A vortex-preventing device for a gas turbine waste heat boiler drum downcomer

Abstract

The utility model discloses a kind of vortex prevention devices of gas turbine waste heat boiler drum downcomer, including the pre-embedded steel plate fixedly installed on the upper portion of downcomer, the upper portion of pre-embedded steel plate is fixedly supported with the isolating plate of cross distribution, isolating plate top end is fixedly installed with round plate, four symmetrical isolation vortex prevention channels are formed between isolating plate, round plate and pre-embedded steel plate.The utility model is by four identical lower steel plate composition cross structure, the internal flow area of downcomer is divided into four parts, simultaneously and the round plate combination after upper portion water directly into downcomer originally, becomes by circumferential division four parts respectively into downcomer, can effectively avoid the situation that vortex is formed at the mouth of downcomer of drum, water level measurement is distorted, improve the reliability of boiler operation.

Description

Technical Field

[0001] This utility model relates to the field of waste heat utilization technology, and in particular to an anti-vortex device for the downcomer pipe of a gas turbine waste heat boiler. Background Technology

[0002] In a combined cycle power plant, the gas turbine waste heat boiler recovers waste heat from the gas turbine exhaust to generate steam that drives the turbine to generate electricity. The waste heat boiler is one of the three main main units in a combined cycle unit, with the steam drum being a crucial component. It serves as the connecting hub for feedwater heating, evaporation, and superheating processes, and is also a key component for maintaining normal water circulation in the boiler. The steam drum downcomer continuously supplies water from the steam drum to the lower header, which in turn supplies the water-cooled walls. The water-cooled walls are heated in the furnace, causing the water in the tubes to steam, thus maintaining normal water circulation in the boiler. This process is primarily controlled by the water level in the steam drum. An excessively high operating water level can lead to superheater tube rupture, while an excessively low operating water level can cause the boiler to dry-burn, also resulting in tube rupture. Maintaining a stable steam drum water level is the most critical part of the boiler control logic during operation. In a combined cycle power plant, the gas turbine waste heat boiler needs to meet requirements such as rapid start-up and frequent load changes.

[0003] In conventional designs, because the downcomer pipe seat is welded directly after the hole is opened on the waste heat boiler drum without the installation of an anti-vortex device, vortices are prone to occur at the downcomer pipe during boiler operation, especially during startup or load change phases. This can cause fluctuations in the drum water level, distort water level measurements, and easily lead to boiler operation accidents. Utility Model Content

[0004] To solve the above-mentioned technical problems, this utility model designs an anti-vortex device for the downcomer pipe of the steam drum of a gas turbine waste heat boiler.

[0005] The present invention adopts the following technical solution: An anti-vortex device for the downcomer of a gas turbine waste heat boiler includes a pre-embedded steel plate fixedly installed on the upper part of the downcomer. An isolation plate arranged in a cross pattern is fixedly supported on the upper part of the pre-embedded steel plate. A circular plate is fixedly installed on the top of the isolation plate. Four symmetrically isolated anti-vortex channels are formed between the isolation plate, the circular plate and the pre-embedded steel plate.

[0006] Preferably, the partition plate is formed by cross-welding four identical lower steel plates.

[0007] Preferably, the diameter of the circular plate is 50 mm larger than the inner diameter of the downcomer.

[0008] Preferably, the height H of the upper edge of the lower steel plate is 1 / 3 of the inner diameter of the downcomer.

[0009] Preferably, the distance D between the lower end of the lower steel plate and the bottom of the downcomer tube is 51 mm.

[0010] Preferably, the gap S between the lower steel plate and the inner wall of the downcomer is 2mm.

[0011] Preferably, the embedded steel plate and the downcomer pipe are welded together.

[0012] Preferably, the circular plate and the lower steel plate are welded together.

[0013] Preferably, the embedded steel plate is a ring-shaped steel plate, and the embedded steel plate and the lower steel plate are welded together.

[0014] Preferably, the lower steel plate has an extension section at its upper part, and the extension section is fixedly supported on the pre-embedded steel plate.

[0015] The beneficial effects of this utility model are: This utility model uses four identical lower steel plates to form a cross structure, which divides the internal flow area of ​​the downcomer into four parts. At the same time, when combined with the upper circular plate, the water that originally entered the downcomer directly downwards is divided into four parts around the circumference and enters the downcomer separately. This can effectively avoid the situation where the steam drum forms eddies at the downcomer opening, which would cause the water level measurement to be distorted, and improve the reliability of boiler operation. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 yes Figure 1 Cross-sectional view along direction A; Figure 3 This is a schematic diagram of the lower steel plate structure of this utility model; In the diagram: 1. Steam drum body, 2. Embedded steel plate, 3. Downcomer pipe, 4. Circular plate, 5. Lower steel plate. Detailed Implementation

[0017] The technical solution of this utility model will be further described in detail below through specific embodiments and with reference to the accompanying drawings: Example: Figures 1-3 As shown, an anti-vortex device for the downcomer of a gas turbine waste heat boiler includes a steam drum body 1 and a downcomer 3 welded to the steam drum body 1. An embedded steel plate 2 is first welded to the downcomer and then heat-treated as a whole with the steam drum. Four identical lower steel plates 5 are assembled into a cross structure and welded, then welded to a circular plate 4. The assembled circular plate 4 and lower steel plates 5 are welded onto the heat-treated embedded steel plate 2. The embedded steel plate 2, steam drum body 1, circular plate 4, and lower steel plates 5 are preferably welded together to ensure a stable and secure connection.

[0018] Both the circular plate 4 and the lower steel plate 5 are steel plates. During manufacturing, the diameter of the circular plate 4 is 50mm larger than the inner diameter of the downcomer 3. The upper edge height H of the lower steel plate 5 is 1 / 3 of the inner diameter of the downcomer 3, and the distance D between the lower end of the lower steel plate 5 and the end of the downcomer 3 is 51mm. The gap S between the lower end of the lower steel plate 3 and the inner wall of the downcomer 3 is 2mm.

[0019] The purpose of forming a cross on the lower steel plate 5 is as follows: Normally, the downcomer has a large diameter, making it easy for a vortex funnel to form at the downcomer inlet. If a vortex funnel forms at the downcomer inlet, the water level inside the steam drum will fluctuate significantly, leading to inaccurate water level measurements and potentially causing boiler malfunctions. Forming a cross divides the flow area of ​​the downcomer 3 into four parts, effectively preventing the formation of vortices and thus avoiding fluctuations in the steam drum water level, thereby improving the reliability of boiler operation.

[0020] The embodiments described above are merely preferred solutions of this utility model and are not intended to limit this utility model in any way. Other variations and modifications are possible without departing from the technical solutions described in the claims.

Claims

1. A vortex-preventing device for a downcomer of a steam drum of a waste-heat boiler of a combustion engine, characterized in that It includes a pre-embedded steel plate fixedly installed on the upper part of the downcomer pipe, an isolation plate arranged in a cross pattern fixedly supported on the upper part of the pre-embedded steel plate, a circular plate fixedly installed on the top of the isolation plate, and four symmetrical isolation anti-vortex channels formed between the isolation plate, the circular plate and the pre-embedded steel plate.

2. A vortex-preventing device for a drum downcomer of a waste-heat boiler of a combustion engine according to claim 1, characterized in that The isolation plate is formed by welding four identical lower steel plates together in a cross shape.

3. A vortex-preventing device for a drum downcomer of a waste-heat boiler of a combustion engine according to claim 1, characterized in that The diameter of the circular plate is 50 mm larger than the inner diameter of the downcomer.

4. A vortex-preventing device for a drum downcomer of a waste-heat boiler of a combustion engine according to claim 1, characterized in that The height H of the upper edge of the lower steel plate is 1 / 3 of the inner diameter of the downcomer.

5. A vortex-preventing device for a drum downcomer of a waste-heat boiler of a combustion engine according to claim 1, characterized in that The distance D between the lower end of the lower steel plate and the bottom of the downcomer tube is 51mm.

6. A vortex-preventing device for a drum downcomer of a waste-heat boiler of a combustion engine according to claim 1, characterized in that The gap S between the lower steel plate and the inner wall of the downcomer is 2mm.

7. A vortex-preventing device for a drum downcomer of a waste-heat boiler of a combustion engine according to claim 1, characterized in that The embedded steel plate and the downcomer pipe are connected by welding.

8. A vortex-preventing device for a drum downcomer of a waste-heat boiler of a combustion engine according to claim 1, characterized in that The circular plate and the lower steel plate are welded together.

9. A vortex-preventing device for a drum downcomer of a waste-heat boiler of a combustion engine according to claim 1, characterized in that The embedded steel plate is a ring-shaped steel plate, and the embedded steel plate and the lower steel plate are welded together.

10. A vortex-preventing device for a drum downcomer of a waste-heat boiler of a combustion engine according to claim 1, characterized in that An extension section is provided on the upper part of the lower steel plate, and the extension section is fixedly supported on the pre-embedded steel plate.

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