A twin-screw hydraulic turbine device

Abstract

A twin-screw hydraulic turbine device includes a housing, a first rotor, and a second rotor. The housing has a working chamber, a high-pressure inlet, and two low-pressure outlets. The two ends of the first rotor and the two ends of the second rotor are rotatably mounted on the housing. The middle portion of the first rotor has first and second helical tooth sections with opposite directions of rotation spaced apart, and the middle portion of the second rotor has third and fourth helical tooth sections with opposite directions of rotation spaced apart. The first and third helical tooth sections mesh to form a first turbine section, and the second and fourth helical tooth sections mesh to form a second turbine section. Both the first and second turbine sections are located within the working chamber. The high-pressure inlet is adjacent to one end of the first and second turbine sections, and the two low-pressure outlets are adjacent to the other ends of the first and second turbine sections, respectively. This invention eliminates the need for a sealing structure on the high-pressure liquid side and reduces the axial force on the rotor.

Description

Technical Field

[0001] The utility model relates to the field of fluid machinery, in particular to a hydraulic turbine device suitable for recovering pressure energy of high-pressure liquid. Background Art

[0002] In the process of petrochemical, steel metallurgy and seawater desalination, there are many processes where high-pressure fluids are reduced to the required low pressure through pressure reducing valves, or the discharged waste fluids still have a high pressure. During the process of pressure reduction and discharge, a large amount of fluid pressure energy is converted into heat energy and dissipated into the environment, causing a large amount of pressure loss of high-pressure fluids.

[0003] Hydraulic turbine is the earliest technology developed and applied in the field of liquid pressure energy recovery. It uses the reverse rotation of centrifugal pump to convert the pressure energy of fluid into mechanical energy, and mechanical energy into electrical energy or pressure energy. In the field of high-pressure and ultra-high-pressure liquid pressure energy recovery, twin-screw pumps have the advantages of stable conveying medium, small pressure pulsation and small vibration, but they face problems such as difficult sealing at the high-pressure end and poor screw stress. Summary of the invention

[0004] The utility model aims to overcome the shortcomings of the conventional twin-screw pump for recovering high-pressure liquid pressure, such as the difficulty in sealing the high-pressure liquid side and the poor force on the rotor, and to provide a twin-screw hydraulic turbine device which does not require a sealing structure on the high-pressure liquid side and has a small axial force on the rotor.

[0005] A twin-screw hydraulic turbine device according to an embodiment of the utility model comprises a shell, a first rotor and a second rotor; the shell has a working chamber, a high-pressure liquid inlet and two low-pressure liquid outlets, the high-pressure liquid inlet and the two low-pressure liquid outlets are respectively connected to the working chamber; the two ends of the first rotor and the two ends of the second rotor are respectively rotatably mounted on the shell, the middle part of the first rotor is provided with a first spiral tooth surface segment and a second spiral tooth surface segment with opposite rotation directions, the middle part of the second rotor is provided with a third spiral tooth surface segment and a fourth spiral tooth surface segment with opposite rotation directions, the first spiral tooth surface segment is meshed with the third spiral tooth surface segment to form a first turbine part, the second spiral tooth surface segment is meshed with the fourth spiral tooth surface segment to form a second turbine part; the first turbine part and the second turbine part are both arranged in the working chamber; the high-pressure liquid inlet is adjacent to one end of the first turbine part and the second turbine part, so that the liquid flowing in from the high-pressure liquid inlet can enter the first turbine part and the second turbine part at the same time; the two low-pressure liquid outlets are adjacent to the other end of the first turbine part and the other end of the second turbine part, respectively.

[0006] In the above-mentioned twin-screw hydraulic turbine device, the first helical tooth surface segment and the second helical tooth surface segment have the same size and tooth shape, and the third helical tooth surface segment and the fourth helical tooth surface segment have the same size and tooth shape.

[0007] Compared with the prior art, the utility model has the following advantages and characteristics:

[0008] 1. A twin-screw hydraulic turbine device in an embodiment of the utility model eliminates the sealing structure on the high-pressure liquid side, reduces leakage, and improves turbine efficiency;

[0009] 2. The two groups of turbine parts in the embodiment of the utility model are arranged opposite to each other, and the axial forces of the two groups of turbine parts are opposite and offset each other, thereby reducing the axial force of the rotor. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 A schematic diagram of the structure and appearance of the first rotor and the second rotor in an embodiment of the utility model is shown.

[0011] Figure 2 A schematic diagram of the internal structure of a twin-screw hydraulic turbine device according to an embodiment of the utility model is shown.

[0012] Figure 3 The utility model shows a high-pressure liquid inlet and two low-pressure liquid outlets of a twin-screw hydraulic turbine device in an embodiment of the utility model.

[0013] Figure 4 A structural schematic diagram of a partition plate according to an embodiment of the utility model is shown. DETAILED DESCRIPTION

[0014] See also Figures 1 to 3 A twin-screw hydraulic turbine device according to an embodiment of the utility model includes a housing 1 , a first rotor 21 and a second rotor 22 .

[0015] The housing 1 has a working chamber 10 , a high-pressure liquid inlet 11 and two low-pressure liquid outlets 12 . The high-pressure liquid inlet 11 and the two low-pressure liquid outlets 12 are respectively connected to the working chamber 10 .

[0016] In this embodiment, the shell 1 includes a left end cover 1a, a left end seat 1b, a main body 1c, a right end seat 1d and a right end cover 1e which are connected in sequence. The working chamber 10 is defined by the left end seat 1b, the main body 1c and the right end seat 1c. The high-pressure liquid inlet 11 is located in the middle of the shell 1, and the two low-pressure liquid outlets 12 are located on both sides of the shell 1. The high-pressure liquid inlet 11 and the two low-pressure liquid outlets 12 can be set on the top surface, bottom surface or side surface of the shell 1. The utility model does not limit this. Specifically, the high-pressure liquid inlet 11 is set on the main body 1c, and the two low-pressure liquid outlets 12 are respectively set on the left end seat 1b and the right end seat 1d.

[0017] Both ends of the first rotor 21 and the second rotor 22 are rotatably mounted on the housing 1. The central axis of the first rotor 21 and the central axis of the second rotor 22 are parallel to each other. Either end of the first rotor 21 or the second rotor 22 extends out of the corresponding end cover to connect to external equipment and output power. In this embodiment, one end of the first rotor 21 extends out of the right end cover 1e. Each end of each rotor is provided with a bearing 3, and the bearings 3 at both ends of each rotor are respectively mounted on the left end seat 1b and the right end seat 1d. Preferably, the above-mentioned bearing 3 includes a radial bearing and a thrust bearing, the radial bearing provides radial support and fixation, and the thrust bearing provides axial positioning.

[0018] The first rotor 21 is provided with a first helical tooth surface segment 211 and a second helical tooth surface segment 212 of opposite rotation directions at intervals in the middle part, and the second rotor 22 is provided with a third helical tooth surface segment 221 and a fourth helical tooth surface segment 222 of opposite rotation directions at intervals in the middle part, the first helical tooth surface segment 211 is meshed with the third helical tooth surface segment 221 to form a first turbine section, and the second helical tooth surface segment 212 is meshed with the fourth helical tooth surface segment 222 to form a second turbine section; the first turbine section and the second turbine section are both arranged in the working chamber 10. Preferably, the first helical tooth surface segment 211 and the second helical tooth surface segment 212 have the same size and tooth profile and are symmetrically arranged, and the third helical tooth surface segment 221 and the fourth helical tooth surface segment 222 have the same size and tooth profile and are symmetrically arranged. The above-mentioned size refers to the length, outer diameter, tooth width, tooth thickness, etc. of the helical tooth surface segment.

[0019] In this embodiment, a shaft seal 4 is installed at each end of each rotor to seal the working chamber 10 to prevent liquid from leaking outward. The bearings installed at each end of each rotor are located outside the shaft seal at the same end (i.e., the side away from the working chamber 10). The shaft seals 4 at both ends of each rotor are installed on the left end seat 1b and the right end seat 1d respectively. The first rotor 21 includes a first intermediate shaft section 213 located between the first spiral tooth surface section 211 and the second spiral tooth surface section 212, and the second rotor 22 includes a second intermediate shaft section 223 located between the third spiral tooth surface section 221 and the fourth spiral tooth surface section 222; the outer diameter of the first intermediate shaft section 213 is smaller than the outer diameters of the first spiral tooth surface section 211 and the second spiral tooth surface section 212, and the outer diameter of the second intermediate shaft section 223 is smaller than the outer diameters of the third spiral tooth surface section 221 and the fourth spiral tooth surface section 224. Optionally, the outer diameter and length of the first intermediate shaft section 213 and the second intermediate shaft section 223 are equal.

[0020] The high-pressure liquid inlet 11 is adjacent to one end of the first turbine part and the second turbine part (i.e., adjacent to the first intermediate shaft section 213 and the second intermediate shaft section 223), so that the liquid flowing in from the high-pressure liquid inlet 11 can enter the first turbine part and the second turbine part at the same time; the two low-pressure liquid outlets 12 are respectively adjacent to the other end of the first turbine part and the other end of the second turbine part.

[0021] See also Figure 4 . Optionally, a twin-screw hydraulic turbine device of the present embodiment includes a partition plate 5, which is arranged in the working chamber 10 to separate the first turbine section from the second turbine section and form an axial inlet for high-pressure liquid of the first turbine section and an axial inlet for high-pressure liquid of the second turbine section. In a specific embodiment, the partition plate 5 is arranged below the first intermediate shaft section 213 and the second intermediate shaft section 223. The side surface 50 of the partition plate 5 is connected to the inner wall of the working chamber 10, and the side surface 50 of the partition plate 5 is provided with a first groove 51 for accommodating the first intermediate shaft section 213 and a second groove 52 for accommodating the second intermediate shaft section 223.

[0022] Optionally, a twin-screw hydraulic turbine device of this embodiment further includes a pair of synchronous gears 6 meshing with each other, and the pair of synchronous gears 6 are respectively installed at any one end of the first rotor 21 and the second rotor 22. The gear ratio of the synchronous gear 6 is the same as the gear ratio of the helical tooth surface segments of the two rotors, and the torque of the second rotor 22 can be transmitted to the first rotor 21.

[0023] In actual operation, the high-pressure liquid enters the inter-tooth volume of the first turbine part and the second turbine part through the high-pressure liquid inlet 11, gradually releases the pressure energy, and drives the first rotor 21 and the second rotor 22 to rotate. As the rotors continue to rotate, the inter-tooth volume of the first spiral tooth surface segment 211 and the third spiral tooth surface segment 221 and the inter-tooth volume of the second spiral tooth surface segment 212 and the fourth spiral tooth surface segment 222 gradually increase, and the high-pressure liquid enclosed in the inter-tooth volume expands, and the low-pressure liquid after decompression is discharged from the two low-pressure liquid outlets 12. Among them, the torque generated by the rotation of the second rotor 22 is transmitted to the first rotor 21 through the synchronous gear 6. The part of the first rotor 21 that extends out of the end cover can be connected to the device to be driven or the power generation device, and finally the pressure energy of the high-pressure liquid is converted into mechanical kinetic energy or electrical energy.

[0024] The utility model can be used for efficiently recovering the pressure energy of high-pressure liquid, is adaptable to different rotation speeds and pressures, and has a wide range of applications.

Claims

1. A twin-screw hydraulic turbine device, characterized in that: comprising a housing, a first rotor and a second rotor; The shell has a working chamber, a high-pressure liquid inlet and two low-pressure liquid outlets, and the high-pressure liquid inlet and the two low-pressure liquid outlets are respectively connected to the working chamber; The two ends of the first rotor and the two ends of the second rotor are rotatably mounted on the housing, respectively; a first helical tooth surface segment and a second helical tooth surface segment with opposite rotation directions are arranged at intervals in the middle of the first rotor; a third helical tooth surface segment and a fourth helical tooth surface segment with opposite rotation directions are arranged at intervals in the middle of the second rotor; the first helical tooth surface segment meshes with the third helical tooth surface segment to form a first turbine portion; the second helical tooth surface segment meshes with the fourth helical tooth surface segment to form a second turbine portion; the first turbine portion and the second turbine portion are both arranged in the working chamber; The high-pressure liquid inlet is adjacent to one end of the first turbine part and the second turbine part, so that the liquid flowing in from the high-pressure liquid inlet can enter the first turbine part and the second turbine part at the same time; the two low-pressure liquid outlets are adjacent to the other end of the first turbine part and the other end of the second turbine part respectively.

2. A twin-screw hydraulic turbine device according to claim 1, characterized in that: The first helical tooth surface segment has the same size and tooth shape as the second helical tooth surface segment, and the third helical tooth surface segment has the same size and tooth shape as the fourth helical tooth surface segment.

3. A twin-screw hydraulic turbine device according to claim 1 or 2, characterized in that: A shaft seal is installed at each end of each rotor to seal the working chamber.

4. A twin-screw hydraulic turbine device according to claim 3, characterized in that: Each end of each rotor is sleeved with a bearing, and the bearings installed on each end of each rotor are located outside the shaft seal at the same end.

5. A twin-screw hydraulic turbine device according to claim 1, characterized in that: The twin-screw hydraulic turbine device comprises a pair of synchronous gears meshing with each other, and the pair of synchronous gears are respectively installed at any one end of the first rotor and the second rotor.

6. A twin-screw hydraulic turbine device according to claim 1, characterized in that: The housing comprises a left end cover, a left end seat, a main body, a right end seat and a right end cover which are connected in sequence; The working chamber is defined by the left end seat, the main body and the right end seat; The high-pressure liquid inlet is arranged on the main body, and the two low-pressure liquid outlets are arranged on the left end seat and the right end seat respectively.

7. A twin-screw hydraulic turbine device according to claim 6, characterized in that: Any one end of the first rotor or the second rotor extends out of the corresponding end cover.

8. A twin-screw hydraulic turbine device according to claim 1, characterized in that: The first rotor comprises a first intermediate shaft segment between the first helical tooth surface segment and the second helical tooth surface segment, and the second rotor comprises a second intermediate shaft segment between the third helical tooth surface segment and the fourth helical tooth surface segment; The outer diameter of the first intermediate shaft segment is smaller than the outer diameters of the first helical tooth surface segment and the second helical tooth surface segment, and the outer diameter of the second intermediate shaft segment is smaller than the outer diameters of the third helical tooth surface segment and the fourth helical tooth surface segment.

9. A twin-screw hydraulic turbine device according to claim 8, characterized in that: The twin-screw hydraulic turbine device includes a partition plate, which is arranged in the working chamber to separate the first turbine part from the second turbine part and form an axial high-pressure liquid inlet for the first turbine part and an axial high-pressure liquid inlet for the second turbine part; the side of the partition plate is connected to the inner wall of the working chamber, and the side of the partition plate is provided with a first groove for accommodating the first intermediate shaft segment and a second groove for accommodating the second intermediate shaft segment.

10. A twin-screw hydraulic turbine device according to claim 8, characterized in that: The first intermediate shaft section and the second intermediate shaft section have the same outer diameter and length.

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