Sectional type hollow rotor of high-power supercritical carbon dioxide turbine

Abstract

The utility model relates to the technical field of supercritical carbon dioxide power generation, in particular to a sectional type hollow rotor of a high-power supercritical carbon dioxide turbine, which comprises a first connecting shaft, a first fixing piece, a second connecting shaft, a second fixing piece, an intermediate shaft, a pre-tightening piece, a third connecting shaft and a coupler. The intermediate shaft is in direct contact with a medium, and cooling gas is introduced between the comb seal and the dry gas seal to cool the main shaft; the highest temperature of the second connecting shaft and the third connecting shaft is lower than 200 DEG C, and the highest temperature of the first connecting shaft is lower than 100 DEG C, so that when materials are selected, only the intermediate shaft needs to be made of a high-temperature-resistant alloy material, and the use of high-temperature alloy is reduced; the material use cost is greatly reduced, and the problem that an existing critical carbon dioxide turbine rotor is high in production cost is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of supercritical carbon dioxide power generation, in particular to a segmented hollow rotor of a high-power supercritical carbon dioxide turbine. Background Art

[0002] The circulating power generation system using supercritical carbon dioxide as the medium is highly efficient and can replace the traditional power generation circulation system. In addition, the system is small in size and greatly reduces the equipment manufacturing cost compared to traditional steam power generation.

[0003] With the continuous advancement of supercritical carbon dioxide power generation technology, the installed power of power generation is gradually increasing. For the sake of system efficiency, the temperature of the thermal cycle of supercritical carbon dioxide power generation is relatively high, above 550°C. The main shaft used in the turbine needs to be made of high-temperature alloy steel. High-temperature alloy steel is expensive, which increases the production cost of supercritical carbon dioxide turbine rotors. Summary of the Invention

[0004] The purpose of the utility model is to provide a segmented hollow rotor for a high-power supercritical carbon dioxide turbine, aiming to solve the problem of high production cost of existing supercritical carbon dioxide turbine rotors.

[0005] To achieve the above-mentioned object, the utility model provides a segmented hollow rotor for a high-power supercritical carbon dioxide turbine, comprising a first connecting shaft, a first fixing member, a second connecting shaft, a second fixing member, an intermediate shaft, a pre-tightening member, a third connecting shaft and a coupling;

[0006] The first fixing member is fixedly connected to the first connecting shaft and is located on one side of the first connecting shaft. The second connecting shaft is fixedly connected to the first fixing member and is located on one side of the first fixing member. The second fixing member is fixedly connected to the first fixing member and is located on one side of the first fixing member. The intermediate shaft is fixedly connected to the second fixing member and is located on one side of the intermediate shaft. The pre-tightening member is arranged on one side of the intermediate shaft. The third connecting shaft is arranged on one side of the pre-tightening member. The coupling is arranged on one side of the third connecting shaft.

[0007] Wherein, the first connecting shaft includes a thrust step and a speed measuring gear, the thrust step is fixedly connected to the first fixing member and is located on one side of the first fixing member, and the speed measuring gear is fixedly connected to the thrust step and is located on one side of the thrust step.

[0008] The second connecting shaft includes a shaft body and a first bearing. The shaft body is fixedly connected to the first fixing member and is located on one side of the first fixing member. The first bearing is fixedly connected to the shaft body and is located on the outer side wall of the shaft body.

[0009] The pre-tightening member includes a pull rod and a locking member. The pull rod is fixedly connected to the intermediate shaft and the third connecting shaft. The locking member is fixedly connected to the pull rod and the coupling.

[0010] Wherein, the pre-tightening member further includes a sealing ring, and the sealing ring is arranged between the pull rod and the third connecting shaft.

[0011] The utility model discloses a segmented hollow rotor for a high-power supercritical carbon dioxide turbine. The intermediate shaft has a comb seal and a dry gas seal. The intermediate shaft is in direct contact with the medium, and cooling gas is passed between the comb seal and the dry gas seal to cool the main shaft. Therefore, the intermediate shaft has a relatively high temperature. The maximum temperature of the second and third connecting shafts is less than 200°C, and the maximum temperature of the first connecting shaft is less than 100°C. Therefore, when selecting materials, only the intermediate shaft needs to be made of a high-temperature resistant alloy, reducing the use of high-temperature alloys and significantly reducing material costs. The medium works on the main shaft blades, driving the intermediate shaft and the third connecting shaft to rotate. Torsional force can be transmitted through the coupling. Driving the intermediate shaft and the third connecting shaft requires transmitting high-power torsional force, rotor weight, and axial force, requiring a high yield strength of the material in this segment. The first and second connecting shafts only bear torque due to bearing power loss, rotor weight, and axial force. Therefore, the first and second connecting shafts can be made of materials with lower yield strength, further reducing material costs and addressing the high production cost of existing supercritical carbon dioxide turbine rotors. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art.

[0013] Figure 1 The utility model is a structural schematic diagram of a segmented hollow rotor of a high-power supercritical carbon dioxide turbine.

[0014] Figure 2 The utility model is a cross-sectional view of a segmented hollow rotor of a high-power supercritical carbon dioxide turbine.

[0015] 101-first connecting shaft, 102-first fixing part, 103-second connecting shaft, 104-second fixing part, 105-intermediate shaft, 106-preload part, 107-third connecting shaft, 108-coupling, 109-thrust step, 110-speed measuring gear, 112-shaft body, 113-first bearing, 114-pull rod, 115-locking part, 116-sealing ring. DETAILED DESCRIPTION

[0016] See also Figure 1-Figure 2 , Figure 1 This is a structural diagram of a segmented hollow rotor of a high-power supercritical carbon dioxide turbine. Figure 2 The utility model is a cross-sectional view of a segmented hollow rotor of a high-power supercritical carbon dioxide turbine. The utility model provides a segmented hollow rotor of a high-power supercritical carbon dioxide turbine, comprising a first connecting shaft 101, a first fixing member 102, a second connecting shaft 103, a second fixing member 104, an intermediate shaft 105, a pre-tightening member 106, a third connecting shaft 107 and a coupling 108. The first connecting shaft 101 comprises a thrust step 109 and a speed measuring gear 110. The second connecting shaft 103 comprises a shaft body 112 and a first bearing 113. The pre-tightening member 106 comprises a pull rod 114, a locking member 115 and a sealing ring 116.

[0017] According to this specific embodiment, the first fixing member 102 is fixedly connected to the first connecting shaft 101 and is located on one side of the first connecting shaft 101. The second connecting shaft 103 is fixedly connected to the first fixing member 102 and is located on one side of the first fixing member 102. The second fixing member 104 is fixedly connected to the first fixing member 102 and is located on one side of the first fixing member 102. The intermediate shaft 105 is fixedly connected to the second fixing member 104 and is located on one side of the intermediate shaft 105. The pre-tightening member 106 is provided on one side of the intermediate shaft 105. The third connecting shaft 107 is provided on one side of the pre-tightening member 106. The coupling 108 is provided on one side of the third connecting shaft 107. The first connecting shaft 101 provides installation conditions for the first fixing member 102. The first connecting shaft 101 can be used for rotor measurement. In order to increase the speed and withstand the thrust, the turbine rotor blades are often designed into multiple stages. In this way, the span and weight of the rotor will be greatly increased, which will lead to a decrease in the stiffness of the entire rotor, and it is easy for the critical speed of the rotor to approach the operating speed, posing a serious threat to the normal operation of the unit. The first fixing member 102 can connect the first connecting shaft 101 and the second connecting shaft 103. The middle is hollow, which reduces the weight of the rotor and thus reduces the possibility of a decrease in the stiffness of the entire rotor. The second fixing member 104 can connect the second connecting shaft 103 and the intermediate shaft 105. The intermediate shaft 105 is in direct contact with the medium and can pass cooling air to cool the main shaft. The pre-tightening member 106 provides installation conditions for the third connecting shaft 107 and the coupling 108. The rotation of the third connecting shaft 107 can drive the shaft connected to the coupling 108 to rotate.

[0018] Among them, the thrust step 109 is fixedly connected to the first fixing member 102 and is located on one side of the first fixing member 102. The speed measuring gear 110 is fixedly connected to the thrust step 109 and is located on one side of the thrust step 109. The thrust step 109 is used to bear the thrust of the rotor, and the speed measuring gear 110 is used to measure the rotor speed.

[0019] Secondly, the shaft body 112 is fixedly connected to the first fixing part 102 and is located on one side of the first fixing part 102. The first bearing 113 is fixedly connected to the shaft body 112 and is located on the outer wall of the shaft body 112. The shaft body 112 provides installation conditions for the first fixing part 102. The shaft body 112 is made of hollow material and has a dry gas seal. The first bearing 113 can reduce the friction coefficient during its movement.

[0020] At the same time, the pull rod 114 is fixedly connected to the intermediate shaft 105 and to the third connecting shaft 107. The locking piece 115 is fixedly connected to the pull rod 114 and to the coupling 108. The pull rod 114 provides installation conditions for the third connecting shaft 107. The stability of the third connecting shaft 107 can be improved by the locking piece 115.

[0021] In addition, the sealing ring 116 is provided between the pull rod 114 and the third connecting shaft 107 , and the sealing ring 116 can increase the friction between the pull rod 114 and the intermediate shaft 105 .

[0022] The intermediate shaft 105 has nine stages of blades, a comb seal and a dry gas seal. The first fixing member 102 and the second fixing member 104 are both bolts and nuts. The locking member 115 is a locking nut. The intermediate shaft 105 is in direct contact with the medium. Cooling air is passed between the comb seal and the dry gas seal to cool the main shaft. Therefore, the temperature of the intermediate shaft 105 is relatively high. The maximum temperature of the second connecting shaft 103 and the third connecting shaft 107 is less than 200°C, and the maximum temperature of the first connecting shaft 101 is less than 100°C. Therefore, when selecting materials, only the intermediate shaft 105 needs to be made of high-temperature resistant alloy material, which reduces the use of high-temperature alloys and greatly reduces material usage costs. The medium works on the main shaft blades, driving the intermediate shaft 105 and the third connecting shaft 107 to rotate. The torsional force can be transmitted through the coupling 108. Driving the intermediate shaft 105 and the third connecting shaft 107 requires transmitting a relatively large power torsional force, the weight of the rotor portion, and the axial force, requiring the yield strength of this section of material to be relatively high; while the first connecting shaft 101 and the second connecting shaft 103 only bear the torque of the bearing power loss, the weight of the rotor portion, and the axial force. Therefore, the first connecting shaft 101 and the second connecting shaft 103 can be made of a material with a lower yield strength, further reducing the material usage cost and solving the problem of high production cost of existing critical carbon dioxide turbine rotors.

[0023] The above disclosure is merely one or more preferred embodiments of the present application and is not intended to limit the scope of the present application. A person skilled in the art will understand that all or part of the processes of the above embodiments and equivalent changes made in accordance with the claims of the present application are still within the scope of the present application.

Claims

1. A segmented hollow rotor for a high-power supercritical carbon dioxide turbine, characterized in that: It includes a first connecting shaft, a first fixing member, a second connecting shaft, a second fixing member, an intermediate shaft, a pre-tightening member, a third connecting shaft and a coupling; The first fixing member is fixedly connected to the first connecting shaft and is located on one side of the first connecting shaft. The second connecting shaft is fixedly connected to the first fixing member and is located on one side of the first fixing member. The second fixing member is fixedly connected to the first fixing member and is located on one side of the first fixing member. The intermediate shaft is fixedly connected to the second fixing member and is located on one side of the intermediate shaft. The pre-tightening member is arranged on one side of the intermediate shaft. The third connecting shaft is arranged on one side of the pre-tightening member. The coupling is arranged on one side of the third connecting shaft.

2. A segmented hollow rotor for a high-power supercritical carbon dioxide turbine according to claim 1, characterized in that: The first connecting shaft includes a thrust step and a speed measuring gear. The thrust step is fixedly connected to the first fixing member and is located on one side of the first fixing member. The speed measuring gear is fixedly connected to the thrust step and is located on one side of the thrust step.

3. The segmented hollow rotor of a high-power supercritical carbon dioxide turbine according to claim 1, characterized in that: The second connecting shaft includes a shaft body and a first bearing. The shaft body is fixedly connected to the first fixing member and is located on one side of the first fixing member. The first bearing is fixedly connected to the shaft body and is located on the outer side wall of the shaft body.

4. The segmented hollow rotor of a high-power supercritical carbon dioxide turbine according to claim 1, characterized in that: The pre-tightening member includes a pull rod and a locking member. The pull rod is fixedly connected to the intermediate shaft and the third connecting shaft. The locking member is fixedly connected to the pull rod and the coupling.

5. The segmented hollow rotor of a high-power supercritical carbon dioxide turbine according to claim 4, characterized in that: The pre-tightening member further includes a sealing ring, which is arranged between the pull rod and the third connecting shaft.

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