Nitrogen-sealed tank micro-flow special valve

Abstract

The utility model relates to the technical field of valves, in particular to a nitrogen-sealed tank micro-flow special valve which comprises a valve body, a valve seat, a valve rod and a sealing assembly, the valve body is provided with a valve cavity, a first valve port, a second valve port and a third valve port which are communicated with the valve cavity are formed in the valve body, the first valve port and the second valve port are oppositely arranged, the valve seat is arranged in the second valve port, and the valve rod is arranged in the valve cavity. A through hole communicated with the valve cavity is formed in the valve seat, the valve rod and the first valve port are connected through a sealing assembly, and the valve rod is used for blocking the through hole; the sealing assembly comprises a stuffing box, an upper guide pipe, a lower guide pipe and an isolation pipe, the stuffing box is installed in the first valve port, a connecting hole is formed in the stuffing box, and the upper guide pipe, the lower guide pipe and the isolation pipe are sequentially arranged in the connecting hole of the stuffing box from top to bottom, so that sealing guiding of the valve rod is achieved, and the sealing degree is improved; and free movement of the valve rod is not affected, so that the adjusting precision of the valve is higher, and the flow of the valve body is controlled.

Description

Technical Field

[0001] The utility model relates to the technical field of valves, in particular to a special valve for small flow of nitrogen sealing tanks. Background Art

[0002] A nitrogen sealed tank is a storage tank that uses nitrogen to form a weak positive pressure in a closed gas space to isolate the storage medium from the outside world. Regulating valves have important applications in nitrogen sealed tanks. The main function of a nitrogen sealed tank is to maintain a slight positive pressure in the container to prevent outside air from entering, thereby protecting the quality and properties of the stored material.

[0003] The small flow regulating valve in the prior art uses a valve stem to control the opening and closing degree of the regulating valve and adopts a hard seal structural principle. However, since the micro-flow valve is used to control small flow regulation, the size of the regulating valve parts is relatively small, which increases the difficulty of parts processing. It is easy for the fitting clearance between parts to be too large, resulting in fluid leakage, or the fitting clearance between parts to be too small, resulting in jamming. Utility Model Content

[0004] The technical problem to be solved by the utility model is: in order to overcome the problem in the prior art that a small flow valve is used to control a small flow regulation, and therefore the size of the parts of the regulating valve is relatively small, resulting in increased difficulty in processing the parts, and it is easy for the fitting clearance between the parts to be too large, resulting in fluid leakage, or the fitting clearance between the parts to be too small, resulting in a jamming phenomenon, a special valve for a small flow of a nitrogen sealing tank is provided.

[0005] The utility model solves the technical problem by adopting the following technical solution: a nitrogen sealing tank micro-flow special valve, comprising a valve body, a valve seat, a valve stem and a sealing assembly, wherein the valve body has a valve cavity, and the valve body is provided with a first valve port, a second valve port and a third valve port connected to the valve cavity, the first valve port and the second valve port are arranged oppositely, the valve seat is arranged in the second valve port, a through hole connected to the valve cavity is provided on the valve seat, the valve stem and the first valve port are connected by a sealing assembly, and the valve stem is used to block the through hole;

[0006] The sealing assembly includes a stuffing box, an upper guide tube, a lower guide tube and an isolation tube. The stuffing box is installed in the first valve port. A connecting hole is provided inside the stuffing box. The upper guide tube, the isolation tube and the lower guide tube are arranged in the connecting hole of the stuffing box from top to bottom, and the upper guide tube, the lower guide tube and the isolation tube are arranged around the valve stem. The upper guide tube and the isolation tube, as well as the isolation tube and the lower guide tube are filled with stuffing. The stuffing filled in the stuffing box, the upper guide tube, the lower guide tube and the isolation tube, as well as between the upper guide tube and the isolation tube, as well as between the isolation tube and the lower guide tube, realizes the sealing guidance of the valve stem and improves the sealing degree without affecting the free movement of the valve stem, thereby making the valve adjustment accuracy higher, thereby controlling the valve body flow.

[0007] In order to solve the problem of loose fixation of the stuffing box, a fixing groove is further formed on the inner wall of the first valve port protruding outward, and a fixing block matching the fixing groove is protruding on the outer wall of the stuffing box, and the fixing block is arranged in the fixing groove.

[0008] In order to solve the problem that the stuffing box is not firmly fixed, the special valve further includes a valve cover flange, the valve cover flange and the valve body are fixedly connected, and the bottom surface of the valve cover flange is against the top surface of the fixing block.

[0009] In order to solve the problem that the bottom surface of the lower guide tube lacks support and is easy to fall out, the bottom surface of the connecting hole of the stuffing box further protrudes inward to form a limiting portion, and the top surface of the limiting portion contacts the lower guide tube.

[0010] In order to solve the problem that the top surface of the upper guide tube lacks fixation and is prone to position changes, the sealing assembly further includes an isolation ring, the isolation ring and the stuffing box are fixedly connected, and the bottom surface of the isolation ring is against the top surface of the upper guide tube.

[0011] In order to solve the problem of poor stability of the isolation tube, the sealing assembly further includes a sealing sheet that can be spliced ​​into a ring shape, an accommodating cavity is opened on the inner wall of the isolation tube, the sealing sheet is arranged in the accommodating cavity, and an elastic sheet is arranged between the sealing sheet and the side wall of the accommodating cavity, and the elastic sheet enables the sealing sheet to press against the valve stem.

[0012] In order to solve the problem that the upper guide tube and the isolation ring are difficult to fix, the upper guide tube is further provided with a docking portion at the top, the isolation ring is provided with a docking groove matching the docking portion, and the docking portion is arranged in the docking groove.

[0013] In order to solve the problem that the upper guide tube is easy to fall into the connecting hole during installation, the device further includes a docking portion protruding from the outer peripheral surface of the upper guide tube.

[0014] The beneficial effects of the utility model are as follows: the utility model provides a special valve for a small flow rate of a nitrogen sealed tank, which realizes the sealing guidance of the valve stem and improves the sealing degree through the stuffing box, the upper guide tube, the lower guide tube and the isolation tube, and the stuffing filled between the upper guide tube and the isolation tube and between the isolation tube and the lower guide tube, and does not affect the free movement of the valve stem, thereby making the valve adjustment accuracy higher, thereby controlling the flow of the valve body. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0016] Figure 1 It is a cross-sectional structural schematic diagram of the utility model;

[0017] Figure 2 This utility model Figure 1 A schematic diagram of the enlarged structure at A in the middle;

[0018] Figure 3 This utility model Figure 1 A schematic diagram of the enlarged structure at B in the middle;

[0019] Figure 4 It is a structural schematic diagram of the utility model valve installed on the cylinder.

[0020] In the figure: 1, valve body, 11, valve cavity, 12, first valve port, 121, fixing groove, 13, second valve port, 14, third valve port;

[0021] 2. valve seat, 21. through hole;

[0022] 3. Valve stem;

[0023] 4. Sealing assembly, 41. Stuffing box, 411. Connecting hole, 412. Fixing block, 413. Limiting part, 42. Upper guide tube, 421. Butt joint, 43. Lower guide tube, 44. Isolation tube, 45. Stuffing, 46. Isolation ring, 461. Butt joint groove, 47. Sealing sheet, 48. Elastic sheet;

[0024] 5. Bonnet flange. DETAILED DESCRIPTION

[0025] Now the utility model is further described in detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, which only illustrate the basic structure of the utility model in a schematic manner, and therefore only show the components related to the utility model.

[0026] like Figure 1 It is a structural schematic diagram of the utility model, a special valve for nitrogen sealing tank micro-flow, including a valve body 1, a valve seat 2, a valve stem 3 and a sealing assembly 4, the valve body 1 has a valve cavity 11, the valve body 1 is provided with a first valve port 12, a second valve port 13 and a third valve port 14 connected to the valve cavity 11, the first valve port 12 and the second valve port 13 are arranged oppositely, the valve seat 2 is arranged in the second valve port 13, the valve seat 2 is provided with a through hole 21 connected to the valve cavity 11, a sealing gasket is arranged between the valve seat 2 and the valve body 1, the valve stem 3 and the first valve port 12 are connected through the sealing assembly 4, the valve stem 3 is used to block the through hole 21, and control the degree of connection between the through hole 21 and the valve cavity 11;

[0027] like Figure 2 , Figure 3 As shown, the sealing assembly 4 includes a stuffing box 41, an upper guide tube 42, a lower guide tube 43 and an isolation tube 44. The stuffing box 41 is installed in the first valve port 12. The stuffing box 41 has a connecting hole 411 inside. A fixing groove 121 is protruded outwardly on the inner wall of the first valve port 12. A fixing block 412 matching the fixing groove 121 is protruded on the outer wall of the stuffing box 41. The fixing block 412 is arranged in the fixing groove 121.

[0028] The special valve also includes a valve cover flange 5, which is fixedly connected to the valve body 1, and the bottom surface of the valve cover flange 5 is against the top surface of the fixing block 412. The fixing block 412 is clamped by the valve cover flange 5 and the fixing groove 121. On the one hand, the installation strength of the stuffing box 41 can be improved, and the zigzag structure makes the connection between the stuffing box 41 and the valve body 1 highly sealed to avoid fluid leakage. Furthermore, a sealing gasket is arranged between the fixing block 412 and the fixing groove 121.

[0029] like Figure 2 , Figure 3 As shown, the upper guide tube 42, the lower guide tube 43 and the isolation tube 44 are arranged in sequence from top to bottom in the connecting hole 411 of the stuffing box 41, and the upper guide tube 42, the lower guide tube 43 and the isolation tube 44 are arranged around the valve stem 3. The valve stem 3 can move freely in the upper guide tube 42, the lower guide tube 43 and the isolation tube 44 without affecting the overall sealing degree.

[0030] like Figure 2 , Figure 3 As shown, the sealing assembly 4 includes an isolating ring 46, which is fixedly connected to the stuffing box 41, and the bottom surface of the isolating ring 46 is against the top surface of the upper guide tube 42. The bottom surface of the connecting hole 411 of the stuffing box 41 protrudes inward to form a limiting portion 413, and the top surface of the limiting portion 413 is in contact with the lower guide tube 43. Under the clamping cooperation of the limiting portion 413 and the isolating ring 46, the positions of the upper guide tube 42, the lower guide tube 43 and the isolating tube 44 are fixed to prevent them from slipping due to vibration during use, thereby ensuring their sealing at the valve stem 3.

[0031] The upper guide tube 42 has a docking portion 421 at the top, and the isolation ring 46 has a docking groove 461 matching the docking portion 421. The docking portion 421 is arranged in the docking groove 461 to facilitate docking, so that the isolation ring 46 can support the upper guide tube 42, and the top surface of the docking portion 421 is an inclined surface inclined from top to bottom and outward.

[0032] The docking portion 421 protrudes from the outer circumferential surface of the upper guide tube 42 to prevent it from sliding into the connecting hole 411 , so that a fixed gap exists between the upper guide tube 42 and the isolation ring 46 .

[0033] like Figure 3 As shown, the sealing assembly 4 includes a sealing sheet 47 that can be spliced ​​into a ring shape, a receiving cavity 414 is opened on the inner wall of the isolation tube 44, the sealing sheet 47 is arranged in the receiving cavity 414, and an elastic sheet 48 is arranged between the sealing sheet 47 and the side wall of the receiving cavity 414, the elastic sheet 48 enables the sealing sheet 47 to press against the valve stem 3, reducing the gap between the isolation tube 44 and the valve stem 3, and the sealing sheet 47 is elastically designed and does not affect the free movement of the valve stem 3, thereby increasing the stability of the installation of the isolation tube 44 and ensuring the sealing effect.

[0034] like Figure 1 , Figure 2 As shown, fillers 45 are filled between the upper guide tube 42 and the isolation tube 44 and between the isolation tube 44 and the lower guide tube 43. The fillers 45 may be graphite fillers or polytetrafluoroethylene fillers, etc., and this application does not make any specific limitation on this.

[0035] Based on the above ideal embodiments of the utility model, the relevant staff can make various changes and modifications without deviating from the technical concept of the utility model through the above description. The technical scope of the utility model is not limited to the content of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A special valve for small flow rate of nitrogen sealed tank, characterized in that: The invention comprises a valve body (1), a valve seat (2), a valve stem (3) and a sealing assembly (4), wherein the valve body (1) has a valve cavity (11), the valve body (1) is provided with a first valve port (12), a second valve port (13) and a third valve port (14) which are communicated with the valve cavity (11), the first valve port (12) and the second valve port (13) are arranged opposite to each other, the valve seat (2) is arranged in the second valve port (13), the valve seat (2) is provided with a through hole (21) which is communicated with the valve cavity (11), the valve stem (3) and the first valve port (12) are connected via the sealing assembly (4), and the valve stem (3) is used to block the through hole (21); The sealing assembly (4) comprises a stuffing box (41), an upper guide tube (42), a lower guide tube (43) and an isolation tube (44); the stuffing box (41) is installed in the first valve port (12); a connecting hole (411) is provided inside the stuffing box (41); the upper guide tube (42), the isolation tube (44) and the lower guide tube (43) are arranged in sequence from top to bottom in the connecting hole (411) of the stuffing box (41); the upper guide tube (42), the lower guide tube (43) and the isolation tube (44) are all arranged around the valve stem (3); and a stuffing box (45) is filled between the upper guide tube (42) and the isolation tube (44) and between the isolation tube (44) and the lower guide tube (43).

2. A nitrogen sealed tank micro-flow special valve as claimed in claim 1, characterized in that: A fixing groove (121) is formed on the inner wall of the first valve port (12) protruding outwards, and a fixing block (412) matching the fixing groove (121) is formed on the outer wall of the stuffing box (41), and the fixing block (412) is arranged in the fixing groove (121).

3. A nitrogen sealed tank micro-flow special valve as claimed in claim 2, characterized in that: The special valve further comprises a valve cover flange (5), wherein the valve cover flange (5) is fixedly connected to the valve body (1), and the bottom surface of the valve cover flange (5) abuts against the top surface of the fixing block (412).

4. A nitrogen sealed tank micro-flow special valve as claimed in claim 1, characterized in that: The bottom surface of the connecting hole (411) of the stuffing box (41) protrudes inwards to form a limiting portion (413), and the top surface of the limiting portion (413) is in contact with the lower guide tube (43).

5. A nitrogen sealed tank micro-flow special valve as claimed in claim 1, characterized in that: The sealing assembly (4) comprises an isolating ring (46), the isolating ring (46) and the stuffing box (41) are fixedly connected, and the bottom surface of the isolating ring (46) abuts against the top surface of the upper guide tube (42).

6. A nitrogen sealed tank micro-flow special valve as claimed in claim 5, characterized in that: The top of the upper guide tube (42) is provided with a docking portion (421), the isolation ring (46) is provided with a docking groove (461) matching the docking portion (421), and the docking portion (421) is arranged in the docking groove (461).

7. A nitrogen sealed tank micro-flow special valve as claimed in claim 6, characterized in that: The docking portion (421) protrudes from the outer peripheral surface of the upper guide tube (42).

8. A nitrogen sealed tank micro-flow special valve as claimed in claim 1, characterized in that: The sealing assembly (4) comprises a sealing sheet (47) that can be spliced ​​into a ring shape, a receiving cavity (414) is provided on the inner wall of the isolation tube (44), the sealing sheet (47) is arranged in the receiving cavity (414), and an elastic sheet (48) is arranged between the sealing sheet (47) and the side wall of the receiving cavity (414), the elastic sheet (48) enables the sealing sheet (47) to press against the valve stem (3).

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