System for adjusting low-temperature reheated steam to auxiliary steam
By designing a dual-path regulating system, combining the main and bypass regulating pipelines, the problem of insufficient regulation accuracy of the low-temperature reheat steam to auxiliary steam system under different operating conditions is solved, realizing the stability and precise control of steam parameters. This is suitable for the retrofitting of steam turbine units and new equipment, and reduces costs.
Patent Information
- Application Number
- CN202520789554.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-24
- Publication Date
- 2026-01-16
- Estimated Expiration
- 2035-04-24
AI Technical Summary
The existing low-temperature reheat steam to auxiliary steam system has a low valve opening and insufficient regulation accuracy when the steam supply demand is small, resulting in unstable steam parameters and difficulty in meeting the requirements for precise regulation. Especially during the start-up and normal operation of the unit, the control characteristics are poor and the working fluid loss is large.
The system adopts a dual-path regulating system design, including a main regulating pipeline and a bypass regulating pipeline. The main pipeline is adapted to high flow rate requirements, while the bypass pipeline is adapted to low flow rate requirements. Through the combination of the main regulating valve and the bypass regulating valve, precise flow control under different operating conditions can be achieved. Combined with condensate collection and protection valves, the stability of steam parameters is ensured.
It enables precise adjustment of auxiliary steam demand under different operating conditions, reduces the instability of downstream steam parameters, improves the system's adjustment depth and control accuracy, reduces working fluid loss, is suitable for both new and old equipment retrofitting, and lowers costs.
Smart Images
Figure CN223806193U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of steam turbine steam regulation, and particularly relates to a low-temperature reheat steam to auxiliary steam regulation system. BACKGROUND
[0002] Under different working conditions of unit start-up and normal operation, each auxiliary steam use point has different requirements for steam quantity. The low-temperature reheat steam to auxiliary steam adopts a single-path regulation system, and when the steam demand is small, the valve opening is low. However, the valve opening cannot meet the accurate regulation of the steam demand, and the steam parameter after the valve is unstable, and the regulation value and the target value have a large deviation.
[0003] The auxiliary steam of a gas-steam combined cycle unit is generally obtained from a start-up boiler (or an adjacent unit) or low-temperature reheat steam pipeline pressure reduction. In the early stage of the start-up phase, the auxiliary steam demand is large, and the low-temperature reheat steam pressure reduction to the auxiliary steam system has a large steam quantity. In the normal operation phase of the unit, the auxiliary steam demand is small, and the low-temperature reheat steam pressure reduction to the auxiliary steam system has a small steam quantity. If the low-temperature reheat steam to auxiliary steam system is designed and operated according to the conventional method, the control characteristics of the regulation valve are poor in the normal operation phase, and the working medium loss is large. CONTENT OF THE INVENTION
[0004] The application aims to provide a low-temperature reheat steam to auxiliary steam regulation system, which adopts a double-path regulation system design, can ensure excellent flow control characteristics of the valve, stable steam parameter after the valve, and accurate regulation when the steam demand is large or small.
[0005] The application achieves the above-mentioned purpose by the following technical scheme.
[0006] A low-temperature reheat steam to auxiliary steam regulation system, comprising a low-temperature reheat steam source, the low-temperature reheat steam source being in communication with a steam supply pipeline, the steam supply pipeline being in communication with an auxiliary steam system, a middle section of the steam supply pipeline being divided into a main-path regulation pipeline and a bypass regulation pipeline in parallel, a main-path regulation valve being arranged on the main-path regulation pipeline, a bypass regulation valve being arranged on the bypass regulation pipeline, a flow area ratio of the main-path regulation pipeline to the bypass regulation pipeline being (5-15):1, a linear regulation range of the main-path regulation valve being Q-100% of a maximum steam demand of the auxiliary steam, a linear regulation range of the bypass regulation valve being 0%-Q of the maximum steam demand of the auxiliary steam, and Q being 2%-20%.
[0007] Further, the flow area ratio of the main-path regulation pipeline to the bypass regulation pipeline is (8-12):1, and Q is 4%-6%.
[0008] Further, a main-path shutoff valve is arranged on the main-path regulation pipeline, and a bypass shutoff valve is arranged on the bypass regulation pipeline.
[0009] Further, the main path shutoff valve is an electric valve located in front of the main path regulating valve, and the bypass shutoff valve is an electric valve located in front of the bypass regulating valve and a manual valve located behind the bypass regulating valve.
[0010] Further, the rear section of the steam supply pipeline is provided with a safety valve, a steam exhaust shutoff valve and a check valve.
[0011] Further, the safety valve, the steam exhaust shutoff valve and the check valve are arranged in sequence along the flow direction of the steam supply pipeline, and the steam exhaust shutoff valve is a manual valve.
[0012] Further, the front section of the steam supply pipeline is provided with a drain collector, the drain collector is communicated with a low-position drain pipeline, and the low-position drain pipeline is communicated with a drain collection device.
[0013] Further, the middle section of the low-position drain pipeline is divided into a non-power drain pipeline and a power drain pipeline in parallel, a non-power drain valve is arranged on the non-power drain pipeline, and a power drain valve is arranged on the power drain pipeline.
[0014] Further, the non-power drain pipeline is further provided with a drain shutoff valve.
[0015] Further, the drain shutoff valve is a manual valve located in front of and behind the non-power drain valve.
[0016] The beneficial effects of the present application are as follows:
[0017] (1) Two regulating pipelines with different regulating capacities are adopted, and the regulating pipeline with corresponding capacity is selected according to different low-temperature reheat steam demand, which is suitable for steam turbine units with large difference in auxiliary steam demand under different working conditions.
[0018] (2) The regulating system is simple in structure and easy to design and operate, and does not need complex design or large modification and repair, thereby saving cost and reducing cost.
[0019] (3) After the regulating system is adopted, the regulating depth of low-temperature reheat steam to the auxiliary steam system can be better improved, and the stability of the medium parameters after the valve under the steam supply demand can be ensured.
[0020] The foregoing main scheme of the present application and each further selection scheme thereof can be freely combined to form multiple schemes, all of which are the schemes that can be adopted and claimed by the present application; and the present application can also be freely combined between (each non-conflicting selection) and between other selections. Those skilled in the art can understand that there are multiple combinations according to the existing technology and common knowledge after understanding the present scheme, and all of them are the technical schemes to be protected by the present application, which will not be listed exhaustively. BRIEF DESCRIPTION OF DRAWINGS
[0021] Figure 1 is a structural schematic diagram of the present application.
[0022] In the figure: 1-low temperature reheat steam source, 2-steam supply pipeline, 3-main path adjustment pipeline, 4-bypass adjustment pipeline, 5-assistant steam system, 6-drainage collector, 7-low position drainage pipeline, 8-drainage collection equipment, 9-main path shutoff valve, 10-main path adjustment valve, 11-bypass shutoff valve, 12-bypass adjustment valve, 13-safety valve, 14-exhaust shutoff valve, 15-check valve, 16-non-power drainage pipeline, 17-power drainage pipeline, 18-drainage shutoff valve, 19-non-power drainage valve, 20-power drainage valve. DETAILED DESCRIPTION
[0023] The present application will be further described below in conjunction with specific embodiments and the accompanying drawings.
[0024] EMBODIMENT
[0025] REFERENCE Figure 1 As shown in the figure, a low temperature reheat steam to assistant steam adjustment system comprises a low temperature reheat steam source 1, a steam supply pipeline 2, a main path adjustment pipeline 3, a bypass adjustment pipeline 4, an assistant steam system 5, a drainage collector 6, a low position drainage pipeline 7, drainage collection equipment 8, a main path shutoff valve 9, a main path adjustment valve 10, a bypass shutoff valve 11, a bypass adjustment valve 12, a safety valve 13, an exhaust shutoff valve 14, a check valve 15, a non-power drainage pipeline 16, a power drainage pipeline 17, a drainage shutoff valve 18, a non-power drainage valve 19 and a power drainage valve 20.
[0026] The low temperature reheat steam source 1 is a supply source of low temperature reheat steam, and the low temperature reheat steam source 1 is in communication with the steam supply pipeline 2, the steam supply pipeline 2 is in communication with the assistant steam system 5, and the steam supply pipeline 2 provides steam to the assistant steam system 5.
[0027] The middle section of the steam supply pipeline 2 is divided into the main path adjustment pipeline 3 and the bypass adjustment pipeline 4 in parallel, the main path adjustment pipeline 3 is provided with the main path adjustment valve 10, and the bypass adjustment pipeline 4 is provided with the bypass adjustment valve 12. When the assistant steam demand is large, the steam flows through the main path adjustment pipeline 3 and is regulated by the main path adjustment valve 10 under large flow. When the assistant steam demand is small, the steam flows through the bypass adjustment pipeline 4 and is regulated by the bypass adjustment valve 12 under small flow.
[0028] The flow area ratio of the main path adjustment pipeline 3 to the bypass adjustment pipeline 4 is (5-15): 1, and preferably (8-12): 1, that is, the main path adjustment pipeline 3 is suitable for large flow steam transportation, and the bypass adjustment pipeline 4 is suitable for small flow steam transportation.
[0029] The linear adjustment range of the main path adjustment valve 10 is Q~100% of the maximum steam demand of the auxiliary steam, and the linear adjustment range of the bypass adjustment valve 12 is 0%~Q of the maximum steam demand of the auxiliary steam, Q is 2%~20%, preferably 4%~6%, that is, the main path adjustment valve 10 is suitable for large-flow steam regulation, and the bypass adjustment valve 12 is suitable for small-flow steam regulation. Through different pipelines and adjustment valves of the main path and the bypass, different steam demands are adapted to ensure accurate adjustment and delivery of steam.
[0030] The main path adjustment pipeline 3 is also provided with a main path shutoff valve 9 for shutoff or communication of the main path, realizing switching of the main path and the bypass, and the main path shutoff valve 9 is preferably an electric valve located in front of the main path adjustment valve 10.
[0031] The bypass adjustment pipeline 4 is also provided with a bypass shutoff valve 11 for shutoff or communication of the bypass, realizing switching of the main path and the bypass, and the bypass shutoff valve 11 is preferably an electric valve located in front of the bypass adjustment valve 12 and a manual valve located behind the bypass adjustment valve 12.
[0032] When the steam demand of the auxiliary steam point is large (Q and above the maximum steam demand of the auxiliary steam), the bypass electric valve and the electric adjustment valve are closed, the main path electric valve and the electric adjustment valve are opened, and the low-temperature reheat steam is adjusted through the main path and then reaches the auxiliary steam system.
[0033] When the steam demand of the auxiliary steam point is small (Q and below the maximum steam demand of the auxiliary steam), the main path electric valve and the electric adjustment valve are closed, the bypass electric valve and the electric adjustment valve are opened, the adjustment depth of the low-temperature reheat steam to the auxiliary steam system is improved, the stability of the medium parameters after the valve under low steam supply demand is ensured, and the low-temperature reheat steam is adjusted through the bypass and then reaches the auxiliary steam system.
[0034] The rear section of the steam supply pipeline 2 is provided with a safety valve 13, a steam shutoff valve 14 and a check valve 15, which are arranged in sequence along the flow direction of the steam supply pipeline 2. When the pressure in the steam supply pipeline 2 is too high, the safety valve 13 automatically jumps to release pressure protection. The steam shutoff valve 14 is a manual valve, which is used for shutoff or communication of the pipeline when the main path or bypass adjustment valve is overhauled or other needs. The check valve 15 is used to prevent the steam in the auxiliary steam system from flowing backward.
[0035] When the main path and bypass adjustment valves fail and the pressure of the pipeline after the valves exceeds the set value, the safety valve can automatically jump to protect the pipeline from overpressure. The main path and bypass adjustment valves are merged into one pipeline to the auxiliary steam system, which is unidirectional, the low-temperature reheat steam can be adjusted and then reaches the auxiliary steam system, and the auxiliary steam system cannot flow back to the low-temperature reheat steam system.
[0036] The front section of the steam supply pipeline 2 is provided with a drain collector 6, the drain collector 6 is communicated with a low-position drain pipeline 7, the low-position drain pipeline 7 is communicated with a drain collecting device 8, the condensate water in the steam supply pipeline 2 is collected through the drain collector 6, and then is sent to the drain collecting device 8 through the low-position drain pipeline 7 for collection and treatment.
[0037] The middle section of the low-position drain pipeline 7 is divided into a non-power drain pipeline 16 and a power drain pipeline 17 in parallel, the non-power drain pipeline 16 is used for automatic force drain water, and the power drain pipeline 17 is used for external power drain water.
[0038] The non-power drain pipeline 16 is provided with a non-power drain valve 19, the non-power drain valve 19 is an automatic force drain valve, that is, can automatically identify steam and water, and realizes automatic steam blocking and water drainage. The non-power drain pipeline 16 is provided with a power drain valve 20, the power drain valve 20 realizes steam blocking and water drainage through external power.
[0039] The non-power drain pipeline 16 is also provided with a drain shutoff valve 18, which is used for cutting off or connecting the pipeline, realizing switching of the pipeline, and the drain shutoff valve 18 is preferably a manual valve located in front of and behind the non-power drain valve 19.
[0040] The drain collector 6 and the low-position drain pipeline 7 are arranged at the lowest point in front of the main road or bypass shutoff valve of the steam supply pipeline 2, for timely transporting the accumulated water in the pipeline section, avoiding water storage in the pipeline. According to the arrangement, multiple low-position drain pipelines can be needed. The pipeline is provided with a drain collector, which is convenient for collecting the drain water in the pipeline.
[0041] The automatic drain valve (non-power control) arranged on the drain pipeline can timely and automatically transport the drain water. The drain valve (power control) as a backup can also be interlocked with a temperature measuring point, and according to the signal fed back by the temperature measuring point, interlocking switching is performed.
[0042] The foregoing basic examples and each further selected example of the present application can be freely combined to form multiple embodiments, which are all embodiments that can be adopted and claimed by the present application. In the present application scheme, each selected example can be arbitrarily combined with any basic example and selected example.
[0043] The above only describes the preferred embodiments of the present application and does not limit the present application, and any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims
1. A low temperature reheat steam to auxiliary steam conditioning system comprising a source of low temperature reheat steam (1) characterised in that: The low-temperature reheat steam source (1) is communicated with a steam supply pipeline (2), the steam supply pipeline (2) is communicated with an auxiliary steam system (5), a middle section of the steam supply pipeline (2) is divided into a main pipeline adjusting pipeline (3) and a bypass pipeline adjusting pipeline (4) in parallel, the main pipeline adjusting pipeline (3) is provided with a main pipeline adjusting valve (10), the bypass pipeline adjusting pipeline (4) is provided with a bypass pipeline adjusting valve (12), a flow area ratio of the main pipeline adjusting pipeline (3) to the bypass pipeline adjusting pipeline (4) is (5-15):1, a linear adjusting range of the main pipeline adjusting valve (10) is Q-100% of a maximum steam demand of the auxiliary steam, a linear adjusting range of the bypass pipeline adjusting valve (12) is 0%-Q of the maximum steam demand of the auxiliary steam, and Q is 2%-20%.
2. The cryogenic reheat steam to auxiliary steam conditioning system of claim 1, wherein: The flow area ratio of the main pipeline adjusting pipeline (3) to the bypass pipeline adjusting pipeline (4) is (8-12):1, and Q is 4%-6%.
3. The cryogenic reheat steam to auxiliary steam conditioning system of claim 1, wherein: The main pipeline adjusting pipeline (3) is further provided with a main pipeline shutoff valve (9), and the bypass pipeline adjusting pipeline (4) is further provided with a bypass pipeline shutoff valve (11).
4. The cryogenic reheat steam to auxiliary steam conditioning system of claim 3, wherein: The main pipeline shutoff valve (9) is an electric valve located in front of the main pipeline adjusting valve (10), and the bypass pipeline shutoff valve (11) is an electric valve located in front of the bypass pipeline adjusting valve (12) and a manual valve located behind the bypass pipeline adjusting valve (12).
5. The cryogenic reheat steam to auxiliary steam conditioning system of claim 1, wherein: A rear section of the steam supply pipeline (2) is provided with a safety valve (13), a steam discharge shutoff valve (14) and a check valve (15).
6. The cryogenic reheat steam to auxiliary steam conditioning system of claim 5, wherein: The safety valve (13), the steam discharge shutoff valve (14) and the check valve (15) are arranged in sequence along a flow direction of the steam supply pipeline (2), and the steam discharge shutoff valve (14) is a manual valve.
7. The cryogenic reheat steam to auxiliary steam conditioning system of claim 1, wherein: A front section of the steam supply pipeline (2) is provided with a drain collector (6), the drain collector (6) is communicated with a low-position drain pipeline (7), and the low-position drain pipeline (7) is communicated with a drain collecting device (8).
8. The cryogenic reheat steam to auxiliary steam conditioning system of claim 7, wherein: A middle section of the low-position drain pipeline (7) is divided into a non-power drain pipeline (16) and a power drain pipeline (17) in parallel, the non-power drain pipeline (16) is provided with a non-power drain valve (19), and the power drain pipeline (17) is provided with a power drain valve (20).
9. The cryogenic reheat steam to auxiliary steam conditioning system of claim 8, wherein: The non-power drain pipeline (16) is further provided with a drain shutoff valve (18).
10. The cryogenic reheat steam to auxiliary steam conditioning system of claim 9, wherein: The drain shutoff valve (18) is a manual valve located in front of and behind the non-power drain valve (19).