Two-out-of-three shutdown valve group

Abstract

The invention relates to a two-out-of-three shutdown valve group which comprises three shutdown electromagnetic valves, and each shutdown electromagnetic valve is provided with a port P, a port A, a port B and a port T; the three shutdown electromagnetic valves comprise a first shutdown electromagnetic valve, a second shutdown electromagnetic valve and a third shutdown electromagnetic valve; a P port of the first shutdown electromagnetic valve, a P port of the second shutdown electromagnetic valve and a P port of the third shutdown electromagnetic valve are all communicated with safety oil; a port T of the first shutdown electromagnetic valve, a port T of the second shutdown electromagnetic valve and a port T of the third shutdown electromagnetic valve are all communicated with the oil return port; a port A of the first shutdown electromagnetic valve is communicated with a port B of the second shutdown electromagnetic valve; a port A of the second shutdown electromagnetic valve is communicated with a port B of the third shutdown electromagnetic valve; a port A of the third shutdown electromagnetic valve is communicated with a port B of the first shutdown electromagnetic valve; error tripping can be triggered only when two or more shutdown electromagnetic valves break down, the low error tripping probability can be guaranteed, the number of the shutdown electromagnetic valves is remarkably reduced, and cost is greatly reduced.

Description

Technical Field

[0001] The invention relates to a control technology for a main steam valve of a steam turbine, and in particular to a three-out-of-two shutdown valve group. Background Art

[0002] The early steam turbine main steam valve fast closing control system used two shutdown solenoid valves with a two-out-of-one control logic. When the steam turbine was operating normally, any one or more of the shutdown solenoid valves would cause the unit to trip.

[0003] The Chinese patent with publication number CN204512043U discloses a redundant remote control shutdown control circuit for the quick closing valve of the main steam circuit of a steam turbine. This solution adopts three redundant hydraulic circuits, and only when the solenoid valves in at least two of them fail will the unit trip accidentally. This reduces the probability of the solenoid reversing valve causing the system to shut down to a certain extent, but there are problems such as numerous pipelines and complex installation, and the probability of the unit tripping accidentally is still relatively high.

[0004] The Chinese patent with publication number CN201372815Y discloses a quick-closing valve integrated electro-hydraulic actuator, which consists of four shutdown solenoid valves connected in series and then in parallel. The unit will only trip when any three solenoid valves fail or one of the two parallel oil circuits fails. This solution further reduces the probability of unit tripping, but the installation, monitoring and maintenance are difficult, and the upgrade and transformation process is cumbersome.

[0005] The Chinese patent with publication number CN111235875A discloses a four-out-of-two-speed shutdown valve group, which includes two shutdown control modules. Only when at least one of the shutdown solenoid valves in the two shutdown control modules fails will the unit trip. This solution improves and simplifies the pipeline of the shutdown speed-off valve group, thereby reducing the upgrade and transformation cost to a certain extent. However, this solution still has 4 solenoid valves and 4 cartridge valves, which is not cheap.

[0006] Based on the above problems, it is necessary to improve the existing shutdown quick-closing valve group, further simplify the structure of the shutdown quick-closing valve group and reduce costs while ensuring low false tripping. Summary of the invention

[0007] Based on the above description, the present invention provides a three-out-of-two shutdown valve group, which further reduces the cost while ensuring low false tripping. The technical solution of the present invention to solve the above technical problems is as follows: A three-out-of-two shutdown valve group, comprising three shutdown solenoid valves, each of which has a P port, an A port, a B port and a T port; The three shutdown solenoid valves include a first shutdown solenoid valve, a second shutdown solenoid valve and a third shutdown solenoid valve; the P port of the first shutdown solenoid valve, the P port of the second shutdown solenoid valve and the P port of the third shutdown solenoid valve are all connected to the safety oil; the T port of the first shutdown solenoid valve, the T port of the second shutdown solenoid valve and the T port of the third shutdown solenoid valve are all connected to the return oil port; The port A of the first shutdown solenoid valve is connected to the port B of the second shutdown solenoid valve; the port A of the second shutdown solenoid valve is connected to the port B of the third shutdown solenoid valve; the port A of the third shutdown solenoid valve is connected to the port B of the first shutdown solenoid valve.

[0008] Compared with the prior art, the technical solution of this application has the following beneficial technical effects: The three-out-of-two shutdown valve group provided in the present application will trigger a false tripping only when two or more shutdown solenoid valves fail. It realizes the three-out-of-two shutdown safety interlock function by changing the internal structure of the quick-closing valve group, which can not only ensure a low false tripping probability, but also significantly reduce the number of shutdown solenoid valves and pipeline laying, thereby greatly reducing costs.

[0009] Based on the above technical solution, the present invention can also be improved as follows.

[0010] Furthermore, the P ports of the first shutdown solenoid valve, the second shutdown solenoid valve and the third shutdown solenoid valve are all provided with pressure transmitters or flow limiters.

[0011] Furthermore, the A ports of the first shutdown solenoid valve, the second shutdown solenoid valve and the third shutdown solenoid valve are all provided with pressure switches.

[0012] Furthermore, the A ports of the first shutdown solenoid valve, the second shutdown solenoid valve and the third shutdown solenoid valve are provided with pressure transmitters or flow limiters.

[0013] Furthermore, the first shutdown solenoid valve, the second shutdown solenoid valve and the third shutdown solenoid valve have the same structure.

[0014] Furthermore, the safety oil port and the return oil port of the three-out-of-two shutdown valve group are provided with pressure gauges. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a piping principle diagram of a three-out-of-two shutdown valve group in an embodiment of the present invention; Figure 2 It is a principle diagram of the three-out-of-two shutdown valve group in the embodiment of the present invention under normal operating state; Among them, 10, the first shutdown solenoid valve; 20, the second shutdown solenoid valve; 30, the third shutdown solenoid valve. DETAILED DESCRIPTION

[0016] In order to facilitate understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. Embodiments of the present application are provided in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0017] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0018] It will be appreciated that spatial relationship terms such as "under", "beneath", "below", "under", "above", "above", etc., may be used herein to describe the relationship of an element or feature shown in the figures to other elements or features. It will be appreciated that, in addition to the orientations shown in the figures, spatial relationship terms also include different orientations of the device in use and operation. For example, if the device in the accompanying drawings is flipped, an element or feature described as "under other elements" or "under it" or "under it" will be oriented as "on" the other elements or features. Thus, the exemplary terms "under" and "under" may include both upper and lower orientations. In addition, the device may also include additional orientations (e.g., rotated 90° or other orientations), and the spatial descriptors used herein are interpreted accordingly.

[0019] It should be noted that when an element is considered to be "connected" to another element, it can be directly connected to the other element, or connected to the other element through an intermediate element. The "connection" in the following embodiments should be understood as "electrical connection", "communication connection", etc. if the connected circuits, modules, units, etc. have electrical signals or data transmission between each other.

[0020] When used herein, the singular forms "a", "an", and "said / the" may also include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include / comprise" or "have" etc. specify the presence of stated features, wholes, steps, operations, components, parts or combinations thereof, but do not exclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts or combinations thereof.

[0021] like Figure 1 and 2 As shown, the present application provides a three-out-of-two shutdown valve group, which includes three shutdown solenoid valves, each of which has a P port, an A port, a B port and a T port; The three shutdown solenoid valves include a first shutdown solenoid valve 10 , a second shutdown solenoid valve 20 and a third shutdown solenoid valve 30 .

[0022] Among them, the P port of the first shutdown solenoid valve 10, the P port of the second shutdown solenoid valve 20 and the P port of the third shutdown solenoid valve 30 are all connected to the safety oil; the T port of the first shutdown solenoid valve 10, the T port of the second shutdown solenoid valve 20 and the T port of the third shutdown solenoid valve 30 are all connected to the return oil port; Port A of the first shutdown solenoid valve 10 is connected to port B of the second shutdown solenoid valve 20 ; port A of the second shutdown solenoid valve 20 is connected to port B of the third shutdown solenoid valve 30 ; port A of the third shutdown solenoid valve 30 is connected to port B of the first shutdown solenoid valve 10 .

[0023] In the present application, the first shutdown solenoid valve 10 , the second shutdown solenoid valve 20 and the third shutdown solenoid valve 30 have the same structure.

[0024] The P ports of the first shutdown solenoid valve 10, the second shutdown solenoid valve 20 and the third shutdown solenoid valve 30 are all provided with pressure transmitters or flow limiters; the A ports of the first shutdown solenoid valve 10, the second shutdown solenoid valve 20 and the third shutdown solenoid valve 30 are all provided with pressure switches; the A ports of the first shutdown solenoid valve 10, the second shutdown solenoid valve 20 and the third shutdown solenoid valve 30 are provided with pressure transmitters or flow limiters; the safety oil port and the return oil port of the three-out-of-two shutdown valve group are provided with pressure gauges, and the safety oil port is used to connect with the main steam valve of the turbine.

[0025] In order to fully understand the three-out-of-two shutdown principle of the present application, the three-out-of-two shutdown valve group is described in three working conditions as follows: When the three shutdown solenoid valves are actuated simultaneously, the P port of the first shutdown solenoid valve 10 is connected to the A port of the first shutdown solenoid valve 10, the P port of the second shutdown solenoid valve 20 is connected to the A port of the second shutdown solenoid valve 20, the P port of the third shutdown solenoid valve 30 is connected to the A port of the third shutdown solenoid valve 30, the B port of the first shutdown solenoid valve 10 is connected to the T port of the first shutdown solenoid valve 10 to the return oil, the B port of the second shutdown solenoid valve 20 is connected to the T port of the second shutdown solenoid valve 20 to the return oil, the B port of the third shutdown solenoid valve 30 is connected to the T port of the third shutdown solenoid valve 30 to the return oil, and the unit is shut down.

[0026] When any one of the solenoid valves in the three-out-of-two shutdown valve group does not operate and the other two solenoid valves operate, taking the case where the first shutdown solenoid valve 10 does not operate and the second shutdown solenoid valve 20 and the third shutdown solenoid valve 30 operate as an example, at this time, the P port of the second shutdown solenoid valve 20 is connected to the A port of the second shutdown solenoid valve 20, the P port of the third shutdown solenoid valve 30 is connected to the A port of the third shutdown solenoid valve 30, the B port of the second shutdown solenoid valve 20 is connected to the T port of the second shutdown solenoid valve 20 to return oil, the B port of the third shutdown solenoid valve 30 is connected to the T port of the third shutdown solenoid valve 30 to return oil, the P port of the first shutdown solenoid valve 10 is not connected to the A port of the first shutdown solenoid valve 10, the B port of the first shutdown solenoid valve 10 is not connected to the T port of the first shutdown solenoid valve 10, and since the A port of the second shutdown solenoid valve 20 is connected to the B port of the third shutdown solenoid valve 30, the unit is shut down for oil unloading.

[0027] When any one of the solenoid valves in the three-out-of-two shutdown valve group is actuated and the other two solenoid valves are not actuated, for example, the first shutdown solenoid valve 10 is actuated, and the second shutdown solenoid valve 20 and the third shutdown solenoid valve 30 are not actuated, at this time, the P port of the first shutdown solenoid valve 10 is connected to the A port of the first shutdown solenoid valve 10, the B port of the first shutdown solenoid valve 10 is connected to the T port of the first shutdown solenoid valve 10 to return oil, the P port of the second shutdown solenoid valve 20 is not connected to the A port of the second shutdown solenoid valve 20, the B port of the second shutdown solenoid valve 20 is not connected to the T port of the second shutdown solenoid valve 20, the P port of the third shutdown solenoid valve 30 is not connected to the A port of the third shutdown solenoid valve 30, the B port of the third shutdown solenoid valve 30 is not connected to the T port of the third shutdown solenoid valve 30 to return oil, the safety oil cannot be depressurized, the unit does not stop, and compared with the existing quick-closing device, it can use fewer parts and effectively ensure a low false tripping probability.

[0028] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A three-out-of-two shutdown valve group, characterized in that: It includes three shutdown solenoid valves, each of which has a P port, an A port, a B port and a T port; The three shutdown solenoid valves include a first shutdown solenoid valve, a second shutdown solenoid valve and a third shutdown solenoid valve; the P port of the first shutdown solenoid valve, the P port of the second shutdown solenoid valve and the P port of the third shutdown solenoid valve are all connected to the safety oil; the T port of the first shutdown solenoid valve, the T port of the second shutdown solenoid valve and the T port of the third shutdown solenoid valve are all connected to the return oil port; The port A of the first shutdown solenoid valve is connected to the port B of the second shutdown solenoid valve; the port A of the second shutdown solenoid valve is connected to the port B of the third shutdown solenoid valve; the port A of the third shutdown solenoid valve is connected to the port B of the first shutdown solenoid valve.

2. The three-out-of-two shutdown valve group according to claim 1 is characterized in that: The P ports of the first shutdown solenoid valve, the second shutdown solenoid valve and the third shutdown solenoid valve are all provided with pressure transmitters or flow limiters.

3. The three-out-of-two shutdown valve group according to claim 1 is characterized in that: Ports A of the first shutdown solenoid valve, the second shutdown solenoid valve and the third shutdown solenoid valve are all provided with pressure switches.

4. The three-out-of-two shutdown valve group according to claim 1 is characterized in that: Ports A of the first shutdown solenoid valve, the second shutdown solenoid valve and the third shutdown solenoid valve are provided with a pressure transmitter or a flow limiter.

5. The three-out-of-two shutdown valve group according to claim 1, characterized in that: The first shutdown solenoid valve, the second shutdown solenoid valve and the third shutdown solenoid valve have the same structure.

6. The three-out-of-two shutdown valve group according to claim 1, characterized in that: The safety oil port and the return oil port of the three-out-of-two shutdown valve group are provided with pressure gauges.

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