Medium-pressure outer cylinder flexibly compatible with three-stage and four-stage regenerative steam extraction requirements

Abstract

The invention relates to the technical field of medium-pressure outer cylinders, in particular to a medium-pressure outer cylinder flexibly compatible with three-stage and four-stage regenerative steam extraction requirements, and aims to solve the problem of large pressure loss of steam exhaust cavities of a three-stage medium-pressure outer cylinder and a four-stage medium-pressure outer cylinder. The end adjusting partition plate sleeve and the electric end partition plate sleeve are oppositely arranged in an inner space formed by the medium-pressure outer cylinder upper half and the medium-pressure outer cylinder lower half, each side of the inner space is divided into two medium-pressure steam exhaust cavities which are symmetrically arranged in the front-back direction through the end adjusting partition plate sleeve and the electric end partition plate sleeve, and two steam inlets which are symmetrically arranged in the left-right direction are formed in the top of the medium-pressure outer cylinder upper half. The middle of the bottom of the medium-pressure outer cylinder lower half part is provided with two steam exhaust ports which are symmetrically arranged front and back, the bottom of the medium-pressure outer cylinder lower half part is provided with a first-stage steam extraction port, a second-stage steam extraction port, a third-stage steam extraction port and a fourth-stage steam extraction port, and according to the scheme, key technical support is provided for remarkably improving unit efficiency and reducing power generation coal consumption of a power plant.

Description

Technical Field

[0001] This invention relates to the field of medium-pressure outer cylinder technology, specifically a medium-pressure outer cylinder that is flexibly compatible with the requirements of 3-stage and 4-stage regenerative steam extraction. Background Technology

[0002] Conventional 660MW and above units typically have a three-stage extraction steam capacity in their intermediate-pressure external cylinder. Taking a double reheat unit as an example, this generally corresponds to extraction ports 4, 5, and 6. The intermediate-pressure exhaust chamber of this type of structure is usually small, resulting in significant exhaust pressure loss and thus affecting the overall efficiency of the intermediate-pressure cylinder.

[0003] If the user requires the intermediate-pressure module to use four extraction stages (such as extraction stages 4, 5, 6, and 7), then the extraction port of the intermediate-pressure outer cylinder needs to be redesigned, and the original structure cannot be used. Furthermore, more extraction stages often mean that the user has higher requirements for unit efficiency, including lower unit heat consumption. In this case, the problem of high pressure loss in the original exhaust chamber will become more prominent, especially for double reheat units with critical parameters, where the impact is more significant.

[0004] In summary, both the 3rd-stage and 4th-stage intermediate-pressure outer cylinders suffer from significant pressure loss in the exhaust chamber. Summary of the Invention

[0005] The purpose of this invention is to solve the problem of large pressure loss in the exhaust chamber of the 3rd and 4th stage intermediate-pressure outer cylinders. This invention proposes an intermediate-pressure outer cylinder that is flexible and compatible with the regenerative steam extraction requirements of both 3rd and 4th stages.

[0006] The objective of this invention is achieved as follows: a medium-pressure outer cylinder that is flexible and compatible with the requirements of stage 3 and stage 4 regenerative steam extraction, comprising an upper half of the medium-pressure outer cylinder, a lower half of the medium-pressure outer cylinder, an adjusting end baffle sleeve, and an electrical end baffle sleeve. The upper half of the intermediate-pressure outer cylinder is fixed above the lower half of the intermediate-pressure outer cylinder. The adjusting end partition sleeve and the electric end partition sleeve are arranged opposite each other in the internal space formed by the upper half and the lower half of the intermediate-pressure outer cylinder. The adjusting end partition sleeve and the electric end partition sleeve divide each side of the internal space into two symmetrically arranged intermediate-pressure exhaust chambers. The top of the upper half of the intermediate-pressure outer cylinder has two symmetrically arranged steam inlets. The middle of the bottom of the lower half of the intermediate-pressure outer cylinder has two symmetrically arranged exhaust ports. The bottom of the lower half of the intermediate-pressure outer cylinder has two symmetrically arranged first-stage extraction ports, four symmetrically arranged second-stage extraction ports, two symmetrically arranged third-stage extraction ports, and two symmetrically arranged fourth-stage extraction ports. The first-stage extraction ports and the second-stage extraction ports are located below the space formed between the adjusting end partition sleeve and the electric end partition sleeve. The third-stage extraction ports and the fourth-stage extraction ports are located below the intermediate-pressure exhaust chambers.

[0007] Furthermore, both the bottom of the upper half of the medium-pressure outer cylinder and the top of the lower half of the medium-pressure outer cylinder are provided with a split-face flange, and the split-face flange at the bottom of the upper half of the medium-pressure outer cylinder and the split-face flange at the bottom of the lower half of the medium-pressure outer cylinder are connected by multiple bolts.

[0008] Furthermore, symmetrically arranged lower cylinder claws are provided on the left and right sides of the lower half of the intermediate pressure outer cylinder.

[0009] Furthermore, cylinder electrical terminal guide keys are respectively provided in the middle of the lower right side of the intermediate pressure outer cylinder and the middle of the upper right side of the intermediate pressure outer cylinder.

[0010] Furthermore, symmetrically arranged lifting lugs are provided on the front and rear sides of the bottom half of the upper part of the intermediate pressure outer cylinder and the top half of the lower part of the intermediate pressure outer cylinder.

[0011] Furthermore, a steam extraction pipe is connected to the third-stage extraction port.

[0012] Furthermore, the two symmetrical medium-pressure exhaust chambers on each side form a circular annular chamber.

[0013] Furthermore, the two exhaust ports at the top of the upper half of the intermediate-pressure outer cylinder are connected by a support and positioning structure.

[0014] Furthermore, the first-stage steam extraction port is located at the bottom center of the lower half of the intermediate-pressure outer cylinder.

[0015] Furthermore, the third-stage extraction port is located at the front of the bottom of the lower half of the intermediate-pressure outer cylinder, and the fourth-stage extraction port is located at the rear of the bottom of the lower half of the intermediate-pressure outer cylinder.

[0016] Beneficial effects: This invention successfully overcomes the design limitations of the intermediate-pressure outer cylinder in a 660MW double reheat unit. Through innovative design, a universal intermediate-pressure outer cylinder with low exhaust pressure loss has been developed, which can flexibly accommodate the extraction requirements of stage 3 and stage 4 regenerative steam. This design, without changing the original bearing span, laterally expands the intermediate-pressure exhaust chamber, significantly increasing the exhaust area. Further precise aerodynamic optimization successfully reduces the intermediate-pressure exhaust pressure loss by approximately 1 percentage point. The direct benefit is that, under rated operating conditions, the overall unit heat consumption can be effectively reduced by approximately 5 kJ / kW·h, providing key technical support for significantly improving unit efficiency and reducing power plant coal consumption. This has positive implications for further reducing unit heat consumption and power plant coal consumption. Attached Figure Description

[0017] Figure 1 This is a front view of a medium-pressure outer cylinder that is flexible and compatible with the requirements of 3-stage and 4-stage regenerative steam extraction according to the present invention. Figure 2 This is a left view of a medium-pressure outer cylinder that is flexible and compatible with the requirements of 3-stage and 4-stage regenerative steam extraction according to the present invention. Figure 3This is a top view of a medium-pressure outer cylinder that is flexible and compatible with the requirements of 3-stage and 4-stage regenerative steam extraction according to the present invention. Figure 4 This is a perspective view of a medium-pressure outer cylinder that is flexible and compatible with the requirements of 3-stage and 4-stage regenerative steam extraction according to the present invention. Figure 5 This is a solid cross-sectional view of a medium-pressure outer cylinder that is flexible and compatible with the requirements of 3-stage and 4-stage regenerative steam extraction according to the present invention. Figure 6 This is a cloud diagram showing the streamline distribution of the exhaust chamber of a medium-pressure outer cylinder that is flexible and compatible with the requirements of 3-stage and 4-stage regenerative steam extraction according to the present invention. Detailed Implementation

[0018] Specific implementation method 1: A medium-pressure outer cylinder that is flexible and compatible with the requirements of 3-stage and 4-stage regenerative steam extraction, which includes an upper half of the medium-pressure outer cylinder 16, a lower half of the medium-pressure outer cylinder 17, an adjusting end baffle sleeve 14, and an electric end baffle sleeve 15. The upper half 16 of the intermediate-pressure outer cylinder is fixed above the lower half 17 of the intermediate-pressure outer cylinder. The adjusting end partition sleeve 14 and the electric end partition sleeve 15 are arranged opposite each other in the internal space formed by the upper half 16 and the lower half 17 of the intermediate-pressure outer cylinder. The adjusting end partition sleeve 14 and the electric end partition sleeve 15 divide each side of the internal space into two symmetrically arranged intermediate-pressure exhaust chambers 7. The lower half 17 of the intermediate-pressure outer cylinder has two symmetrically arranged steam inlets 1 at the bottom center. The upper half 16 of the intermediate-pressure outer cylinder has two front and rear steam inlets 1 at the top. The symmetrically arranged exhaust ports 2, the bottom of the lower half 17 of the intermediate pressure outer cylinder is provided with two first-stage extraction ports 3 arranged symmetrically on the left and right, four second-stage extraction ports 4 arranged symmetrically in pairs, two third-stage extraction ports 5 arranged symmetrically on the left and right, and two fourth-stage extraction ports 6 arranged symmetrically on the left and right. The first-stage extraction ports 3 and the second-stage extraction ports 4 are located below the space formed between the adjusting end partition sleeve 14 and the electric end partition sleeve 15. The third-stage extraction ports 5 and the fourth-stage extraction ports 6 are located below the intermediate pressure exhaust chamber 7.

[0019] In this embodiment: when the medium-pressure module requires three-stage extraction steam corresponding to extraction steam #4, #5, and #6, the first-stage extraction port is used for extraction steam #4, the second-stage extraction port is used for extraction steam #5, and the third and fourth-stage extraction ports are used for extraction steam #6 simultaneously; when the medium-pressure module requires four-stage extraction steam corresponding to extraction steam #4, #5, #6, and #7, the first-stage extraction port is used for extraction steam #4, the second-stage extraction port is used for extraction steam #5, the third-stage extraction port, through the extraction steam insertion pipe, directly draws steam from the regulating end baffle sleeve and the electrical end baffle sleeve with extraction steam chambers for extraction steam #6, and the fourth-stage extraction port is used for extraction steam #7, thus simultaneously meeting the requirements of either three-stage or four-stage extraction steam.

[0020] Other implementation methods are the same as those in Specific Implementation Method 1.

[0021] Specific implementation method 2: A medium-pressure outer cylinder that is flexible and compatible with the requirements of stage 3 and stage 4 regenerative steam extraction. The bottom of the upper half 16 and the top of the lower half 17 of the medium-pressure outer cylinder are provided with a center-parting flange 11. The center-parting flange 11 at the bottom of the upper half 16 and the center-parting flange 11 at the lower half 17 of the medium-pressure outer cylinder are connected by multiple bolts.

[0022] Other implementation methods are the same as those in Specific Implementation Method 1.

[0023] Specific implementation method three: A medium-pressure outer cylinder that is flexible and compatible with the regenerative steam extraction requirements of stage 3 and stage 4, wherein the lower half of the medium-pressure outer cylinder 17 is provided with symmetrically arranged lower half cylinder cat claws 9 on the left and right sides of the top.

[0024] Other implementation methods are the same as those in Specific Implementation Method 1.

[0025] Specific implementation method four: A medium-pressure outer cylinder that is flexible and compatible with the requirements of stage 3 and stage 4 regenerative steam extraction, wherein the middle part of the right side of the lower half 17 of the medium-pressure outer cylinder and the middle part of the right side of the upper half 16 of the medium-pressure outer cylinder are respectively provided with cylinder electrical terminal guide keys 10.

[0026] Other implementation methods are the same as those in Specific Implementation Method 1.

[0027] Specific implementation method five: A medium-pressure outer cylinder that is flexible and compatible with the requirements of stage 3 and stage 4 regenerative steam extraction, wherein the bottom of the upper half 16 of the medium-pressure outer cylinder and the top of the lower half 17 of the medium-pressure outer cylinder are respectively provided with symmetrically arranged lifting lugs 12 on the front and rear sides.

[0028] In this embodiment: the lifting lugs are used for lifting and turning the medium-pressure outer cylinder.

[0029] Other implementation methods are the same as those in Specific Implementation Method 1.

[0030] Specific implementation method six: A medium-pressure outer cylinder that is flexible and compatible with the requirements of 3-stage and 4-stage regenerative steam extraction, wherein a steam extraction pipe 13 is connected to the third-stage steam extraction port 5.

[0031] In this embodiment: the third-stage extraction port directly draws steam from the regulating end baffle sleeve and the electrical end baffle sleeve, which have extraction chambers, by means of an extraction steam insertion pipe.

[0032] Other implementation methods are the same as those in Specific Implementation Method 1.

[0033] Specific implementation method seven: A medium-pressure outer cylinder that is flexible and compatible with the regenerative steam extraction requirements of stage 3 and stage 4, with two symmetrical medium-pressure exhaust chambers 7 on each side forming a similar circular annular chamber.

[0034] In this embodiment, the exhaust chamber was laterally expanded to nearly a full circle, effectively increasing the exhaust area and reducing pressure loss. Other implementation methods are the same as those in Specific Implementation Method 1.

[0035] Specific implementation method eight: A medium-pressure outer cylinder that is flexible and compatible with the requirements of stage 3 and stage 4 regenerative steam extraction, wherein the two exhaust ports 2 at the top of the upper half 16 of the medium-pressure outer cylinder are connected by a support and positioning structure 8.

[0036] Other implementation methods are the same as those in Specific Implementation Method 1.

[0037] Specific implementation method nine: A medium-pressure outer cylinder that is flexible and compatible with the requirements of 3-stage and 4-stage regenerative steam extraction, wherein the first-stage steam extraction port 3 is located at the bottom middle of the lower half 17 of the medium-pressure outer cylinder.

[0038] Other implementation methods are the same as those in Specific Implementation Method 1.

[0039] Specific Implementation Method 10: A medium-pressure outer cylinder that is flexible and compatible with the requirements of 3-stage and 4-stage regenerative steam extraction, wherein the third-stage steam extraction port 5 is located at the front of the bottom end of the lower half 17 of the medium-pressure outer cylinder, and the fourth-stage steam extraction port 6 is located at the rear of the bottom end of the lower half 17 of the medium-pressure outer cylinder.

[0040] Other implementation methods are the same as those in Specific Implementation Method 1.

[0041] Working principle: When the unit is running, the secondary reheat steam passes through the intermediate pressure valve and enters the intermediate pressure flow passage from the intermediate pressure steam inlet at the bottom of the intermediate pressure outer cylinder. It first performs work through the various pressure stages installed on the intermediate pressure inner cylinder, adjusting end baffle sleeve, electrical end baffle sleeve, and intermediate pressure rotor, and finally exits through the two symmetrical intermediate pressure exhaust ports on the intermediate pressure outer cylinder. For the flow passage, there are two completely symmetrical flow channels, i.e., double flow splitting. This design concept realizes the thrust self-balancing of the intermediate pressure module and has high stability.

[0042] When the medium-pressure module requires three stages of steam extraction (corresponding to extraction ports #4, #5, and #6), the first-stage extraction port is used for extraction port #4, the second-stage port for extraction port #5, and both the third and fourth-stage extraction ports are used for extraction port #6. When the medium-pressure module requires four stages of steam extraction (corresponding to extraction ports #4, #5, #6, and #7), the first-stage extraction port is used for extraction port #4, the second-stage port for extraction port #5, and the third-stage port, via an extraction pipe, directly draws steam from the regulating end baffle sleeve and electrical end baffle sleeve with extraction chambers for extraction port #6. The fourth-stage extraction port is used for extraction port #7. This simultaneously meets the requirements of either three or four stages of steam extraction. Furthermore, all the extraction ports employ a symmetrical design, significantly improving the unit's operational stability. See [link to relevant documentation]. Figure 1 .

[0043] The dual-flow intermediate-pressure outer cylinder is designed with four symmetrical exhaust chambers and two symmetrical upper exhaust ports at each end. This invention laterally expands the exhaust chambers to nearly a full circle, effectively increasing the exhaust area and reducing pressure loss. Combined with aerodynamic optimization, this reduces the intermediate-pressure exhaust pressure loss by approximately 1 percentage point, resulting in a reduction of approximately 5 kJ / kW·h in overall unit heat consumption under rated operating conditions. This innovation has positive implications for further reducing unit heat consumption and power plant coal consumption. See [link to relevant documentation] Figure 2 , Figure 5 , Figure 6 .

[0044] This invention, targeting a 660MW double reheat unit, innovatively designs the intermediate-pressure outer cylinder, achieving a universal, low-exhaust-pressure-loss intermediate-pressure outer cylinder that simultaneously meets the extraction requirements of both stage 3 and stage 4 regenerative steam. The core of this design lies in: laterally expanding the intermediate-pressure exhaust chamber within the existing bearing span limitations to increase the exhaust flow area, and combining this with aerodynamic optimization calculations to reduce the intermediate-pressure exhaust pressure loss by approximately 1 percentage point. Under rated operating conditions, this improvement can reduce the overall unit heat consumption by approximately 5 kJ / kW·h. This innovation has positive implications for further reducing unit heat consumption and power plant coal consumption.

Claims

1. A medium-pressure outer cylinder that is flexibly compatible with the requirements of 3-stage and 4-stage regenerative steam extraction, characterized in that: It includes the upper half (16) of the medium-pressure outer cylinder, the lower half (17) of the medium-pressure outer cylinder, the adjusting end partition sleeve (14) and the electrical end partition sleeve (15). The upper half (16) of the intermediate-pressure outer cylinder is fixed above the lower half (17) of the intermediate-pressure outer cylinder. The adjusting end partition sleeve (14) and the electric end partition sleeve (15) are arranged opposite to each other in the internal space formed by the upper half (16) and the lower half (17) of the intermediate-pressure outer cylinder. The adjusting end partition sleeve (14) and the electric end partition sleeve (15) divide each side of the internal space into two symmetrically arranged intermediate-pressure exhaust chambers (7). The top of the upper half (16) of the intermediate-pressure outer cylinder is provided with two symmetrically arranged steam inlets (1), and the bottom of the lower half (17) of the intermediate-pressure outer cylinder is provided with two symmetrically arranged steam inlets (1). The exhaust port (2) is provided. The bottom of the lower half (17) of the intermediate pressure outer cylinder is provided with two first-stage extraction ports (3) arranged symmetrically on the left and right, four second-stage extraction ports (4) arranged symmetrically in pairs, two third-stage extraction ports (5) arranged symmetrically on the left and right, and two fourth-stage extraction ports (6) arranged symmetrically on the left and right. The first-stage extraction ports (3) and the second-stage extraction ports (4) are located below the space formed between the adjusting end partition sleeve (14) and the electric end partition sleeve (15). The third-stage extraction ports (5) and the fourth-stage extraction ports (6) are located below the intermediate pressure exhaust chamber (7).

2. The medium-pressure outer cylinder that is flexibly compatible with the requirements of stage 3 and stage 4 regenerative steam extraction, as described in claim 1, is characterized in that: A split flange (11) is provided at the bottom of the upper half (16) and the top of the lower half (17) of the medium-pressure outer cylinder. The split flange (11) at the bottom of the upper half (16) and the split flange (11) at the lower half (17) of the medium-pressure outer cylinder are connected by multiple bolts.

3. The medium-pressure outer cylinder that is flexibly compatible with the requirements of stage 3 and stage 4 regenerative steam extraction, as described in claim 1, is characterized in that: The lower half of the medium-pressure outer cylinder (17) is provided with symmetrically arranged lower cylinder claws (9) on the left and right sides of the top.

4. The medium-pressure outer cylinder that is flexibly compatible with the requirements of stage 3 and stage 4 regenerative steam extraction, as described in claim 1, is characterized in that: A cylinder electrical terminal guide key (10) is provided on the middle part of the right side of the lower half (17) of the medium-pressure outer cylinder and the middle part of the right side of the upper half (16) of the medium-pressure outer cylinder.

5. A medium-pressure outer cylinder that is flexibly compatible with the requirements of stage 3 and stage 4 regenerative steam extraction, as described in claim 1, is characterized in that: Symmetrically arranged lifting lugs (12) are provided on the bottom of the upper half (16) of the medium-pressure outer cylinder and the top of the lower half (17) of the medium-pressure outer cylinder.

6. The medium-pressure outer cylinder that is flexibly compatible with the requirements of stage 3 and stage 4 regenerative steam extraction as described in claim 1, characterized in that: The third-stage extraction port (5) is connected to an extraction pipe (13).

7. A medium-pressure outer cylinder that is flexibly compatible with the requirements of stage 3 and stage 4 regenerative steam extraction, as described in claim 1, is characterized in that: Two symmetrical medium-pressure exhaust chambers (7) on each side form a circular annular chamber.

8. A medium-pressure outer cylinder that is flexibly compatible with the requirements of stage 3 and stage 4 regenerative steam extraction, as described in claim 1, is characterized in that: The two exhaust ports (2) at the top of the upper half (16) of the medium-pressure outer cylinder are connected by a support and positioning structure (8).

9. A medium-pressure outer cylinder that is flexibly compatible with the requirements of stage 3 and stage 4 regenerative steam extraction, as described in claim 1, is characterized in that: The first-stage extraction port (3) is located at the bottom middle of the lower half (17) of the intermediate-pressure outer cylinder.

10. A medium-pressure outer cylinder that is flexibly compatible with the requirements of stage 3 and stage 4 regenerative steam extraction, as described in claim 1, is characterized in that: The third-stage extraction port (5) is located at the front of the bottom of the lower half (17) of the intermediate-pressure outer cylinder, and the fourth-stage extraction port (6) is located at the rear of the bottom of the lower half (17) of the intermediate-pressure outer cylinder.

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