A geothermal wellhead casing centralizer

Abstract

The application discloses a geothermal well mouth casing centralizer, characterized in that the centralizer comprises a fixing base and a centralizing mechanism arranged on the fixing base; the centralizing mechanism comprises a containing groove arranged on the fixing base, a sliding block contained in the containing groove, an elastic member arranged between the sliding block and the containing groove, and a driving member for driving the sliding block to move relative to the containing groove; an insertion groove is arranged on the inner wall of a geothermal well mouth casing head and corresponds to the containing groove; and the driving member is used for driving the sliding block to be inserted into the insertion groove or to be withdrawn from the insertion groove. The geothermal well mouth casing centralizer can effectively seal and center the casing, and a through hole with a certain thickness does not need to be arranged on a four-way joint assembly or a casing head assembly to install a jacking screw, so that the centralizer is simple to install, the centralizing structure with a cladding design can reduce heat loss in a well, and the service life of components can be effectively prolonged.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of valve, in particular to a centralizer suitable for geothermal wellhead casing. BACKGROUND

[0002] The geothermal wellhead device is installed on the wellhead of the upper end of the geothermal well pipe, which is a device for closing the wellhead, connecting the pipeline, facilitating water extraction, recharge and data collection. It is used to pump hot water in the geothermal well up, and the cooling water formed after the heat energy of the hot water is utilized is transported into the geothermal well through the wellhead device. Its feature is that it includes a casing, a hot water output pipeline and a cooling water return pipeline. One end of the casing is threadedly connected with the wellhead of the geothermal well, and the other end is connected with the hot water output pipeline and the cooling water return pipeline. A flow meter is arranged at the connection between the casing and the hot water output pipeline and the cooling water return pipeline. The casing head is generally provided with a flange gate valve, a pressure gauge and a plurality of valves.

[0003] In the existing geothermal wellhead device, the centralizer is usually fixed by a top screw, which takes a long time to install. The casing head assembly needs to be drilled, which may cause heat dissipation. In addition, the centralizer is unevenly stressed, which further reduces the reliability of installation and sealing of the geothermal wellhead device and its service life. SUMMARY

[0004] Therefore, in order to overcome the defects of the prior art, the purpose of the present application is to provide an improved geothermal wellhead casing centralizer which is easy to install and has good centralizing effect on the casing.

[0005] In order to achieve the above purpose, the technical scheme adopted by the present application is as follows:

[0006] A geothermal wellhead casing centralizer, characterized in that: the centralizer comprises a fixing seat and a centralizing mechanism arranged on the fixing seat, the centralizing mechanism comprises a containing groove arranged on the fixing seat, a sliding block contained in the containing groove, an elastic member arranged between the sliding block and the containing groove, and a driving member for driving the sliding block to move relative to the containing groove, an insertion groove is arranged on the inner wall of the geothermal wellhead casing head corresponding to the containing groove, and the driving member is used to drive the sliding block to insert into or withdraw from the insertion groove. When the geothermal wellhead device is actually working, the pressure in the well can drive the casing to reciprocate up and down, and the centralizer plays a role of centralizing, centering and sealing the casing. In addition, the centralizing structure in the present application does not need to drill a hole through the thickness on the four-way assembly or the casing head assembly to install the top screw, and the centralizing structure with the covering design can reduce the heat loss in the well.

[0007] According to some preferred embodiments of the present application, the accommodating groove extends along the radial direction of the fixing base; the length of the sliding block is less than or equal to the depth of the accommodating groove, and the elastic member is used to provide the sliding block with a tendency to be inserted into the insertion groove.

[0008] According to some preferred embodiments of the present application, the accommodating groove is a blind hole which is opened along the radial direction of the fixing base and has an opening facing the inner wall of the casing head assembly. The elastic member is preferably a spring which is arranged in the same direction as the accommodating groove. The spring is arranged to balance the pressure of the well medium when the sliding block driving fails or the pressure of the well is too large, so as to prevent the sliding block from retreating into the accommodating groove of the fixing base and avoid the centralizer being pushed out by the pressure of the well.

[0009] According to some preferred embodiments of the present application, one end of the sliding block near the insertion groove is provided with an insertion slope, and the other end of the sliding block is provided with a limiting part for limiting the elastic member, and the limiting part forms a limiting groove for accommodating one end of the elastic member. That is, the sliding block is provided with an over-round on one side to avoid the failure of the spline of the sliding block and the failure of the installation of the sliding block.

[0010] According to some preferred embodiments of the present application, a tooth groove is arranged on the sliding block, the driving member sequentially comprises a connecting part, a threaded part and a gear part, the threaded part is threadedly connected with the fixing base, the gear part is provided with a gear for engaging with the tooth groove, and the gear is inserted into the tooth groove to drive the sliding block to move by rotating the driving member. That is, the driving part is in the form of a screw. When the centralizer is installed, the sliding block is retreated into the accommodating groove of the fixing base by adjusting the screw. Then, the centralizer is installed into the casing head, and after the centralizer is stably positioned in the casing head, the sliding block is extended out of the accommodating groove of the fixing base and the end thereof is inserted into the insertion groove by adjusting the screw.

[0011] The tooth groove is arranged on the top of the sliding block, and a horizontal key tooth is arranged on one side of the tooth groove. The width of the tooth groove is greater than the maximum diameter of the spline, so that the gear part can be inserted into the tooth groove and engage with the key tooth. The top of the screw is provided with an internal hexagonal groove for adjusting. The middle part of the screw is provided with a thread for threadedly cooperating with the positioning hole of the fixing base, so that the gear part at the bottom is stably positioned in the gear groove on the top of the sliding block. The gear part is provided with a spline for cooperating with the key tooth in the gear groove to drive the sliding block.

[0012] According to some preferred embodiments of the present application, the inner wall of the casing head is provided with a positioning slope for positioning the fixing base, and the lower part of the fixing base is provided with a positioning surface matched with the inner wall of the casing head. The positioning slope on the inner wall of the casing head and the positioning surface on the fixing base are used to fix the position of the centralizer in the casing head, so as to ensure the subsequent centralizing effect.

[0013] According to some preferred embodiments of the present application, the inner diameter of the fixing seat matches the outer diameter of the casing, and the outer diameter of the fixing seat matches the inner diameter of the casing head.

[0014] According to some preferred embodiments of the present application, the fixing seat comprises an upper fixing seat and a lower fixing seat, a first sealing member is arranged between the upper fixing seat and the lower fixing seat, and the upper fixing seat and the lower fixing seat are fixedly connected through a fixing member. The first sealing member can be a graphite sealing ring, and the graphite elastic sealing member is fixed between the upper fixing seat and the lower fixing seat through the fixing member. The graphite elastic sealing member expands through pressure deformation to realize sealing with the casing. The inner diameter and the outer diameter of the upper fixing seat and the lower fixing seat correspond to each other, and the inner diameter of the first sealing member is smaller than the inner diameter of the upper fixing seat or the lower fixing seat, and the outer diameter of the first sealing member is larger than the outer diameter of the upper fixing seat or the lower fixing seat, that is, the size of the first sealing member is larger than the size of the upper fixing seat or the lower fixing seat, so as to achieve better sealing and centering effects.

[0015] According to some preferred embodiments of the present application, the insertion groove is an annular groove arranged on the inner wall of the casing head. As long as the slider is completely inserted into the annular insertion groove, the centralizer is installed, the installation is simple, and the centering and sealing effects are good.

[0016] Due to the above technical solutions, compared with the prior art, the geothermal wellhead casing centralizer can effectively seal and center the casing, without needing to open a hole with a penetrating thickness on the four-way cross assembly or the casing head assembly to install a jacking screw, the installation is simple, the cladding design of the centralizing structure can reduce heat loss in the well, and the service life of the components can be effectively prolonged. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0018] Figure 1 FIG. 1 is a structural schematic view of a geothermal wellhead device according to a preferred embodiment of the present application;

[0019] Figure 2 FIG. 2 is a structural schematic view of a geothermal wellhead device according to another preferred embodiment of the present application; Figure 1 FIG. 3 is an enlarged view of the I part in FIG. 2;

[0020] Figure 3 FIG. 4 is an enlarged view of the II part in FIG. 2; Figure 1 FIG. 5 is an enlarged view of the III part in FIG. 2;

[0021] Figure 4The structure schematic view of the slider of the centralizer in the geothermal well head device of the preferred embodiment of the present application is shown when the slider is extended;

[0022] Figure 5 The structure schematic view of the slider of the centralizer in the geothermal well head device of the preferred embodiment of the present application is shown when the slider is retracted;

[0023] Figure 6 The sectional view of the slider of the centralizer of the preferred embodiment of the present application is shown;

[0024] Figure 7 The top view of the slider of the centralizer of the preferred embodiment of the present application is shown;

[0025] Figure 8 The front view of the driving member of the centralizer of the preferred embodiment of the present application is shown;

[0026] In the drawings: guide sleeve assembly-1, sealing assembly-2, four-way assembly-3, centralizer-4, casing head assembly-5, slider-6, tooth groove-61, insertion inclined surface-62, limiting portion-63, limiting groove-631, elastic member-7, driving member-9, connecting portion-91, threaded portion-92, gear portion-93, accommodating groove-10, upper fixing seat-111, first sealing member-112, lower fixing seat-113, fixing member-12, insertion groove-13, upper sealing seat-14, second sealing member-15, middle sealing seat-16, third sealing member-17, lower sealing seat-18, extrusion surface-20, centralizing ring-21, through hole-22, test hole-23, positioning surface-24, body-25, extension-26, guide inclined surface-27, casing-28, welding point-29. DETAILED DESCRIPTION

[0027] In order to make the personnel in the technical field better understand the present application scheme, the technical scheme in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by the person of ordinary skill in the art without creative labor should belong to the protection scope of the present application.

[0028] As Figures 1-8As shown, the geothermal wellhead device of this embodiment includes a casing head assembly 5, a four-way assembly 3 fixedly connected to the casing head assembly 5, a casing 28 disposed within the casing head assembly 5 and the four-way assembly 3, a centralizer 4 and a sealing assembly 2 disposed between the casing 28 and the casing head assembly 5, and a guide sleeve assembly 1 disposed at the top of the casing 28. The sealing assembly 2 is disposed above the centralizer 4. Both the elastic sealing assembly 2 and the centralizer 4 serve to centralize and seal the casing 28; the guide sleeve assembly 1 guides the drill bit to prevent collision between the drill bit and the casing 28 during drilling. The structure of each component is described in detail below:

[0029] 1. Centralizer 4

[0030] like Figure 1 and 4 As shown in Figure -8, the centralizer 4 includes a fixed base and centralizing mechanisms disposed on the fixed base. Preferably, four centralizing mechanisms are evenly spaced and distributed along the same circumference of the fixed base. In this embodiment, the fixed base includes an upper fixed base 111 and a lower fixed base 113. A first sealing element 112 is disposed between the upper fixed base 111 and the lower fixed base 113, and the upper fixed base 111 and the lower fixed base 113 are fixedly connected by the fixing element 12. That is, in this embodiment, the centralizer 4 includes, from top to bottom, an upper fixed base 111, a first sealing element 112, and a lower fixed base 113. The first sealing element 112 can be a graphite sealing ring. The graphite elastic sealing element is fixed between the upper fixed base 111 and the lower fixed base 113 by the fixing element 12, which can be a bolt or similar component. The graphite elastic sealing element achieves a seal with the sleeve 28 through deformation and expansion under heat and pressure.

[0031] The inner and outer diameters of the upper fixed seat 111 and the lower fixed seat 113 are the same, and the inner diameter of the first sealing element 112 is smaller than the inner diameter of the upper fixed seat 111 or the lower fixed seat 113, while the outer diameter of the first sealing element 112 is larger than the outer diameter of the upper fixed seat 111 or the lower fixed seat 113. That is, the size of the first sealing element 112 is larger than the size of the upper fixed seat 111 or the lower fixed seat 113, so as to achieve better sealing and alignment.

[0032] The righting mechanism comprises a receiving groove 10 formed on the upper fixing seat 111, a sliding block 6 received in the receiving groove 10, an elastic member 7 arranged between the sliding block 6 and the receiving groove 10, and a driving member 9 for driving the sliding block 6 to move relative to the receiving groove 10. An insertion groove 13 corresponding to the receiving groove 10 is formed on the inner wall of the casing head assembly 5, and the insertion groove 13 can be annularly formed on the inner wall of the casing head assembly 5. The driving member 9 is used to drive the sliding block 6 to be inserted into or withdrawn from the insertion groove 13. The receiving groove 10 extends along the radial direction of the annular fixing seat. The length of the sliding block 6 is less than or equal to the depth of the receiving groove 10, and the elastic member 7 is used to provide the sliding block 6 with a tendency to be inserted into the insertion groove 13. That is, the receiving groove 10 is a blind hole formed along the radial direction of the fixing seat, and the opening of the receiving groove 10 faces the inner wall of the casing head assembly 5. The elastic member 7 is preferably a spring, and the arrangement direction and deformation direction of the spring are the same as the arrangement direction of the receiving groove 10. The spring is arranged to avoid driving failure of the sliding block 6 or to balance the pressure of the well medium when the pressure in the well is too large, so as to prevent the sliding block 6 from retreating into the receiving groove 10 of the fixing seat and avoid the righting device 4 being pushed out by the pressure in the well. The annular insertion groove is arranged so that the righting device is installed as long as the sliding block is completely inserted into the annular insertion groove, and the installation is simple, accurate and good in sealing effect.

[0033] The end of the lower surface of the sliding block 6 close to the insertion groove 13 has an insertion inclined surface 62, which is preferably an arc-shaped transition surface. The other surface is a rectangular block perpendicular to each other, which prevents the righting device 4 from falling off. The other end of the sliding block 6 is provided with a limiting portion 63 for limiting the elastic member 7. That is, the sliding block 6 is provided with a single-side overhanging round corner, which avoids the failure of the spline of the sliding block 6 and the extension of the sliding block 6 to achieve installation. The limiting portion 63 is annularly arranged to form a limiting groove 631 for installing and limiting the spring.

[0034] The structure for driving the sliding block 6 to move is as follows: a tooth groove 61 is formed on the sliding block 6, and the driving member 9 comprises a connecting portion 91, a threaded portion 92 and a gear portion 93 from top to bottom. The threaded portion 92 is provided with external threads for threaded connection with the upper fixing seat 111. The gear portion 93 is provided with a gear for engaging with the tooth groove 61. The gear is inserted into the tooth groove 61 for driving the sliding block 6 to move by rotating the driving member 9. That is, the driving portion is in the form of a screw. When the righting device 4 is installed, the sliding block 6 is retreated into the receiving groove 10 of the fixing seat by adjusting the screw. Then, the righting device 4 is installed in the casing head 5. After the righting device 4 is stably positioned in the casing head 5, the sliding block 6 is extended out of the receiving groove 10 of the fixing seat and the end thereof is inserted into the insertion groove 13 by adjusting the screw.

[0035] A toothed groove 61 is formed on the top of the slider 6. A key tooth is provided on one side of the groove 61, arranged horizontally. The width of the groove 61 is greater than the maximum diameter of the spline, allowing the gear part 93 to insert into the groove 61 and engage with the key tooth. Rotating the gear part 93 drives the slider 6 to move. The top of the screw has an internal hexagonal recess for easy adjustment and rotation; the middle has a thread that engages with the positioning hole of the upper fixing seat 111, stabilizing the bottom gear part 93 in the gear groove at the top of the slider 6. The gear part 93 has a spline that engages with the key tooth in the gear groove to drive the slider 6. The height of the spline (gear) on the gear part 93 must be greater than the height of the key tooth in the groove 61 to prevent them from disengaging and failing to achieve the driving effect.

[0036] The inner diameters of the upper fixing seat 111 and the lower fixing seat 113 match the outer diameter of the casing 28, and the outer diameters of the upper fixing seat 111 and the lower fixing seat 113 match the inner diameter of the casing head assembly 5. During actual operation of the geothermal wellhead device, the pressure inside the well drives the casing 28 to move up and down reciprocally. The centralizer 4 serves to centralize, align, and seal the casing 28. Furthermore, in this embodiment, the centralizing structure described above eliminates the need to drill through-thickness holes in the four-way assembly 3 or the casing head assembly 5 to install the set screws; the enveloping centralizing structure design reduces heat loss from the well.

[0037] The lower part of the lower fixing seat 113 has a positioning surface 24 that matches the inner wall of the sleeve head 5. Through the positioning inclined surface on the inner wall of the sleeve head 5 and the positioning surface 24 on the fixing seat, the position of the straightener 4 is fixed inside the sleeve head 5, ensuring the subsequent straightening effect.

[0038] 2. Sealing assembly 2

[0039] like Figure 1 and Figure 2 As shown, the sealing assembly 2 includes, from top to bottom, an upper sealing seat 14, a second sealing element 15, a middle sealing seat 16, a third sealing element 17, and a lower sealing seat 18. Both the second sealing element 15 and the third sealing element 17 include a middle portion and sealing portions located at both ends of the middle portion. The thickness of the sealing portions is greater than the thickness of the middle portion. That is, the middle portion of the second sealing element 15 and the third sealing element 17 is thinner, while the sealing portions at both ends are thicker. This allows the sealing elements to expand outwards on both sides when the sealing seats approach each other to compress the sealing elements, achieving a better sealing effect.

[0040] More specifically, the thickness of the sealing part gradually increases from the side close to the middle part to the side away from the middle part, and the side of the sealing seat close to the sealing part has a pressing surface 20 matched with the sealing part. After the sealing part is heated and pressed, the sealing part realizes sealing with the sleeve 28. That is, from the cross section, the middle part of the second sealing part 15 and the third sealing part 17 is rectangular, the sealing parts on both sides are trapezoidal, the pressing surface 20 is in the form of an inclined surface, and the trapezoidal sealing part is arranged between the pressing inclined surfaces of the two sealing seats. When the distance between the two sealing seats is reduced to press the sealing part, the sealing part extends outward under the action of the pressing inclined surface and under the heat to realize sealing with the sleeve 28.

[0041] The inner wall surface of the upper sealing seat 14, the middle sealing seat 16, and the lower sealing seat 18 is provided with a centralizing ring 21. The centralizing ring 21 is used to centralize the sleeve 28, avoid direct contact between the sleeve 28 and the fixing seat, and reduce the resistance of the sleeve 28 during movement.

[0042] The middle sealing seat 16 in the embodiment is also provided with a through hole 22 penetrating in the radial direction thereof, and the through hole 22 is communicated with a test hole 23 on the four-way component 3. That is, the through hole 22 is connected with the test / test hole 23, and sealing leakage can be detected; and sealing grease can be injected through the test / test hole 23 to achieve emergency sealing effect.

[0043] 3. Guide sleeve assembly 1

[0044] The guide sleeve assembly 1 includes a body 25 and an extension 26 extending from the body 25 to the sleeve 28, the bottom of the body 25 is welded to the sleeve 28 and has a welding point 29, the inner diameter of the extension 26 is the same as the inner diameter of the sleeve 28, and the extension 26 is in contact with the top of the sleeve 28. The guide sleeve assembly 1 is used to avoid collision between the drill bit and the sleeve 28 when the drill bit is lowered into the well, and to guide the drill bit, so the upper part of the guide sleeve assembly 1 is provided with a guide inclined surface 27.

[0045] The body 25 and the inner wall of the four-way component 3 are also provided with a centralizing ring 21, which is preferably a wave-shaped centralizing ring 21, for centralizing the top of the sleeve 28, avoiding direct contact between the guide sleeve assembly 1 and the inner wall of the four-way component 3 of the sleeve head, reducing the adhesion of the sleeve 28 to the well wall and blocking, and reducing the resistance of the sleeve 28 to be lowered.

[0046] By Figure 1It can be seen that the lower part of the centralizer 4 is supported on the inner wall of the casing head 5 through the positioning surface 24 and the positioning slope, and the upper part of the centralizer 4 abuts against the lower part of the sealing assembly 2. The inner wall of the four-way assembly 3 is provided with an inwardly protruding abutting part, and the upper part of the sealing assembly 2 abuts against the abutting part. That is, the centralizer 4 and the sealing assembly 2 are arranged between the positioning slope and the abutting part, the assembly and the extrusion of the sealing element are realized through the respective internal fixing members 12 of the centralizer 4 and the sealing assembly 2, the position positioning and installation effect of the centralizer 4 and the sealing assembly 2 are realized through the positioning slope and the abutting part, and the sealing and centering of the casing are further ensured. The guide sleeve assembly 1 is arranged at the top of the casing 28 and above the sealing assembly 2.

[0047] The following briefly describes the installation and working process of the geothermal wellhead device in the embodiment:

[0048] First, the casing 28 is placed at a set position, and then the centralizer 4 is installed. When installing the centralizer 4, the driving member 9 is first rotated, and the gear part 93 at the lower part of the driving member 9 cooperates with the tooth groove 61 on the sliding block 6 to make the sliding block 6 retract into the accommodating groove 10. Then, the centralizer 4 is installed on the casing 28 and placed in the casing head assembly 5, so that the positioning surface 24 at the lower part of the centralizer 4 abuts against the positioning slope in the casing head 5 to position the installation position of the centralizer 4.

[0049] Then, the driving member 9 is directionally rotated to make the sliding block 6 extend outward and into the insertion groove 13 on the inner wall of the casing head 5, thereby fixing the centralizer 4. When installing, the plurality of centralizing mechanisms are sequentially and gradually operated and finally installed in place, so as to avoid uneven force after one of the centralizing mechanisms is installed in place, thereby causing poor centering effect of the centralizer 4.

[0050] Then, the sealing assembly 2 is installed, the guide sleeve assembly 1 is welded to the top end of the casing 28, and finally the four-way assembly 3 is installed on the casing head assembly 5 to fix the centralizer 4 and the sealing assembly 2.

[0051] After installation, in the use process of the geothermal wellhead device, the sealing elements in the centralizer 4 and the sealing assembly 2 extend outward and realize sealing after being heated and pressed, and the casing 28 realizes centering under the action of the centralizer 4 and the centralizing ring 21.

[0052] The geothermal wellhead device in the embodiment has high installation and sealing reliability, reduces the maintenance frequency and maintenance cost, maximizes the service life of the wellhead device under the condition of meeting the emergency situation, and can install the centralizer 4 before cementing, thereby providing accurate alignment of the production casing 28 during the cementing process. The casing 28 is allowed to reciprocate during the cementing operation, the elastic sealing element is expanded after being heated and pressed, and the sealing effect is achieved. Compared with the installation of the centralizing mechanism by the top screw in the past, the installation is more convenient, manpower and time are saved, and the structure design can reduce heat dissipation.

[0053] The above examples are only for illustrating the technical concept and characteristics of the present application, and the purpose is to enable those skilled in the art to understand the content of the present application and to implement it, and cannot limit the protection scope of the present application. Any equivalent changes or modifications made according to the spirit and essence of the present application shall be covered within the protection scope of the present application.

Claims

1. A geothermal wellhead device, comprising a casing head assembly, a four-way assembly fixedly connected to the casing head assembly, a casing disposed within the casing head assembly and the four-way assembly, and a centralizer disposed between the casing and the casing head assembly, characterized in that: The straightener includes a fixed base and a straightening mechanism disposed on the fixed base. The straightening mechanism includes a receiving groove formed on the fixed base, a slider disposed in the receiving groove, an elastic member disposed between the slider and the receiving groove, and a driving member for driving the slider to move relative to the receiving groove. An insertion groove is formed on the inner wall of the sleeve head assembly corresponding to the receiving groove. The driving member is used to drive the slider to insert into the insertion groove or to withdraw from the insertion groove. The slider has an insertion ramp at one end near the insertion slot, and the corresponding other side is a rectangular block that is perpendicular to each other; the other end of the slider is provided with a limiting part for limiting the elastic element. Multiple straightening mechanisms are evenly spaced and distributed along the same circumference of the fixed base.

2. The geothermal wellhead device according to claim 1, characterized in that: The receiving groove extends radially along the fixed base; the length of the slider is less than or equal to the depth of the receiving groove, and the elastic element is used to provide the slider with a tendency to insert into the insertion groove.

3. The geothermal wellhead device according to claim 1, characterized in that: The slider has a toothed groove. The driving component includes a connecting part, a threaded part, and a gear part in sequence. The threaded part is threadedly connected to the fixed seat. The gear part is provided with a gear for meshing with the toothed groove. The gear is inserted into the toothed groove to drive the slider to move by rotating the driving component.

4. The geothermal wellhead device according to claim 1, characterized in that: The fixing base includes an upper fixing base and a lower fixing base, and a first sealing element is provided between the upper fixing base and the lower fixing base. The upper fixing base and the lower fixing base are fixedly connected by the fixing element.

5. The geothermal wellhead device according to claim 1, characterized in that: The sealing assembly includes, from top to bottom, an upper sealing seat, a second sealing element, a middle sealing seat, a third sealing element, and a lower sealing seat. The second and third sealing elements each include a middle portion and sealing portions located at both ends of the middle portion. The thickness of the sealing portion is greater than the thickness of the middle portion.

6. The geothermal wellhead device according to claim 5, characterized in that: The thickness of the sealing portion gradually increases from the side closer to the middle portion to the side farther away from the middle portion, and the sealing seat has a compression surface that matches the sealing portion on the side closer to the sealing element.

7. The geothermal wellhead device according to claim 5, characterized in that: A straightening ring is provided on the inner wall surface of the upper sealing seat, and / or the middle sealing seat, and / or the lower sealing seat.

8. The geothermal wellhead device according to claim 5, characterized in that: The central sealing seat is also provided with a through hole in its radial direction, which communicates with the test hole on the four-way assembly.

9. The geothermal wellhead device according to claim 1, characterized in that: The top of the sleeve is provided with a guide sleeve assembly, which includes a body and an extension extending from the body to the sleeve. The bottom of the body is fixedly connected to the sleeve, the inner diameter of the extension is the same as the inner diameter of the sleeve, and the extension contacts the top of the sleeve.

Images