CN111852661B - High-pressure large-flow valve assembly - Google Patents
High-pressure large-flow valve assembly Download PDFInfo
- Publication number
- CN111852661B CN111852661B CN202010441073.XA CN202010441073A CN111852661B CN 111852661 B CN111852661 B CN 111852661B CN 202010441073 A CN202010441073 A CN 202010441073A CN 111852661 B CN111852661 B CN 111852661B
- Authority
- CN
- China
- Prior art keywords
- valve
- bushing
- spring
- valve assembly
- hole
- 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.)
- Active
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02C—GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS
- F02C7/00—Features, components parts, details or accessories, not provided for in, or of interest apart form groups F02C1/00 - F02C6/00; Air intakes for jet-propulsion plants
- F02C7/22—Fuel supply systems
- F02C7/232—Fuel valves; Draining valves or systems
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Safety Valves (AREA)
Abstract
The invention provides a high-pressure large-flow valve assembly which comprises a valve and a bushing, wherein the valve is arranged in an inner hole of the bushing, the appearance of the valve is in a two-stage stepped shaft shape, the outer diameter of one end, close to a spring, of the valve is smaller than that of the other end of the valve, and the inner hole of the bushing is a two-stage stepped hole matched with the two-stage stepped shaft of the valve; the valve is provided with a blind hole extending from one end far away from the spring to the other end, the side wall of the middle part is provided with an oil through hole communicated with the blind hole, and the length of the part with smaller outer diameter of the valve is larger than that of the small hole with smaller inner diameter of the bush; in an initial state, a valve assembly oil cavity is formed between the smaller outer diameter part of the valve and the larger inner hole part of the bushing, and the side wall of the bushing is provided with a bushing oil control type hole which can be communicated with the valve assembly oil cavity. The valve assembly can effectively change the actual stress condition of the valve, thereby changing the matching design condition of the spring, facilitating the parametric design of the spring and the overall structure layout of the product, and having reliable operation, convenient structure realization and obvious effect.
Description
Technical Field
The invention relates to the technical field of fuel control systems of gas turbines, in particular to a structural design of a high-pressure large-flow valve assembly.
Background
With the higher power demand placed on gas turbines, gas turbines have evolved towards higher pressures and higher flows. The valve assembly is a fuel control mechanical structure frequently applied in a fuel control system of a gas turbine, a bushing is usually in a fixed state in the working process of the valve assembly, technical requirements such as fuel communication, flow control and the like are met through valve movement, one end of the valve is under the action of hydraulic pressure, and the other end of the valve is balanced in stress through a spring. The movement of the valve is controlled by the hydraulic pressure, and the force applied to the valve is in direct proportion to the hydraulic pressure and the force applied area of the valve. Traditional valve subassembly design is valve excircle and bush hole clearance fit, as shown in fig. 1, this structure can be better usually satisfies product function design demand, but when the valve subassembly is in high pressure and large-traffic work, in order to guarantee sufficient flow area, the valve external diameter will design a little greatly as far as possible, consequently the valve lifting surface area is great, in addition high hydraulic force acts on, the pressure that makes the valve receive in the course of the work is very big, this spring design who is used for balanced pressure for the valve other end has brought very big difficulty, need design the spring very thick sometimes, very big, sometimes even be difficult to realize, be unfavorable for product overall structure design and function realization.
Disclosure of Invention
The purpose of the invention is as follows: in order to solve the problem of difficult design of a spring for balancing the stress of the valve under the working environment with high pressure and large flow and optimize the structural design of a product, the invention provides the high-pressure large-flow valve assembly, which can effectively change the actual stress condition of the valve so as to change the matching design conditions of the spring, thereby facilitating the parametric design of the spring and the overall structural layout of the product, and the valve assembly has reliable work, convenient structural realization and obvious effect.
The technical scheme of the invention is as follows: a high-pressure large-flow valve assembly comprises a valve and a bushing, wherein the valve is arranged in an inner hole of the bushing, the valve is in a two-stage stepped shaft shape, the outer diameter of one end, close to a spring, of the valve is smaller than that of the other end of the valve, and an inner hole of the bushing is a two-stage stepped hole matched with the two-stage stepped shaft of the valve; the valve is provided with a blind hole extending from one end far away from the spring to the other end, the side wall of the middle part is provided with an oil through hole communicated with the blind hole, and the length of the part with smaller outer diameter of the valve is larger than that of the small hole with smaller inner diameter of the bush; in an initial state, a valve assembly oil cavity is formed between the smaller outer diameter part of the valve and the larger inner hole part of the bushing, and the side wall of the bushing is provided with a bushing oil control type hole which can be communicated with the valve assembly oil cavity.
Preferably, the end part of the valve close to one end of the spring is of a conical ball head structure.
Preferably, the bushing oil control hole penetrates through two opposite side walls of the bushing, and the bushing oil control hole is blocked by a part with larger outer diameter of the valve in an initial state.
Preferably, the oil passage holes extend through opposite side walls of the shutter.
Preferably, the two-stage stepped holes of the bushing are in clearance fit with the two-stage stepped shafts of the valve respectively.
Preferably, the outer circumferential surface of one end of the bushing, which is close to the spring, is provided with an annular boss.
Preferably, the inlet fuel pressure P acts on the end face of the valve, which is far away from the spring, to push the valve to move, and when the end face of the valve, which is far away from the spring, is communicated with the bushing oil control hole, the valve assembly starts to realize through flow; the end face of the valve far away from the spring is stressed to the extent that
D is the external diameter of the larger part of the external diameter of the valve, because one end of the valve, which is far away from the spring, is communicated with an oil cavity of the valve assembly through an oil through hole, the pressure of fuel oil in the oil cavity of the valve assembly is equal to the pressure P of an inlet, and the pressure of the fuel oil in the oil cavity of the valve assembly, which acts on the valve, is
d is the outer diameter of the part with smaller outer diameter of the valve, the stress direction and F Bottom end On the contrary, the valve is actually stressed as
The ratio of the actual stress of the valve to the stress of the end face of the valve far away from the spring is the square of the ratio of the outer diameter D of the smaller part of the outer diameter of the valve to the outer diameter D of the larger part of the outer diameter of the valve, namely
Preferably, an annular groove structure is arranged at the joint of the part with the larger inner diameter and the part with the smaller inner diameter of the inner hole of the bushing.
Preferably, the outer circle of the bushing is in a shape of two stepped cylinders with different diameters, each cylinder is provided with a sealing ring groove, and the sealing ring is arranged in the sealing ring groove and sealed with the shell.
The invention has the advantages that: the valve assembly can effectively reduce the actual stress of the valve in the working process, thereby optimizing the parametric design of the spring and the structural layout of the product, and meanwhile, the conical ball head design of the valve, the annular groove structure of the bushing ring and the cylindrical sealing design of the excircle size of the bushing can effectively improve the working reliability of the valve assembly and facilitate the assembly and disassembly work of the valve assembly. The large and small cylindrical structures of the valve are designed, so that the valve has the maximum displacement distance in the working process, and can play a role in limiting the valve and protecting the spring under the action of high pressure. The valve assembly structure is easy to realize, safe and reliable in work, obvious in effect under the working environment with high pressure and large flow and strong in practicability.
Drawings
Fig. 1 is a schematic structural view of a conventional shutter assembly.
Fig. 2 is a schematic structural diagram of a bushing in a high pressure high flow valve assembly according to the present invention.
Fig. 3 is a schematic structural diagram of a valve in a high pressure high flow valve assembly according to the present invention.
Fig. 4 is a schematic structural diagram of a high-pressure high-flow valve assembly according to the present invention.
Fig. 5 is a schematic view of the working state of the high-pressure high-flow valve assembly according to the present invention.
In the figure: the fuel injection valve comprises a shell 1, a lining 2, a lining 3, a valve 4, a spring seat 5, a spring 6, an end cover assembly, a lining boss, a lining inner hole annular groove b, a lining oil control hole c, a large outer circle diameter of the lining M, a small outer circle diameter of the lining M, a large cylindrical diameter of the valve D, a small cylindrical diameter of the valve D, a conical ball head structure of the valve g, an oil through hole e, an oil cavity of the valve assembly f, a maximum displacement distance of the valve L and fuel pressure of an inlet P.
Detailed Description
This section is an example of the present invention and is provided to explain and illustrate the technical solutions of the present invention.
A high-pressure large-flow valve assembly comprises a valve 3 and a bushing 2, wherein the valve 3 is arranged in an inner hole of the bushing 2, the valve 3 is in a two-stage stepped shaft shape in appearance, the outer diameter of one end, close to a spring, of the valve 3 is smaller than that of the other end of the valve 3, and the inner hole of the bushing 2 is a two-stage stepped hole in clearance fit with the two-stage stepped shaft of the valve 3; the valve 3 is provided with a blind hole extending from one end far away from the spring to the other end, the side wall of the middle part is provided with an oil through hole e communicated with the blind hole, and the oil through hole e penetrates through two opposite side walls of the valve 3. The length of the part with the smaller outer diameter of the valve 3 is larger than that of the hole with the smaller inner diameter of the bushing 2; in an initial state, a valve assembly oil cavity f is formed between the smaller outer diameter part of the valve 3 and the larger inner hole part of the bushing 2, a bushing oil control hole c capable of communicating with the valve assembly oil cavity f is formed in the side wall of the bushing 2, the bushing oil control hole c penetrates through two opposite side walls of the bushing 2, and the bushing oil control hole c in the initial state is plugged by the larger outer diameter part of the valve 3.
The end part of the valve 3 close to one end of the spring is of a conical ball head structure. The spring seat 4 and the spring 5 are used for transmitting the spring force and the valve stress, the structure has an automatic centering function, the centering of the elastic force action direction of the spring 5 and the valve can be effectively ensured, and the working reliability is improved. In the working process, the spring elasticity balances the actual stress of the valve, and the actual stress is relatively small because the stress of the valve is converted by the valve assembly, so that the parameter matching design of the spring is conveniently realized.
The outer periphery of one end of the bush 2 close to the spring is provided with an annular boss, so that the bush is convenient to disassemble.
In order to ensure that large-flow fuel can smoothly pass through the valve assembly, the outer diameter D of the larger-diameter end of the valve is designed to be large enough, the inlet fuel pressure P acts on the bottom end face of the valve 3 to push the valve to move, and when the valve moves to the bottom end face of the valve to be communicated with the bushing oil control hole c, the valve assembly starts to realize through flow. The force of the bottom end surface of the valve is
Because the bottom end of the valve (the end of the valve 3 far away from the spring) is communicated with an oil cavity f of the valve assembly through an oil through hole e, the pressure of fuel oil in the oil cavity f is equal to the pressure P at an inlet, and the pressure of the fuel oil in the oil cavity acting on the valve is
Direction of force and F Bottom end On the contrary, the valve is actually stressed as
The structural form of the valve assembly of the invention carries out the stress of the valveThe ratio of the actual stress of the valve to the stress of the bottom end surface of the valve is the square of the ratio of the diameter D of the small cylinder to the diameter D of the large cylinder, namely
For example, in order to meet the requirement of large fuel flow, the diameter of the valve flow cylinder is minimum 20mm, if the novel valve assembly structure of the invention is adopted, the diameter of the large valve cylinder is designed to be D ═ 20mm to ensure large fuel flow, and the diameter of the small valve cylinder is designed to be D ═ 10mm, under the same condition, the actual stress of the valve is only that of the traditional valve structure
The stress effect of the valve is obviously reduced. The actual valve stress is only related to the outer diameter d of the smaller diameter part of the valve, and the value of d is selected according to design requirements.
Along with the gradual increase of fuel pressure P, valve 3 atress also increases gradually and constantly compresses spring 5, and when fuel pressure P was too big, spring 5 probably is compressed and encircles, and the spring is in the state of encircling for a long time can influence spring 5 life-span. This valve subassembly structural design makes the maximum displacement distance of valve 3 be L, under the prerequisite of guaranteeing 3 opening demands of valve, through calculating the value of giving maximum displacement distance L (the value of L is less than the distance that spring 5 was compressed and enclosed) for spring 5 is spacing to valve 3 before being pressed and enclosing, can play protection spring 5's effect. Because the clearance between the valve 3 and the lining 2 is smaller, when the valve 3 moves the maximum distance, the annular groove structure b at the joint of the part with the larger inner diameter and the part with the smaller inner diameter of the inner hole of the lining can avoid the problem of valve and lining interference caused by the fact that the bottom hole of the lining is not back gouged.
The outer circle of the bushing 2 is in a stepped cylindrical shape with two sections of different diameters, a sealing ring groove is formed in each cylinder, a sealing ring is arranged in each sealing ring groove and sealed with the shell 1, and each sealing ring is only in tight contact with the shell 1 once when the valve assembly is assembled and disassembled, so that the assembly and disassembly work of products are facilitated. The bush 2 is provided with a boss structure a, so that the valve assembly can be conveniently taken out of the shell 1 by matching with a tool. The end cover assembly 6 fixes the bushing 2, ensures the function of the valve assembly and realizes sealing with the shell 1.
The present invention is not limited to the above embodiments, and any structural changes made under the teaching of the present invention shall fall within the protection scope of the present invention, which is similar or similar to the technical solutions of the present invention. The techniques, shapes, and configurations not described in detail in the present invention are all known techniques.
Claims (9)
1. A high-pressure large-flow valve assembly is characterized by comprising a valve (3) and a bushing (2), wherein the valve (3) is arranged in an inner hole of the bushing (2), the valve (3) is in a two-stage stepped shaft shape, the outer diameter of one end, close to a spring, of the valve (3) is smaller than that of the other end of the valve, and the inner hole of the bushing (2) is a two-stage stepped hole matched with the two-stage stepped shaft of the valve (3); the valve (3) is provided with a blind hole extending from one end far away from the spring to the other end, the side wall of the middle part is provided with an oil through hole e communicated with the blind hole, and the length of the part with smaller outer diameter of the valve (3) is larger than that of the hole with smaller inner diameter of the bushing (2); in an initial state, a valve assembly oil cavity f is formed between the part with the smaller outer diameter of the valve (3) and the part with the larger inner hole of the bushing (2), and a bushing oil control hole c capable of being communicated with the valve assembly oil cavity f is formed in the side wall of the bushing (2).
2. A high pressure high flow valve assembly according to claim 1 characterised in that the valve (3) is of conical bulb design at the end adjacent the spring.
3. A high pressure high flow valve assembly according to claim 1, characterised in that the bushing oil control holes c extend through opposite side walls of the bushing (2), the bushing oil control holes c being initially blocked by a larger outer diameter portion of the valve (3).
4. A high pressure high flow valve assembly according to claim 1, characterised in that the oil passage e extends through opposite side walls of the valve (3).
5. A high pressure high flow valve assembly according to claim 1, characterized in that the two step holes of the bushing (2) are clearance fitted with the two step shafts of the valve (3), respectively.
6. A high pressure high flow valve assembly according to claim 1, characterised in that the bush (2) has an annular projection on its outer circumference adjacent to the end of the spring.
7. A high-pressure high-flow valve assembly according to claim 1, characterized in that the inlet fuel pressure P acts on the end face of the valve (3) far away from the spring to push the valve (3) to move, and when the end face of the valve (3) far away from the spring is communicated with the bushing oil control hole c, the valve assembly starts to realize through-flow; the end face of the valve (3) far away from the end face of the spring is stressed by the force
D is the diameter of the larger part of the outer diameter of the valve, one end of the valve, which is far away from the spring, is communicated with an oil cavity f of the valve assembly through an oil through hole e, the pressure of fuel oil in the oil cavity f of the valve assembly is equal to the pressure P at an inlet, and the pressure of the fuel oil in the oil cavity f of the valve assembly acting on the valve (3) is
d is the diameter of the smaller outer diameter part of the valve, the stress direction is equal to F Bottom end On the contrary, the valve is actually stressed as
The ratio of the actual stress of the valve (3) to the stress of the end face of the valve far away from the spring is the square of the ratio of the diameter D of the small cylinder to the diameter D of the large cylinder, namely
8. A high pressure high flow valve assembly according to claim 1 wherein the bushing bore is provided with an annular groove formation at the junction of the larger and smaller inner diameter portions.
9. A high pressure high flow valve assembly according to claim 1 characterised in that the external circumference of the bush (2) is of stepped cylindrical shape, each cylinder being sealed to the housing (1) by a sealing ring.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010441073.XA CN111852661B (en) | 2020-05-22 | 2020-05-22 | High-pressure large-flow valve assembly |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010441073.XA CN111852661B (en) | 2020-05-22 | 2020-05-22 | High-pressure large-flow valve assembly |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111852661A CN111852661A (en) | 2020-10-30 |
| CN111852661B true CN111852661B (en) | 2022-08-05 |
Family
ID=72985140
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010441073.XA Active CN111852661B (en) | 2020-05-22 | 2020-05-22 | High-pressure large-flow valve assembly |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111852661B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112392605B (en) * | 2020-10-30 | 2023-10-20 | 中国航发西安动力控制科技有限公司 | Differential pressure mechanism |
| CN114109611B (en) * | 2021-11-05 | 2023-05-23 | 中国航发西安动力控制科技有限公司 | Piston type oil distributing valve assembly with double-spring structure |
Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB806207A (en) * | 1954-12-22 | 1958-12-23 | Bendix Aviat Corp | Improvements in or relating to governors, more particularly for gas turbine engines |
| US5797418A (en) * | 1995-01-11 | 1998-08-25 | Societe Nationale D'etude Et De Construction De Moteurs D'aviation "Snecma" | Differential pressure detector with reduced reaction forces |
| JPH10331998A (en) * | 1997-06-02 | 1998-12-15 | Unisia Jecs Corp | Flow control device |
| US6446613B1 (en) * | 2001-12-20 | 2002-09-10 | Stanadyne Corporation | Two-stage pressure limiting valve |
| JP2005016585A (en) * | 2003-06-24 | 2005-01-20 | Nachi Fujikoshi Corp | Automatic speed change selector valve for two-speed hydraulic motor |
| CN1661269A (en) * | 2004-02-25 | 2005-08-31 | 沃尔沃建造设备控股（瑞典）有限公司 | Pilot operated relief valve |
| CN101684751A (en) * | 2008-09-22 | 2010-03-31 | 贵州红林机械有限公司 | Fuel cut-off valve of reheat fuel control unit of turbofan engine |
| CN102575782A (en) * | 2009-08-17 | 2012-07-11 | 盾安美斯泰克股份有限公司 | Micromachined device and control method |
| CN106762156A (en) * | 2016-12-21 | 2017-05-31 | 长春航空液压控制有限公司 | Engine fuel turns off valve assembly |
| CN107013339A (en) * | 2017-05-28 | 2017-08-04 | 西安成立航空制造有限公司 | A kind of aero-engine fuel nozzle main combustion stage working connection valve and its application method |
| CN109196280A (en) * | 2016-05-31 | 2019-01-11 | 赛峰飞机发动机公司 | The holding part of washer for turbomachine injector |
| CN109522638A (en) * | 2018-12-14 | 2019-03-26 | 中国航发贵州红林航空动力控制科技有限公司 | One kind point circle partial pressure type metering valve bushing-type pore structure and design method |
| EP3643951A1 (en) * | 2018-10-25 | 2020-04-29 | Hamilton Sundstrand Corporation | Method for modifying valve assembly |
-
2020
- 2020-05-22 CN CN202010441073.XA patent/CN111852661B/en active Active
Patent Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB806207A (en) * | 1954-12-22 | 1958-12-23 | Bendix Aviat Corp | Improvements in or relating to governors, more particularly for gas turbine engines |
| US5797418A (en) * | 1995-01-11 | 1998-08-25 | Societe Nationale D'etude Et De Construction De Moteurs D'aviation "Snecma" | Differential pressure detector with reduced reaction forces |
| JPH10331998A (en) * | 1997-06-02 | 1998-12-15 | Unisia Jecs Corp | Flow control device |
| US6446613B1 (en) * | 2001-12-20 | 2002-09-10 | Stanadyne Corporation | Two-stage pressure limiting valve |
| JP2005016585A (en) * | 2003-06-24 | 2005-01-20 | Nachi Fujikoshi Corp | Automatic speed change selector valve for two-speed hydraulic motor |
| CN1661269A (en) * | 2004-02-25 | 2005-08-31 | 沃尔沃建造设备控股（瑞典）有限公司 | Pilot operated relief valve |
| CN101684751A (en) * | 2008-09-22 | 2010-03-31 | 贵州红林机械有限公司 | Fuel cut-off valve of reheat fuel control unit of turbofan engine |
| CN102575782A (en) * | 2009-08-17 | 2012-07-11 | 盾安美斯泰克股份有限公司 | Micromachined device and control method |
| CN109196280A (en) * | 2016-05-31 | 2019-01-11 | 赛峰飞机发动机公司 | The holding part of washer for turbomachine injector |
| CN106762156A (en) * | 2016-12-21 | 2017-05-31 | 长春航空液压控制有限公司 | Engine fuel turns off valve assembly |
| CN107013339A (en) * | 2017-05-28 | 2017-08-04 | 西安成立航空制造有限公司 | A kind of aero-engine fuel nozzle main combustion stage working connection valve and its application method |
| EP3643951A1 (en) * | 2018-10-25 | 2020-04-29 | Hamilton Sundstrand Corporation | Method for modifying valve assembly |
| CN109522638A (en) * | 2018-12-14 | 2019-03-26 | 中国航发贵州红林航空动力控制科技有限公司 | One kind point circle partial pressure type metering valve bushing-type pore structure and design method |
Non-Patent Citations (2)
| Title |
|---|
| 可变几何通道控制执行装置动态特性研究;张伟等;《燃气涡轮试验与研究》;20161215(第06期);全文 * |
| 燃油调节器起动供油特性研究;罗畅敏等;《燃气涡轮试验与研究》;20160815(第04期);全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111852661A (en) | 2020-10-30 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111852661B (en) | High-pressure large-flow valve assembly | |
| EP2163767B1 (en) | Multiple-stage centrifugal pump including a controlled leakage hydraulic balancing drum | |
| CN107061834B (en) | Built-in driving axial-flow type regulating valve | |
| CN110131477B (en) | Multistage throttle labyrinth relief pressure valve | |
| CN103527787B (en) | A kind of control valve for power station adopting the metal sealing coil structures of convenient disassembly | |
| CN106439330B (en) | A kind of end is equipped with the hard tube connector of bulge loop | |
| CN219954238U (en) | Electronic expansion valve | |
| CN210461828U (en) | Flow differential pressure setting valve | |
| CN204420230U (en) | A kind of high-pressure solenoid valve of docking with pressure reducing regulator | |
| CN202719182U (en) | Five-piece-type forged steel ball valve | |
| CN210153242U (en) | Regulating valve with pressure reducing and noise reducing functions | |
| CN210830637U (en) | Safety valve structure for piston type pressure reducer | |
| CN104653809A (en) | Pressure balanced metal valve seat sealing structure of high pressure adjusting ball valve | |
| CN112797221A (en) | Pilot axial flow type safety valve | |
| CN204664465U (en) | High-pressure regulation ball valve pressure balance type metal seat valve sealing configuration | |
| CN202812559U (en) | High-pressure knuckle joint | |
| CN201100502Y (en) | Spherical pipeline compensator | |
| CN205207705U (en) | Disk seat of eccentric butterfly valve | |
| CN214036952U (en) | Fireproof plug valve with lining | |
| CN213743420U (en) | Piston overshoot prevention structure for pressure-adjustable disc cutter | |
| CN219655313U (en) | Top-mounted ball valve | |
| CN220769832U (en) | Direct-acting low-pressure overflow valve | |
| CN109027352B (en) | Pressure operated valve | |
| CN220749042U (en) | Leak-proof corrugated pipe mechanical sealing structure | |
| CN210069001U (en) | Vortex-resistant anti-rotation large-caliber sleeve valve |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |