Needle valve with pressure balance structure

Abstract

The utility model belongs to the technical field of fluid conveying equipment, and particularly relates to a needle valve with a pressure balance structure, which comprises a valve body and a valve rod, one end of the valve body is provided with an inlet runner, the other end of the valve body is provided with an installation cavity, the side wall of the valve body is provided with an outlet runner, a valve cavity is arranged in the valve body, and the valve rod is in threaded connection in the installation cavity. The valve rod comprises a driving valve rod and a sealing valve rod, one end of the sealing valve rod is a sealing section, the other end of the sealing valve rod is a connecting section, the diameter of the sealing section is larger than that of the connecting section, the sealing section is adjacent to the inflow channel, the end face of the sealing section is provided with a first flow channel, and the connecting section penetrates through the sealing plug and forms a gap with the valve body. A second runner is arranged on the side wall of the connecting section. By arranging the balance bin in the valve body, a medium can enter the balance bin, thrust of the medium on the sealing valve rod is converted into pressure on the side wall of the balance bin, the valve rod is not affected by the pressure of the medium, then the opening and closing torque of the needle valve is reduced, and the opening and closing flexibility of the needle valve is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of fluid conveying equipment, in particular to a needle valve with a pressure balancing structure. Background Art

[0002] Figure 1 It is a structural schematic diagram of an existing needle valve, such as Figure 1 As shown, the medium enters the valve body b from the inlet a below. When the needle valve needs to be closed, the sealing valve stem c moves downward. When it is fully closed, the sealing valve stem c is always affected by the medium pressure, which will generate an upward thrust. The needle valve must overcome this force to close. Therefore, the handle needs to provide a larger torque to the sealing valve stem c, which increases the opening and closing torque of the needle valve.

[0003] In view of the above problems, the utility model document proposes a needle valve with a pressure balancing structure. Utility Model Content

[0004] The utility model provides a needle valve with a pressure balance structure, which reduces the opening and closing torque of the needle valve and makes the switch of the needle valve more flexible.

[0005] The utility model provides the following technical solutions:

[0006] A needle valve with a pressure balancing structure comprises a valve body and a valve stem, wherein one end of the valve body is provided with an inlet channel, the other end is provided with a mounting cavity, the side wall is provided with an outlet channel, and the valve body is provided with a valve cavity connected with the inlet channel, the outlet channel and the mounting cavity, the valve stem is threadedly connected in the mounting cavity, a sealing plug is clamped in the mounting cavity, the valve stem comprises a driving valve stem and a sealing valve stem, one end of the sealing valve stem is a sealing section, and the other end is a connecting section, the diameter of the sealing section is larger than the diameter of the connecting section, the sealing section is adjacent to the inlet channel, and the end face of the sealing section is provided with a first flow channel along the length direction of the sealing valve stem, the connecting section passes through the sealing plug, and there is a gap between the sealing plug and the inner wall of the valve body, the gap cooperates with the sealing plug and the sealing section to form a balancing chamber, and the side wall of the connecting section is provided with a second flow channel connecting the first flow channel and the balancing chamber; one end of the driving valve stem is clamped with the end of the connecting section, and the other end is located outside the valve body, and the end is provided with a handle.

[0007] Furthermore, one end of the driving valve stem is connected to the handle, and the other end is provided with a "T"-shaped slot. One end of the sealing valve stem is provided with a first flow channel, and the other end is provided with a block matching the slot. The block is inserted in the slot, so that the sealing valve stem is connected to the driving valve stem.

[0008] Furthermore, a first annular groove is formed on the outer side wall of the sealing plug, and a second annular groove is formed on the inner side wall, and a sealing ring and a retaining ring are provided in both the first annular groove and the second annular groove.

[0009] Furthermore, the installation cavity is threadedly connected with a clamping nut at the end of the valve body, the driving valve stem passes through the clamping nut, and the driving valve stem is threadedly connected to the clamping nut, and the clamping nut presses and fixes the sealing plug in the installation cavity.

[0010] Furthermore, the center axis of the inlet channel, the center axis of the valve cavity, the center axis of the sealing valve stem, the center axis of the driving valve stem, the center axis of the installation cavity and the center axis of the clamping nut are coaxially arranged.

[0011] Furthermore, a mounting clamp is provided inside the valve body, the clamping nut presses the sealing plug onto the mounting clamp, and a sealing gasket is provided between the sealing plug and the mounting clamp.

[0012] Furthermore, a third annular groove is formed on the side wall of the sealing section of the sealing valve stem, and a retaining ring and a sealing ring are also provided in the third annular groove.

[0013] Furthermore, a locking nut is threadedly connected to the outer side wall of the compression nut, and the locking nut abuts against the end surface of the valve body.

[0014] In the utility model, a balancing chamber is arranged in the valve body, and a first flow channel and a second flow channel connected to the balancing chamber are provided on the sealing valve stem, so that the medium can enter the balancing chamber, and the thrust of the medium on the sealing valve stem is converted into pressure on the side wall of the balancing chamber, while the valve stem is not affected by the medium pressure, thereby reducing the opening and closing torque of the needle valve and improving the flexibility of the needle valve switch. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the cross-sectional structure of a needle valve in the prior art.

[0016] Reference numerals:

[0017] a. Inlet channel; b. Valve body; c. Sealing valve stem.

[0018] Figure 2 A schematic cross-sectional view of a needle valve with a pressure balancing structure provided in an embodiment of the utility model;

[0019] Figure 3 A schematic cross-sectional view of a valve body in a needle valve with a pressure balancing structure provided in an embodiment of the utility model;

[0020] Figure 4 A partial cross-sectional structural schematic diagram of a sealing valve stem in a needle valve with a pressure balancing structure provided by an embodiment of the utility model;

[0021] Figure 5 A partial cross-sectional structural schematic diagram of a driving valve stem in a needle valve with a pressure balancing structure provided in an embodiment of the utility model.

[0022] Reference numerals:

[0023] 1. Valve body; 2. Inlet channel; 3. Outlet channel; 4. Valve chamber; 5. Installation chamber; 6. Sealing valve stem; 601. Sealing section; 602. Connecting section; 7. Driving valve stem; 8. Sealing plug; 9. First flow channel; 10. Second flow channel; 11. Balancing chamber; 12. Sealing gasket; 13. Pressing nut; 14. Locking nut; 15. Block; 16. Slot; 17. First annular slot; 18. Second annular slot; 19. Third annular slot; 20. Retaining ring; 21. Sealing ring; 22. Handle; 23. Mounting fixture. DETAILED DESCRIPTION

[0024] The embodiments of the present invention are described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0025] In the description of the embodiments of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms, "connection" and "installation" should be understood in a broad sense. For example, "connection" can be a detachable connection or a non-detachable connection; it can be a direct connection or an indirect connection through an intermediate medium. In addition, "connection" can be a direct connection or an indirect connection through an intermediate medium. Among them, "fixed" means that they are connected to each other and the relative position relationship after connection remains unchanged. The directional terms mentioned in the embodiments of the present utility model, such as "inside", "outside", "top", "bottom", etc., are only reference to the directions of the accompanying drawings. Therefore, the directional terms used are for better and clearer explanation and understanding of the embodiments of the present utility model, 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 understood as a limitation on the embodiments of the present utility model.

[0026] In the embodiments of the present invention, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0027] In the embodiment of the present invention, "and / or" is only a description of the association relationship of the associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0028] References to "one embodiment" or "some embodiments" etc. described in this specification mean that one or more embodiments of the utility model include specific features, structures or characteristics described in conjunction with the embodiment. Therefore, the statements "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. that appear in different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways.

[0029] Example:

[0030] Reference Figure 2 As shown, a needle valve with a pressure balance structure includes a valve body 1 and a valve stem. One end of the valve body 1 is provided with an inlet channel 2, the other end is provided with a mounting cavity 5, and the side wall is provided with an outlet channel 3. The valve body 1 is provided with a valve cavity 4 connected with the inlet channel 2, the outlet channel 3 and the mounting cavity 5. The valve stem is threadedly connected in the mounting cavity 5. A sealing plug 8 is clamped in the mounting cavity 5. The valve stem includes a driving valve stem 7 and a sealing valve stem 6. One end of the sealing valve stem 6 is a sealing section 601, and the other end is a connecting section 602. The diameter of the sealing section 601 is larger than that of the connecting section 60 2 diameter, the sealing section 601 is adjacent to the inlet channel 2, and the end surface of the sealing section 601 is provided with a first flow channel 9 along the length direction of the sealing valve stem 6, the connecting section 602 penetrates the sealing plug 8, and there is a gap between it and the inner wall of the valve body 1, the gap cooperates with the sealing plug 8 and the sealing section 601 to form a balancing chamber 11, and the side wall of the connecting section 602 is provided with a second flow channel 10 connecting the first flow channel 9 and the balancing chamber 11; one end of the driving valve stem 7 is clamped with the end of the connecting section 602, and the other end is located outside the valve body 1, and the end is provided with a handle 22.

[0031] Since the diameter of the connecting section 602 of the sealing valve stem 6 is smaller than the diameter of the sealing section 601, the sealing plug 8 is used to position the sealing valve stem 6 to prevent the sealing valve stem 6 from shaking in the installation cavity 5. At the same time, the sealing plug 8 improves the sealing performance of the balancing chamber 11 to prevent the medium from leaking from the connecting section 602 to drive the valve stem 7. The balancing chamber 11 is connected to the inlet channel 2 through the first flow channel and the second flow channel 10, so that the medium can flow into the balancing chamber 11.

[0032] The handle 22 can be used to rotate the driving valve stem 7, which can drive the sealing valve stem 6 to rotate. The sealing valve stem 6 moves up and down to change the size of the balancing chamber 11, and then the pressure on the end face of the sealing section 601 is balanced through the change of the balancing chamber 11, thereby reducing the torque required for rotating the driving valve stem 7, making the opening and closing of the needle valve more flexible.

[0033] One end of the driving valve stem 7 is connected to the handle 22, and the other end is provided with a "T"-shaped groove 16. One end of the sealing valve stem 6 is provided with a first flow channel 9, and the other end is provided with a block 15 that matches the groove 16. The block 15 is clamped in the groove 16, so that the sealing valve stem 6 is connected to the driving valve stem 7.

[0034] The "T"-shaped slot 16 and the block 15 enable the driving valve stem 7 to drive the sealing valve stem 6 to move up and down when it moves up and down, and the sealing valve stem 6 will not be separated from the driving valve stem 7. During installation, the block 15 is inserted from the side of the slot 16 and then clamped in the installation cavity 5. The block 15 and the slot 16 can only move longitudinally with the driving valve stem 7 and the sealing valve stem 6, but cannot move laterally, thereby ensuring that the block 15 cannot fall off from the slot 16, thereby ensuring the stability of the connection between the driving valve stem 7 and the sealing valve stem 6.

[0035] A first annular groove 1716 is formed on the outer wall of the sealing plug 8 , and a second annular groove 1816 is formed on the inner wall thereof. A sealing ring 21 and a retaining ring 20 are disposed in both the first annular groove 1716 and the second annular groove 1816 .

[0036] By arranging a retaining ring 20 and a sealing ring 21 in the first annular groove 1716 on the outer wall of the sealing plug 8, the sealing between the sealing plug 8 and the inner wall of the valve body 1 is improved. By arranging a retaining ring 20 and a sealing ring 21 in the second annular groove 1816 on the inner wall of the sealing plug 8, the sealing between the sealing valve stem 6 and the sealing plug 8 is improved, thereby improving the sealing of the balancing chamber 11, preventing the medium from leaking out of the balancing chamber 11, and thereby improving the sealing effect of the needle valve.

[0037] The mounting cavity 5 is located at the end of the valve body 1 and is threadedly connected with a clamping nut 13 . The driving valve stem 7 passes through the clamping nut 13 , and the driving valve stem 7 is threadedly connected to the clamping nut 13 . The clamping nut 13 presses and fixes the sealing plug 8 in the mounting cavity 5 .

[0038] The clamping nut 13 is threadedly connected to the side wall of the installation cavity 5 in the valve body 1, and the sealing plug 8 is compressed and positioned by the clamping nut 13. The inner wall of the clamping nut 13 is threadedly connected to the driving valve stem 7, so that the driving screw can move up and down while rotating, thereby driving the sealing screw to move up and down, so that the needle valve can be opened and closed.

[0039] The central axis of the inlet channel 2, the central axis of the valve cavity 4, the central axis of the sealing valve stem 6, the central axis of the driving valve stem 7, the central axis of the installation cavity 5 and the central axis of the clamping nut 13 are coaxially arranged.

[0040] While ensuring the stability of the movement of the sealing valve stem 6 and the driving valve stem 7 in the valve body 1 and preventing positional displacement, it is ensured that when closing the needle valve, the sealing valve stem 6 can accurately move to the position of the inlet channel 2 and close the connection between the inlet channel 2 and the valve chamber 4, thereby closing the needle valve.

[0041] A mounting clamp 23 is provided inside the valve body 1 , and a compression nut 13 presses the sealing plug 8 onto the mounting clamp 23 , and a sealing gasket 12 is provided between the sealing plug 8 and the mounting clamp 23 .

[0042] The installation of the sealing plug 8 is facilitated by the installation card platform 23. The sealing plug 8 is placed on the installation card platform 23 and tightened by the tightening nut 13 to fix the position of the sealing plug 8. Then, the sealing gasket 12 is used to improve the sealing between the sealing plug 8 and the installation card platform 23, so that the medium in the balance chamber 11 leaks from the connection between the sealing plug 8 and the installation card platform 23, thereby ensuring the sealing of the needle valve.

[0043] A third annular groove 1916 is formed on the side wall of the sealing section 601 of the sealing valve stem 6 , and a retaining ring and a sealing ring 21 are also disposed in the third annular groove 1916 .

[0044] A retaining ring and a sealing ring 21 are arranged on the side wall of the sealing valve stem 6 to improve the sealing performance between the sealing valve stem 6 and the inner wall of the valve body 1, and prevent the medium in the balancing chamber 11 from leaking from the gap between the sealing section 601 of the sealing valve stem 6 and the inner wall of the valve body 1. After leaking from here, the medium will flow into the outlet channel 3, causing the needle valve to be unable to be completely closed, thereby affecting the normal use of the needle valve.

[0045] The outer wall of the compression nut 13 is also threadedly connected with a locking nut 14 , and the locking nut 14 abuts against the end surface of the valve body 1 .

[0046] The locking nut 14 is used to lock the compression nut 13 to prevent the compression nut 13 from loosening. If the compression nut 13 is loosened, the sealing plug 8 will become loose on the mounting bracket 23, thereby affecting the sealing of the needle valve and causing leakage of the needle valve. Therefore, after locking the locking nut 14, the stability of the position of the compression nut 13 is further improved to ensure the normal use of the needle valve.

[0047] The block 15 at the end of the sealing valve stem 6 is clamped in the groove 16 at the end of the driving valve stem 7, so that the sealing valve stem 6 and the driving valve stem 7 are spliced ​​to form a valve stem, the sealing plug 8 is clamped on the mounting clamp 23 in the valve body 1, and the sealing gasket 12 is placed between the sealing plug 8 and the mounting clamp 23, and then the clamping nut 13 is screwed on the opening of the mounting cavity 5, so that the clamping nut 13 clamps and fixes the sealing plug 8, and then the valve stem is threadedly connected to the valve body 1 through the inner wall of the clamping nut 13, and then the locking nut 14 is screwed on the outer wall of the clamping nut 13, so that the locking nut 14 locks the clamping nut 13 to prevent the clamping nut 13 from loosening, and finally the handle 22 is installed at the end of the valve stem to complete the assembly of the needle valve.

[0048] When in use, the medium flowing in from the inlet channel 2 passes through the first flow channel 9 and the second flow channel 10 and then enters the balancing chamber 11, so that the pressure of the medium on the end of the sealing valve stem 6 is transferred to the balancing chamber 11, and the side wall of the balancing chamber 11 shares the pressure of the medium, so that the valve stem will not be pushed upward by the medium. Therefore, the movement of the valve stem is not affected by the medium pressure, thereby reducing the torque required for opening and closing the needle valve, making the switch needle valve more flexible.

[0049] In actual use, the threads of the locking nut 14 and the compression nut 13 are set in opposite directions to prevent the compression nut 13 and the locking nut 14 from being loosened at the same time, thereby affecting the normal use of the needle valve.

[0050] The above are only specific implementations of the utility model, but the protection scope of the utility model is not limited to them. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the utility model, which should be included in the protection scope of the utility model; in the absence of conflicts, the embodiments of the utility model and the features in the embodiments can be combined with each other. Therefore, the protection scope of the utility model shall be based on the protection scope of the claims.

Claims

1. A needle valve with a pressure balance structure, comprising a valve body and a valve stem, wherein one end of the valve body is provided with an inlet channel, the other end is provided with a mounting cavity, the side wall is provided with an outlet channel, the valve body is provided with a valve cavity connected with the inlet channel, the outlet channel and the mounting cavity, the valve stem is threadedly connected in the mounting cavity, and is characterized in that: A sealing plug is clamped in the installation cavity, and the valve stem includes a driving valve stem and a sealing valve stem, one end of the sealing valve stem is a sealing section, and the other end is a connecting section, the diameter of the sealing section is larger than the diameter of the connecting section, the sealing section is adjacent to the inlet channel, and the end face of the sealing section is provided with a first flow channel along the length direction of the sealing valve stem, the connecting section passes through the sealing plug, and there is a gap between the connecting section and the inner wall of the valve body, the gap cooperates with the sealing plug and the sealing section to form a balancing chamber, and the side wall of the connecting section is provided with a second flow channel connecting the first flow channel and the balancing chamber; one end of the driving valve stem is clamped with the end of the connecting section, and the other end is located outside the valve body, and a handle is provided at the end.

2. A needle valve with a pressure balance structure according to claim 1, characterized in that: One end of the driving valve stem is connected to the handle, and the other end is provided with a "T"-shaped slot. One end of the sealing valve stem is provided with a first flow channel, and the other end is provided with a clamping block that matches the slot. The clamping block is clamped in the slot, so that the sealing valve stem is connected to the driving valve stem.

3. A needle valve with a pressure balance structure according to claim 2, characterized in that: The outer side wall of the sealing plug is provided with a first annular groove, and the inner side wall is provided with a second annular groove. A sealing ring and a retaining ring are arranged in the first annular groove and the second annular groove.

4. A needle valve with a pressure balance structure according to claim 3, characterized in that: The installation cavity is located at the end of the valve body and is threadedly connected with a clamping nut. The driving valve stem passes through the clamping nut, and the driving valve stem is threadedly connected to the clamping nut. The clamping nut presses and fixes the sealing plug in the installation cavity.

5. A needle valve with a pressure balance structure according to claim 4, characterized in that: The central axis of the inlet channel, the central axis of the valve cavity, the central axis of the sealing valve stem, the central axis of the driving valve stem, the central axis of the installation cavity and the central axis of the clamping nut are coaxially arranged.

6. A needle valve with a pressure balance structure according to claim 5, characterized in that: A mounting clamp is provided inside the valve body, the compression nut presses the sealing plug onto the mounting clamp, and a sealing gasket is provided between the sealing plug and the mounting clamp.

7. The needle valve with a pressure balance structure according to claim 6, characterized in that: A third annular groove is formed on the side wall of the sealing section of the sealing valve stem, and a retaining ring and a sealing ring are also arranged in the third annular groove.

8. The needle valve with a pressure balance structure according to claim 7, characterized in that: The outer side wall of the compression nut is also threadedly connected with a locking nut, and the locking nut abuts against the end surface of the valve body.

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