Steam turbine emergency trip test device and emergency trip test method

Abstract

The present application discloses a steam turbine emergency shutoff test device and an emergency shutoff test method, the device comprising a diaphragm valve connected to the oil outlet of the main oil pump of the steam turbine, an emergency shutoff pipeline and two oil injection branches; the emergency shutoff pipeline comprises a reset solenoid valve, two emergency shutoff branches corresponding to the two oil injection branches respectively, and an oil filling pipeline; the oil filling pipeline is connected between the two emergency shutoff branches; an oil filling valve is arranged in the oil filling pipeline, and an oil pressure monitoring device is arranged in each of the two emergency shutoff branches. The present application connects the oil filling pipeline between the two emergency shutoff branches, and after the oil injection test of one of the emergency shutoff branches is completed, the oil filling valve is first opened to allow the oil of the other emergency shutoff branch to be filled with oil, and then the emergency shutoff branch is connected to prevent the unit from tripping due to an instantaneous drop in oil pressure at the moment of connection.

Description

Technical Field

[0001] The present application relates to the technical field of steam turbines, and in particular to a steam turbine emergency shutdown test device and an emergency shutdown test method. Background Art

[0002] Steam turbine generator sets are generally equipped with emergency shut-off devices, and oil injection tests are required after the unit has been in continuous operation for 2000 hours or has been shut down for a long time and has undergone corresponding maintenance. In particular, when the oil injection test is carried out during the operation of the unit, due to a group of impactors being cut off, the impactors will operate during the oil injection test, causing the emergency shut-off valve to operate, and the oil stored in the pipeline between the cut-off solenoid valve and its corresponding emergency shut-off valve will be completely drained. Therefore, when the emergency shut-off valve is reset after the oil injection test, the pipeline between the emergency shut-off valve and its cut-off valve is in an empty state without medium. At this time, restoring the cut-off solenoid valve will cause the safety oil pressure to drop rapidly and instantly, resulting in the accident of the unit tripping. Summary of the invention

[0003] The purpose of the present application is to overcome the deficiency in the prior art that the unit is easily tripped after the oil injection test, and to provide a steam turbine emergency shutdown test device and an emergency shutdown test method.

[0004] The technical solution of the present application provides a steam turbine emergency trip test device, comprising a diaphragm valve connected to the oil outlet of the main oil pump of the steam turbine, an emergency trip pipeline and two oil injection branches;

[0005] The emergency shutoff pipeline includes a reset solenoid valve, two emergency shutoff branches corresponding to the two fuel injection branches, and an oil filling pipeline;

[0006] One end of the reset solenoid valve is connected to the oil outlet of the main oil pump, and the other end is connected to the two emergency shutoff branches, the two emergency shutoff branches are connected in parallel between the reset solenoid valve and the diaphragm valve, and the oil filling pipeline is connected between the two emergency shutoff branches;

[0007] An oil filling valve is arranged in the oil filling pipeline, and an oil pressure monitoring device is arranged in each of the two emergency shut-off branches.

[0008] Furthermore, at least one first throttling orifice plate is provided in the oil filling pipeline, the aperture of the first throttling orifice plate is less than or equal to 2 mm, and the diameter of the oil filling pipeline is 8 to 10 mm.

[0009] Furthermore, the oil pressure monitoring device is an oil pressure switch.

[0010] Furthermore, the oil filling valve is a manual valve.

[0011] Furthermore, the emergency tripping branch includes an emergency tripping device and a cut-off solenoid valve;

[0012] The emergency circuit breaker is connected to the reset electromagnetic valve, and the cutoff electromagnetic valve is connected between the diaphragm valve and the emergency circuit breaker.

[0013] Furthermore, two ends of the oil filling pipeline are respectively connected between the cut-off solenoid valve and the emergency trip device in the two emergency trip branches.

[0014] Furthermore, a second throttling orifice plate is connected between the oil outlet of the main oil pump and the diaphragm valve, and the aperture of the second throttling orifice plate is 6 mm.

[0015] Furthermore, an injection solenoid valve is provided in the injection branch, and the injection solenoid valve is connected to the oil outlet of the main oil pump and one of the impact sub-oil tanks of the injection device.

[0016] The technical solution of the present application also provides a critical trip test method for the steam turbine critical trip test device as described above, when the steam turbine is running, the two oil injection branches are closed, the main oil pump supplies oil to the diaphragm valve and the critical trip pipeline, and the oil filling valve of the oil filling pipeline is closed, and the method includes controlling one of the critical trip branches to be closed;

[0017] Controlling the fuel injection branch corresponding to the emergency cutoff branch to be turned on, triggering the fuel injection branch to inject fuel;

[0018] After the injection is completed, the oil filling valve is gradually opened after the reset solenoid valve is operated until the oil pressure in the emergency trip branch reaches the preset oil pressure value, and then the oil filling valve is closed;

[0019] Controlling the emergency tripping branch to be turned on;

[0020] Repeat all the above steps to control another critical trip branch for testing.

[0021] Further, the emergency shutoff branch includes an emergency shutoff device and a cut-off solenoid valve; the emergency shutoff device is connected to the reset solenoid valve, and the cut-off solenoid valve is connected between the diaphragm valve and the emergency shutoff device;

[0022] When the cut-off solenoid valve is controlled to be closed, the emergency tripping branch is closed;

[0023] When the cut-off solenoid valve is controlled to open, the emergency shut-off branch is connected.

[0024] After adopting the above technical solution, the following beneficial effects are achieved:

[0025] The present application connects an oil filling pipeline between two emergency shut-off branches. After the oil injection test is completed on one of the emergency shut-off branches, the oil filling valve is first opened to allow the oil from the other emergency shut-off branch to be filled, and then the emergency shut-off branch is turned on to prevent the unit from tripping due to an instantaneous drop in oil pressure at the moment of turn-on. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The disclosure of the present application will become easier to understand with reference to the accompanying drawings. It should be understood that these drawings are only for illustrative purposes and are not intended to limit the scope of protection of the present application. In the drawings:

[0027] Figure 1 It is a structural schematic diagram of a steam turbine emergency trip test device in one embodiment of the present application;

[0028] Figure 2 It is a flow chart of a steam turbine emergency shutdown test method in one embodiment of the present application.

[0029] Reference table of reference numerals:

[0030] Diaphragm valve 01;

[0031] Fuel injection branch 02: fuel injection solenoid valve 21, fuel injection device 22;

[0032] Reset solenoid valve 03;

[0033] Emergency trip branch 04: oil pressure monitoring device 41, emergency trip device 42, cut-off solenoid valve 43;

[0034] Oil filling pipeline 05: oil filling valve 51, first throttle orifice plate 52;

[0035] The second throttle orifice plate 06. DETAILED DESCRIPTION

[0036] The specific implementation of the present application is further described below with reference to the accompanying drawings.

[0037] It is easy to understand that according to the technical solution of the present application, without changing the essential spirit of the present application, a variety of structural modes and implementation modes that can be replaced by those skilled in the art can be replaced with each other. Therefore, the following specific implementation modes and drawings are only exemplary descriptions of the technical solution of the present application, and should not be regarded as the entirety of the present application or as a limitation or restriction on the technical solution of the application.

[0038] The directional terms such as up, down, left, right, front, back, front, back, top, bottom, etc. mentioned or may be mentioned in this specification are defined relative to the structures shown in the drawings. They are relative concepts and may change accordingly according to their different positions and different usage conditions. Therefore, these or other directional terms should not be interpreted as restrictive terms. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0039] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above-mentioned in this application can be understood according to the specific circumstances.

[0040] Steam turbine emergency trip test device:

[0041] The steam turbine emergency shutdown test device in the embodiment of the present application is as follows: Figure 1 As shown, it includes a diaphragm valve 01 connected to the oil outlet of the main oil pump of the steam turbine, an emergency shutoff pipeline and two oil injection branches 02;

[0042] The emergency shutoff pipeline includes a reset solenoid valve 03, two emergency shutoff branches 04 corresponding to the two fuel injection branches 02, and an oil filling pipeline 05;

[0043] One end of the reset solenoid valve 03 is connected to the oil outlet of the main oil pump, and the other end is connected to two emergency shutoff branches 04. The two emergency shutoff branches 04 are connected in parallel between the reset solenoid valve 03 and the diaphragm valve 01. The oil filling pipeline 05 is connected between the two emergency shutoff branches 04.

[0044] An oil filling valve 51 is provided in the oil filling pipeline 05 , and an oil pressure monitoring device 41 is provided in each of the two emergency shut-off branches 04 .

[0045] Specifically, each emergency tripping branch 04 includes an emergency tripping device 42 and a cut-off solenoid valve 43;

[0046] The emergency circuit breaker 42 is connected to the reset electromagnetic valve 03 , and the cutoff electromagnetic valve 43 is connected between the diaphragm valve 01 and the emergency circuit breaker 42 .

[0047] One end of the oil filling pipeline 05 is connected between the cut-off solenoid valve 43 and the emergency circuit breaker 42 in one of the emergency circuit breaker branches 04, and the other end is connected between the cut-off solenoid valve 43 and the emergency circuit breaker 42 in the other emergency circuit breaker branch 04, so that the pipelines between the cut-off solenoid valve 43 and the emergency circuit breaker 42 in the two emergency circuit breaker branches 04 can be filled with oil.

[0048] The main oil pump of the steam turbine supplies oil to the emergency trip test device. The main oil pump is connected to the injection branch 02, the emergency trip pipeline and the diaphragm valve 01. One end of the emergency trip pipeline is connected to the oil outlet of the main oil pump, and the other end is connected to the upper chamber of the diaphragm valve 01.

[0049] When the steam turbine is operating normally, the two oil injection branches 02 are closed, the two emergency shut-off branches 04 are connected, and the two emergency shut-off branches 04 are subjected to oil injection tests one after another. When conducting the oil injection test, first control the cut-off solenoid valve 43 in the tested emergency shut-off branch 04 to close, cut off the pipeline between the emergency shut-off branch 04 and the diaphragm valve 01, and prevent the oil injection test from affecting the normal operation of the steam turbine; then control the oil injection branch 02 corresponding to the tested emergency shut-off branch 04 to be connected, and the main oil pump supplies oil to the oil injection branch 02 to trigger the oil injection device to spray oil, knock out the impactor in the oil injection device, trigger the emergency shut-off device 42 in the tested emergency shut-off branch 04 to operate and open the oil circuit, and release the oil pressure between the emergency shut-off device 42 and the diaphragm valve 01. The cut-off solenoid valve 43 in the cut-off branch 04 is in the closed state, and at this time, the emergency cut-off device 42 only releases the oil pressure between the emergency cut-off device 42 and the cut-off solenoid valve 43; after the oil injection is completed, the reset solenoid valve 03 is operated to reset the emergency cut-off device 42, and then the oil filling valve 51 is opened to fill the oil circuit that releases the oil pressure in the tested emergency cut-off branch 04, and the oil pressure monitoring device is used to determine whether the oil pressure reaches the preset value, and finally the cut-off solenoid valve 43 in the tested emergency cut-off branch 04 is opened, and the pipeline between the emergency cut-off branch 04 and the diaphragm valve 01 is connected, and the test of the emergency cut-off branch 04 is completed. Then, another emergency cut-off branch 04 is tested in the same way.

[0050] Among them, the oil pressure monitoring device 41 in the emergency shut-off branch 04 can adopt an oil pressure gauge or other equipment with an oil pressure indication function, so that the staff can understand the oil filling condition of the emergency shut-off branch 04.

[0051] In the embodiment of the present application, after the oil injection, when the oil pressure between the tested emergency shut-off device 42 and the diaphragm valve 01 is released, the emergency shut-off device 42 is reset, and then the oil filling pipeline 05 is opened to fill the oil between the tested emergency shut-off device 42 and the diaphragm valve 01, and then the cut-off solenoid valve 43 is opened. This can avoid the problem in the prior art that the oil pressure between the emergency shut-off device 42 and the diaphragm valve 01 is released, directly opening the cut-off solenoid valve 43, causing the oil pressure in the upper chamber of the diaphragm valve 01 to release and causing the unit to shut down, thereby ensuring that the oil injection test has no impact on the normal operation of the unit.

[0052] In one of the embodiments, at least one first throttling orifice plate 52 is further provided in the oil filling pipeline 05, the aperture of the first throttling orifice plate 52 is less than or equal to 2 mm, and the diameter of the oil filling pipeline is 8-10 mm.

[0053] by Figure 1 Taking the steam turbine emergency shutdown test device shown as an example, two first throttling orifice plates 52 are provided in the oil filling pipeline 05, respectively provided at the two ends of the oil filling pipeline 05. The provision of the two throttling orifice plates 52 ensures the balance of the oil amount in the oil filling pipeline 05.

[0054] The aperture of the two first throttling orifice plates 52 is less than or equal to 2 mm, and the diameter of the oil filling pipeline is set to 8-10 mm, so as to limit the oil volume in the oil filling pipeline 05 and avoid the oil pressure of the main oil circuit being too low due to the addition of the filling pipeline 05, so as to ensure the normal operation of the turbine.

[0055] In one of the embodiments, the oil pressure monitoring device 41 is configured as an oil pressure switch. When it is detected that the oil pressure in the emergency trip branch 04 reaches a set value, an indicator light is turned on to indicate that the emergency trip branch 04 is completely filled with oil.

[0056] In one embodiment, the oil filling valve 51 is configured as a manual valve. Since the oil flow rate of the oil filling pipeline 05 is relatively low and the required oil filling amount is not large, the staff manually opens the oil filling valve 51, which enables faster and more accurate oil filling.

[0057] In one embodiment, if Figure 1 As shown, a second throttling orifice 06 is also connected between the oil outlet of the main oil pump and the diaphragm valve 01. The aperture of the second throttling orifice 06 is 6 mm, which is larger than the aperture of the first throttling orifice 52, ensuring that there is a stable and sufficient amount of oil in the pipeline between the oil outlet of the main oil pump and the diaphragm valve 01.

[0058] In one embodiment, if Figure 1As shown, an injection solenoid valve 21 is provided in the injection branch 02. The injection solenoid valve 21 is connected to the oil outlet of the main oil pump and one of the impact sub-oil tanks of the injection device 22. When the injection test is performed, the injection solenoid valve 21 is opened to trigger the corresponding impact sub-oil tank to fly out and trigger the corresponding emergency shut-off device 42 to operate.

[0059] As needed, the above technical solutions can be combined to achieve the best technical effect.

[0060] Emergency trip test method of steam turbine emergency trip test device:

[0061] The technical solution of the present application also provides a critical trip test method for the steam turbine critical trip test device as described above, when the steam turbine is running, the two oil injection branches are closed, the main oil pump supplies oil to the diaphragm valve and the critical trip pipeline, and the oil filling valve of the oil filling pipeline is closed, and the method includes controlling one of the critical trip branches to be closed;

[0062] Controlling the fuel injection branch corresponding to the emergency cutoff branch to be turned on, triggering the fuel injection branch to inject fuel;

[0063] After the injection is completed, the oil filling valve is gradually opened after the reset solenoid valve is operated until the oil pressure in the emergency trip branch reaches the preset oil pressure value, and then the oil filling valve is closed;

[0064] Controlling the emergency tripping branch to be turned on;

[0065] Repeat all the above steps to control another critical trip branch for testing.

[0066] The embodiment of the present application, after the oil injection, when the oil pressure in the tested emergency shut-off branch is leaked, operates the reset solenoid valve and then operates the oil filling valve to gradually open, connects the oil filling pipeline to fill the tested emergency shut-off branch with oil, and then controls the test emergency shut-off branch to be connected. This can avoid the problem in the prior art of directly connecting the emergency shut-off branch when the oil pressure in the emergency shut-off branch is leaked, resulting in the oil pressure in the upper chamber of the diaphragm valve 01 leaking and causing the unit to shut down, thereby ensuring that the oil injection test has no impact on the normal operation of the unit.

[0067] In a specific embodiment, the emergency tripping branch includes an emergency tripping device and a cut-off solenoid valve; the emergency tripping device is connected to the reset solenoid valve, and the cut-off solenoid valve is connected between the diaphragm valve and the emergency tripping device;

[0068] When the cut-off solenoid valve is controlled to be closed, the emergency tripping branch is closed;

[0069] When the cut-off solenoid valve is controlled to open, the emergency shut-off branch is connected.

[0070] Figure 2A flowchart showing an emergency trip test method of a steam turbine emergency trip test device in a specific embodiment is shown, including

[0071] Step S201: Control the cut-off solenoid valve in one of the emergency tripping branches to close;

[0072] Step S202: controlling the fuel injection solenoid valve in the fuel injection branch corresponding to the emergency shutoff branch to open, triggering the fuel injection branch to inject fuel;

[0073] Step S203: after the injection is completed, the reset solenoid valve is operated to close the emergency trip device in the emergency trip branch;

[0074] Step S204: operating the oil filling valve to gradually open until the oil pressure in the emergency trip branch reaches a preset oil pressure value, and then closing the oil filling valve;

[0075] Step S205: Control the cut-off solenoid valve in the emergency tripping branch to open.

[0076] Repeat the above steps S201 to S205 to test another critical tripping branch.

[0077] The above description is only the principle and preferred embodiment of the present application. It should be pointed out that for ordinary technicians in this field, the implementation methods obtained by appropriately combining the technical solutions disclosed in different embodiments are also included in the technical scope of the present invention. On the basis of the principle of the present application, several other variations can be made, which should also be regarded as the protection scope of the present application.

Claims

1. A steam turbine emergency shutdown test device, characterized in that: It includes a diaphragm valve connected to the oil outlet of the main oil pump of the steam turbine, an emergency shut-off pipeline and two oil injection branches; The emergency shutoff pipeline includes a reset solenoid valve, two emergency shutoff branches corresponding to the two fuel injection branches, and an oil filling pipeline; One end of the reset solenoid valve is connected to the oil outlet of the main oil pump, and the other end is connected to the two emergency shutoff branches, the two emergency shutoff branches are connected in parallel between the reset solenoid valve and the diaphragm valve, and the oil filling pipeline is connected between the two emergency shutoff branches; An oil filling valve is provided in the oil filling pipeline, and an oil pressure monitoring device is provided in each of the two emergency tripping branches; The emergency tripping branch includes an emergency tripping device and a cut-off solenoid valve; The emergency breaker is connected to the reset solenoid valve, and the cut-off solenoid valve is connected between the diaphragm valve and the emergency breaker; After the oil injection is completed, the reset solenoid valve is operated to reset the emergency trip device, and then the oil filling valve is opened to fill the oil circuit in the emergency trip branch circuit under test with oil pressure released.

2. The steam turbine emergency shutdown test device according to claim 1, characterized in that: At least one first throttling orifice plate is also provided in the oil filling pipeline, the aperture of the first throttling orifice plate is less than or equal to 2 mm, and the diameter of the oil filling pipeline is 8-10 mm.

3. The steam turbine emergency shutdown test device according to claim 1, characterized in that: The oil pressure monitoring device is an oil pressure switch.

4. The steam turbine emergency shutdown test device according to claim 1, characterized in that: The oil filling valve is a manual valve.

5. The steam turbine emergency shutdown test device according to claim 4, characterized in that: The two ends of the oil filling pipeline are respectively connected between the cut-off solenoid valve and the emergency trip device in the two emergency trip branches.

6. The steam turbine emergency shutdown test device according to any one of claims 1 to 4, characterized in that: A second throttling orifice plate is also connected between the oil outlet of the main oil pump and the diaphragm valve, and the aperture of the second throttling orifice plate is 6 mm.

7. The steam turbine emergency shutdown test device according to any one of claims 1 to 4, characterized in that: An injection solenoid valve is provided in the injection branch, and the injection solenoid valve is connected to the oil outlet of the main oil pump and one of the impact sub-oil tanks of the injection device.

8. An emergency trip test method for a steam turbine emergency trip test device according to any one of claims 1 to 7, characterized in that: When the steam turbine is running, the two oil injection branches are closed, the main oil pump supplies oil to the diaphragm valve and the emergency trip pipeline, and the oil filling valve of the oil filling pipeline is closed. The method includes Control the closure of one of the critical isolation branches; Controlling the fuel injection branch corresponding to the emergency cutoff branch to be turned on, triggering the fuel injection branch to inject fuel; After the injection is completed, the oil filling valve is gradually opened after the reset solenoid valve is operated until the oil pressure in the emergency trip branch reaches the preset oil pressure value, and then the oil filling valve is closed; Controlling the emergency tripping branch to be turned on; Repeat all the above steps to control another critical trip branch for testing.

9. The emergency shutoff test method according to claim 8, characterized in that: The emergency shutoff branch includes an emergency shutoff device and a cut-off solenoid valve; the emergency shutoff device is connected to the reset solenoid valve, and the cut-off solenoid valve is connected between the diaphragm valve and the emergency shutoff device; When the cut-off solenoid valve is controlled to be closed, the emergency tripping branch is closed; When the cut-off solenoid valve is controlled to open, the emergency shut-off branch is connected.

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