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CN-122014865-A - Pneumatic piston type double-eccentric high-performance butterfly valve

CN122014865ACN 122014865 ACN122014865 ACN 122014865ACN-122014865-A

Abstract

The invention relates to the technical field of air separation nitrogen production and oxygen production, in particular to a pneumatic piston type double-eccentric high-performance butterfly valve which comprises a valve body, a rotating shaft and a butterfly plate, wherein a valve seat assembly which is driven by air to linearly move along the axial direction of a medium channel of the valve body is further arranged in the valve body, a limiting structure which limits the stroke of a valve seat sealing ring to a sealing position and cancels the back-and-forth alternate movement of the sealing position is arranged between the valve seat assembly and the valve body, a packing cavity is formed between the top of the valve body and the rotating shaft in a matched sealing mode when the sealing position is formed, and a self-tightening packing assembly which is tightly pressed by a packing gland and forms self-tightening seal with the outer wall of the rotating shaft is arranged in the packing cavity. According to the invention, the valve seat assembly is driven by air to axially perform linear motion along the medium channel of the valve body, so that the position of the valve seat assembly is accurately controlled, the friction between the valve seat sealing ring and the butterfly plate sealing surface in the rotating process is avoided, and the service life of the valve seat sealing ring is prolonged. Meanwhile, the high-efficiency, high-precision and safe control of the medium is realized.

Inventors

  • Zhuo Chengkun
  • Zhuo Jiacheng
  • Zhuo Wubi
  • QU WENCAI
  • HONG ZHIJIE
  • LIANG WANLI

Assignees

  • 上海罗杰斯阀门有限公司

Dates

Publication Date
20260512
Application Date
20260310

Claims (10)

  1. 1. The pneumatic piston type double-eccentric high-performance butterfly valve comprises a valve body (1), a rotating shaft (2) and a butterfly plate (3), wherein two ends of the rotating shaft (2) penetrate through the valve body (1) and are rotationally connected with the rotating shaft (2) and the valve body (1), the butterfly plate (3) is fixed on the rotating shaft (2) and is positioned in the valve body (1), and the pneumatic piston type double-eccentric high-performance butterfly valve is characterized in that a valve seat assembly (4) which is driven by air to move linearly along a medium channel (11) of the valve body (1) is further arranged in the valve body (1), one end, close to the butterfly plate (3), of the valve seat assembly (4) is provided with a valve seat sealing ring (41) at least partially protruding out of the valve seat assembly (4), at least part of the valve seat sealing ring (41) is provided with a first inclined surface (411) which is arranged at an angle with the shaft of the medium channel (11), and the butterfly plate (3) is provided with a second inclined surface which is consistent with the inclination direction of the first inclined surface (411), and the valve seat assembly (4) is provided with a valve seat assembly (1) which is driven by air, and the second inclined surface (411) is positioned alternately, and the second inclined surface (411) is in a sealing stroke-limiting structure which is used for sealing the valve seat assembly (1) and the sealing structure is in a reciprocating motion limiting and the sealing structure; A packing cavity is formed between the top of the valve body (1) and the rotating shaft (2), and a self-tightening sealing packing assembly (61) which is tightly pressed by a packing gland (62) and forms self-tightening sealing with the outer wall of the rotating shaft (2) is arranged in the packing cavity.
  2. 2. The pneumatic piston type double-eccentric high-performance butterfly valve according to claim 1, wherein the self-tightening packing assembly (61) comprises at least one group of lip-shaped sealing rings (613) sleeved on the outer wall of the rotating shaft (2) and V-shaped tensioning springs (612), one lip-shaped sealing ring (613) and each V-shaped tensioning spring (612) form a sealing unit (611), the V-shaped tensioning springs (612) are arranged on the inner side wall of an opening of the lip-shaped sealing ring (613), and two outer side walls of the opening of the lip-shaped sealing ring (613) are respectively contacted with the outer wall of the rotating shaft (2) and the side wall of the valve body (1).
  3. 3. A pneumatic piston double eccentric high performance butterfly valve according to claim 2, characterized in that the lip seal ring (613) has a number of protrusions (6131) on the open outer side wall.
  4. 4. A pneumatic piston type double eccentric high performance butterfly valve according to claim 2 or 3, wherein, in the axial direction of the rotating shaft (2), a plurality of sealing monomers (611) are sleeved in the packing cavity, an intermediate annular space (614) is formed between the lip seal ring (613) of one sealing monomer (611) of two adjacent sealing monomers (611) and the V-shaped tensioning spring (612) of the other sealing monomer (611), an inner triangle annular space (615) and an outer triangle annular space (616) are formed between the inner walls of the two adjacent sealing monomers (611) and the packing cavity, and the intermediate annular space (614), the inner triangle annular space (615) and the outer triangle annular space (616) of the two adjacent sealing monomers (611) are distributed in a triangle.
  5. 5. A pneumatic piston double eccentric high performance butterfly valve according to claim 2 or 3, characterized in that a spring fixing groove (6132) profiled to the V-shaped tensioning spring (612) is provided in the inner wall of the lip seal ring (613), and that the V-shaped tensioning spring (612) is fixed to the spring fixing groove (6132) and the inner wall of the V-shaped tensioning spring (612) is flush with the inner wall of the lip seal ring (613).
  6. 6. A pneumatic piston double eccentric high performance butterfly valve according to claim 1, characterized in that a third bevel (42) parallel to the first bevel (411) is provided at the end of the valve seat assembly (4) where the valve seat seal (41) is provided, at least part of the valve seat seal (41) protruding from the third bevel (42).
  7. 7. The pneumatic piston type double-eccentric high-performance butterfly valve according to claim 1, wherein an annular chute (12) communicated with the medium channel (11) is further arranged in the valve body (1), the valve seat assembly (4) is annular and is slidably mounted in the annular chute (12), the limiting structure (5) comprises a limiting groove (51) and an opening limiting ring (52), at least part of the limiting groove (51) is formed in a groove opening outer groove wall (121) of the annular chute (12), the rest part of the limiting groove (51) is formed in the outer wall of the valve seat assembly (4), the opening limiting ring (52) is arranged in the limiting groove (51), and the thickness of the opening limiting ring (52) is smaller than the groove width of the limiting groove (51).
  8. 8. A pneumatic piston type double eccentric high-performance butterfly valve according to claim 7, wherein an outer sealing element (13) is arranged between an outer groove wall (121) of the annular sliding groove (12) and an outer wall of the valve seat assembly (4), an inner sealing element (14) is arranged between an inner groove wall (122) of the annular sliding groove (12) and an inner wall of the valve seat assembly (4), an air filling cavity (15) is formed between a groove bottom of the annular sliding groove (12) far away from the groove opening outer groove wall (121) and the valve seat assembly (4), and a stress area of one end of the valve seat assembly (4) close to the butterfly plate (3) is smaller than a stress area of one end of the valve seat assembly (4) close to the air filling cavity (15).
  9. 9. A pneumatic piston type double eccentric high performance butterfly valve according to claim 7 or 8, characterized in that a plurality of gas filling holes (151) are arranged on the valve body (1), are circumferentially distributed and are vertically communicated with the annular chute (12), each gas filling hole (151) is respectively connected with a gas filling pipeline, and a discharge valve (152) is arranged on the gas filling pipeline.
  10. 10. A pneumatic piston type double-eccentric high-performance butterfly valve according to claim 1, wherein shaft sleeves (21) sleeved at two ends of the rotating shaft (2) are arranged in the valve body (1), and are defined as a first shaft sleeve and a second shaft sleeve, the upper end of the first shaft sleeve is propped against the lower end of the self-tightening sealing filler assembly (61), and the lower end of the second shaft sleeve is propped against the bearing assembly (7).

Description

Pneumatic piston type double-eccentric high-performance butterfly valve Technical Field The invention relates to the technical field of nitrogen and oxygen production by air separation, in particular to a pneumatic piston type double-eccentric high-performance butterfly valve. Background The pressure swing adsorption air separation oxygen-making nitrogen system utilizes the selective adsorption capability of an adsorbent (such as a carbon molecular sieve or a molecular sieve) to different gas components to realize gas separation under the condition of pressure change. For example, in the nitrogen production process, air is compressed and then enters an adsorption tower, the carbon molecular sieve preferentially adsorbs oxygen, carbon dioxide and moisture to enrich nitrogen, and when the adsorbent is nearly saturated, the adsorbent is desorbed and regenerated by depressurization or vacuumizing, so that continuous nitrogen production is realized. In order to achieve periodic switching (adsorption-desorption cycle) of the adsorption column, the valve needs to be frequently operated. The pressure swing adsorption air separation oxygen production and nitrogen production system adopts a large number of double eccentric high-performance butterfly valves, the valve switching frequency is extremely high, the valve is required to be switched on and off every two minutes, the existing conventional valve can not meet the high-frequency switching requirement, the sealing ring of the valve seat is worn to leak, and the pressure swing adsorption efficiency is seriously affected. Disclosure of Invention In view of the above, the invention provides a pneumatic piston type double-eccentric high-performance butterfly valve, which aims to solve the problem that a valve seat sealing ring is easy to wear and leak under the working condition of a valve high-frequency switch in the prior art. The invention provides a pneumatic piston type double-eccentric high-performance butterfly valve, which comprises a valve body, a rotating shaft and a butterfly plate, wherein two ends of the rotating shaft penetrate through the valve body and are in rotary connection with the valve body, the butterfly plate is fixed on the rotating shaft and is positioned in the valve body, a valve seat assembly which is driven by air to move linearly along the axial direction of a medium channel of the valve body is also arranged in the valve body, one end, close to the butterfly plate, of the valve seat assembly is provided with a valve seat sealing ring which at least partially protrudes out of the valve seat assembly, at least part of the valve seat sealing ring is provided with a first inclined plane which is arranged at an angle with the axial lead of the medium channel, and the butterfly plate is provided with a second inclined plane which is consistent with the inclination direction of the first inclined plane, and a limiting structure which limits the valve seat sealing ring to move alternately in a sealing position and cancels the sealing position is arranged between the valve seat assembly and the valve body; And a packing cavity is formed between the top of the valve body and the rotating shaft, and a self-tightening sealing packing assembly which is tightly pressed by a packing gland and forms self-tightening sealing with the outer wall of the rotating shaft is arranged in the packing cavity. Preferably, the self-tightening sealing packing assembly comprises at least one group of lip-shaped sealing rings and V-shaped tensioning springs, wherein the lip-shaped sealing rings and the V-shaped tensioning springs are sleeved on the outer wall of the rotating shaft, one lip-shaped sealing ring and each V-shaped tensioning spring form a sealing unit, the V-shaped tensioning springs are arranged on the inner side wall of an opening of the lip-shaped sealing ring, and the two outer side walls of the opening of the lip-shaped sealing ring are respectively contacted with the outer wall of the rotating shaft and the side wall of the valve body. Preferably, the outer side wall of the opening of the lip seal ring is provided with a plurality of protruding parts. Preferably, in the axial direction of the rotating shaft, the packing cavity is sleeved with a plurality of sealing monomers, an intermediate annular space is formed between the lip-shaped sealing ring of one sealing monomer of two adjacent sealing monomers and the V-shaped tensioning spring of the other sealing monomer, an inner triangular annular space and an outer triangular annular space are formed between the two adjacent sealing monomers and the inner wall of the packing cavity, and the intermediate annular space, the inner triangular annular space and the outer triangular annular space of the two adjacent sealing monomers are distributed in a triangular mode. Preferably, a spring fixing groove which is profiled with the V-shaped tensioning spring is formed in the inner wall of the lip-shaped se