CN112361037A - Quick-closing type air-extracting check valve - Google Patents
Quick-closing type air-extracting check valve Download PDFInfo
- Publication number
- CN112361037A CN112361037A CN202011301355.6A CN202011301355A CN112361037A CN 112361037 A CN112361037 A CN 112361037A CN 202011301355 A CN202011301355 A CN 202011301355A CN 112361037 A CN112361037 A CN 112361037A
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- CN
- China
- Prior art keywords
- valve
- valve body
- driving shaft
- air
- quick
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K15/00—Check valves
- F16K15/02—Check valves with guided rigid valve members
- F16K15/03—Check valves with guided rigid valve members with a hinged closure member or with a pivoted closure member
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K11/00—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves
- F16K11/10—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with two or more closure members not moving as a unit
- F16K11/20—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with two or more closure members not moving as a unit operated by separate actuating members
- F16K11/22—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with two or more closure members not moving as a unit operated by separate actuating members with an actuating member for each valve, e.g. interconnected to form multiple-way valves
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K31/00—Actuating devices; Operating means; Releasing devices
- F16K31/12—Actuating devices; Operating means; Releasing devices actuated by fluid
- F16K31/122—Actuating devices; Operating means; Releasing devices actuated by fluid the fluid acting on a piston
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K31/00—Actuating devices; Operating means; Releasing devices
- F16K31/44—Mechanical actuating means
- F16K31/56—Mechanical actuating means without stable intermediate position, e.g. with snap action
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K41/00—Spindle sealings
- F16K41/02—Spindle sealings with stuffing-box ; Sealing rings
Abstract
A quick-closing type air-extracting check valve comprises a valve body, wherein a valve clack is arranged inside the valve body, the side surface of the valve clack is connected with a rocker arm through a locking nut, and the upper end of the rocker arm is fixedly arranged on the outer surface of a valve rod through a shaft key; two ends of the valve rod are movably connected in the shaft holes at two ends of the valve body, one side of the valve body is fixedly provided with a pneumatic actuating mechanism through a detachable support, the pneumatic actuating mechanism comprises a driving shaft and an air cylinder, one end of the driving shaft is in transmission connection with the air cylinder, and the other end of the driving shaft is in coaxial transmission connection with one end of the valve rod; the outer surface of the driving shaft is hermetically connected with the valve body through a filler. The invention overcomes the defects of the prior art, the driving rod and the valve rod are connected through a coupling with idle stroke, the friction caused by filling is eliminated, the friction coefficient of the inner surface of the valve rod is reduced through the positioning bearing, the operating torque is small, the valve can be quickly closed within 0.5 second, a steam turbine generator unit of a thermal power station is protected, and the quick-closing valve for preventing accidents is realized.
Description
Technical Field
The invention relates to the technical field of check valves, in particular to a quick-closing type air extraction check valve.
Background
The air extraction check valve is used for non-corrosive medium pipelines such as steam and water of an air extraction system of a power plant or a thermal power plant or other systems, and is an essential key accessory of a thermal generator set in order to ensure the safe operation of a steam turbine. As a device for preventing medium from flowing backwards, the valve should be closed quickly and tightly, so as to ensure that when the water level of the feed water heater is ultrahigh, the pneumatic device part receives a liquid backflow signal and then quickly separates the steam turbine, thereby providing maximum protection for the steam turbine or an air extraction system. However, the existing air suction type check valve has large opening resistance, so that the valve cannot be closed quickly within 0.5 second, and the valve clack has low opening degree, so that the medium flow area is small, and the working efficiency of the valve is influenced.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides the quick-closing type air extraction check valve which overcomes the defects of the prior art, is reasonable in design, eliminates friction caused by filling materials by arranging the pneumatic actuator outside the valve body and connecting the driving rod and the valve rod through a coupling with an idle stroke, reduces the friction coefficient of the inner surface of the valve rod by using the positioning bearings at the two ends, has small operation torque, can quickly close the valve within 0.5 second, protects a turbo generator set of a thermal power station and prevents accidents from happening to the quick-closing valve.
In order to achieve the purpose, the invention is realized by the following technical scheme:
a quick-closing type air-extracting check valve comprises a valve body, wherein a valve clack is arranged in the valve body, the side surface of the valve clack is connected with a rocker arm into a whole through a locking nut, the upper end of the rocker arm is fixedly arranged on the outer surface of a valve rod through a shaft key, and a sealing surface of the valve clack is in sealing fit with a sealing surface of the valve body; the pneumatic actuator comprises a driving shaft and an air cylinder, one end of the driving shaft is in transmission connection with the air cylinder, and the other end of the driving shaft is in coaxial transmission connection with one end of the valve rod; the outer surface of the driving shaft is connected with the valve body in a sealing mode through a filler, and the driving shaft is limited and installed on the support through the split ring.
Preferably, equal fixed mounting has a locating bearing in the shaft hole at valve body both ends, the valve rod both ends are all installed inside locating bearing, the rocking arm upper end is through first spacing axle sleeve and the spacing axle sleeve fixed mounting of second on the valve rod surface, first spacing axle sleeve and the spacing axle sleeve of second contact with two locating bearings respectively.
Preferably, the pneumatic actuating mechanism further comprises an air source, the air outlet end of the air source is connected with the air inlet end of the pneumatic triple piece, the air outlet end of the pneumatic triple piece is connected with the air inlet end of the air cylinder through an air pipe, and the air pipe is respectively and fixedly provided with an electromagnetic valve and an exhaust valve.
Preferably, the end part of the driving shaft is connected with the end part of the valve rod through a coupling, and a free stroke clutch connection structure is adopted in the coupling.
Preferably, the valve body top is provided with the valve gap, the valve gap passes through fixing bolt fixed mounting at the valve body top, fixed mounting has the dismantlement ring on the valve gap.
Preferably, the side surface of the packing is provided with a pressing sleeve, and the pressing sleeve is fixedly installed on the side surface of the valve body through a fastening bolt.
The invention provides a quick-closing type air extraction check valve. The method has the following beneficial effects: the valve clack can be closed automatically by self weight at any position, namely the net closing moment of the valve clack at any position is more than twice of the friction moment caused by the moving part of the valve clack; the pneumatic actuator is arranged outside the valve body, and the driving rod and the valve rod are connected through a coupling with an idle stroke, so that friction caused by filling is eliminated, and the pressure loss of the valve is not influenced; through the locating bearing for both ends, reduced the coefficient of friction of valve rod internal surface to operating torque is little, can close the valve rapidly in 0.5 second, protects thermal power station turbo generator set, prevents the quick valve of closing of occurence of failure.
Drawings
In order to more clearly illustrate the present invention or the prior art solutions, the drawings that are needed in the description of the prior art will be briefly described below.
FIG. 1 is a schematic view of the present invention in a radial cross-section along a valve stem;
FIG. 2 is a schematic axial cross-sectional view of the present invention taken along the valve stem;
FIG. 3 is a schematic view of the pneumatic actuator of the present invention;
FIG. 4 is a schematic view of the construction of the rocker arm of the present invention;
FIG. 5 is a schematic view of the valve stem of the present invention;
FIG. 6 is a schematic view of the construction of the drive shaft of the present invention;
FIG. 7 is a schematic structural view of a coupling according to the present invention;
the reference numbers in the figures illustrate:
1. a valve body; 2. a valve flap; 3. locking the nut; 4. a rocker arm; 5. a valve stem; 6. a support; 7. a drive shaft; 8. a cylinder; 9. positioning the bearing; 10. a first limit shaft sleeve; 11. a second limit shaft sleeve; 12. a gas source; 13. a pneumatic triplet; 14. an electromagnetic valve; 15. an exhaust valve; 16. a coupling; 17. a valve cover; 18. disassembling the ring; 19. pressing the sleeve; 22. a filler; 23. and (4) opening the ring.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings.
In the first embodiment, as shown in fig. 1 to 7, a quick-closing type air-extraction check valve comprises a valve body 1, wherein a valve clack 2 is arranged inside the valve body 1, the side surface of the valve clack 2 is connected with a rocker arm 4 into a whole through a locking nut 3, the upper end of the rocker arm 4 is fixedly installed on the outer surface of a valve rod 5 through a shaft key, and a sealing surface of the valve clack 2 and a sealing surface of the valve body 1 form sealing fit; two ends of the valve rod 5 are movably connected in shaft holes at two ends of the valve body 1, one side of the valve body 1 is fixedly provided with a pneumatic actuating mechanism through a detachable support 6, the pneumatic actuating mechanism comprises a driving shaft 7 and an air cylinder 8, one end of the driving shaft 7 is in transmission connection with the air cylinder 8, and the other end of the driving shaft 7 is in coaxial transmission connection with one end of the valve rod 5; the outer surface of the driving shaft 7 is connected with the valve body 1 in a sealing way through a packing 22, and the driving shaft 7 is limited and installed on the bracket 6 through a double-split ring 23.
In this embodiment, the cylinder 8 includes a cylinder body, a cylinder head, a piston ring, a piston rod and a spring structure (this is the prior art and is not described again); the pneumatic actuating mechanism further comprises an air source 12, the air outlet end of the air source 12 is connected with the air inlet end of the pneumatic triple piece 13, the air outlet end of the pneumatic triple piece 13 is connected with the air inlet end of the air cylinder 8 through an air pipe, and an electromagnetic valve 14 and an exhaust valve 15 are fixedly mounted on the air pipe respectively. Under normal working conditions, the pneumatic actuating mechanism is in an air opening state, meanwhile, a spring in the cylinder compresses stored energy, when a system breaks down, an electromagnetic valve on the pneumatic device acts (loses power and closes), the cylinder exhausts quickly, meanwhile, the spring releases energy, a thrust effect is generated on the valve clack 2, and the valve clack 2 is closed quickly.
When the system normally operates, the air source 12 outputs air pressure to compress a spring in the cylinder 8, the driving shaft 7 idles to a limit position, the valve clack 2 is in a free state, and when the medium force is greater than the self gravity of the valve clack 2, the valve clack 2 is opened and enlarged along with the increase of the steam flow until the valve clack is fully opened. When the pipeline is cut off or the medium force is smaller than the gravity of the valve clack 2, the valve is automatically closed by the self gravity of the valve clack 2. When the system is in failure or in a gas loss condition, the compression spring in the cylinder 8 releases energy to drive the driving shaft 7 to rotate reversely, and then the valve rod 5 is driven to rotate, so that the valve clack 2 is assisted to be closed quickly.
In the present embodiment, the end of the drive shaft 7 and the end of the valve rod 5 are connected by a coupling 16, and a lost motion clutch connection structure is adopted in the coupling 16. Thereby when valve clack 2 closed by self gravity, rotate the connection effect at valve body 1 both ends through valve rod 5 both ends, make valve clack 2 rotate around the axle center of valve rod 5, make the sealed face of valve clack 2 and the sealed face of valve body 1 carry out sealed cooperation, and valve rod 5 is at the rotation in-process, because the valve rod 5 has idle stroke separation and reunion structure on the shaft coupling 16 with drive shaft 7 looks transmission, consequently, when valve clack 2 closed, the rotation that drives drive shaft 7 can be avoided through the shaft coupling 16 of idle stroke separation and reunion, the friction that the filler brought has then been eliminated, and can not influence the pressure loss of valve. In addition, in the embodiment, the net closing moment of the valve clack 2 at any position is more than twice of the friction moment caused by the moving part of the valve clack 2, so that the valve can be quickly closed within 0.5 second, a thermal power station steam turbine generator unit is protected, and the quick valve closing caused by accidents is prevented.
In this embodiment, the valve flap is made of a branded steel material, and the sealing surface is treated by heat resistance and hard alloy plating, and the base seal is made of a stainless steel material and has high impact resistance and corrosion resistance. And surface strengthening treatment is carried out on the sealing part, so that the valve clack can obtain enough sealing effect no matter the valve clack is opened or closed under the steam pressure of a high-low pipeline, and the sealing can reach ANSI/FCI 70-2V level.
In the second embodiment, as shown in fig. 4, as a further scheme of the first embodiment, positioning bearings 9 are fixedly installed in shaft holes at two ends of the valve body 1, two ends of the valve rod 5 are installed inside the positioning bearings 9, the upper end of the rocker arm 4 is fixedly installed on the surface of the valve rod 5 through a first limiting shaft sleeve 10 and a second limiting shaft sleeve 11, and the first limiting shaft sleeve 10 and the second limiting shaft sleeve 11 are respectively contacted with the two positioning bearings 9.
Through adopting location bearing 9 at valve body 1 both ends to reduce the coefficient of friction of valve rod 5 internal surface, and first spacing axle sleeve 10 and the spacing axle sleeve 11 of second of rocking arm 4 upper end have also realized spacing effect through two location bearing 9, so as to prevent that rocking arm 4 from taking place to move about and cause sealed face to leak.
In the third embodiment, as a further scheme of the first embodiment, a valve cover 17 is arranged on the top of the valve body 1, the valve cover 17 is fixedly installed on the top of the valve body 1 through a fixing bolt, and a disassembling ring 18 is fixedly installed on the valve cover 17. Therefore, when the valve clack 2 needs to be maintained or replaced, the fixing bolt can be directly detached, the valve cover 17 can be taken down from the top of the valve body 1 for on-site maintenance, and the valve clack 2 is replaced without detaching the whole air suction check valve from a pipeline; is convenient and quick.
In a fourth embodiment, as a further scheme of the first embodiment, a pressing sleeve 19 is arranged on the side surface of the packing 22, and the pressing sleeve 19 is fixedly installed on the side surface of the valve body 1 through a fastening bolt. The packing 22 is prevented from moving away from the original position during the rotation of the drive shaft 7 by the cooperation of the pressing sleeve 19 and the positioning bearing 9.
The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
Claims (7)
1. The utility model provides a quick-closing type air-bleed check valve which characterized in that: the valve comprises a valve body (1), wherein a valve clack (2) is arranged in the valve body (1), the side surface of the valve clack (2) is connected with a rocker arm (4) into a whole through a locking nut (3), the upper end of the rocker arm (4) is fixedly arranged on the outer surface of a valve rod (5) through a shaft key, and a sealing surface of the valve clack (2) is in sealing fit with a sealing surface of the valve body (1);
the pneumatic control valve is characterized in that two ends of the valve rod (5) are movably connected in shaft holes at two ends of the valve body (1), a pneumatic actuating mechanism is fixedly installed on one side of the valve body (1) through a detachable support (6), the pneumatic actuating mechanism comprises a driving shaft (7) and an air cylinder (8), one end of the driving shaft (7) is in transmission connection with the air cylinder (8), and the other end of the driving shaft (7) is in coaxial transmission connection with one end of the valve rod (5); the outer surface of the end part of the driving shaft (7) is hermetically connected with the valve body (1) through a packing (22), and the driving shaft (7) is limited and installed on the bracket (6) through a split ring (23).
2. The quick close bleed check valve of claim 1 wherein: equal fixed mounting has location bearing (9) in the shaft hole at valve body (1) both ends, valve rod (5) both ends are all installed inside location bearing (9), rocking arm (4) upper end is through first spacing axle sleeve (10) and spacing axle sleeve (11) fixed mounting of second at valve rod (5) surface, first spacing axle sleeve (10) and spacing axle sleeve (11) of second contact with two location bearing (9) respectively.
3. The quick close bleed check valve of claim 1 wherein: the pneumatic actuating mechanism further comprises an air source (12), the air outlet end of the air source (12) is connected with the air inlet end of the pneumatic triple piece (13), the air outlet end of the pneumatic triple piece (13) is connected with the air inlet end of the air cylinder (8) through an air pipe, and the air pipe is fixedly provided with an electromagnetic valve (14) and an exhaust valve (15) respectively.
4. The quick close bleed check valve of claim 1 wherein: the end part of the driving shaft (7) is connected with the end part of the valve rod (5) through a coupling (16), and an idle stroke clutch connection structure is adopted in the coupling (16).
5. The quick close bleed check valve of claim 1 wherein: valve body (1) top is provided with valve gap (17), valve gap (17) pass through fixing bolt fixed mounting at valve body (1) top, fixed mounting has dismantlement ring (18) on valve gap (17).
6. The quick close bleed check valve of claim 1 wherein: the side surface of the packing (22) is provided with a pressing sleeve (19), and the pressing sleeve (19) is fixedly arranged on the side surface of the valve body (1) through a fastening bolt.
7. The quick close bleed check valve of claim 1 wherein: the valve clack (2) is made of a branded steel material, and heat-resistant and hard alloy plating treatment is carried out on a sealing surface.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011301355.6A CN112361037A (en) | 2020-11-19 | 2020-11-19 | Quick-closing type air-extracting check valve |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011301355.6A CN112361037A (en) | 2020-11-19 | 2020-11-19 | Quick-closing type air-extracting check valve |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112361037A true CN112361037A (en) | 2021-02-12 |
Family
ID=74533795
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011301355.6A Pending CN112361037A (en) | 2020-11-19 | 2020-11-19 | Quick-closing type air-extracting check valve |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112361037A (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4353390A (en) * | 1979-12-06 | 1982-10-12 | Anchor/Darling Valve Company | Swing check valve with internally balanced disc |
| CN201963963U (en) * | 2010-12-13 | 2011-09-07 | 南方阀门制造有限公司 | Extraction check valve |
| CN202580156U (en) * | 2012-01-06 | 2012-12-05 | 孟国益 | Hanging gate type operation seat of extraction check valve |
| CN206904312U (en) * | 2017-06-21 | 2018-01-19 | 南通市电站阀门有限公司 | A kind of extraction check valve |
| CN109723869A (en) * | 2018-12-28 | 2019-05-07 | 江南阀门有限公司 | A kind of extraction check valve convenient for on-line maintenance |
| CN209469834U (en) * | 2018-12-28 | 2019-10-08 | 江南阀门有限公司 | A kind of extraction check valve |
-
2020
- 2020-11-19 CN CN202011301355.6A patent/CN112361037A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4353390A (en) * | 1979-12-06 | 1982-10-12 | Anchor/Darling Valve Company | Swing check valve with internally balanced disc |
| CN201963963U (en) * | 2010-12-13 | 2011-09-07 | 南方阀门制造有限公司 | Extraction check valve |
| CN202580156U (en) * | 2012-01-06 | 2012-12-05 | 孟国益 | Hanging gate type operation seat of extraction check valve |
| CN206904312U (en) * | 2017-06-21 | 2018-01-19 | 南通市电站阀门有限公司 | A kind of extraction check valve |
| CN109723869A (en) * | 2018-12-28 | 2019-05-07 | 江南阀门有限公司 | A kind of extraction check valve convenient for on-line maintenance |
| CN209469834U (en) * | 2018-12-28 | 2019-10-08 | 江南阀门有限公司 | A kind of extraction check valve |
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