Gear synchronous polymer injection device and multi-stage continuous polymer injection method thereof

Abstract

The invention discloses a gear synchronous type polymer injection device and a multistage continuous polymer injection method thereof, the gear synchronous type polymer injection device comprises a rotating mechanism, the rotating mechanism is provided with a piston rod, and the gear synchronous type polymer injection device further comprises a reversing mechanism and a transmission mechanism; the reversing mechanism is provided with a piston sleeve and an intermittent reversing mechanism; the front end of the piston rod is inserted into the piston sleeve, and the intermittent reversing mechanism is connected with a rotating part of the rotating mechanism through the transmission mechanism. The intermittent reversing mechanism switches the liquid inlet channel and the liquid outlet channel according to the movement direction of the piston rod. In the suction and discharge process, the phenomena of shape change, streaming and the like of the cross section of a runner are avoided, and the damage to a polymer molecular chain is small; and the device can operate continuously, and the pressure of the polymer outlet can be adjusted by adjusting the resistance value.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer injection, and specifically to a gear synchronous polymer injection device and its multi-stage continuous polymer injection method. Background Art

[0002] The tertiary oil recovery in oilfields has entered a new development stage, requiring fine adjustment of injection-production processes, making full use of main layers, and effectively developing thin and poor layers. To further improve the recovery factor, it is necessary to achieve layered injection, layered allocation of polymers, and maximize the retention of the injection viscosity of polymers. Therefore, developing an effective low-shear polymer distribution structure is the key to further improving the polymer flooding effect.

[0003] Existing polymer injection distribution devices mainly include piston type, coil type, cone valve type, and Venturi type; the piston type uses a positive displacement structure and can effectively reduce the shear rate when transporting large-flow injectants, but the disadvantage is that the output pressure cannot be adjusted in stages; the coil type flow controller has a compact structure and is easy to install, but the disadvantage is that the flow rate cannot be continuously adjusted and the viscosity loss is large; the disadvantage of the cone valve type flow controller is that it is bulky and difficult to achieve continuous adjustment of the flow rate; the disadvantage of the Venturi type flow controller is that the flow rate cannot be continuously adjusted.

[0004] In summary, although the existing devices can achieve the distribution of polymer injection flow rates in different formations, they cannot adjust the polymer injection pressure, and the high-shear damage to the polymer results in insufficient viscosity. Currently, the viscosity retention rate of the ground injection distribution device is 85%-90% within a pressure difference of 3 MPa, and the viscosity retention rate is lower than 80% after >5 MPa, making it difficult to meet the requirements of layered polymer injection for flow rate, pressure, and viscosity retention, thus affecting the polymer flooding displacement effect.

[0005] Publication (Announcement) No.: CN113153732A discloses a hydraulic end of a reciprocating plunger type polymer injection pump, including a liquid cylinder body, a liquid cylinder head is installed at the upper end of the liquid cylinder body, several groups of valve group mechanisms are installed in the liquid cylinder body, the valve group mechanism includes a suction valve and a discharge valve stacked vertically, a manifold type suction main pipe is connected to the lower end of the liquid cylinder body, the suction ports of the suction valves are all connected to the suction main pipe, and the suction main pipe is connected to the lower end surface of the liquid cylinder body through a connecting flange; a reciprocating plunger penetrates through one side of the liquid cylinder body, and one end of the reciprocating motion of the plunger is located in the suction valve cavity of the suction valve, and the discharge valve cavities of the discharge valves are all connected to form a discharge flow channel; the discharge flow channel has a large and small hole structure. This invention realizes effective reduction of the shear rate when transporting large-flow injectants, thereby ensuring the effectiveness of polymer flooding.

[0006] This prior art has the problem that the output pressure cannot be adjusted in stages.

[0007] Publication (Announcement) No.: CN115949383A, discloses a volumetric low-shear polymer injection device for polymer injection wells and a method for using the device, the device includes a first electric valve, a buffer device, a second electric valve, an accumulator and a third electric valve, pipeline A is the input trunk line of the polymer solution, the inlet and outlet of the first electric valve are respectively connected to pipeline A and the buffer device, the inlet and outlet of the second electric valve are respectively connected to the buffer device and the accumulator, the inlet of the third electric valve is connected to the buffer device, and the outlet is connected to the pipeline B leading to the wellhead device, the buffer device and the accumulator indirectly adjust the speed of the polymer liquid by adjusting the flow of the buffer liquid. The volumetric low-shear polymer injection device for polymer injection wells and the method for using the device can be used in the surface process of polymer injection wells in oil fields to achieve low-shear injection of polymer solutions from the trunk line to the wellhead, which is of great significance to improving the viscosity retention rate of the polymer solution and improving the oil recovery effect.

[0008] The prior art has the problem that the output pressure cannot be adjusted in stages.

[0009] Publication (Announcement) No.: CN214171488U, discloses a low shear rate plunger pump valve body and plunger pump. The plunger pump valve body and plunger pump, while ensuring the sealing effect on the medium, reduce the instantaneous rate of liquid flow when turning through the arc surface flow channel design, thereby reducing its shearing effect on the polymer. A low shear rate plunger pump valve body, the plunger pump valve body is a butterfly structure, composed of a plunger pump valve body and a plunger pump valve spherical surface; a spring mounting protrusion is provided on the plunger pump valve body, and the end of the plunger pump valve body is a spring positioning head; a spring retaining groove is also provided on the side of the spring mounting protrusion away from the end of the plunger pump valve body.

[0010] The prior art has the problem that the output pressure cannot be adjusted in stages.

[0011] In summary, the technical solutions, technical problems to be solved and beneficial effects of the above-disclosed technologies are different from the present invention. For more technical features, technical problems to be solved and beneficial effects of the present invention, the above-disclosed technical documents do not contain any technical inspiration. SUMMARY OF THE INVENTION

[0012] In view of the above-mentioned defects in the prior art, the purpose of the present invention is to provide a gear-synchronized polymer injection device and a multi-stage continuous injection method thereof, so as to make the movement smoother and the injection more efficient, so as to ensure that the pressure difference between the polymer input and discharge and the shearing of the polymer molecular chain are small during the injection.

[0013] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0014] A gear-synchronized polymer injection device comprises a rotating mechanism, wherein the rotating mechanism is provided with a piston rod, a reversing mechanism and a transmission mechanism;

[0015] The commutation mechanism is provided with a piston sleeve and an intermittent commutation mechanism;

[0016] The front end of the piston rod is inserted into the piston sleeve, and the intermittent commutation mechanism is connected to the rotating part of the rotating mechanism through a transmission mechanism; the intermittent commutation mechanism switches the liquid inlet channel and the liquid discharge channel according to the movement direction of the piston rod.

[0017] The rotating mechanism includes a box body, a crankshaft, a connecting rod, and a piston rod;

[0018] The crankshaft, the connecting rod, and the piston rod are all arranged in the box body. The crankshaft is provided with a first transmission shaft passing through the box body. The connecting rod is connected to the connecting rod shaft of the crankshaft. The piston rod is connected to the connecting rod through a cross assembly. The piston rod passes through the box body and is connected to the commutation mechanism.

[0019] The left end and the right end of the box body are installed with box body bearing end covers;

[0020] The connecting rod is provided with a front connecting rod and a rear connecting rod. The front connecting rod and the rear connecting rod are installed on the connecting rod shaft of the crankshaft through bolts. The front end of the front connecting rod is provided with a connecting handle, and a first connecting hole is arranged on the connecting handle; a convex platform is arranged at the rear end of the piston rod;

[0021] The cross assembly includes a cross head, a cross intermediate rod, a cross head pin, and a cross head nut;

[0022] The rear end of the cross intermediate rod is connected to the front end of the cross head. The left and right walls of the cross head are provided with through second connecting holes. The cross head pin penetrates into the second connecting hole and the first connecting hole;

[0023] The front end of the cross intermediate rod is provided with a concave platform matching the convex platform of the piston rod. The convex platform of the piston rod is inserted into the concave platform. The cross head nut locks the convex platform of the piston rod at the front end of the cross intermediate rod. A circular ring with a diameter smaller than that of the cross head nut is also arranged between the cross head nut and the convex platform of the piston rod.

[0024] The commutation mechanism further includes a connecting seat and a plunger seat. The intermittent commutation mechanism includes an intermittent driving mechanism and a liquid flow channel switching mechanism;

[0025] The front end of the piston rod is provided with a first piston. The first piston is inserted into the connecting seat. The piston sleeve is arranged in the connecting seat. The first piston slides in the piston sleeve;

[0026] The intermittent driving mechanism is arranged at the upper end of the connecting seat. The intermittent driving mechanism is connected to the first transmission shaft through a transmission mechanism. The liquid flow channel switching mechanism is arranged at the front end of the connecting seat. The intermittent driving mechanism and the liquid flow channel switching mechanism are connected through a transmission part.

[0027] The intermittent drive mechanism includes a camshaft;

[0028] At the upper end of the connecting seat, there are a left bearing seat and a right bearing seat. The camshaft passes through the left bearing seat and the right bearing seat. The camshaft is provided with a second transmission shaft passing through the left bearing seat or the right bearing seat, and the second transmission shaft is on the same side of the device as the first transmission shaft;

[0029] The camshaft is provided with a cam. The cam is provided with a large-diameter circle and a small-diameter circle, and there is a smooth transition between the large-diameter circle and the small-diameter circle. The cam drives the liquid flow channel switching mechanism through a transmission part.

[0030] The liquid flow channel switching mechanism includes a plunger seat and an inlet / outlet plunger;

[0031] The front end of the piston sleeve is connected to the rear end of the plunger seat. The inner wall of the plunger seat is provided with a piston port, which connects the inside of the plunger seat with the piston sleeve;

[0032] The plunger seat is provided with a plunger seat inlet and a plunger seat outlet;

[0033] The inlet / outlet plunger is arranged in the plunger seat. There is an inlet / outlet plunger sleeve between the inlet / outlet plunger and the plunger seat. The wall of the inlet / outlet plunger sleeve is provided with an inlet connection hole, a discharge connection hole, and a piston connection hole; the inlet connection hole communicates with the plunger seat inlet, the discharge connection hole communicates with the plunger seat outlet, and the piston connection hole communicates with the piston port.

[0034] An adjusting rod is arranged at the upper end of the inlet / outlet plunger. The adjusting rod passes through the plunger seat, and the transmission part is a fork;

[0035] A fork seat is arranged at the upper end of the plunger seat. The fork is rotatably arranged on the fork seat. The front end of the fork is movably connected to the upper end of the adjusting rod, and the rear end is in contact with the cam;

[0036] A return spring retaining piece is arranged on the adjusting rod. A spring is arranged below the return spring retaining piece. The spring presses the return spring retaining piece upward and presses the plunger seat downward, so that the inlet / outlet plunger can be reset.

[0037] The front end of the fork is in contact with the upper end of the adjusting rod. Rollers are arranged at both the front end and the rear end of the fork; the rollers are connected to the fork by pins.

[0038] The connecting seat is connected to the box body. An upper gland is arranged at the upper end of the inlet / outlet plunger sleeve, and a lower gland is arranged at the lower end of the inlet / outlet plunger sleeve. The lower gland is provided with a flat pressing hole;

[0039] A seal cover is arranged at the right end of the piston sleeve. The left bearing seat is provided with a left bearing end cover, and the right bearing seat is provided with a right bearing end cover.

[0040] The inlet and outlet plunger is provided with an upper sealing ring and a lower sealing ring;

[0041] When the lower sealing ring seals the liquid discharge connection hole, the upper sealing ring is above the liquid inlet connection hole, the piston connection hole is above the lower sealing ring, and the piston port is communicated with the liquid inlet of the plunger seat through the piston connection hole, the cavity between the upper and lower sealing rings, and the liquid inlet connection hole;

[0042] When the upper sealing ring seals the liquid inlet connection hole, the lower sealing ring is below the liquid discharge connection hole, the piston connection hole is below the upper sealing ring, and the piston port is communicated with the liquid discharge port of the plunger seat through the piston connection hole, the cavity between the upper and lower sealing rings, and the liquid discharge connection hole;

[0043] Both the upper sealing ring and the lower sealing ring include a first sealing seat and a second sealing seat. Third O-rings are arranged on both the first sealing seat and the second sealing seat. The distance between the first sealing seat and the second sealing seat is greater than the aperture diameters of the liquid inlet connection hole and the liquid discharge connection hole.

[0044] The connection between the connection seat and the box body, the connection between the camshaft seat and the connection seat, the connection between the small bearing seat and the connection seat, and the connection between the large bearing seat and the connection seat are all connected by bolts;

[0045] The connection between the shift fork and the shift fork seat is all connected by pins;

[0046] The cam is fixed on the camshaft by a key, and a camshaft sleeve or a short camshaft sleeve is sleeved on the camshaft to position the cam;

[0047] A first O-ring is sleeved on the inlet and outlet plunger sleeve, a second O-ring is sleeved on the outer wall of the first piston, and a fourth O-ring is sleeved on the connection part between the front end of the piston sleeve and the plunger seat.

[0048] The transmission mechanism includes a camshaft bevel gear, a gear shaft seat, a gear shaft, and a crankshaft bevel gear;

[0049] The camshaft bevel gear is arranged on the second transmission shaft. The gear shaft seat is connected to the box body and is arranged between the first transmission shaft and the second transmission shaft. A front intermediate bevel gear is arranged at the front end of the gear shaft, and a rear intermediate bevel gear is arranged at the rear end of the gear shaft;

[0050] The gear shaft passes through the gear shaft seat. The front intermediate bevel gear meshes with the camshaft bevel gear, and the rear intermediate bevel gear meshes with the crankshaft bevel gear.

[0051] The gear shaft seat is provided with a gear shaft end cover;

[0052] The camshaft bevel gear is connected to the camshaft by a key, and the camshaft bevel gear is limited by a second set screw to the shaft shoulder. The front and rear intermediate bevel gears are connected to the gear shaft by a key, and the front and rear intermediate bevel gears are limited by a first set screw to the shaft shoulder. The crankshaft bevel gear is connected to the crankshaft by a key, and the crankshaft bevel gear is limited by the shaft shoulder.

[0053] In an embodiment of the present invention, at least three connecting rod shafts of the crankshaft are circumferentially and uniformly arranged, and the numbers of the connecting rod, the piston rod, the fork, the inlet and outlet liquid plunger, the cam, the piston sleeve, and the inlet and outlet liquid plunger sleeve are the same as the number of the connecting rod shafts of the crankshaft, all being at least three.

[0054] In an embodiment of the present invention, the first transmission shaft or the second transmission shaft is connected to a damping adjustment mechanism. The damping adjustment mechanism includes a generator, the input shaft of the generator is connected to the first transmission shaft, and the generator is connected with a rheostat.

[0055] In an embodiment of the present invention, the first transmission shaft or the second transmission shaft is connected to the output shaft of a driving device, and the driving device is an internal combustion engine or an electric motor.

[0056] A multi-stage continuous polymer injection method for a gear synchronization type polymer injection device includes the following steps:

[0057] S1. Connect the first transmission shaft or the second transmission shaft to the damping adjustment mechanism, connect the polymer inlet pipe to the liquid inlet of the plunger seat, and connect the polymer output pipe to the liquid outlet of the plunger seat; according to the construction requirements, adjust the resistance generated by the generator through the rheostat in the damping adjustment mechanism.

[0058] S2. Press in the polymer. The intermittent commutation mechanism conducts the liquid inlet of the plunger seat to the piston sleeve, that is, the contact between the cam and the fork is a small diameter contact. The lower sealing ring seals the liquid discharge connection hole, the upper sealing ring is above the liquid inlet connection hole, the piston connection hole is above the lower sealing ring, and the movement path of the polymer is through the liquid inlet of the plunger seat, the liquid inlet connection hole, the cavity between the upper and lower sealing rings, the piston connection hole, and the piston port, enters the piston sleeve, and pushes the first piston to move backward, causing the crankshaft to rotate.

[0059] The first transmission shaft rotates. The first transmission shaft drives the second transmission shaft through the gear shaft, causing the camshaft to rotate, causing the intermittent commutation mechanism to switch, disconnecting the liquid inlet of the plunger seat from the piston sleeve, and conducting the liquid outlet of the plunger seat to the piston sleeve; that is, the contact between the cam and the fork changes from a small diameter contact to a large diameter contact, and the inlet and outlet liquid plunger moves downward, causing the upper sealing ring to seal the liquid inlet connection hole, the lower sealing ring is below the liquid discharge connection hole, and the piston connection hole is below the upper sealing ring.

[0060] S3. The first transmission shaft continues to rotate, and the crankshaft continues to rotate, pushing the first piston forward to cause the polymer in the piston sleeve to enter the polymer output pipe, that is, through the piston port, piston connection hole, cavity between the upper and lower sealing rings, drain connection hole, and drain port of the plunger seat to enter the polymer output pipe and be injected into the formation;

[0061] The intermittent commutation mechanism switches to conduct the liquid inlet of the plunger seat with the piston sleeve and disconnect the drain port of the plunger seat from the piston sleeve, that is, the contact between the cam and the fork changes from large-diameter contact to small-diameter contact, and the cycle operation starts.

[0062] A continuous polymer injection method for a gear synchronization type polymer injection device includes the following steps:

[0063] S1. Connect the first transmission shaft or the second transmission shaft to the output shaft of the driving device, connect the polymer inlet pipe to the liquid inlet of the plunger seat, and connect the polymer output pipe to the drain port of the plunger seat. The driving device is an internal combustion engine or an electric motor;

[0064] S2. Start the driving device. The first transmission shaft and the second transmission shaft start to rotate synchronously under the action of the rotating mechanism. The intermittent commutation mechanism conducts the liquid inlet of the plunger seat with the piston sleeve, and the first piston moves backward to generate negative pressure. The contact between the cam and the fork is small-diameter contact. The lower sealing ring seals the drain connection hole. The upper sealing ring is above the liquid inlet connection hole, and the piston connection hole is above the lower sealing ring. The polymer enters the piston sleeve through the liquid inlet of the plunger seat, liquid inlet connection hole, cavity between the upper and lower sealing rings, piston connection hole, and piston port;

[0065] The second transmission shaft continues to rotate, and the camshaft rotates to cause the intermittent commutation mechanism to switch, disconnect the liquid inlet of the plunger seat from the piston sleeve, and conduct the drain port of the plunger seat with the piston sleeve, that is, the contact between the cam and the fork changes from small-diameter contact to large-diameter contact. The inlet and drain plunger moves downward to cause the upper sealing ring to seal the liquid inlet connection hole. The lower sealing ring is below the drain connection hole, and the piston connection hole is below the upper sealing ring;

[0066] S3. The first transmission shaft continues to rotate, and the crankshaft continues to rotate, pushing the first piston forward to cause the polymer in the piston sleeve to enter the polymer output pipe. The polymer enters the polymer output pipe through the piston port, piston connection hole, cavity between the upper and lower sealing rings, drain connection hole, and drain port of the plunger seat and is injected into the formation. The intermittent commutation mechanism switches, that is, the contact between the cam and the fork changes from large-diameter contact to small-diameter contact, conducts the liquid inlet of the plunger seat with the piston sleeve, and disconnects the drain port of the plunger seat from the piston sleeve to start the cycle operation.

[0067] The present invention has the following beneficial effects compared with the prior art:

[0068] The present invention adopts a positive displacement type for sucking and discharging polymers. During the positive displacement sucking and discharging process, there are no phenomena such as changes in the cross-sectional shape of the flow channel and flow around, which causes less damage to the polymer molecular chains.

[0069] The device realizes the sucking and discharging of polymers through the reciprocating motion of three pistons, reduces the damage to the polymer molecular chains during the polymer injection process, ensures the viscosity of the polymer, and achieves low shear.

[0070] The bevel gear cooperation between the camshaft and the crankshaft can ensure the synchronous operation between the camshaft and the crankshaft, and further realize the switching of the polymer liquid inlet and liquid discharge flow channels.

[0071] Multiple sets of actuating components are provided to ensure the continuous operation of the entire device.

[0072] The damping adjustment mechanism composed of a generator and a rheostat can adjust the polymer outlet pressure by adjusting the resistance value. Description of the Drawings

[0073] Figure 1 is a schematic structural diagram of a gear synchronous polymer injection device of the present invention;

[0074] Figure 2 is a schematic internal structure diagram of the commutation mechanism and the rotation mechanism of a gear synchronous polymer injection device of the present invention;

[0075] Figure 3 is a sectional view of the commutation mechanism and the rotation mechanism of a gear synchronous polymer injection device of the present invention;

[0076] Figure 4 is a schematic diagram of the liquid inlet state of a gear synchronous polymer injection device of the present invention;

[0077] Figure 5 is a schematic diagram of the liquid discharge state of a gear synchronous polymer injection device of the present invention;

[0078] In the figure: 1. Roller; 2. Fork; 3. Fork seat; 4. Left bearing seat; 5. Left bearing seat end cover; 6. Cam; 7. Camshaft sleeve; 8. Short camshaft sleeve; 9. Right bearing seat end cover; 10. Right bearing seat; 11. Small cover plate; 12. Box body; 13. Large cover plate; 14. Box body bearing end cover; 15. Crankshaft bevel gear; 16. Rear intermediate bevel gear; 16-1. Set bolt; 17. Gear shaft seat; 18. Gear shaft end cover; 19. Gear shaft; 20. Camshaft bevel gear; 20-1. Set bolt; 21. Connecting seat; 22. Return spring retaining plate; 23. Spring; 24. Plunger seat; 24-1. Liquid inlet of plunger seat; 24-2. Liquid outlet of plunger seat; 24-3. Piston port; 25. Lower pressing cover; 26. Upper pressing cover; 27. Liquid inlet and outlet plunger sleeve; 27-1. First O-ring; 27-2. Liquid inlet connection hole; 27-3. Liquid outlet connection hole; 27-4. Piston connection hole; 28. Piston rod; 29. Crosshead nut; 30. Crosshead intermediate rod; 31. Crosshead; 32. Front end of connecting rod; 33. Rear end of connecting rod; 34. Crankshaft; 35. Crosshead pin; 36. Ring; 37. Camshaft; 38. Sealing cover; 39. First piston; 39-1. Second O-ring; 40. Liquid inlet and outlet plunger; 40-1. Third O-ring; 41. Piston sleeve; 41-1. Fourth O-ring; 42. Generator; 43. Rheostat. Detailed implementation mode

[0079] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0080] Embodiment 1:

[0081] Please refer to Figures 1 to 3 , a gear synchronous polymer injection device provided by the present invention and its multi-stage continuous polymer injection method include a commutation mechanism, a rotation mechanism, a transmission mechanism, and a damping adjustment mechanism.

[0082] The rotation mechanism includes a box body 12, a crankshaft 34, a connecting rod, and a piston rod 28. The crankshaft 34, the connecting rod, and the piston rod 28 are all arranged in the box body 12. The crankshaft 34 is provided with a first transmission shaft passing through the box body 12. The connecting rod is connected to the connecting rod shaft of the crankshaft 34. The piston rod 28 is connected to the connecting rod through a cross assembly. The piston rod 28 passes through the box body and is connected to the commutation mechanism;

[0083] At the left and right ends of the box body 12, box body bearing end covers 14 are installed to fix the crankshaft 34; the connecting rod is provided with a front connecting rod 32 and a rear connecting rod 33. The front connecting rod 32 and the rear connecting rod 33 are installed on the connecting rod shaft of the crankshaft 34 through bolts. A connecting handle is provided at the front end of the front connecting rod 32, and a first connecting hole is provided on the connecting handle; a first piston 39 is provided at the front end of the piston rod 28, and a boss is provided at the rear end. The first piston 39 is inserted into the connecting seat 21;

[0084] The cross assembly includes a crosshead 31, a cross intermediate rod 30, a crosshead pin 35, and a crosshead nut 29. The rear end of the cross intermediate rod 30 is connected to the front end of the crosshead 31. Through holes are provided in the left and right walls of the crosshead 31 as second connecting holes. The crosshead pin 35 passes through the second connecting hole and the first connecting hole to connect the crosshead 31 and the front connecting rod 32. A concave platform matching the boss of the piston rod 28 is provided at the front end of the cross intermediate rod 30. The boss of the piston rod 28 is inserted into the concave platform. The crosshead nut 29 locks the boss of the piston rod 28 at the front end of the cross intermediate rod 30. A ring 36 with a diameter smaller than that of the crosshead nut 29 is also provided between the crosshead nut 29 and the boss of the piston rod 28 to enhance the locking effect.

[0085] The commutation mechanism includes a connecting seat 21, a plunger seat 24, a camshaft 37, a fork 2, and an inlet and outlet liquid plunger 40; the connecting seat 21 is connected to the box body 12. A left bearing seat 4 and a right bearing seat 10 are provided at the upper end of the connecting seat 21. A piston sleeve 41 is provided inside the connecting seat 21. The first piston 39 slides in the piston sleeve 41. The camshaft 37 passes through the left bearing seat 4 and the right bearing seat 10. The camshaft 37 is provided with a second transmission shaft passing through the left bearing seat 4 or the right bearing seat 10. The second transmission shaft and the first transmission shaft are on the same side of the device. A cam 6 is provided on the camshaft 37; the front end of the piston sleeve 41 is connected to the rear end of the plunger seat 24. A piston port 24-3 is provided on the inner wall of the plunger seat 24 to connect the inside of the plunger seat 24 and the piston sleeve 41; a left bearing end cover 5 is provided on the left bearing seat 4, and a right bearing end cover 9 is provided on the right bearing seat 10.

[0086] A plunger seat inlet 24-1 and a plunger seat outlet 24-2 are provided at the left or right end of the plunger seat. A fork seat 3 is provided on the plunger seat 24. The inlet and outlet liquid plunger 40 is provided in the plunger seat 24. An adjusting rod is provided at the upper end of the inlet and outlet liquid plunger 40. The adjusting rod passes through the plunger seat 24. The fork 2 is rotatably provided on the fork seat 3. The front end of the fork 2 is movably connected to the upper end of the adjusting rod, and the rear end is in contact with the cam 6. The cam 6 is provided with a large-diameter circle and a small-diameter circle, and the large-diameter circle and the small-diameter circle are provided with a smooth transition.

[0087] A cover 38 is provided at the right end of the piston sleeve 41. An inlet and outlet liquid plunger sleeve 27 is provided between the inlet and outlet liquid plunger 40 and the plunger seat 24. Liquid inlet connection holes 27-2, liquid discharge connection holes 27-3, and piston connection holes 27-4 are provided on the wall of the inlet and outlet liquid plunger sleeve 27. The liquid inlet connection holes 27-2 communicate with the liquid inlet of the plunger seat 24-1. The liquid discharge connection holes 27-3 communicate with the liquid discharge port of the plunger seat 24-2. The piston connection holes 27-4 communicate with the piston port 24-3.

[0088] The inlet and outlet liquid plunger 40 is provided with an upper sealing ring and a lower sealing ring. As Figure 4 shown, the lower sealing ring seals the liquid discharge connection holes 27-3. The upper sealing ring is above the liquid inlet connection holes 27-2. The piston connection holes 27-4 are above the lower sealing ring. The piston port 24-3 communicates with the liquid inlet of the plunger seat 24-1 through the piston connection holes 27-4, the cavity between the upper and lower sealing rings, and the liquid inlet connection holes 27-2. As Figure 5 shown, the upper sealing ring seals the liquid inlet connection holes 27-2. The lower sealing ring is below the liquid discharge connection holes 27-3. The piston connection holes 27-4 are below the upper sealing ring. The piston port 24-3 communicates with the liquid discharge port of the plunger seat 24-2 through the piston connection holes 27-4, the cavity between the upper and lower sealing rings, and the liquid discharge connection holes 27-3.

[0089] Both the upper sealing ring and the lower sealing ring include a first sealing seat and a second sealing seat. Third O-ring 40-1 is provided on both the first sealing seat and the second sealing seat. The distance between the first sealing seat and the second sealing seat is greater than the diameters of the liquid inlet connection holes 27-2 and the liquid discharge connection holes 27-3.

[0090] An upper pressing cover 26 is provided at the upper end of the inlet and outlet liquid plunger sleeve 27. A lower pressing cover 25 is provided at the lower end of the inlet and outlet liquid plunger sleeve 27. The lower pressing cover 25 is provided with a flat pressing hole to prevent the inlet and outlet liquid plunger 40 from being stuck. A return spring retaining piece 22 is provided on the adjusting rod. A spring 23 is provided below the return spring retaining piece 22. The spring 23 presses the return spring retaining piece 22 upward and presses the upper pressing cover 26 downward.

[0091] The front end of the shift fork 2 contacts the upper end of the adjusting rod. Rollers 1 are provided at both the front end and the rear end of the shift fork 2 to change the contact into a sliding contact and reduce the frictional loss.

[0092] A small cover plate 11 is provided above the piston rod 28 on the box body 12, and a large cover plate 13 is provided above the crankshaft 34 to facilitate maintenance.

[0093] The transmission mechanism includes a camshaft bevel gear 20, a gear shaft seat 17, a gear shaft 19, and a crankshaft bevel gear 15; the camshaft bevel gear 20 is arranged on the second transmission shaft, the gear shaft seat 17 is connected to the box body 12 and is arranged between the first transmission shaft and the second transmission shaft, a front intermediate bevel gear is arranged at the front end of the gear shaft 19, and a rear intermediate bevel gear 16 is arranged at the rear end. The gear shaft 19 passes through the gear shaft seat 17, the front intermediate bevel gear meshes with the camshaft bevel gear 20, the rear intermediate bevel gear 16 meshes with the crankshaft bevel gear 15, and a gear shaft end cover 18 is installed on the gear shaft seat 17.

[0094] The damping adjustment mechanism includes a generator 42, the input shaft of the generator 42 is connected to the first transmission shaft or the second transmission shaft, and the generator 42 is connected with a rheostat 43.

[0095] This embodiment is used as a multi-stage hydraulic injection device:

[0096] S1. Connect the first transmission shaft or the second transmission shaft to the damping adjustment mechanism, connect the polymer inlet pipe to the liquid inlet 24-1 of the plunger seat, and connect the polymer output pipe to the liquid discharge port 24-2 of the plunger seat; according to the construction requirements, adjust the resistance generated by the generator 42 through the rheostat 43.

[0097] S2. Press in the polymer. The contact between the cam 6 and the fork 2 is a small-diameter contact. The lower sealing ring seals the liquid discharge connection hole 27-3, the upper sealing ring is above the liquid inlet connection hole 27-2, the piston connection hole 27-4 is above the lower sealing ring. The polymer passes through the liquid inlet 24-1 of the plunger seat, the liquid inlet connection hole 27-2, the cavity between the upper and lower sealing rings, the piston connection hole 27-4, and the piston port 24-3, enters the piston sleeve 41, pushes the first piston 39 to move backward, drives the crankshaft 34 to rotate, the crankshaft 34 drives the gear shaft 19 to rotate, the gear shaft 19 drives the camshaft 37 to rotate, so that the contact between the cam 6 and the fork 2 changes from small-diameter contact to large-diameter contact, and the inlet and outlet liquid plunger 40 moves downward, so that the upper sealing ring seals the liquid inlet connection hole 27-2, the lower sealing ring is below the liquid discharge connection hole 27-3, and the piston connection hole 27-4 is below the upper sealing ring.

[0098] S3. The crankshaft 34 continues to rotate, pushes the first piston 39 to move forward, so that the polymer in the piston sleeve 41 passes through the piston port 24-3, the piston connection hole 27-4, the cavity between the upper and lower sealing rings, the liquid discharge connection hole 27-3, and the liquid discharge port 24-2 of the plunger seat and enters the polymer output pipe, and is injected into the formation. The contact between the cam 6 and the fork 2 changes from large-diameter contact to small-diameter contact, and starts to run in a cycle.

[0099] Among them, adjusting the resistance value of the rheostat 43 can achieve different energy consumption, and further adjust the pressure when the polymer is discharged, realizing the function of pressure regulation. This usage method is hydraulic drive.

[0100] Example 2:

[0101] On the basis of Example 1, the present invention has the ability of continuous polymer injection, and the connection mode of parts is further defined. At least three connecting rod journals of the crankshaft 34 are circumferentially and uniformly arranged. The number of the connecting rods, the piston rods 28, the shift forks 2, the inlet and outlet liquid plungers 40, the cams 6, the piston sleeves 41, and the inlet and outlet liquid plunger sleeves 27 is the same as that of the connecting rod journals of the crankshaft 34, and is at least three.

[0102] When in use in this embodiment, at least three groups of connecting rods, piston rods 28, shift forks 2, inlet and outlet liquid plungers 40, and cams 6 move alternately, greatly improving the continuity of polymer injection.

[0103] The connection mode of each part of the present invention is further defined. The connection between the connection seat 21 and the box body 12, the connection between the camshaft seat 24 and the connection seat 21, the connection between the small bearing seat 4 and the connection seat 21, and the connection between the large bearing seat 10 and the connection seat 21 are all connected by bolts; the connection between the roller 1 and the shift fork 2, and the connection between the shift fork 2 and the shift fork seat 3 are all pin connections; the cam 6 is fixed on the camshaft 37 by a key, and a camshaft sleeve 7 or a short camshaft sleeve 8 is sleeved on the camshaft 37 to position the cam 6.

[0104] A first O-ring 27-1 is sleeved on the inlet and outlet liquid plunger sleeve 27, a second O-ring 39-1 is sleeved on the outer wall of the first piston, and a fourth O-ring 41-1 is sleeved on the connection part between the front end of the piston sleeve 41 and the plunger seat 24 to enhance the sealing performance of the device.

[0105] The camshaft bevel gear 20 is connected to the camshaft 37 by a key, and the camshaft bevel gear 20 is limited by a second set screw 20-1 to the shaft shoulder. The front and rear intermediate bevel gears 16 are connected to the gear shaft 19 by a key, and the intermediate bevel gear 16 is limited by a first set screw 16-1 to the shaft shoulder. The crankshaft bevel gear 15 is connected to the crankshaft 34 by a key, and the crankshaft bevel gear 15 is limited by the shaft shoulder.

[0106] Example 3:

[0107] On the basis of Example 2, the device is used as an ordinary low-shear injection device. The first transmission shaft or the second transmission shaft is connected to the output shaft of the driving device, and the driving device is an internal combustion engine or an electric motor.

[0108] Using this embodiment as a low-shear continuous injection device:

[0109] S1. Connect the first transmission shaft or the second transmission shaft to the output shaft of the driving device, connect the polymer inlet pipe to the liquid inlet 24-1 of the plunger seat, and connect the polymer output pipe to the liquid outlet 24-2 of the plunger seat;

[0110] S2. Start the driving device. The gear shaft 19 causes the crankshaft 34 and the camshaft 37 to rotate synchronously. The crankshaft 34 drives the first piston 39 to move backward, generating negative pressure. The cam 6 and the fork 2 are in contact with a small diameter. The lower sealing ring seals the liquid discharge connection hole 27-3. The upper sealing ring is above the liquid inlet connection hole 27-2, and the piston connection hole 27-4 is above the lower sealing ring. The polymer enters the piston sleeve 41 through the liquid inlet of the plunger seat 24-1, the liquid inlet connection hole 27-2, the cavity between the upper and lower sealing rings, the piston connection hole 27-4, and the piston port 24-3.

[0111] Meanwhile, the camshaft 37 rotates, causing the contact between the cam 6 and the fork 2 to change from small diameter contact to large diameter contact. The liquid inlet and outlet plunger 40 moves downward, causing the upper sealing ring to seal the liquid inlet connection hole 27-2. The lower sealing ring is below the liquid discharge connection hole 27-3, and the piston connection hole 27-4 is below the upper sealing ring.

[0112] S3. The crankshaft 34 continues to rotate, causing the first piston 39 to move forward. The polymer in the piston sleeve 41 enters the polymer output pipe through the piston port 24-3, the piston connection hole 27-4, the cavity between the upper and lower sealing rings, the liquid discharge connection hole 27-3, and the liquid discharge port of the plunger seat 24-2, and is injected into the formation. The contact between the cam 6 and the fork 2 changes from large diameter contact to small diameter contact, and the cycle starts again.

[0113] This usage method is driven by mechanical force.

[0114] In this application, any components that are not elaborated on themselves and the connection methods of the various components in this application belong to the well-known technologies in this technical field and can be directly applied without further elaboration.

[0115] In the present invention, the term "plurality" refers to two or more, unless otherwise clearly defined. Terms such as "installation", "connection", "linkage", "fixation" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; "linkage" can be a direct linkage or an indirect linkage through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0116] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "front", "rear", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or unit referred to must have a specific direction, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of the present invention.

[0117] In the description of this specification, the descriptions of the terms "one embodiment", "some embodiments", "specific embodiments", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or instance. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0118] The foregoing are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A gear-synchronized polymer injection device, comprising a rotating mechanism, wherein the rotating mechanism is provided with a piston rod, characterized in that: It also includes a reversing mechanism and a transmission mechanism; The reversing mechanism is provided with a piston sleeve and an intermittent reversing mechanism; The front end of the piston rod is inserted into the piston sleeve, and the intermittent reversing mechanism is connected to the rotating part of the rotating mechanism through a transmission mechanism; the intermittent reversing mechanism switches the liquid inlet channel and the liquid discharge channel according to the movement direction of the piston rod.

2. A gear-synchronized polymer injection device according to claim 1, characterized in that: The rotating mechanism comprises a housing, a crankshaft, a connecting rod and a piston rod; The crankshaft, connecting rod and piston rod are all arranged in a box body. The crankshaft is provided with a first transmission shaft passing through the box body. The connecting rod is connected to the connecting rod shaft of the crankshaft. The piston rod is connected to the connecting rod through a cross assembly. The piston rod passes through the box body and is connected to the reversing mechanism.

3. A gear-synchronized polymer injection device according to claim 2, characterized in that: The box body bearing end covers are installed at the left and right ends of the box body; The connecting rod is provided with a front connecting rod and a rear connecting rod, and the front connecting rod and the rear connecting rod are installed on the connecting rod shaft of the crankshaft through bolts. The front end of the front connecting rod is provided with a connecting handle, and the connecting handle is provided with a first connecting hole; the rear end of the piston rod is provided with a boss; The cross assembly includes a cross head, a cross intermediate rod, a cross head pin, and a cross head nut; The rear end of the cross rod is connected to the front end of the cross head, and the left and right walls of the cross head are provided with second connecting holes, and the cross head pin is inserted into the second connecting hole and the first connecting hole; The front end of the cross rod is provided with a recessed platform matching the piston rod boss, the piston rod boss is inserted into the recessed platform, the cross head nut locks the piston rod boss at the front end of the cross rod, and a circular ring with a smaller aperture than the cross head nut is also provided between the cross head nut and the piston rod boss.

4. The gear-synchronized polymer injection device according to claim 2, characterized in that: The reversing mechanism further comprises a connecting seat and a plunger seat, and the intermittent reversing mechanism comprises an intermittent driving mechanism and a liquid flow channel switching mechanism; A first piston is arranged at the front end of the piston rod, the first piston is inserted into a connecting seat, the piston sleeve is arranged in the connecting seat, and the first piston slides in the piston sleeve; The intermittent drive mechanism is arranged at the upper end of the connecting seat, and the intermittent drive mechanism is connected to the first transmission shaft through a transmission mechanism. The liquid flow channel switching mechanism is arranged at the front end of the connecting seat, and the intermittent drive mechanism and the liquid flow channel switching mechanism are connected through a transmission member.

5. The gear-synchronized polymer injection device according to claim 4, characterized in that: The intermittent drive mechanism includes a camshaft; The upper end of the connecting seat is provided with a left bearing seat and a right bearing seat, the camshaft passes through the left bearing seat and the right bearing seat, the camshaft is provided with a second transmission shaft passing through the left bearing seat or the right bearing seat, and the second transmission shaft and the first transmission shaft are on the same side of the device; The camshaft is provided with a cam, the cam is provided with a large diameter circle and a small diameter circle, a smooth transition is provided between the large diameter circle and the small diameter circle, and the cam drives the liquid flow channel switching mechanism through a transmission member.

6. The gear-synchronized polymer injection device according to claim 5, characterized in that: The liquid flow channel switching mechanism includes a plunger seat and a liquid inlet and outlet plunger; The front end of the piston sleeve is connected to the rear end of the plunger seat, and the inner wall of the plunger seat is provided with a piston port to connect the inside of the plunger seat with the piston sleeve; The plunger seat is provided with a plunger seat liquid inlet and a plunger seat liquid discharge port; The liquid inlet and discharge plunger is arranged in the plunger seat, and a liquid inlet and discharge plunger sleeve is arranged between the liquid inlet and discharge plunger and the plunger seat, and a liquid inlet connecting hole, a liquid discharge connecting hole, and a piston connecting hole are arranged on the wall of the liquid inlet and discharge plunger sleeve; the liquid inlet connecting hole is connected with the liquid inlet port of the plunger seat, the liquid discharge connecting hole is connected with the liquid discharge port of the plunger seat, and the piston connecting hole is connected with the piston port.

7. The gear-synchronized polymer injection device according to claim 6, characterized in that: An adjusting rod is arranged at the upper end of the liquid inlet and outlet plunger, the adjusting rod passes through the plunger seat, and the transmission member is a pulling fork; The upper end of the plunger seat is provided with a fork seat, the fork is rotatably arranged on the fork seat, the front end of the fork is movably connected to the upper end of the adjusting rod, and the rear end is in contact with the cam; The adjusting rod is provided with a return spring baffle, and a spring is provided below the return spring baffle. The spring pushes the return spring baffle upward and pushes the plunger seat downward, so that the inlet and outlet plunger can be reset.

8. The gear-synchronized polymer injection device according to claim 7, characterized in that: The front end of the shift fork contacts the upper end of the adjusting rod, and rollers are arranged at the front end and the rear end of the shift fork; the rollers are connected to the shift fork by a pin.

9. The gear-synchronized polymer injection device according to claim 7, characterized in that: The connecting seat is connected to the box body, an upper pressure cover is provided at the upper end of the inlet and outlet plunger sleeve, and a lower pressure cover is provided at the lower end of the inlet and outlet plunger sleeve, and the lower pressure cover is provided with a flat pressure hole; The right end of the piston sleeve is provided with a sealing cover, the left bearing seat is provided with a left bearing end cover, and the right bearing seat is provided with a right bearing end cover.

10. The gear-synchronized polymer injection device according to claim 6, characterized in that: The liquid inlet and outlet plunger is provided with an upper sealing ring and a lower sealing ring; When the lower sealing ring seals the discharge connection hole, the upper sealing ring is above the inlet connection hole, the piston connection hole is above the lower sealing ring, and the piston port is connected to the plunger seat inlet through the piston connection hole, the cavity between the upper and lower sealing rings, and the inlet connection hole; When the upper sealing ring seals the liquid inlet connection hole, the lower sealing ring is below the liquid discharge connection hole, the piston connection hole is below the upper sealing ring, and the piston port is connected to the liquid discharge port of the plunger seat through the piston connection hole, the cavity between the upper and lower sealing rings, and the liquid discharge connection hole; The upper sealing ring or the lower sealing ring includes a first sealing seat and a second sealing seat, and a third O-ring is arranged on the first sealing seat and the second sealing seat. The distance between the first sealing seat and the second sealing seat is greater than the aperture of the liquid inlet connecting hole and the aperture of the liquid discharge connecting hole.

11. The gear-synchronized polymer injection device according to claim 9, characterized in that: The connection between the connecting seat and the housing, the connection between the camshaft seat and the connecting seat, the connection between the small bearing seat and the connecting seat, and the connection between the large bearing seat and the connecting seat are all connected by bolts; The connection between the fork and the fork seat is pin connection; The cam is fixed on the camshaft by a key, and the camshaft is sleeved with a camshaft sleeve or a short camshaft sleeve to position the cam; The inlet and outlet plunger sleeve is covered with a first O-ring, the outer wall of the first piston is covered with a second O-ring, and the connecting part between the front end of the piston sleeve and the plunger seat is covered with a fourth O-ring.

12. The gear-synchronized polymer injection device according to claim 5, characterized in that: The transmission mechanism includes a camshaft bevel gear, a gear shaft seat, a gear shaft, and a crankshaft bevel gear; The camshaft bevel gear is arranged on the second transmission shaft, the gear shaft seat is connected to the box body and is arranged between the first transmission shaft and the second transmission shaft, the front end of the gear shaft is provided with a front intermediate bevel gear, and the rear end is provided with a rear intermediate bevel gear; The gear shaft passes through the gear shaft seat, the front intermediate bevel gear is meshed with the camshaft bevel gear, and the rear intermediate bevel gear is meshed with the crankshaft bevel gear.

13. The gear-synchronized polymer injection device according to claim 12, characterized in that: The gear shaft seat is provided with a gear shaft end cover; The camshaft bevel gear is connected to the camshaft via a key, and the camshaft bevel gear is limited by a second fixing bolt and a shaft shoulder. The front and rear intermediate bevel gears are connected to the gear shaft via a key, and the front and rear intermediate bevel gears are limited by a first fixing bolt and a shaft shoulder. The crankshaft bevel gear is connected to the crankshaft via a key, and the crankshaft bevel gear is limited by a shaft shoulder.

14. The gear-synchronized polymer injection device according to claim 7, characterized in that: At least three connecting rod shafts of the crankshaft are evenly arranged in the circumferential direction, and the number of the connecting rod, piston rod, shift fork, inlet and outlet plunger, cam, piston sleeve, inlet and outlet plunger sleeve is consistent with the number of the connecting rod shaft of the crankshaft, which is at least three.

15. A gear-synchronized polymer injection device according to any one of claims 2 to 14, characterized in that: The first transmission shaft or the second transmission shaft is connected to a damping adjustment mechanism, the damping adjustment mechanism comprises a generator, the generator input shaft is connected to the first transmission shaft, and the generator is connected to a rheostat.

16. A gear-synchronized polymer injection device according to any one of claims 2 to 14, characterized in that: The first transmission shaft or the second transmission shaft is connected to an output shaft of a driving device, and the driving device is an internal combustion engine or an electric motor.

17. A method for multi-stage continuous polymer injection using a gear-synchronized polymer injection device, characterized in that: The following steps are involved: S1. Connect the first transmission shaft or the second transmission shaft to the damping adjustment mechanism, connect the polymer liquid inlet pipe to the liquid inlet of the plunger seat, and connect the polymer output pipe to the liquid discharge port of the plunger seat; adjust the resistance through the damping adjustment mechanism according to the construction requirements; S2, press the polymer, the intermittent reversing mechanism connects the plunger seat liquid inlet with the piston sleeve, the polymer enters the piston sleeve through the plunger seat liquid inlet, pushes the first piston to move backward, and the first transmission shaft rotates. The first transmission shaft drives the second transmission shaft through the transmission mechanism, so that the intermittent reversing mechanism switches, disconnects the plunger seat liquid inlet from the piston sleeve, and connects the plunger seat liquid discharge port with the piston sleeve; S3, the first transmission shaft continues to rotate, pushing the first piston forward, so that the polymer in the piston sleeve enters the polymer output pipe and is injected into the formation, the intermittent reversing mechanism switches, the plunger seat liquid inlet is connected to the piston sleeve, the plunger seat liquid outlet is disconnected from the piston sleeve, and the circulation operation begins.

18. The method for multi-stage continuous polymer injection of a gear-synchronized polymer injection device according to claim 17, characterized in that: The resistance produced by the generator is adjusted by a rheostat in the damping adjustment mechanism; The polymer is pressed in, and there is a small-diameter contact between the cam and the fork. The lower sealing ring seals the discharge connection hole, the upper sealing ring is above the inlet connection hole, and the piston connection hole is above the lower sealing ring. The movement path of the polymer is through the plunger seat inlet, the inlet connection hole, the cavity between the upper and lower sealing rings, the piston connection hole, and the piston port, and enters the piston sleeve to push the first piston to move backward, drive the crankshaft to rotate, the crankshaft drives the gear shaft to rotate, and the gear shaft drives the camshaft to rotate, so that the contact between the cam and the fork changes from a small diameter to a large diameter contact, and the inlet and discharge plunger moves downward, so that the upper sealing ring seals the inlet connection hole, the lower sealing ring is below the discharge connection hole, and the piston connection hole is below the upper sealing ring; The crankshaft continues to rotate, pushing the first piston forward, causing the polymer in the piston sleeve to enter the polymer output pipe through the piston mouth, the piston connecting hole, the cavity between the upper and lower sealing rings, the drainage connecting hole, and the plunger seat drainage port, and be injected into the formation. The contact between the cam and the fork changes from large diameter to small diameter, and the circulation operation begins.

19. A method for continuous polymer injection of a gear-synchronized polymer injection device, characterized in that: The following steps are involved: S1, connecting the first transmission shaft or the second transmission shaft to the output shaft of the driving device, connecting the polymer liquid inlet pipe to the liquid inlet of the plunger seat, and connecting the polymer output pipe to the liquid discharge port of the plunger seat; S2, start the driving device, the first transmission shaft and the second transmission shaft start to rotate synchronously under the action of the rotating mechanism, the intermittent reversing mechanism connects the plunger seat liquid inlet with the piston sleeve, the first piston moves backward, generates negative pressure, and the polymer enters the piston sleeve through the plunger seat liquid inlet, the second transmission shaft continues to rotate, the intermittent reversing mechanism switches, the plunger seat liquid inlet is disconnected from the piston sleeve, and the plunger seat liquid discharge port is connected to the piston sleeve; S3, the first transmission shaft continues to rotate, pushing the first piston forward, so that the polymer in the piston sleeve enters the polymer output pipe and is injected into the formation, the intermittent reversing mechanism switches, the plunger seat liquid inlet is connected to the piston sleeve, the plunger seat liquid outlet is disconnected from the piston sleeve, and the circulation operation begins.

20. The method for continuous polymer injection of a gear-synchronized polymer injection device according to claim 19, characterized in that: The driving device is an internal combustion engine or an electric motor; When the first transmission shaft rotates, the crankshaft drives the first piston to move backward, generating negative pressure. The cam and the fork are in small-diameter contact, the lower sealing ring seals the discharge connection hole, the upper sealing ring is above the inlet connection hole, and the piston connection hole is above the lower sealing ring. The polymer enters the piston sleeve through the plunger seat inlet, the inlet connection hole, the cavity between the upper and lower sealing rings, the piston connection hole, and the piston port; at the same time, the camshaft rotates, causing the cam and the fork to change from small-diameter contact to large-diameter contact, and the inlet and discharge plunger moves downward, causing the upper sealing ring to seal the inlet connection hole, the lower sealing ring is below the discharge connection hole, and the piston connection hole is below the upper sealing ring; The crankshaft continues to rotate, causing the first piston to move forward, allowing the polymer in the piston sleeve to enter the polymer output pipe through the piston mouth, the piston connecting hole, the cavity between the upper and lower sealing rings, the drainage connecting hole, and the plunger seat drainage port, and be injected into the formation. The contact between the cam and the fork changes from large diameter to small diameter, and the circulation operation begins.

Images