Low-pressure shaft seal steam forced flow mixer

Abstract

The utility model discloses a low-pressure shaft seal steam forced flow mixer which comprises a thermocouple, a mixing pipeline, a desuperheating water pipe, a check valve, a plurality of stop valves, a pneumatic control valve, a filter and a three-way valve, the desuperheating water pipe is arranged at one end of the mixing pipeline, and the stop valves are arranged at the end, away from the mixing pipeline, of the desuperheating water pipe. The size of the multiple stop valves is matched with the size of the desuperheating water pipe, filters are arranged at the positions, close to the stop valves, of the desuperheating water pipe, the filters are symmetrically arranged relative to the desuperheating water pipe, pneumatic adjusting valves are arranged among the multiple stop valves, and the size of the pneumatic adjusting valves is matched with the size of the desuperheating water pipe. A check valve is arranged at the position, away from the stop valve, of the attemperation water pipe, and the end, away from the attemperation water pipe, of the check valve is fixedly connected with the mixed water pipe. The device is simple in structure, the temperature adjusting mode is simple and rapid, and damage to the whole device is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of cooling devices, in particular to a low-pressure shaft seal steam forced flow mixer. Background Art

[0002] A steam turbine, also known as a steam turbine engine, is a rotary steam power device. High-temperature and high-pressure steam passes through a fixed nozzle and becomes an accelerated airflow, which is then sprayed onto the blades, causing the rotor with the blades to rotate and perform work externally. Steam turbines are the main equipment in modern thermal power plants and are also used in the metallurgical industry, chemical industry, and ship power devices.

[0003] The turbine shaft seal system needs to meet certain conditions: the steam entering the low-pressure shaft seal of the turbine should maintain a superheat of more than 14°C; the lower limit of the temperature of the steam used for the low-pressure shaft seal of the turbine is 121°C, and the upper limit is 177°C. The shaft seal system controller is set at 150°C. The steam supply pressure is 24-28kPa (gauge pressure); in order to protect the rotor in the low-pressure shaft seal area from the damage caused by the thermal stress of the temperature difference between the low-pressure shaft seal and the rotor and the alternating thermal stress of the shaft seal temperature change to the turbine rotor, the temperature difference between the shaft seal steam temperature and the rotor surface temperature should be kept to a minimum, and the low-pressure shaft seal temperature should be kept stable to avoid large and frequent fluctuations; the shaft seal desuperheater should have good cooling performance.

[0004] In the prior art, the steam system of the low-pressure cylinder shaft seal of the steam turbine has problems such as large fluctuations in steam temperature after the water spray cooler, large deviations in the steam inlet temperature of each low-pressure cylinder shaft seal, and no suitable adjustment means. The steam supply temperature fluctuation of some shaft seals is as low as 101°C, which can easily lead to water in the low-pressure shaft seal steam, vacuum leakage of the unit, and increased vibration of the bearings. There are hidden dangers of unsafe accidents such as reduced unit life, increased dynamic and static friction, and vibration. Therefore, the utility model proposes a low-pressure shaft seal steam forced mixer to solve the above problems. Utility Model Content

[0005] The utility model aims to provide a low-pressure shaft seal steam forced flow mixer to solve the problems raised in the above background technology.

[0006] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a low-pressure shaft seal steam forced flow mixer, comprising a thermocouple, a mixing pipe, a cooling water pipe, a check valve, a stop valve, a pneumatic control valve, a filter and a three-way valve, a cooling water pipe is provided at one end of the mixing pipe, a plurality of stop valves are provided on the end of the cooling water pipe away from the mixing pipe, the sizes of the plurality of stop valves are adapted to the sizes of the cooling water pipe, a filter is provided on the cooling water pipe near the stop valve, the filter is symmetrically arranged relative to the cooling water pipe, a pneumatic control valve is provided between the plurality of stop valves, the sizes of the pneumatic control valves are adapted to the sizes of the cooling water pipe.

[0007] Preferably, a check valve is provided on the cooling water pipe at a position away from the stop valve, and one end of the check valve away from the cooling water pipe is fixedly connected to the mixing water pipe.

[0008] Preferably, a forced flow mixer body is provided on the mixing water pipe near the check valve, a steel plate is provided inside the forced flow mixer body, the size of the steel plate is adapted to the size of the forced flow mixer body, and a plurality of enhanced heat exchange holes are provided on the steel plate away from the forced flow mixer body.

[0009] Preferably, a mixing tooth is provided on the steel plate near the enhanced heat exchange hole, and the size of the mixing tooth is adapted to the size of the steel plate.

[0010] Preferably, a three-way valve is provided on one end of the mixing pipeline away from the forced flow mixer body, a pressure gauge is provided on the three-way valve, and a thermocouple is provided on the mixing pipeline near the three-way valve.

[0011] Compared with the prior art, the utility model has the following beneficial effects: the utility model has a simple structure, and the temperature adjustment method is simple and quick, which reduces the damage to the entire device. By strengthening the mixing hole, it is ensured that the steam can be mixed evenly in the forced mixer body, thereby completing the heat exchange. Through the three-way valve and the pressure gauge, it is ensured that the pressure of the entire device is visualized during the mixing process, thereby ensuring that the entire device maintains a certain degree of safety during the pressure change process. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram of the planar structure of the utility model;

[0013] Figure 2 For the utility model Figure 1 A in the middle is an enlarged top view of the structure;

[0014] Figure 3 For the utility model Figure 2 Enlarged structural diagram at B in the middle.

[0015] In the figure: 1. Thermocouple; 2. Mixing pipe; 3. Cooling water pipe; 4. Check valve; 5. Stop valve; 6. Pneumatic regulating valve; 7. Filter; 8. Three-way valve; 9. Pressure gauge; 10. Mixing tooth; 11. Enhanced heat exchange hole. DETAILED DESCRIPTION

[0016] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0017] In the description of the present invention, it should be noted that the terms "vertical", "up", "down", "horizontal", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0018] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0019] See also Figure 1-3 The utility model provides a technical solution: a low-pressure shaft seal steam forced flow mixer, comprising a thermocouple 1, a mixing pipe 2, a cooling water pipe 3, a check valve 4, a stop valve 5, a pneumatic regulating valve 6, a filter 7 and a three-way valve 8, a cooling water pipe 3 is provided at one end of the mixing pipe 2, a plurality of stop valves 5 are provided at the end of the cooling water pipe 3 away from the mixing pipe 2, the sizes of the plurality of stop valves 5 are adapted to the sizes of the cooling water pipe 3, a filter 7 is provided at a position near the stop valve 5 on the cooling water pipe 3, the filter 7 is symmetrically arranged relative to the cooling water pipe 3, a pneumatic regulating valve 6 is provided between the plurality of stop valves 5, the sizes of the pneumatic regulating valve 6 are adapted to the sizes of the cooling water pipe 3.

[0020] In this embodiment, a check valve 4 is provided on the cooling water pipe 3 at a position away from the stop valve 5, and one end of the check valve 4 away from the cooling water pipe 3 is fixedly connected to the mixing water pipe.

[0021] In this embodiment, a forced flow mixer body is provided on the mixing water pipe near the check valve 4, and a steel plate is provided inside the forced flow mixer body. The size of the steel plate is adapted to the size of the forced flow mixer body, and a plurality of enhanced heat exchange holes 11 are provided on the steel plate away from the forced flow mixer body.

[0022] In this embodiment, a mixing tooth is provided on the steel plate near the enhanced heat exchange hole 11, and the size of the mixing tooth 10 is adapted to the size of the steel plate.

[0023] In this embodiment, a three-way valve 8 is provided on the end of the mixing pipe 2 away from the forced flow mixer body, a pressure gauge 9 is provided on the three-way valve 8, and a thermocouple 1 is provided on the mixing pipe 2 near the three-way valve 8.

[0024] In this embodiment, a steel plate with an aspect ratio of 4:1 is twisted 180° (a is length, b is width, and c is thickness), and a square perforated steel plate with the same width and thickness as the twisted plate is installed at the end. A square mixing tooth 10 with a thickness of 1.5 times that of the steel plate is installed on one side of the end of the perforated steel plate. The whole is horizontally installed inside the low-pressure shaft seal steam pipeline. The twisted steel plate divides the steam pipeline into two parts along the axial direction. When the steam flows through the curved plate, the steam with a lower temperature in the lower part of the pipeline is guided to the upper part of the pipeline, and the steam with a higher temperature in the upper part of the pipeline is guided to the lower part of the pipeline. Since the steam with a high temperature has a low density and the steam with a low temperature has a high density, and since the steam in the upper part has a lower temperature and a higher density, and the steam in the lower part has a higher temperature and a lower density, the two parts of steam are further mixed and heat exchanged in the perforated steel plate at the back, and finally flow through the mixing tooth 10. The steam flow is vortex-perturbed at the mixing tooth 10, and the dry steam and the wet steam are further wrapped and mixed. Finally, the steam is fully diffused and mixed in the pipeline, thereby improving the uniformity of the steam.

[0025] Working principle: The staff controls the flow of gas or liquid in the cooling water pipe 3 through the stop valve 5 and the pneumatic regulating valve 6 on the cooling water pipe 3, removes impurities through the filter 7, and then flows into the mixing pipe 2 through the check valve 4, and then the steam flows through the mixing pipe 2 to the forced mixer body, and then through the enhanced heat exchange holes 11 and the mixing teeth 10, the steam at different temperatures is greatly mixed, and then monitored by the pressure gauge 9, and finally discharged through the action of the thermocouple 1.

[0026] It is worth noting that the entire device is controlled by a main control button. Since the device matched with the control button is a common device and belongs to the existing mature technology, its electrical connection relationship and specific circuit structure will not be described in detail here.

[0027] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A low-pressure shaft seal steam forced flow mixer, characterized in that: The invention comprises a thermocouple (1), a mixing pipe (2), a cooling water pipe (3), a check valve (4), a stop valve (5), a pneumatic regulating valve (6), a filter (7) and a three-way valve (8); a cooling water pipe (3) is arranged at one end of the mixing pipe (2); a plurality of stop valves (5) are arranged at the end of the cooling water pipe (3) away from the mixing pipe (2); the sizes of the plurality of stop valves (5) are matched with the sizes of the cooling water pipe (3); a filter (7) is arranged at a position close to the stop valve (5) on the cooling water pipe (3); the filter (7) is symmetrically arranged relative to the cooling water pipe (3); a pneumatic regulating valve (6) is arranged between the plurality of stop valves (5); the sizes of the pneumatic regulating valve (6) are matched with the sizes of the cooling water pipe (3).

2. A low-pressure shaft seal steam forced flow mixer according to claim 1, characterized in that: A check valve (4) is provided on the cooling water pipe (3) at a position away from the stop valve (5), and one end of the check valve (4) away from the cooling water pipe (3) is fixedly connected to the mixing water pipe.

3. A low-pressure shaft seal steam forced flow mixer according to claim 2, characterized in that: A forced flow mixer body is provided on the mixing water pipe near the check valve (4), a steel plate is provided inside the forced flow mixer body, the size of the steel plate is matched with the size of the forced flow mixer body, and a plurality of enhanced heat exchange holes (11) are provided on the steel plate at a position away from the forced flow mixer body.

4. A low-pressure shaft seal steam forced flow mixer according to claim 3, characterized in that: A mixing tooth is provided on the steel plate at a position close to the enhanced heat exchange hole (11), and the size of the mixing tooth (10) is adapted to the size of the steel plate.

5. A low-pressure shaft seal steam forced flow mixer according to claim 3, characterized in that: A three-way valve (8) is provided on one end of the mixing pipe (2) away from the forced flow mixer body, a pressure gauge (9) is provided on the three-way valve (8), and a thermocouple (1) is provided on the mixing pipe (2) near the three-way valve (8).

Images