A special generator applicable to the utilization of natural gas residual pressure

Abstract

The present invention relates to a special generator suitable for the utilization of residual pressure of natural gas, belonging to the technical field of natural gas power generation. It is characterized in that the power device is connected to the natural gas output pipeline, the rotating shaft of the power device is connected to the rotor shaft of the generator, bearings are installed at both ends of the rotor shaft of the generator, a non-magnetic isolation sleeve is installed between the power generation coil and the magnetic steel, the magnetic steel is connected to the rotor shaft of the generator by interference fit, the natural gas drives the internal rotating shaft of the power device to rotate, the movement of the rotating shaft is converted into the rotational movement of the rotor shaft of the generator, and then drives the magnetic steel to rotate to generate electric energy, which passes through the power transmission terminal and is connected to the power generation coil for outputting electric energy; the sealing form of the present invention adopts static sealing, which has the characteristics of good sealing performance, simple structure, high power generation efficiency and can safely and effectively output electric energy to the outside.

Description

Technical Field

[0001] The present invention relates to the technical field of natural gas power generation, and particularly to a special generator suitable for the utilization of natural gas residual pressure. Background Art

[0002] During the process of natural gas production, gathering, and transportation, the pressure at the wellhead of the gas well or the gathering station is often relatively high. Currently, most of them throttle and reduce the pressure of natural gas at the wellhead or the gathering station to meet the requirements of the medium and low-pressure gathering and transportation process. However, throttling and pressure reduction not only greatly waste the energy existing in the form of pressure energy, but also cause the temperature of natural gas to drop during the throttling and pressure reduction process. When the temperature drops to the condition for forming hydrates, it will cause the problem of the pipeline system being blocked by hydrates. The existing method uses heating to increase the temperature of natural gas to prevent the formation of hydrates, which significantly increases the gathering and transportation cost. If this part of the residual pressure energy can be recycled and the recycled energy is converted into electric energy for use in the gathering and transportation heating process, etc., it will bring good economic benefits and at the same time contribute to energy conservation and emission reduction.

[0003] The technology for the utilization of natural gas residual pressure energy is to expand and reduce the pressure of natural gas, use the natural gas pressure to drive the power device to rotate and drive the generator to generate electricity, and realize the technology for recycling the residual pressure energy. As a clean energy, natural gas residual pressure energy will not cause any pollution to the environment and has obvious advantages. However, when the natural gas pressure drives the power device to be connected to a conventional generator, the generator must be separated from the natural gas environment. When connecting the output rotating shaft of the pressure-driven power device to the generator, it is necessary to solve the dynamic sealing problem well. It is relatively difficult to achieve dynamic sealing under high-pressure conditions. At the same time, in an inflammable and explosive environment, the explosion-proof performance requirements for the generator are extremely high, and existing generators cannot meet the above requirements well.

[0004] To solve the above problems, the present invention provides a new type of special generator for residual pressure utilization that avoids dynamic sealing technology, has the power generation coil filled with insulating oil for explosion protection, and can be maintenance-free at the same time. Summary of the Invention

[0005] The object of the present invention: To solve the dynamic sealing problem faced when the rotor shaft of the generator is docked with the rotating shaft of the power device, reduce the leakage of natural gas, reduce the maintenance cost, solve the explosion-proof problem of the natural gas pipeline generator, and realize the recycling of the pressure during the natural gas gathering and transportation process. The present invention particularly provides a special generator for the utilization of natural gas residual pressure. To achieve the above object, the technical solution adopted by the present invention is:

[0006] A special generator applicable to the utilization of natural gas residual pressure, comprising a power device, a rotating shaft, a generator rotor shaft, a diversion channel, balance hole A, a central diversion hole, balance hole B, a retaining ring, seal box A, positioning nut A, bearing A, seal box B, a generator housing, a left bearing box, stator insulation layer A, a through-wiring terminal, a locking nut, a metal shell, a conductive column, a sealing ring, an insulating layer, a limit stop, a power generation coil, a non-magnetic isolation sleeve, a magnetic steel, stator insulation layer B, seal box C, bearing B, positioning nut B, seal box D, a right bearing box, oil inlet A, an inner cylinder, oil inlet B, balance hole C, an outer cylinder, an oil filling plug, a balance piston, a natural gas pipeline, a check valve, characterized in that the upper part of the power device is connected to the natural gas output pipeline, the lower part of the power device is connected to the generator housing, the generator rotor shaft is connected to the rotating shaft of the power device for power transmission, bearings are installed at both ends of the generator rotor shaft, the positioning nut is fixed to the generator rotor shaft by threaded connection, the bearing box is provided with a radial hole, a check valve is installed at the radial hole, and seal boxes are installed on both sides of the bearing; the magnetic steel is connected to the generator rotor shaft by interference fit, a limit stop is installed at the left end of the magnetic steel, and the limit stop is fixed to the generator rotor shaft by threaded connection; the non-magnetic isolation sleeve is installed between the magnetic steel and the power generation coil, and sealing rings are installed at both ends of the non-magnetic isolation sleeve; the stator insulation layer is installed on both sides of the power generation coil, the outer cylinder is connected to the generator housing, the inner cylinder is installed between the outer cylinder and the right bearing box, the balance piston is installed between the inner cylinder and the outer cylinder, and the inner cylinder is connected to the lower natural gas pipeline.

[0007] A special generator applicable to the utilization of natural gas residual pressure, comprising a power device, a rotating shaft, a generator rotor shaft, a bearing box and a bearing, characterized in that: the generator rotor shaft is connected to the rotating shaft of the power device, the generator rotor shaft is of a hollow structure, diversion channels and balance holes are provided at both ends of the generator rotor shaft, bearings are installed at both ends of the generator rotor shaft, the bearing box is provided with a radial hole, a check valve is installed at the radial hole, and seal boxes are installed on both sides of the bearing for sealing.

[0008] The beneficial effects of adopting the above technical solution are: the generator rotor shaft and the power device are docked inside the natural gas pipeline, which can effectively avoid the dynamic sealing problem when a conventional generator is docked with the power device. Natural gas enters the cavities at both ends of the bearing through the diversion channel and the balance hole, so that the pressures on both sides of the bearing are in a balanced state. The bearing is lubricated with the check valve, and seal boxes are installed on both sides of the bearing for sealing, which can improve the service life of the bearing and ensure the reliability of the seal. At the same time, natural gas flows through the central diversion hole of the generator rotor shaft, which can reduce the external leakage of natural gas.

[0009] A special generator applicable to the utilization of natural gas residual pressure, including a stator insulation layer, a magnetic steel, a non-magnetic isolation sleeve, a generating coil, and a through-transmission terminal, is characterized in that: the inner surface of the generator housing is installed with a stator insulation layer and insulating materials, the magnetic steel is connected to the generator rotor shaft by an interference fit method, the non-magnetic isolation sleeve is installed between the generating coil and the magnetic steel, and sealing rings are installed at both ends of the non-magnetic isolation sleeve for sealing; insulating oil is injected into the cavity of the generating coil, a sealing ring is installed between the through-transmission terminal and the generator housing and fixed by threaded connection, and the lower part of the through-transmission terminal is connected to the generating coil.

[0010] The beneficial effects of adopting the above technical solutions are as follows: the non-magnetic isolation sleeve is installed between the generating coil and the magnetic steel, sealing rings are installed at both ends of the non-magnetic isolation sleeve, and insulating oil is injected into the cavity of the generating coil, so that the generating coil is in an insulating environment, preventing natural gas from contacting the generating coil, ensuring that the generating coil works in a good environment, and at the same time, the generating coil filled with insulating oil can prevent explosion.

[0011] A special generator applicable to the utilization of natural gas residual pressure, including an inner cylinder, an outer cylinder, a right bearing box, and a balance piston, is characterized in that: the outer cylinder is connected to the generator housing, there is an oil inlet at the right end of the right bearing box and the inner cylinder, and the balance piston is installed between the inner cylinder and the outer cylinder. Two closed cavities are formed at both ends of the balance piston, insulating oil is injected into the left side of the balance piston through an oil injection plug, an air inlet is opened at the right end of the inner cylinder, and the right side of the balance piston is communicated with natural gas.

[0012] The beneficial effects of adopting the above technical solutions are as follows: the sealing method of the balance piston adopts a combined seal, closed cavities are formed on both sides of the balance piston, insulating oil is injected into the left end of the balance piston through an oil injection plug, the right side of the balance piston is communicated with natural gas through a balance hole, and by moving the balance piston, it is ensured that the pressure in the oil cavity is always consistent with the natural gas pressure. In this way, the pressure inside and outside the non-magnetic isolation sleeve is theoretically zero, and the isolation sleeve realizes reliable isolation between natural gas and the generating coil.

[0013] A special generator applicable to the utilization of natural gas residual pressure, including a power device, and the power device can be a turbine motor or a screw motor, etc., and the specific implementation method can be determined according to the present invention and actual situations. Description of the Drawings

[0014] Figure 1 It is a schematic structural diagram of the generator part of the present invention.

[0015] Figure 2 is Figure 1 Schematic cross-sectional structure diagram in the A-A direction.

[0016] Figure 3 It is a schematic structural diagram of the through-wiring terminal of the present invention.

[0017] Figure 4 isFigure 1 Schematic diagram of the structure in the B direction.

[0018] Figure 5 Schematic diagram of the structure of the generator rotor shaft.

[0019] Figure 6 Schematic diagram of the structure of the inner cylinder of the generator.

[0020] Figure 7 Schematic diagram of the structure of the right bearing box of the generator.

[0021] In the figure: 1. Power device; 2. Rotating shaft; 3. Generator rotor shaft; 301. Diversion channel; 302. Balance hole A; 303. Central diversion hole; 304. Balance hole B; 4. Retaining ring; 5. Sealing box A; 6. Locking nut A; 7. Bearing A; 8. Sealing box B; 9. Generator housing; 10. Left bearing box; 11. Stator insulation layer A; 12. Through wiring terminal; 1201. Locking nut; 1202. Metal shell; 1203. Conductive column; 1204. Sealing ring; 1205. Insulation layer; 13. Limit stop; 14. Power generation coil; 15. Non-magnetic isolation sleeve; 16. Magnet; 17. Stator insulation layer B; 18. Sealing box C; 19. Bearing B; 20. Locking nut B; 21. Sealing box D; 22. Right bearing box; 2201. Oil inlet A; 23. Inner cylinder; 2301. Oil inlet B; 2302. Balance hole C; 24. Outer cylinder; 25. Oil filling plug; 26. Balance piston; 27. Natural gas pipeline; 28. Check valve. Specific embodiments

[0022] The embodiments of the technical solution of the present invention will be described in detail below with reference to the accompanying drawings. The present invention is not limited by the following embodiments, and the specific implementation manners can be determined according to the present invention and the actual situation. The positional relationships such as up, down, left, and right are determined according to the layout direction of the attached Figure 1 drawings of the specification.

[0023] As shown in the attached drawings, an embodiment of the present invention provides a special generator applicable to the utilization of natural gas residual pressure, including a power device 1, a rotating shaft 2, a generator rotor shaft 3, a diversion channel 301, a balance hole A 302, a central diversion hole 303, a balance hole B 304, a retaining ring 4, a seal box A 5, a positioning nut A 6, a bearing A 7, a seal box B 8, a generator housing 9, a left bearing box 10, a stator insulation layer A 11, a through-wiring terminal 12, a locking nut 1201, a metal shell 1202, a conductive column 1203, a sealing ring 1204, an insulation layer 1205, a limit stop 13, a power generation coil 14, a non-magnetic isolation sleeve 15, a magnetic steel 16, a stator insulation layer B 17, a seal box C 18, a bearing B 19, a positioning nut B 20, a seal box D 21, a right bearing box 22, an oil inlet A 2201, an inner cylinder 23, an oil inlet B 2301, a balance hole C 2302, an outer cylinder 24, an oil filling plug 25, a balance piston 26, a natural gas pipeline 27, and a one-way valve 28. The upper part of the power device 1 is connected to the natural gas pipeline, and the lower part is connected to the generator housing 9. The rotating shaft 2 is connected to the generator rotor shaft 3 for power transmission. Bearings A 7 and B 19 are respectively installed at both ends of the generator rotor shaft 3. A positioning nut A 6 is installed on the left side of the bearing A 7 for axial positioning. The left bearing box 10 and the right bearing box 22 are provided with radial holes, and a one-way valve 28 is installed at the radial holes to inject oil into the bearings. Seal boxes A 5 and B 8 are installed on both sides of the bearing A 7 for sealing, and the two bearings are symmetrically arranged. A diversion channel 301 is provided at the left end of the generator rotor shaft 3. The generator rotor shaft 3 is a hollow structure. Natural gas enters the generator rotor shaft 3 from the diversion channel 301, passes through the central diversion hole 303, and a small amount of natural gas flows through the balance hole A 302 and the balance hole B 304, so that the pressures on both sides of the bearing are in a balanced state. A sealing ring is installed between the left bearing box 10 and the generator housing 9. An insulating material is installed on the inner wall of the generator housing 9. A sealing ring 1204 is installed between the through-wiring terminal 12 and the generator housing 9 and fixed by threaded connection. The magnetic steel 16 and the generator rotor shaft 3 are assembled by interference fit. A limit stop 13 is installed at the left end of the magnetic steel 16, and the limit stop 13 and the generator rotor shaft 3 are fixed by threaded connection. A non-magnetic isolation sleeve 15 is installed between the power generation coil 14 and the magnetic steel 16, and both ends of the non-magnetic isolation sleeve 15 are sealed by sealing rings. Insulating oil is injected into the cavity of the power generation coil 14 through the oil filling plug 25. Stator insulation layers A 11 and B 17 are respectively installed at both ends of the power generation coil 14. Oil inlets A 2201 and B 2301 are respectively provided on the right bearing box 22 and the inner cylinder 23. A sealing ring is installed at the joint surface between the right bearing box 22 and the inner cylinder 23 for sealing, and a sealing ring is also installed between the joint surface of the right end cover 22 and the generator housing 9 for sealing.The balance piston 26 is installed between the inner cylinder 23 and the outer cylinder 24. Two sealed annular cavities are formed at the left and right ends of the balance piston 26. The sealing method of the balance piston 26 adopts a combined seal. Insulating oil is injected into the left end of the balance piston 26 through the oil filling plug 25. The right end of the balance piston 26 is connected to natural gas through the balance hole C2302. By moving the balance piston 26, it is ensured that the pressure in the oil cavity is always the same as the natural gas pressure. In this way, the pressure inside and outside the non-magnetic isolation sleeve 15 is theoretically zero, realizing reliable isolation between natural gas and the power generation coil 14. The outer cylinder 24 is connected to the natural gas pipeline 27.

[0024] The above technical features constitute the best implementation case of the present invention. It has strong adaptability and the best implementation effect. Non-essential technical features can be increased or decreased according to actual technical needs to meet the requirements of different situations.

[0025] The usage process of the implementation case of the present invention:

[0026] The working process of a special generator applicable to the utilization of natural gas residual pressure in the present invention is as follows: Natural gas has a certain flow rate and pressure in the gathering and transportation pipeline. When the high-pressure gas in the natural gas pipeline enters the power device 1, the high-pressure gas drives the rotating shaft 2 of the power device to generate a rotational motion. The rotating shaft 2 is connected to the generator rotor shaft 3 for power transmission. Bearings A7 and B19 are respectively installed at both ends of the generator rotor shaft 3. The left bearing housing 10 and the right bearing housing 22 are provided with radial holes, and check valves 28 are installed at the radial holes for oil injection into the bearings. Sealing boxes are installed on both sides of the bearing 7 for sealing. The generator rotor shaft 3 and the magnetic steel 16 are assembled by interference fit. The motion of the rotating shaft 2 is converted into the motion of the generator rotor shaft 3, and then the magnetic steel 16 is driven to rotate. Using the principle of electromagnetic induction, electric energy is generated to realize power generation by the generator. Natural gas flows in from the diversion channel 301 and flows through the diversion hole 303 in the central hole of the generator rotor shaft 3, which can reduce the external leakage of natural gas. There is no dynamic sealing device at all, and the generator magnetic steel 16 rotates inside the non-magnetic isolation sleeve 15. Balance holes A302 and B304 are respectively provided at both ends of the generator rotor shaft 3 to ensure that the pressures on both sides of the bearing are in a balanced state and improve the reliability of the bearing seal. Insulating oil is injected into the left end of the balance piston 26 through the oil filling plug 25. The right end of the balance piston 26 is connected to natural gas through the balance hole C2302. By moving the balance piston 26, it is ensured that the pressure in the oil cavity is always the same as the natural gas pressure. In this way, the pressure inside and outside the non-magnetic isolation sleeve 15 is theoretically zero, realizing reliable isolation between natural gas and the power generation coil 14. The electric energy generated by the power generation coil 14 is output through the transmission terminal 12.

[0027] Finally, it should be noted that the above-described embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A special generator applicable to the utilization of natural gas residual pressure, Characterized in that: Including a power device (1), a rotating shaft (2), a generator rotor shaft (3), a diversion channel (301), a balance hole A (302), a central diversion hole (303), a balance hole B (304), a retaining ring (4), a seal box A (5), a positioning nut A (6), a bearing A (7), a seal box B (8), a generator housing (9), a left bearing box (10), a stator insulation layer A (11), a through wiring terminal (12), a locking nut (1201), a metal shell (1202), a conductive post (1203), a sealing ring (1204), an insulation layer (1205), a limit stop (13), a generating coil (14), a non-magnetic isolation sleeve (15), a magnetic steel (16), a stator insulation layer B (17), a seal box C (18), a bearing B (19), a positioning nut B (20), a seal box D (21), a right bearing box (22), an oil inlet A (2201), an inner cylinder (23), an oil inlet B (2301), a balance hole C (2302), an outer cylinder (24), an oil filling plug (25), a balance piston (26), a natural gas pipeline (27), a check valve (28). The upper part of the power device (1) is connected to the natural gas pipeline, and the lower part is connected to the generator housing (9). The rotating shaft (2) is connected to the generator rotor shaft (3) for transmitting power. Bearings A (7) and B (19) are respectively installed at both ends of the generator rotor shaft (3), and a positioning nut A (6) is installed on the left side of the bearing A (7) for axial positioning. The left bearing box (10) and the right bearing box (22) are provided with radial holes, and check valves (28) are installed at the radial holes for lubricating the bearings. Seal boxes A (5) and B (8) are installed on both sides of the bearing A (7) for sealing, and the two bearings are symmetrically arranged. A diversion channel (301) is provided at the left end of the generator rotor shaft (3). The generator rotor shaft (3) is a hollow structure. Natural gas enters the generator rotor shaft (3) through the diversion channel (301), passes through the central diversion hole (303), and a small amount of natural gas flows through the balance hole A (302) and the balance hole B (304) to keep the pressures on both sides of the bearing balanced. A sealing ring is installed between the left bearing box (10) and the generator housing (9). The inner wall of the generator housing (9) is equipped with insulating materials. The through power transmission terminal (12) includes a locking nut (1201), a metal shell (1202), a conductive post (1203), a sealing ring (1204), and an insulation layer (1205). The through power transmission terminal (12) is fixed to the generator housing (9) by threaded connection. A sealing ring (1204) is installed between the through power transmission terminal (12) and the generator housing (9). An insulation layer (1205) is installed between the conductive post (1203) and the metal shell (1202). The lower part of the through power transmission terminal (12) is connected to the generating coil (14).The permanent magnet (16) is assembled with the generator rotor shaft (3) by interference fit. A limit stop block (13) is installed at the left end of the permanent magnet (16), and the limit stop block (13) is fixed to the generator rotor shaft (3) by threaded connection; A non-magnetic isolation sleeve (15) is installed between the power generation coil (14) and the permanent magnet (16). Both ends of the non-magnetic isolation sleeve (15) are sealed by sealing rings. The cavity of the power generation coil (14) is filled with insulating oil through an oil filling plug (25). Insulating stator insulation layer A (11) and stator insulation layer B (17) are installed at both ends of the power generation coil (14) respectively. An oil inlet A (2201) and an oil inlet B (2301) are respectively arranged on the right bearing box (22) and the inner cylinder (23). Sealing rings are installed at the joint surface of the right bearing box (22) and the inner cylinder (23) for sealing. Sealing rings are also installed between the joint surface of the right bearing box (22) and the generator housing (9); The balance piston (26) is installed between the inner cylinder (23) and the outer cylinder (24). Two closed annular cavities are formed at the left and right ends of the balance piston (26). The sealing method of the balance piston (26) is a combined seal. Insulating oil is injected into the left end of the balance piston (26) through an oil filling plug (25). The right end of the balance piston (26) is connected to natural gas through a balance hole C (2302). By moving the balance piston (26), it is ensured that the oil chamber pressure is always consistent with the natural gas pressure. In this way, the pressure inside and outside the non-magnetic isolation sleeve (15) is theoretically zero, realizing reliable isolation between natural gas and the power generation coil (14). The outer cylinder (24) is connected to the natural gas pipeline (27).;

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