A bidirectional seal stop valve

Abstract

A bidirectional sealing stop valve, including valve body, valve cover and the valve rod arranged on the valve cover for driving, further including valve clapper assembly and valve seat, the valve body is provided with the baffle that separates the inner chamber into inlet flow channel and outlet flow channel, the valve seat is fixed on the baffle, and the baffle is reprocessed thread hole or bevel again, for installing detachable valve seat ring, and defining the valve port that is connected with inlet flow channel and outlet flow channel, the valve seat has the first valve seat sealing surface towards inlet flow channel and the second valve seat sealing surface towards outlet flow channel, because the utility model discloses a " integral valve seat plus double sealing surface valve clapper" extremely simple structure, without pilot valve clapper, hydraulic piston and other multistage components, the overall number of parts is reduced, and the function does not reduce, the valve seat ring can be dismantled, and the sealing ring is pre-press fitted, and only ordinary tools are needed during assembly to complete, secondly, the online disassembly maintenance time is obviously reduced, and the defects of " complex structure, difficult processing and assembly" of the prior art are overcome.

Description

Technical Field

[0001] This utility model relates to the technical field of gate valves, specifically to a bidirectional sealing gate valve. Background Technology

[0002] With the increasing demands for fluid control in industrial pipeline systems, gate valves, as key fluid control components, are widely used in petroleum, chemical, power, and automation industries. Traditional gate valves are mostly one-way sealing structures, prone to leakage under reverse pressure, making them unsuitable for bidirectional sealing applications. Therefore, in recent years, various gate valve technologies with bidirectional sealing capabilities have emerged to improve the reliability and safety of valves under complex operating conditions.

[0003] A search revealed a bidirectional sealing gate valve with publication number "CN111946836B". This technical solution integrates a main valve disc, a pilot valve disc, and a valve disc nut with a cavity within a sleeve installed inside the valve seat. The pilot valve disc is driven by the medium pressure guided by a first and second flow orifice, thus achieving bidirectional sealing under two operating conditions. While this structure achieves medium pressure-assisted sealing, its internal structure is complex, involving multiple valve discs and a precision-fitted rotating disc mechanism. This results in high processing difficulty and complex assembly processes, hindering mass production and subsequent maintenance. Furthermore, this structure relies on the medium pressure difference to drive the pilot valve disc. Under low-pressure or small-pressure fluctuation conditions, the sealing response is delayed, affecting sealing reliability and making it difficult to guarantee stable bidirectional sealing performance across the entire operating range.

[0004] A search revealed a hydraulically driven bidirectional sealed axial flow shut-off valve with publication number "CN107842618B". This design employs a hydraulic drive system, using a screw to move a piston, which in turn uses hydraulic fluid to synchronously actuate the left and right piston valve cores, achieving bidirectional sealing and shut-off. Its advantages include easy opening and closing, low flow resistance, and reliable sealing. However, this structure relies on an external hydraulic system for power, requiring an additional hydraulic source and control circuit, increasing overall system cost and installation space requirements, making it unsuitable for applications without a hydraulic power source. Furthermore, the hydraulic fluid carries a risk of leakage; long-term operation can lead to internal leakage due to seal aging, affecting control accuracy and safety. Additionally, while the axial flow design reduces flow resistance, it demands high fluid cleanliness; impurities can easily clog the piston valve core, causing opening and closing failures, limiting its application in harsh working conditions.

[0005] The aforementioned problems indicate that existing bidirectional sealing gate valve technology still has significant shortcomings in terms of structural complexity, drive dependence, operating condition adaptability, and sealing reliability. In particular, it has not yet formed an ideal solution in terms of requiring no external power, simplifying the structure, and ensuring reliable sealing across the entire differential pressure range. Therefore, there is an urgent need for a new gate valve structure that is simple in structure, requires no external drive, and can stably achieve bidirectional sealing under all operating conditions to meet the demands of modern industry for efficient, reliable, and easy-to-maintain fluid control components. Utility Model Content

[0006] The technical problem to be solved by this utility model is to overcome the obvious shortcomings of existing technologies in terms of structural complexity, drive dependence, working condition adaptability and sealing reliability, especially in terms of not having a good solution for not requiring external power, structural simplification and reliable sealing across the entire differential pressure range.

[0007] The technical solution adopted to solve the above technical problems is:

[0008] A bidirectional sealing shut-off valve includes a valve body, a valve cover, and a valve stem disposed on the valve cover for actuation. It also includes a valve disc assembly and a valve seat. The valve body is provided with a partition that divides the inner cavity into an inlet flow channel and an outlet flow channel. The valve seat is fixed to the partition and defines a valve port that communicates the inlet flow channel and the outlet flow channel. The valve seat has a first valve seat sealing surface facing the inlet flow channel and a second valve seat sealing surface facing the outlet flow channel.

[0009] The valve disc assembly is disposed in the valve body and is floatingly connected to the end of the valve stem. The valve disc assembly has a first valve disc sealing surface that mates with the first valve seat sealing surface and a second valve disc sealing surface that mates with the second valve seat sealing surface.

[0010] The valve stem drives the valve disc assembly to reciprocate along its axial direction, so that the first valve disc sealing surface and the second valve disc sealing surface selectively and simultaneously engage or disengage from the first valve seat sealing surface and the second valve seat sealing surface, thereby realizing the closing or opening of the valve.

[0011] As a preferred embodiment of this utility model, the floating connection between the valve disc assembly and the end of the valve stem is a ball joint connection structure, the end of the valve stem is formed into a ball head, and a spherical groove adapted to the ball head is correspondingly provided on the valve disc assembly.

[0012] As a preferred embodiment of the present invention, the valve disc assembly includes a valve disc frame and a first sealing ring and a second sealing ring fixed on the valve disc frame. The spherical groove is formed on the valve disc frame. The end face of the first sealing ring constitutes the first valve disc sealing surface, and the end face of the second sealing ring constitutes the second valve disc sealing surface.

[0013] As a preferred technical solution of this utility model, the valve disc frame is provided with a first mounting groove and a second mounting groove around its axis, and the first sealing ring and the second sealing ring are elastic sealing rings with pre-tightening force, and are respectively installed in the first mounting groove and the second mounting groove.

[0014] As a preferred embodiment of this utility model, the valve seat is a detachable valve seat ring, which is fixed to the partition plate by means of threads or welding, and the first valve seat sealing surface and the second valve seat sealing surface are integrally formed at both ends of the valve seat ring.

[0015] As a preferred embodiment of this utility model, both the first valve seat sealing surface and the second valve seat sealing surface are conical sealing surfaces or planar sealing surfaces symmetrically distributed around the central axis of the valve port.

[0016] As a preferred technical solution of this utility model, the bottom of the valve frame is set with an inward opening, and its outer side wall is arranged with trapezoidal flow ports to control the pressure and impact force generated by the flow of the medium in the opening and closing state.

[0017] The beneficial effects of this utility model are as follows:

[0018] 1. This utility model adopts a minimalist structure of "integrated valve seat plus double sealing surface valve disc", which eliminates the need for pilot valve disc, hydraulic piston and other multi-stage components. The number of parts is reduced but the function is not reduced. The valve seat ring is detachable and the sealing ring is pre-pressed in. Assembly can be completed with only ordinary tools. In addition, the time for online disassembly and maintenance in the later stage is significantly reduced, which significantly overcomes the defects of "complex structure and difficult processing and assembly" of the existing technology.

[0019] 2. The ball head at the end of the valve stem and the spherical groove of the valve disc form a universal floating connection, which can self-align within a range of ±3°, ensuring that the first and second sealing surfaces are always evenly fitted under bidirectional pressure difference. With the help of the pre-tightened elastic sealing ring, zero leakage is achieved in the full pressure difference range from vacuum to 42MPa and the full temperature range of -196℃ to 650℃. The valve does not rely on external hydraulic pressure or medium pressure difference for drive, and the opening and closing response is fast, meeting the emergency shut-off requirement of ≤2s. This completely solves the reliability problem of "sealing lag under low pressure conditions and external leakage of hydraulic system" in the existing technology. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the main cross-sectional structure of the present utility model;

[0021] Figure 2 This is a schematic diagram of the internal structure of the valve disc holder of this utility model;

[0022] Figure 3 This is a schematic diagram of the main structure of this utility model.

[0023] In the diagram: 1. Valve body; 2. Valve cover; 3. Valve stem; 4. Valve seat; 5. Inlet flow channel; 6. Outlet flow channel; 7. Baffle; 8. First valve seat sealing surface; 9. Second valve seat sealing surface; 10. First valve disc sealing surface; 11. Second valve disc sealing surface; 12. Valve disc bracket; 13. Flow port. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0025] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0026] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0027] In the above description of this utility model, it should be noted that the terms "one side," "the other side," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the utility model product is in use. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first," "second," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0028] Furthermore, terms such as "identical" do not imply that components must be absolutely identical; minor differences are permissible. The term "perpendicular" simply means that the positional relationship between components is more perpendicular than "parallel," not that the structure must be perfectly perpendicular; a slight tilt is acceptable.

[0029] Example 1

[0030] exist Figures 1-3In this invention, a technical solution is provided: a bidirectional sealing stop valve, including a valve body 1, a valve cover 2, and a valve stem 3 disposed on the valve cover 2 for driving, and also including a valve disc assembly and a valve seat 4. The valve body 1 is provided with a partition 7 that divides the inner cavity into an inlet flow channel 5 and an outlet flow channel 6. The valve seat 4 is fixed on the partition 7. At the same time, the partition 7 is further machined with threaded holes or bevels for installing a detachable valve seat ring 4 and defining the valve port that connects the inlet flow channel and the outlet flow channel. The valve seat 4 has a first valve seat sealing surface 8 facing the inlet flow channel 5 and a second valve seat sealing surface 9 facing the outlet flow channel 6.

[0031] The valve disc assembly is disposed inside the valve body 1 and is floatingly connected to the end of the valve stem 3. The valve disc assembly has a first valve disc sealing surface 10 that cooperates with the first valve seat sealing surface 8 and a second valve disc sealing surface 11 that cooperates with the second valve seat sealing surface 9.

[0032] The valve stem 3 drives the valve disc assembly to reciprocate along its axial direction, so that the first valve disc sealing surface 10 and the second valve disc sealing surface 11 selectively and simultaneously engage with or disengage from the first valve seat sealing surface 8 and the second valve seat sealing surface 9, thereby realizing the closing or opening of the valve.

[0033] In one aspect of this embodiment, the floating connection between the valve disc assembly and the end of the valve stem 3 is a ball joint connection structure, the end of the valve stem 3 is formed into a ball, and a spherical groove adapted to the ball is correspondingly provided on the valve disc assembly.

[0034] In one aspect of this embodiment, the valve disc assembly includes a valve disc frame 12 and a first sealing ring and a second sealing ring fixed on the valve disc frame. A spherical groove is formed on the valve disc frame. The end face of the first sealing ring forms a first valve disc sealing surface 10, and the end face of the second sealing ring forms a second valve disc sealing surface 11. A first mounting groove and a second mounting groove are formed around the valve disc frame 12 along its axis. The first sealing ring and the second sealing ring are elastic sealing rings with pre-tightening force, and are respectively installed in the first mounting groove and the second mounting groove.

[0035] In one aspect of this embodiment, the valve seat 4 is a detachable valve seat ring. The valve seat ring is made of corrosion-resistant alloy bar material, and tapered sealing surfaces are machined at both ends simultaneously to improve the sealing effect. The valve seat ring is fixed to the partition plate 7 by thread or welding. The first valve seat sealing surface 8 and the second valve seat sealing surface 9 are integrally formed at both ends of the valve seat ring. Both the first valve seat sealing surface 8 and the second valve seat sealing surface 9 are tapered sealing surfaces or planar sealing surfaces symmetrically distributed around the central axis of the valve port.

[0036] In one aspect of this embodiment, the bottom of the valve frame 12 is open inward, and a trapezoidal flow port 13 is arranged circumferentially on its outer side wall. By first machining the shape of the valve frame 12 and then milling out the trapezoidal flow port 13, the pressure and impact force generated by the flow of the medium in the opening and closing state can be controlled and reduced, so that the flowing liquid gradually enters and exits through the valve port, thereby improving the service life of the equipment.

[0037] The working principle of this utility model is as follows: This utility model uses the valve body 1 as the base material, first forging or casting and then CNC machining to form the inner cavity and partition 7; the valve port is precision bored at the center of the partition 7, and then the detachable valve seat 4 is fixed to the partition 7 by threads or welding, so that the first valve seat sealing surface 8 and the second valve seat sealing surface 9 are symmetrically formed at both ends of the valve port; the valve disc frame 12 is integrally machined, and the outer circle has a first mounting groove and a second mounting groove, into which pre-tightened elastic sealing rings are pressed to form the first valve disc sealing surface 10 and the second valve disc sealing surface 11; a spherical groove is machined on the top of the frame, which connects with the valve stem 3. The ball head at the end forms a floating connection. The valve cover 2 is bolted to the valve body 1. The valve stem 3 passes through the center hole of the valve cover 2. After the ball head is embedded in the groove, it is axially limited by the retaining ring. After assembly, the valve stem 3 is driven by the handwheel or actuator to drive the valve disc assembly to reciprocate along the axis: When moving downward, the first valve disc sealing surface 10 and the second valve disc sealing surface 11 simultaneously fit the first valve seat sealing surface 8 and the second valve seat sealing surface 9 to achieve bidirectional zero-leakage closure; when moving upward, the two sealing surfaces disengage synchronously, and the medium is diverted through the trapezoidal flow port 13 at the bottom of the valve disc frame 12 to reduce water hammer and noise, and complete the opening and closing cycle.

[0038] The contents not described in detail in this specification are existing technologies known to those skilled in the art.

[0039] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model and are not intended to limit it. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this utility model without departing from the spirit and scope of the technical solutions of this utility model, and all such modifications or substitutions should be covered within the scope of the claims of this utility model.

Claims

1. A bidirectional sealing shut-off valve, comprising a valve body (1), a valve cover (2), and a valve stem (3) disposed on the valve cover (2) for actuation, characterized in that: It also includes a valve disc assembly and a valve seat (4). The valve body (1) is provided with a partition (7) that divides the inner cavity into an inlet flow channel (5) and an outlet flow channel (6). The valve seat (4) is fixed on the partition (7) and defines a valve port that connects the inlet flow channel and the outlet flow channel. The valve seat (4) has a first valve seat sealing surface (8) facing the inlet flow channel (5) and a second valve seat sealing surface (9) facing the outlet flow channel (6). The valve disc assembly is disposed inside the valve body (1) and is floatingly connected to the end of the valve stem (3). The valve disc assembly has a first valve disc sealing surface (10) that cooperates with the first valve seat sealing surface (8) and a second valve disc sealing surface (11) that cooperates with the second valve seat sealing surface (9). The valve stem (3) drives the valve disc assembly to reciprocate along its axial direction, so that the first valve disc sealing surface (10) and the second valve disc sealing surface (11) selectively and simultaneously engage or disengage from the first valve seat sealing surface (8) and the second valve seat sealing surface (9), thereby realizing the closing or opening of the valve.

2. The bidirectional sealing shut-off valve according to claim 1, characterized in that: The floating connection between the valve disc assembly and the end of the valve stem (3) is a ball head connection structure, the end of the valve stem (3) is formed into a ball head, and a spherical groove adapted to the ball head is correspondingly provided on the valve disc assembly.

3. A bidirectional sealing shut-off valve according to claim 2, characterized in that: The valve assembly includes a valve frame (12) and a first sealing ring and a second sealing ring fixed on the valve frame. The spherical groove is formed on the valve frame. The end face of the first sealing ring forms the first valve sealing surface (10), and the end face of the second sealing ring forms the second valve sealing surface (11).

4. A bidirectional sealing shut-off valve according to claim 3, characterized in that: The valve disc holder (12) has a first mounting groove and a second mounting groove around its axis. The first sealing ring and the second sealing ring are elastic sealing rings with pre-tightening force, and are respectively installed in the first mounting groove and the second mounting groove.

5. A bidirectional sealing shut-off valve according to claim 1, characterized in that: The valve seat (4) is a detachable valve seat ring, which is fixed to the partition plate (7) by thread or welding. The first valve seat sealing surface (8) and the second valve seat sealing surface (9) are integrally formed at both ends of the valve seat ring.

6. A bidirectional sealing shut-off valve according to claim 5, characterized in that: Both the first valve seat sealing surface (8) and the second valve seat sealing surface (9) are conical or planar sealing surfaces symmetrically distributed around the central axis of the valve port.

7. A bidirectional sealing shut-off valve according to claim 3, characterized in that: The bottom of the valve frame (12) is set with an inward opening, and its outer side wall is arranged with a trapezoidal flow port (13) to control the pressure and impact force generated by the flow of the medium in the open and closed state.

Images