Multifunctional anti-scouring one-way throttling block valve

Abstract

The multifunctional anti-scouring one-way throttling block valve comprises a valve body provided with an air inlet, an air outlet and a valve cavity, a lower valve seat is located in the valve cavity in a sealed mode, a valve deck is located right opposite to the lower valve seat in a sealed mode, the lower valve seat and the valve deck are located through an inner step structure and are in interference fit with a throttling valve seat, and a throttling hole is formed in the side portion of the throttling valve seat; a throttling valve element is in dynamic sealing sliding fit in the valve deck in the axial direction, a cut-off valve element is in dynamic sealing sliding fit in the throttling valve element in the axial direction, and the throttling valve element and the cut-off valve element are in linkage through a steel ball. The lower valve seat seals and positions the one-way valve seat, and an inner hole of the one-way valve seat is provided with a sinking table and a one-way valve element capable of elastically blocking the sinking table. The throttling and cutting-off double-element valve element structural design is adopted, independent throttling and cutting-off functions are achieved through the unique structure of the throttling valve seat, sealing is assisted through pipeline pressure, the optimal throttling, cutting-off and one-way effects are achieved, and the sealing performance is good.

Description

Technical Field

[0001] The invention relates to a multifunctional anti-scour one-way throttling cut-off valve, belonging to the technical field of shale gas production equipment. Background Art

[0002] At present, the commonly used throttle valves and cut-off valves are all single-core valves with single functions, which have throttling and cut-off functions respectively. Generally, throttle valves are used for cut-off in addition to throttling, but they can ensure throttling, but their cut-off function is poor and cannot ensure complete sealing.

[0003] For example, patent authorization announcement number CN210050301U is a throttling stop valve for cooling and heating machines. Although the throttling and cut-off functions are realized in the valve body, its overall structure is that the stop valve and the two-way throttling structure are assembled into one as two separate structures, that is, the throttling and cut-off structures are connected in series, which occupies a large space and is complicated to operate.

[0004] In addition, the existing throttling and cut-off valves have poor anti-scouring effects, and the valve core and valve seat outlets are easily worn during the throttling process. Summary of the invention

[0005] In view of the deficiencies in the above-mentioned prior art, the present invention proposes a multifunctional anti-scour one-way throttling cut-off valve, which adopts a throttling and cut-off dual-element valve core structure design. The unique structure of the throttling valve seat realizes independent functions of throttling and cut-off, and the cut-off sealing surface does not participate in throttling. At the same time, it ensures that the downstream pressure is high during gap production and the backflow is automatically cut off. The pipeline pressure is used to assist sealing to achieve the best effects of throttling, cut-off and one-way, and the sealing performance is good.

[0006] In order to achieve the above-mentioned purpose, the technical solution of the present invention is as follows: a multifunctional anti-scour one-way throttling cut-off valve, comprising a valve body with an air inlet and an air outlet, wherein the air inlet and the air outlet intersect with a valve cavity in the valve body, wherein a lower valve seat is sealed and positioned along the position of the air outlet, and a valve cover is sealed and positioned opposite the lower valve seat, wherein the lower valve seat and the valve cover are both positioned with an inner step structure and are interference-fitted with a throttle valve seat, and the throttle valve seat has a plurality of throttling holes on the side thereof that are connected with the air inlet and the axial through hole in the throttle valve seat;

[0007] A throttle valve core is slidably matched with the stepped inner hole of the throttle valve seat in the axial direction in the valve cover for dynamic sealing sliding. The throttle valve core is slidably matched with the stepped inner hole of the throttle valve seat and can abut against the stepped inner step surface of the throttle valve seat; a cut-off valve core is slidably matched with the stepped inner hole of the throttle valve seat in the axial direction in the throttle valve core for dynamic sealing sliding. The end of the cut-off valve core is fixedly connected with an anti-scouring sleeve that can axially slide and fit in the axial through hole of the throttle valve seat, and the other end is fixedly connected with a valve stem that can slide axially with the valve cover, wherein the inner hole of the end of the throttle valve core is threadedly matched with a locking sleeve, the inner hole of the locking sleeve is matched with an inner sleeve, the cut-off valve core passes through the inner sleeve, and an annular groove is provided on the outer periphery of the cut-off valve core, and a plurality of steel ball holes corresponding to the position of the annular groove are provided on the side of the inner sleeve, a steel ball is matched in the annular groove and the steel ball hole, and the steel ball abuts against the inner hole wall of the locking sleeve;

[0008] A first sink is provided at one end of the inner hole of the lock sleeve, and a first spring is axially arranged between the first sink and the inner sleeve. A second sink is provided at the other end of the inner hole of the lock sleeve, and the root of the second sink is a slope structure transitioning to the inner hole thereof. The distance between the side of the second sink and the inner hole wall of the lock sleeve is less than the diameter of the steel ball, and the distance is greater than or equal to the depth of the annular groove.

[0009] A one-way valve seat is sealed and positioned in the inner hole on the other side of the lower valve seat. The inner hole of the one-way valve seat has a sink and a one-way valve core that can elastically seal the sink.

[0010] Furthermore, the valve cover, valve stem, shut-off valve core, inner sleeve, locking sleeve and throttling valve core together form a pressure-assisted sealing cavity, and a pressure-assisted sealing airway leading from the valve cavity to the pressure-assisted sealing cavity is provided on the valve cover.

[0011] Furthermore, a plurality of O-rings are provided between the valve cover and the valve body, and an outer convex ring is provided on the outer circumference of the valve cover, and a union is provided to cooperate with the valve body thread and limit the outer convex ring to the end face of the valve body.

[0012] Furthermore, a limited long groove is axially arranged on the outer side of the valve stem, and a positioning pin is positioned inwardly on the side of the valve cover, the end of the positioning pin is located in the limited long groove, and the positioning pin on the side of the valve cover is located between any two of the O-rings.

[0013] Furthermore, the valve cover has a stepped inner hole, and a combined sealing component that matches the valve stem and a pressure cap that positions the combined sealing component are installed in the stepped inner hole, and the pressure cap is threadedly matched with the valve cover.

[0014] Furthermore, the valve stem end is threadedly fitted with a valve stem nut, which is axially positioned on the inner hole of the valve seat by at least two sets of bearings; the bearing is axially pressed and positioned on the pressure cap by an end cover, and the end cover is fixed to the end of the valve cover by a set screw.

[0015] Furthermore, a hand wheel or an electric actuator which can be used to drive the valve stem to axially feed is fixedly connected to the valve stem nut.

[0016] Furthermore, the end of the lower valve seat is threadedly fitted with a locking nut, which limits the one-way valve seat to the stepped inner hole of the lower valve seat, and the locking nut is positioned with a spring seat, the tail of the one-way valve core is fixedly connected to a core shaft, the core shaft passes through the stepped inner hole of the spring seat, and a one-way valve spring is axially arranged between the stepped inner hole of the spring seat and the one-way valve core, and a sleeve positioned on the one-way valve core is arranged on the outer periphery of the one-way valve spring.

[0017] Furthermore, the core shaft is provided with a one-way valve exhaust port connected from the air outlet to the one-way valve spring position.

[0018] Furthermore, the end surface of the valve stem is fixedly connected with a direction indicating plate via a cross recessed countersunk screw.

[0019] The beneficial effects of the present invention are as follows: through the organic integration of the throttling valve core, the shut-off valve core and the one-way valve core in the valve body, a throttling and shut-off double-element valve core structure is specifically adopted, and the throttling valve seat has a unique structural design so that throttling and shutoff work independently, and the shutoff sealing surface does not participate in throttling, and the one-way valve core and valve seat structure design are combined to ensure that the backflow caused by the high downstream pressure during gap production is automatically cut off, and the pipeline pressure is used to assist sealing to achieve the best effects of throttling, shutoff and one-way, and the sealing is good. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of a manually controlled one-way throttling cut-off valve of the present invention;

[0021] Figure 2 yes Figure 1 Schematic diagram of the structure of the middle gas path control;

[0022] Figure 3 yes Figure 1 The enlarged structure diagram of part A in the middle;

[0023] Figure 4 It is a structural schematic diagram of the electrically-actuated one-way throttling cut-off valve of the present invention;

[0024] Figure 5 yes Figure 1 Schematic diagram of the structure of the middle locking sleeve. DETAILED DESCRIPTION

[0025] The present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0026] A kind of Figure 1-5The multifunctional anti-scouring one-way throttling cut-off valve shown comprises a valve body 13 having an air inlet 44 and an air outlet 45, wherein the air inlet 44 and the air outlet 45 intersect with a valve cavity in the valve body 13, a lower valve seat 15 is sealed and positioned along the position of the air outlet 45 in the valve cavity, a valve cover 11 is sealed and positioned opposite the lower valve seat 15, a throttle valve seat 26 is positioned between the lower valve seat 15 and the valve cover 11 by an inner step structure and interference fit, and a plurality of throttle holes are provided on the side of the throttle valve seat 26 to communicate with the air inlet 44 and the axial through hole 303 in the throttle valve seat 26;

[0027] A throttle valve core 30 is slidably matched in the axial direction of the valve cover 11, and the throttle valve core 30 is slidably matched in the stepped inner hole 301 of the throttle valve seat 26, and can abut against the stepped inner step surface 302 of the throttle valve seat 26; a cut-off valve core 36 is slidably matched in the axial direction of the throttle valve core 30, and the end of the cut-off valve core 36 is fixedly connected to an anti-scouring sleeve 27 that can slidably match the axial through hole 303 of the throttle valve seat 26, and another One end is fixedly connected with a valve stem 2 which can slide axially with the valve cover 11, wherein the inner hole of the end of the throttle valve core 30 is threadedly matched with a lock sleeve 31, the inner hole of the lock sleeve 31 is matched with an inner sleeve 34, the cut-off valve core 36 passes through the inner sleeve 34, and the outer periphery of the cut-off valve core 36 is provided with an annular groove, and the side of the inner sleeve 34 is provided with a plurality of steel ball holes corresponding to the position of the annular groove, and a steel ball 32 is matched in the annular groove and the steel ball hole, and the steel ball 32 abuts against the inner hole wall of the lock sleeve 31;

[0028] A first sink is provided at one end of the inner hole of the lock sleeve 31, and a first spring 33 is axially arranged between the first sink and the inner sleeve 34. A second sink is provided at the other end of the inner hole of the lock sleeve 31, and the root of the second sink is a slope structure 310 transitioning to the inner hole thereof. The distance between the side of the second sink and the inner hole wall of the lock sleeve is less than the diameter of the steel ball 32, and the distance is greater than or equal to the depth of the annular groove.

[0029] A one-way valve seat 16 is sealed and positioned in the inner hole on the other side of the lower valve seat 15 . The inner hole of the one-way valve seat 16 has a sink and a one-way valve core 17 that can elastically seal the sink.

[0030] In this case, the valve body 13 includes a straight-through functional mounting position and a side air inlet 44 position, the air inlet 44 is opposite to the valve cavity, the lower part of the valve cavity is an air outlet channel, and the air outlet channel is a structure with stepped countersunk holes at both ends for positioning the lower valve seat 15; the upper part of the valve cavity is a straight-through hole for positioning the matching valve cover 11.

[0031] The lower valve seat 15 is directly positioned on the stepped trough of the outlet channel through a stepped truncated cone, and multiple lower valve seat sealing rings 14 are arranged between the lower valve seat 15 and the valve body 13 to ensure the air tightness of the lower valve seat 15. A trough is arranged at the end of the inner hole of the lower valve seat 15, and the trough and the throttle valve seat 26 are interference fit to ensure reliable sealing. The inner hole of the throttle valve seat 26 is also designed as an inner trough structure, and a plurality of throttle holes are designed on the inner hole wall. The throttle hole diameter can be designed according to actual conditions. For example, in this case, the throttle hole diameter is designed to be a plurality of different diameters. Figure 1 It can be seen that the stepped inner hole 301 of the throttle valve seat 26 is consistent with the aperture of the lower part of the valve cover 11, and is mainly used for the axial sliding of the throttle valve core 30. The throttling function of the valve is realized by the blocking between the throttle valve core 30 and the throttle hole on the throttle valve seat 26. Here, the throttle valve core 30 and the valve cover 11 are dynamically sealed by the throttle valve core sealing ring 28. At the same time, due to the cooperation between the throttle valve seat 26 and the valve cover 11, the sealing surface of the throttle valve core 30 is not flushed by the fluid during the throttling process.

[0032] The lower part of the cut-off valve core 36 is slidably matched in the throttle valve core 30, and a cut-off valve core sealing ring 29 is arranged between the cut-off valve core 36 and the throttle valve core 30 to ensure the dynamic sealing performance between the two. The anti-scouring sleeve 27 is fixedly connected to the end of the cut-off valve core 36, and the anti-scouring sleeve 27 is slidably matched with the axial through hole 303 of the throttle valve seat 26. A plurality of inner through holes are designed on the outer circle of the anti-scouring sleeve 27 to the inner hole for the circulation of the fluid.

[0033] The upper part of the shut-off valve core 36 is linked to the throttle valve core 30 through the locking sleeve 31, the inner sleeve 34, the first spring 33, and the steel ball 32. The inner sleeve 34 is penetrated by the shut-off valve core 36, and the outer periphery of the inner sleeve 34 is a multi-step ladder shaft, one of which cooperates with the locking sleeve 31 to position the first spring 33, and the other is used to limit the end of the locking sleeve 31.

[0034] When the throttle valve core 30 is fed for throttling, the steel ball 32 is in the annular groove of the shut-off valve core 36, the steel ball hole of the inner sleeve 34, and on the inner hole wall of the locking sleeve 31. Due to the interlocking of the shut-off valve core 36 and the inner sleeve 34 by the steel ball 32, when the first spring 33 is at a critical position during the feeding process, the throttle valve core 30 and the shut-off valve core 36 are fed and moved synchronously. At this time, the sealing surface of the shut-off valve core 36 is hidden in the throttle valve core 30, that is, the throttling fluid cannot flush the sealing surface of the shut-off valve core 36. At the same time, the throttle valve core 30 is protected from flushing by the anti-flush sleeve 27, so that the valve seat sealing surface is not flushed.

[0035] When the throttle valve core 30 moves to the stepped inner step surface 302 of the throttle valve seat 26, full throttling is achieved; the shut-off valve core 36 continues to feed and move, and after the steel ball 32 reaches the inclined surface structure 310, the steel ball 32 will partially enter the second sinking position of the locking sleeve 31 along the inclined surface structure 310. At this time, the steel ball 32 releases the linkage state of the shut-off valve core 36 and the inner sleeve 34. At this time, the shut-off valve core 36 continues to cut off until the sealing surface of the shut-off valve core 36 fits with the sealing surface of the throttle valve core 30 and is completely closed, thereby closing the valve.

[0036] The valve cover 11, the valve stem 2, the cut-off valve core 36, the inner sleeve 34, the lock sleeve 31, and the throttle valve core 30 are enclosed to form a pressure-assisted sealing chamber 42. The valve cover 11 is provided with a pressure-assisted sealing airway 43 from the valve chamber to the pressure-assisted sealing chamber 42. The pressure-assisted sealing airway 43 includes an axial long hole provided on the outer circle of the valve cover 11 and a radial through hole perpendicular to the valve cover 11, which extends into the pressure-assisted sealing chamber 42.

[0037] Several O-rings 37 are fitted between the valve cover 11 and the valve body 13, and an outer convex ring is provided on the outer circumference of the valve cover 11. The union 12 is threadedly fitted with the valve body 13 and the outer convex ring is limited on the end face of the valve body 13. At the same time, a limited long groove is axially provided on the outer side of the valve stem 2, and a positioning pin 35 is positioned inwardly on the side of the valve cover 11. The end of the positioning pin 35 is in the limited long groove, and the positioning pin 35 on the side of the valve cover 11 is located between any two O-rings 37.

[0038] The valve cover 11 has a stepped inner hole, and the stepped inner hole is installed with a combined sealing assembly 10 that matches the valve stem 2, and a pressure cap 9 that positions the combined sealing assembly 10, and the pressure cap 9 is threadedly matched with the valve cover 11. The end of the valve stem 2 is threadedly matched with a valve stem nut 8, and the valve stem nut 8 is axially positioned on the inner hole of the valve seat 11 by at least two sets of bearings 7; the bearings 7 are axially pressed and positioned on the pressure cap 9 through the end cover 6, and the end cover 6 is fixed to the end of the valve cover 11 by a set screw 39. The valve stem nut 8 is fixedly connected with a handwheel 5 or an electric actuator 48 that can be used to drive the valve stem 2 to axially feed, such as Figure 1 and Figure 4 .

[0039] Figure 1 In the embodiment, the hand wheel 5 is positioned on the valve stem 2 through the clamping nut 4 and the second locking nut 3, and is used to drive the valve stem nut 8. Figure 4 In the embodiment, the valve cover 11 is externally positioned with a connecting flange 50, which is fixedly connected to an electric actuator 48 via a hexagon socket bolt 49, and the power actuator end of the electric actuator 48 is power-connected to a valve stem nut 8. In order to facilitate intuitive adjustment of throttling cutoff, a direction indicator plate 40 is fixedly connected to the end face of the valve stem 2 via a cross recessed countersunk screw 41. An upper shield 1 is provided at its end.

[0040] The end of the lower valve seat 15 is threadedly fitted with a locking nut 21, which limits the one-way valve seat 16 to the stepped inner hole of the lower valve seat 15, and the locking nut 21 positions a spring seat 20. The tail of the one-way valve core 17 is fixedly connected to a core shaft 24, and the core shaft 24 passes through the stepped inner hole of the spring seat 20. A one-way valve spring 19 is axially arranged between the stepped inner hole of the spring seat 20 and the one-way valve core 17, and a sheath 18 positioned on the one-way valve core 17 is arranged on the outer periphery of the one-way valve spring 19.

[0041] A one-way valve exhaust port 46 connected to the position of the one-way valve spring 19 by an air outlet 45 is provided on the core shaft 24. Finally, a sewage outlet 47 is also provided at the end of the cut-off valve core 36, and sewage is discharged when the cut-off valve core 36 moves to the sealing surface of the throttle valve seat 26.

[0042] When working:

[0043] The natural gas from upstream enters the main channel of the valve body through the air inlet 44, enters through the throttle hole of the throttle valve seat 26, and changes the channel area through the movement of the throttle valve core 30, thereby playing a throttling role. The throttle valve core 30 and the cut-off valve core 36 move downward at the same time as the throttling, directly and completely throttling. The cut-off valve core 36 releases the restriction on the steel ball 32 and continues to move until the sealing surface of the cut-off valve core 36 fits the sealing surface of the throttle valve core 30, thereby cutting off and closing the valve.

[0044] When the valve is opened, the shut-off valve core 36 moves in the reverse direction, and the anti-scouring sleeve 27 protects the valve seat sealing surface from being scoured during the fluid flow process. The pressure-assisted sealing airway 43 on the valve cover 11 ensures pressure-assisted sealing during shutoff. At this time, the throttling valve core 30 does not move in the reverse direction when the shut-off valve core 36 moves in the reverse direction. When the end face of the shut-off valve core 36 contacts the end face of the inner sleeve 34, the inner sleeve 34 is driven to move, and the steel ball 32 moves synchronously with the steel ball hole on the inner sleeve 34. When it moves to the position of the inclined surface structure 310, the steel ball 32 enters the annular groove of the shut-off valve core 36 due to the inward squeezing force of the inclined surface structure 310. At this time, the throttling valve core 30 and the shut-off valve core 36 move in the reverse direction synchronously to achieve a throttling effect.

[0045] When the incoming air pressure of the upstream air inlet 44 is higher than that of the downstream air outlet 45, the one-way valve core 17 moves under the pressure to open the channel for normal working state. When the incoming air pressure of the upstream air inlet 44 is lower than that of the downstream air outlet 45, the one-way valve core 17 moves to fit the sealing surface of the one-way valve seat 16 to prevent fluid backflow, and a good sealing effect is achieved under the pressure-assisted sealing effect.

[0046] In this case, the throttle valve seat 26, the throttle valve core 30, the check valve seat 16, the check valve core 17 and the anti-scouring sleeve 27 are all made of tungsten carbide; while the cut-off valve core 36, the lock sleeve 31, the inner sleeve 3 and the spring seat 20 are made of martensitic stainless steel. The sealing surface of the cut-off valve core 36 is hardened.

[0047] The technical solutions provided by the embodiments of the present invention are introduced in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the embodiments of the present invention. The description of the above embodiments is only applicable to help understand the principles of the embodiments of the present invention. At the same time, for those skilled in the art, according to the embodiments of the present invention, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A multifunctional anti-scour one-way throttling cut-off valve, comprising a valve body (13) having an air inlet (44) and an air outlet (45), wherein the air inlet (44) and the air outlet (45) intersect with a valve cavity in the valve body (13), characterized in that: The valve cavity is sealed with a lower valve seat (15) along the position of the air outlet (45), and a valve cover (11) is sealed and positioned opposite the lower valve seat (15). The lower valve seat (15) and the valve cover (11) are positioned with an inner step structure and are interference-fitted with a throttle valve seat (26). The side of the throttle valve seat (26) has a plurality of throttle holes that communicate with the air inlet (44) and the axial through hole (303) in the throttle valve seat (26); A throttle valve core (30) is dynamically sealed and slidably matched in the axial direction in the valve cover (11), and the throttle valve core (30) is slidably matched in the stepped inner hole (301) of the throttle valve seat (26) and can abut against the stepped inner step surface (302) of the throttle valve seat (26); a cut-off valve core (36) is dynamically sealed and slidably matched in the axial direction in the throttle valve core (30), and one end of the cut-off valve core (36) is fixedly connected to an anti-scouring sleeve (27) that can axially slide and fit in the axial through hole (303) of the throttle valve seat (26), and the other end is fixedly connected to the throttle valve core (36). A valve stem (2) is provided which can slide axially with the valve cover (11), wherein the inner hole of the end of the throttling valve core (30) is threadedly matched with a locking sleeve (31), the inner hole of the locking sleeve (31) is matched with an inner sleeve (34), the shut-off valve core (36) passes through the inner sleeve (34), and the outer periphery of the shut-off valve core (36) is provided with an annular groove, and the side of the inner sleeve (34) is provided with a plurality of steel ball holes which are opposite to the position of the annular groove, and a steel ball (32) is matched in the annular groove and the steel ball hole, and the steel ball (32) is pressed against the inner hole wall of the locking sleeve (31); A first sinking platform is provided at one end of the inner hole of the locking sleeve (31), and a first spring (33) is axially arranged between the first sinking platform and the inner sleeve (34); a second sinking platform is provided at the other end of the inner hole of the locking sleeve (31), and the root of the second sinking platform is an inclined surface structure (310) transitioning to the inner hole thereof; the distance between the side of the second sinking platform and the inner hole wall of the locking sleeve is less than the diameter of the steel ball (32), and the distance is greater than or equal to the depth of the annular groove; A one-way valve seat (16) is sealed and positioned in the inner hole on the other side of the lower valve seat (15). The inner hole of the one-way valve seat (16) has a sink and a one-way valve core (17) that can elastically seal the sink.

2. According to claim 1, a multifunctional anti-scouring one-way throttling cut-off valve is characterized in that: The valve cover (11), the valve stem (2), the shut-off valve core (36), the inner sleeve (34), the locking sleeve (31), and the throttle valve core (30) together form a pressure-assisted sealing cavity (42), and the valve cover (11) is provided with a pressure-assisted sealing airway (43) leading from the valve cavity to the pressure-assisted sealing cavity (42).

3. According to claim 1, a multifunctional anti-scouring one-way throttling cut-off valve is characterized in that: A plurality of O-rings (37) are provided between the valve cover (11) and the valve body (13), and an outer convex ring is provided on the outer circumference of the valve cover (11). A union (12) is threadedly provided with the valve body (13) and the outer convex ring is limited to the end surface of the valve body (13).

4. According to claim 3, a multifunctional anti-scouring one-way throttling cut-off valve is characterized in that: A limited long groove is axially arranged on the outer side of the valve stem (2), and a positioning pin (35) is positioned inwardly on the side of the valve cover (11). The end of the positioning pin (35) is located in the limited long groove, and the position of the positioning pin (35) on the side of the valve cover (11) is between any two of the O-rings (37).

5. According to claim 1, a multifunctional anti-scouring one-way throttling cut-off valve is characterized in that: The valve cover (11) has a stepped inner hole, in which a combined sealing component (10) matching the valve stem (2) and a pressure cap (9) for positioning the combined sealing component (10) are installed, and the pressure cap (9) is threadedly matched with the valve cover (11).

6. According to claim 5, a multifunctional anti-scouring one-way throttling cut-off valve is characterized in that: The end of the valve stem (2) is threadedly fitted with a valve stem nut (8), and the valve stem nut (8) is axially positioned on the inner hole of the valve seat (11) by at least two sets of bearings (7); the bearing (7) is axially pressed and positioned on the pressure cap (9) by an end cover (6), and the end cover (6) is fixed to the end of the valve cover (11) by a set screw (39).

7. A multifunctional anti-scouring one-way throttling cut-off valve according to claim 6, characterized in that: The valve stem nut (8) is fixedly connected to a hand wheel (5) or an electric actuator (48) which can be used to drive the valve stem (2) to axially advance.

8. According to claim 1, a multifunctional anti-scouring one-way throttling cut-off valve is characterized in that: The end of the lower valve seat (15) is threadedly fitted with a locking nut (21), which limits the one-way valve seat (16) to the stepped inner hole of the lower valve seat (15), and the locking nut (21) is positioned with a spring seat (20). The tail of the one-way valve core (17) is fixedly connected to a core shaft (24), and the core shaft (24) passes through the stepped inner hole of the spring seat (20), and a one-way valve spring (19) is axially arranged between the stepped inner hole of the spring seat (20) and the one-way valve core (17), and a sheath (18) positioned on the one-way valve core (17) is arranged on the outer periphery of the one-way valve spring (19).

9. The multifunctional anti-scouring one-way throttling cut-off valve according to claim 8, characterized in that: The core shaft (24) is provided with a one-way valve exhaust port (46) which is connected from the air outlet (45) to the position of the one-way valve spring (19).

10. The multifunctional anti-scouring one-way throttling cut-off valve according to claim 1, characterized in that: The end surface of the valve stem (2) is fixedly connected to a direction indicating plate (40) via a cross recessed countersunk screw (41).

Images