Injection-production integrated pump hanging blowout preventer

Abstract

The present application belongs to the technical field of petroleum engineering, and particularly relates to a kind of injection-production integrated pump hanging wellhead blowout preventer, which is mainly composed of shell assembly, upper gate plate assembly, lower gate plate assembly, gate plate shaft assembly and stopper. The upper blowout preventer and the lower blowout preventer are used to control the well kick and blowout operation of the polished rod and the wellhead sucker rod respectively. The wrench square diameter is matched with the wrench to rotate the integral gate plate shaft. According to the spiral pair between the trapezoidal transmission inner thread of the gate plate shaft seat and the trapezoidal transmission outer thread of the integral gate plate shaft, the inner three-plane rotary pair between the multi-ring thrust bearing and the lower gate plate, and the four moving pairs of double-plane and double-cylinder surface combination between the lower gate plate and the blowout preventer shell, the gate plate shaft assembly transmits motion and power through the integral gate plate shaft, and the multi-ring thrust bearing pushes the upper gate plate assembly and the lower gate plate assembly to slide along the double-layer gate plate hole of the blowout preventer shell. The method Lan and the stop ring are used to realize the axial bidirectional limiting of the upper gate plate assembly and the lower gate plate assembly.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of petroleum engineering, and particularly relates to a wellhead blowout preventer for injection-production integrated pump hanging and pumping, in particular to a wellhead double-control blowout preventer for injection-production integrated pump hanging and pumping of heavy oil. BACKGROUND

[0002] The injection-production integrated technology and matching process for heavy oil thermal recovery huff and puff wells can realize one-time pipe column steam injection-oil pumping-steam injection circulation production. At present, the heavy oil thermal recovery huff and puff wells using injection-production integration carry out blowout and other processes after steam soaking, and then the oil pumping rod in the pipe column is hung by a crane and the integrated pump is grasped and connected, so as to finally realize the continuous production of steam injection and oil production without moving the pipe column. Field operation shows that how to control the overflow and well kick during the injection-production integrated pump hanging and pumping process is an effective means to shorten the injection-production integrated pump hanging and pumping time. During the injection-production integrated pump hanging and pumping process, the oil pumping rod is lifted and lowered, and the piston is grasped, and these processes are constructed without effective control tools, and in a non-controllable state throughout, and once well overflow or well kick occurs, it will be uncontrollable.

[0003] Therefore, by developing a wellhead blowout and overflow control device for heavy oil thermal recovery huff and puff wells, the overflow oil well hanging and pumping period can be shortened, and the well control failure time can be reduced. The research status analysis shows that there is little research on blowout preventers for injection-production integrated pump hanging and pumping, and the blowout preventers that have appeared are mainly used for drilling or workover operations.

[0004] The conventional workover operation is directly operated at the wellhead, and does not need a drilling platform. The workover operation needs to lift and pull out the oil pumping rod column and the oil pipe column, and the slips of the blowout preventer for workover operation need to be alternately opened and closed to pass through the oil pipe coupling. Usually, the rubber core is severely worn, and at the same time, the blowout preventer for workover operation not only needs to be suitable for blowout of the oil pipe and the casing annulus, but also needs to be suitable for controlling well kick of the liquid in the oil pipe.

[0005] During the injection-production integrated pump hanging and pumping, only the oil pumping rod column is lifted, and the oil pipe column is not moved. The injection-production integrated pump hanging and pumping operation requires to shorten the wellhead opening time as much as possible and reduce the non-controllable time. At the same time, the blowout preventer for injection-production integrated pump hanging and pumping only needs to clamp the oil pumping rod and the polished rod at the wellhead and prevent the well blowout and well kick in the oil pipe, and requires a compact structure, a small quality and convenient transportation. Therefore, it is necessary to design a blowout preventer for heavy oil thermal recovery huff and puff wells to solve the problems of well kick and well blowout during the injection-production integrated pump hanging and pumping operation. SUMMARY

[0006] The purpose of the present application is to overcome the shortcomings of the prior art, and to design an injection-production integrated pump hanging extraction wellhead blowout preventer, which adopts upper and middle sealing rubber cores, Y-shaped sealing rings and side door sealing rings to form non-metallic sealing, and effectively solves the problems of well kick and blowout during the hanging extraction operation of the heavy oil thermal recovery huff and puff well through the synergistic effect of the upper gate plate assembly, the lower gate plate assembly and the gate plate shaft assembly.

[0007] The technical scheme adopted by the present application to solve its technical problems is:

[0008] An injection-production integrated pump hanging extraction wellhead blowout preventer, comprising a housing assembly, an upper blowout preventer and a lower blowout preventer, wherein,

[0009] The injection-production integrated pump hanging extraction wellhead blowout preventer is connected with the wellhead packing box through the upper and lower tubing joints and coupling heads arranged on the housing assembly, and is integrated with the wellhead tee joint.

[0010] The upper blowout preventer is used to control the well kick and blowout operation of the polished rod, and comprises two sets of upper gate plate assemblies, two sets of gate plate shaft assemblies and two sets of limiters; each set of upper gate plate assembly is provided with one set of gate plate shaft assembly and one set of limiter; each set of gate plate shaft assembly is coaxially arranged with the corresponding limiter along the radial direction from inside to outside; the center line of the upper gate plate assembly is coincident with the axis of the gate plate shaft assembly.

[0011] The lower blowout preventer is used to control the well kick and blowout operation of the wellhead sucker rod, and comprises two sets of lower gate plate assemblies, two sets of gate plate shaft assemblies and two sets of limiters; each set of lower gate plate assembly is provided with one set of gate plate shaft assembly and one set of limiter; each set of gate plate shaft assembly is coaxially arranged with the corresponding limiter along the radial direction from inside to outside; the center line of the lower gate plate assembly is coincident with the axis of the gate plate shaft assembly.

[0012] The upper blowout preventer and the lower blowout preventer both adopt the same type and structure of gate plate shaft assembly and limiter, and are arranged from top to bottom along the axial direction of the wellhead sucker rod, and are matched with the housing assembly at the same time.

[0013] Further, the housing assembly comprises a blowout preventer housing, an upper tubing joint, a lower tubing joint, an ear and a housing positioning pin; a double-layer gate plate hole with the same shape and size is milled in the base body of the blowout preventer housing along the length direction, the upper gate plate assembly and the lower gate plate assembly are sequentially arranged in the double-layer gate plate hole, and the gate plate shaft assembly and the limiter are respectively arranged outside the double-layer gate plate hole of the housing assembly; the upper tubing joint and the lower tubing joint are respectively arranged on the upper and lower end faces of the blowout preventer housing along the height direction; two ears are welded on the blowout preventer housing; the housing positioning pin is arranged on the two side end faces of the blowout preventer housing along the length direction, and the housing positioning pin adopts a cylindrical pin.

[0014] Further, the blowout preventer shell adopts a cast steel square body, the double-layered ram holes adopt through holes respectively, the double-layered ram holes are horizontally arranged and cooperated with the upper ram assembly and the lower ram assembly respectively to provide a sliding channel, the four sides of the double-layered ram holes on the two side end faces of the blowout preventer shell along the length direction are uniformly arranged with screw holes in a rectangular array and drilled with layered arranged pin holes, and each pin hole is uniformly arranged in the rectangular array of the screw holes, the cross section of each ram hole in the double-layered ram holes is combined by a rectangular section and two semicircular sections, the two semicircular sections of each ram hole are symmetrically arranged on the two sides of the rectangular section along the width direction of the blowout preventer shell, and the diameter of the semicircular section is equal to the width of the rectangular section. The central part of the blowout preventer shell along the height direction is drilled with a circular hole shaped flow channel, the circular hole shaped flow channel of the blowout preventer shell provides a channel for the heavy oil migration in thermal recovery operation, the circular hole shaped flow channel of the blowout preventer shell is vertically intersected and arranged with the double-layered ram holes, the diameter of the column surface where the circular hole shaped flow channel of the blowout preventer shell is located is greater than the maximum outer diameter of the sucker rod coupling, and the upper and lower ends of the circular hole shaped flow channel are respectively milled with cylindrical clamping rings, the cylindrical clamping rings of the upper end and the lower end of the blowout preventer shell are respectively matched with the upper tubing joint and the lower tubing joint and connected as a whole by welding.

[0015] Further, the upper tubing joint and the lower tubing joint adopt the same type and length of circular pipe body, the outer annular surface side end of the upper tubing joint and the lower tubing joint is machined with pipe threads and matched with the coupling head, and the pipe wall inner diameter of the upper tubing joint and the lower tubing joint is equal to the diameter of the column surface where the circular hole shaped flow channel of the blowout preventer shell is located.

[0016] Further, the upper end face of the blowout preventer shell along the height direction is welded with two lifting lugs with the same shape and size, and the two lifting lugs are symmetrically arranged on the two sides of the upper tubing joint, each lifting lug is vertically arranged and combined by an isosceles trapezoidal steel block and a semicircular steel block, and a lifting hole is drilled at the axis of the semicircular steel block of each lifting lug.

[0017] Further, the one set of shell assembly is respectively configured with two sets of upper ram assemblies and two sets of lower ram assemblies with the same structure, and the two sets of upper ram assemblies and the two sets of lower ram assemblies are symmetrically arranged along the length direction of the blowout preventer shell, the two sets of upper ram assemblies are precisely matched and used to realize the non-metallic sealing between the upper ram and the polished rod and between the upper ram and the blowout preventer shell, the two sets of lower ram assemblies are precisely matched and used to realize the non-metallic sealing between the lower ram and the wellhead sucker rod and between the lower ram and the blowout preventer shell, each set of upper ram assembly includes an upper ram, an upper sealing rubber core and a middle sealing rubber core of the upper ram, and two upper rubber core positioning pins and a middle rubber core positioning rod, and each set of lower ram assembly includes a lower ram, an upper sealing rubber core and a middle sealing rubber core of the lower ram, and two upper rubber core positioning pins and a middle rubber core positioning rod.

[0018] Further, the upper and lower baffle plates are processed from flat square steel blocks, and the front and back faces along the width direction of the blowout preventer shell adopt semi-cylindrical faces, the upper and lower faces of the upper and lower baffle plates and the front and back semi-cylindrical faces are precisely matched with the double-layer baffle hole of the blowout preventer shell to form a four-movement joint of double-plane and double-cylinder combination; the upper end face of the upper and lower baffle plates and the upper half of the front and back semi-cylindrical faces are milled with upper sealing grooves, the upper sealing grooves of the upper and lower baffle plates are configured with upper sealing rubber cores, and the two side groove walls of the upper sealing grooves adopt semi-cylindrical faces and the groove bottom faces adopt planes; the outer side plate bodies of the upper and lower baffle plates along the length direction of the blowout preventer shell are milled with arch-shaped shaft holes, the cross sections of the arch-shaped shaft holes of the upper and lower baffle plates are combined from semi-circular and rectangular shapes, and the hole walls of the arch-shaped shaft holes are provided with multiple ring bearing seat holes arranged in layers at equal intervals, the multiple ring bearing seat holes of the upper and lower baffle plates are matched with the multiple ring thrust bearings provided on the integral baffle plate shaft, the cross sections of the multiple ring bearing seat holes are combined from semi-circular and rectangular shapes, and the specifications of the multiple ring bearing seat holes are greater than those of the arch-shaped shaft holes; the lower end faces of the upper and lower baffle plates are milled with rectangular grooves, the cross sections of the rectangular grooves are rectangular and are placed along the length direction of the blowout preventer shell, and the rectangular grooves of the upper and lower baffle plates realize the communication between the double-layer baffle hole of the blowout preventer shell and the circular hole-shaped flow passage after the upper baffle plate assembly and the lower baffle plate assembly are separated.

[0019] Further, the inner side plate bodies of the upper and lower baffle plates along the length direction of the blowout preventer shell are sequentially provided with centering clamping jaws, centering clamping grooves and middle sealing grooves, the middle sealing groove of the upper baffle plate is configured with an upper baffle plate middle sealing rubber core, the middle sealing groove of the lower baffle plate is configured with a lower baffle plate middle sealing rubber core, the middle sealing grooves of the upper and lower baffle plates are composed of two rectangular sealing grooves and a semi-circular ring-shaped sealing groove, and the two rectangular sealing grooves are symmetrically arranged on the front and back sides of the semi-circular ring-shaped sealing groove, the upper sealing grooves of the upper and lower baffle plates are respectively kept in communication with the two rectangular sealing grooves in the middle sealing grooves, the groove bottom faces of the two rectangular sealing grooves in the middle sealing grooves of the upper and lower baffle plates are respectively drilled with a positioning rod hole, the positioning rod holes are arranged along the length direction of the blowout preventer shell, and the hole bottoms of the positioning rod holes are drilled with positioning pin holes, the positioning pin holes are arranged along the height direction of the blowout preventer shell; the upper and lower parts of the upper and lower baffle plates are respectively arranged with a centering clamping jaw and a centering clamping groove, the centering clamping jaw adopts a sector-shaped steel block, the centering clamping groove adopts a sector-shaped groove, and the centering clamping jaw and the centering clamping groove are precisely matched, thereby realizing the quick centering between the upper baffle plate assembly and the polished rod and between the lower baffle plate assembly and the wellhead sucker rod.

[0020] Further, the upper and lower baffle plates of the middle sealing grooves are drilled with semi-cylindrical butt grooves at the central parts of the upper and lower groove walls, the cylinder face where the semi-cylindrical butt groove of the upper baffle plate is arranged coaxially with the polished rod, and the diameter of the cylinder face where the semi-cylindrical butt groove of the upper baffle plate is arranged is greater than the outer diameter of the polished rod, the cylinder face where the semi-cylindrical butt groove of the lower baffle plate is arranged is coaxial with the wellhead sucker rod, and the diameter of the cylinder face where the semi-cylindrical butt groove of the lower baffle plate is arranged is greater than the outer diameter of the wellhead sucker rod.

[0021] Further, the upper and lower middle sealing rubber cores are each composed of two strip-shaped rubber cores and a semi-circular ring-shaped rubber core, the strip-shaped and semi-circular ring-shaped rubber cores of the upper middle sealing rubber core are respectively in precise fit with the rectangular and semi-circular ring-shaped groove faces of the upper middle sealing groove, and the strip-shaped and semi-circular ring-shaped rubber cores of the lower middle sealing rubber core are respectively in precise fit with the rectangular and semi-circular ring-shaped groove faces of the lower middle sealing groove; the two strip-shaped rubber cores of the upper and lower middle sealing rubber cores are each provided with a positioning rod hole on the outer side sealing contact surface along the length direction of the blowout preventer shell, the semi-circular ring-shaped rubber core of the upper middle sealing rubber core is coaxially arranged with the polished rod along the inner side sealing contact surface of the cylindrical surface, and the diameter of the cylindrical surface is equal to the outer diameter of the polished rod, and the semi-circular ring-shaped rubber core of the lower middle sealing rubber core is coaxially arranged with the wellhead sucker rod along the inner side sealing contact surface of the cylindrical surface, and the diameter of the cylindrical surface is equal to the outer diameter of the wellhead sucker rod.

[0022] Further, the upper sealing rubber core is embedded in the upper sealing groove of the upper and lower blinds, and the sealing contact surfaces of the upper sealing rubber core are in precise fit with the groove faces of the upper sealing groove of the upper and lower blinds. The upper sealing rubber core is provided with a clamping slot on the front and back ends along the width direction of the blowout preventer shell, and the clamping slot of the upper sealing rubber core is in precise fit with the strip-shaped rubber core of the upper and lower middle sealing rubber cores.

[0023] Further, the middle rubber core positioning rod is used to position the upper and lower middle sealing rubber cores in the middle sealing grooves of the upper and lower blinds, and the upper rubber core positioning pin is used to fix the upper sealing rubber core in the upper sealing grooves of the upper and lower blinds.

[0024] Further, the upper rubber core positioning pin and the middle rubber core positioning rod are both cylindrical pins, one side end of the middle rubber core positioning rod is provided with a pin hole, the middle rubber core positioning rod is in clearance fit with the positioning rod hole wall of the upper and lower blinds, and the middle rubber core positioning rod is in interference fit with the positioning rod hole wall of the upper and lower middle sealing rubber cores, so as to position the upper middle sealing rubber core in the upper middle sealing groove of the upper blind and the lower middle sealing rubber core in the lower middle sealing groove of the lower blind.

[0025] Further, the upper rubber core positioning pin is in clearance fit with the positioning pin hole wall of the upper and lower gate plates and the pin hole wall of the middle rubber core positioning rod, while the upper rubber core positioning pin is in interference fit with the positioning pin hole wall of the upper sealing rubber core, thereby realizing the fixation of the upper sealing rubber core in the upper sealing groove of the upper and lower gate plates.

[0026] Further, a set of upper gate plate assembly and lower gate plate assembly are respectively configured with a set of gate shaft assembly of the same type and structure, the gate shaft assembly includes integral gate shaft, retaining ring and positioning nut; the gate shaft assembly transmits motion and power through the integral gate shaft and drives the upper and lower gate plate assemblies to slide along the length direction of the blowout preventer housing by the multi-ring thrust bearing; the positioning nut is a round nut.

[0027] Further, the integral gate shaft is sequentially provided with multi-ring thrust bearing, sliding shaft, positioning shaft, transmission shaft and wrench square along its axial direction, the multi-ring thrust bearing adopts three single-ring thrust bearings which are arranged in layers at equal intervals along the axial direction, when the upper and lower gate plate assemblies are closed, each single-ring thrust bearing is in precise fit between the bearing outer ring along the axial inner side and the axial hole wall surface along the axial inner side of the arch-shaped shaft hole of the upper and lower gate plates to form an inner three-plane rotary pair, when the upper and lower gate plate assemblies are opened, each single-ring thrust bearing is in precise fit between the bearing outer ring along the axial outer side and the axial hole wall surface along the axial outer side of the arch-shaped shaft hole of the upper and lower gate plates to form an outer three-plane rotary pair. The sliding shaft adopts a cylindrical rod body, preferably a long cylindrical rod body, and is provided with a tapered groove at the outer end along the axial direction; the positioning shaft adopts a cylindrical rod body, preferably a short cylindrical rod body, and is threaded at the outer end along the axial direction, and the axial fixation of the retaining ring is realized through the positioning nut and the shoulder formed at the variable diameter joint of the sliding shaft and the positioning shaft, the transmission shaft adopts an elongated rod body and is threaded with trapezoidal transmission outer thread at the inner side along the axial direction, the wrench square adopts a hexagonal square and cooperates with the wrench to realize the rotary motion of the integral gate shaft.

[0028] Further, the retaining ring adopts a flat circular ring body, the inner wall of the ring cavity of the retaining ring is in clearance fit with the outer ring surface of the positioning shaft of the integral gate shaft, and the outer ring surface diameter of the retaining ring is smaller than the inner wall diameter of the ring cavity of the gate shaft seat.

[0029] Further, a set of upper and lower gate board assemblies are respectively configured with a set of same type and structure limiters, the limiter comprises a method flange, a shaft seat flange, a gate board shaft seat, a gate board shaft cover, a side door sealing ring, a Y-shaped sealing ring and an O-shaped sealing ring; the method flange is respectively connected with the blowout preventer shell and the shaft seat flange on both sides; the shaft seat flange is connected with one end of the gate board shaft seat, and the other end of the gate board shaft seat is connected with the gate board shaft cover; the side door sealing ring is arranged on the inner side end surface of the method flange along the length direction of the blowout preventer shell; the Y-shaped sealing ring and the O-shaped sealing ring are arranged on the inner wall of the ring cavity of the central part of the method flange; the limiter realizes the bidirectional limiting of the upper and lower gate board assemblies respectively through the method flange and the shaft seat flange, and realizes the screw transmission of the gate board shaft assembly through the gate board shaft seat.

[0030] Further, the method flange is processed from a rectangular steel block, and a plurality of circular holes are uniformly arranged in the rectangular array around the method flange, the positions and types of the circular holes of the method flange and the screw holes of the blowout preventer shell are same, and the connection between the limiter and the blowout preventer shell is completed through a single head screw. The pin hole is drilled on the method flange, and the positions and types of the pin hole of the method flange and the pin hole of the blowout preventer shell are same, the clearance fit is adopted between the shell positioning pin and the pin hole wall of the blowout preventer shell, and the interference fit is adopted between the shell positioning pin and the pin hole wall of the method flange, so as to realize the positioning of the limiter on the both side end surfaces of the blowout preventer shell along the length direction. The screw holes are uniformly arranged on the outer side end surface of the method flange along the circumferential direction, and the side door sealing groove is milled on the inner side end surface, and the inner side end surface of the method flange is matched with the outer side end surface of the upper and lower gate boards to realize the axial limiting when the upper and lower gate board assemblies are opened respectively, the side door sealing ring is arranged in the side door sealing groove of the method flange, the cross section of the side door sealing ring is circular and realizes the sealing between the method flange and the blowout preventer shell, and the profile of the side door sealing groove of the method flange is same as the cross section of the upper and lower gate boards along the length direction of the blowout preventer shell. The main sealing groove, the auxiliary sealing groove and the cylindrical clamping groove are arranged in the ring cavity inner wall of the central part of the method flange in sequence, the cross section of the main sealing groove of the method flange is right trapezoidal and the Y-shaped sealing ring is arranged in the main sealing groove, the cross section of the Y-shaped sealing ring is Y-shaped and realizes the sealing between the method flange on one side of the double gate board hole of the shell assembly and the integral gate board shaft, the cross section of the auxiliary sealing groove of the method flange is rectangular and the O-shaped sealing ring is arranged in the auxiliary sealing groove, and the cross section of the O-shaped sealing ring is circular and assists the sealing between the method flange and the integral gate board shaft.

[0031] Further, the shaft seat flange adopts a disc-shaped flange, and a circular hole is drilled on the flange disc surface of the shaft seat flange and is uniformly arranged in the circumferential direction, the circular hole of the shaft seat flange is same in position and type with the method flange hole, and the connection between the shaft seat flange and the method flange and the shaft seat of the gate plate is completed through a single-head screw.

[0032] Further, the shaft seat flange adopts a disc-shaped flange, and a circular hole is drilled on the flange disc surface of the shaft seat flange and is uniformly arranged in the circumferential direction, the circular hole of the shaft seat flange is same in position and type with the method flange hole, and the connection between the shaft seat flange and the method flange and the shaft seat of the gate plate is completed through a single-head screw.

[0033] Further, the shaft seat flange adopts a disc-shaped flange, and a circular hole is drilled on the flange disc surface of the shaft seat flange and is uniformly arranged in the circumferential direction, the circular hole of the shaft seat flange is same in position and type with the method flange hole, and the connection between the shaft seat flange and the method flange and the shaft seat of the gate plate is completed through a single-head screw.

[0034] Compared with the prior art, the present application has the following advantages:

[0035] (1) The present application mainly comprises a shell assembly, an upper gate plate assembly, a lower gate plate assembly, a gate plate shaft assembly and a limiter, two sets of upper gate plate assemblies are respectively configured with two sets of gate plate shaft assemblies and two sets of limiters and combined into an upper blowout preventer, the upper blowout preventer is used for controlling the well kick and blowout operation of a polish rod, two sets of lower gate plate assemblies are respectively configured with two sets of gate plate shaft assemblies and two sets of limiters and combined into a lower blowout preventer, the lower blowout preventer is used for controlling the well kick and blowout operation of a wellhead sucker rod, and a non-metallic seal is formed by an upper sealing rubber core, a middle sealing rubber core, a Y-shaped sealing ring and a side door sealing ring, thereby effectively solving the problems of well kick and blowout during the hanging and pumping operation of a heavy oil thermal recovery well;

[0036] (2) The present invention adopts a wrench square diameter and a wrench to rotate an integral gate shaft. Based on the helical pair between the trapezoidal transmission internal thread of the gate shaft seat and the trapezoidal transmission external thread of the integral gate shaft, the internal three-plane rotation pair between the multi-ring thrust bearing and the lower gate, and the four moving pairs of the double plane and double cylindrical surface combination between the lower gate and the blowout preventer housing, the gate shaft assembly transmits motion and power through the integral gate shaft. The upper gate assembly and the lower gate assembly are pushed by the multi-ring thrust bearing to slide along the double-layer gate hole of the blowout preventer housing. The upper gate assembly and the lower gate assembly are axially bidirectionally limited according to the flange and the retaining ring.

[0037] (3) In the process of controlling well inrush and blowout operation of the present invention, the wrench square diameter is matched with the wrench and rotates the integral gate shaft in the opposite direction. Based on the helical pair, the multi-ring thrust bearing and the outer three-plane rotation pair and four moving pairs between the upper gate, the gate shaft assembly transmits motion and power through the integral gate shaft and is pushed by the multi-ring thrust bearing to slide along the double-layer gate hole of the blowout preventer shell until the outer end face of the bearing flange matches the inner end face of the retaining ring along the axial direction to realize the axial limit of the upper gate assembly. The semi-cylindrical docking groove of the upper gate matches the sealing core in the middle of the upper gate and clamps the polished rod. The sealing core in the middle of the upper gate realizes the non-metallic seal between the two sets of upper gates and between the upper gate and the polished rod. The upper sealing core realizes the non-metallic seal between the upper gate and the blowout preventer shell, thereby completing the closing process of the upper gate assembly.

[0038] The wrench square diameter is matched with the wrench and rotates the integral gate shaft in the opposite direction. Based on the helical pair, the external three-plane rotating pair and the four sliding pair between the multi-ring thrust bearing and the upper gate, the gate shaft assembly transmits motion and power through the integral gate shaft and is pushed by the multi-ring thrust bearing to slide the lower gate assembly along the double-layer gate hole of the blowout preventer until the outer end face of the shaft seat flange matches the inner end face of the retaining ring along the axial direction to achieve axial limit of the lower gate assembly. The semi-cylindrical mating groove of the lower gate matches the sealing core in the middle of the lower gate and clamps the wellhead sucker rod. The sealing core in the middle of the lower gate achieves non-metallic sealing between the two sets of lower gates and between the lower gate and the wellhead sucker rod. The upper sealing core achieves non-metallic sealing between the lower gate and the blowout preventer, thereby completing the closing process of the lower gate assembly. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of the structure of the present invention;

[0040] Figure 2 for Figure 1 Top view;

[0041] Figure 3 This is a schematic diagram of the structure of the blowout preventer of the present invention;

[0042] Figure 4 This is a schematic diagram of the structure of the blowout preventer of the present invention;

[0043] Figure 5 Structure diagram of the housing assembly of the present application;

[0044] Figure 6 Structure diagram of the upper ram assembly of the present application; Figure 5 Right view of the present application;

[0045] Figure 7 Structure diagram of the lower ram assembly of the present application;

[0046] Figure 8 Top view of the present application; Figure 7

[0047] Figure 9 Structure diagram of the lower ram assembly of the present application;

[0048] Figure 10 Structure diagram of the ram shaft assembly of the present application;

[0049] Figure 11 Structure diagram of the limiter of the present application;

[0050] Figure 12 Right view of the present application; Figure 11

[0051] Figure 13 Flow chart of the control well kick and blowout operation of the present application.

[0052] In the figure, 1 - housing assembly, 2 - upper ram assembly, 3 - ram shaft assembly, 4 - limiter, 5 - lower ram assembly, 6 - polished rod, 7 - wellhead sucker rod, 8 - upper tubing joint, 9 - lifting lug, 10 - blowout preventer housing, 11 - housing positioning pin, 12 - lower tubing joint, 13 - upper ram middle sealing rubber core, 14 - upper sealing rubber core, 15 - upper ram, 16 - middle rubber core positioning rod, 17 - upper rubber core positioning pin, 18 - lower ram middle sealing rubber core, 19 - lower ram, 20 - integral ram shaft, 21 - blocking ring, 22 - positioning nut, 23 - Y-shaped sealing ring, 24 - O-shaped sealing ring, 25 - side door sealing ring, 26 - method ring, 27 - shaft seat flange, 28 - ram shaft seat, 29 - ram shaft cover, 201 - multi-ring thrust bearing, 202 - sliding shaft, 203 - positioning shaft, 204 - transmission shaft, 205 - wrench square, 301 - rectangular groove. DETAILED DESCRIPTION

[0053] ​​In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art without creative work based on the embodiments in the present application belong to the scope of protection of the present application.

[0054] It should be noted that similar reference numerals and letters represent similar items in the following drawings, and therefore, once an item is defined in one drawing, it need not be further defined and explained in subsequent drawings.

[0055] The present application will be further described below through specific embodiments and in conjunction with the drawings.

[0056] Embodiment 1

[0057] In Figure 1 and Figure 2 , the injection-production integrated pump hanging extraction wellhead blowout preventer involved in the present embodiment comprises a housing assembly 1, an upper gate plate assembly 2, a gate plate shaft assembly 3, a limiter 4 and a lower gate plate assembly 5. The injection-production integrated pump hanging extraction wellhead blowout preventer adopts the upper and middle sealing rubber cores of the upper gate plate assembly 2 and the lower gate plate assembly 5 and the Y-shaped sealing ring 23 and the side door sealing ring 25 of the limiter 4 to form a non-metallic seal, and simultaneously according to the upper gate plate assembly 2, the lower gate plate assembly 5 and the gate plate shaft assembly 3, effectively solves the well kick and blowout problem during the hanging extraction operation of the heavy oil thermal recovery huff and puff well.

[0058] In Figure 1 and Figure 2 , the injection-production integrated pump hanging extraction wellhead blowout preventer is connected with the wellhead packing box through the upper tubing joint 8 and the coupling head of the housing assembly 1, and is integrated with the wellhead tee joint through the lower tubing joint and the coupling head of the housing assembly 1, and the gate plate shaft assembly 3 and the limiter 4 are coaxially arranged along the radial direction from inside to outside.

[0059] In Figure 3 , the center line of the upper gate plate assembly 2 coincides with the axis of the gate plate shaft assembly 3, two sets of the upper gate plate assembly 2 are respectively configured with two sets of the gate plate shaft assembly 3 and two sets of the limiter 4 and combined into an upper blowout preventer, and the upper blowout preventer controls the well kick and blowout operation of the polished rod 6 according to the opening and closing process.

[0060] In Figure 4In the center, the center line of the lower gate plate assembly 5 coincides with the axis of the gate shaft assembly 3, and the two sets of lower gate plate assemblies 5 are respectively arranged with two sets of gate shaft assemblies 3 and two sets of limiters 4 and combined into a lower blowout preventer. The lower blowout preventer controls the well kick and blowout operation of the wellhead sucker rod 7 according to the opening and closing process.

[0061] In Figure 3 and Figure 4 , the upper blowout preventer and the lower blowout preventer of the injection-production integrated pump hanging wellhead blowout preventer both use the same type and structure of gate shaft assembly 3 and limiter 4. The upper blowout preventer and the lower blowout preventer are arranged from top to bottom along the axial direction of the wellhead sucker rod 7 and are matched with the blowout preventer shell of the shell assembly 1.

[0062] In Figure 5 and Figure 6 , the shell assembly 1 includes an upper tubing joint 8, an ear 9, a blowout preventer shell 10, a shell positioning pin 11 and a lower tubing joint 12. The double-layer gate plate hole of the blowout preventer shell 10 is sequentially arranged with the upper gate plate assembly 2 and the lower gate plate assembly 5 and provides a sliding channel for the two. The double-layer gate plate hole of the blowout preventer shell 10 is respectively arranged with the gate shaft assembly 3 and the limiter 4. The cylindrical snap ring at the upper end and the lower end of the blowout preventer shell 10 is matched with the upper tubing joint 8 and the lower tubing joint 12 and is connected as a whole by welding. The circular hole-shaped flow passage of the upper tubing joint 8, the blowout preventer shell 10 and the lower tubing joint 12 simultaneously provides a channel for the migration of heavy oil in thermal recovery operation. Two ears 9 with the same shape and size are welded on the upper end face of the blowout preventer shell 10 and are used for the hoisting operation of the wellhead blowout preventer. The shell positioning pin 11 realizes the positioning of the limiter 4 on the length direction of the two side end faces of the blowout preventer shell 10.

[0063] In Figure 7 and Figure 8In the present application, one set of casing assembly 1 is respectively configured with two sets of upper gate plate assembly 2 with the same structure, and the two sets of upper gate plate assembly 2 are respectively arranged symmetrically along the length direction of blowout preventer casing 10. The two sets of upper gate plate assembly 2 are precisely matched and used to realize the non-metallic sealing between upper gate plate 15 and polished rod 6 and between upper gate plate 15 and blowout preventer casing 10. Each set of upper gate plate assembly 2 includes one upper gate plate 15, upper gate plate upper sealing rubber core 14 and upper gate plate middle sealing rubber core 13, and two upper rubber core positioning pins 17 and middle rubber core positioning rod 16. The precise matching between upper gate plate 15 and blowout preventer casing 10 constitutes four moving pairs of double plane and double cylindrical surface combination. The multi-ring bearing seat hole of upper gate plate 15 is matched with the multi-ring thrust bearing 201 of the integral gate shaft of gate shaft assembly 3. The middle sealing groove of upper gate plate 15 is configured with upper gate plate middle sealing rubber core 13. The upper sealing groove of upper gate plate 15 is configured with upper sealing rubber core 14. The semi-cylindrical butt joint groove of upper gate plate 15 is matched with upper gate plate middle sealing rubber core 13 and clamps polished rod 6. Middle rubber core positioning rod 16 realizes the positioning of upper gate plate middle sealing rubber core 13 in the middle sealing groove of upper gate plate 15. Upper rubber core positioning pin 17 realizes the fixation of upper sealing rubber core 14 in the upper sealing groove of upper gate plate 15. Rectangular grooves 301 are milled on the lower end faces of upper gate plate 15 and lower gate plate 19. The cross section of rectangular grooves 301 is rectangular and is placed along the length direction of blowout preventer casing 10. The rectangular grooves 301 of upper gate plate 15 and lower gate plate 19 realize the communication between the double-layer gate plate hole and the circular hole-shaped flow passage of blowout preventer casing 10 after the separation of upper gate plate assembly 2 and lower gate plate assembly 5.

[0064] In the present application, Figure 9 In the present application, one set of casing assembly 1 is respectively configured with two sets of lower gate plate assembly 5 with the same structure, and the two sets of lower gate plate assembly 5 are respectively arranged symmetrically along the length direction of blowout preventer casing 10. The two sets of lower gate plate assembly 5 are precisely matched and used to realize the non-metallic sealing between lower gate plate 19 and wellhead sucker rod 7 and between lower gate plate 19 and blowout preventer casing 10. Each set of lower gate plate assembly 5 includes one lower gate plate 19, upper sealing rubber core 14 and lower gate plate middle sealing rubber core 18, and two upper rubber core positioning pins 17 and middle rubber core positioning rod 16. The precise matching between lower gate plate 19 and blowout preventer casing 10 constitutes four moving pairs of double plane and double cylindrical surface combination. The multi-ring bearing seat hole of lower gate plate 19 is matched with the multi-ring thrust bearing 201 of the integral gate shaft of gate shaft assembly 3. The middle sealing groove of lower gate plate 19 is configured with lower gate plate middle sealing rubber core 18. The upper sealing groove of lower gate plate 19 is configured with upper sealing rubber core 14. The semi-cylindrical butt joint groove of lower gate plate 19 is matched with lower gate plate middle sealing rubber core 18 and clamps wellhead sucker rod 7. Middle rubber core positioning rod 16 realizes the positioning of lower gate plate middle sealing rubber core 18 in the middle sealing groove of lower gate plate 19. Upper rubber core positioning pin 17 realizes the fixation of upper sealing rubber core 14 in the upper sealing groove of lower gate plate 19.

[0065] In the present application, Figure 10In the present application, a set of upper gate plate assembly 2 and lower gate plate assembly 5 are respectively configured with a set of same type and structure of gate plate shaft assembly 3, which includes integral gate plate shaft 20, retaining ring 21 and positioning nut 22. The integral gate plate shaft 20 is sequentially provided with multi-ring thrust bearing 201, sliding shaft 202, positioning shaft 203, transmission shaft 204 and wrench square 205 along its axial direction. When the upper gate plate assembly 2 and lower gate plate assembly 5 are closed, the multi-ring thrust bearing 201 precisely fits between the upper gate plate 15 and lower gate plate 19 to form an inner three-plane rotary pair. When the upper gate plate assembly 2 and lower gate plate assembly 5 are opened, the multi-ring thrust bearing 201 precisely fits between the upper gate plate 15 and lower gate plate 19 to form an outer three-plane rotary pair. The wrench square 205 cooperates with the wrench to realize the rotary motion of the integral gate plate shaft 20. The retaining ring 21 is axially fixed by the shoulder formed at the variable-diameter joint of the positioning nut 22, sliding shaft 202 and positioning shaft 203 of the integral gate plate shaft 20.

[0066] In the present application, Figure 11 and Figure 12 In the present application, a set of upper gate plate assembly 2 and lower gate plate assembly 5 are respectively configured with a set of same type and structure of gate plate shaft assembly 3, which includes integral gate plate shaft 20, retaining ring 21 and positioning nut 22. The integral gate plate shaft 20 is sequentially provided with multi-ring thrust bearing 201, sliding shaft 202, positioning shaft 203, transmission shaft 204 and wrench square 205 along its axial direction. When the upper gate plate assembly 2 and lower gate plate assembly 5 are closed, the multi-ring thrust bearing 201 precisely fits between the upper gate plate 15 and lower gate plate 19 to form an inner three-plane rotary pair. When the upper gate plate assembly 2 and lower gate plate assembly 5 are opened, the multi-ring thrust bearing 201 precisely fits between the upper gate plate 15 and lower gate plate 19 to form an outer three-plane rotary pair. The wrench square 205 cooperates with the wrench to realize the rotary motion of the integral gate plate shaft 20. The retaining ring 21 is axially fixed by the shoulder formed at the variable-diameter joint of the positioning nut 22, sliding shaft 202 and positioning shaft 203 of the integral gate plate shaft 20.

[0067] In the present application, Figure 11 and Figure 12In the middle, the shaft seat flange 27 of the limiter 4 is connected with the shaft seat flange 27 and the gate shaft seat 28 and the method flange 26 by single head screw, the inner wall of the ring cavity of the shaft seat flange 27 and the auxiliary sealing groove of the method flange 26 are precisely matched with the sliding shaft 202 of the integral gate shaft 20 to form double cylindrical surface moving pairs, the cylindrical box body of the gate shaft seat 28 is matched with the shaft seat groove of the shaft seat flange 27 and is connected as a whole by circumferential welding, the trapezoidal transmission inner thread of the gate shaft seat 28 is precisely matched with the trapezoidal transmission outer thread of the integral gate shaft 20 to form a screw pair, and the gate shaft cover 29 is connected with the gate shaft seat 28 as a whole by single head screw.

[0068] In Figure 13 In the control well kick and blowout operation process of the injection and production integrated pump hanging wellhead blowout preventer, the upper gate plate assembly 2 and the lower gate plate assembly 5 are kept in the open state, the polished rod 6 is lifted and enters the circular hole shaped flow passage of the blowout preventer shell 10, then the wrench square diameter 205 is matched with the wrench and rotates the integral gate shaft 20, according to the screw pair between the trapezoidal transmission inner thread of the gate shaft seat 28 and the trapezoidal transmission outer thread of the integral gate shaft 20, the inner three plane rotary pair between the multi-ring thrust bearing 201 and the upper gate plate 15, and the four moving pairs of double plane and double cylindrical surface combination between the upper gate plate 15 and the blowout preventer shell 10, the gate shaft assembly 3 transmits motion and power through the integral gate shaft 20 and drives the upper gate plate assembly 2 to slide along the double layer gate plate hole of the blowout preventer shell 10 by the multi-ring thrust bearing 201, until the outer side end surface of the shaft seat flange 27 is matched with the inner side end surface of the stop ring 21 in the axial direction to realize the axial limiting of the upper gate plate assembly 2, the semi-cylindrical butt joint groove of the upper gate plate 15 matches the upper gate plate middle sealing rubber core 13 and clamps the polished rod 6, the upper gate plate middle sealing rubber core 13 realizes the non-metallic sealing between the two sets of upper gate plates 15 and between the upper gate plate 15 and the polished rod 6, and the upper sealing rubber core 14 realizes the non-metallic sealing between the upper gate plate 15 and the blowout preventer shell 10, thereby completing the closing process of the upper gate plate assembly 2. Conversely, the wrench square diameter 205 is matched with the wrench and reversely rotates the integral gate shaft 20, according to the screw pair, the outer three plane rotary pair between the multi-ring thrust bearing 201 and the upper gate plate 15, and the four moving pairs, the gate shaft assembly 3 drives the upper gate plate assembly 2 to slide along the double layer gate plate hole of the blowout preventer shell 10, until the inner side end surface of the method flange 26 is matched with the outer side end surface of the upper gate plate 15 to realize the axial limiting of the upper gate plate assembly 2, thereby completing the opening process of the upper gate plate assembly 2.

[0069] In Figure 13In the control well kick and blowout operation process of the injection and pumping integrated pump hanging wellhead blowout preventer, the upper gate plate assembly 2 and the lower gate plate assembly 5 are kept in an open state, the wellhead sucker rod 7 is continuously lifted into the round hole flow passage of the blowout preventer shell 10 through the polished rod 6, then the wrench square 205 cooperates with the wrench and rotates the integral gate shaft 20, according to the spiral pair between the trapezoidal transmission inner thread of the gate shaft seat 28 and the trapezoidal transmission outer thread of the integral gate shaft 20, the inner three-plane rotary pair between the multi-ring thrust bearing 201 and the lower gate plate 19, and the four moving pairs of double-plane and double-cylinder combined between the lower gate plate 19 and the blowout preventer shell 10, the gate shaft assembly 3 transmits motion and power through the integral gate shaft 20 and pushes the lower gate plate assembly 5 to slide along the double-layer gate plate hole of the blowout preventer shell 10 by the multi-ring thrust bearing 201, until the outer side end surface of the shaft seat flange 27 cooperates with the inner side end surface of the blocking ring 21 in the axial direction to realize the axial positioning of the lower gate plate assembly 5, the semi-cylindrical butt joint groove of the lower gate plate 19 cooperates with the lower gate plate middle sealing rubber core 18 and clamps the wellhead sucker rod 7, the lower gate plate middle sealing rubber core 18 realizes the non-metallic sealing between the two sets of lower gate plates 19 and between the lower gate plate 19 and the wellhead sucker rod 7, and the upper sealing rubber core 14 realizes the non-metallic sealing between the lower gate plate 19 and the blowout preventer shell 10, thereby completing the closing process of the lower gate plate assembly 5. Conversely, the wrench square 205 cooperates with the wrench and reversely rotates the integral gate shaft 20, according to the spiral pair, the outer three-plane rotary pair between the multi-ring thrust bearing 201 and the lower gate plate 19, and the four moving pairs, the gate shaft assembly 3 pushes the lower gate plate assembly 5 to slide along the double-layer gate plate hole of the blowout preventer shell 10, until the inner side end surface of the method flange 26 cooperates with the outer side end surface of the lower gate plate 19 to realize the axial positioning of the lower gate plate assembly 5, thereby completing the opening process of the lower gate plate assembly 5.

[0070] The above specific embodiments are only specific cases of the present application, and the patent protection scope of the present application includes but is not limited to the product forms and styles of the above specific embodiments, and any appropriate changes or modifications made by any ordinary skilled person in the art according to the claims of the present application shall fall within the patent protection scope of the present application.

Claims

1. A blowout prevention device for an integrated injection-production pump hanger at the wellhead, characterized in that: Includes the housing assembly, upper blowout preventer, and lower blowout preventer; among which, The injection-production integrated pump hanger wellhead blowout preventer is connected to the wellhead packing box through the upper oil pipe joint and coupling head set on the shell assembly, and is also connected to the wellhead tee through the lower oil pipe joint and coupling head set on the shell assembly. The upper blowout preventer is used to control well kicks and blowouts in polished rod operations, and includes two upper gate assemblies, two gate shaft assemblies, and two limiters; each of the two upper gate assemblies is equipped with a gate shaft assembly and a limiter; each gate shaft assembly and its corresponding limiter are arranged coaxially from the inside to the outside in a radial direction; the centerline of the upper gate assembly coincides with the axis of the gate shaft assembly; The lower blowout preventer is used to control well kick and blowout operations of the wellhead sucker rod, and includes two lower gate assemblies, two gate shaft assemblies, and two limiters; each of the two lower gate assemblies is equipped with a gate shaft assembly and a limiter; each gate shaft assembly and its corresponding limiter are arranged coaxially from the inside to the outside in the radial direction; the centerline of the lower gate assembly coincides with the axis of the gate shaft assembly; The upper and lower blowout preventers both use the same type and structure of gate shaft assembly and limiter. The upper and lower blowout preventers are arranged from top to bottom along the axial direction of the sucker rod at the wellhead and are simultaneously matched with the housing assembly. The housing assembly includes a blowout preventer housing, an upper oil pipe joint, a lower oil pipe joint, lifting lugs, and housing positioning pins. The blowout preventer housing has double-layered gate holes of the same shape and size milled along its length. An upper gate assembly and a lower gate assembly are sequentially arranged within these double-layered gate holes, and a gate shaft assembly and a limiter are respectively arranged outside the double-layered gate holes of the housing assembly. An upper oil pipe joint and a lower oil pipe joint are respectively provided on the upper and lower end faces of the blowout preventer housing along its height. Two lifting lugs are also welded onto the blowout preventer housing. Housing positioning pins are provided on both end faces of the blowout preventer housing along its length. The shell assembly is equipped with two identical upper gate assemblies and two identical lower gate assemblies, which are symmetrically arranged along the length of the blowout preventer shell. The two upper gate assemblies are precisely fitted together to achieve non-metallic seals between the upper gate and the polished rod, and between the upper gate and the blowout preventer shell. The two lower gate assemblies are precisely fitted together to achieve non-metallic seals between the lower gate and the wellhead sucker rod, and between the lower gate and the blowout preventer shell. Each upper gate assembly includes an upper gate and an upper seal. The lower gate assembly includes a lower gate, an upper sealing core, a middle sealing core of the lower gate, two upper sealing core positioning pins, and a middle sealing core positioning rod. The middle sealing core positioning rod is used to position the middle sealing cores of the upper and lower gates respectively within the middle sealing grooves of the upper and lower gates. The upper sealing core positioning pins are used to fix the upper sealing cores within the upper sealing grooves of the upper and lower gates respectively. The upper and lower gate plates are machined from flat rectangular steel blocks, and their front and rear surfaces along the width direction of the blowout preventer housing are semi-cylindrical. The upper and lower end faces and the front and rear semi-cylindrical surfaces of the upper and lower gate plates are precisely fitted with the double-layer gate plate holes of the blowout preventer housing to form a four-moving pair consisting of double planes and double cylinders. The upper end faces and the upper half of the front and rear semi-cylindrical surfaces of the upper and lower gate plates are milled with upper sealing grooves. Upper sealing rubber cores are placed in the upper sealing grooves of the upper and lower gate plates, and the two side walls of the upper sealing grooves are semi-circular. The cylindrical surface and the bottom surface of the groove are flat; the outer side plates of the upper and lower gate plates along the length of the blowout preventer shell are milled with arched shaft holes. The cross-section of the arched shaft holes of the upper and lower gate plates is composed of a combination of semi-circles and rectangles, and the hole walls of the arched shaft holes are provided with multi-ring bearing seat holes arranged in layers at equal intervals. The multi-ring bearing seat holes of the upper and lower gate plates are matched with multi-ring thrust bearings set on the integral gate shaft. The cross-section of the multi-ring bearing seat holes is composed of a combination of semi-circles and rectangles, and the specifications of the multi-ring bearing seat holes are larger than the specifications of the arched shaft holes. The gate shaft assembly includes an integral gate shaft, a retaining ring, and a positioning nut. The integral gate shaft is sequentially provided with a multi-ring thrust bearing, a sliding shaft, a positioning shaft, a transmission shaft, and a wrench square diameter along its axial direction. The multi-ring thrust bearing consists of three single-ring thrust bearings arranged in layers at equal intervals along the axial direction. When the upper and lower gate assemblies are closed, the outer rings of each single-ring thrust bearing along the inner side of the axial direction are precisely fitted with the inner side of the arched shaft holes of the upper and lower gates to form an inner three-plane rotating pair. When the gate is opened, the outer ring of each single-ring thrust bearing along the outer side of the axial direction is precisely fitted with the outer wall of the arched shaft hole of the upper and lower gate to form an outer three-plane rotating pair; the outer end of the sliding shaft along the axial direction is provided with a tapered bevel, the outer end of the positioning shaft along the axial direction is threaded, and the retaining ring is axially fixed by the positioning nut and the shoulder formed at the joint of the sliding shaft and the positioning shaft with the change in diameter; the inner side of the transmission shaft along the axial direction is machined with a trapezoidal transmission external thread; the square diameter of the wrench is matched with the wrench to realize the rotational movement of the integral gate shaft; The limiter includes a flange, a bearing flange, a gate bearing, a gate bearing cover, a side door seal, a Y-shaped seal, and an O-shaped seal. The flange is connected to the blowout preventer housing and the bearing flange on both sides, respectively. The bearing flange is connected to one end of the gate bearing, and the other end of the gate bearing is connected to the gate bearing cover. A side door seal is provided on the inner end face of the flange along the length of the blowout preventer housing. A Y-shaped seal and an O-shaped seal are provided on the inner wall of the annular cavity in the center of the flange. The limiter achieves bidirectional limiting of the upper and lower gate assemblies based on the flange and the bearing flange, and realizes helical drive of the gate bearing assembly through the gate bearing. The gate bearing seat adopts a non-enclosed cylindrical box. The bottom of the cylindrical box is provided with a trapezoidal transmission internal thread and a cylindrical clamp in the radial direction from the inside to the outside. The cylindrical surface where the cylindrical clamp of the gate bearing seat is located is machined with screw holes evenly arranged in the circumferential direction. The trapezoidal transmission internal thread of the gate bearing seat and the trapezoidal transmission external thread of the integral gate shaft are precisely matched to form a helical pair. Based on the helical pair, the multi-ring thrust bearing and the upper gate plate, the three-plane rotating pair and the four moving pair between the upper gate plate, the gate plate shaft assembly pushes the upper gate plate assembly to slide along the double-layer gate plate hole of the blowout preventer housing, and through the cooperation of the outer end face of the bearing flange and the inner end face of the retaining ring along the axial direction, or the inner end face of the flange and the outer end face of the upper gate plate, the bidirectional axial limit of the upper gate plate assembly is achieved. Alternatively, based on the helical pair, the multi-ring thrust bearing and the lower gate plate, the outer three-plane rotating pair and the four moving pairs between them, the gate plate shaft assembly pushes the lower gate plate assembly to slide along the double-layer gate plate hole of the blowout preventer housing, and through the cooperation of the outer end face of the bearing flange and the inner end face of the retaining ring along the axial direction, or the inner end face of the flange and the outer end face of the lower gate plate, the bidirectional axial limit of the lower gate plate assembly is achieved.

2. The injection-production integrated pump-mounted wellhead blowout prevention device according to claim 1, characterized in that: The blowout preventer housing is made of cast steel cuboid. The double-layer gate holes are through holes, arranged horizontally and respectively cooperating with the upper and lower gate assemblies to provide sliding channels. A circular flow channel is drilled in the central part of the blowout preventer housing along the height direction. The circular flow channel of the blowout preventer housing provides a channel for the migration of heavy oil during thermal recovery operations. The circular flow channel of the blowout preventer housing is also arranged perpendicularly to the double-layer gate holes. The diameter of the cylindrical surface where the circular flow channel of the blowout preventer housing is located is larger than the maximum outer diameter of the sucker rod coupling. The upper and lower ends of the circular flow channel are respectively milled with cylindrical retaining rings. The cylindrical retaining rings at the upper and lower ends of the blowout preventer housing are respectively matched with the upper and lower oil pipe joints and connected as a whole by welding.

3. The injection-production integrated pump-mounted wellhead blowout prevention device according to claim 1, characterized in that: The upper and lower gate plates have centering claws, centering grooves, and central sealing grooves sequentially arranged on their inner side plates along the length of the blowout preventer housing. A central sealing core is disposed within the central sealing groove of the upper gate plate, and a central sealing core is disposed within the central sealing groove of the lower gate plate. The central sealing groove of both the upper and lower gate plates consists of two rectangular sealing grooves and a semi-circular annular sealing groove. The two rectangular sealing grooves are symmetrically arranged on the front and rear sides of the semi-circular annular sealing groove. The upper sealing groove of both the upper and lower gate plates is connected to the two rectangular sealing grooves in their respective central sealing grooves. Each of the two rectangular sealing grooves in the middle sealing groove of the gate and the lower gate has a positioning rod hole drilled on its bottom surface. The positioning rod holes are arranged along the length of the blowout preventer housing, and a positioning pin hole is drilled at the bottom of the positioning rod hole. The positioning pin hole is arranged along the height of the blowout preventer housing. The upper and lower parts of the upper and lower gates are respectively equipped with a centering claw and a centering groove. The centering claw is made of fan-shaped steel block, and the centering groove is made of fan-shaped groove. The centering claw and the centering groove are precisely matched, thereby realizing rapid centering between the upper gate assembly and the polished rod, and between the lower gate assembly and the wellhead sucker rod.

4. The injection-production integrated pump-mounted wellhead blowout prevention device according to claim 3, characterized in that: The sealing core in the middle of the upper gate and the middle of the lower gate each consist of two strip-shaped cores and one semi-circular annular core. The sealing contact surfaces of the strip-shaped cores and the semi-circular annular cores in the middle of the upper gate are precisely fitted with the rectangular sealing groove and the semi-circular annular sealing groove of the middle sealing groove of the upper gate. Similarly, the sealing contact surfaces of the strip-shaped cores and the semi-circular annular cores in the middle of the lower gate are precisely fitted with the rectangular sealing groove and the semi-circular annular sealing groove of the middle sealing groove of the lower gate. The upper sealing core has slots at both ends along the width of the blowout preventer housing. These slots are precisely fitted with the sealing contact surfaces of the strip-shaped cores in the middle of the upper and lower gates.

Images