PE full-coated sucker rod with anti-burst function

Abstract

The application belongs to the technical field of sucker rods, in particular to a PE full-coated sucker rod preventing explosion, which comprises a sucker rod body, a PE protective layer wrapped around the sucker rod body, a threaded hole arranged in the locking head, an explosion disc arranged in the threaded hole, a first air hole corresponding to the threaded hole arranged in the locking head, a gap between the sucker rod body and the PE protective layer being communicated with the other end of the first air hole, and a second air hole arranged through the compression bolt. The PE full-coated sucker rod preventing explosion is convenient for pressure relief treatment of the gap between the PE protective layer and the sucker rod body through the threaded hole, avoids the occurrence of the PE protective layer explosion phenomenon caused by excessive pressure, and effectively avoids the occurrence of the PE protective layer explosion damage phenomenon through the cooperation of the first air hole, the threaded hole and the second air hole, which can break the explosion disc when the pressure is too large and can perform pressure relief treatment.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of sucker rods, in particular to a PE full-coated sucker rod capable of preventing explosion. BACKGROUND

[0002] The sucker rod (also known as oil rod or pump rod) plays a role in oil production operation, which is to transmit the reciprocating motion provided by the ground equipment to the downhole oil pump, push the oil well to extract and lift the oil, and adjust the yield and pressure. In simple terms, its function is to transmit the up-and-down reciprocating motion of the ground to the downhole pump, make the pump work and pump oil, start and lift the oil in the well, send the oil to the ground, control the pumping rate and yield by adjusting the driving parameters (speed, falling stroke, etc.), and work with the downhole components (pump, valve, cavity, etc.) to ensure the sealing and wear control.

[0003] A PE full-coated sucker rod is disclosed in a Chinese patent with publication number CN222823185U. The PE full-coated sucker rod includes a sucker rod body, a connecting end fixedly installed at both left and right ends of the sucker rod body, a protective sleeve sleeved on the outer side of the sucker rod body, and an end sleeve sleeved on both left and right ends of the sucker rod body. The PE full-coated sucker rod is coated with a protective sleeve made of improved ultrahigh molecular polyethylene material on the outer side of the sucker rod body, which can better adapt to 1800-2000 meters of well section and has better wear resistance. The two ends of the sucker rod body are coated with end sleeves made of engineering plastic alloy material, which can make the sucker rod body have better high-temperature resistance, friction resistance, and corrosion resistance. By setting a limiting ring, an internal thread sleeve, an external thread sleeve, and a circular truncated cone ring sleeve in cooperation, the end sleeve at the end of the sucker rod body is extruded, making the connection between the end sleeve and the end of the sucker rod body more secure.

[0004] The coating layer of the PE full-coated sucker rod is made of ultrahigh molecular weight polyethylene, which has the characteristic of being impermeable to water, but small gas molecules can penetrate. After the sucker rod is lowered into the well, it is immersed in the produced liquid from the oil well. The dissolved methane gas in the produced liquid can slowly penetrate and diffuse into the PE coating layer, accumulating in the small gap space between the coating layer and the metal rod body. When the pressure of methane in the coating layer is equal to the hydraulic pressure in the oil pipe, the PE coating layer is sealed on the outside, and the methane gas can only slowly penetrate out. The gas pressure at the wellhead cannot be released in time, and when it approaches the wellhead, the pressure difference between the inside and outside of the PE coating layer is greater than the yield strength of the PE coating layer, and the gas expansion easily causes the PE coating layer to burst, affecting the service life.

[0005] Therefore, the application provides a PE full-coated sucker rod capable of preventing explosion. SUMMARY

[0006] In order to make up for the deficiency of the prior art, in order to solve the problem that the PE protective layer is damaged due to excessive pressure, the application provides a PE full-coated sucker rod capable of preventing explosion.

[0007] The technical scheme adopted by the application to solve the technical problem is: the PE full-coated sucker rod capable of preventing explosion comprises a sucker rod body, a PE protective layer is wrapped around the sucker rod body, a locking head is fixedly connected to the top end of the sucker rod body, a threaded hole is arranged in the locking head, an explosion disc is arranged in the threaded hole, a compression bolt is threadedly connected in the threaded hole, a first air hole corresponding to the threaded hole is arranged in the locking head, the first air hole is communicated with the threaded hole, a gap between the sucker rod body and the PE protective layer is communicated with the other end of the first air hole, and a second air hole is arranged in the compression bolt.

[0008] A cylinder is inlaid in the locking head, exhaust grooves are symmetrically connected to the cylinder, the other ends of the exhaust grooves extend out of the locking head, a sealing assembly is arranged in the exhaust grooves, exhaust assemblies are arranged in an array on the sucker rod body, an air extraction mechanism is arranged in the cylinder, and a driving mechanism is arranged at the top of the cylinder.

[0009] By adopting the above scheme, in the oil production operation, the explosion-proof PE full-coated sucker rod mainly transmits the mechanical power set on the ground to the oil well pump in the formation to realize the oil driving, extraction and lifting of the oil well. During use, the PE protective layer is wrapped around the sucker rod body, and the PE protective layer is used for protecting the surface of the sucker rod body. The main component of the gas in the oil well is methane, the PE protective layer is ultra-high molecular weight polyethylene, has the characteristic of water impermeability, but small gas molecules can penetrate, after the sucker rod body is lowered into the well, it is soaked in the produced fluid of the oil well, the small molecule gas of methane dissolved in the produced fluid can slowly penetrate and diffuse into the PE protective layer, and gather in the small gap space between the PE protective layer and the metal rod body of the sucker rod body, until the methane pressure in the PE protective layer is balanced with the hydraulic pressure in the oil pipe. When the rod is lifted, the PE protective layer expands with the decrease of the pressure in the oil pipe, the PE protective layer is sealed outside, the methane gas can only slowly penetrate out, and is lifted to the wellhead. The gas pressure cannot be released in time, when it approaches the wellhead, the pressure difference between the inside and outside of the PE protective layer is greater than the yield strength of the PE protective layer, the PE protective layer is blown up by the expansion of the gas. In order to avoid the damage of the PE protective layer, a threaded hole is arranged in the locking head, the first vent hole, the threaded hole and the second vent hole cooperate to make the gathered gas flow to the first vent hole, the gathered gas can be discharged through the threaded hole. The material of the bursting disc can be PE, the bursting disc is used to seal and protect the threaded hole, to prevent the produced fluid of the oil well from entering the threaded hole. According to the required bursting pressure, the thickness is set, when the gap between the PE protective layer and the sucker rod body gathers too much pressure during the lifting operation, the bursting disc will be broken, and the pressure relief can be carried out through the cooperation of the first vent hole, the threaded hole and the second vent hole, which can effectively avoid the damage of the PE protective layer. After the sucker rod body is taken out, only the compression bolt needs to be taken out, and a new bursting disc can be replaced.

[0010] Preferably, the exhaust assembly comprises an air inlet head, a flow pipe and a pipeline, the air inlet head is arranged in an array on the sucker rod body, the flow pipe corresponding to the air inlet head is arranged inside the sucker rod body, one end of the flow pipe is in communication with the air inlet head, the pipeline is embedded in the sucker rod body, the other end of the flow pipe is in communication with the pipeline, and the bottom of the cylinder is connected with a connecting head in communication with the cylinder.

[0011] By adopting the above scheme, the gas pressure gathered in the gap between the PE protective layer and the sucker rod body flows into the pipeline through the cooperation of the air inlet head and the flow pipe, the air inlet head is arranged in an array, which can comprehensively discharge and relieve the gathered pressure. Through the cooperation of the pipeline and the connecting head, the gas flows into the cylinder, drives the sealing assembly to move, and no longer seals the exhaust groove. The exhaust groove can be used for pressure relief, which can effectively avoid the damage of the PE protective layer caused by the excessive pressure of the gathered gas.

[0012] Preferably, the sealing assembly comprises a sealing block, a baffle and a reset assembly, the sealing block is engagedly arranged inside the exhaust groove, the baffle is fixedly connected with the side surface of the sealing block, the reset assembly for resetting the sealing block is arranged on the exhaust groove, and a sealing ring is arranged around the sealing block.

[0013] By adopting the above scheme, the sealing block and the sealing ring cooperate to seal the inside of the exhaust groove. After the gas flows into the cylinder through the pipeline and the connecting head, the gas flows into the exhaust groove, thereby pushing the sealing block to move out of the inside of the exhaust groove, so that the exhaust groove is no longer sealed. When the pressure relief is completed, the reset assembly resets the sealing block, and the exhaust groove is resealed and protected.

[0014] Preferably, the sealing block is rectangular, the outer surface of the sealing block is in close contact with the inner wall of the exhaust groove, and the sealing block is used for sealing the exhaust groove.

[0015] By adopting the above scheme, the sealing block and the sealing ring cooperate to seal and protect the inside of the exhaust groove.

[0016] Preferably, the reset assembly comprises a guide groove, a guide plate, a stop block, a square groove and a reset spring, the guide groove is symmetrically arranged on the exhaust groove, the guide plate is arranged inside the guide groove, one end of the guide plate is fixedly connected with the baffle, the stop block is fixedly arranged inside the guide groove, the square groove corresponding to the stop block is arranged inside the guide plate, the stop block is arranged inside the square groove, the reset spring is arranged inside the square groove, one end of the reset spring is fixedly connected with the inner wall of the square groove, and the other end of the reset spring is fixedly connected with the side surface of the stop block.

[0017] By adopting the above scheme, when the excessive gas pressure pushes the sealing block to move, the baffle drives the guide plate to move, the guide groove and the guide plate cooperate to make the baffle move stably, and the movement of the guide plate through the stop block cooperates to compress the reset spring. When the pressure relief is completed, the reset spring is reset, the square groove cooperates to push the guide plate to reset, and the guide plate moves to reset the sealing block through the baffle to seal the exhaust groove.

[0018] Preferably, the locking head is fixedly connected with a threaded head at the top, and the sucker rod body is fixedly connected with a threaded sleeve at the bottom.

[0019] By adopting the above scheme, the threaded head and the threaded sleeve cooperate to splice the sucker rod body.

[0020] Preferably, the air extraction mechanism comprises a sliding block, a protective box, a driving motor, a limiting block, a driving rod and a fan blade, the sliding block is arranged inside the cylinder, the protective box is arranged inside the sliding block, the driving motor is fixedly arranged inside the protective box, the limiting block is fixedly arranged at the bottom of the sliding block, the driving rod is rotatably arranged inside the limiting block, one end of the driving rod is fixedly connected with the output end of the driving motor, and the fan blade is fixedly arranged on the driving rod.

[0021] By adopting the above scheme, the gas enters the inside of the cylinder through the pipeline and the connecting head, and pushes the sliding block to move upwards. When the side surface of the sliding block no longer seals the exhaust groove after the sliding block moves upwards, the exhaust gas can be discharged through the exhaust groove. When the sliding block moves upwards to discharge pressure, the driving motor is sealed and protected by the protective box. The working of the driving motor drives the driving rod to rotate, which drives the fan blade to move. The movement of the fan blade assists the upward flow of the air pressure, which can further assist the pressure relief process and improve the pressure relief efficiency. The occurrence of damage to the PE protective layer is effectively avoided. The upward flow of the air pressure flows through the limiting block, which is conical, and guides the airflow, so that the gas flows into the exhaust groove. The exhaust groove discharges pressure.

[0022] Preferably, the top of the sliding block is fixedly connected with a driving plate, the driving mechanism comprises an annular groove, a limiting plate, a conductive cylinder, a first magnetic block, a conductive block and a power supply assembly, the annular groove is fixedly arranged at the top of the cylinder, one end of the driving plate extends into the annular groove, the limiting plate is arranged inside the annular groove, and the driving plate is fixedly connected with the limiting plate, the conductive cylinder is embedded in the top of the driving plate, and the conductive cylinder is electrically connected with the driving motor, the first magnetic block is fixedly arranged at the top of the inner wall of the annular groove, the conductive block is fixedly arranged at the bottom of the first magnetic block, and the conductive block is located directly above the conductive cylinder, the power supply assembly is fixedly arranged at the top of the annular groove, and the power supply assembly is electrically connected with the conductive block, and the second magnetic block is fixedly arranged on the driving plate.

[0023] By adopting the above scheme, when the sliding block moves upwards, the driving plate drives the limiting plate and the conductive cylinder to move synchronously. After the conductive block is inserted into the conductive cylinder, the second magnetic block moves below the first magnetic block, and the magnetic force generated by the two magnetic blocks limits the driving plate, so that the conductive cylinder and the conductive block are stably connected. The current flowing in the power supply assembly flows into the driving motor through the cooperation of the conductive block and the conductive cylinder, so that the driving motor works to drive the fan blade to move and assist the pressure relief process.

[0024] Preferably, a guide shaft is fixedly arranged inside the annular groove, a driving spring is arranged around the guide shaft, one end of the driving spring is fixedly connected with the top of the limiting plate, the other end of the driving spring is fixedly connected with the top of the inner wall of the annular groove, and a driving block is fixedly arranged on the sliding block.

[0025] By adopting the above scheme, when the driving plate pushes the limiting plate to move, the driving plate is guided and limited by the guide shaft, so that the driving plate moves stably, after pressure relief, the driving spring resets and pushes the limiting plate to reset, when the limiting plate resets, the first magnetic block and the second magnetic block are separated, at the same time, the electrically conductive cylinder and the electrically conductive block are separated, thereby the driving motor stops working, and at the same time, the sliding block resets to seal and protect the top of the connecting head.

[0026] Preferably, the locking head is internally inlaid with a strip-shaped groove corresponding to the exhaust groove, a push plate is arranged in the strip-shaped groove, the push plate is located directly above the top end of the driving block, a threaded cylinder is fixedly arranged in the push plate, an adjusting screw is rotatably arranged in the threaded cylinder, the adjusting screw is rotatably connected with the strip-shaped groove, and a knob is fixedly connected with the top end of the adjusting screw.

[0027] By adopting the above scheme, when the sliding block moves, the driving block moves synchronously, when the oil rod body is moved to the outside for disassembly, after the sliding block is not reset and the first magnetic block and the second magnetic block are separated, the knob can be rotated to drive the adjusting screw to rotate, the adjusting screw and the threaded cylinder cooperate to move the push plate, after the push plate moves downward and contacts the driving block, the sliding block is reset, and then the first magnetic block and the second magnetic block are separated.

[0028] The beneficial effects of the present application are as follows:

[0029] 1. The PE full-coated sucker rod of the present application is provided with a threaded hole, which is convenient for relieving the pressure accumulated in the gap between the PE protective layer and the oil rod body, effectively avoiding the explosion of the PE protective layer caused by excessive pressure, and the threaded hole, the first air hole, the threaded hole and the second air hole cooperate to make the accumulated gas flow to the first air hole, the accumulated gas can be discharged through the threaded hole, the bursting disc material can be PE, the bursting disc is used for sealing and protecting the threaded hole normally, avoiding the entry of external oil well production fluid into the threaded hole, the thickness is set according to the required bursting pressure, when the pressure accumulated in the gap between the PE protective layer and the oil rod body is too large during the operation of lifting the rod, the bursting disc will be broken, and then the first air hole, the threaded hole and the second air hole can be used for pressure relief, effectively avoiding the explosion and damage of the PE protective layer, and when the oil rod body is taken out, only the compression bolt needs to be taken out for replacement of the new bursting disc during repair.

[0030] 2. The PE full-coated sucker rod of the application prevents explosion, and the exhaust groove can further assist pressure relief. When the gap between the PE protective layer and the sucker rod body has excessive pressure, the pressure relief efficiency is low, and the air flows into the pipeline through the cooperation of the air inlet head and the flow pipe. The air inlet head is arranged in an array, which can comprehensively discharge and relieve the accumulated pressure. The gas flows into the cylinder through the cooperation of the pipeline and the connecting head, and the gas flows into the cylinder through the cooperation of the pipeline and the connecting head. The exhaust groove can discharge and relieve pressure, improve the pressure relief efficiency, and avoid damage to the PE protective layer caused by excessive pressure.

[0031] 3. The PE full-coated sucker rod of the application prevents explosion, and the exhaust groove can further assist pressure relief. When the gap between the PE protective layer and the sucker rod body has excessive pressure, the pressure relief efficiency is low, and the air flows into the pipeline through the cooperation of the air inlet head and the flow pipe. The air inlet head is arranged in an array, which can comprehensively discharge and relieve the accumulated pressure. The gas flows into the cylinder through the cooperation of the pipeline and the connecting head, and the gas flows into the cylinder through the cooperation of the pipeline and the connecting head. The exhaust groove can discharge and relieve pressure, improve the pressure relief efficiency, and avoid damage to the PE protective layer caused by excessive pressure.

[0032] 4. The PE full-coated sucker rod of the application prevents explosion, and the exhaust groove can further assist pressure relief. When the gap between the PE protective layer and the sucker rod body has excessive pressure, the pressure relief efficiency is low, and the air flows into the pipeline through the cooperation of the air inlet head and the flow pipe. The air inlet head is arranged in an array, which can comprehensively discharge and relieve the accumulated pressure. The gas flows into the cylinder through the cooperation of the pipeline and the connecting head, and the gas flows into the cylinder through the cooperation of the pipeline and the connecting head. The exhaust groove can discharge and relieve pressure, improve the pressure relief efficiency, and avoid damage to the PE protective layer caused by excessive pressure. BRIEF DESCRIPTION OF DRAWINGS

[0033] The application will be further described below with reference to the accompanying drawings.

[0034] Figure 1 is a perspective view of the PE full-coated sucker rod of the application;

[0035] Figure 2 is a structural schematic view of the sucker rod body in the application;

[0036] Figure 3 is a structural schematic view of the pipeline in the application;

[0037] Figure 4 is a structural schematic view of the PE protective layer in the application;

[0038] Figure 5It is the structure schematic view of locking head in the application;

[0039] Figure 6 It is the partial structure schematic view of sucker rod body and PE protective layer in the application;

[0040] Figure 7 It is the structure schematic view of the application Figure 6 It is the structure enlarged schematic view of A in the application;

[0041] Figure 8 It is the structure schematic view of exhaust groove in the application;

[0042] Figure 9 It is the structure schematic view of sealing block in the application;

[0043] Figure 10 It is the structure schematic view of cylinder in the application;

[0044] Figure 11 It is the structure schematic view of strip-shaped groove in the application.

[0045] In the figure: 1, sucker rod body; 2, locking head; 3, threaded head; 4, threaded sleeve; 5, PE protective layer; 6, threaded hole; 7, first air hole; 8, bursting disc; 9, compression bolt; 10, second air hole; 11, air inlet head; 12, flow pipe; 13, pipeline; 14, cylinder; 15, connecting head; 16, exhaust groove; 17, guide groove; 18, guide plate; 19, stop block; 20, square groove; 21, return spring; 22, sealing block; 23, sealing ring; 24, baffle; 25, sliding block; 26, protective box; 27, driving motor; 28, limiting block; 29, driving rod; 30, fan blade; 31, driving plate; 32, annular groove; 33, guide shaft; 34, limiting plate; 35, second magnetic block; 36, conductive cylinder; 37, first magnetic block; 38, conductive block; 39, power supply assembly; 40, strip-shaped groove; 41, push plate; 42, threaded cylinder; 43, adjusting screw; 44, knob; 45, driving block; 46, driving spring. DETAILED DESCRIPTION

[0046] In order to make the technical means, creative features, purposes and effects realized by the application easy to understand, the application is further described below in combination with specific embodiments.

[0047] As Figures 1 to 11The embodiment of the application shown is a PE full-coated sucker rod explosion-proof, which comprises a sucker rod body 1, a PE protective layer 5 wrapped around the sucker rod body 1, a locking head 2 fixedly connected to the top end of the sucker rod body 1, a threaded hole 6 arranged in the locking head 2, an explosion disc 8 arranged in the threaded hole 6, a compression bolt 9 threadedly connected in the threaded hole 6, a first air hole 7 arranged in the locking head 2 corresponding to the threaded hole 6, the first air hole 7 being in communication with the threaded hole 6, the gap between the sucker rod body 1 and the PE protective layer 5 being in communication with the other end of the first air hole 7, and a second air hole 10 arranged through the compression bolt 9.

[0048] A cylinder 14 is inlaid in the locking head 2, the cylinder 14 is symmetrically connected with an exhaust groove 16, the other end of the exhaust groove 16 extends out of the locking head 2, a sealing assembly is arranged in the exhaust groove 16, an exhaust assembly is arranged in an array on the sucker rod body 1, an air extraction mechanism is arranged in the cylinder 14, and a driving mechanism is arranged on the top of the cylinder 14.

[0049] In the oil production operation, the explosion-proof PE full-coated sucker rod mainly transmits the mechanical power set on the ground to the oil well pump in the formation to realize the oil driving, extraction and lifting of the oil well. During use, the PE protective layer 5 is wrapped around the sucker rod body 1, which is used to protect the surface of the sucker rod body 1. The main component of the gas in the oil well is methane, and the PE protective layer 5 is made of ultra-high molecular weight polyethylene, which has the characteristic of being impermeable to water, but small gas molecules can penetrate. After the sucker rod body 1 is lowered into the well, the small molecule gas of methane dissolved in the produced fluid can slowly penetrate and diffuse into the PE protective layer 5, and gather in the small gap space between the PE protective layer 5 and the metal rod body of the sucker rod body 1, until the methane pressure in the PE protective layer 5 is balanced with the hydraulic pressure in the oil pipe. The pressure of methane penetrating into the coating layer in a 1500-meter well section reaches 15 MPa, and the deeper the well, the higher the pressure. When the rod is lifted, the sucker rod body 1 is lifted at a relatively fast speed, and the methane in the PE protective layer 5 expands as the pressure in the oil pipe decreases. The PE protective layer 5 is sealed to the outside, and the methane gas can only slowly penetrate out. It takes less than an hour to lift from 1500 meters deep to the wellhead, and the gas pressure cannot be released in time. When it approaches the wellhead, the pressure difference between the inside and outside of the PE protective layer 5 is greater than the yield strength of the PE protective layer 5, and the gas expansion blows up the PE coating layer. In order to avoid damage to the PE protective layer 5, a threaded hole 6, a first vent hole 7, a threaded hole 6 and a second vent hole 10 are provided in the locking head 2. The gathered gas flows to the first vent hole 7, and the gathered gas is discharged through the threaded hole 6. The bursting disc 8 is made of PE, and is used to seal and protect the threaded hole 6 from the outside oil well production fluid. The thickness of the bursting disc 8 is set according to the required bursting pressure. When the gap between the PE protective layer 5 and the sucker rod body 1 gathers too much pressure, the bursting disc 8 will be broken, and the pressure relief can be carried out through the cooperation of the first vent hole 7, the threaded hole 6 and the second vent hole 10, effectively avoiding the damage of the PE protective layer 5. After the sucker rod body 1 is taken out, only the compression bolt 9 needs to be taken out and the new bursting disc 8 needs to be replaced for repair;

[0050] During use of the sucker rod body 1, the threaded hole 6 can also be sealed with glue. Due to the small strength of the glue, the bursting pressure is small, and the threaded hole 6 needs to be cleaned for on-site repair after bursting, and can be recycled;

[0051] A rubber plug can also be placed in the threaded hole 6 for sealing when pressure relief. The rubber plug plays a sealing role, and the hole can be plugged with a new rubber plug on site for simple repair;

[0052] When the gap between the PE protective layer 5 and the sucker rod body 1 gathers excessive pressure, and the pressure relief efficiency is not high only through the threaded hole 6, the excessive pressure can be quickly relieved through the cooperation of the exhaust assembly, the air exhaust mechanism and the exhaust groove 16, and the occurrence of the PE protective layer 5 blasting phenomenon caused by excessive pressure can be further avoided, and the service life of the explosion-proof PE fully-coated sucker rod is improved.

[0053] Further, the exhaust assembly comprises an air inlet head 11, a flow pipe 12 and a pipeline 13, the air inlet head 11 is arranged in an array on the sucker rod body 1, the flow pipe 12 corresponding to the air inlet head 11 is arranged inside the sucker rod body 1, and one end of the flow pipe 12 is in communication with the air inlet head 11, the pipeline 13 is embedded inside the sucker rod body 1, and the other end of the flow pipe 12 is in communication with the pipeline 13, and the bottom of the cylinder 14 is connected with a connecting head 15, and the connecting head 15 is in communication with the cylinder 14;

[0054] The gas pressure gathered in the gap between the PE protective layer 5 and the sucker rod body 1 will flow into the pipeline 13 through the cooperation of the air inlet head 11 and the flow pipe 12, the air inlet head 11 is arranged in an array, and the gathered pressure can be discharged and relieved comprehensively, and the gas will flow into the cylinder 14 through the cooperation of the pipeline 13 and the connecting head 15, drive the sealing assembly to move, and no longer seal the exhaust groove 16, so that the exhaust groove 16 can be relieved, and the PE protective layer 5 can be effectively prevented from being damaged due to excessive gas gathering pressure.

[0055] Further, the sealing assembly comprises a sealing block 22, a baffle 24 and a reset assembly, the sealing block 22 is clamped and arranged inside the exhaust groove 16, the baffle 24 is fixedly connected with the side surface of the sealing block 22, the reset assembly for resetting the sealing block 22 is arranged on the exhaust groove 16, and the sealing ring 23 is arranged around the sealing block 22;

[0056] The sealing block 22 and the sealing ring 23 cooperate to seal the inside of the exhaust groove 16, after the gas flows into the cylinder 14 through the cooperation of the pipeline 13 and the connecting head 15, the gas will flow into the exhaust groove 16, and then push the sealing block 22 to move, after the sealing block 22 moves out of the inside of the exhaust groove 16, the exhaust groove 16 is no longer sealed, and after the relief is completed, the sealing block 22 is reset through the reset assembly, and the exhaust groove 16 can be resealed and protected.

[0057] Further, the sealing block 22 is rectangular, the outer surface of the sealing block 22 is in close contact with the inner wall of the exhaust groove 16, the sealing block 22 is used for sealing the exhaust groove 16, and the sealing block 22 and the sealing ring 23 cooperate to seal and protect the inside of the exhaust groove 16.

[0058] Further, the reset assembly includes a guide groove 17, a guide plate 18, a stop block 19, a square groove 20 and a reset spring 21. The guide groove 17 is symmetrically arranged on the exhaust groove 16, the guide plate 18 is arranged in the guide groove 17, one end of the guide plate 18 is fixedly connected with the baffle 24, the stop block 19 is fixedly arranged in the guide groove 17, the square groove 20 corresponding to the stop block 19 is arranged in the guide plate 18, the stop block 19 is arranged in the square groove 20, the reset spring 21 is arranged in the square groove 20, one end of the reset spring 21 is fixedly connected with the inner wall of the square groove 20, and the other end of the reset spring 21 is fixedly connected with the side surface of the stop block 19. When the sealing block 22 is pushed to move due to excessive gas pressure, the baffle 24 will drive the guide plate 18 to move, the baffle 24 will move stably through the cooperation of the guide groove 17 and the guide plate 18, and the guide plate 18 will move through the cooperation of the stop block 19 to compress the reset spring 21. When the pressure relief is completed, the reset spring 21 is reset, the guide plate 18 is reset through the cooperation of the square groove 20, and the guide plate 18 is reset to seal the exhaust groove 16 through the baffle 24.

[0059] Further, the locking head 2 is fixedly connected with a threaded head 3, and the sucker rod body 1 is fixedly connected with a threaded sleeve 4 at the bottom end.

[0060] The sucker rod body 1 can be spliced through the cooperation of the threaded head 3 and the threaded sleeve 4.

[0061] Further, the air extraction mechanism includes a sliding block 25, a protection box 26, a driving motor 27, a limiting block 28, a driving rod 29 and a fan blade 30. The sliding block 25 is arranged in the cylinder 14, the protection box 26 is arranged in the sliding block 25, the driving motor 27 is fixedly arranged in the protection box 26, the limiting block 28 is fixedly arranged at the bottom of the sliding block 25, the driving rod 29 is rotatably arranged in the limiting block 28, one end of the driving rod 29 is fixedly connected with the output end of the driving motor 27, and the fan blade 30 is fixedly arranged on the driving rod 29. The limiting block 28 is in the shape of a cone.

[0062] Through the cooperation of the pipeline 13 and the connecting head 15, the gas enters the inside of the cylinder 14, pushes the sliding block 25 to move upwards, and the exhaust groove 16 is no longer sealed by the side surface of the sliding block 25 when the sliding block 25 moves upwards, so that the exhaust groove 16 can be used for exhaust pressure relief. When the sliding block 25 moves upwards to relieve pressure, the protection box 26 can seal and protect the driving motor 27, so that the driving motor 27 works to drive the driving rod 29 to rotate, the driving rod 29 rotates to drive the fan blade 30 to move, the fan blade 30 moves to assist the upward flow of the gas pressure, which can further assist the pressure relief process and improve the pressure relief efficiency, effectively avoiding the damage of the PE protective layer 5. The upward flow of the gas pressure flows through the limiting block 28, the limiting block 28 is in the shape of a cone, can guide the airflow, and makes the gas flow into the inside of the exhaust groove 16, which is relieved through the exhaust groove 16.

[0063] Further, the top of the sliding block 25 is fixedly connected with a driving plate 31. The driving mechanism comprises an annular groove 32, a limiting plate 34, a conductive cylinder 36, a first magnetic block 37, a conductive block 38 and a power supply assembly 39. The annular groove 32 is fixedly arranged at the top of the cylinder 14. One end of the driving plate 31 extends into the annular groove 32. The limiting plate 34 is arranged in the annular groove 32. The driving plate 31 is fixedly connected with the limiting plate 34. The conductive cylinder 36 is inlaid at the top of the driving plate 31. The conductive cylinder 36 is electrically connected with the driving motor 27. The first magnetic block 37 is fixedly arranged at the top of the inner wall of the annular groove 32. The conductive block 38 is fixedly arranged at the bottom of the first magnetic block 37. The conductive block 38 is located directly above the conductive cylinder 36. The power supply assembly 39 is fixedly arranged at the top of the annular groove 32. The power supply assembly 39 is electrically connected with the conductive block 38. The second magnetic block 35 is fixedly arranged on the driving plate 31.

[0064] When the sliding block 25 moves upwards, the limiting plate 34 and the conductive cylinder 36 are driven to move synchronously by the driving plate 31. When the conductive block 38 is inserted into the conductive cylinder 36, the second magnetic block 35 moves below the first magnetic block 37. The magnetic force generated by the two blocks limits the driving plate 31, so that the conductive cylinder 36 and the conductive block 38 are stably connected. The current in the power supply assembly 39 flows into the driving motor 27 through the cooperation of the conductive block 38 and the conductive cylinder 36, so that the driving motor 27 works to drive the fan blade 30 to move, thereby assisting the pressure relief process.

[0065] Further, a guide shaft 33 is fixedly arranged in the annular groove 32. A driving spring 46 is arranged around the guide shaft 33. One end of the driving spring 46 is fixedly connected with the top of the limiting plate 34. The other end of the driving spring 46 is fixedly connected with the top of the inner wall of the annular groove 32. A driving block 45 is fixedly arranged on the sliding block 25.

[0066] When the driving plate 31 drives the limiting plate 34 to move, the driving plate 31 is guided and limited by the guide shaft 33, so that the driving plate 31 moves stably. After the pressure relief, the driving spring 46 resets to drive the limiting plate 34 to reset. When the limiting plate 34 resets, the first magnetic block 37 and the second magnetic block 35 are separated, and the conductive cylinder 36 and the conductive block 38 are also separated, so that the driving motor 27 stops working. At the same time, the sliding block 25 resets to seal and protect the top of the connecting head 15.

[0067] Further, a strip-shaped groove 40 corresponding to the exhaust groove 16 is inlaid in the locking head 2. A push plate 41 is arranged in the strip-shaped groove 40. The push plate 41 is located directly above the top end of the driving block 45. A threaded cylinder 42 is fixedly arranged in the push plate 41. An adjusting screw 43 is rotatably arranged in the threaded cylinder 42. The adjusting screw 43 is rotatably connected with the strip-shaped groove 40. A knob 44 is fixedly connected with the top end of the adjusting screw 43.

[0068] When the sliding block 25 moves, the driving block 45 moves synchronously. When the sucker rod body 1 moves to the outside for disassembly, the sliding block 25 is not reset to separate the first magnetic block 37 and the second magnetic block 35. The rotating knob 44 drives the adjusting screw 43 to rotate. The adjusting screw 43 and the threaded cylinder 42 cooperate to move the push plate 41. The push plate 41 moves downward and contacts the driving block 45, which pushes the sliding block 25 to reset, thereby separating the first magnetic block 37 and the second magnetic block 35.

[0069] Working principle: first in the oil production operation, the explosion-proof PE full-coated sucker rod is mainly to transmit the mechanical power set on the ground to the oil well pump in the formation to realize the oil driving, pumping and lifting of the oil well. During use, the PE protective layer 5 is wrapped around the sucker rod body 1, which is used to protect the surface of the sucker rod body 1. The main component of the gas in the oil well is methane, and the PE protective layer 5 is made of ultra-high molecular weight polyethylene, which has the characteristic of being impermeable to water, but small gas molecules can penetrate. After the sucker rod body 1 is lowered into the well, it is immersed in the produced fluid, and the small molecule gas of methane dissolved in the produced fluid can slowly penetrate and diffuse into the PE protective layer 5, and gather in the small gap space between the PE protective layer 5 and the metal rod body of the sucker rod body 1. When the pressure of methane in the PE protective layer 5 is equal to the hydraulic pressure in the oil pipe, the pressure of methane penetrating into the coating layer in the 1500-meter well section reaches 15 MPa, and the deeper the pressure is higher. When the rod is lifted, the sucker rod body 1 is lifted at a relatively fast speed, and the methane in the PE protective layer 5 expands as the pressure in the oil pipe decreases. The PE protective layer 5 is sealed to the outside, and the methane gas can only slowly penetrate out. It takes less than an hour to lift from 1500 meters deep to the wellhead, and the gas pressure cannot be released in time. When it approaches the wellhead, the pressure difference between the inside and outside of the PE protective layer 5 is greater than the yield strength of the PE protective layer 5, and the gas expansion blows up the PE coating layer. In order to avoid damage to the PE protective layer 5, a threaded hole 6 is arranged in the locking head 2. The cooperation of the first vent hole 7, the threaded hole 6 and the second vent hole 10 will make the gathered gas flow to the first vent hole 7, and the gathered gas can be discharged through the threaded hole 6. The material of the rupture disc 8 can be PE. The rupture disc 8 is usually used to seal and protect the threaded hole 6 to prevent the produced fluid from entering the inside of the threaded hole 6. According to the required burst pressure, the thickness is set. When the gap between the PE protective layer 5 and the sucker rod body 1 gathers too much pressure during the operation of lifting the rod, the rupture disc 8 will be broken, and the pressure relief can be carried out through the cooperation of the first vent hole 7, the threaded hole 6 and the second vent hole 10, which can effectively avoid the damage of the PE protective layer 5. After the sucker rod body 1 is taken out, only the compression bolt 9 needs to be taken out and the new rupture disc 8 needs to be replaced during repair. During the use of the sucker rod body 1, the threaded hole 6 can also be sealed with glue. Because the strength of the glue is small, the burst pressure is small, and the threaded hole 6 needs to be cleaned after on-site repair after the burst, it can be recycled. When the pressure is released, a rubber plug can be placed in the threaded hole 6 to seal the hole. As long as a new rubber plug is used to plug the hole on site, the repair is simple. When the gap between the PE protective layer 5 and the sucker rod body 1 gathers too much pressure, the pressure relief efficiency is not high through the threaded hole 6. Through the cooperation of the air inlet head 11 and the flow pipe 12, it will flow into the pipe 13. The air inlet head 11 is arranged in an array, which can discharge and relieve the pressure gathered comprehensively. Through the cooperation of the pipe 13 and the connecting head 15, the gas will flow into the cylinder 14. Through the cooperation of the pipe 13 and the connecting head 15, the gas will enter the cylinder 14.The sliding block 25 is pushed upward, and when the side of the sliding block 25 no longer seals the exhaust groove 16, exhaust pressure relief can be performed through the exhaust groove 16. When the sliding block 25 is moved upward, the driving plate 31 drives the limiting plate 34 and the conductive cylinder 36 to move synchronously. The conductive cylinder 36 moves, and after the conductive block 38 is inserted into the conductive cylinder 36, the second magnetic block 35 moves below the first magnetic block 37. The magnetic force generated by the two blocks limits the driving plate 31, so that the conductive cylinder 36 and the conductive block 38 are stably connected. The current in the power supply assembly 39 flows into the driving motor 27 through the cooperation of the conductive block 38 and the conductive cylinder 36, so that the driving motor 27 works to drive the fan blade 30 to move. When the fan blade 30 moves, it will assist the upward flow of air pressure, which can further assist the pressure relief process and improve the pressure relief efficiency. The phenomenon of damage to the PE protective layer 5 is effectively avoided. The upward flow of air pressure flows through the limiting block 28, which is conical, and guides the airflow so that the gas flows into the exhaust groove 16. The exhaust groove 16 can be relieved, which can quickly relieve pressure and further avoid the occurrence of PE protective layer 5 blasting caused by excessive pressure, thereby improving the service life of the explosion-proof PE full-coated sucker rod. After pressure relief, the driving spring 46 resets and pushes the limiting plate 34 to reset. When the limiting plate 34 resets, the first magnetic block 37 and the second magnetic block 35 are separated, and the conductive cylinder 36 and the conductive block 38 are separated, so that the driving motor 27 stops working, and the sliding block 25 resets to seal and protect the top of the connector 15.

[0070] The basic principles, main features and advantages of the present application are shown and described above. Those skilled in the art should understand that the present application is not limited to the above embodiments, and the above embodiments and descriptions in the specification are only to illustrate the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. An explosion-proof PE full-coated sucker rod, characterized in that: Including sucker rod body (1), the PE protective layer (5) is wrapped around on the sucker rod body (1), the sucker rod body (1) top end fixedly connected with locking head (2), locking head (2) inside is provided with threaded hole (6), threaded hole (6) inside is provided with bursting disc (8), threaded hole (6) inside is connected with the compression bolt (9) of screw thread, locking head (2) inside is provided with with threaded hole (6) corresponding one vent hole (7), and one vent hole (7) is communicated with threaded hole (6), the gap between sucker rod body (1) and PE protective layer (5) is communicated with one vent hole (7) other end, the compression bolt (9) inside is provided with the second vent hole (10) of through, the locking head (2) is inlayed with cylinder (14), cylinder (14) is connected with exhaust groove (16) on symmetry, and exhaust groove (16) other end extends out locking head (2), exhaust groove (16) inside is provided with sealing assembly, the sucker rod body (1) is provided with exhaust assembly on array, the cylinder (14) is provided with air extraction mechanism inside, and the cylinder (14) top is provided with drive mechanism; The locking head (2) top fixedly connected with threaded head (3), the sucker rod body (1) bottom end fixedly connected with threaded sleeve (4); The air extraction mechanism includes sliding block (25), protection box (26), drive motor (27), limit block (28), drive rod (29) and fan blade (30), the cylinder (14) is provided with sliding block (25) inside, the protection box (26) is arranged in sliding block (25), the drive motor (27) is fixedly arranged in the protection box (26) inside, the limit block (28) is fixedly arranged in the bottom of sliding block (25), the drive rod (29) is rotatably arranged in the limit block (28) inside, and the drive rod (29) one end is fixedly connected with the output end of drive motor (27), the fan blade (30) is fixedly arranged on the drive rod (29), and the limit block (28) is conical in shape; The sliding block (25) top fixedly connected with drive plate (31), the drive mechanism includes annular groove (32), limit plate (34), conducting cylinder (36), one magnetic block (37), conducting block (38) and power supply assembly (39), the annular groove (32) is fixedly arranged at the top of cylinder (14), and one end of drive plate (31) extends to the inside of annular groove (32), the limit plate (34) is arranged in annular groove (32), and drive plate (31) is fixedly connected with limit plate (34), conducting cylinder (36) is embedded in the top of drive plate (31), and conducting cylinder (36) is electrically connected with drive motor (27), one magnetic block (37) is fixedly arranged on the top of the inner wall of annular groove (32), conducting block (38) is fixedly arranged on the bottom of one magnetic block (37), and conducting block (38) is located directly above conducting cylinder (36), power supply assembly (39) is fixedly arranged at the top of annular groove (32), and power supply assembly (39) is electrically connected with conducting block (38), and the second magnetic block (35) is fixedly arranged on drive plate (31). ​ 2. The explosion-proof PE fully-coated sucker rod according to claim 1, characterized in that: The exhaust assembly comprises an air inlet head (11), a flow pipe (12) and a pipeline (13), the air inlet head (11) is arranged on the sucker rod body (1) in an array, the flow pipe (12) corresponding to the air inlet head (11) is arranged inside the sucker rod body (1) and is in communication with the air inlet head (11) at one end, the pipeline (13) is embedded inside the sucker rod body (1), the flow pipe (12) is in communication with the pipeline (13) at the other end, and the bottom of the cylinder (14) is connected with a connecting head (15) in communication with the cylinder (14).

3. The explosion-proof PE fully-coated sucker rod according to claim 2, characterized in that: The sealing assembly comprises a sealing block (22), a baffle (24) and a reset assembly, the sealing block (22) is clamped and arranged inside the exhaust groove (16), the baffle (24) is fixedly connected with the side surface of the sealing block (22), the reset assembly for resetting the sealing block (22) is arranged on the exhaust groove (16), and the sealing ring (23) is arranged around the sealing block (22).

4. The explosion-proof PE fully-coated sucker rod according to claim 3, characterized in that: The sealing block (22) is rectangular, the outer surface of the sealing block (22) is in close contact with the inner wall of the exhaust groove (16), and the sealing block (22) is used for sealing the exhaust groove (16).

5. The explosion-proof PE fully-coated sucker rod according to claim 4, characterized in that: The reset assembly comprises a guide groove (17), a guide plate (18), a stop block (19), a square groove (20) and a reset spring (21), the guide grooves (17) are symmetrically arranged on the exhaust groove (16), the guide plate (18) is arranged in the guide groove (17), one end of the guide plate (18) is fixedly connected with the baffle (24), the stop block (19) is fixedly arranged in the guide groove (17), the square groove (20) corresponding to the stop block (19) is arranged in the guide plate (18), the stop block (19) is arranged in the square groove (20), the reset spring (21) is arranged in the square groove (20), one end of the reset spring (21) is fixedly connected with the inner wall of the square groove (20), and the other end of the reset spring (21) is fixedly connected with the side surface of the stop block (19).

6. The explosion-proof PE fully-coated sucker rod according to claim 1, characterized in that: The guide shaft (33) is fixedly arranged in the annular groove (32), the driving spring (46) is arranged around the guide shaft (33), one end of the driving spring (46) is fixedly connected with the top of the limiting plate (34), the other end of the driving spring (46) is fixedly connected with the top of the inner wall of the annular groove (32), and the driving block (45) is fixedly arranged on the sliding block (25).

7. The explosion-proof PE fully-coated sucker rod according to claim 6, characterized in that: The locking head (2) is embedded with the strip-shaped groove (40) corresponding to the exhaust groove (16) inside, the push plate (41) is arranged in the strip-shaped groove (40), the push plate (41) is located directly above the top end of the driving block (45), the threaded cylinder (42) is fixedly arranged in the push plate (41), the adjusting screw rod (43) is rotatably arranged in the threaded cylinder (42), the adjusting screw rod (43) is rotatably connected with the strip-shaped groove (40), and the knob (44) is fixedly connected with the top end of the adjusting screw rod (43).

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