High-speed double-cantilever axial-flow type low-temperature turbo expander

Abstract

The utility model relates to the technical field of LNG (liquefied natural gas) cold energy power generation, and particularly discloses a high-speed double-cantilever axial-flow type low-temperature turbine expander which comprises a gear box, a connecting pipeline, a high-pressure vortex end and a low-pressure vortex end, the high-pressure vortex end is fixedly connected with the gear box and located at one end of the gear box, and the low-pressure vortex end is fixedly connected with the gear box and located at one end of the gear box. The two ends of the connecting pipeline are connected with the corresponding high-pressure vortex end flange and the corresponding low-pressure vortex end flange respectively. The stability of a rotor system is effectively improved, pneumatic axial thrust generated by the turbines on the two sides can be counteracted, and therefore loss of thrust bearings is reduced, exhaust loss is reduced, sealing pressure is reduced, and sealing reliability is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of LNG cold energy power generation, in particular to a high-speed double-cantilever axial flow type low-temperature turbine expander. Background Art

[0002] At present, the utilization of LNG cold energy mainly relies on the temperature and pressure difference between LNG and the surrounding environment. When high-pressure and low-temperature LNG is converted into natural gas at normal pressure and temperature, the energy stored in LNG is recovered. Among them, LNG cold energy power generation is an important form of efficient utilization of LNG cold energy, and the turbine expander is the key equipment of the LNG cold energy power generation system.

[0003] However, in the prior art, turbine expanders are usually suitable for large flow, high power and high temperature conditions, and are less suitable for LNG cold energy utilization conditions. Utility Model Content

[0004] The purpose of the utility model is to provide a high-speed double-cantilever axial-flow cryogenic turbine expander, aiming to solve the technical problem that the turbine expander in the prior art is usually suitable for large flow, high power and high temperature conditions, but has poor applicability when facing LNG cold energy utilization conditions.

[0005] To achieve the above-mentioned purpose, the utility model adopts a high-speed double-cantilever axial flow low-temperature turbine expander, including a gear box, a connecting pipe, a high-pressure vortex end and a low-pressure vortex end, the high-pressure vortex end is fixedly connected to the gear box and is located at one end of the gear box, the low-pressure vortex end is fixedly connected to the gear box and is located at one end of the gear box, and the two ends of the connecting pipe are respectively connected to the corresponding high-pressure vortex end and the low-pressure vortex end flange.

[0006] Among them, the high-pressure vortex end includes a high-pressure side seal, a high-pressure sealing seat, a high-pressure nozzle ring seat, a high-pressure nozzle ring, a high-pressure stage turbine, a high-pressure inner casing and a high-pressure outer casing, the high-pressure stage turbine is arranged at one end of the gear box, the high-pressure sealing seat is fixedly connected to the gear box and embedded in one end of the gear box, the high-pressure side sealing sleeve is arranged at one end of the gear box, and the high-pressure side seal is embedded in the inside of the high-pressure sealing seat, the high-pressure nozzle ring seat is fixedly connected to the high-pressure sealing seat and is located at one end of the high-pressure sealing seat, the high-pressure outer casing is fixedly connected to the high-pressure sealing seat and is located at one end of the high-pressure sealing seat, the high-pressure nozzle ring is embedded in the inner side of the high-pressure nozzle ring seat, and the high-pressure inner casing is arranged between the high-pressure nozzle ring seat and the high-pressure outer casing.

[0007] Wherein, the low-pressure vortex end includes a low-pressure side seal, a low-pressure seal seat, a thermal insulation cover, a low-pressure nozzle ring seat, a low-pressure nozzle ring, a low-pressure stage turbine, a low-pressure inner casing and a low-pressure outer casing, the low-pressure stage turbine is arranged at one end of the gear box, the low-pressure seal seat is fixedly connected to the gear box and embedded in one end of the gear box, the low-pressure side seal sleeve is arranged on the outer wall of the gear box, and the low-pressure side seal is embedded in the interior of the low-pressure seal seat, the low-pressure nozzle ring seat is fixedly connected to the low-pressure seal seat and is located at one end of the low-pressure seal seat, the low-pressure outer casing is fixedly connected to the low-pressure seal seat and is located at 4 ends of the low-pressure seal seat, the low-pressure nozzle ring is embedded in the interior of the low-pressure nozzle ring seat, the low-pressure inner casing is arranged between the low-pressure nozzle ring seat and the low-pressure outer casing, and the thermal insulation cover is embedded between the low-pressure seal seat and the low-pressure nozzle ring seat.

[0008] The beneficial effects of the high-speed double-cantilever axial-flow low-temperature turbine expander of the utility model are as follows: a double-cantilever structure is adopted to suspend multi-stage turbines, which is suitable for more working conditions and effectively improves the stability of the rotor system. The aerodynamic axial thrusts generated by the turbines on both sides can offset each other, thereby reducing thrust bearing losses. A radial air intake and axial exhaust structure is adopted so that the expanded low-temperature gas is always located in the inner cavity and away from the shell, thereby avoiding low-temperature freezing on the shell surface. The airflow enters the turbine stage flow channel from the inlet flow channel. After doing work in the turbine, the gas does not turn to enter the exhaust flow channel, but is evenly exhausted along the axial direction, thereby reducing exhaust losses, reducing sealing pressure, and improving sealing reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0010] Figure 1 The utility model is a structural schematic diagram of a high-speed double-cantilever axial flow type low-temperature turbine expander.

[0011] Figure 2 The utility model is a cross-sectional view of the internal structure of a high-speed double-cantilever axial-flow low-temperature turbine expander.

[0012] Figure 3 The utility model is a schematic diagram of the airflow direction structure of a high-speed double-cantilever axial flow type low-temperature turbine expander.

[0013] 1-gearbox, 2-connecting pipe, 3-high-pressure turbine end, 4-low-pressure turbine end, 5-high-pressure side seal, 6-high-pressure seal seat, 7-high-pressure nozzle ring seat, 8-high-pressure nozzle ring, 9-high-pressure stage turbine, 10-high-pressure inner casing, 11-high-pressure outer casing, 12-low-pressure side seal, 13-low-pressure seal seat, 14-insulation cover, 15-low-pressure nozzle ring seat, 16-low-pressure nozzle ring, 17-low-pressure stage turbine, 18-low-pressure inner casing, 19-low-pressure outer casing. DETAILED DESCRIPTION

[0014] See also Figures 1 to 3 The utility model provides a high-speed double-cantilever axial-flow cryogenic turbine expander, comprising a gear box 1, a connecting pipe 2, a high-pressure vortex end 3 and a low-pressure vortex end 4, wherein the high-pressure vortex end 3 is fixedly connected to the gear box 1 and is located at one end of the gear box 1, and the low-pressure vortex end 4 is fixedly connected to the gear box 1 and is located at one end of the gear box 1, and the two ends of the connecting pipe 2 are flange-connected to the corresponding high-pressure vortex end 3 and the low-pressure vortex end 4 respectively.

[0015] Further, the high-pressure vortex end 3 includes a high-pressure side seal 5, a high-pressure sealing seat 6, a high-pressure nozzle ring seat 7, a high-pressure nozzle ring 8, a high-pressure stage turbine 9, a high-pressure inner casing 10 and a high-pressure outer casing 11, the high-pressure stage turbine 9 is arranged at one end of the gear box 1, the high-pressure sealing seat 6 is fixedly connected to the gear box 1 and embedded in one end of the gear box 1, the high-pressure side seal 5 is sleeved on one end of the gear box 1, and the high-pressure side seal 5 is embedded in the inside of the high-pressure sealing seat 6, the high-pressure nozzle ring seat 7 is fixedly connected to the high-pressure sealing seat 6 and is located at one end of the high-pressure sealing seat 6, the high-pressure outer casing 11 is fixedly connected to the high-pressure sealing seat 6 and is located at one end of the high-pressure sealing seat 6, the high-pressure nozzle ring 8 is embedded in the inner side of the high-pressure nozzle ring seat 7, and the high-pressure inner casing 10 is arranged between the high-pressure nozzle ring seat 7 and the high-pressure outer casing 11.

[0016] Further, the low-pressure turbine end 4 includes a low-pressure side seal 12, a low-pressure seal seat 13, a heat preservation cover 14, a low-pressure nozzle ring seat 15, a low-pressure nozzle ring 16, a low-pressure stage turbine 17, a low-pressure inner casing 18 and a low-pressure outer casing 19, the low-pressure stage turbine 17 is arranged at one end of the gear box 1, the low-pressure seal seat 13 is fixedly connected to the gear box 1 and embedded in one end of the gear box 1, the low-pressure side seal 12 is sleeved on the outer wall of the gear box 1, and the low-pressure side seal 12 is embedded in the low-pressure seal seat 13. The low-pressure nozzle ring seat 15 is fixedly connected to the low-pressure sealing seat 13 and is located at one end of the low-pressure sealing seat 13. The low-pressure outer shell 19 is fixedly connected to the low-pressure sealing seat 13 and is located at one end of the low-pressure sealing seat 13. The low-pressure nozzle ring 16 is embedded in the low-pressure nozzle ring seat 15. The low-pressure inner shell 18 is arranged between the low-pressure nozzle ring seat 15 and the low-pressure outer shell 19. The thermal insulation cover 14 is embedded between the low-pressure sealing seat 13 and the low-pressure nozzle ring seat 15.

[0017] In this embodiment, a double cantilever structure is adopted to suspend a multi-stage turbine, which is suitable for more working conditions and effectively improves the stability of the rotor system. The aerodynamic axial thrusts generated by the turbines on both sides can offset each other, thereby reducing the thrust bearing loss. A radial air intake and axial exhaust structure is adopted, so that the expanded low-temperature gas is always located in the inner cavity and away from the shell, thereby avoiding low-temperature freezing on the shell surface. The airflow enters the turbine stage flow channel from the intake flow channel. After doing work in the turbine, the gas does not turn to enter the exhaust flow channel, but is evenly exhausted along the axial direction, thereby reducing exhaust loss, reducing sealing pressure, and improving sealing reliability.

[0018] A high-pressure side balance cavity is formed between the high-pressure side seal 5 and the high-pressure nozzle ring seat 7, and is communicated with the exhaust port of the low-pressure vortex end 4, thereby reducing the pressure of the high-pressure side seal 5;

[0019] The inner wall and outer wall of the low-pressure outer shell 19 and the low-pressure sealing seat 13 enclose the low-pressure vortex end 4 inlet flow channel, and the inner cavity of the low-pressure inner shell 18 forms the low-pressure vortex end 4 exhaust flow channel;

[0020] A heat-insulating cavity is formed between the heat-insulating cover 14 and the low-pressure sealing seat 13 to prevent low temperature from affecting the sealing performance;

[0021] A low-pressure side balance air cavity is formed between the low-pressure side seal 12 and the low-pressure nozzle ring seat 15, and is communicated with the exhaust port of the low-pressure turbine end 4, thereby reducing the pressure of the low-pressure side seal 12;

[0022] The high-pressure stage turbine 9 and the low-pressure stage turbine 17 are both axial-flow turbines, and the number of turbine stages can be adjusted to balance the aerodynamic thrust of the turbines at both ends;

[0023] The turbine stage flow passages of the high-pressure stage turbine 9 and the low-pressure stage turbine 17 are full-circle air intake flow passages, which can make the airflow evenly distributed along the circumference of the corresponding low-pressure nozzle ring 16, the high-pressure nozzle ring 8, the high-pressure stage turbine 9 and the low-pressure stage turbine 17, without additional separation loss and secondary flow loss;

[0024] The high-pressure stage turbine 9 and the low-pressure stage turbine 17 are end-face meshed with the main shaft, and torque is transmitted through the end-face teeth.

[0025] The above disclosure is only a preferred embodiment of the present invention, and certainly cannot be used to limit the scope of rights of the present invention. Ordinary technicians in this field can understand that all or part of the processes of the above embodiment and equivalent changes made according to the claims of the present invention still fall within the scope covered by the utility model.

Claims

1. A high-speed double-cantilever axial-flow cryogenic turbine expander, characterized in that: It includes a gearbox, a connecting pipe, a high-pressure vortex end and a low-pressure vortex end, the high-pressure vortex end is fixedly connected to the gearbox and is located at one end of the gearbox, the low-pressure vortex end is fixedly connected to the gearbox and is located at one end of the gearbox, and the two ends of the connecting pipe are respectively connected to the corresponding high-pressure vortex end and the low-pressure vortex end flange; the high-pressure vortex end includes a high-pressure side seal, a high-pressure sealing seat, a high-pressure nozzle ring seat, a high-pressure nozzle ring, a high-pressure stage turbine, a high-pressure inner shell and a high-pressure outer shell, the high-pressure stage turbine is arranged at one end of the gearbox, the high-pressure sealing seat is fixedly connected to the gearbox and embedded in one end of the gearbox, the high-pressure side sealing sleeve is arranged at one end of the gearbox, and the high-pressure side seal is embedded in the inside of the high-pressure sealing seat, the high-pressure nozzle ring seat is fixedly connected to the high-pressure sealing seat and is located at one end of the high-pressure sealing seat, the high-pressure outer shell is fixedly connected to the high-pressure sealing seat and is located at one end of the high-pressure sealing seat, and the high-pressure nozzle ring is embedded in the The inner side of the high-pressure nozzle ring seat, the high-pressure inner shell is arranged between the high-pressure nozzle ring seat and the high-pressure outer shell; the low-pressure vortex end includes a low-pressure side seal, a low-pressure seal seat, a heat preservation cover, a low-pressure nozzle ring seat, a low-pressure nozzle ring, a low-pressure stage turbine, a low-pressure inner shell and a low-pressure outer shell, the low-pressure stage turbine is arranged at one end of the gear box, the low-pressure seal seat is fixedly connected to the gear box and embedded in one end of the gear box, the low-pressure side sealing sleeve is arranged on the outer wall of the gear box, and the The low-pressure side seal is embedded in the interior of the low-pressure sealing seat, the low-pressure nozzle ring seat is fixedly connected to the low-pressure sealing seat and is located at one end of the low-pressure sealing seat, the low-pressure outer shell is fixedly connected to the low-pressure sealing seat and is located at one end of the low-pressure sealing seat, the low-pressure nozzle ring is embedded in the interior of the low-pressure nozzle ring seat, the low-pressure inner shell is arranged between the low-pressure nozzle ring seat and the low-pressure outer shell, and the thermal insulation cover is embedded between the low-pressure sealing seat and the low-pressure nozzle ring seat.

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