CN102518823A - Valve seat sealing structure - Google Patents
Valve seat sealing structure Download PDFInfo
- Publication number
- CN102518823A CN102518823A CN2011104446592A CN201110444659A CN102518823A CN 102518823 A CN102518823 A CN 102518823A CN 2011104446592 A CN2011104446592 A CN 2011104446592A CN 201110444659 A CN201110444659 A CN 201110444659A CN 102518823 A CN102518823 A CN 102518823A
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- ring
- valve
- guard ring
- seat
- valve seat
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Abstract
The invention discloses a valve seat sealing structure with longer service life. The valve seat sealing structure comprises a valve seat ring, and a gate or a ball, wherein the valve seat ring is provided with a seal ring with a triangular section, and a guard ring made of a polytetrafluoroethylene or nylon material opposite to the surface of the gate or the ball; the compressive strength of the guard ring is higher than that of the seal ring; the guard ring is positioned on the inner side of the seal ring; and a contact surface between the guard ring and the gate or the ball is provided with a groove communicating the inside and outside of the guard ring and serving as a pressure balancing channel. A valve with the sealing structure has longer service life, and can rotate throughout the year more reliably; the operating torque of the valve is properly reduced, and the valve is convenient to open and close; and the valve can normally work under the condition that a transmission medium is dirty and disordered, the application range of the valve is widened, and the valve seat sealing structure is mainly used for flat gate valves or ball valves.
Description
Technical field
The present invention relates to a kind of plate valve or ball valve, the valve seat of especially a kind of plate valve or ball valve.
Background technique
The groundwork principle and the fixing ball valve of plate valve are similar, and the seat ring of valve valve seat receives the promotion of liquid pressure, tightly are affixed to flashboard or spheroid, and the soft sealing material that the seat ring groove on the seat ring is embedded in will contact with flashboard or spheroid, form sealing.
The ordinary flat gate valve mode that generally employing embeds at the valve seat place is O type circle fixedly, to form sealing.When valve seal, deformation takes place in valve seat O type circle under the effect of liquid pressure, fit tightly flashboard, forms sealing surface.Yet this moment, the deformation of valve seat was generally uncontrolled, and amount of deformation is mainly determined by the material mechanicalness the subject of knowledge and the object of knowledge of O type circle, from microcosmic; After the distortion; There is shear force between the notch of O type circle and seat ring groove, in the long-term process of using of valve, thereby strengthens because of variation in pressure causes the amount of deformation of O type circle; Thereby cause O type circle by seat ring notch wearing and tearing and the otch phenomenon occurs, finally cause the valve primary seal to lose efficacy.
Shearing and inordinate wear appears in the also present easily ring recess mouth place of same reason, the O type circle of ordinary ball valve, finally causes the valve primary seal to lose efficacy.
In addition, when liquid pressure was higher, the amount of deformation of O type circle increased thereupon, and the surface of contact between O type circle and flashboard or the spheroid increases, and the operation moment of torsion of valve strengthens, and was not easy to the switching manipulation of valve.
Summary of the invention
In order to overcome existing plate valve or ball seat sealing configuration short deficiency in working life, technical problem to be solved by this invention provides a kind of valve base sealing structure of longer service life.
The technical solution adopted for the present invention to solve the technical problems is: the valve base sealing structure; Comprise the valve seat seat ring, flashboard or spheroid, the valve seat seat ring is provided with seal ring corresponding to the face of flashboard or spheroid; The valve seat seat ring is corresponding to also being provided with guard ring on the face of flashboard or spheroid; The compressive strength of guard ring is higher than the compressive strength of seal ring, and guard ring is positioned at the inboard of seal ring, offers the pressure equalisation passage that is communicated with the guard ring inboard and the guard ring outside on the guard ring.
Said guard ring is the flexible rings that is installed in the guard ring groove that is provided with on the valve seat seat ring.
The material of said guard ring is teflon or nylon material.
Said guard ring is for valve seat seat ring one and protrude from valve seat seat ring and flashboard or the lip on the surface that spheroid is corresponding, and the height of lip and the deformation band of seal ring adapt.
Further be that said pressure equalisation passage is the groove that is arranged on the surface of contact of guard ring and flashboard or spheroid.
In the said structure, said seal ring is the seal ring of triangular-section, and the seat ring groove adaptive with it is dovetail groove.
The invention has the beneficial effects as follows: valve longer service life, running throughout the year more reliably; Suitably reduce the operation moment of torsion of valve, be convenient to the switching manipulation of valve; But also proper functioning under the comparatively dirty and mixed and disorderly condition of transmission medium has enlarged the Applicable scope of valve, is mainly used in plate valve or ball valve.
Description of drawings
Fig. 1 is the valve base sealing structural representation of existing plate valve.
Fig. 2 is the valve base sealing structural representation of existing ball valve.
Fig. 3 is the schematic representation of the valve base sealing structure of plate valve of the present invention.
Fig. 4 is the schematic representation of the valve base sealing structure of ball valve of the present invention.
Fig. 5 is the effect schematic representation that pressure equalisation passage is set on the guard ring.
Fig. 6 is the plan view of guard ring.
Fig. 7 is the A-A sectional view of Fig. 6.
Solid arrow is the liquid pressure direction among Fig. 1, Fig. 3, Fig. 5, and dotted arrow is depicted as seat ring groove notch place shearing force direction among Fig. 1, and the dotted line circle is depicted as the ring wear position.
Be labeled as 1-seal ring, 2-guard ring, 3-valve seat seat ring, 4-flashboard, 5-valve seat, 6-seat ring groove, 7-spheroid, 8-O type circle, 9-guard ring groove, 10-second seal ring, 20-pressure equalisation passage, 60-notch, d-distance among the figure.
Embodiment
Below in conjunction with accompanying drawing and embodiment the present invention is further specified.
As depicted in figs. 1 and 2; Existing plate valve or ball valve are when valve seal; Deformation takes place in the O type circle 8 on the valve seat 5 under the effect of liquid pressure, mainly by the material mechanicalness the subject of knowledge and the object of knowledge decision of O type circle 8, O type circle 8 fits tightly the formation sealing surface with flashboard 4 or spheroid 7 to its amount of deformation.Yet the deformation of O type circle 8 is generally uncontrolled on this moment valve seat 5, illustrated can increasing and further dwindle apart from d with pressure.From microcosmic; There is shear force between the O type circle 8 after the distortion and the notch 60 of seat ring groove 6; In the long-term process of using of valve; Strengthen because of thereby variation in pressure causes the amount of deformation of O type circle 8, thereby cause O type circle 8 by notch 60 wearing and tearing and the otch phenomenon occurs, finally cause the valve primary seal to lose efficacy.
Like Fig. 3～shown in Figure 7; Valve base sealing structure of the present invention comprises valve seat seat ring 3; Flashboard 4 or spheroid 7, valve seat seat ring 3 is provided with seal ring 1 and guard ring 2 corresponding to the face of flashboard 4 or spheroid 7, and the compressive strength of guard ring 2 is higher than the compressive strength of seal ring 1; Guard ring 2 is positioned at the inboard of seal ring 1, offers the pressure equalisation passage 20 that is communicated with the guard ring inboard and the guard ring outside on the guard ring 2.
First; Because the compressive strength of guard ring 2 is higher than the compressive strength of seal ring 1, guard ring 2 can be shared the pressure from liquid with seal ring 1, restriction valve seat seat ring 3 and flashboard 4 or spheroid 7 apart from d in the pressure surge scope that it can bear; The seal ring 1 of protection valve seat 5 is not by excess compression; And, after the pressure of seal ring 1 being shared by guard ring 2, reducing from liquid, heel and toe wear and shear action between seal ring 1 and the seat ring groove 6 are very little; Basically the seal ring 1 that can avoid causing and heel and toe wear and the shear action between the seat ring groove 6 because of seal ring 1 excess compression, thus working life of seal ring 1 greatly prolonged.Contact seal face area because of seal ring 1 and flashboard 4 or spheroid 7 diminishes simultaneously, thereby has reduced frictional force, makes that the switch of valve is lighter.
Second; Have pressure equalisation passage 20 on the guard ring 2; Make that the pressure of guard ring 2 both sides is in a basic balance, prevent that guard ring 2 from deviating under the effect of liquid pressure from the guard ring mounting groove, authorized pressure penetrates guard ring 2 and directes reach seal ring 1 position; And when pressure surge, the liquid pressure that acts on seal ring 1 there is buffer function; The sealing of valve still guarantees that with tight contact the between flashboard 4 or the spheroid 7 guard ring 2 main position-limiting actions limit the amount of deformation of seal ring 1 by seal ring 1, and this is the essential distinction of guard ring 2 and existing double layer seal ring among the present invention.
The 3rd; Guard ring 2 can will remain in the minute impurities of 7 of valve seat seat ring 3 and flashboard 4 or spheroids and wipe off when switch valve; Avoid the irregular wear of these impurity to sealing surface of seat; Therefore enlarged the Applicable scope of plate valve or ball valve, but for the comparatively dirty and mixed and disorderly environment of some transmission mediums also proper functioning.
Obviously; During design; Should make guard ring 2 protrude from valve seat seat ring 3 surface height when being in not compressed state less than seal ring 1 seal ring 1 protrude from valve seat seat ring 3 surface height but when being in limit compressive state greater than seal ring 1 seal ring 1 protrude from valve seat seat ring 3 surface height; Be that guard ring 2 protrudes from valve seat seat ring 3 surface height and will adapt the effect that guard ring 2 competence exertions are above-mentioned with the deformation band of seal ring 1.
It should be noted that; Under inevitable foozle; Because the compressive strength of guard ring 2 is greater than seal ring 1; Valve seat seat ring 3 will regulated self-position according to the shape of guard ring 2 and position rather than with the shape and the position of seal ring 1 under the liquid force in the process that flashboard 4 or spheroid 7 are drawn close; During design, should make the compensation rate of second seal ring 10 that is provided with between concentricity and the valve seat seat ring 3 and the valve seat 5 of guard ring 2, valve seat seat ring 3 and seal ring 1 be complementary, in order to avoid liquid leaks between valve seat seat ring 3 and valve seat 5.
Like Fig. 3 and shown in Figure 4, the material of guard ring 2 is preferably flexible material, and said guard ring 2 can be mounted in the flexible rings in the guard ring groove 9 that is provided with on the valve seat seat ring 3; The foozle of guard ring 2, flashboard 4 or spheroid 7 can be remedied by the distortion of guard ring 2; Thereby the processing request of flashboard 4 or spheroid 7 can reduce, and be more convenient for making, and maintenance cost is low; After losing aforementioned protective action, can only change guard ring 2 in guard ring 2 wearing and tearing to valve seat insert.
In the above scheme, recommending to select the material of said guard ring 2 is teflon or nylon, generally when the valve design working pressure is lower than 300lb, adopts teflon; Adopt nylon when being higher than 300lb, compare with the seal ring material of common employing, compressive strength is more suitable; And self lubricity is good; Moment of torsion in the time of needn't using lubricant oil to reduce valve switch, and these two kinds of materials are all highly stable, not can with common line transportation medium generation chemical reaction.
When specific (special) requirements was arranged, the material of guard ring 2 also can be selected the rigidity material, and said guard ring 2 also can be with valve seat seat ring 3 one and protrude from valve seat seat ring 3 and flashboard 4 or the lip on the surface that spheroid 7 is corresponding; The deformation band of the height of lip and seal ring 1 adapts, and at this moment, upon request Wear-resistant Treatment is carried out on surface corresponding on said lip position and flashboard 4 or the spheroid 7 usually; General compound one deck abrasion resistance alloy such as Si Taili, nickel-base alloy or the Tungsten carbites etc. selected also can be selected comparatively economic electronickelling, to improve working life; But the defective of this kind mode is that the processing request of valve seat seat ring 3, flashboard 4 or spheroid 7 is higher; Maintenance cost is higher, after guard ring 2 wearing and tearing, and must be with valve seat seat ring 3 integral replacings; Corresponding flashboard 4 or spheroid 7 also possibly need to change; And, be the rigidity friction between said lip position and flashboard 4 or the spheroid 7, with the moment of torsion that increases valve switch.
Like Fig. 5, Fig. 6 and shown in Figure 7, said pressure equalisation passage 20 is the groove on the surface of contact that is arranged on guard ring 2 and flashboard 4 or spheroid 7, and is less to the bulk strength influence of guard ring 2.
In the such scheme; Further preferred said seal ring 1 is the seal ring of triangular-section, and the seat ring groove 6 adaptive with it is dovetail groove, makes valve seat 5 stressed more even; The amount of deformation of valve seat 5 when reducing high pressure; Seal ring 1 diminishes with the contact seal face area of flashboard 4 or spheroid 7 simultaneously, thereby has reduced frictional force, makes that the switch of valve is lighter.
Embodiment one:
Like Fig. 3 and Fig. 5, Fig. 6, shown in Figure 7; Plate valve valve base sealing structure of the present invention comprises valve seat seat ring 3; Flashboard 4, valve seat seat ring 3 is provided with seal ring 1 and guard ring 2 corresponding to the face of flashboard 4, and the material of guard ring 2 is a teflon; The compressive strength of guard ring 2 is higher than the compressive strength of seal ring 1; Guard ring 2 is positioned at the inboard of seal ring 1, and the liquid pressure direction is perpendicular in the axis of guard ring 2 and the said sealing configuration, offer on the surface of contact of guard ring 2 and flashboard 4 be communicated with guard ring inboard with guard ring outside groove as pressure equalisation passage 20; Pressure equalisation passage 20 is the seal ring of triangular-section for being arranged on guard ring 2 said seal rings 1, and the seat ring groove 6 adaptive with it is dovetail groove.
Embodiment two:
Like Fig. 4 and Fig. 6, shown in Figure 7, ball seat sealing configuration of the present invention comprises valve seat seat ring 3, spheroid 7; Valve seat seat ring 3 is provided with seal ring 1 and guard ring 2 corresponding to the face of spheroid 7; The material of guard ring 2 is a teflon, and the compressive strength of guard ring 2 is higher than the compressive strength of seal ring 1, and guard ring 2 is positioned at the inboard of seal ring 1; The liquid pressure direction is perpendicular in the axis of guard ring 2 and the said sealing configuration; Offer on the surface of contact of guard ring 2 and spheroid 7 be communicated with guard ring inboard with guard ring outside groove as pressure equalisation passage 20, said seal ring 1 is the seal ring of triangular-section, the seat ring groove 6 adaptive with it is dovetail groove.
Claims (6)
1. valve base sealing structure; Comprise valve seat seat ring (3), flashboard or spheroid (4,7), valve seat seat ring (3) is provided with seal ring (1) corresponding to the face of flashboard or spheroid (4,7); It is characterized in that: also be provided with guard ring (2) on the face of valve seat seat ring (3) corresponding to flashboard or spheroid (4,7); The compressive strength of guard ring (2) is higher than the compressive strength of seal ring (1), and guard ring (2) is positioned at the inboard of seal ring (1), offers the pressure equalisation passage (20) that is communicated with the guard ring inboard and the guard ring outside on the guard ring (2).
2. valve base sealing structure as claimed in claim 1 is characterized in that: said guard ring (2) is for being installed in the flexible rings in the guard ring groove (9) that is provided with on the valve seat seat ring (3).
3. valve base sealing structure as claimed in claim 2 is characterized in that: the material of said guard ring (2) is teflon or nylon material.
4. valve base sealing structure as claimed in claim 1; It is characterized in that: said guard ring (2) is for valve seat seat ring (3) one and protrude from valve seat seat ring (3) and flashboard or the lip on the surface that spheroid (4,7) is corresponding, and the deformation band of the height of lip and seal ring (1) adapts.
5. like claim 1,2,3 or 4 described valve base sealing structures, it is characterized in that: said pressure equalisation passage (20) is the groove on the surface of contact that is arranged on guard ring (2) and flashboard or spheroid (4,7).
6. like claim 1,2,3 or 4 described valve base sealing structures, it is characterized in that: said seal ring (1) is the seal ring of triangular-section, and the seat ring groove (6) adaptive with it is dovetail groove.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110444659.2A CN102518823B (en) | 2011-12-27 | 2011-12-27 | Valve seat sealing structure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110444659.2A CN102518823B (en) | 2011-12-27 | 2011-12-27 | Valve seat sealing structure |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102518823A true CN102518823A (en) | 2012-06-27 |
| CN102518823B CN102518823B (en) | 2014-03-26 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201110444659.2A Active CN102518823B (en) | 2011-12-27 | 2011-12-27 | Valve seat sealing structure |
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| Country | Link |
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| CN (1) | CN102518823B (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102758925A (en) * | 2012-07-18 | 2012-10-31 | 嘉士凯（苏州）阀门配件有限公司 | High pressure and low pressure combination gate valve |
| CN103363141A (en) * | 2013-08-02 | 2013-10-23 | 无锡杰尔压缩机有限公司 | L-shaped sealing device of rhombic valve |
| CN104362824A (en) * | 2014-12-06 | 2015-02-18 | 南阳防爆集团股份有限公司 | Low-center high-capacity high-speed positive pressure type high-voltage three-phase asynchronous motor |
| CN105351551A (en) * | 2015-12-03 | 2016-02-24 | 兰州高压阀门有限公司 | Active sealing type valve seat |
| CN113551056A (en) * | 2019-07-10 | 2021-10-26 | 自贡自高阀门有限公司 | Horizontal shaft top-mounted pipe cleaning valve |
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| GB580988A (en) * | 1944-07-07 | 1946-09-26 | Super Oil Seals & Gaskets Ltd | Improvements relating to oil retaining and dirt excluding seals for machinery shafts and bearings |
| EP0053983A1 (en) * | 1980-12-09 | 1982-06-16 | Schlumberger Technology Corporation | Composite ball valve seal assembly |
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| CN1989363A (en) * | 2004-07-22 | 2007-06-27 | 萱场工业株式会社 | Seal construction of sliding part |
| CN201028043Y (en) * | 2007-04-08 | 2008-02-27 | 王荣贵 | Wear-resistant metal hard sealing ball valve |
| CN201057301Y (en) * | 2007-04-27 | 2008-05-07 | 费海鸿 | Angle-relaxing and three-way dual-purpose vacuum ball valve |
| CN201136549Y (en) * | 2007-10-16 | 2008-10-22 | 东风汽车有限公司 | Steering power cylinder of automobile power steering system |
| CN101725732A (en) * | 2008-10-12 | 2010-06-09 | 杨连成 | High-performance soft seal high-pressure ball valve |
| CN201547276U (en) * | 2009-09-16 | 2010-08-11 | 上海欧特莱阀门机械有限公司 | Seal ring of butterfly valve |
| CN202392142U (en) * | 2011-12-27 | 2012-08-22 | 四川精控阀门制造有限公司 | Valve seat sealing structure |
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2011
- 2011-12-27 CN CN201110444659.2A patent/CN102518823B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB580988A (en) * | 1944-07-07 | 1946-09-26 | Super Oil Seals & Gaskets Ltd | Improvements relating to oil retaining and dirt excluding seals for machinery shafts and bearings |
| EP0053983A1 (en) * | 1980-12-09 | 1982-06-16 | Schlumberger Technology Corporation | Composite ball valve seal assembly |
| CN1989363A (en) * | 2004-07-22 | 2007-06-27 | 萱场工业株式会社 | Seal construction of sliding part |
| CN2916284Y (en) * | 2006-06-16 | 2007-06-27 | 天津精通控制仪表技术有限公司 | High performance cage type control valve resistant to high temperature and low temperature |
| CN201028043Y (en) * | 2007-04-08 | 2008-02-27 | 王荣贵 | Wear-resistant metal hard sealing ball valve |
| CN201057301Y (en) * | 2007-04-27 | 2008-05-07 | 费海鸿 | Angle-relaxing and three-way dual-purpose vacuum ball valve |
| CN201136549Y (en) * | 2007-10-16 | 2008-10-22 | 东风汽车有限公司 | Steering power cylinder of automobile power steering system |
| CN101725732A (en) * | 2008-10-12 | 2010-06-09 | 杨连成 | High-performance soft seal high-pressure ball valve |
| CN201547276U (en) * | 2009-09-16 | 2010-08-11 | 上海欧特莱阀门机械有限公司 | Seal ring of butterfly valve |
| CN202392142U (en) * | 2011-12-27 | 2012-08-22 | 四川精控阀门制造有限公司 | Valve seat sealing structure |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102758925A (en) * | 2012-07-18 | 2012-10-31 | 嘉士凯（苏州）阀门配件有限公司 | High pressure and low pressure combination gate valve |
| CN103363141A (en) * | 2013-08-02 | 2013-10-23 | 无锡杰尔压缩机有限公司 | L-shaped sealing device of rhombic valve |
| CN103363141B (en) * | 2013-08-02 | 2015-11-11 | 无锡杰尔压缩机有限公司 | A kind of L shape seal arrangement of diamond valve |
| CN104362824A (en) * | 2014-12-06 | 2015-02-18 | 南阳防爆集团股份有限公司 | Low-center high-capacity high-speed positive pressure type high-voltage three-phase asynchronous motor |
| CN105351551A (en) * | 2015-12-03 | 2016-02-24 | 兰州高压阀门有限公司 | Active sealing type valve seat |
| CN113551056A (en) * | 2019-07-10 | 2021-10-26 | 自贡自高阀门有限公司 | Horizontal shaft top-mounted pipe cleaning valve |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102518823B (en) | 2014-03-26 |
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