Energy-saving and environment-friendly casing head

Abstract

The invention relates to the field of oil well exploitation equipment, in particular to an energy-saving and environment-friendly casing head which comprises a casing head body, a flange connector, a slip body, a slip bowl and a stop mechanism, and the top of the casing head body is connected with the flange connector through a plurality of bolts; an annular assembling groove is formed in the inner wall of the casing head body, and an inverted-cone-shaped bearing face with the wide upper portion and the narrow lower portion is arranged at the bottom of the annular assembling groove. The slip bowl is arranged in the annular assembling groove, and the inverted-cone-shaped pressing face at the bottom of the slip bowl is in press fit with the inverted-cone-shaped bearing face. The slip body is arranged in the slip bowl, and the lower outer conical surface of the slip body is pressed on the inner conical surface of the slip bowl; the casing head body is connected with a stop mechanism, and the inner end of the stop mechanism abuts against the slip body in a matched mode. The bottom of the flange connector abuts against the stop mechanism in a matched mode. The casing head body and the flange joint are designed into a detachable structure, so that any part can be conveniently replaced when damaged, undamaged parts can be continuously utilized, energy is saved, the environment is protected, and waste is reduced.

Description

Technical Field

[0001] The invention relates to the field of oil well mining equipment, and more specifically to an energy-saving and environment-friendly casing head. Background Art

[0002] The casing head is used to fix the wellhead of the drilled well, connect the wellhead casing string, support the gravity of the technical casing and the oil layer casing, seal the annular space between the layers of pipes, and provide a transition connection for the installation of the blowout preventer and the tubing head. In the prior art, the traditional casing head used in the oil field adopts an integrated flange structure design. The flange and the casing head body cannot be disassembled. If a part of the casing head is damaged, it is not possible to replace only the damaged part, but the whole can only be discarded. For example, if only the flange part is worn, affecting the use effect, because the casing head is an integrated structure, the entire casing head can only be discarded, which is not energy-saving and environmentally friendly, and the material waste is relatively serious. Summary of the invention

[0003] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide an energy-saving and environment-friendly casing head.

[0004] The technical solution adopted by the present invention is:

[0005] An energy-saving and environment-friendly casing head comprises: a casing head body, a flange joint, a slip body, a slip seat and a stopping mechanism, wherein the top of the casing head body is connected to the flange joint by a plurality of bolts; an assembly ring groove is provided on the inner wall of the casing head body, and an inverted conical bearing surface which is wide at the top and narrow at the bottom is provided at the bottom of the assembly ring groove; the slip seat is seated in the assembly ring groove, and an inverted conical pressure surface at the bottom of the slip seat is pressed onto the inverted conical bearing surface; the slip body is seated in the slip seat, and a lower outer conical surface of the slip body is pressed onto an inner conical surface of the slip seat; a stopping mechanism is connected to the casing head body, and an inner end of the stopping mechanism is abutted against the slip body; and the bottom of the flange joint is abutted against the stopping mechanism.

[0006] Furthermore, a first annular groove and a second annular groove are provided on the inner conical surface of the cava seat; the O-ring assembled in the first annular groove abuts against the upper part of the lower outer conical surface of the cava body; the annular expansion airbag assembled in the second annular groove abuts against the lower part of the lower outer conical surface of the cava body.

[0007] Furthermore, the air inlet of the annular expansion airbag is connected to one end of an air pumping pipe passing through the slip seat, and a valve is installed at one end of the air pumping pipe passing through the transverse hole on the side of the casing head body to the outside of the casing head body, and the air pumping pipe is tightly connected to the transverse hole.

[0008] Furthermore, the guide block provided on the side of the slip seat is slidably arranged in the guide longitudinal groove on the inner wall of the casing head body.

[0009] Furthermore, a circular surface with the same upper and lower diameters is provided below the inner conical surface of the cava seat, and a plurality of step grooves are evenly arranged around the middle of the circular surface. A stop push rod is sealingly and slidingly arranged in each step groove, and a reset spring is fixedly connected between the stop push rod and the inner side surface of the step groove. The step groove and the second annular groove are connected through an oblique groove arranged on the cava seat, and the two ends of the oblique pipeline passing through the oblique groove are respectively connected with the step groove and the annular expansion airbag. When the gas in the annular expansion airbag enters the step groove through the oblique pipeline, the stop push rod in the step groove slides toward the center of the cava seat to resist and cooperate with the oil layer casing assembled in the cava body.

[0010] Furthermore, the stepped groove includes: a first annular groove, a second annular groove and a third annular groove which are sequentially connected from the inside to the outside, and the diameters of the first annular groove and the third annular groove are both smaller than the second annular groove; the push rod body of the stop push rod is sealed and slid in the first annular groove, and the limit ring of the stop push rod is sealed and slid in the second annular groove, and the two ends of the reset spring are respectively connected to the push rod body and the inner side surface of the third annular groove, and the third annular groove is connected to the inclined groove.

[0011] Furthermore, the stopping mechanism comprises: a stopping assembly, a plurality of stopping assemblies are evenly connected to the side wall of the casing head body; the stopping assembly comprises: a horizontal screw rod which is sealed and rotated on the side wall of the casing head body, one end of the horizontal screw rod extending through the casing head body is fixedly connected to a handwheel, one end of the horizontal screw rod inserted into the casing head body is threadedly connected to a slide which is slidably arranged in a slide groove of a sliding table of the casing head body, a stopping inclined surface is provided at the inner lower end of a stopping pressure block fixed to the top of the slide; a reinforcing portion is provided between the slide and the stopping pressure block; the stopping inclined surface is matched with an upper outer conical surface arranged above the cava body, and the diameter of the upper outer conical surface decreases successively from top to bottom.

[0012] Furthermore, the stop assembly also includes: a horizontal worm fixed on the inner wall of the casing head body, the horizontal worm and the slide groove are both located in the upper ring groove on the inner side of the casing head body, the upper ring groove is located above the assembly ring groove, the inner end of the horizontal worm is slidably arranged in the horizontal sliding hole at the outer end of the stop pressure block, the horizontal axis 1 connected to the upper surface of the stop pressure block is rotatably connected to the middle of the worm gear, the worm gear passes through the opening groove on the upper surface of the stop pressure block and meshes with the horizontal worm; a sprocket wheel 1 fixed on the horizontal axis 1 is connected to the sprocket wheel 2 on the horizontal axis 2 through a chain, and a cylindrical gear is fixed to the horizontal axis 2 rotatably arranged on the upper surface of the stop pressure block, and a strip groove is provided in the middle of the rack meshing with the top of the cylindrical gear, and the top frame of the portal frame is slidably arranged in the strip groove, the cross bar fixed in the strip groove is passed through the horizontal through hole of the top frame, and the inner end of the rack is connected with an upper stopper for contacting the top of the cava body.

[0013] Furthermore, the upper stop member includes: two longitudinal shafts slidably arranged in the two longitudinal holes of the rack, the outer side of the stop top block fixed to the bottom of the two longitudinal shafts is provided with an outer inclined surface that slides with the inner end of the stop pressure block; a stop spring is sleeved on the shaft body of the longitudinal shaft located between the stop top block and the rack; and a limiting beam fixed to the top of the two longitudinal shafts.

[0014] Furthermore, the stopping mechanism also includes: a bevel gear ring rotated in an outer ring groove on the outer side of the casing head body, the bevel gear ring vertically meshingly connected to a bevel gear fixed on the outer end of the horizontal screw rod; the bottom of the bevel gear ring is connected to a reinforcement ring rotated on the outer side of the casing head body, and a plurality of circular holes evenly arranged around the side wall of the reinforcement ring are fixedly connected with a screw grip tube, and a stop screw threadedly connected in the screw grip tube is abutted against the casing head body.

[0015] Furthermore, the stop ring at the lower end of the inner side surface of the flange joint can be abutted and fitted on the limiting beam.

[0016] It can be seen from the above scheme that the beneficial effects of the present invention are:

[0017] An energy-saving and environmentally friendly casing head of the present invention changes the structural design of the integrated flange of the traditional casing head, and designs the casing head body and the flange joint into a detachable structure, which is convenient for replacement when any component is damaged, so that the undamaged components can continue to be used, saving energy and protecting the environment, and reducing waste; in the present invention, the inner end of the stop mechanism is abutted against the cava body, which can effectively limit the displacement of the cava body in the horizontal and vertical directions, ensuring that it is always in the correct working position, thereby maintaining reliable engagement with the casing, and abutting against the cava body; the bottom of the flange joint is abutted against the stop mechanism, which helps to ensure the sealing of the casing head and reduce the problem of sealing failure caused by loose or deformed components.

[0018] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0020] Figure 1 A schematic diagram of an energy-saving and environmentally friendly casing head provided by an embodiment of the present invention Figure 1 ;

[0021] Figure 2 A schematic diagram of an energy-saving and environmentally friendly casing head provided by an embodiment of the present invention Figure 2 ;

[0022] Figure 3A cross-sectional view of an energy-saving and environmentally friendly casing head provided by an embodiment of the present invention Figure 1 ;

[0023] Figure 4 A cross-sectional view of an energy-saving and environmentally friendly casing head provided by an embodiment of the present invention Figure 2 ;

[0024] Figure 5 A partial schematic diagram of an energy-saving and environmentally friendly casing head provided by an embodiment of the present invention Figure 1 ;

[0025] Figure 6 A partial schematic diagram of an energy-saving and environmentally friendly casing head provided by an embodiment of the present invention Figure 2 ;

[0026] Figure 7 A cutaway view of a casing head body provided by an embodiment of the present invention;

[0027] Figure 8 A schematic diagram of a slip seat provided in an embodiment of the present invention;

[0028] Fig. 9 A cross-sectional view of a slip seat provided in an embodiment of the present invention;

[0029] Fig.10 A schematic diagram of a stop mechanism provided in an embodiment of the present invention;

[0030] Fig.11 Schematic diagram of a stop assembly provided in an embodiment of the present invention Figure 1 ;

[0031] Fig.12 Schematic diagram of a stop assembly provided in an embodiment of the present invention Figure 2 ;

[0032] Fig.13 A schematic diagram of an annular expansion airbag provided in an embodiment of the present invention.

[0033] Icons: casing head body 1; guide longitudinal groove 101; flange joint 2; slip body 3; slip seat 4; guide block 401; step groove 402; stop mechanism 5; stop assembly 500; horizontal screw rod 501; slide 502; stop pressure block 503; reinforcement part 504; horizontal worm 505; horizontal axis 1 506; worm wheel 507; sprocket 1 508; horizontal axis 2 509; sprocket 2 510 ; Cylindrical gear 511; rack 512; gantry 513; cross bar 514; longitudinal axis 515; stop block 516; stop spring 517; limit beam 518; bevel gear ring 519; bevel gear 520; reinforcement ring 521; screw grip tube 522; stop screw 523; O-ring 6; annular expansion airbag 7; inflation tube 8; stop push rod 9; reset elastic member 10; oblique pipeline 11. DETAILED DESCRIPTION

[0034] In order to clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention, it is obvious that the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] It should be understood that the terms such as “having”, “including” and “comprising” used herein do not exclude the existence or addition of one or more other elements or combinations thereof.

[0036] Example 1

[0037] See also Figure 1-Figure 13 The present invention provides an energy-saving and environmentally friendly casing head, comprising: a casing head body 1, a flange joint 2, a slip body 3, a slip seat 4 and a stopping mechanism 5, wherein the top of the casing head body 1 is connected to the flange joint 2 by a plurality of bolts; an assembly ring groove is provided on the inner wall of the casing head body 1, and an inverted conical bearing surface which is wide at the top and narrow at the bottom is provided at the bottom of the assembly ring groove; the slip seat 4 is seated in the assembly ring groove, and the inverted conical pressure surface at the bottom of the slip seat 4 is pressed on the inverted conical bearing surface; the slip body 3 is seated in the slip seat 4, and the lower outer conical surface of the slip body 3 is pressed on the inner conical surface of the slip seat 4; a stopping mechanism 5 is connected to the casing head body 1, and the inner end of the stopping mechanism 5 is abutted against the slip body 3; the bottom of the flange joint 2 is abutted against the stopping mechanism 5.

[0038] The working principle and technical effect of the above technical scheme are as follows: an energy-saving and environmentally friendly casing head of the present invention changes the structural design of the integrated flange of the traditional casing head, and designs the casing head body 1 and the flange joint 2 into a detachable structure. The top of the casing head body 1 is connected to the flange joint 2 by multiple bolts, and the disassembly and assembly are very simple, which is convenient for replacement when any component is damaged, so that the undamaged components can be continuously utilized, which is energy-saving and environmentally friendly and reduces waste; in the present invention, the flange joint 2 is used to connect other pipelines or equipment, and the assembly ring groove of the casing head body 1 has an inverted conical bearing surface for installing the slip seat 4, and the inverted slip seat 4 at the bottom is The conical pressure surface and the inverted conical bearing surface cooperate with each other to achieve a tight fit through the conical structure, thereby playing a supporting role; the cava body 3 is placed in the cava seat 4, and the lower outer conical surface is pressed onto the inner conical surface of the cava seat 4 to form a wedge-shaped structure. When there is pressure, the cava body 3 will be compressed, thereby fixing the oil layer casing inside the cava body 3; the inner end of the stopping mechanism 5 contacts the cava body 3, and the bottom of the flange joint 2 also contacts the stopping mechanism 5. When the flange joint is fixed by bolts, the stopping mechanism 5 will be pressed downward to assist in fixing the cava body 3 and prevent it from moving. During installation, a pre-tightening force can be generated by tightening the bolts to enhance the sealing and stability.

[0039] During installation, the cava seat 4 is placed in the assembly ring groove of the casing head body 1, the cava body 3 is placed in the cava seat 4, and the stop mechanism 5 supports the cava body 3 and generates pressure on it, so that the cava body 3 and the cava seat 4 are tightly pressed together, and when the flange joint 2 is connected by bolts, the flange joint 2 presses the stop mechanism 5, so that the entire structure is stable, and the lower outer conical surface of the cava body 3 is pressed on the inner conical surface of the cava seat 4. The design of the conical surface generates radial extrusion force when subjected to pressure, thereby enhancing the sealing and fixing effect. The cava body 3 may be used to clamp the casing oil layer to prevent it from moving up and down, and the conical structure becomes tighter and tighter when subjected to force, thereby improving the bearing capacity; in addition, in the present invention, by forming a stable sealing structure, leakage can be reduced, thereby reducing energy loss; the cooperation of the inverted conical bearing surface and the inverted conical pressure surface can disperse stress and extend the service life; the present invention has the following advantages:

[0040] 1. The inverted conical pressure surface at the bottom of the slip seat 4 cooperates with the inverted conical bearing surface of the casing head body 1 to form a "wedge effect". When the oil layer casing is subjected to axial load, the friction between the conical surfaces and the radial component force work together to produce a self-locking effect and enhance the compressive stability.

[0041] 2. The lower outer conical surface of the slip body 3 is pressed together with the inner conical surface of the slip seat 4 to form a double conical locking structure, which further disperses the load and improves the clamping force.

[0042] 3. After the flange joint 2 is fastened by bolts, its bottom directly presses the stop mechanism 5, pushing the inner end of the stop mechanism 5 to press against the slip body 3, forming axial fixation, converting the installation action of the flange joint 2 into active locking of the slip system, which is conducive to realizing the integrated operation of "installation and locking".

[0043] 4. The slip seat 4 and the assembly ring groove adopt a pre-assembled design. During assembly, you only need to embed the slip seat 4 into the groove, and automatically align the center through the conical surface, which reduces the manual calibration steps and improves the installation efficiency;

[0044] 5. Improved sealing performance: The double conical surface pressing structure (slip seat 4-casing head body 1, slip body 3-slip seat 4) forms a multi-level sealing barrier, which significantly reduces the risk of wellhead medium leakage and the environmental pollution caused by oil and gas escape, meeting environmental protection requirements.

[0045] 6. Failure protection mechanism: If the slip body 3 undergoes a slight displacement due to abnormal load, the stop mechanism 5 can provide secondary constraint through rigid contact with the flange joint 2 to prevent sudden failure and improve wellhead safety.

[0046] Example 2

[0047] See also Figure 1-Figure 13The inner conical surface of the cava seat 4 is provided with a first annular groove and a second annular groove; the O-ring 6 assembled in the first annular groove abuts against the upper side of the lower outer conical surface of the cava body 3; the annular expansion airbag 7 assembled in the second annular groove abuts against the lower side of the lower outer conical surface of the cava body 3.

[0048] The working principle and technical effects of the above technical solution are as follows:

[0049] The O-ring 6 assembled in the first annular groove contacts the upper part of the lower outer cone of the cava body 3. The O-ring 6 has good elasticity and sealing performance. When the cava body 3 is placed in the cava seat 4, the O-ring 6 will be squeezed and deformed, filling the tiny gap between the inner cone of the cava seat 4 and the lower outer cone of the cava body 3, preventing the fluid in the well from leaking from this part, and can effectively prevent the leakage of media such as high-pressure oil and gas and drilling fluid, thereby ensuring the safety and environmental protection of oil well operations; the annular expansion airbag 7 assembled in the second annular groove contacts the lower part of the lower outer cone of the cava body 3. The annular expansion airbag 7 can be inflated and expanded by external control to further squeeze the slip body 3, so that the fit between it and the slip seat 4 is tighter. On the basis of the O-ring seal 6, the annular expansion airbag 7 provides additional sealing protection. In particular, when facing complex working conditions or when the O-ring seal 6 is slightly worn, the annular expansion airbag 7 can make up for the sealing defects and ensure a good sealing effect; the O-ring seal 6 and the annular expansion airbag 7 apply pressure on the upper and lower sides of the lower outer cone of the slip body 3 respectively. This pressure distribution helps to keep the slip body 3 in the slip seat 4 The stable position and uniform radial pressure can prevent the cava body 3 from shaking or displacing during operation, ensuring that the cava body 3 can continuously and reliably bite the casing, thereby improving the overall stability and bearing capacity of the casing head; during oil well operations, the oil well casing will be affected by various vibrations and impacts, and these external forces may cause the fit between the cava body 3 and the cava seat 4 to loosen. The O-ring 6 and the annular expansion airbag 7 have a certain elasticity, which can absorb and buffer these vibrations and impacts, reduce damage to the cava body 3 and the cava seat 4, and extend their service life.

[0050] In actual production, there may be certain dimensional errors in the manufacture of the cava body 3 and the cava seat 4. The elastic properties of the O-ring 6 and the annular expansion airbag 7 can compensate for these dimensional errors to ensure that the cava body 3 and the cava seat 4 can always be well matched. Even when there are certain manufacturing tolerances in the components, the sealing performance and stability of the casing head can be guaranteed.

[0051] The air inlet of the annular expansion airbag 7 is connected to one end of the air pumping pipe 8 penetrating the slip seat 4. The air pumping pipe 8 passes through the transverse through hole on the side of the casing head body 1 to the outside of the casing head body 1. A valve is installed at one end, and the air pumping pipe 8 is tightly connected with the transverse through hole. The guide block 401 provided on the side of the slip seat 4 is slidably provided in the guide longitudinal groove 101 on the inner wall of the casing head body 1.

[0052] The working principle and technical effects of the above technical solution are as follows:

[0053] The annular expansion airbag 7 actively controls the sealing contact force through the inflation pressure, and can adjust the airbag expansion amount in real time according to the downhole pressure fluctuation (for example: inflating and pressurizing to compensate the seal under low-pressure conditions, and depressurizing under high-pressure conditions to avoid excessive squeezing). Compared with the fixed preload of the passive deformation of the rubber ring, the sealing reliability is effectively improved, and the leakage rate of the annular expansion airbag 7 is lower than that of the rubber ring; in the present invention, the annular expansion airbag 7 adopts a high-temperature resistant silicon-based composite material, and the expansion coefficient is stable under conditions of -50°C to 200°C, and the increase in the sealing gap caused by wear can be compensated by supplementing air pressure. The annular continuous inflation structure of the annular expansion airbag 7 can make the sealing force evenly distributed 360° along the lower outer conical surface of the cava body 3, eliminating the rubber ring due to eccentric installation or local wear. The pressure concentration point caused by damage; the annular expansion airbag 7 is in contact with the lower outer cone surface of the slip body 3, forming a double barrier of "mechanical cone surface pressing + airbag flexible sealing": primary sealing: the metal cone surface pressing of the slip body and the slip seat prevents the invasion of large particle media; secondary sealing: the airbag blocks the penetration of micron-level fluids, especially for small molecular corrosive gases such as CO2 and H2S. The sealing effect is remarkable; in the present invention, the sliding cooperation between the guide block 401 and the guide longitudinal groove 101 realizes precise axial positioning, limits the circumferential rotation of the slip seat 4, and improves the installation accuracy; in addition, the continuous expansion force of the airbag can offset the micro-displacement of the slip body caused by vibration, and the guide longitudinal groove also bears the anti-shear effect, reducing the lateral displacement of the slip seat under the wellhead impact load.

[0054] Example 3

[0055] See also Figure 1-Figure 13 A circular surface with the same upper and lower diameters is provided below the inner conical surface of the cava seat 4, and a plurality of step grooves 402 are evenly arranged around the middle of the circular surface. A stop push rod 9 is sealingly and slidingly arranged in each step groove 402, and a reset elastic member 10 is fixedly connected between the stop push rod 9 and the inner side surface of the step groove 402. The step groove 402 is connected to the second annular groove through an inclined groove arranged on the cava seat 4, and the two ends of the inclined pipeline 11 passing through the inclined groove are respectively connected to the step groove 402 and the annular expansion airbag 7. When the gas in the annular expansion airbag 7 enters the step groove 402 through the inclined pipeline 11, the stop push rod 9 in the step groove 402 slides toward the center of the cava seat 4 to abut against and cooperate with the oil layer casing assembled in the cava body 3.

[0056] The working principle and technical effects of the above technical solution are as follows:

[0057] When the annular expansion airbag 7 is inflated, the gas is evenly distributed to each stepped groove 402 through the inclined pipeline 11, pushing all the stop push rods 9 to slide synchronously toward the center, forming a 360° uniformly distributed radial force. The uniform distribution and synchronous action of multiple stop push rods 9 form a "multi-point pushing effect", which can automatically correct the initial deflection of the oil layer casing during installation; in the present invention, while controlling the annular expansion airbag 7 through the air pump 8, all the stop push rods 9 can be driven synchronously without manual adjustment one by one, and the installation efficiency is effectively improved. If a stop push rod 9 is stuck, the air pressure will preferentially fill other stepped grooves 402 through the inclined pipeline 11 to ensure that at least 75% of the push rods are normally applied, and the redundant design avoids single-point failure leading to overall loss of control; multiple stop push rods 9 apply pressure to the oil layer casing from different directions, which can greatly enhance the fixing effect of the present invention on the oil layer casing and effectively reduce the shaking, displacement or rotation of the oil layer casing in the well. During the oil well exploitation process, the oil layer casing will be affected by various external forces such as the flow of the fluid in the well and the movement of the formation. This additional fixation can improve the stability of the oil layer casing and ensure the normal production of the oil well. The design realizes an automatic response mechanism based on the pressure change of the annular expansion airbag 7. With the change of the oil well working conditions, such as pressure fluctuations, the pressure in the annular expansion airbag 7 will also change accordingly. In the oil well operation, the change of working conditions (such as pressure fluctuations) will directly affect the pressure in the annular expansion airbag 7. When the pressure in the oil well increases, the annular expansion airbag 7 is compressed by the external pressure, and the pressure in the airbag increases accordingly, which is higher than the pressure in the stepped groove 402. According to the gas pressure balance principle, the gas always flows from a high pressure place to a low pressure place, so at this time, the gas in the annular expansion airbag 7 will flow into the stepped groove 402 through the inclined pipeline 11. As the gas flows into the stepped groove 402, the pressure in the stepped groove 402 gradually increases, pushing the stop push rod 9 to slide toward the center of the slip seat 4, so that the stop push rod 9 contacts the oil layer casing and increases the resistance to it. When the pressure in the step groove 402 reaches equilibrium with the pressure in the annular expansion airbag 7, the gas stops flowing, and the stop push rod 9 also stops moving and remains in the current position to adapt to the new working pressure. On the contrary, when the pressure in the oil well decreases, the external pressure on the annular expansion airbag 7 decreases, the airbag begins to expand, and the internal pressure decreases, which is lower than the pressure in the step groove 402. At this time, the gas in the step groove 402 will flow back to the annular expansion airbag 7 through the inclined pipeline 11, the pressure in the step groove 402 decreases, and the stop push rod 9 slides away from the oil layer casing under the action of the reset elastic member 10, reducing the resistance to the oil layer casing until a new pressure balance is established. The stop push rod 9 is sealed and slidable in the step groove 402, which can prevent the fluid in the well from leaking through the step groove 402, thereby ensuring the sealing performance of the casing head. At the same time, the setting of the reset elastic member 10 enables the stop push rod 9 to return to the initial position under the action of the reset elastic member 10 when the pressure in the annular expansion airbag 7 decreases.This not only facilitates the installation and removal of the sleeve, but also ensures that the stop push rod 9 can still maintain a good working condition after multiple uses.

[0058] Multiple stop push rods 9 are assembled on the oil layer casing in the slip body 3 in a resistance fit, which can play a role in centering and calibrating the oil layer casing to a certain extent; multiple stop push rods 9 are evenly arranged on the annular surface, and when they simultaneously apply resistance force to the oil layer casing, a relatively uniform radial force field will be formed. If the oil layer casing has a certain eccentricity, this uniform radial force will cause the oil layer casing to move to the center position, thereby achieving centering and calibration.

[0059] The stepped groove 402 includes: a first annular groove, a second annular groove and a third annular groove which are sequentially connected from the inside to the outside, and the diameters of the first annular groove and the third annular groove are both smaller than the second annular groove; the ejector rod body of the stop ejector rod 9 is sealed and slidably arranged in the first annular groove, and the limiting ring of the stop ejector rod 9 is sealed and slidably arranged in the second annular groove, and the two ends of the reset elastic member 10 are respectively connected to the ejector rod body and the inner side surface of the third annular groove, and the third annular groove is connected to the inclined groove.

[0060] This scheme designs the stepped groove 402 into a specific structure, and makes the stop push rod 9 and the reset elastic member 10 cooperate therewith. The push rod body of the stop push rod 9 is sealed and slidably arranged in the first annular groove. The first annular groove provides a precise guiding effect for the sliding of the push rod body, so that the stop push rod 9 can move smoothly along a fixed path when sliding toward the center of the cava seat 4 to contact the oil layer casing, or when sliding and resetting in the reverse direction, to avoid shaking or deviation, thereby ensuring the accuracy and stability of its movement; the limiting ring of the stop push rod 9 is sealed and slidably arranged in the second annular groove. Since the diameters of the first annular groove and the third annular groove are both smaller than those of the second annular groove, when the limiting ring slides in the second annular groove, it is restricted by the annular groove structure and will not fall out of the stepped groove 402, thereby ensuring It ensures that the stop push rod 9 is always in the step groove 402, maintains the integrity and reliability of the entire device, and avoids the situation where the stop push rod 9 falls out and causes the oil layer casing to fail to be fixed; the push rod body slides in a sealing manner in the first annular groove, and the limit ring slides in a sealing manner in the second annular groove. This multi-position sealing design can effectively prevent the gas leakage in the step groove 402. When the gas enters or flows out of the step groove 402 through the inclined pipeline 11, the good sealing performance ensures that the pressure can be effectively transmitted, so that the stop push rod 9 can accurately adjust the position and resistance force according to the pressure change of the annular expansion airbag 7, and at the same time, it also prevents the fluid in the well from leaking to the outside through the step groove 402, thereby ensuring the safety and environmental protection of the oil well operation.

[0061] Example 4

[0062] See also Figure 1-Figure 13The stop mechanism 5 includes: a stop assembly 500, a plurality of stop assemblies 500 are evenly connected to the side wall of the casing head body 1; the stop assembly 500 includes: a horizontal screw rod 501 which is sealed and rotated on the side wall of the casing head body 1, one end of the horizontal screw rod 501 extending through the casing head body 1 is fixedly connected to a handwheel, one end of the horizontal screw rod 501 inserted into the casing head body 1 is threadedly connected to a slide 502 which is slidably arranged in the slide groove of the slide of the casing head body 1, and a stop inclined surface is provided at the lower end of the inner side of a stop pressure block 503 fixed to the top of the slide 502; a reinforcement portion 504 is provided between the slide 502 and the stop pressure block 503; the stop inclined surface is arranged in cooperation with the upper outer conical surface arranged above the slip body 3, and the diameter of the upper outer conical surface decreases from top to bottom.

[0063] The working principle and technical effect of the above technical scheme are as follows: rotating the hand wheel can drive the horizontal screw rod 501 to rotate, and the rotation of the horizontal screw rod 501 can change its contact position with the slide 502, thereby driving the slide 502 to approach or move away from the slip body 3 in the slide groove; when it is necessary to control the slip body 3 to hold the oil layer casing tightly, the slide 502 is controlled to move in the slide groove toward the slip body 3, and the slide 502 drives the stop pressure block 503 to move, so that the stop inclined surface of the stop pressure block 503 is pressed on the upper outer conical surface above the slip body 3; the stop assembly 500 of the present invention is easy to operate, and rotating the hand wheel can drive the horizontal screw rod 501 to rotate, thereby controlling the slide 503 and the stop pressure block 503 Movement, this manual operation method does not require complex power equipment and control systems. The operator can adjust the degree of clamping of the cava body 3 to the oil layer casing at any time according to actual needs, which is convenient and quick; the horizontal screw rod 501 is connected to the slide 502 by a thread, which has high precision and controllability, and can accurately control the moving distance and direction of the slide 502 in the slide groove of the slide, thereby realizing the precise adjustment of the clamping force of the cava body 3 to ensure that the oil layer casing is stably fixed. The present invention has two, when the stop bevel of the stop pressure block 503 is pressed on the upper outer cone surface above the cava body, due to the action of the bevel, a pressure perpendicular to the bevel will be generated, and this pressure can be decomposed into an axial component and a radial component. The axial component helps to press the cava body 3 downward, while the radial component will cause the cava body 3 to have a tendency to shrink toward the center, thereby enhancing the clamping force of the cava body 3 on the oil layer casing;

[0064] A plurality of stop assemblies 500 are evenly connected to the side wall of the casing head body 1, and the stop bevel of each stop assembly 500 cooperates with the upper outer conical surface of the cava body. The evenly distributed design makes the clamping force on the cava body 3 in the circumferential direction more uniform, avoiding the situation where the local clamping force is too large or too small, ensuring that the oil layer casing can be stably clamped in all directions, and improving the reliability of the clamping effect; and the structure of the coordinated bevel enables the cava body 3 to better resist the axial and radial movement of the oil layer casing when clamping the oil layer casing. During the operation of the oil well, the oil layer casing will be affected by various external forces, such as the flow of fluid, the movement of the formation, etc. The cooperation between the stop bevel and the upper outer conical surface can effectively disperse and transmit these external forces, thereby improving the stability of the cava body in clamping the oil layer casing and reducing the risk of the oil layer casing loosening.

[0065] The stop assembly 500 also includes: a horizontal worm 505 fixedly mounted on the inner wall of the casing head body 1, the horizontal worm 505 and the slideway groove are both located in the upper ring groove on the inner side of the casing head body 1, the upper ring groove is located above the assembly ring groove, the inner end of the horizontal worm 505 is slidably mounted in the horizontal sliding hole at the outer end of the stop pressure block 503, a worm wheel 507 is fixedly connected in the middle of the horizontal axis 506 rotatably connected to the upper surface of the stop pressure block 503, and the worm wheel 507 passes through the open groove on the upper surface of the stop pressure block 503 and meshes with the horizontal worm 505; Sprocket 1 508 fixed on 1 506 is connected to sprocket 2 510 on transverse axis 2 509 through a chain, and a cylindrical gear 511 is fixedly connected to transverse axis 2 509 which is rotated on the upper surface of the stop pressure block 503. A strip groove is provided in the middle of a rack 512 meshingly connected to the top of the cylindrical gear 511, and a top frame of a portal frame 513 is slidably arranged in the strip groove. A cross bar 514 fixed in the strip groove is passed through a transverse through hole of the top frame, and an upper stopper for abutting against the top of the cava body 3 is connected to the inner end of the rack 512. The upper stopper comprises: two longitudinal shafts 515 slidably arranged in the two longitudinal holes of the rack 512; a stopper top block 516 fixedly connected to the bottom of the two longitudinal shafts 515 has an outer inclined surface on the outer side thereof which is slidably matched with the inner end of the stopper pressure block 503; a stopper spring 517 is sleeved on the shaft body of the longitudinal shaft 515 located between the stopper top block 516 and the rack 512; and a limiting beam 518 fixedly connected to the top of the two longitudinal shafts 515.

[0066] The working principle and technical effect of the above technical solution are as follows: when the control slide 502 moves in the slide slot toward the direction of the cava body 3, the worm wheel 507 rolls on the horizontal worm 505, thereby driving the horizontal axis 1 506 and the sprocket 1 508 to rotate. At this time, the sprocket 1 508 can drive the horizontal axis 2 509 to rotate through the cooperation of the chain and the sprocket 2 510, and the horizontal axis 2 509 drives the cylindrical gear 511 to rotate, so that the cylindrical gear 511 meshes with the rack 512 to move in the direction of the cava body 3. Under normal conditions, the stop top block 516 shrinks and contacts the upper surface of the stop pressure block 503, and the rack 512 drives the upper The stopper moves in the direction of the slip body 3. When the stopper top block 516 of the upper stopper is separated from the stop pressure block 503, the stopper top block 516 is pressed against the upper surface of the slip body 3 under the elastic force of the stop spring 517, thereby locking the slip body 3 in multiple directions. When the stopper top block 516 of the upper stopper is separated from the stop pressure block 503, it is pressed against the upper surface of the slip body 3 under the elastic force of the stop spring 517, thereby locking the slip body 3 in multiple directions. When controlling the slip body 3 to hold the oil layer casing tightly, in addition to the stop pressure block 503 applying pressure from the side, the stopper top block 516 applies pressure from the top The multi-directional locking is realized by resisting the slip body 3. The multi-dimensional constraint mode can better resist various complex external forces on the oil layer casing in the well, such as axial tension, radial vibration, etc., effectively preventing the slip body 3 from loosening or displacement, and greatly enhancing the stability of the slip body 3 holding the oil layer casing; the multi-directional locking makes the external force on the slip body 3 more evenly dispersed, avoiding the situation where the slip body 3 is damaged or the holding failure caused by excessive local force; the locking forces in various directions cooperate with each other and work together to ensure the stable holding of the slip body 3 to the oil layer casing, improving the overall oil well. Reliability of the casing fixing system; during oil well operation, the working conditions will continue to change, such as pressure fluctuations, temperature changes, etc. These changes may cause slight displacement or deformation of the oil layer casing. The multi-directional locking method can enable the cava body 3 to better adapt to these working condition changes. The stop top block 516 can automatically adjust the resistance force under the elastic force of the stop spring 517, and timely make up for the gap caused by the change in working conditions, always maintain effective locking of the cava body 3, and ensure that the fixing effect of the oil layer casing is not affected by the change in working conditions; the elastic force of the stop spring 517 can be adjusted according to actual needs. Under different oil well working conditions, the resistance force of the stop top block 516 on the cava body 3 can be changed by replacing springs with different elastic coefficients or adjusting the preload force of the spring, thereby achieving flexible adjustment of the locking force of the cava body 3 to meet different clamping requirements; the linear motion of the slide 502 is converted into the displacement of the rack 512 through the worm chain drive. When the top block 516 disengages from the stop pressure block 503, the spring force is instantly released to achieve zero-delay automatic locking without manual intervention.The stop spring 517 plays the role of elastic buffer to prevent overload. The stiffness curve of the stop spring 517 has been optimized. It quickly fits the slip surface in the initial stage and increases resistance nonlinearly in the high-pressure stage, reducing the damage caused by deformation of the slip body 3 due to hard contact.

[0067] Among them, the stop ring at the lower end of the inner side surface of the flange joint 2 can be abutted and fitted on the limiting beam 518, so that the stop top block 516 produces a more stable locking effect on the slip body 3.

[0068] The stop mechanism 5 further includes: a bevel gear ring 519 rotated in the outer ring groove on the outer side of the casing head body 1, the bevel gear ring 519 vertically meshingly connected to the bevel gear 520 fixed on the outer end of the horizontal screw rod 501; the bottom of the bevel gear ring 519 is connected to the reinforcement ring 521 rotated on the outer side of the casing head body 1, and a plurality of circular holes uniformly arranged around the side wall of the reinforcement ring 521 are fixedly connected with a screw grip tube 522, and a stop screw 523 threadedly connected in the screw grip tube 522 is abutted and fitted on the casing head body 1. When the screw grip tube 522 is held to control the rotation of the reinforcement ring 521, the bevel gear ring 519 can be driven to rotate, so that the bevel gear ring 519 meshes with the plurality of bevel gears 520 to rotate, and the bevel gears 520 drive the plurality of horizontal screw rods 501 to rotate synchronously, so that the synchronous control of the plurality of stop assemblies 500 can be realized, which is conducive to improving the centering locking effect of the plurality of stop assemblies 500 on the slip body 3.

[0069] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0070] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0071] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes, and they can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the illustrations shown and described herein.

Claims

1. An energy-saving and environmentally friendly casing head, characterized in that: include: A casing head body, a flange joint, a slip body, a slip seat and a stopping mechanism, wherein the top of the casing head body is connected to the flange joint by a plurality of bolts; an assembly ring groove is provided on the inner wall of the casing head body, and an inverted conical bearing surface which is wide at the top and narrow at the bottom is provided at the bottom of the assembly ring groove; the slip seat is seated in the assembly ring groove, and the inverted conical pressure surface at the bottom of the slip seat is pressed on the inverted conical bearing surface; the slip body is seated in the slip seat, and the lower outer conical surface of the slip body is pressed on the inner conical surface of the slip seat; a stopping mechanism is connected to the casing head body, and the inner end of the stopping mechanism is abutted against the slip body; the bottom of the flange joint is abutted against the stopping mechanism.

2. The energy-saving and environmentally friendly casing head according to claim 1, characterized in that: The inner conical surface of the slip seat is provided with a first annular groove and a second annular groove; the O-ring installed in the first annular groove abuts against the upper part of the lower outer conical surface of the slip body; the annular expansion airbag installed in the second annular groove abuts against the lower part of the lower outer conical surface of the slip body.

3. The energy-saving and environmentally friendly casing head according to claim 2, characterized in that: The air inlet of the annular expansion airbag is connected to one end of an air pumping pipe penetrating the slip seat. The air pumping pipe passes through a transverse through hole on the side of the casing head body and a valve is installed at one end outside the casing head body. The air pumping pipe is tightly connected to the transverse through hole.

4. The energy-saving and environmentally friendly casing head according to claim 3, characterized in that: The guide block on the side of the slip seat is slidably arranged in the guide longitudinal groove on the inner wall of the casing head body.

5. The energy-saving and environmentally friendly casing head according to claim 3, characterized in that: A circular surface with the same upper and lower diameters is provided below the inner conical surface of the cava seat, and a plurality of step grooves are provided in the middle of the circular surface. A stop push rod is sealingly and slidingly provided in each step groove, and a reset elastic member is fixedly connected between the stop push rod and the inner side surface of the step groove. The step groove and the second annular groove are connected through an inclined groove provided on the cava seat, and the two ends of the inclined pipeline passing through the inclined groove are respectively connected with the step groove and the annular expansion airbag. When the gas in the annular expansion airbag enters the step groove through the inclined pipeline, the stop push rod in the step groove slides toward the center of the cava seat to abut and fit against the oil layer casing in the cava body.

6. The energy-saving and environmentally friendly casing head according to claim 5, characterized in that: The stepped groove includes: a first annular groove, a second annular groove and a third annular groove which are sequentially connected from the inside to the outside, and the diameters of the first annular groove and the third annular groove are both smaller than the second annular groove; the ejector rod body of the stop ejector rod is sealed and slidably arranged in the first annular groove, and the limiting ring of the stop ejector rod is sealed and slidably arranged in the second annular groove, and the two ends of the reset elastic member are respectively connected to the ejector rod body and the inner side surface of the third annular groove, and the third annular groove is connected to the inclined groove.

7. The energy-saving and environmentally friendly casing head according to claim 1, characterized in that: The stopping mechanism comprises: a stopping assembly, a plurality of stopping assemblies are evenly connected to the side wall of the casing head body; the stopping assembly comprises: a horizontal screw rod which is sealed and rotated on the side wall of the casing head body, one end of the horizontal screw rod which passes through the casing head body is fixedly connected to a handwheel, one end of the horizontal screw rod which is inserted into the casing head body is threadedly connected to a slide which is slidably arranged in a slide groove of the casing head body slide, a stopping inclined surface is arranged at the lower end of the inner side of a stopping pressure block which is fixedly connected to the top of the slide; a reinforcing portion is arranged between the slide and the stopping pressure block; the stopping inclined surface is arranged in cooperation with an upper outer conical surface arranged above the slip body, and the diameter of the upper outer conical surface decreases successively from top to bottom.

8. The energy-saving and environmentally friendly casing head according to claim 7, characterized in that: The stop assembly also includes: a horizontal worm fixed on the inner wall of the casing head body, the horizontal worm and the slide groove are both located in the upper ring groove on the inner side of the casing head body, the upper ring groove is located above the assembly ring groove, the inner end of the horizontal worm is slidably arranged in the horizontal sliding hole at the outer end of the stop pressure block, the horizontal axis 1 connected to the upper surface of the stop pressure block is fixed with a worm gear in the middle, and the worm gear passes through the opening groove on the upper surface of the stop pressure block and meshes with the horizontal worm; a sprocket wheel 1 fixed on the horizontal axis 1 is connected to the sprocket wheel 2 on the horizontal axis 2 through a chain, and a cylindrical gear is fixed to the horizontal axis 2 rotatably arranged on the upper surface of the stop pressure block, and a strip groove is provided in the middle of the rack meshing with the top of the cylindrical gear, and the top frame of the portal frame is slidably arranged in the strip groove, and the cross bar fixed in the strip groove is passed through the horizontal through hole of the top frame, and the inner end of the rack is connected with an upper stopper for contacting the top of the cava body.

9. The energy-saving and environmentally friendly casing head according to claim 8, characterized in that: The upper stopper comprises: two longitudinal shafts slidably arranged in the two longitudinal holes of the rack, the outer side of the stop top block fixedly connected to the bottom of the two longitudinal shafts is provided with an outer inclined surface which slides with the inner end of the stop pressure block; a stop spring is sleeved on the shaft body of the longitudinal shaft located between the stop top block and the rack; and a limiting beam is fixedly connected to the top of the two longitudinal shafts.

10. The energy-saving and environmentally friendly casing head according to claim 9, characterized in that: The stop ring at the lower end of the inner side surface of the flange joint can be abutted and fitted on the limiting beam.

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