Energy-saving and environmentally friendly casing head

Abstract

The present invention relates to the field of oil well mining equipment, and more specifically, to an energy-saving and environmentally friendly casing head, comprising: a casing head body, a flange joint, a slip body, a slip seat, and a stop mechanism. The top of the casing head body is connected to the flange joint via a plurality of bolts. The inner wall of the casing head body is provided with an annular assembly groove, and the bottom of the annular assembly groove is provided with an inverted conical bearing surface that is wide at the top and narrow at the bottom. The slip seat is seated in the annular assembly groove, and the 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 the lower outer conical surface of the slip body is pressed onto the inner conical surface of the slip seat. The casing head body is connected to a stop mechanism, and the inner end of the stop mechanism abuts against the slip body. The bottom of the flange joint abuts against the stop mechanism. The casing head body and the flange joint are designed to be detachable, so that they can be replaced when any component is damaged, thereby allowing the undamaged component to continue to be used, saving energy and protecting the environment, and reducing waste.

Description

Technical Field

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

[0002] The casing head is used to secure 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 pipe, and provide a transition connection for the installation of the blowout preventer and the tubing head. In the existing technology, the traditional casing head used in oil fields adopts an integrated flange structure design. The flange and the casing head body cannot be separated. If a part of the casing head is damaged, it cannot be replaced alone and the entire casing head must be discarded. For example, if only the flange part is worn, affecting the performance, the casing head must be discarded because it is a one-piece structure. This is not energy-saving and environmentally friendly, and it wastes a lot of materials. 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 environmentally friendly casing head.

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

[0005] An energy-saving and environmentally 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 wider at the top and narrower 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 onto 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 onto 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.

[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 the air pumping pipe passing through the slip seat. The air pumping pipe passes through the transverse hole on the side of the casing head body to the outside of the casing head body. A valve is installed at one end of the air pumping pipe and 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 stepped grooves are evenly arranged around the middle of the circular surface. A stop push rod is sealed and slidably 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 inclined groove provided on the cava seat, and the two ends of the inclined pipeline passing through the inclined groove are respectively connected to 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 resist and cooperate with the oil layer casing assembled in the cava body.

[0010] Furthermore, the stepped groove includes: a first ring groove, a second ring groove and a third ring groove that are connected in sequence from the inside to the outside, and the diameters of the first ring groove and the third ring groove are both smaller than the second ring groove; the push rod body of the stop push rod is sealed and slid in the first ring groove, and the limiting ring of the stop push rod is sealed and slid in the second ring 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 ring groove, and the third ring groove is connected to the oblique groove.

[0011] Furthermore, the stopping mechanism includes: a stopping assembly, a plurality of stopping assemblies are evenly connected to the side wall of the casing head body; the stopping assembly includes: a horizontal screw rod sealed and rotated on the side wall of the casing head body, one end of the horizontal screw rod passes through the casing head body and is fixed to a handwheel, one end of the horizontal screw rod is inserted into the casing head body and is threadedly connected to a slide slidably arranged in the slide groove of the casing head body, and a stopping inclined surface is provided at the lower end of the inner side of the stopping pressure block fixed to the top of the slide; a reinforcement portion is provided between the slide and the stop pressure block; the stopping inclined surface is cooperated with the upper outer conical surface arranged above the cava body, and the diameter of the upper outer conical surface decreases 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 slot 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 shaft 1 connected to the upper surface of the stop pressure block is fixed with a worm gear in the middle, the worm gear passes through the open groove on the upper surface of the stop pressure block and meshes with the horizontal worm; a sprocket 1 fixed on the horizontal shaft 1 is connected to the sprocket 2 on the horizontal shaft 2 through a chain, and a cylindrical gear is fixed on the horizontal shaft 2 rotated on the upper surface of the stop pressure block, and a strip slot is provided in the middle of the rack meshing with the top of the cylindrical gear, and the top frame of the gantry is slid in the strip slot, and the cross bar fixed in the strip slot is passed through the horizontal through hole of the top frame, and the inner end of the rack is connected with an upper stop piece 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 the outer ring groove on the outer side of the casing head body, the bevel gear ring is vertically meshed with the bevel gear fixed on the outer end of the horizontal screw rod; the bottom of the bevel gear ring is connected to the 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 fixed with screw grip tubes, and the stop screw threadedly connected in the screw grip tube is in contact with 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] As can be seen from the above scheme, the beneficial effects of the present invention are:

[0017] The 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 component can continue to be used, saving energy and being environmentally friendly, and reducing waste; in the present invention, the inner end of the stop mechanism is in friction fit on 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 through friction fit with the cava body; the bottom of the flange joint is in friction fit on 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 Schematic diagram of an energy-saving and environmentally friendly casing head provided by an embodiment of the present invention Figure 1 ;

[0021] Figure 2 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 cross-sectional view of a casing head body provided in 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] Figure 9 A cross-sectional view of a slip seat provided in an embodiment of the present invention;

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

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

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

[0032] Figure 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; stepped groove 402; stop mechanism 5; stop assembly 500; horizontal screw rod 501; slide 502; stop pressure block 503; reinforcement 504; horizontal worm 505; horizontal axis 1 506; worm gear 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; limiting 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; inclined 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 accompanying drawings below, it is obvious that the embodiments described are only part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

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

[0036] Example 1

[0037] See also Figures 1-13 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. The top of the casing head body 1 is connected to the flange joint 2 by multiple bolts; the inner wall of the casing head body 1 is provided with an assembly ring groove, and the bottom of the assembly ring groove is provided with an inverted conical bearing surface that is wide at the top and narrow at the bottom; 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 in contact with the slip body 3; the bottom of the flange joint 2 is in contact with the stopping mechanism 5.

[0038] The working principle and technical effect of the above technical solution 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, which is very simple to disassemble and assemble, and is convenient for replacing when any component is damaged, so that the undamaged components can be continued to be used, which is energy-saving and environmentally friendly and reduces waste; in the present invention, the flange joint 2 is used to connect other pipes 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 bottom of the slip seat 4 is provided with a groove. The conical pressure surface and the inverted conical bearing surface cooperate with each other to achieve a tight fit through the conical structure, which plays a supporting role; the slip body 3 is placed in the slip seat 4, and the lower outer conical surface is pressed on the inner conical surface of the slip seat 4 to form a wedge structure. When there is pressure, the slip body 3 will be compressed, thereby fixing the oil layer casing inside the slip body 3; the inner end of the stop mechanism 5 contacts the slip body 3, and the bottom of the flange joint 2 also contacts the stop mechanism 5. When the flange joint is fixed by bolts, the stop mechanism 5 will be pressed downward to assist in fixing the slip body 3 and prevent it from moving. During installation, a pre-tightening force can be generated by tightening the bolts to enhance 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 presses against the cava body 3 and generates pressure on it, so that the cava body 3 and the cava seat 4 are tightly pressed together. Moreover, when the flange joint 2 is connected by bolts, the flange joint 2 presses the stop mechanism 5, thereby making the entire structure stable. The lower outer conical surface of the cava body 3 is pressed against the inner conical surface of the cava seat 4. The design of the conical surface generates radial extrusion force when under 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 under 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 combination of the inverted conical bearing surface and the inverted conical pressure surface can disperse stress and extend 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 tightened 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, and 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 insert the slip seat 4 into the groove, and the tapered surface will automatically align the centering position, reducing manual calibration steps and improving installation efficiency.

[0044] 5. Improved sealing performance: The double-cone pressed structure (slip seat 4-casing head body 1, slip body 3-slip seat 4) forms a multi-stage sealing barrier, significantly reducing 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 Figures 1-13The inner conical surface of the slip 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 slip 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 slip 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 is in contact with the upper part of the lower outer conical surface of the slip body 3. The O-ring 6 has good elasticity and sealing performance. When the slip body 3 is placed in the slip seat 4, the O-ring 6 will be squeezed and deformed, filling the tiny gap between the inner conical surface of the slip seat 4 and the lower outer conical surface of the slip 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, drilling fluid, etc., to ensure the safety and environmental protection of oil well operations; the annular expansion airbag 7 assembled in the second annular groove is in contact with the lower part of the lower outer conical surface of the slip body 3. The annular expansion airbag 7 can be inflated by external control to further squeeze the slip body 3, making the fit between it and the slip seat 4 tighter. On the basis of the O-ring seal 6, the annular expansion airbag 7 provides additional sealing protection, especially when facing complex working conditions or when the O-ring 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 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, and 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 slip body 3 from shaking or displacing during operation, ensuring that the slip 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 slip body 3 and the slip 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 slip body 3 and the slip 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, ensuring that the cava body 3 and the cava seat 4 can always be well matched, and 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 bag 7 is connected to one end of an air pump 8 that passes through the slip seat 4. The air pump 8 passes through a transverse hole on the side of the casing head body 1 and is installed at one end of the casing head body 1. The air pump 8 is tightly connected to the transverse hole. The guide block 401 provided on the side of the slip seat 4 is slidably mounted 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 for 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 working 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 caused by 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 of the slip body 3, forming a double barrier of "mechanical cone 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 the sealing effect on small molecular corrosive gases such as CO2 and H2S; 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 Figures 1-13 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 stepped grooves 402 are evenly arranged around the middle of the circular surface. A stop push rod 9 is sealed and slidably arranged in each stepped groove 402, and a reset elastic member 10 is fixedly connected between the stop push rod 9 and the inner side surface of the stepped groove 402. The stepped groove 402 and the second annular groove are connected through an inclined groove provided on the cava seat 4, and the two ends of the inclined pipeline 11 passing through the inclined groove are respectively connected with the stepped groove 402 and the annular expansion airbag 7. When the gas in the annular expansion airbag 7 enters the stepped groove 402 through the inclined pipeline 11, the stop push rod 9 in the stepped groove 402 slides toward the center of the cava seat 4 to resist 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 pipe 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 pipe 11 to ensure that at least 75% of the push rods are normally applied force, 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 oil well production, the reservoir casing is subject to various external forces, such as the flow of well fluids and formation movement. This additional fixation can improve the stability of the reservoir casing and ensure normal oil well production. This design implements an automatic response mechanism based on the pressure changes of the annular expansion bladder 7. As the oil well operating conditions change, such as pressure fluctuations, the pressure within the annular expansion bladder 7 also changes accordingly. During oil well operations, changes in operating conditions (such as pressure fluctuations) directly affect the pressure within the annular expansion bladder 7. When the pressure within the oil well increases, the annular expansion bladder 7 is compressed by the external pressure, and the pressure within the bladder increases, exceeding the pressure within the stepped groove 402. According to the principle of gas pressure balance, gas always flows from high pressure to low pressure. Therefore, at this time, the gas within the annular expansion bladder 7 will flow into the stepped groove 402 through the inclined pipe 11. As the gas flows into the stepped groove 402, the pressure within the stepped groove 402 gradually increases, pushing the stop rod 9 toward the center of the slip seat 4, causing the stop rod 9 to contact the reservoir casing and increase the resistance force. When the pressure in the stepped groove 402 reaches equilibrium with the pressure in the annular expansion bladder 7, the gas stops flowing, and the stop rod 9 also stops moving and remains in its current position to adapt to the new operating pressure. Conversely, when the pressure in the oil well decreases, the external pressure on the annular expansion bladder 7 decreases, the bladder begins to expand, and the internal pressure decreases, becoming lower than the pressure in the stepped groove 402. At this time, the gas in the stepped groove 402 will flow back into the annular expansion bladder 7 through the inclined pipe 11, the pressure in the stepped groove 402 decreases, and the stop 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 rod 9 is sealed and slidable in the stepped groove 402, which prevents the fluid in the well from leaking through the stepped groove 402 and ensures the sealing performance of the casing head. At the same time, the setting of the reset elastic member 10 ensures that when the pressure in the annular expansion bladder 7 decreases, the stop rod 9 can return to its initial position under the action of the reset elastic member 10.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 rods 9 are fitted against the oil-bearing casing within the slip body 3, providing a certain degree of centering and calibration. These rods 9 are evenly arranged around the annular surface. When they simultaneously apply a resisting force to the oil-bearing casing, they create a relatively uniform radial force field. If the oil-bearing casing is eccentric, this uniform radial force forces it toward the center, achieving centering and calibration.

[0059] The stepped groove 402 includes: a first ring groove, a second ring groove and a third ring groove which are connected in sequence from the inside to the outside, and the diameters of the first ring groove and the third ring groove are both smaller than the second ring groove; the ejector rod body of the stop ejector rod 9 is sealed and slid in the first ring groove, and the limiting ring of the stop ejector rod 9 is sealed and slid in the second ring 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 ring groove, and the third ring groove is connected to the inclined groove.

[0060] This solution designs the stepped groove 402 into a specific structure, and makes the stop push rod 9 and the reset elastic member 10 cooperate with it. The push rod body of the stop push rod 9 is sealed and slidable in the first annular groove. The first annular groove provides a precise guide 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 in the process of reverse sliding and resetting, avoiding shaking or deviation, thereby ensuring the accuracy and stability of its movement; the limiting ring of the stop push rod 9 is sealed and slidable in the second annular groove. Since the diameters of the first annular groove and the third annular groove are 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, ensuring This ensures that the stop push rod 9 is always in the stepped groove 402, maintains the integrity and reliability of the entire device, and avoids the situation where the oil layer casing is not fixed properly due to the stop push rod 9 falling out; the push rod body slides in a sealed manner in the first annular groove, and the limit ring slides in a sealed manner in the second annular groove. This multi-position sealing design can effectively prevent gas leakage in the stepped groove 402. When the gas enters or flows out of the stepped 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 also prevents the fluid in the well from leaking to the outside through the stepped groove 402, thereby ensuring the safety and environmental protection of the oil well operation.

[0061] Example 4

[0062] See also Figures 1-13The stop mechanism 5 includes: a stop assembly 500, multiple 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 sealed and rotated on the side wall of the casing head body 1, the horizontal screw rod 501 passes through one end of the casing head body 1 and is fixed to the handwheel, and one end of the horizontal screw rod 501 is inserted into the casing head body 1 and is threadedly connected to a slide 502 slidably arranged in the slide groove of the casing head body 1, and a stop pressure block 503 fixed to the top of the slide 502 is provided with a stop inclined surface on the inner lower end; a reinforcement portion 504 is provided between the slide 502 and the stop pressure block 503; the stop inclined surface is cooperated with the upper outer conical surface provided on the top of 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 solution are as follows: rotating the handwheel can drive the horizontal screw rod 501 to rotate, and the rotation of the horizontal screw rod 501 can change the contact position between the horizontal screw rod 501 and the slide 502, thereby driving the slide 502 to move closer to or 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, the slide 502 is controlled to move in the direction of the slip body 3 in the slide groove, 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 handwheel 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, thereby realizing 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 stopping inclined surface of the stop pressure block 503 is pressed on the upper outer conical surface above the cava body, due to the action of the inclined surface, a pressure perpendicular to the inclined surface 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 to 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 inclined surface cooperation 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 fixed on the inner wall of the casing head body 1, the horizontal worm 505 and the slide 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 arranged in the horizontal sliding hole at the outer end of the stop pressure block 503, and a worm gear 507 is fixed in the middle of the horizontal axis 506 rotatably connected to the upper surface of the stop pressure block 503, and the worm gear 507 passes through the open groove on the upper surface of the stop pressure block 503 and engages with the horizontal worm 505; the horizontal axis Sprocket 1 508 fixed on 1 506 is connected to sprocket 2 510 on horizontal shaft 2 509 through a chain, and a cylindrical gear 511 is fixed to horizontal shaft 2 509 which is rotated on the upper surface of the stop pressure block 503. A strip groove is provided in the middle of the rack 512 which is meshed with the top of the cylindrical gear 511, and a top frame of a portal frame 513 is slidably arranged in the strip groove. The cross bar 514 fixed in the strip groove is passed through the horizontal through hole of the top frame, and the inner end of the rack 512 is connected to an upper stopper for contacting the top of the cava body 3. The upper stop member includes: two longitudinal shafts 515 slidably arranged in the two longitudinal holes of the rack 512, and the outer side of the stop top block 516 fixed to the bottom of the two longitudinal shafts 515 is provided with an outer inclined surface that slides with the inner end of the stop pressure block 503; a stop spring 517 is sleeved on the shaft body of the longitudinal shaft 515 located between the stop top block 516 and the rack 512; and a limiting beam 518 fixed 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 groove toward the direction of the slip body 3, the worm wheel 507 rolls on the horizontal worm 505, thereby driving the horizontal shaft 1 506 and the sprocket 1 508 to rotate. At this time, the sprocket 1 508 can drive the horizontal shaft 2 509 to rotate through the cooperation of the chain and the sprocket 2 510, and the horizontal shaft 2 509 drives the cylindrical gear 511 to rotate, so that the cylindrical gear 511 engages the rack 512 to move toward the direction of the slip 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 When the upper stopper 516 is released from the stop pressure block 503, the stopper 516 is pressed against the upper surface of the slip body 3 by the elastic force of the stop spring 517, thereby locking the slip body 3 in multiple directions. When the upper stopper 516 is released from the stop pressure block 503, the stopper 516 is pressed against the upper surface of the slip body 3 by the elastic force of the stop spring 517, thereby locking the slip body 3 in multiple directions. The multi-directional locking is achieved by resisting the slip body 3. The multi-dimensional constraint method can better resist various complex external forces on the oil layer casing in the well, such as axial tension, radial vibration, etc., and effectively prevent the slip body 3 from loosening or displacement, which greatly enhances 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 stability of the entire 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 changes 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 damage caused by deformation of the slip body 3 due to hard contact.

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

[0068] The locking mechanism 5 further includes a bevel gear ring 519 mounted within an outer ring groove on the outer side of the casing head body 1. The bevel gear ring 519 vertically meshes with a bevel gear 520 fixed to the outer end of the horizontal screw rod 501. The bottom of the bevel gear ring 519 is connected to a reinforcement ring 521 mounted on the outer side of the casing head body 1. Multiple circular holes uniformly arranged around the sidewall of the reinforcement ring 521 are fixedly connected to screw grips 522. A stop screw 523 threaded into the screw grips 522 engages with the casing head body 1. When the screw grips 522 are gripped to rotate the reinforcement ring 521, the bevel gear ring 519 is rotated. The bevel gear ring 519 then meshes with the multiple bevel gears 520, which in turn drive the multiple horizontal screw rods 501 to rotate synchronously. This allows for synchronous control of the multiple locking assemblies 500, thereby improving the centering and locking effect of the multiple locking assemblies 500 on the slip body 3.

[0069] In the description of the present invention, it should 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" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying 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 specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0071] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the description and implementation methods. 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 illustrations shown and described herein.

Claims

1. An energy-saving and environmentally friendly casing head, characterized in that: include: The casing head body, flange joint, slip body, slip seat and stop mechanism are provided. The top of the casing head body is connected to the flange joint by multiple bolts. The inner wall of the casing head body is provided with an assembly ring groove, and the bottom of the assembly ring groove is provided with an inverted conical bearing surface that is wide at the top and narrow at the bottom. 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 onto 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 onto the inner conical surface of the slip seat. The casing head body is connected to a stop mechanism, and the inner end of the stop mechanism is in contact with the slip body. The bottom of the flange joint is in contact with the stop mechanism. The stop mechanism includes: a stop assembly, a plurality of stop assemblies evenly connected to the side wall of the casing head body; the stop assembly includes: a horizontal screw rod 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 slidably arranged in a slide groove of the casing head body slide, a stop inclined surface is provided on the lower end of the inner side of the stop pressure block fixed to the top of the slide; a reinforcement portion is provided between the slide and the stop pressure block; the stop inclined surface is cooperated with the upper outer conical surface provided on the upper part of the slip body, and the diameter of the upper outer conical surface decreases from top to bottom; The stop assembly also includes: a horizontal worm fixed on the inner wall of the casing head body, the horizontal worm and the slide slot 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 shaft 1 connected to the upper surface of the stop pressure block is fixed with a worm gear in the middle, the worm gear passes through the open groove on the upper surface of the stop pressure block and meshes with the horizontal worm; a sprocket 1 fixed on the horizontal shaft 1 is connected to the sprocket 2 on the horizontal shaft 2 through a chain, and a cylindrical gear is fixed on the horizontal shaft 2 rotated on the upper surface of the stop pressure block, and a strip slot 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 slid in the strip slot, and the cross bar fixed in the strip slot is passed through the horizontal through hole of the top frame, and the inner end of the rack is connected with an upper stop piece for contacting the top of the cava body.

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 assembled in the first annular groove abuts against the upper part of the lower outer conical surface of the slip body; the annular expansion airbag assembled 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 the air pumping pipe passing through the slip seat. The air pumping pipe passes through the transverse through hole on the side of the casing head body and is installed with a valve 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 stepped grooves are provided in the middle of the circular surface. A stop push rod is sealed and slidably provided in each stepped groove, and a reset elastic member is fixedly connected between the stop push rod and the inner side surface of the stepped groove. The stepped 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 stepped groove and the annular expansion airbag. When the gas in the annular expansion airbag enters the stepped groove through the inclined pipeline, the stop push rod in the stepped groove slides toward the center of the cava seat to abut 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 slid in the first annular groove, and the limiting ring of the stop ejector rod is sealed and slid 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 oblique groove.

7. The energy-saving and environmentally friendly casing head according to claim 1, characterized in that: 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.

8. The energy-saving and environmentally friendly casing head according to claim 7, 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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