CN210829404U

CN210829404U - Supercritical carbon dioxide turbine disk, main shaft and nozzle ring mounting structure

Info

Publication number: CN210829404U
Application number: CN201921998270.0U
Authority: CN
Inventors: 李扬; 周东; 邓浩; 但光局; 文鑫; 王亚
Original assignee: Chongqing Jiangjin Shipbuilding Industry Co Ltd
Current assignee: Chongqing Jiangjin Shipbuilding Industry Co Ltd
Priority date: 2019-11-19
Filing date: 2019-11-19
Publication date: 2020-06-23
Anticipated expiration: 2029-11-19

Abstract

The utility model discloses a supercritical carbon dioxide turbine dish, main shaft and nozzle ring mounting structure, including main shaft and multistage turbine dish and multistage nozzle ring, interior casing and shell body pass through bolt-up connection, be equipped with the connecting axle between main shaft and the turbine dish, the connecting axle passes through connecting bolt fixed connection with the main shaft and through main shaft shoulder axial spacing, the connecting axle is close to one end of multistage turbine dish and passes through fastener fastening connection with multistage turbine dish, multistage turbine dish passes through connecting axle b terminal surface axial spacing, multistage nozzle ring and multistage turbine dish arrange along axial alternate arrangement, install through cylindric lock circumference location between the adjacent two-stage nozzle ring, multistage nozzle ring is connected by the close fit of pin, through interior casing second shaft shoulder axial spacing, multistage nozzle ring's last nozzle ring and interior casing pass through internal thread cylindric lock circumference location installation, fastened to the inner housing by screws.

Description

Supercritical carbon dioxide turbine disk, main shaft and nozzle ring mounting structure

Technical Field

The utility model belongs to the technical field of the turbine, concretely relates to supercritical carbon dioxide turbine wheel dish, main shaft and nozzle cascade mounting structure.

Background

The turbine utilizes the expansion of working medium when flowing through the nozzle ring and the turbine disc to convert thermodynamic energy into gas kinetic energy to push the turbine disc to rotate, and the turbine disc is connected with the main shaft to drive the load at the tail end of the transmission shaft to do work. Wherein the connection structure of the turbine disk and the main shaft is an important factor affecting power transmission. The high-power unit mostly adopts an arrangement form that a turbine disc is positioned in the middle of a main shaft, the turbine disc and the main shaft are integrated or sleeved in a hot mode, the medium-and-small-power unit mostly adopts a cantilever arrangement, and the turbine disc is positioned at one end of the main shaft and connected with the main shaft through a bolt.

The supercritical carbon dioxide has high density compared with other media, and the diameter of a turbine disc of the supercritical carbon dioxide turbine is small under the same power; in order to improve the pneumatic efficiency, the rotating speed of the main shaft is higher, usually reaches 24000rpm and above, and the shaft neck of the main shaft is smaller due to the limitation of the linear speed of the bearing, and the diameter of the shaft neck is usually 50mm or less; in order to ensure reliable power transmission from the turbine disk to the main shaft, on one hand, the turbine disk is usually pressed on the main shaft by a plurality of bolts, but the arrangement of the plurality of bolts on the end face of the main shaft with the small diameter of the supercritical carbon dioxide turbine has great difficulty. On the other hand, when the turbine adopts a multistage scheme, because the nozzle ring and the turbine disk are alternately arranged, the static blade ring needs to be radially split into two halves, which brings difficulty to the processing and installation of the small-diameter supercritical carbon dioxide nozzle ring.

Disclosure of Invention

An object of the utility model is to overcome prior art not enough, provide a supercritical carbon dioxide turbine wheel dish, main shaft and nozzle cascade mounting structure, can realize the reliable connection of turbine dish with the main shaft, guarantee that power transmission is stable to can guarantee the processing and the installation accuracy of nozzle cascade.

The purpose of the utility model is realized like this:

a supercritical carbon dioxide turbine disk, main shaft and nozzle ring mounting structure comprises a main shaft arranged in a turbine outer shell, a multistage turbine disk and a multistage nozzle ring which are arranged in the turbine inner shell, wherein the inner shell and the outer shell are fixedly connected through bolts, a connecting shaft is also arranged between the main shaft and the turbine disk, the end a of the connecting shaft is fixedly connected with the main shaft through a connecting bolt and axially limited through a main shaft shoulder, the end b of the connecting shaft is fixedly connected with the multistage turbine disk through a fastener, the multistage turbine disk is axially limited through the end face of the end b of the connecting shaft, the multistage nozzle ring and the multistage turbine disk are axially and alternately arranged, the adjacent two stages of nozzle rings are circumferentially positioned and mounted through cylindrical pins, the multistage nozzle ring is tightly matched and connected through pins, the second step face of the inner shell is axially limited, and the last stage of the multistage nozzle ring and the inner, fastened to the inner housing by screws.

Furthermore, the main shaft is provided with an extending end which is a cam-shaped shaft, a first threaded hole is axially formed in the center of the extending end of the main shaft, a cam-shaped hole is axially formed in the end of the connecting shaft a and matched with the cam-shaped shaft of the extending end of the main shaft, a second threaded through hole is axially formed in the center of the connecting shaft, third threaded holes are circumferentially and uniformly formed in the end of the connecting shaft b and used for being in threaded connection with a fastener to tightly press the multistage turbine disc on the connecting shaft, the first threaded hole and the second threaded through hole are in threaded connection with the connecting bolt, the major diameter of the first threaded hole is smaller than the minor diameter of the second threaded through hole, and the second threaded hole isThread pitch P of a threaded hole₁Thread pitch P of second threaded through hole₂. The cam profile is connected with the torque transmission device, so that the torque transmission device is simple, stable and efficient, the connecting shaft can only move but cannot rotate relative to the main shaft during fastening connection, radial space is saved for arrangement of a third threaded hole in the connecting shaft, and fastening reliability of the turbine disc and a fastening piece of the connecting shaft is guaranteed.

Furthermore, the connecting bolt is provided with a small-diameter section thread and a large-diameter section thread, the small-diameter section thread is matched with a first threaded hole of the main shaft, the large-diameter section thread is matched with a second threaded through hole of the connecting shaft, the connecting shaft is tightly pressed on the main shaft by screwing the connecting bolt, and the tooth pitch of the small-diameter section thread and the tooth pitch of the large-diameter section thread are respectively the same as that of the corresponding first threaded hole and second threaded through hole. The connecting bolt with special design saves the radial space of the connecting shaft under the condition of providing required pretightening force, provides sufficient space for the arrangement of the fastening piece of the turbine disc and the connecting shaft on the connecting shaft, and is favorable for improving the fastening reliability of the fastening piece.

Further, multistage turbine dish includes the level four, and first-order turbine dish and connecting axle, second level turbine dish and third level turbine dish, third level turbine dish and fourth level turbine dish all pass through cylinder hole axle clearance fit and turbine dish terminal surface axial positioning, multistage nozzle cascade also includes the level four, and first-order nozzle cascade is located first-order turbine dish front end, and it is spacing through interior casing second step face axial, and adjacent two-stage nozzle cascade arranges with adjacent two-stage turbine dish along axial NULL. Ensuring the coaxiality and the verticality with the axis of the high-speed rotor. The alternate axial installation of level four turbine dish and level four nozzle cascade avoids the radial split of nozzle cascade, is favorable to guaranteeing processing and the installation accuracy of nozzle cascade.

Further, still be equipped with the sealing member between connecting axle and the shell body, the sealing member passes through bolt and shell body fixed connection, it is sealed to be equipped with between the first order nozzle cascade and the connecting axle, and it is sealed to be equipped with the first order movable vane between the first order turbine dish, and it is sealed with the second level movable vane to be equipped with between the second level nozzle cascade and the second level turbine dish respectively, it is sealed with the third level movable vane to be equipped with between the third level nozzle cascade and the third level turbine dish respectively, it is sealed with the fourth level movable vane between the fourth level nozzle cascade and the fourth level turbine dish respectively.

Due to the adoption of the technical scheme, the invention has the following beneficial effects:

1. the connecting shaft is additionally arranged between the turbine main shaft and the turbine disc, the part of the main shaft, which is matched with the connecting shaft, is set to be in a cam type structure, and the cam type structure is used for connecting the torque transmission, so that the structure is simple, stable and efficient, and when the main shaft is tightly connected with the connecting shaft, the cam type structure enables the connecting shaft to only axially move without rotating;

2. the specially designed connecting bolt is adopted to design the small-diameter thread section and the large-diameter thread section and limit the thread pitch P of the small-diameter thread section₁Pitch P of large diameter screw thread section₂The main shaft is provided with a first threaded hole matched with the small-diameter threaded section, the connecting shaft is provided with a second threaded through hole matched with the large-diameter threaded section, and the connecting shaft and the main shaft can be tightly connected only by screwing one connecting bolt at the center of the end surface of the connecting shaft under the condition of providing required pretightening force, so that the radial space of the connecting shaft is saved, sufficient space is provided for the arrangement of a fastening piece of the turbine disc and the connecting shaft on the connecting shaft, and the reliability of the fastening piece is improved;

3. the four-stage turbine disc and the four-stage nozzle ring are alternately and axially installed, adjacent two-stage turbine discs are axially positioned through cylindrical hole shaft clearance fit and the end faces of the turbine discs, the coaxiality and the verticality of the axis of the high-speed rotor shaft are guaranteed, the adjacent two-stage nozzle rings are installed through cylindrical pin circumferential positioning, the four-stage nozzle rings are fixedly connected through pins, the four-stage turbine discs and the four-stage nozzle rings are alternately and axially installed, the radial split of the nozzle rings is avoided, and the processing and installation accuracy of the nozzle rings are guaranteed.

Drawings

FIG. 1 is a schematic view of the installation structure of the present invention;

FIG. 2 is a cross-sectional view A-A of FIG. 1;

FIG. 3 is a schematic view of the seal disposed on the nozzle ring of the present invention;

fig. 4 is a schematic diagram of the form and position tolerance of the turbine disc, the main shaft and the connecting shaft;

fig. 5 is a mounting state diagram of the connecting bolt, the main shaft and the connecting shaft in the present invention.

Reference numerals

In the drawing, 1 is a connecting bolt, 2 is a main shaft, 3 is a connecting shaft, 4 is a sealing part, 5 is an outer shell, 6 is a first-stage nozzle ring, 7 is a first-stage turbine disk, 8 is a second-stage nozzle ring, 9 is a second-stage turbine disk, 10 is a third-stage nozzle ring, 11 is a third-stage turbine disk, 12 is a screw, 13 is a gasket a, 14 is a fourth-stage nozzle ring, 15 is a pin, 16 is a fourth-stage turbine disk, 17 is a screw, 18 is a gasket b, 19 is a nut, 20 is an internal thread cylindrical pin, 21 is an inner shell, 22 is a cylindrical pin, 23 is a high-speed rotor shaft axis,

1-1 small diameter section thread, 1-2 large diameter section thread, 2-1 cam type shaft, 2-2 first threaded hole, 2-3 shaft shoulder, 3-1 cam type hole, 3-2 second threaded through hole, 3-3 connecting shaft a end, 3-4 connecting shaft b end, 3-5 third threaded hole,

6-1 first stage inter-sealing, 6-2 first stage moving blade sealing, 8-1 second stage inter-sealing, 8-2 second stage moving blade sealing, 10-1 third stage inter-sealing, 10-2 third stage moving blade sealing, 14-1 fourth stage inter-sealing, 14-2 fourth stage moving blade sealing, 21-1 inner shell first step surface, 21-2 inner shell second step surface, L_ΔThe distance between the end surface of the connecting shaft a and the shaft shoulder of the main shaft is reserved,

l1 is the length of the small diameter section of the connecting bolt screwed into the first threaded hole,

l2 is the length of the connecting bolt large diameter section screwed into the second threaded hole,

l is the axial moving distance of the connecting bolt,

the position C is a small-diameter section thread screwing position, and the position D is a large-diameter section thread screwing position.

Detailed Description

Embodiments of the present invention will be described in further detail with reference to the accompanying drawings, in which the arrows in fig. 1 indicate the intake and exhaust directions.

Referring to fig. 1-5, a supercritical carbon dioxide turbine disk, spindle and nozzle ring mounting structure comprises a spindle 2 disposed in an outer turbine housing 5, and a multi-stage turbine disk and a multi-stage nozzle ring disposed in an inner turbine housing 21, wherein the inner housing 21 and the outer housing 5 are fastened by bolts, a connecting shaft 3 is further disposed between the spindle 2 and the turbine disk, ends 3-3 of the connecting shaft a and the spindle 2 are fixedly connected by a connecting bolt 1 and axially limited by a spindle shoulder 2-3, ends 3-4 of the connecting shaft b and the multi-stage turbine disk are fastened by a fastener, the multi-stage turbine disk is axially limited by an end face 3-4 of the connecting shaft b, the multi-stage nozzle rings and the multi-stage turbine disks are axially and alternately arranged, and adjacent two stages of nozzle rings are circumferentially positioned and mounted by a cylindrical pin 22, the final nozzle ring of the multistage nozzle ring is circumferentially positioned and installed with the inner shell 21 through an internal threaded cylindrical pin 20 and is fastened to the inner shell 21 through a bolt 12 and a washer a13, and the final nozzle ring and the inner shell 21 are axially limited through a second step surface 21-2 of the inner shell by a pin 15 in a tight fit mode.

In order to ensure the reliable connection between the main shaft 2 and the connecting shaft 3, and to transmit torque simply, smoothly and efficiently, and to make the connecting shaft 3 only move but not rotate when fastened with respect to the main shaft 2, as shown in fig. 1 and 2, in this embodiment, the main shaft 2 has an extended end which is a cam-shaped shaft 2-1, a first threaded hole 2-2 is axially formed at the center of the extended end of the main shaft, a cam-shaped hole 3-1 is axially formed at the end 3-3 of the connecting shaft a, which is engaged with the cam-shaped shaft 2-1 at the extended end of the main shaft, a second threaded through hole 3-2 is axially formed at the center of the connecting shaft, third threaded holes 3-5 are circumferentially and uniformly formed at the end 3-4 of the connecting shaft b, which is used for threaded connection with a fastening member, and the fastening member in this embodiment employs a screw 17, a washer b18, the multistage turbine disc is tightly pressed on the connecting shaft 3, the first threaded hole 2-2 and the second threaded through hole 3-2 are in threaded connection with the connecting bolt 1, the major diameter of the first threaded hole 2-2 is smaller than the minor diameter of the second threaded through hole 3-2, and the thread pitch P of the first threaded hole 2-2₁Thread pitch P of second threaded through hole 3-2₂。

As shown in fig. 1 and 5, wherein a in fig. 5 represents a state in which the connecting bolt 1 starts to be screwed into the main shaft 2 and the connecting shaft 3, B in fig. 5 represents a state after the connecting bolt 1 is screwed into the main shaft 2 and the connecting shaft 3, and B in fig. 5 represents a state after the connecting bolt 1 is screwed into the main shaft, so as to save a radial space of the connecting shaft and provide a sufficient space for arranging a fastening piece of the turbine disc and the connecting shaft on the connecting shaft, in this embodiment, a specially designed connecting bolt is adopted, so as to improve fastening reliability of the connecting bolt in the case of providing a required pre-tightening force, the connecting bolt is of an integral structure and is provided with a small-diameter section thread 1-1 and a large-diameter section thread 1-2, the small-diameter section thread 1-1 is matched with a first threaded hole 2-2 of the main shaft, the large-diameter section thread 1-2 is matched with a second threaded through hole 3-2 of the connecting shaft, the connecting The pitch of the thread is the same as that of the second threaded through hole.

Due to the special design of the connecting bolt 1, when the connecting shaft 3 is connected to the main shaft 2, certain conditions need to be met, and the specific installation process and conditions are as follows:

the cam-shaped hole 3-1 of the connecting shaft 3 is sleeved on the cam-shaped shaft 2-1 of the main shaft 2, and the distance L from the end face 3-3 of the connecting shaft a to the shaft shoulder 2-3 of the main shaft is ensured_ΔTwo sections of threads of the connecting bolt 1 are simultaneously screwed into the first threaded hole 2-2 and the second threaded through hole 3-2, the connecting bolt 1 is a whole, the axial moving distances of all points on the connecting bolt are necessarily the same, and when the connecting bolt 1 is screwed into a certain number of turns (namely the number of threads), the thread pitch P of the threads of the small-diameter section is caused₁Thread pitch P of large diameter section₂The axial distance difference is offset by the axial movement of the connecting shaft 3, the connecting shaft 3 is connected with the cam profile of the main shaft 2, so that the connecting shaft 3 does not rotate when moving axially, when the end face a 3-3 of the connecting shaft 3 is contacted with the shoulder 2-3 of the main shaft 2, the screwing-in process is finished, the connecting bolt 1 is screwed, and then the axial pre-tightening force is generated to tightly press the connecting shaft 3 on the main shaft 2. When the screwing-in is finished, the small diameter section screw thread is screwed into the first threaded hole 2-2 for the length L1, and the number of the screwed-in thread teeth n₁L1 is equal to the axial moving distance L of the connecting bolt 1, the length L2 of the large-diameter section screw thread screwed into the second screw hole 3-2, and the number n of the screwed thread₂The connecting shaft 3 moves axially by a distance L delta, so that the following relational expression can be deduced;

L₁＝n₁×P₁

L₂＝n₂×P₂

L＝L₁

L＝L₂-L_Δ

n₁＝n₂＝n

namely n × (P)₁-P₂)＝L_Δ

The calculation result shows that when the main shaft 2, the connecting shaft 3 and the connecting bolt 1 are installed, the reserved distance L delta needs to satisfy the product of the thread number n and the thread distance difference, if the reserved distance L delta is too large, the connecting shaft 3 cannot be axially installed in place, and if the reserved distance L delta is too small, the connecting bolt 1 cannot be axially installed in place, so that the thread number of stress is reduced, the stress intensity of the threads is reduced, and when the connecting bolt 1 emits too much right end of the connecting shaft, the connecting bolt can interfere with the multistage turbine disc.

As shown in fig. 1 and 4, fig. 4 shows important geometric tolerance requirements of mutual matching of a hole shaft and an end face between a turbine disc, a main shaft and a connecting shaft, wherein i in fig. 4 shows the matching perpendicularity of the main shaft and a shaft shoulder of the connecting shaft, ii shows the coaxiality of the main shaft and a cylindrical hole shaft matching face of the connecting shaft, iii shows the coaxiality of the cylindrical hole shaft matching face of the turbine disc, and iv shows the perpendicularity of the end face matching face of the turbine disc

The multi-stage turbine disc adopted by the turbine in the embodiment comprises four stages, wherein the first-stage turbine disc 7 and the connecting shaft 3, the second-stage turbine disc 9 and the third-stage turbine disc 11, and the third-stage turbine disc 11 and the fourth-stage turbine disc 16 are in clearance fit through cylindrical hole shafts and are axially positioned through the end faces of the turbine discs, so that the coaxiality and the verticality of the cylindrical hole shafts of the two adjacent stages of turbine discs and the end faces of the turbine discs and the axis 23 of the high-speed rotor are ensured; the multistage nozzle ring also comprises four stages, the first-stage nozzle ring 6 is arranged at the front end of the first-stage turbine disc 7 and is axially limited by a second step surface 21-2 of the inner shell, the adjacent two-stage nozzle ring and the adjacent two-stage turbine disc are axially and alternately arranged, when the turbine disc is specifically installed, the corresponding first-stage nozzle ring 6, second-stage nozzle ring 8, third-stage nozzle ring 10, fourth-stage nozzle ring 14 and turbine disc are alternately arranged, the adjacent first-stage nozzle ring 6 and second-stage nozzle ring 8, second-stage nozzle ring 8 and third-stage nozzle ring 10, third-stage nozzle ring 10 and fourth-stage nozzle ring 14 are circumferentially positioned by cylindrical pins 22, the fourth-stage nozzle ring 14 is circumferentially positioned with the inner shell 21 by the cylindrical pins 20 with internal threads, and the connecting surface of the fourth-stage nozzle ring 14 and the third-stage nozzle ring 10 is slightly higher than, through compressing tightly fourth level nozzle ring 14 with screw 12, compress tightly on the second step face 21-2 of inner housing 21 with four level nozzle ring is whole, internal thread cylinder long pin 15 passes four

level nozzle ring

6, 8, 10, 14 to with four level nozzle ring interference fit, prevent that adjacent nozzle ring from taking place to rotate, the radial split of nozzle ring is avoided in the alternative axial installation of four level turbine dish and four level nozzle ring, is favorable to guaranteeing processing and the installation accuracy of nozzle ring.

As shown in fig. 3, in this embodiment, a sealing member 4 is further disposed between the connecting shaft 3 and the outer housing 5, the sealing member 4 is fixedly connected to the outer housing 5 through a bolt, a first inter-stage seal 6-1 is disposed between the first-stage nozzle ring 6 and the connecting shaft 3, and a first-stage movable vane seal 6-2 is arranged between the first-stage turbine disc 7 and the second-stage nozzle ring 8, a second-stage inter-seal 8-1 and a second-stage movable vane seal 8-2 are respectively arranged between the second-stage nozzle ring 8 and the second-stage turbine disc 9, a third-stage inter-seal 10-1 and a third-stage movable vane seal 10-2 are respectively arranged between the third-stage nozzle ring 10 and the third-stage turbine disc 11, a fourth-stage inter-seal 14-1 and a fourth-stage movable vane seal 14-2 are respectively arranged between the fourth-stage nozzle ring 14 and the fourth-stage turbine disc 16, and influence of interstage leakage of working medium in the turbine housing on efficiency is reduced.

The utility model discloses a turbine dish, main shaft and nozzle cascade's mounting structure can realize the reliable connection of turbine dish and main shaft, guarantees the stability of supercritical carbon dioxide turbine power transmission.

Finally, it is noted that the above-mentioned preferred embodiments illustrate rather than limit the invention, and that, although the invention has been described in detail with reference to the above-mentioned preferred embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention as defined by the appended claims.

Claims

1. Supercritical carbon dioxide turbine wheel dish, main shaft and nozzle cascade mounting structure is including setting up the main shaft in the turbine outer casing and setting up multistage turbine wheel dish and multistage nozzle cascade in the turbine inner casing, interior casing and shell body pass through bolt-up connection, its characterized in that: the multi-stage turbine disk is characterized in that a connecting shaft is further arranged between the main shaft and the turbine disk, the a end of the connecting shaft is fixedly connected with the main shaft through a connecting bolt and axially limited through a main shaft shoulder, the b end of the connecting shaft is fixedly connected with the multi-stage turbine disk through a fastener, the multi-stage turbine disk is axially limited through the b end face of the connecting shaft, the multi-stage nozzle rings and the multi-stage turbine disk are axially and alternately arranged, adjacent two-stage nozzle rings are circumferentially positioned and installed through cylindrical pins, the multi-stage nozzle rings are tightly matched and connected through pins and axially limited through a second step face of the inner shell, and the last-stage nozzle ring and the inner shell of the multi.

2. The supercritical carbon dioxide turbine disk, main shaft and nozzle ring mounting structure of claim 1, wherein: the main shaft is provided with an extending end which is a cam-shaped shaft, a first threaded hole is axially formed in the center of the extending end of the main shaft, a cam-shaped hole is axially formed in the end a of the connecting shaft and matched with the cam-shaped shaft of the extending end of the main shaft, a second threaded through hole is axially formed in the center of the connecting shaft, third threaded holes are circumferentially and uniformly formed in the end b of the connecting shaft and used for being in threaded connection with a fastener to tightly press the multi-stage turbine disc on the connecting shaft, the first threaded hole and the second threaded through hole are in threaded connection with the connecting bolt, the major diameter of the first threaded hole is smaller than the minor diameter of the second threaded through hole, and the thread pitch P of the first threaded₁Thread pitch P of second threaded through hole₂。

3. The supercritical carbon dioxide turbine disk, main shaft and nozzle ring mounting structure of claim 2, wherein: the connecting bolt is provided with a small-diameter section thread and a large-diameter section thread, the small-diameter section thread is matched with a first threaded hole of the main shaft, the large-diameter section thread is matched with a second threaded through hole of the connecting shaft, the connecting shaft is tightly pressed on the main shaft by screwing the connecting bolt, and the tooth pitches of the small-diameter section thread and the large-diameter section thread are respectively the same as those of the corresponding first threaded hole and the second threaded through hole.

4. The supercritical carbon dioxide turbine disk, main shaft and nozzle ring mounting structure of claim 1, wherein: multistage turbine dish includes the level four, and first-level turbine dish and connecting axle, second level turbine dish and third level turbine dish, third level turbine dish all pass through cylindrical hole axle clearance fit and turbine dish terminal surface axial positioning with the fourth level turbine dish, multistage nozzle ring also includes the level four, and first-level nozzle ring is located first-level turbine dish front end, and it is spacing through interior casing second step face axial, and adjacent two-stage nozzle ring arranges with adjacent two-stage turbine dish along axial NULL.

5. The supercritical carbon dioxide turbine disk, main shaft and nozzle ring mounting structure of claim 4, wherein: still be equipped with the sealing member between connecting axle and the shell body, the sealing member passes through bolt and shell body fixed connection, it is sealed to be equipped with between the first order nozzle cascade and the connecting axle, and it is sealed to be equipped with the first order movable vane between the first order turbine dish, and it is sealed with the second order movable vane to be equipped with between the second order nozzle cascade and the second order turbine dish respectively, it is sealed with the third order movable vane to be equipped with between the third order nozzle cascade and the third order turbine dish respectively, it is sealed with the fourth order movable vane to be equipped with between the fourth order nozzle cascade and the fourth order turbine dish respectively.