50MW supercritical CO2 axial flow turbine with volute air inflow function

Abstract

The invention relates to a 50MW supercritical CO2 axial flow turbine with a volute for air inflow. Supercritical carbon dioxide circulation has become one of hot-spot technologies in the field of energy and power by virtue of the advantages of high thermal efficiency, high compactness, high economic-environmental protection property and the like. The high-pressure air compressor comprises a front bearing box, a rear bearing box, a high-pressure cylinder and a rotor, the high-pressure cylinder is of a double-layer cylinder structure and comprises a high-pressure inner cylinder and a high-pressure outer cylinder, the two sides of the high-pressure outer cylinder are connected with the bearing boxes through positioning cat claws, and an air inlet of the high-pressure cylinder is connected with a main steam adjusting combined valve; blades on the rotor are of a multi-stage small enthalpy drop reaction type structure. The 50MW supercritical CO2 axial flow turbine is used for volute air inlet.

Description

Technical Field

[0001] The invention relates to a 50MW supercritical CO2 axial flow turbine with volute air intake. Background Art

[0002] In the context of the dual carbon goals, traditional technologies can no longer meet the requirements of current energy transformation in terms of improving energy efficiency and unit flexibility. Today's power industry urgently needs to develop new, efficient and flexible thermal power generation technologies with revolutionary significance to support the grid connection of a high proportion of renewable energy, which is of great significance to the construction of a new power system and the realization of dual carbon goals. Supercritical carbon dioxide cycle has become one of the hot technologies in the field of energy and power due to its advantages of high thermal efficiency, high compactness and economic and environmental protection. Summary of the invention

[0003] The purpose of the present invention is to solve the above-mentioned problems and to provide a 50MW supercritical CO2 axial flow turbine with volute air intake.

[0004] The above purpose is achieved through the following technical solutions: A 50MW supercritical CO2 axial flow turbine with volute air intake, comprising: a front bearing box, a rear bearing box, a high-pressure cylinder and a rotor, wherein the high-pressure cylinder is a double-layer cylinder structure, comprising a high-pressure inner cylinder and a high-pressure outer cylinder, both sides of the high-pressure outer cylinder are connected to the bearing box through positioning cat claws, and the air inlet of the high-pressure cylinder is connected to the main steam regulating combined valve; The blades on the rotor adopt a multi-stage small enthalpy drop reaction structure.

[0005] The 50MW supercritical CO2 axial flow turbine with volute air intake is provided with a thrust support bearing in the rear bearing box, which is the relative dead point of expansion of the unit. The rear bearing box is fixed to the foundation by anchor bolts, which is the absolute dead point of expansion of the entire unit.

[0006] The 50MW supercritical CO2 axial flow turbine with volute air intake has a heat insulation plate fixed between the high-pressure inner cylinder and the dry gas seal to form a heat insulation cavity structure.

[0007] The 50MW supercritical CO2 axial flow turbine with volute air intake, the stationary blades and moving blades of the rotor adopt a pre-twisted assembled structure.

[0008] The 50MW supercritical CO2 axial flow turbine with volute air intake, the positioning cat claw includes a cat claw, the cat claw has a positioning key groove, and the positioning key groove is clearance-matched with the positioning key installed on the corresponding side bearing box.

[0009] The 50MW supercritical CO2 axial flow turbine with volute air intake has a high-pressure outer cylinder with a cylindrical structure, no center dividing surface, and is vertically divided into three sections.

[0010] The 50MW supercritical CO2 axial flow turbine with volute air intake, the high-pressure inner cylinder adopts a barrel-type inner cylinder and a red sleeve ring sealing structure. Beneficial Effects

[0011] 1. The two main steam regulating combined valves of the present invention are respectively connected to the 2×180° volute air inlets of the two high-pressure cylinders, and the unit flow adopts a multi-stage small enthalpy drop reaction design, which fundamentally improves the flow efficiency.

[0012] 2. The moving blades and stationary blades of the present invention adopt a pre-twisted assembly structure to avoid welding deformation and improve flow accuracy and turbine efficiency.

[0013] 3. In the present invention, a heat insulation plate is fixed between the high-pressure inner cylinder and the dry gas seal to form a heat insulation cavity structure, which is combined with cold air injection to reduce the temperature of the shaft end and ensure the long-term reliable operation of the dry gas seal.

[0014] 4. The high-pressure outer cylinder of the present invention is connected to the bearing box by a cat's claw and a positioning key structure, which is mature and stable and can well meet the expansion requirements of the unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Attached Figure 1 is a longitudinal sectional view of the present invention; Attached Figure 2 It is a front view of the present invention; Attached Figure 3 is a top view of the present invention; Attached Figure 4 It is a structural diagram of the sliding pin system of the present invention; Attached Figure 5 It is a schematic diagram of the positioning key structure; Attached Figure 6 It is a schematic diagram of the reaction blade structure; Attached Figure 7 This is a schematic diagram of the direct connection between the main steam regulating combined valve and the high-pressure cylinder; In the figure: 1. front bearing box; 2. high-pressure outer cylinder; 3. high-pressure inner cylinder; 4. rotor; 5. rear bearing box; 6. heat insulation board; 7. cat's claw; 8. positioning keyway; 9. positioning key; 10. thrust bearing; 11. high-pressure cylinder; 12. moving blades; 13. stationary blades; 14. main steam regulating combined valve. DETAILED DESCRIPTION

[0016] Reference Figure 1-Figure 7This unit uses CO2 as the working fluid, with a single-stage turbine, forming a high-pressure cylinder, and the high-pressure part is a double-layer cylinder structure. It adopts a cylindrical inner cylinder and a red sleeve ring sealing structure. The outer cylinder adopts a cylindrical structure, without a center dividing surface, and is vertically divided into three sections; the dividing surface is at both ends, and is connected by vertical flanges. Cat claw structures are designed on both sides of the outer cylinder, which are supported by the horizontal center dividing surface of the cat claw. There is a positioning keyway 8 on the cat claw. The positioning keyway and the positioning key 9 installed on the bearing box have a small clearance to achieve the axial positioning of the outer cylinder and the bearing box. By adjusting the parameters and structure, the power of the unit is increased to 50MW.

[0017] The flow of this unit is divided into a first-stage turbine. The compressed air enters the high-pressure inner cylinder through the main air regulating combined valve. After flowing through and doing work, it enters the high-pressure outer cylinder and is finally discharged from the lower exhaust port of the outer cylinder.

[0018] A 50MW supercritical CO2 axial flow turbine with volute intake, comprising: a front bearing box 1, a rear bearing box 5, a high-pressure cylinder 11 and a rotor 4. The high-pressure cylinder is a double-layer cylinder structure, including a high-pressure inner cylinder 3 and a high-pressure outer cylinder 2. Both sides of the high-pressure outer cylinder are connected to the bearing box through positioning cat claws. The air inlet of the high-pressure cylinder is connected to the main steam regulating combined valve 14, eliminating the air guide pipe structure. The cylinder is a volute intake, which minimizes the intake loss. Two main steam regulating combined valves are respectively connected to the 2×180° volute intakes of the two high-pressure cylinders. The unit flow adopts a multi-stage small enthalpy drop reaction design, which fundamentally improves the flow efficiency, reduces air flow unevenness and pressure loss, and maximizes energy utilization. The blades on the rotor adopt a multi-stage small enthalpy drop reaction structure.

[0019] The rear bearing box is provided with a thrust support bearing 10, which is the relative dead point of expansion of the unit. The rear bearing box is fixed to the foundation by anchor bolts, which is the absolute dead point of expansion of the entire unit.

[0020] A heat insulation plate 6 is fixed between the high-pressure inner cylinder and the dry gas seal to form a heat insulation cavity structure, which cooperates with the injection of cold air to maintain a low shaft end temperature, thereby ensuring the normal use of the seal and the stability of the equipment operation; The stationary blades and moving blades of the rotor adopt a pre-twisted assembled structure. Compared with the traditional welded partition, the assembled structure has no welds, thus avoiding welding deformation and better ensuring the flow accuracy. The positioning cat claw comprises a cat claw 7, and a positioning key slot 8 is provided on the cat claw. The positioning key slot is clearance-matched with a positioning key 9 installed on the corresponding side bearing box. Through the positioning cat claw, the cylinder and the bearing box expand synchronously, reducing the dynamic expansion difference and ensuring the stable operation of the unit. Referring to the pin system diagram of the unit, the relative dead point and absolute dead point of the unit are designed at the rear bearing box. A thrust support bearing is arranged in the rear bearing box, which is the relative dead point of the unit's expansion; the rear bearing box is fixed to the foundation by anchor bolts, which is the absolute dead point of the expansion of the entire unit. During operation, the unit expands from the rear bearing box to the adjustment end, and transmits the expansion to the cylinder through the cat's claw and positioning key structure. This arrangement can realize the synchronous axial movement between the bearing box and the cylinder in various operating conditions such as start-up and shutdown. At the same time, the relative dead point and the absolute dead point are both set at the rear bearing box, which can minimize the relative expansion difference of the unit and improve the safety of the unit. The arrangement of the relative dead point and the absolute dead point can realize the synchronous axial movement between the bearing box and the cylinder through the pin system, reduce the relative expansion difference between the dynamic and static, and improve the safety and stability of the unit.

Claims

1. A 50MW supercritical CO2 axial flow turbine with volute intake, comprising: The front bearing box, the rear bearing box, the high-pressure cylinder and the rotor are characterized in that: the high-pressure cylinder is a double-layer cylinder structure, including a high-pressure inner cylinder and a high-pressure outer cylinder, the two sides of the high-pressure outer cylinder are connected to the bearing box through positioning cat claws, and the air inlet of the high-pressure cylinder is connected to the main steam regulating combined valve; The blades on the rotor adopt a multi-stage small enthalpy drop reaction structure.

2. A 50MW supercritical CO2 axial flow turbine with volute intake according to claim 1, characterized in that: The rear bearing box is provided with a thrust support bearing, which is the relative dead point of expansion of the unit. The rear bearing box is fixed to the foundation through anchor bolts, which is the absolute dead point of expansion of the entire unit.

3. A 50MW supercritical CO2 axial flow turbine with volute intake according to claim 1, characterized in that: A heat insulation board is fixed between the high-pressure inner cylinder and the dry gas seal to form a heat insulation cavity structure.

4. A 50MW supercritical CO2 axial flow turbine with volute intake according to claim 1, characterized in that: The stationary blades and moving blades of the rotor adopt a pre-twisted assembly structure.

5. A 50MW supercritical CO2 axial flow turbine with volute intake according to claim 1, characterized in that: The positioning cat claw comprises a cat claw, and a positioning key groove is provided on the cat claw. The positioning key groove is clearance-matched with the positioning key installed on the corresponding side bearing box.

6. A 50MW supercritical CO2 axial flow turbine with volute intake according to claim 1, characterized in that: The high-pressure outer cylinder adopts a cylindrical structure, has no center dividing surface, and is vertically divided into three sections.

7. A 50MW supercritical CO2 axial flow turbine with volute intake according to claim 1, characterized in that: The high-pressure inner cylinder adopts a barrel-shaped inner cylinder and a red sleeve ring sealing structure.

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