Cage sleeve type double-wedge-shaped throttle valve

Abstract

The invention relates to the technical field of oil and gas exploitation, and discloses a cage sleeve type double-wedge-shaped throttling valve which comprises a shell with an inner cavity used for fluid flowing. The valve cover is arranged at the top of the shell and is provided with a mounting channel; the valve seat is arranged in the inner cavity and comprises an outer valve seat and an inner valve seat; the valve element comprises two wedge-shaped surfaces and two cylindrical surfaces which are symmetrically arranged about the central axis, the cylindrical surfaces face the direction in which fluid flows into the inner cavity, and the cylindrical surfaces can be attached to the inner wall of the inner valve seat; one end of the valve rod is connected with the driving device, the other end of the valve rod penetrates through the mounting channel to be connected with the valve element, and the valve rod can be driven by the driving device to drive the valve element to reciprocate in the valve seat in the axial extending direction of the valve rod. By means of the scheme, the throttling valve combines the advantages of a cage sleeve type throttling valve and a wedge-shaped throttling valve, two times of throttling are achieved, and the throttling characteristic of the throttling valve is improved; the valve element is of a double-wedge-shaped structure, the pressure can be controlled more finely, and higher erosion resistance is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of oil and gas exploitation, and particularly to a cage-type double-wedge throttle valve. Background Art

[0002] During the process of oil and gas exploitation, well control throttle valves are usually used on the choke manifold to regulate and control the fluid flow rate, so as to maintain an ideal pressure balance relationship between the wellhead back pressure and the formation pressure, discharge the overflow, and keep the wellbore pressure balanced. The main factors affecting the performance of the throttle valve are the structures of the valve core and the valve seat. Good linear structure, wear resistance, and erosion resistance are important indicators of the throttle valve.

[0003] Currently, throttle valves are classified according to the structures of the valve core and the valve seat, and mainly include: cylindrical throttle valves, needle throttle valves, cage-type throttle valves, orifice plate throttle valves, and wedge throttle valves. Among them, when the cylindrical throttle valve is closed, there is a normally open gap channel, that is, it will not be completely closed, and the linearity is poor, the flow rate adjustment range is small. At the same time, when the valve core of the cylindrical throttle valve is in the extended state and the throttle valve tends to close, due to the lengthening of the unsupported suspended part of the valve core, under the erosion of the high-pressure fluid on the inlet side, resonance is likely to occur downstream, resulting in the problem of the cantilever beam, manifested as the fracture of the valve core; the needle throttle valve mainly has problems of poor linearity and cantilever beam, and the actual throttling effect is poor; the cage-type throttle valve has poor erosion resistance, and the throttle holes and the valve body are severely eroded by the high-pressure fluid; due to the fluid being close to the pipe wall, the orifice plate throttle valve also has the problem of poor erosion resistance; the existing wedge throttle valves are usually single-wedge throttle valves, which have problems of cantilever and unstable flow control.

[0004] Therefore, providing a throttle valve with good throttling characteristics and erosion resistance has become an urgent technical problem to be solved. Summary of the Invention

[0005] The purpose of the present invention is to provide a cage-type double-wedge throttle valve to overcome the problems of poor throttling linearity and weak erosion resistance existing in the prior art.

[0006] In order to achieve the above-mentioned object, the present invention provides a cage-type double wedge throttle valve, comprising a housing, the housing comprising an inner cavity for fluid flow; a valve cover arranged on the top of the housing, the valve cover having a mounting channel; a valve seat arranged in the inner cavity, the valve seat comprising an outer valve seat and an inner valve seat, a plurality of flow holes are distributed on the peripheral wall of the outer valve seat, the outer valve seat is arranged in the inner cavity, the inner valve seat is arranged in the outer valve seat, and is located at the bottom of the outer valve seat and is axially staggered with the flow hole, so that the fluid in the inner cavity The fluid flows through the outer valve seat and the inner valve seat in sequence; a valve core, the valve core includes two wedge-shaped surfaces and two cylindrical surfaces axially symmetrically arranged about the central axis, the cylindrical surfaces face the direction in which the fluid flows into the inner cavity, and the cylindrical surfaces can fit with the inner wall of the inner valve seat; and a valve stem, one end of the valve stem is connected to the driving device, and the other end passes through the installation channel and is connected to the valve core, and the valve stem can drive the valve core to reciprocate in the valve seat along the axial extension direction of the valve stem under the drive of the driving device.

[0007] Preferably, there is a gap between the valve stem and the mounting passage for the fluid in the inner cavity to flow in.

[0008] Preferably, the cage-type double wedge throttle valve provided by the present invention further comprises a guide belt arranged in the installation channel and surrounding the valve stem, wherein the guide belt can protect and straighten the valve stem, and a first annular gap is formed between the guide belt and the valve stem.

[0009] Preferably, a countersunk hole is formed at one end of the installation passage close to the outer valve seat, and the top end of the outer valve seat can extend into the countersunk hole.

[0010] Preferably, a sealing assembly is provided at one end of the installation passage away from the outer valve seat to prevent the fluid from flowing out through the gap between the valve stem and the installation passage.

[0011] Preferably, the sealing assembly comprises a packing seal ring provided in a gap between the valve stem and the mounting channel and a packing pressure cap for pressing the packing seal ring.

[0012] Preferably, a second sealing ring is installed between the packing sealing ring and the packing pressure cap.

[0013] Preferably, the driving device includes an electric drive actuator, a rotating sleeve rotatably connected to the electric drive actuator, a bearing seat sleeved outside the rotating sleeve and threadedly connected to the valve cover, a bearing disposed between the rotating sleeve and the bearing seat, and a lead screw assembly disposed inside the rotating sleeve. The lead screw assembly includes a lead screw and a nut threadedly connected to the lead screw. One end of the lead screw away from the nut is connected to the valve stem. Among them, the electric drive actuator is configured to drive the rotating sleeve to rotate, drive the nut to rotate, so that the lead screw reciprocates along its axial extension direction.

[0014] Preferably, the cage-type double-wedge throttle valve provided by the present invention further includes an anti-rotation pin, and the anti-rotation pin passes through the bearing seat and abuts against the valve cover.

[0015] Preferably, the cage-type double-wedge throttle valve provided by the present invention further includes a limit pin. One end of the limit pin abuts in a keyway on the valve stem, and the other end is fixedly connected to the installation channel. The fluid in the inner cavity can flow into the gap between the valve stem and the installation channel through the keyway.

[0016] Preferably, the inner cavity includes a fluid cavity axially extending and connected to the bottom of the installation channel, a fluid inlet channel radially extending and connected to one side of the fluid cavity, and a fluid outlet channel axially extending and connected to the bottom of the fluid cavity. Among them, the diameter of the fluid cavity is larger than the diameters of the installation channel, the fluid inlet channel, and the fluid outlet channel, and the lower end of the valve seat is partially inserted into the fluid outlet channel.

[0017] Preferably, the cage-type double-wedge throttle valve provided by the present invention further includes a protective sleeve disposed in the fluid outlet channel, and the upper end of the protective sleeve is joined to the lower end of the valve seat.

[0018] Preferably, a first sealing ring is provided between the upper end of the protective sleeve and the lower end of the valve seat.

[0019] Preferably, a seating step is formed in the fluid outlet channel, and the protective sleeve is stopped on the seating step.

[0020] Preferably, the inner cavity further includes a pressure relief outlet channel radially extending and connected to the other side of the fluid cavity, and a pressure relief valve is provided on the side of the pressure relief outlet channel away from the fluid cavity to discharge the pressure in the inner cavity.

[0021] Through the cage-type double-wedge throttle valve provided by the present invention, at least the following beneficial effects can be achieved:

[0022] (1) The valve seat includes an outer valve seat and an inner valve seat. A plurality of flow holes are provided on the circumferential wall of the outer valve seat. When the fluid in the inner cavity flows into the outer valve seat through the flow holes, the flow area of the fluid changes, and the flow velocity inside and outside the outer valve seat changes, realizing primary throttling. The fluid enters the inner cavity and then circumferentially enters the outer valve seat through the flow holes, making the fluid flow evenly and endowing the outer valve seat with good throttling characteristics. By changing the distribution density and hole size of the flow holes on the outer valve seat, the flow velocity of the fluid flowing into the outer valve seat can be adjusted, making the throttling of the outer valve seat have better controllability; the valve core moves with the valve rod and continuously extends into the outer valve seat and the inner valve seat. A flow passage is formed between the wedge surface and the inner valve seat. As the valve core extends downward into the inner valve seat, the flow area of the flow passage between the wedge surface and the inner valve seat gradually decreases, realizing secondary throttling. Compared with the cylindrical structure of a conventional cylindrical throttle valve and the needle-shaped structure of a needle throttle valve, the wedge surface has a longer and larger-inclination-angle guiding surface, making the valve core have a longer throttling stroke and better switching linearity. Through the cooperation of the outer valve seat, the valve core and the valve seat, the present invention can achieve two-stage throttling, integrating the advantages of the outer valve seat having good throttling characteristics, good flow velocity controllability, the valve core having a long throttling stroke and good switching linearity.

[0023] (2) The valve core in the present invention has two wedge surfaces and two cylindrical surfaces symmetrically arranged about the central axis. Compared with the conventional single-wedge structure, on the one hand, the double-wedge structure has better linearity of the throttling opening, improving the accuracy of pressure control inside the throttle valve; on the other hand, the double-wedge is symmetrically arranged, which can balance the pressures on both sides of the wedge surface, enhancing the erosion resistance of the valve core and extending the service life of the valve core.

[0024] (3) During the reciprocating movement of the valve core, the outer valve seat can guide and center the valve core, thus avoiding the problem that the valve core of a conventional single-wedge throttle valve is prone to breakage due to the cantilever structure.

[0025] (4) In the present invention, the cylindrical surface of the valve core faces the direction of the fluid flowing into the inner cavity. At this time, the wedge surface is parallel to the direction of the fluid flowing into the inner cavity, further reducing the erosion of the high-pressure fluid on the wedge surface, and thus extending the service life of the valve core. In addition, the cylindrical surface is in the inner valve seat and can fit with the inner wall of the inner valve seat, enabling the inner valve seat to provide stable support for the valve core, further enhancing the erosion resistance of the valve core and ensuring the stability of the reciprocating movement of the valve core. Description of the Drawings

[0026] Figure 1 is a schematic structural diagram of the cage-type double-wedge throttle valve provided by the present invention;

[0027] Figure 2 is a schematic structural diagram of the screw rod assembly of the cage-type double-wedge throttle valve provided by the present invention;

[0028] Figure 3It is a schematic diagram of the installation of the valve core of the cage-type double-wedge throttle valve provided by the present invention;

[0029] Figure 4 It is a schematic diagram of the counterbore at the lower end of the valve cover of the cage-type double-wedge throttle valve provided by the present invention;

[0030] Figure 5 It is a schematic diagram of the high-pressure fluid flow direction in the cage-type double-wedge throttle valve provided by the present invention;

[0031] Figure 6 It is a schematic diagram of the structure of the outer valve seat of the cage-type double-wedge throttle valve provided by the present invention;

[0032] Figure 7 It is a schematic diagram of the channel of the housing of the cage-type double-wedge throttle valve provided by the present invention;

[0033] Figure 8 It is a schematic diagram of the valve core of the cage-type double-wedge throttle valve provided by the present invention;

[0034] Figure 9 It is a schematic diagram of the valve stem of the cage-type double-wedge throttle valve provided by the present invention;

[0035] Figure 10 It is a schematic diagram of the inner valve seat of the cage-type double-wedge throttle valve provided by the present invention.

[0036] Explanation of reference numerals

[0037] 1 - Electric drive actuator, 2 - First bolt, 3 - Bearing, 4 - Rotating sleeve, 5 - Packing gland, 6 - Anti-rotation pin, 7 - Valve cover, 7a - Counterbore, 8 - Metal gasket ring, 9 - Limit pin, 10 - Guide strip, 11 - Housing, 11a - Fluid chamber, 11b - Fluid inlet channel, 11c - Seating step, 11d - Fluid outlet channel, 11e - Pressure relief outlet channel, 12 - Valve core, 12a - Cylindrical surface, 12b - Wedge surface, 13 - Inner valve seat, 13a - Upper surface of inner valve seat, 14 - Protective sleeve, 15 - First sealing ring, 16 - Outer valve seat, 16a - Outer valve seat thread, 16b - Flow hole, 16c - Mounting hole, 17 - Pressure relief valve, 18 - Packing sealing ring, 19 - Second bolt, 20 - Second sealing ring, 21 - Valve stem, 21a - Keyway, 21b - Lower surface of valve stem, 22 - Bearing seat, 23 - Lead screw assembly, 23a - Nut, 23b - Screw rod, 24 - Third sealing ring. Detailed implementation manners

[0038] The embodiments of the present invention will be further described in detail below in conjunction with the accompanying drawings and examples. The following detailed description of the examples and the drawings are used to exemplarily illustrate the principles of the present invention, but cannot be used to limit the scope of the present invention. The present invention can be implemented in many different forms, not limited to the specific embodiments disclosed herein, but including all technical solutions falling within the scope of the claims.

[0039] In the present invention, unless otherwise stated, the meaning of "a plurality of" is greater than or equal to two; the orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "inner", "outer", "top", "bottom", etc. is 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 cannot be construed as a limitation of the present invention. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0040] In addition, the "first", "second" and similar terms used in the present invention do not denote any order, quantity or importance, but are only used to distinguish different parts. Words such as "comprising" or "including" mean that the elements before this word are covered by the elements listed after this word, and do not exclude the possibility of also covering other elements.

[0041] It should also be noted that in the description of the present invention, unless otherwise clearly defined and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. When it is described that a specific device is located between a first device and a second device, there may or may not be an intermediate device between the specific device and the first device or the second device.

[0042] All terms used in the present invention have the same meaning as understood by those of ordinary skill in the art to which the present invention pertains, unless otherwise specifically defined. It should also be understood that terms defined in a general dictionary, such as those in a general dictionary, should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and should not be interpreted in an idealized or overly formal sense, unless specifically defined as such here.

[0043] Technologies, methods and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods and devices should be regarded as part of the specification.

[0044] In view of the problems of poor throttling linearity and weak erosion resistance of throttle valves in the prior art, the present invention provides a cage-type double-wedge throttle valve.

[0045] Referring to Figure 1 , Figure 6 and Figure 8 , a cage-type double-wedge throttle valve includes: a housing 11, the housing includes an inner cavity for fluid flow; a valve cover 7, the valve cover 7 is provided at the top of the housing 11, and the valve cover 7 has an installation channel; a valve seat, the valve seat is provided in the inner cavity, the valve seat includes an outer valve seat 16 and an inner valve seat 13, a plurality of flow holes 16b are distributed on the peripheral wall of the outer valve seat 16, the outer valve seat 16 is provided in the inner cavity, the inner valve seat 13 is provided in the outer valve seat 16, and is located at the bottom of the outer valve seat 16 and axially staggered from the flow holes 16b, so that the fluid in the inner cavity flows through the outer valve seat 16 and the inner valve seat 13 in sequence; a valve core 12, the valve core 12 includes two wedge-shaped surfaces 12b and two cylindrical surfaces 12a that are axially symmetrically arranged about the central axis, the cylindrical surfaces 12a face the direction in which the fluid flows into the inner cavity, and the cylindrical surfaces 12a can be attached to the inner wall of the inner valve seat 13; and a valve stem 21, one end of the valve stem 21 is connected to the driving device, the other end passes through the installation channel and is connected to the valve core 12, there is a gap for the inner cavity fluid to flow into between the valve stem 21 and the installation channel, and the valve stem 21 can drive the valve core 12 to reciprocate in the valve seat along the axial extension direction of the valve stem 21 under the drive of the driving device.

[0046] Through the cage-type double-wedge throttle valve provided by the present invention, firstly, the valve seat includes an outer valve seat 16 and an inner valve seat 13. On the one hand, a plurality of flow holes 16b are provided on the peripheral wall of the outer valve seat 16. When the fluid in the inner cavity flows into the outer valve seat 16 through the flow holes 16b, the flow area of the fluid changes, and the flow velocity inside and outside the outer valve seat 16 changes, realizing primary throttling. The fluid enters the inner cavity and then circumferentially enters the outer valve seat 16 through the flow holes 16b, making the fluid flow evenly and endowing the outer valve seat 16 with good throttling characteristics. By changing the distribution density and hole size of the flow holes 16b on the outer valve seat 16, the flow velocity of the fluid flowing into the outer valve seat 16 can be adjusted, making the throttling of the outer valve seat 16 have better controllability. On the other hand, the valve core 12 moves along with the valve rod 21 and continuously extends into the outer valve seat 16 and the inner valve seat 13. A flow channel is formed between the wedge surface 12b and the inner valve seat 13. As the valve core 12 extends downward into the inner valve seat 13, the flow area of the flow channel between the wedge surface 12b and the inner valve seat 13 gradually decreases, realizing secondary throttling. Compared with the cylindrical structure of a conventional cylindrical throttle valve and the needle-shaped structure of a needle-shaped throttle valve, the wedge surface 12b has a longer and larger-inclination-angle guiding surface, making the valve core 12 have a longer throttling stroke and better switching linearity. Through the cooperation of the outer valve seat 16, the valve core 12 and the valve seat, the present invention can achieve two-stage throttling, integrating the advantages of the outer valve seat 16 having good throttling characteristics and good controllability, and the valve core 12 having a long throttling stroke and good switching linearity.

[0047] Secondly, the valve core 12 in the present invention has two wedge surfaces 12b and two cylindrical surfaces 12a that are axially symmetrically arranged about the central axis. Compared with the conventional single-wedge structure, on the one hand, the linearity of the throttling opening of the double-wedge structure is better, which is beneficial to improving the accuracy of pressure control inside the throttle valve. On the other hand, the double-wedge is symmetrically arranged, which can balance the impact force of the high-pressure fluid on both sides of the wedge surface, enhancing the erosion resistance of the valve core 12 and extending the service life of the valve core.

[0048] In addition, during the reciprocating movement of the valve core 12, the outer valve seat 16 can guide and straighten the valve core 12, thus avoiding the problem that the valve core of a conventional single-wedge throttle valve is prone to fracture due to the cantilever structure.

[0049] In addition, in a conventional wedge throttle valve, the wedge surface of the valve core usually faces the fluid inflow direction to achieve a guiding effect. However, in the present invention, the cylindrical surface 12a of the valve core 12 faces the direction of the fluid flowing into the inner cavity, and at this time, the wedge surface 12b is parallel to the direction of the fluid flowing into the inner cavity, thereby further reducing the erosion of the high-pressure fluid on the wedge surface 12a, and further extending the service life of the valve core 12. In addition, in the inner valve seat 13, the outer diameter of the cylindrical surface 12a is the same as the inner diameter of the inner valve seat 13, so that the cylindrical surface 12a fits against the inner wall of the inner valve seat 13, enabling the inner valve seat 13 to provide stable support to the valve core 12, further enhancing the erosion resistance of the valve core 12, and ensuring the stability of the reciprocating movement of the valve core 12.

[0050] Preferably, referring to Figure 1 , the valve cover 7 is connected to the threaded hole at the top of the housing 11 by the second bolt 19.

[0051] Further, a metal gasket ring 8 is provided at the connection between the lower end surface of the valve cover 7 and the upper end surface of the top of the housing 11. The metal gasket ring 8 can be used to seal the valve cover 7 and the housing 11 to prevent the fluid in the inner cavity of the housing 11 from flowing out of the housing 11.

[0052] Preferably, there is a gap for the fluid in the inner cavity to flow into between the valve stem 21 and the installation channel. The fluid flowing into the inner cavity further flows into this gap, so that this gap is communicated with the inner cavity, eliminating the pressure difference between this gap and the inner cavity, and further eliminating the stroke pressure difference of the valve stem 21 reciprocating between this gap and the inner cavity, thereby reducing the resistance suffered by the valve stem 21 during the reciprocating movement between this gap and the inner cavity, preventing the valve stem 21 from vibrating greatly during the reciprocating movement, and being beneficial to ensuring the stability of the reciprocating movement of the valve stem 21.

[0053] Preferably, referring to Figure 1 , the cage-type double-wedge throttle valve provided by the present invention further includes a guiding belt 10 disposed in the installation channel and surrounding the valve stem 21. The guiding belt 10 has a certain elasticity, which can guide and correct the reciprocating movement of the valve stem 21. In addition, the guiding belt 10 can also protect the valve stem 21 to prevent the valve stem 21 from being worn by the installation channel.

[0054] Further, a first annular gap is formed between the guiding belt 10 and the valve stem 21, thereby allowing the fluid in the inner cavity to flow into the gap between the installation channel and the valve stem 21 to eliminate the stroke pressure difference of the valve stem 21 reciprocating between this gap and the inner cavity.

[0055] Preferably, referring to Figure 1 and Figure 4, a counterbore 7a is formed at one end of the installation channel close to the outer valve seat 16. The top end of the outer valve seat 16 can extend into the counterbore 7a. Specifically, the inner diameter of the counterbore 7a is equal to the outer diameter of the outer valve seat 16. The depth of the counterbore 7a can be set according to the actual production situation, as long as it can ensure that the valve cover 7 can provide sufficient support for the outer valve seat 16. When high-pressure fluid flows into the inner cavity, at this time, the outer valve seat 16 is equivalent to a cantilever beam, and large displacement and vibration are likely to occur in its upper part. By setting the counterbore 7a, the upper end of the outer valve seat 16 sinks into the valve cover 7, so that the valve cover 7 can effectively support the upper end of the outer valve seat 16, reduce the displacement and vibration of the upper end of the outer valve seat 16, and thus extend the service life of the outer valve seat 16.

[0056] Preferably, a sealing assembly is provided at one end of the installation channel far from the outer valve seat 16. The sealing assembly can seal the gap between the valve stem 21 and the installation channel to prevent the fluid in the inner cavity from flowing out of the valve cover 7 through the gap between the valve stem 21 and the installation channel.

[0057] In some embodiments of the present invention, the sealing assembly can be an O-ring. The gap between the valve stem 21 and the installation channel is sealed by the O-ring.

[0058] Or, preferably, referring to Figure 1 , the sealing assembly includes a packing seal ring 18 provided in the gap between the valve stem 21 and the installation channel and a packing gland 5 for pressing the packing seal ring 18. Among them, the packing seal ring 18 is provided at one end of the installation channel far from the outer valve seat 16, the packing gland 5 is provided on the side of the packing seal ring 18 far from the outer valve seat 16, and the packing gland 5 is connected to the thread above the valve cover 7 in the installation channel. By tightening the packing gland 5, the packing seal ring 18 is compressed to seal the gap between the valve stem 21 and the installation channel, so as to prevent the fluid in the inner cavity from flowing out of the valve cover 7 through the gap between the valve stem 21 and the installation channel.

[0059] Preferably, a second O-ring 20 is provided between the packing seal ring 18 and the packing gland 5, so as to further improve the sealing performance of the gap between the valve stem 21 and the installation channel at one end of the valve cover 7 far from the outer valve seat 16.

[0060] In some embodiments of the present invention, there are various choices for the driving device. For example, the driving device can be a linear motor. The linear motor drives the valve stem 21 to move reciprocally along its axial extension direction, and then drives the valve core 12 to move reciprocally along the axial extension direction of the valve stem 21, changing the fluid flow area of the flow channel between the valve core 12 and the inner valve seat 13 to achieve the purpose of throttling.

[0061] Or, preferably, referring to Figure 1 and Figure 2, the driving device includes an electric drive actuator 1, a rotating sleeve 4 rotatably connected to the electric drive actuator 1, a bearing seat 22 sleeved outside the rotating sleeve and threadedly connected to the valve cover 7, a bearing 3 disposed between the rotating sleeve 4 and the bearing seat 22, and a lead screw assembly 23 disposed inside the rotating sleeve 4. The lead screw assembly 23 includes a lead screw 23b and a nut 23a threadedly connected to the lead screw 23b. One end of the lead screw 23b away from the nut 23a is connected to the valve stem 21.

[0062] Among them, the electric drive actuator 1 is arranged to drive the rotating sleeve 4 to rotate. The electric drive actuator 1 can be a motor or a motor, as long as it can drive the rotating sleeve 4 to rotate. The rotation of the rotating sleeve 4 drives the nut 23a to rotate. Since the nut 23a is threadedly connected to the lead screw 23b, when the rotating sleeve 4 drives the nut 23a to rotate, the lead screw 23b moves reciprocally along its axial extension direction. One end of the lead screw 23b away from the nut 23a is connected to the valve stem 21. Refer to Figure 1 , the bottom end of the lead screw 23b is threadedly connected to the top end of the valve stem 21, and the bottom end of the valve stem 21 can be welded to the top end of the valve core 12. The lead screw 23b, the valve stem 21, and the valve core 12 are coaxially arranged. Therefore, by driving the rotating sleeve 4 to rotate through the electric drive actuator 1, the rotating sleeve 4 drives the nut 23a to rotate together, so that the lead screw 23b threadedly connected to the nut 23a moves linearly along the axial extension direction of the lead screw 23b. By changing the rotation direction of the electric drive actuator, the rotation direction of the rotating sleeve 4 and the nut 23a can be changed, thereby changing the movement direction of the lead screw 23b, so that the lead screw 23b can move reciprocally along its axial extension direction. Furthermore, the lead screw 23b drives the valve stem 21 and the valve core 12 to move reciprocally along the axial extension direction of the lead screw 23b, and finally changes the flow area of the flow passage between the valve core 12 and the inner valve seat 13 to achieve the throttling effect.

[0063] In addition, the top of the bearing seat 22 is threadedly connected to the threaded hole at the bottom of the electric drive actuator 1 through a first bolt 2, so as to connect the top of the bearing seat 22 to the lower end of the electric drive actuator 1, and the bottom of the bearing seat 22 is threadedly connected to the top of the valve cover 7.

[0064] Preferably, grease can be applied between the rotating sleeve 4 and the bearing seat 22 to reduce the rotation resistance of the rotating sleeve 4 and reduce the power consumption of the electric drive actuator 1.

[0065] Furthermore, refer to Figure 1, a third sealing ring 24 is further provided between the rotating sleeve 4 and the bearing seat 22. The third sealing ring 24 is arranged at the upper part between the rotating sleeve 4 and the bearing seat 22, so as to seal the grease between the rotating sleeve 4 and the bearing seat 22 and prevent the grease from overflowing. In addition, the bearing 3 is arranged at the lower part of the rotating sleeve 4. In order to improve the rotation stability of the rotating sleeve 4, the number of bearings 3 can be multiple. For example, two bearings 3 can be arranged at the lower part of the rotating sleeve 4, and the two bearings 3 are arranged in sequence from top to bottom at the lower part of the rotating sleeve 4.

[0066] In addition, the lower end face of the rotating sleeve 4 contacts the packing gland 5, making the whole throttle valve structure compact and occupying less space.

[0067] Preferably, referring to Figure 1 , the cage-type double-wedge throttle valve provided by the present invention further includes an anti-rotation pin 6. Specifically, an anti-rotation pin mounting hole is provided at the bottom of the bearing seat 22, and the anti-rotation pin 6 passes through the anti-rotation pin mounting hole on the bearing seat 22 and abuts against the valve cover 7, so as to prevent the bearing seat 22 from rotating during the rotation of the rotating sleeve 4.

[0068] Preferably, referring to Figure 1 and Figure 9 , a keyway 21a is provided on the valve stem 21. The cage-type double-wedge throttle valve provided by the present invention further includes a limit pin 9. One end of the limit pin 9 abuts in the keyway 21a on the valve stem 21, and the other end can be fixedly connected to the installation channel; alternatively, the other end of the limit pin 9 can pass through the side wall of the installation channel and abut against the housing 11. Through the limit pin 9, it can be prevented that the valve stem 21 rotates during the reciprocating motion, and further prevent the valve core 12 from rotating during the reciprocating motion.

[0069] In addition, by adjusting the extension length of the keyway 21a facing the valve core 12, it is ensured that the fluid in the inner cavity can flow into the keyway 21a and further into the gap between the valve stem 21 and the installation channel, so that this gap communicates with the inner cavity, eliminating the pressure difference between this gap and the inner cavity, and further eliminating the stroke pressure difference of the valve stem 21 reciprocating between this gap and the inner cavity. Thus, the resistance suffered by the valve stem 21 during the reciprocating motion between this gap and the inner cavity is reduced, preventing the valve stem 21 from vibrating greatly during the reciprocating motion, which is beneficial to ensuring the stability of the reciprocating motion of the valve stem 21.

[0070] Alternatively, in some embodiments of the present invention, a fluid channel can be opened in the valve stem 21, so that the fluid in the inner cavity can flow into the gap between the valve stem 21 and the installation channel. For example, the inlet of this fluid channel can be arranged at one end of the valve stem 21 close to the valve core 12, that is, the inlet of the fluid channel is arranged on the lower surface 21b of the valve stem described below, and the outlet can be arranged on the side wall of the part of the valve stem 21 located in the installation channel, so that the fluid in the inner cavity flows into the gap between the valve stem 21 and the installation channel through this fluid channel.

[0071] Preferably, referring to Figure 1 , Figure 3 , Figure 5 and Figure 7 , the inner cavity includes a fluid chamber 11a axially extending and connected to the bottom of the installation passage, a fluid inlet passage 11b radially extending and connected to one side of the fluid chamber 11a, and a fluid outlet passage 11d axially extending and connected to the bottom of the fluid chamber 11a. The lower end of the valve seat is partially inserted into the fluid outlet passage 11d. Among them, the diameter of the fluid chamber 11a is larger than the diameters of the installation passage, the fluid inlet passage 11b, and the fluid outlet passage 11d. The fluid chamber 11a has a larger diameter, which can increase the accommodation volume of the fluid chamber 11a, so that when the valve core 12 is at the fully open position, that is, when the valve core 12 is at the highest point, the flow capacity of the fluid in the fluid chamber 11a is improved, the back pressure of the throttle valve at large displacements is reduced, and the applicable range of the throttle valve is expanded.

[0072] Preferably, referring to Figure 1 , the cage-type double-wedge throttle valve provided by the present invention further includes a protective sleeve 14 arranged in the fluid outlet passage 11d. The upper end of the protective sleeve 14 is joined to the lower end of the valve seat, so that the protective sleeve 14 can cover the inner wall of the housing 11 downstream of the valve seat, preventing the inner wall of the housing 11 from being eroded by the fluid for a long time, effectively protecting the inner wall of the housing 11, and improving the service life of the housing 11. In addition, the protective sleeve 14 is installed in a detachable manner, which is convenient for later replacement.

[0073] Preferably, the protective sleeve 14 can be made of tungsten carbide material, so that the protective sleeve 14 has high wear resistance and erosion resistance, thereby improving the protection performance of the protective sleeve 14 for the inner wall of the housing 11 and extending the service life of the housing 11.

[0074] Referring to Figure 1 , Figure 5 and Figure 6 , the fluid flows into the fluid chamber 11a through the fluid inlet passage 11b. The fluid in the fluid chamber 11a enters the outer valve seat 16 through the flow holes 16b on the outer valve seat 16 to achieve primary throttling. By the reciprocating movement of the valve core 12 along its axial direction, the flow area of the flow passage between the valve core 12 and the inner valve seat 13 is changed, so as to achieve secondary throttling. Finally, the fluid flows out of the throttle valve through the fluid outlet passage 11d.

[0075] In addition, referring to 1 and Figure 6, the valve seat includes an outer valve seat 16 and an inner valve seat 13. The outer valve seat 16 is formed in a tubular shape. The main body part of the outer valve seat 16 is disposed in the fluid chamber 11a, and a third annular gap is formed between the outer valve seat 16 and the fluid chamber 11a. Fluid first flows into the third annular gap from the fluid inlet passage 11b, and then flows into the outer valve seat 16 through the flow hole 16b. The lower end part of the outer valve seat 16 extends into the fluid outlet passage 11d, and the outer diameter of the outer valve seat 16 is the same as the inner diameter of the fluid outlet passage 11d, so that the outer peripheral surface of the lower end part of the outer valve seat 16 can be joined with the inner peripheral surface of the fluid outlet passage 11d, improving the sealing performance between the outer valve seat 16 and the fluid outlet passage 11d.

[0076] Referring to Figure 1 , Figure 5 and Figure 10 , the inner valve seat 13 is formed in a tubular shape. The inner valve seat 13 is disposed inside the outer valve seat 16. The inner valve seat 13 is located at the bottom of the outer valve seat 16 and is axially offset from the flow hole 16b on the outer valve seat 16, preventing the fluid in the fluid chamber 11a from flowing into the outer valve seat 16 through the flow hole 16b due to the inner valve seat 13 blocking the flow hole 16b. The inner diameter of the inner valve seat 13 is the same as the outer diameter of the cylindrical surface 12a of the valve core 12, so that the inner peripheral surface of the inner valve seat 13 can be joined with the outer peripheral surface of the cylindrical surface 12a, thereby providing effective support for the valve core 12. The outer diameter of the inner valve seat 13 is the same as the inner diameter of the bottom of the outer valve seat 16, so that the outer peripheral surface of the inner valve seat 13 can be fitted with the inner peripheral surface of the bottom of the outer valve seat 16, ensuring the sealing performance of the connection between the inner valve seat 13 and the outer valve seat 16.

[0077] Preferably, referring to Figure 6, the outer valve seat 16 includes an outer valve seat thread 16a provided at the bottom of the outer valve seat 16, a flow-through hole 16b provided in the middle of the outer valve seat 16, and a mounting hole 16c provided on the upper end face of the outer valve seat 16. The outer valve seat 16 extends into the fluid outflow passage 11d and is threadedly connected to the thread in the fluid outflow passage 11d through the outer valve seat thread 16a. A plurality of mounting holes 16c are arranged on the upper end face of the outer valve seat 16. The number of mounting holes 16c is preferably 4 and is evenly distributed on the upper end face of the outer valve seat 16. When threadedly connecting the outer valve seat 16 to the housing 11, a mounting rod can be inserted into the mounting hole 16c, and a rotational torque can be provided to the outer valve seat 16 by rotating the mounting rod, thereby driving the outer valve seat 16 to rotate and threadedly mounting the outer valve seat 16 into the housing 11. In addition, the number of the flow-through holes 16b is multiple and is distributed on the wall surface in the middle of the outer valve seat 16. There are various distribution forms of the flow-through holes 16b on the wall surface of the outer valve seat 16. They can be unevenly distributed on the wall surface of the outer valve seat 16. For example, along the extending direction of the wall surface of the outer valve seat 16 from top to bottom, the distribution density of the flow-through holes 16 gradually decreases; or, preferably, the flow-through holes 16b are evenly distributed on the wall surface of the outer valve seat 16. The size of the flow-through holes 16b can gradually decrease along the extending direction of the wall surface of the outer valve seat 16 from top to bottom; or, the sizes of the multiple flow-through holes 16b are the same, and the size of the flow-through holes 16b can be adjusted according to the size of the solid particles carried in the fluid. The shape of the flow-through holes 16b can be circular, oval or square, and is adjusted according to actual production requirements.

[0078] Preferably, referring to Figure 1 , Figure 8 , Figure 9 and Figure 10 , the valve core 12 includes two wedge-shaped surfaces 12b and two cylindrical surfaces 12a. The two wedge-shaped surfaces 12b are axially symmetric with respect to the central axis of the valve core 12, and the two cylindrical surfaces 12a are axially symmetric with respect to the central axis of the valve core 12. The wedge-shaped surface 12b can be a plane, a concave surface or a convex surface. Preferably, a step is provided at the top end of the wedge-shaped surface 12b, that is, at the end of the valve core 12 far from the valve stem 21, so as to further improve the throttling ability of the valve core 12. During the downward movement of the valve core 12, a flow-through channel is formed between the wedge-shaped surface 12b and the inner valve seat 13, and the flow-through area of the flow-through channel between the wedge-shaped surface 12b and the inner valve seat 13 gradually decreases. When the end of the valve stem 21 close to the valve core 12 contacts the inner valve seat 13, specifically, when the lower surface 21b of the valve stem 21 contacts the upper surface 13a of the inner valve seat 13, the flow-through area of the flow-through channel is zero, that is, the fluid cannot flow from the inner valve seat 16 to the inner valve seat 13, and the throttle valve is in a closed state.

[0079] Of course, there are also many other ways to keep the throttle valve in a closed state. For example, the outer diameter of the valve stem 21 is set to be the same as the inner diameter of the inner valve seat 13. When the valve stem 21 extends downward into the inner valve seat 13, at this time, the fluid cannot flow from the inner valve seat 16 to the inner valve seat 13 either, and the throttle valve is in a closed state.

[0080] Preferably, referring to Figure 1 , the lower part of the inner valve seat 13 extends out of the bottom of the outer valve seat 16 and engages with the upper end of the protective sleeve 14. A first sealing ring 15 is provided between the upper end of the protective sleeve 14 and the lower end of the valve seat. Specifically, a second annular gap is formed between the lower end face of the outer valve seat 16, the part of the inner valve seat 13 extending out of the outer valve seat 16, the upper end face of the protective sleeve 14, and the side wall of the fluid outflow channel 11d. By providing the first sealing ring 15 in the second annular gap, the valve seat and the protective sleeve 14 can be sealed more effectively, preventing the fluid from flowing into the second annular gap and eroding the inner wall of the housing 11.

[0081] Preferably, referring to Figure 1 , Figure 5 and Figure 7 , a seating step 11c is formed in the fluid outflow channel 11d. The protective sleeve 14 is stopped on the seating step 11c. A shape matching the seating step is formed on the outer wall of the protective sleeve 14, so that the seating step 11c can provide an upward supporting force for the protective sleeve 14. The inner valve seat 13 can squeeze the protective sleeve 14 downward, so that the protective sleeve 14 can be better fixed in the fluid outflow channel 11d, providing effective protection for the inner wall of the housing 11 downstream of the valve seat. Further, the inner diameter of the protective sleeve 14 is the same as the inner diameter of the inner valve seat 13, so that the flow rate of the fluid is stable when flowing through the inner valve seat 13 and the protective sleeve 14.

[0082] Preferably, referring to Figure 1 and Figure 7 , the inner cavity further includes a pressure relief outlet channel 11e that extends radially and is connected to the other side of the fluid cavity 11a. A pressure relief valve 17 is provided on the side of the pressure relief outlet channel 11e away from the fluid cavity 11a. When the pressure in the inner cavity is too high, the pressure in the inner cavity can be released from the throttle valve by opening the pressure relief valve to prevent safety accidents.

[0083] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited thereto. Within the technical concept scope of the present invention, various simple modifications can be made to the technical solutions of the present invention, including any suitable combination of each specific technical feature. To avoid unnecessary repetition, the present invention will not separately describe various possible combination methods. But these simple modifications and combinations should also be regarded as the content disclosed by the present invention and all fall within the protection scope of the present invention.

Claims

1. A cage-type double-wedge throttle valve, characterized in that, Comprising: A housing (11), the housing including an inner cavity for fluid flow; A valve cover (7), the valve cover (7) being provided at the top of the housing (11), the valve cover (7) having an installation passage; A valve seat, the valve seat being provided in the inner cavity, the valve seat including an outer valve seat (16) and an inner valve seat (13), a plurality of flow holes (16b) being distributed on the peripheral wall of the outer valve seat (16), the outer valve seat (16) being provided in the inner cavity, the inner valve seat (13) being provided in the outer valve seat (16), and being located at the bottom of the outer valve seat (16) and axially offset from the flow holes (16b), so that the fluid in the inner cavity sequentially flows through the outer valve seat (16) and the inner valve seat (13); A valve core (12), the valve core (12) including two wedge-shaped surfaces (12b) and two cylindrical surfaces (12a) symmetrically arranged about the central axis, the cylindrical surfaces (12a) facing the direction in which fluid flows into the inner cavity, and the cylindrical surfaces (12a) being capable of fitting with the inner wall of the inner valve seat (13); and, A valve stem (21), one end of the valve stem (21) being connected to a driving device, and the other end passing through the installation passage and being connected to the valve core (12), the valve stem (21) being capable of driving the valve core (12) to reciprocate in the valve seat along the axial extension direction of the valve stem (21) under the drive of the driving device.

2. The cage-type double-wedge throttle valve according to claim 1, wherein A gap for the fluid in the inner cavity to flow into is provided between the valve stem (21) and the installation passage.

3. The cage-type double-wedge throttle valve according to claim 2, wherein, A guiding belt (10) provided in the installation passage and surrounding the valve stem (21) is further included, the guiding belt (10) being capable of protecting and straightening the valve stem (21), and a first annular gap being formed between the guiding belt (10) and the valve stem (21).

4. The cage-type double-wedge throttle valve according to claim 1, wherein A counterbore (7a) is formed at one end of the installation passage close to the outer valve seat (16), and the top end of the outer valve seat (16) can extend into the counterbore (7a).

5. The cage-type double-wedge throttle valve according to claim 1, wherein, A sealing assembly is provided at one end of the installation passage far from the outer valve seat (16) to prevent fluid from flowing out through the gap between the valve stem (21) and the installation passage.

6. The cage-type double-wedge throttle valve according to claim 5, wherein, The sealing assembly includes a packing seal ring (18) provided in the gap between the valve stem (21) and the installation passage and a packing gland (5) for pressing the packing seal ring (18).

7. The cage-type double-wedge throttle valve according to claim 6, characterized in that, A second seal ring (20) is installed between the packing seal ring (18) and the packing gland (5).

8. The cage-type double-wedge throttle valve according to any one of claims 1-7, characterized in that, The driving device includes an electric drive actuator (1), a rotating sleeve (4) rotatably connected to the electric drive actuator (1), a bearing seat (22) sleeved outside the rotating sleeve and threadedly connected to the valve cover (7), a bearing (3) disposed between the rotating sleeve (4) and the bearing seat (22), and a lead screw assembly (23) disposed inside the rotating sleeve (4). The lead screw assembly (23) includes a lead screw (23b) and a nut (23a) threadedly connected to the lead screw (23b). One end of the lead screw (23b) away from the nut (23a) is connected to the valve stem (21). Wherein, the electric drive actuator (1) is configured to drive the rotating sleeve (4) to rotate, driving the nut (23a) to rotate, so that the lead screw (23b) reciprocates along its axial extension direction.

9. The cage-type double-wedge throttle valve according to claim 8, characterized in that, It further includes an anti-rotation pin (6), and the anti-rotation pin (6) passes through the bearing seat (22) and abuts against the valve cover (7).

10. The cage-type double-wedge throttle valve according to claim 8, characterized in that, It further includes a limit pin (9). One end of the limit pin (9) abuts in a keyway (21a) on the valve stem (21), and the other end is fixedly connected to the installation channel. The fluid in the inner cavity can flow into the gap between the valve stem (21) and the installation channel through the keyway (21a).

11. The cage-type double-wedge throttle valve according to claim 1, characterized in that, The inner cavity includes a fluid cavity (11a) axially extending and connected to the bottom of the installation channel, a fluid inlet channel (11b) radially extending and connected to one side of the fluid cavity (11a), and a fluid outlet channel (11d) axially extending and connected to the bottom of the fluid cavity (11a). Wherein, the diameter of the fluid cavity (11a) is larger than the diameters of the installation channel, the fluid inlet channel (11b), and the fluid outlet channel (11d). The lower end of the valve seat is partially inserted into the fluid outlet channel (11d).

12. The cage-type double-wedge throttle valve according to claim 11, wherein, It further includes a protective sleeve (14) disposed in the fluid outlet channel (11d), and the upper end of the protective sleeve (14) is joined to the lower end of the valve seat.

13. The cage-type double-wedge throttle valve according to claim 12, wherein, A first sealing ring (15) is provided between the upper end of the protective sleeve (14) and the lower end of the valve seat.

14. The cage-type double-wedge throttle valve according to claim 12, wherein A seating step (11c) is formed in the fluid outlet channel (11d), and the protective sleeve (14) is stopped on the seating step (11c).

15. The cage-type double-wedge throttle valve according to claim 11, characterized in that, The inner cavity further includes a pressure relief outlet channel (11e) radially extending and connected to the other side of the fluid cavity (11a). A pressure relief valve (17) is provided on the side of the pressure relief outlet channel (11e) away from the fluid cavity (11a) to discharge the pressure in the inner cavity.

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