Cryogenic liquid turbine

Abstract

A cryogenic liquid turbine is provided, wherein, impeller end of the rotor and nozzle assembly are received into cavity of volute, and main part of the volute is put into perlite cold box; insulation pad is used between the volute and machine housing to insulate heat; impeller outlet is connected to diffuser pipe. A nozzle assembly is connected to the machine housing by a nozzle compression flange; a nozzle compression plate adjusts a compactness of nozzle vanes by a disc spring; a nozzle turntable is connected on a nozzle chassis, and adjusts the nozzle vane stagger angle by adjusting mechanism passing through the volute; impeller shroud side seal is axially fixed on the nozzle compression flange, and a shaft seal is axially fixed to a seal gas part; the seal gas part and an oil seal are axially fixed to the machine housing by a bolt.

Claims

1. A cryogenic liquid turbine comprising: a rotor, a machine housing, a nozzle assembly, a volute, and a diffuser pipe; wherein, an impeller end of said rotor and said nozzle assembly are positioned in said volute; a perlite cold box surrounds at least said volute to insulate heat; an insulation pad is positioned between said volute and said machine housing to insulate said heat.

2. The cryogenic liquid turbine, as recited in claim 1, wherein said rotor comprises: a shaft, an impeller, and a coupling; wherein, said shaft is rotatably fixed in said machine housing by two thrust journal bearings; two ends of said shaft are in a form of a triangular polygon; one end of said shaft is fitted to said impeller and fixed by an impeller fastening screw; the other end of said shaft is connected to said coupling.

3. The cryogenic liquid turbine, as recited in claim 1, wherein, an impeller outlet is connected to said diffuser pipe, said diffuser pipe configured for reducing outlet flow velocity at said impeller outlet and reducing flow loss.

4. The cryogenic liquid turbine, as recited in claim 1, wherein, said nozzle assembly is connected to said machine housing by a nozzle compression flange, and said nozzle compression flange is axially fixed on an impeller shroud side seal; a seal gas part and an oil seal are axially fixed on said machine housing by a bolt, and a shaft seal is axially fixed on said seal gas part; said diffuser pipe is axially fixed on said volute, in such a manner that said cryogenic liquid turbine is easy to be accurately orientated and installed in an axial direction.

5. The cryogenic liquid turbine, as recited in claim 1, wherein said nozzle assembly comprises: a nozzle turntable, a nozzle chassis, a nozzle cover plate, a nozzle compression plate, a nozzle compression flange, nozzle vanes, and a nozzle vane stagger adjusting mechanism; wherein, said nozzle assembly is connected to a seal gas part by said nozzle compression flange, so as to be connected to said machine housing; said nozzle vanes are mounted rotatably between said nozzle chassis and said nozzle cover plate by a cylindrical pin; said nozzle turntable is connected rotatably in an axial direction to said nozzle chassis, and is connected to said nozzle vane stagger adjusting mechanism that passes through said volute.

6. The cryogenic liquid turbine, as recited in claim 5, wherein, said nozzle vanes are compressed by said nozzle compression plate through a disc spring having an adjustable margin, and said nozzle compression plate uses said disc spring to adjust a compactness degree of said nozzle vanes.

7. The cryogenic liquid turbine, as recited in claim 1, wherein, a non-impeller end of said shaft is connected to a coupling; a generator, a pump, or a blower is used to brake said cryogenic liquid turbine.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The FIGURE is a structure diagram for assembling a cryogenic liquid turbine of the present invention.

(2) 1. a volute, 2. an thermal insulation pad, 3. a cold box, 4. a seal gas part, 5. a shaft seal, 6. an oil seal, 7. a connector, 8. a lifting eye bolt, 9. a machine housing, 10. shaft, 11. an oil outlet, 12. a thrust journal bearing, 13. a gas seal channel, 14. a nozzle turntable, 15. a bolt, 16. a positioning pin, 17. a nozzle chassis, 18. nozzle vanes, 19. an impeller, 20. a diffuser pipe, 21. an impeller fastening screw, 22. impeller shroud side seal, 23. a nozzle cover plate, 24. a cylindrical pin, 25. a disc spring, 26. a nozzle compression plate, and 27. a nozzle compression flange.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

(3) Referring to FIGURE and embodiments, the present invention is further described in details as follows.

(4) Referring to the FIGURE, a cryogenic liquid turbine comprises: a machine housing 9, a thrust journal bearings 12, a rotor, a nozzle unit, a volute 1, a diffuser pipe 20, a sealing element, and a cold box 3;
wherein, the machine housing 9 comprises: a lifting eye bolt 8, an oil outlet 11, a bearing temperature measuring hole, a bearing oil supplying hole and an air supplying hole of a gas seal, which are all connected by a connector 7 to corresponding pipelines;
wherein the rotor comprises: a shaft 10, an impeller 19, and a coupling;
wherein the nozzle assembly comprises: a nozzle turntable 14, a nozzle chassis 17, a nozzle cover plate 23, a nozzle compression plate 26, a nozzle compression flange 27, nozzle vanes 18, and a nozzle adjusting mechanism;
wherein the sealing element comprises: a impeller shroud side seal 22, a shaft seal 5, a seal gas part 4, and an oil seal 6.

(5) The shaft 10 is fixed rotatably in the machine housing 9 by the two thrust journal bearings 12 that are respectively on a left side and on a right side, for guaranteeing that the rotor operates stably and reliably with restrained axial and radial displacement. A triangular polygon section of shaft 10 is fitted to triangular polygon hole of the impeller 19, and both are fixed by an impeller fastening screw 21, and the other end of the shaft 10 is fitted with the coupling. Therefore, various braking forms are applicable. The impeller 19 is a shrouded, or a semi-shrouded type impeller as well as an unshrouded impeller. The rotor avoids an oil seal in a slinger structure and reduces a use of a rotating part, for improving operation reliability. Cryogenic liquid radially enters into impeller, and axially flows out at impeller outlet, which meets the condition that near-zero swirling velocity at impeller outlet is produced to reduce flow loss inside the impeller 19.

(6) The nozzle compression flange 27 of the nozzle unit compresses axially the nozzle assembly to the seal gas part 4 by a bolt 15, so as to be axially fixed on the machine shell 9; the nozzle chassis 17 is axially fixed on the seal gas part 4 by the bolt 15; the nozzle vane 18 is mounted rotatably between the nozzle chassis 17 (assembled with the nozzle turntable 14) and the nozzle 23 by a cylindrical pin 24, and is compressed by the disc spring 25 through the nozzle compression plate 26 to keep a certain pre-compactness; the nozzle turntable 14 is fitted rotatably to the nozzle chassis 17 by a pin 16 to adjust nozzle vane stagger angle through an adjusting mechanism; the impeller shroud side seal 22 is fixed axially on the nozzle compression flange 27 by a bolt; the shaft seal 5 is fixed on the seal gas part 4 by a bolt; in such a manner, the nozzle assembly, the impeller shroud side seal 22, and the shaft seal 5 of a impeller disk side are combined as a whole to be installed and fixed with the machine housing 9.

(7) Referring to FIGURE, the oil seal 6 is fixed axially to the machine housing 9. The oil seal 6 seals the oil through seal teeth thereon and seal gas. The diffuser pipe 20 is fixed axially to the volute 1, for reducing flow velocity at the impeller outlet and reducing flow loss.

(8) An overall design scheme of the cryogenic liquid turbine is that impeller end of rotor and the nozzle assembly are included in the volute 1, for preventing that a low temperature liquid directly contacts the machine housing 9 exposed in an atmospheric environment, and for reducing a coldness loss to a maximum extent; meanwhile, an thermal insulation pad 2 is used between the volute 1 and the machine housing 9 to insulate heat, and the volute 1 is put into a perlite cold box 3 to insulate the heat, for reducing a cold loss.

(9) An operating principle of the present invention is described as follows.

(10) By using a throttling effect of low-temperature and high-pressure liquefied gases, pressure head of the low-temperature and high-pressure liquefied gases that flows into the cryogenic liquid turbine is converted to a mechanical energy, and is output by the shaft 10, in such a manner that a wasted pressure head is recovered. In the meantime, vaporization of liquefied gas is suppressed effectively or avoided completely, in such a manner that gas extraction rate of air separation unit is increased, and a system power consumption is reduced.

(11) After the low-temperature and high-pressure liquefied gases flow into the volute 1 through the pipeline, the liquid is uniformly distributed over the nozzle ring through a flow passage inside the volute 1. After passing through the nozzle vane passage 18, the liquid is accelerated, and pressure head is converted into a kinetic energy. The liquid radially enters into the impeller 19 as shown in the FIGURE, the liquid drives the impeller to rotate and does mechanical work to the impeller 19, in such a manner, the pressure head of the liquid thereof is converted into power of shaft rotating at a high speed. After the liquid pressure is reduced, to the level required by the technological process, the liquid is discharged from the exit of the impeller 19. The impeller 19 is connected to and fixed with the shaft 10 by a triangular polygon matching. Because moment of inertia of the triangular polygon matching is relatively large and strength as well as a stiffness of the triangular polygon matching are high, a good stress distribution of the structure is guaranteed, so the triangular polygon shaft is suitable for the cryogenic liquid turbine having characteristics that rotational speed is high and shaft power is relatively large. After the liquid flows from the impeller 19 into the diffuser pipe 20, liquid velocity is gradually reduced, the flow loss is reduced, and its static pressure is increased.

(12) A method for solving a problem of a cold barrier of the cryogenic liquid turbine comprises steps of: putting the rotor impeller end and the nozzle assembly inside the volute 1, and putting the whole section of the volute 1 is into the perlite cold box 3 to insulate the heat, in such a manner that the low temperature liquid is not directly contacted to the machine housing 9 exposed in the atmospheric environment, so the coldness loss is reduced in the maximum extent; utilizing the insulation pad 2 between the volute 1 and the machine housing 9 at a same time to insulate the heat, for reducing the cold loss.

(13) One skilled in the art will understand that the embodiment of the present invention as shown in the drawings and described above is exemplary only and not intended to be limiting.

(14) It will thus be seen that the objects of the present invention have been fully and effectively accomplished. Its embodiments have been shown and described for the purposes of illustrating the functional and structural principles of the present invention and is subject to change without departure from such principles. Therefore, this invention includes all modifications encompassed within the spirit and scope of the following claims.