the tank volume, stop the drilling footage, continue to circulate the well fluid until it reaches 1.2 times the wellbore volume and then stop the pump. Remove the clamping device (200), lift the pipe feet by 20 meters, and use the transfer pump (105) to transfer all the well fluid in the sand settling tank (104) to the workover circulation tank (106), clean out all the sediments at the bottom of the tank, and simultaneously do a good job in environmental protection and hydrogen sulfide protection; h. After the sand settling tank (104) is cleaned, continue to execute according to the construction process S3 and S4; S5. Construction completion: After the drilling and flushing construction is completed, remove the following equipment: clamping device (200), slide rail device (300), diversion trough (103), overflow prevention tank (102), flange connection ring (101), sand settling tank (104).

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