A wellhead Christmas tree with flow rate overload shut-off function for oil field production wells

Abstract

The present invention relates to a wellhead Christmas tree, and in particular to a wellhead Christmas tree with a flow rate overload closing function for oil field production wells. The technical problem of the present invention is that the Christmas tree cannot be closed when the crude oil increases abnormally, and the sucker rod continues to work to extract crude oil during a blowout, which will cause a larger range of crude oil blowouts. It includes a lower valve body, a delivery pipeline, an upper valve body, a closing mechanism, etc.; the upper part of the lower valve body is provided with a delivery pipeline, the upper part of the delivery pipeline is provided with an upper valve body, and the upper part of the delivery pipeline is provided with a closing mechanism. The present invention completes a double-layer closure of the delivery pipeline through a closing mechanism to avoid the inability to close the delivery pipeline during a crude oil blowout, resulting in crude oil leakage. At the same time, the positioning mechanism fixes the limit of the sucker rod to avoid the sucker rod continuing to work when a crude oil blowout occurs, and the reset mechanism restores the device to the initial position to release the limit on the sucker rod.

Description

Technical Field

[0001] The invention relates to the field of oil field production equipment, in particular to a wellhead Christmas tree with a flow rate overload shut-off function for an oil field production well. Background Art

[0002] The Christmas tree is a wellhead device used to extract oil in self-flowing wells and machine-drilling wells. It is the main equipment at the top of the oil and gas well to control and regulate oil and gas production. It mainly consists of three parts: casing head, tubing head, and Christmas tree body.

[0003] During the crude oil extraction process, the fluidity of the extracted crude oil is unstable due to the influence of the environment and the extraction equipment. Since the crude oil is extracted from different regions, the crude oil from different regions has different internal components, which will cause the extracted crude oil to have different component contents. After the extracted crude oil enters the Christmas tree, the extracted crude oil is extracted as the sucker rod works, which will cause multiple pressure changes in the Christmas tree. The existing Christmas tree cannot be closed in time when the crude oil increase is abnormal. When the crude oil blows out, it will cause crude oil leakage. In addition, during the blowout, since the sucker rod is not fixed, the sucker rod continues to work to extract crude oil, which will cause a larger range of crude oil blowouts.

[0004] Therefore, it is urgent to develop a wellhead Christmas tree with a flow rate overload shutdown function for oil field production wells. Summary of the invention

[0005] In order to overcome the disadvantages that the Christmas tree cannot be closed when the oil increase is abnormal, and the sucker rod continues to work to extract crude oil during a blowout, which will cause a larger range of crude oil blowouts, the technical problem of the present invention is to provide a wellhead Christmas tree with a flow rate overload shutdown function for an oil field production well.

[0006] A wellhead Christmas tree with a flow rate overload closing function for an oil field production well, comprising a lower valve body, a delivery pipeline, an upper valve body, a closing mechanism, a positioning mechanism and a resetting mechanism, comprising a lower valve body, a delivery pipeline and an upper valve body, a delivery pipeline is arranged on the upper part of the lower valve body, an upper valve body is arranged on the upper part of the delivery pipeline, flank oil pipelines are arranged on both sides of the upper valve body and the lower valve body, the lower valve body, the delivery pipeline, the upper valve body and the flank oil pipelines cooperate to form a Christmas tree, a closing mechanism is arranged on the upper part of the delivery pipeline, the closing mechanism is used to block the delivery pipeline, positioning mechanisms are arranged on both sides of the middle part of the delivery pipeline, and the positioning mechanisms are used to The oil rod limit is fixed, and a filter screen is arranged at the lower part of the conveying pipeline, and the filter screen is used to filter crude oil. The sucker rod passes through the filter screen and slides with it, and the sucker rod passes through the top of the upper valve body and slides and seals with it. A reset mechanism is arranged on the conveying pipeline, and the reset mechanism is used to release the fixed limit of the sucker rod. The present invention completes the double-layer sealing of the conveying pipeline through the cooperation of the closing mechanism, the positioning mechanism and the reset mechanism, so as to avoid the failure to close the conveying pipeline when crude oil blows out, resulting in crude oil leakage. At the same time, the limit of the sucker rod is fixed to avoid the sucker rod continuing to work when crude oil blows out, and the device is restored to the initial position to release the limit of the sucker rod.

[0007] Furthermore, the closing mechanism includes a fixed shell, a guide rod, a sealing shell, a first spring, a hollow sealing frame, a disc, a fixed tube, an inner shell, a connecting frame, an arc-shaped limit rod and a sealing assembly. The fixed shell is fixedly connected to the upper inner part of the conveying pipeline, and the front and rear parts of the lower surface of the fixed shell are connected to the guide rod, and a sealing shell is slidably provided at the lower parts of the guide rods on the front and rear sides. Two first springs are fixedly connected between the sealing shell and the fixed shell, and the first springs on the front and rear sides are respectively sleeved on the outer sides of the guide rods on the front and rear sides. A hollow sealing frame is slidably provided inside the sealing shell and the fixed shell, and the middle part of the hollow sealing frame is provided with a cavity. Four circular holes penetrating downward are circumferentially provided on the upper surface of the hollow sealing frame, and the cavity of the hollow sealing frame is connected with the circular hole. A disc is slidably provided in the cavity of the hollow sealing frame, and four discharge holes penetrating downward are circumferentially provided on the upper surface of the disc. The diameter of the material hole is equal to that of the circular hole on the hollow sealing frame. A fixed tube is fixedly connected between the inner side surfaces of the upper and lower adjacent hollow sealing frames. An inner shell is slidably arranged in the fixed tube. The upper and lower parts of the inner shell are respectively slidably connected with the hollow sealing frames passing through the upper and lower sides. The upper and lower parts of the inner shell are respectively fixedly connected with the discs on the upper and lower sides. A connecting frame is installed on the lower surface of the inner shell. Arc-shaped limiting rods are installed on the front and rear sides of the lower part of the connecting frame. A sealing assembly is arranged on the upper part of the sealing shell. The sealing assembly passes through the fixed tube and cooperates with the inner shell. The sucker rod passes through the hollow sealing frame, the disc, the inner shell, the hollow sealing frame and the connecting frame on the lower side and is slidably sealed with them. The fixed shell and the sealing shell are respectively cooperated with the hollow sealing frames on the upper and lower sides to form a double-layer closure of the conveying pipeline, so as to avoid the conveying pipeline from being unable to be closed during crude oil blowout, resulting in crude oil leakage.

[0008] Furthermore, the outer side of the hollow sealing frame is provided with a plurality of triangular blocks, and the upper inner part of the fixed shell and the sealing shell are provided with a plurality of triangular blocks, and the fixed shell and the sealing shell are respectively slidably sealed with the hollow sealing frame on the upper and lower sides.

[0009] The seal assembly comprises a rotating plate, a torsion spring, a connecting plate, an L-shaped rod and a second spring. The front and rear sides of the upper inner portion of the sealing shell are rotatably mounted with a rotating plate through a rotating rod. The left and right rotating rods of the rotating plate are sleeved with torsion springs. The two ends of the torsion spring are respectively fixed to the sealing shell and the rotating plate. The front and rear parts of the sealing shell are both mounted with two connecting plates. An L-shaped rod is slidably arranged between the upper and lower adjacent connecting plates. The front and rear parts of the lower side surface of the fixed tube are both provided with upwardly extending sliding grooves. The front and rear L-shaped rods on the front and rear sides respectively pass through the sliding grooves on the front and rear sides of the fixed tube and slide with it. The upper part of the L-shaped rod is fixedly connected with two second springs. The upper and lower adjacent second springs are fixedly connected to the connecting plate. The front and rear lower sides of the inner shell are both provided with oblique grooves. The front and rear L-shaped rods on the front and rear sides are respectively slidably matched with the front and rear oblique grooves on the front and rear sides of the inner shell. The inner shell is moved upward by utilizing the cooperation of the L-shaped rod and the inner shell, so that the disc is rotated to close the hollow sealing frame, thereby completing the double-layer closure of the conveying pipeline, thereby preventing the conveying pipeline from being unable to be closed during crude oil blowout, resulting in crude oil leakage.

[0010] Furthermore, the positioning mechanism includes an arc block, an n-shaped plate, a sliding rod, a clamping block, a third spring, a screw, a worm gear, a mounting frame, a worm, a hollow shell, a first bevel gear, a first rotating shaft, a second bevel gear, a guide roller, a third bevel gear, a limit assembly and a reset assembly. An arc block is slidably provided on the rear side of the middle part of the conveying pipeline, and an arc groove extending backward is provided on the front side of the arc block for clamping and limiting the sucker rod. An n-shaped plate is installed on the upper surface of the arc block, and a sliding rod is slidably provided on the upper surface of the n-shaped plate. A clamping block is fixedly connected to the upper end of the sliding rod, and a third spring is fixedly connected between the clamping block and the n-shaped plate. The third spring is sleeved on the outside of the sliding rod, and a rectangular groove is provided downwardly in the middle part of the upper surface of the arc block. A screw is rotatably installed in the middle part of the arc block, and the screw is located in the rectangular groove of the arc block. A worm gear is threadedly connected to the screw, and a worm gear is provided at the rear of the worm gear. A mounting frame is provided, a worm is rotatably mounted on the upper part of the mounting frame, the worm is meshed with the worm wheel, a hollow shell is rotatably mounted on the left and right walls of the mounting frame, a first bevel gear is mounted on the left and right parts of the worm, a first rotating shaft is rotatably mounted in the hollow shell, second bevel gears are mounted on the upper and lower ends of the first rotating shaft, the adjacent second bevel gears are meshed with the first bevel gear, a guide roller is rotatably mounted between the left and right adjacent hollow shells, a third bevel gear is mounted on the left and right ends of the guide roller, the adjacent third bevel gears are meshed with the second bevel gear, a limiting assembly is arranged in the n-shaped plate, a reset assembly is arranged on the limiting assembly, the reset assembly is respectively connected with the arc block and the hollow shell, and the clamping blocks on both sides and the arc blocks on both sides are brought close together to complete the limiting fixation of the sucker rod, so as to prevent the sucker rod from continuing to work when a blowout of crude oil occurs.

[0011] Furthermore, the front side of the clamping block is arranged in a backward concave shape, and the clamping block is used to clamp and limit the sucker rod.

[0012] Furthermore, the limit assembly includes a hollow frame, a hollow plate, a second rotating shaft, a mounting plate, a sliding block, a first wedge-shaped block, a fourth spring, a fixed frame and a thrust spring. Two hollow frames are installed at the rear of the conveying pipeline. Hollow plates are fixedly connected between the two hollow frames and the n-shaped plate respectively. The lower part of the hollow shell is rotatably installed with a second rotating shaft, and a mounting plate is installed on the second rotating shaft. A sliding block is fixedly connected to the upper part of the mounting plate. The sliding block is slidably matched with the adjacent hollow plate. A sliding groove extending backward is opened in the middle of the front side of the hollow frame. A first wedge block is provided in the slide groove for sliding, a fourth spring is fixedly connected between the first wedge block and the hollow frame, the fourth spring is located in the slide groove of the hollow frame, a slide groove extending forward is provided at the lower part of the rear side surface of the hollow plate, the front part of the first wedge block passes through the slide groove on the adjacent hollow plate and is slidably connected thereto, a wedge-shaped groove penetrating upward is provided at the middle part of the first wedge block, the upper parts of the inner sides of the hollow frames on the left and right sides are fixedly connected with fixed frames, and a thrust spring is fixedly connected between the front and rear adjacent fixed frames and the hollow shell body, and the thrust spring is used to push the hollow shell body to swing.

[0013] Furthermore, the reset assembly includes a transverse plate, a one-way gear, a first spur gear, a rack, a fifth spring, a sliding frame, a wedge plate, a support plate and a second wedge block. The lower outer side surfaces of the left and right fixing frames are both installed with transverse plates, the lower outer side surfaces of the left and right hollow shells are installed with one-way gears, the first spur gear is rotatably installed on the transverse plate, the adjacent one-way gears are meshed with the first spur gears, sliding grooves are provided on the left and right parts of the upper surface of the arc block, a rack is slidably provided in the sliding groove of the arc block, the rack is meshed with the adjacent first spur gear, a fifth spring is fixedly connected between the rack and the arc block, the fifth spring is located in the sliding groove of the arc block, The left and right parts are provided with grooves, and sliding frames are slidably arranged in the grooves of the left and right parts of the arc block. Two elastic protrusions are symmetrically arranged in the upper part of the sliding frame. The left and right parts of the arc block are installed with wedge plates, and the wedge plates on the left and right sides are respectively located in the grooves on the left and right sides of the arc block. A supporting plate is provided on the upper part of the wedge plate, and a second wedge block is fixedly connected to the upper side of the supporting plate. The upper and lower adjacent second wedge blocks and the wedge grooves on the first wedge block are slidably matched. Semicircular protrusions are arranged on the lower parts of the left and right walls of the sliding frame, and oblique grooves are provided on the inner walls of the grooves on the left and right sides of the arc block. The left and right protrusions on the sliding frame are respectively slidably arranged in the grooves on the left and right sides of the adjacent arc blocks.

[0014] Furthermore, the reset mechanism includes a third rotating shaft, a second spur gear, a fourth bevel gear, a fourth rotating shaft, a third spur gear and a rotating frame. The third rotating shaft is rotatably installed at the lower part of the fixed frame, the second spur gear is installed at one end of the third rotating shaft, and the fourth bevel gear is installed at the other end of the third rotating shaft. The fourth bevel gear is meshed with the adjacent first bevel gear. The front and rear parts of the conveying pipeline are rotatably installed with the fourth rotating shaft, the third spur gear is installed at one end of the fourth rotating shaft, the third spur gear is meshed with the adjacent second spur gear, and the rotating frame is installed at the other end of the fourth rotating shaft. The rotating frame is rotated to restore the device to its initial position and release the limit on the sucker rod.

[0015] Furthermore, a rubber ring is included. A rubber ring is installed on the upper and lower parts of the outer side of the sealing shell respectively. The rubber ring is arranged as an inclined surface from top to bottom. The rubber ring is sealed with the conveying pipeline. The rubber ring is used to improve the sealing between the sealing shell and the conveying pipeline to prevent the crude oil from moving upward through the gap between the sealing shell and the conveying pipeline during the upward flow, which will hinder the closure when the crude oil spraying amount is overloaded.

[0016] The beneficial effects are as follows: the present invention cooperates with the closing mechanism, the positioning mechanism and the resetting mechanism, and utilizes the fixed shell and the sealing shell to cooperate with the hollow sealing frames on the upper and lower sides respectively, to form a double-layer closure for the conveying pipeline, so as to avoid the conveying pipeline being unable to be closed when crude oil blows out, resulting in crude oil leakage; the clamping blocks on both sides and the arc blocks on both sides are brought close to each other to complete the limit fixation of the sucker rod, so as to avoid the sucker rod continuing to work when crude oil blows out; the rotating frame is rotated to restore the device to the initial position, and the limit on the sucker rod is released; the rubber ring is used to improve the sealing between the sealing shell and the conveying pipeline, so as to avoid the crude oil flowing upward through the gap between the sealing shell and the conveying pipeline during the upward flow, which will hinder the closure when the crude oil spraying amount is overloaded. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention.

[0018] Figure 2 It is a schematic diagram of the cross-sectional three-dimensional structure of the delivery pipeline of the present invention.

[0019] Figure 3 It is a schematic cross-sectional three-dimensional structural diagram of the sealing mechanism of the present invention.

[0020] Figure 4 It is a partially cutaway three-dimensional structural schematic diagram of the sealing mechanism of the present invention.

[0021] Figure 5 It is a partial three-dimensional structural schematic diagram of the sealing mechanism of the present invention.

[0022] Figure 6 It is a partial three-dimensional structural schematic diagram of the closing mechanism of the present invention.

[0023] Figure 7 It is a three-dimensional structural schematic diagram of the positioning mechanism of the present invention.

[0024] Figure 8 It is a schematic diagram of a first partially cutaway stereoscopic structure of the positioning mechanism of the present invention.

[0025] Fig. 9 It is a schematic diagram of a second partially cutaway stereoscopic structure of the positioning mechanism of the present invention.

[0026] Fig.10 It is a schematic diagram of the partial three-dimensional structure of the positioning mechanism of the present invention.

[0027] Fig.11 It is a partial three-dimensional structural schematic diagram of the positioning mechanism of the present invention.

[0028] Fig.12 It is a schematic diagram of the local three-dimensional structure of the present invention.

[0029] In the above drawings: 1, lower valve body, 2, delivery pipeline, 3, upper valve body, 4, sucker rod, 501, fixed shell, 502, guide rod, 503, sealing shell, 504, first spring, 505, hollow sealing frame, 506, disc, 507, fixed pipe, 508, inner shell, 509, connecting frame, 510, arc limit rod, 511, rotating plate, 512, torsion spring, 513, connecting plate, 514, L-shaped rod, 515, second spring, 601, arc block, 602, n-shaped plate, 603, sliding rod, 604, clamping block, 605, third spring, 606, screw, 607, worm gear, 608, mounting frame, 609, worm, 610, hollow shell, 611, first bevel gear, 612. The first rotating shaft; 613. The second bevel gear; 614. The guide roller; 615. The third bevel gear; 616. The hollow frame; 617. The hollow plate; 618. The second rotating shaft; 619. The mounting plate; 620. The sliding block; 621. The first wedge block; 622. The fourth spring; 623. The fixed frame; 624. The thrust spring; 625. The cross plate; 626. The one-way gear; 627. The first spur gear; 628. The rack; 629. The fifth spring; 630. The sliding frame; 631. The wedge plate; 632. The supporting plate; 633. The second wedge block; 7. The third rotating shaft; 8. The second spur gear; 9. The fourth bevel gear; 10. The fourth rotating shaft; 11. The third spur gear; 12. The rotating frame; 13. The rubber ring. DETAILED DESCRIPTION

[0030] The present invention will now be described more fully below with reference to the accompanying drawings, in which currently preferred embodiments of the present invention are shown. However, the present invention may be implemented in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided for thoroughness and completeness, and these embodiments fully convey the scope of the present invention to the skilled person.

[0031] Example 1

[0032] A wellhead Christmas tree with a flow rate overload shut-off function for an oil field production well, such as Figure 1 , Figure 2 and Figure 7As shown, it includes a lower valve body 1, a delivery pipeline 2, an upper valve body 3, a closing mechanism, a positioning mechanism and a reset mechanism. The delivery pipeline 2 is arranged on the upper part of the lower valve body 1, and the upper valve body 3 is arranged on the upper part of the delivery pipeline 2. Both sides of the upper valve body 3 and the lower valve body 1 are provided with flank oil pipelines. The lower valve body 1, the delivery pipeline 2, the upper valve body 3 and the flank oil pipelines cooperate to form an oil tree. The upper part of the delivery pipeline 2 is provided with a closing mechanism, which is used to double-close the delivery pipeline 2 to avoid the inability to close the delivery pipeline when the crude oil blows out. Pipe 2 causes crude oil leakage. Positioning mechanisms are provided on both sides of the front and rear of the middle of the pipeline 2. The positioning mechanisms are used to limit and fix the sucker rod 4 to prevent the sucker rod 4 from continuing to work when a blowout occurs. A filter is provided at the lower part of the pipeline 2. The filter is used to filter the crude oil. The sucker rod 4 passes through the filter and slides with the filter. The sucker rod 4 passes through the top of the upper valve body 3 and slides and seals with it. A reset mechanism is provided on the pipeline 2. The reset mechanism is used to reset the positioning mechanism and release the limit on the sucker rod 4.

[0033] like Figure 2-Figure 6As shown, the sealing mechanism includes a fixed shell 501, a guide rod 502, a sealing shell 503, a first spring 504, a hollow sealing frame 505, a disc 506, a fixed tube 507, an inner shell 508, a connecting frame 509, an arc-shaped limiting rod 510, a rotating plate 511, a torsion spring 512, a connecting plate 513, an L-shaped rod 514 and a second spring 515. The upper inner part of the conveying pipeline 2 is fixedly connected with the fixed shell 501, and the front and rear parts of the lower surface of the fixed shell 501 are both connected with the guide rod 502. The sealing shell 503 is slidably provided at the lower part of the guide rod 502 on the front and rear sides. Two first springs 504 are fixedly connected between the sealing shell 503 and the fixed shell 501. The first springs 504 on the front and rear sides are respectively sleeved on the outer sides of the guide rods 502 on the front and rear sides. The sealing shell 503 and The interior of the fixed shell 501 is slidably provided with a hollow sealing frame 505, the middle part of the hollow sealing frame 505 is a cavity setting, the upper surface of the hollow sealing frame 505 is circumferentially provided with four circular holes penetrating downward, the cavity of the hollow sealing frame 505 is connected with the circular holes, the outer side of the hollow sealing frame 505 is provided with a plurality of triangular blocks, the upper inner part of the fixed shell 501 and the sealing shell 503 are provided with a plurality of triangular blocks, the fixed shell 501 and the sealing shell 503 are respectively slidably sealed with the hollow sealing frames 505 on the upper and lower sides, and the fixed shell 501 and the sealing shell 503 are respectively matched with the hollow sealing frames 505 on both sides, so that the delivery pipeline 2 is double-sealed to avoid the inability to close the delivery pipeline 2 when the crude oil blows out, resulting in crude oil leakage, and the hollow sealing A disc 506 is slidably arranged in the cavity of the frame 505, and four discharge holes are circumferentially arranged on the upper surface of the disc 506 and penetrate downward. The discharge holes on the disc 506 have the same diameter as the circular holes on the hollow sealing frame 505. A fixed pipe 507 is fixedly connected between the inner side surfaces of the upper and lower adjacent hollow sealing frames 505. An inner shell 508 is slidably arranged in the fixed pipe 507. The upper and lower parts of the inner shell 508 are respectively slidably connected with the hollow sealing frames 505 passing through the upper and lower sides, and the upper and lower parts of the inner shell 508 are respectively fixedly connected with the discs 506 on the upper and lower sides. When the flow rate of crude oil is overloaded, the inner shell 508 moves upward and rotates at the same time, thereby driving the disc 506 to rotate 45 degrees, so that the hollow sealing frame 505 and the disc 506 cooperate to complete the hollow sealing frame 505. The sealing frame 505 is closed to prevent the delivery pipeline 2 from being unable to be closed when the crude oil flow rate is overloaded, resulting in crude oil leakage. A connecting frame 509 is installed on the lower surface of the inner shell 508. Arc-shaped limit rods 510 are installed on the front and rear sides of the lower part of the connecting frame 509. The sucker rod 4 passes through the upper hollow sealing frame 505, the disc 506, the inner shell 508, the lower hollow sealing frame 505 and the connecting frame 509 and is slidingly sealed therewith. The front and rear sides of the upper inner part of the sealing shell 503 are rotatably installed with a rotating plate 511 through a rotating rod. The rotating rods on the left and right sides of the rotating plate 511 are sleeved with torsion springs 512. The two ends of the torsion spring 512 are respectively fixed to the sealing shell 503 and the rotating plate 511. Two connecting plates 513 are installed on the front and rear parts of the sealing shell 503.An L-shaped rod 514 is slidably arranged between the upper and lower adjacent connecting plates 513. The lower side of the fixed tube 507 is provided with a sliding groove extending upward at both the front and rear parts. The L-shaped rods 514 at the front and rear sides respectively pass through the sliding grooves at the front and rear sides of the fixed tube 507 and slide with it. Two second springs 515 are fixedly connected to the upper part of the L-shaped rod 514. The upper and lower adjacent second springs 515 are fixedly connected to the connecting plate 513. The lower side of the front and rear parts of the inner shell 508 is provided with an oblique groove. The L-shaped rods 514 at the front and rear sides respectively slide with the oblique grooves at the front and rear sides of the inner shell 508.

[0034] like Figure 7-Figure 11As shown, the positioning mechanism includes an arc block 601, an n-shaped plate 602, a slide bar 603, a clamping block 604, a third spring 605, a screw 606, a worm gear 607, a mounting frame 608, a worm 609, a hollow housing 610, a first bevel gear 611, a first rotating shaft 612, a second bevel gear 613, a guide roller 614, a third bevel gear 615, a hollow frame 616, a hollow plate 617, a second rotating shaft 618, a mounting plate 619, a sliding block 620, a first wedge block 621, a fourth spring 622, a fixing frame 623, a thrust spring 624, a transverse plate 625, a one-way gear 626, a first straight gear 627, a rack 628, a fifth spring 629, a sliding frame 630, a wedge plate 631, a support plate 632 and a second Wedge block 633, an arc block 601 is slidably provided on the rear side of the middle part of the conveying pipeline 2, and an arc groove extending backward is provided on the front side of the arc block 601, which is used to clamp and limit the sucker rod 4. An n-shaped plate 602 is installed on the upper surface of the arc block 601, and a sliding rod 603 is slidably provided on the upper surface of the n-shaped plate 602. A clamping block 604 is fixedly connected to the upper end of the sliding rod 603, and the front side of the clamping block 604 is set in a backward concave shape. The clamping block 604 is used to clamp and limit the sucker rod 4. The front and rear clamping blocks 604 on both sides cooperate to increase the limit of the sucker rod 4 and slow down the moving speed of the sucker rod 4. The arc blocks 601 on the front and rear sides are close to each other to fix the sucker rod 4, so as to avoid inconvenience caused by the sucker rod 4 continuing to work after the conveying pipeline 2 is closed. The clamping block A third spring 605 is fixedly connected between 604 and the n-shaped plate 602, and the third spring 605 is sleeved on the outer side of the slide rod 603. A rectangular groove is downwardly opened in the middle of the upper surface of the arc block 601, and a screw rod 606 is rotatably installed in the middle of the arc block 601. The screw rod 606 is located in the rectangular groove of the arc block 601. A worm gear 607 is threadedly connected to the screw rod 606. A mounting frame 608 is arranged at the rear of the worm gear 607. A worm 609 is rotatably installed on the upper part of the mounting frame 608. The worm 609 and the worm gear 607 are meshed. A hollow shell 610 is rotatably installed on the left and right walls of the mounting frame 608. The left and right parts of the worm 609 are both equipped with a first bevel gear 611. A first rotating shaft 612 is rotatably installed in the hollow shell 610. The first rotating shaft 61 2 is provided with second bevel gears 613 at both upper and lower ends, the adjacent second bevel gears 613 are meshed with the first bevel gears 611, guide rollers 614 are rotatably installed between the left and right adjacent hollow shells 610, third bevel gears 615 are installed at both left and right ends of the guide rollers 614, the adjacent third bevel gears 615 are meshed with the second bevel gears 613, two hollow frames 616 are installed at the rear of the conveying pipeline 2, hollow plates 617 are fixedly connected between the two hollow frames 616 and the n-shaped plate 602, a second rotating shaft 618 is rotatably installed at the lower part of the hollow shell 610, a mounting plate 619 is installed on the second rotating shaft 618, a sliding block 620 is fixedly connected to the upper part of the mounting plate 619, and the sliding block 620 is slidably matched with the adjacent hollow plate 617,A sliding groove extending backward is provided in the middle of the front side of the hollow frame 616, and a first wedge block 621 is slidably provided in the sliding groove of the hollow frame 616. A fourth spring 622 is fixedly connected between the first wedge block 621 and the hollow frame 616, and the fourth spring 622 is located in the sliding groove of the hollow frame 616. A sliding groove extending forward is provided at the lower part of the rear side of the hollow plate 617, and the front part of the first wedge block 621 passes through the sliding groove on the adjacent hollow plate 617 and is slidably connected thereto. A wedge groove penetrating upward is provided in the middle of the first wedge block 621, and the hollow frames 617 on the left and right sides are provided with a plurality of sliding grooves extending forward. The upper part of the inner side surface of the arc block 601 is fixedly connected with a fixing frame 623, and a thrust spring 624 is fixedly connected between the front and rear adjacent fixing frames 623 and the hollow shell 610. The thrust spring 624 is used to push the hollow shell 610 to swing. The lower part of the outer side surface of the fixing frames 623 on the left and right sides is installed with a horizontal plate 625, and the lower part of the outer side surface of the hollow shell 610 on the left and right sides is installed with a one-way gear 626. The first straight gear 627 is rotatably installed on the horizontal plate 625, and the adjacent one-way gear 626 is meshed with the first straight gear 627. The left and right parts of the upper surface of the arc block 601 are A sliding groove is provided in each of the arc block 601, a rack 628 is slidably provided in the sliding groove of the arc block 601, the rack 628 is meshed with the adjacent first spur gear 627, a fifth spring 629 is fixedly connected between the rack 628 and the arc block 601, the fifth spring 629 is located in the sliding groove of the arc block 601, a groove is provided in the left and right parts of the arc block 601, a sliding frame 630 is slidably provided in the grooves of the left and right parts of the arc block 601, two elastic protrusions are symmetrically provided in the upper part of the sliding frame 630, a wedge plate 631 is installed in the left and right parts of the arc block 601, the left The wedge plates 631 on the right side are respectively located in the grooves on the left and right sides of the arc block 601. A support plate 632 is provided on the upper part of the wedge plate 631. A second wedge block 633 is fixedly connected to the upper side of the support plate 632. The second wedge blocks 633 and the wedge grooves on the first wedge block 621, which are adjacent to each other, are slidably matched. The lower parts of the left and right walls of the sliding frame 630 are both provided with semicircular protrusions. The inner walls of the grooves on the left and right sides of the arc block 601 are both provided with oblique grooves. The left and right protrusions on the sliding frame 630 are respectively slidably located in the grooves on the left and right sides of the adjacent arc block 601.

[0035] like Figure 7 and Fig.12 As shown, the reset mechanism includes a third rotating shaft 7, a second spur gear 8, a fourth bevel gear 9, a fourth rotating shaft 10, a third spur gear 11 and a rotating frame 12. The third rotating shaft 7 is rotatably installed on the lower part of the fixed frame 623, one end of the third rotating shaft 7 is installed with the second spur gear 8, the other end of the third rotating shaft 7 is installed with the fourth bevel gear 9, the fourth bevel gear 9 is meshed with the adjacent first bevel gear 611, the front and rear parts of the conveying pipeline 2 are rotatably installed with the fourth rotating shaft 10, one end of the fourth rotating shaft 10 is installed with the third spur gear 11, the third spur gear 11 is meshed with the adjacent second spur gear 8, and the other end of the fourth rotating shaft 10 is installed with the rotating frame 12.

[0036] When in use, the user installs the external oil spray nozzle on the side oil pipeline on the right side of the upper valve body 3, and forms an oil tree through the cooperation of the lower valve body 1, the delivery pipeline 2 and the upper valve body 3. As the sucker rod 4 moves up and down, the mined crude oil is pumped upward, and the crude oil flows through the lower valve body 1, the delivery pipeline 2 and the upper valve body 3, and is sprayed out through the side oil pipeline on the right side of the upper valve body 3 through the external oil spray nozzle. The crude oil has a certain impact force during the upward flow, and the impact force of the crude oil changes with the change of the spraying amount of the crude oil.

[0037] When the upward spraying amount of crude oil is small, the elastic force of the second spring 515 on the upper and lower sides limits the L-shaped rod 514 and the inner shell 508, so that the hollow sealing frame 505 on the lower side resists the upward moving impulse of the crude oil to prevent the impact force of the upward flow of crude oil from pushing the hollow sealing frame 505 on the lower side to move upward. When the upward spraying amount of crude oil is large, the impact force of the crude oil flow in the conveying pipe increases accordingly. The increase in the impact force of the upward flow of crude oil will impact the sealing shell 503 to move upward, and the first spring 504 will be compressed accordingly. The sealing shell 503 moves upward to drive the rotating plate 511, the torsion spring 512, the connecting plate 513, the second spring 515 and the L-shaped rod 514 to move upward. The rotating plate 511 moves upward to cooperate with the guide rod 502. At this time, the outer parts of the rotating plates 511 on both sides swing downward accordingly, and the inner parts of the rotating plates 511 on both sides swing upward. At the same time, the L-shaped rod 514 moves upward to cooperate with the inclined groove on the inner shell 508, so that the inner shell 508 rotates 45 The inner shell 508 rotates 45 degrees to make the disc 506 rotate 45 degrees. At this time, the disc 506 closes the hollow sealing frame 505. The inner shell 508 moves upward while rotating. The inner shell 508 moves upward to drive the disc 506 to move upward. The disc 506 moves upward to drive the hollow sealing frame 505 to move upward. The upper hollow sealing frame 505 moves upward to cooperate with the fixed shell 501 to close the fixed shell 501. At this time, the position of the lower hollow sealing frame 505 is limited accordingly. The sealing shell 503 moves upward and cooperates with the hollow sealing frame 505 on the lower side to complete the sealing of the sealing shell 503, thereby realizing double-layer sealing of the conveying pipeline 2, and completing the sealing of the conveying pipeline 2 when the crude oil blows out, thereby realizing closing when the crude oil flow rate is overloaded. When the flow rate of the crude oil is restored, the sealing shell 503 moves downward and resets under the action of the first spring 504, so that the disc 506 rotates and resets, and the hollow sealing frame 505 is opened at this time, and the crude oil continues to flow upward.

[0038] The disc 506 rotates 45 degrees through the connecting frame 509 to rotate the arc-shaped limiting rod 510 45 degrees, thereby releasing the limiting of the guide roller 614. At this time, the hollow shells 610 on the front and rear sides are respectively swung inwards under the action of the thrust springs 624 on the front and rear sides. The inward swinging of the hollow shells 610 on the front and rear sides drives the one-way gears 626 on the front and rear sides to rotate. At this time, the rotation of the one-way gear 626 does not provide power for the rotation of the first straight gear 627. The inward swinging of the hollow shells 610 on the front and rear sides drives the second rotating shafts 618 on the front and rear sides to swing inwards. The inward swinging of the second rotating shafts 618 on the front and rear sides drives the mounting plates 619 on the front and rear sides to swing inwards. At this time, through the cooperation of the sliding block 620 and the hollow plate 617, as shown in FIG. This causes the sliding block 620 to move downward, and the sliding block 620 moves downward to squeeze the first wedge block 621, and the fourth spring 622 is compressed accordingly, so that the first wedge block 621 is away from the hollow plate 617. At this time, the limit of the lower part of the hollow plate 617 is released, and the sliding block 620 continues to move downward. When the sliding block 620 moves downward and away from the first wedge block 621, the first wedge block 621 is reset under the action of the fourth spring 622. At this time, the limit of the sliding block 620 is completed, and the limit of the guide roller 614 is completed. At this time, the guide roller 614 is in contact with the sucker rod 4. At this time, the sucker rod 4 moves upward, and the upward movement of the sucker rod 4 drives the guide roller 614 to rotate, and the rotation of the guide roller 614 drives the third bevel gear 615 to rotate. The rotation of the wheel 615 drives the adjacent second bevel gear 613 to rotate, so that the first rotating shaft 612 rotates, the first rotating shaft 612 rotates through the corresponding third bevel gear 615 to rotate the first bevel gear 611, the first bevel gear 611 rotates to drive the worm 609 to rotate, the worm 609 rotates to drive the worm wheel 607 to rotate, the worm wheel 607 rotates and cooperates with the screw rod 606, so that the screw rods 606 on the front and rear sides are brought together, the screw rods 606 on the front and rear sides are brought together to drive the arc blocks 601 on the front and rear sides to move together, the arc blocks 601 on the front and rear sides are brought together to drive the n-shaped plates 602 on the front and rear sides to move together, the n-shaped plates 602 on the front and rear sides are brought together to drive the sliding rods 603 on the front and rear sides to move together, and the sliding rods 603 on the front and rear sides are brought together to make the front and rear The clamping blocks 604 on both sides are close to each other, and the clamping blocks 604 on the front and rear sides are close to each other and contact the sucker rod 4, thereby increasing the friction force of the sucker rod 4 moving upward, thereby slowing down the speed of the sucker rod 4 moving upward. At the same time, the arc blocks 601 on both sides continue to move closer to each other. When the arc blocks 601 on both sides move closer to each other and contact the sucker rod 4, the friction force with the sucker rod 4 is further increased. At this time, the arc blocks 601 on both sides and the clamping blocks 604 on both sides move closer to each other to complete the limiting fixation of the sucker rod 4. The arc blocks 601 on both sides move closer to drive the components thereon to move closer, thereby making the sliding frames 630 on both sides move closer to each other, and the sliding frames 630 on both sides move closer to cooperate with the support plates 632 on both sides to complete the limiting of the support plates 632 on both sides.

[0039] When it is necessary to release the fixation of the sucker rod 4, the user rotates the rotating frames 12 on the front and rear sides respectively, and the rotating frames 12 on the front and rear sides respectively drive the fourth shaft 10 to rotate, and the rotation of the fourth shaft 10 drives the third spur gear 11 to rotate, and the rotation of the third spur gear 11 drives the adjacent second spur gear 8 to rotate, and the rotation of the second spur gear 8 drives the third shaft 7 to rotate, and the rotation of the third shaft 7 drives the fourth bevel gear 9 to rotate, and the rotation of the fourth bevel gear 9 causes the adjacent first bevel gear 611 to rotate, and the rotation of the first bevel gear 611 drives the worm 609 to rotate, and the rotation of the worm 609 drives the worm wheel 607 to rotate, and the rotation of the worm wheels 607 on both sides respectively causes the screw rods 606 on both sides to move away from each other, so that the arc blocks 601 on both sides move away from each other, and the arc blocks 601 on both sides move away from each other respectively drive the components thereon to move away, so that the racks 628 on both sides move away, and the racks 628 on both sides move away to cause the first spur gear 627 to rotate, and the rotation of the first spur gear 627 drives the adjacent one-way gear The wheel 626 rotates, and the one-way gear 626 rotates to drive the hollow shell 610 to rotate and reset, so that the guide roller 614 is away from the sucker rod 4, and the thrust spring 624 is compressed accordingly. At the same time, the arc limit rod 510 rotates and resets to support the guide roller 614, and the arc blocks 601 on both sides are separated from each other and the wedge plates 631 on both sides are driven to separate from each other. Since two elastic protrusions are provided on the upper part of the sliding frame 630, the wedge plates 631 on both sides are separated from each other, and the sliding frames 630 on both sides are pushed to move upward along the inclined grooves on the arc blocks 601. The sliding frames 630 on both sides move upward and drive the support plates 632 and the second wedge blocks 633 on both sides to move upward. The second wedge blocks 633 move upward and push the first wedge blocks 621 away from the hollow plate 617, so that the limit of the sliding block 620 is released. At this time, the sliding block 620 moves upward and resets accordingly, and the support plates 632 are reset and away from the sliding frame 630 at this time. At the same time, the sliding frame 630 is reset under the action of gravity.

[0040] Example 2

[0041] On the basis of Example 1, Figure 3 As shown, a rubber ring 13 is also included. A rubber ring 13 is installed on the upper and lower parts of the outer side surface of the sealing shell 503 respectively. The rubber ring 13 is set as an inclined surface from top to bottom. The rubber ring 13 is sealed with the conveying pipeline 2. The rubber ring 13 improves the sealing performance between the sealing shell 503 and the conveying pipeline 2 to prevent the crude oil from flowing upward through the gap between the sealing shell 503 and the conveying pipeline 2 during the upward flow of the crude oil, which will hinder the closure when the crude oil spraying amount is overloaded. When the rubber ring 13 moves downward, the crude oil on the inner wall of the conveying pipeline 2 is scraped off. Since the rubber ring 13 is set as an inclined surface from top to bottom, it is convenient for the scraped crude oil to slide downward, thereby preventing the crude oil from sticking to the inner wall of the conveying pipeline 2.

[0042] While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments.The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.

Claims

1. A wellhead Christmas tree for an oil field production well with a flow rate overload shutoff function, comprising a lower valve body (1), a delivery pipeline (2) and an upper valve body (3), wherein the delivery pipeline (2) is arranged on the upper part of the lower valve body (1), the upper valve body (3) is arranged on the upper part of the delivery pipeline (2), and flank oil pipelines are arranged on both sides of the upper valve body (3) and the lower valve body (1), and the lower valve body (1), the delivery pipeline (2), the upper valve body (3) and the flank oil pipelines cooperate to form the Christmas tree, wherein: It also includes a closing mechanism, a positioning mechanism and a reset mechanism. The upper part of the delivery pipeline (2) is provided with a closing mechanism, which is used to seal the delivery pipeline (2). Positioning mechanisms are provided on both the front and rear sides of the middle part of the delivery pipeline (2). The positioning mechanisms are used to limit and fix the sucker rod (4). The lower part of the delivery pipeline (2) is provided with a filter screen, which is used to filter crude oil. The sucker rod (4) passes through the filter screen and slides with it. The sucker rod (4) passes through the top of the upper valve body (3) and slides and seals with it. The delivery pipeline (2) is provided with a reset mechanism, which is used to release the fixed limit of the sucker rod (4). The sealing mechanism comprises a fixed shell (501), a guide rod (502), a sealing shell (503), a first spring (504), a hollow sealing frame (505), a disc (506), a fixed tube (507), an inner shell (508), a connecting frame (509), an arc-shaped limiting rod (510) and a sealing assembly. The fixed shell (501) is fixedly connected to the upper inner portion of the conveying pipeline (2). The front and rear portions of the lower surface of the fixed shell (501) are both connected to the guide rod (502). The sealing shell (503) is slidably provided at the lower portions of the guide rods (502) on the front and rear sides. Two first springs (504) are fixedly connected between the sealing shell (503) and the fixed shell (501). The first springs (504) on the front and rear sides are respectively sleeved on the outside of the guide rods (502) on the front and rear sides. A hollow sealing frame (505) is slidably provided inside the sealing shell (503) and the fixed shell (501). The middle part of the hollow sealing frame (505) is provided with a cavity. Four circular holes penetrating downward are opened in the circumferential direction on the upper surface of the hollow sealing frame (505). The cavity of the hollow sealing frame (505) is connected to the circular holes. A disc (506) is provided for sliding inside, and four discharge holes are provided on the upper surface of the disc (506) in a circumferential direction and penetrate downward. The discharge holes on the disc (506) have the same diameter as the circular holes on the hollow sealing frame (505). A fixed tube (507) is fixedly connected between the inner side surfaces of the upper and lower adjacent hollow sealing frames (505). An inner shell (508) is provided for sliding inside the fixed tube (507). The upper and lower parts of the inner shell (508) are respectively connected to the hollow sealing frames (505) passing through the upper and lower sides thereof for sliding connection. The upper and lower parts of the inner shell (508) are respectively connected to the upper and lower sides thereof for sliding connection. The discs (506) on the lower two sides are fixedly connected, a connecting frame (509) is installed on the lower surface of the inner shell (508), arc-shaped limit rods (510) are installed on the front and rear sides of the lower part of the connecting frame (509), a sealing assembly is arranged on the upper part of the sealing shell (503), and the sealing assembly passes through the fixed tube (507) and cooperates with the inner shell (508), and the sucker rod (4) passes through the upper hollow sealing frame (505), the disc (506), the inner shell (508), the lower hollow sealing frame (505) and the connecting frame (509), and is arranged to slide and seal with them.

2. A wellhead Christmas tree with a flow rate overload shutdown function for an oil field production well according to claim 1, characterized in that: The outer side surface of the hollow sealing frame (505) is provided with a plurality of triangular blocks, and the inner upper parts of the fixed shell (501) and the sealing shell (503) are both provided with a plurality of triangular blocks. The fixed shell (501) and the sealing shell (503) are respectively slidably sealed with the hollow sealing frame (505) at the upper and lower sides.

3. A wellhead Christmas tree with a flow rate overload shutdown function for an oil field production well according to claim 1, characterized in that: The sealing assembly comprises a rotating plate (511), a torsion spring (512), a connecting plate (513), an L-shaped rod (514) and a second spring (515). The rotating plates (511) are rotatably mounted on both the front and rear sides of the upper inner portion of the sealing shell (503) via rotating rods. The rotating rods on the left and right sides of the rotating plate (511) are sleeved with torsion springs (512). The two ends of the torsion springs (512) are respectively fixedly connected to the sealing shell (503) and the rotating plate (511). The front and rear parts of the sealing shell (503) are both equipped with two connecting plates (513). The upper and lower adjacent connecting plates (513) are connected to each other. An L-shaped rod (514) is slidably arranged between the inner shell (508), the front and rear parts of the lower side surface of the fixed tube (507) are provided with upwardly extending sliding grooves, the front and rear L-shaped rods (514) respectively pass through the front and rear sliding grooves of the fixed tube (507) to slide with it, the upper part of the L-shaped rod (514) is fixedly connected to two second springs (515), the upper and lower adjacent second springs (515) are fixedly connected to the connecting plate (513), the front and rear parts of the inner shell (508) are provided with oblique grooves on the lower sides, and the front and rear L-shaped rods (514) respectively slide with the front and rear oblique grooves of the inner shell (508).

4. A wellhead Christmas tree with a flow rate overload shutdown function for an oil field production well according to claim 1, characterized in that: The positioning mechanism comprises an arc block (601), an n-shaped plate (602), a sliding rod (603), a clamping block (604), a third spring (605), a screw rod (606), a worm wheel (607), a mounting frame (608), a worm (609), a hollow housing (610), a first bevel gear (611), a first rotating shaft (612), a second bevel gear (613), a guide roller (614), a third bevel gear (615), a limit assembly and a reset assembly. The arc block (601) is slidably provided on the rear side of the middle part of the conveying pipeline (2). The front side of the arc block (601) is provided with An arc groove extending backwards is provided for clamping and limiting the sucker rod (4); an n-shaped plate (602) is installed on the upper surface of the arc block (601); a slide bar (603) is slidably provided on the upper surface of the n-shaped plate (602); a clamping block (604) is fixedly connected to the upper end of the slide bar (603); a third spring (605) is fixedly connected between the clamping block (604) and the n-shaped plate (602); the third spring (605) is sleeved on the outer side of the slide bar (603); a rectangular groove is opened downwards in the middle of the upper surface of the arc block (601); a screw rod (606) is rotatably installed in the middle of the arc block (601); The rod (606) is located in the rectangular groove of the arc block (601), the screw rod (606) is threadedly connected with a worm wheel (607), a mounting frame (608) is arranged at the rear of the worm wheel (607), a worm (609) is rotatably mounted on the upper part of the mounting frame (608), the worm (609) and the worm wheel (607) are meshed, a hollow housing (610) is rotatably mounted on the left and right walls of the mounting frame (608), a first bevel gear (611) is mounted on the left and right parts of the worm (609), a first rotating shaft (612) is rotatably mounted in the hollow housing (610), and the first rotating shaft (612) is rotatably mounted in the hollow housing (610). A second bevel gear (613) is installed at both upper and lower ends of the arc block (601), and the adjacent second bevel gears (613) are meshed with the first bevel gear (611). A guide roller (614) is rotatably installed between the left and right adjacent hollow shells (610). A third bevel gear (615) is installed at both left and right ends of the guide roller (614), and the adjacent third bevel gears (615) are meshed with the second bevel gear (613). A limit assembly is arranged in the n-shaped plate (602), and a reset assembly is arranged on the limit assembly. The reset assembly is respectively connected to the arc block (601) and the hollow shell (610).

5. A wellhead Christmas tree with a flow rate overload shut-off function for an oil field production well according to claim 4, characterized in that: The front side surface of the clamping block (604) is arranged in a backward concave shape, and the clamping block (604) is used to clamp and limit the position of the sucker rod (4).

6. A wellhead Christmas tree with a flow rate overload shut-off function for an oil field production well according to claim 4, characterized in that: The limiting assembly comprises a hollow frame (616), a hollow plate (617), a second rotating shaft (618), a mounting plate (619), a sliding block (620), a first wedge block (621), a fourth spring (622), a fixing frame (623) and a thrust spring (624). Two hollow frames (616) are installed at the rear of the conveying pipe (2). Hollow plates (617) are respectively fixedly connected between the two hollow frames (616) and the n-shaped plate (602). The lower part of the hollow shell (610) is rotatably mounted with a second rotating shaft (618). The mounting plate (619) is mounted on the second rotating shaft (618). The upper part of the mounting plate (619) is fixedly connected with a sliding block (620). The sliding block (620) is slidably matched with the adjacent hollow plate (617). A rearwardly extending groove is provided in the middle of the front side surface of the hollow frame (616). A first wedge block (621) is slidably provided in the slide groove of the hollow frame (616), a fourth spring (622) is fixedly connected between the first wedge block (621) and the hollow frame (616), and the fourth spring (622) is located in the slide groove of the hollow frame (616). A slide groove extending forward is provided at the lower part of the rear side surface of the hollow plate (617), the front part of the first wedge block (621) passes through the slide groove on the adjacent hollow plate (617) and is slidably connected thereto, a wedge groove penetrating upward is provided in the middle part of the first wedge block (621), the upper parts of the inner sides of the hollow frames (616) on the left and right sides are fixedly connected with fixing frames (623), and thrust springs (624) are fixedly connected between the front and rear adjacent fixing frames (623) and the hollow shell (610), and the thrust springs (624) are used to push the hollow shell (610) to swing.

7. A wellhead Christmas tree with a flow rate overload shut-off function for an oil field production well according to claim 4, characterized in that: The reset assembly comprises a transverse plate (625), a one-way gear (626), a first straight gear (627), a rack (628), a fifth spring (629), a sliding frame (630), a wedge plate (631), a support plate (632) and a second wedge block (633). The lower portions of the outer side surfaces of the fixing frames (623) on the left and right sides are both provided with transverse plates (625). The lower portions of the outer side surfaces of the hollow housings (610) on the left and right sides are provided with one-way gears (626). The transverse plates (62 5) A first spur gear (627) is rotatably mounted on the upper surface, and an adjacent one-way gear (626) meshes with the first spur gear (627). Sliding grooves are provided on both left and right parts of the upper surface of the arc block (601). A rack (628) is slidably provided in the sliding groove of the arc block (601). The rack (628) meshes with the adjacent first spur gear (627). A fifth spring (629) is fixedly connected between the rack (628) and the arc block (601). The fifth spring (629) Located in the sliding groove of the arc block (601), the left and right parts of the arc block (601) are both provided with grooves, the grooves of the left and right parts of the arc block (601) are both slidably provided with sliding racks (630), the upper part of the sliding rack (630) is symmetrically provided with two elastic protrusions, the left and right parts of the arc block (601) are both installed with wedge plates (631), the wedge plates (631) on the left and right sides are respectively located in the grooves on the left and right sides of the arc block (601), and the upper part of the wedge plates (631) is provided with A support plate (632) is fixedly connected to the upper side of the support plate (632) with a second wedge block (633). The upper and lower adjacent second wedge blocks (633) and the wedge grooves on the first wedge block (621) are slidably matched. The lower parts of the left and right walls of the sliding frame (630) are both provided with semicircular protrusions. The inner walls of the left and right grooves of the arc block (601) are both provided with oblique grooves. The left and right protrusions on the sliding frame (630) are respectively slidably located in the left and right grooves on the adjacent arc blocks (601).

8. A wellhead Christmas tree with a flow rate overload shut-off function for an oil field production well according to claim 1, characterized in that: The reset mechanism comprises a third rotating shaft (7), a second spur gear (8), a fourth bevel gear (9), a fourth rotating shaft (10), a third spur gear (11) and a rotating frame (12); the third rotating shaft (7) is rotatably mounted on the lower part of the fixed frame (623); one end of the third rotating shaft (7) is mounted with the second spur gear (8); the other end of the third rotating shaft (7) is mounted with the fourth bevel gear (9); the fourth bevel gear (9) meshes with the adjacent first bevel gear (611); the front and rear parts of the conveying pipeline (2) are both rotatably mounted with the fourth rotating shaft (10); one end of the fourth rotating shaft (10) is mounted with the third spur gear (11); the third spur gear (11) meshes with the adjacent second spur gear (8); the other end of the fourth rotating shaft (10) is mounted with the rotating frame (12).

9. A wellhead Christmas tree with a flow rate overload shut-off function for an oil field production well according to claim 1, characterized in that: It also includes a rubber ring (13). A rubber ring (13) is installed on the upper and lower parts of the outer side surface of the sealing shell (503). The rubber ring (13) is arranged as an inclined surface from top to bottom. The rubber ring (13) is in sealing cooperation with the conveying pipe (2).

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