阅读说明：本技术 大型立式轴流泵同步电机主轴轴承油冷系统及油冷方法 (Oil cooling system and oil cooling method for main shaft bearing of large vertical axial-flow pump synchronous motor ) 是由 李典基 顾建利 朱吉生 李庆义 董庆杰 崔彦平 许金民 杨世明 丁莹莹 姚辉勇 于 2020-07-09 设计创作，主要内容包括：大型立式轴流泵同步电机主轴轴承油冷系统及油冷方法,包括：电机,所述电机内设有定子和转子,转子与动力轴连接,动力轴通过推力轴承和导轴承进行支撑,推力轴承和导轴承外侧分别设有油腔,油腔内有冷却油,油腔内设有温度传感器和油位传感器；冷油机,所述冷油机通过循环管路分别与推力轴承油腔和导轴承油腔相连,推力轴承油腔和导轴承油腔内热的冷却油通过管道流到冷油机内,在冷油机内和冷媒进行热交换,冷却后的冷却油再回流到油腔内对推力轴承和导轴承进行冷却。设备占用厂房空间减少,故障率低,维护更加简单,热传导效率高,冷却效果更好,使用寿命延长。(A large vertical axial-flow pump synchronous motor spindle bearing oil cooling system and an oil cooling method comprise the following steps: the cooling oil cooling device comprises a motor, wherein a stator and a rotor are arranged in the motor, the rotor is connected with a power shaft, the power shaft is supported by a thrust bearing and a guide bearing, oil cavities are respectively arranged on the outer sides of the thrust bearing and the guide bearing, cooling oil is arranged in the oil cavities, and a temperature sensor and an oil level sensor are arranged in the oil cavities; and the cooling oil machine is respectively connected with the thrust bearing oil cavity and the guide bearing oil cavity through a circulating pipeline, cooling oil in the thrust bearing oil cavity and the guide bearing oil cavity flows into the cooling oil machine through pipelines, the cooling oil exchanges heat with a refrigerant in the cooling oil machine, and the cooled cooling oil flows back into the oil cavity to cool the thrust bearing and the guide bearing. The equipment occupies less workshop space, has low failure rate, is simpler to maintain, has high heat conduction efficiency, better cooling effect and prolonged service life.)

1. Large-scale vertical axial-flow pump synchronous machine main shaft bearing oil cooling system, its characterized in that: the method comprises the following steps:

the cooling oil cooling device comprises a motor, wherein a stator and a rotor are arranged in the motor, the rotor is connected with a power shaft, the power shaft is supported by a thrust bearing and a guide bearing, oil cavities are respectively arranged on the outer sides of the thrust bearing and the guide bearing, cooling oil is arranged in the oil cavities, and a temperature sensor and an oil level sensor are arranged in the oil cavities;

and the cooling oil machine is respectively connected with the thrust bearing oil cavity and the guide bearing oil cavity through a circulating pipeline, cooling oil in the thrust bearing oil cavity and the guide bearing oil cavity flows into the cooling oil machine through pipelines, the cooling oil exchanges heat with a refrigerant in the cooling oil machine, and the cooled cooling oil flows back into the oil cavity to cool the thrust bearing and the guide bearing.

2. The large-scale vertical axial-flow pump synchronous motor spindle bearing oil cooling system according to claim 1, characterized in that: the circulating pipeline comprises an oil supply main pipe connected with an oil outlet of the cold oil engine and an oil return main pipe connected with an oil return port of the cold oil engine, the oil supply main pipe is respectively connected with a first oil supply pipe and a second oil supply pipe, the oil return main pipe is respectively connected with a first oil return pipe and a second oil return pipe, the first oil supply pipe and the first oil return pipe are respectively connected with an inlet and an outlet of the thrust bearing oil cavity, and the second oil supply pipe and the second oil return pipe are respectively connected with an inlet and an outlet of the guide bearing oil cavity.

3. The large-scale vertical axial-flow pump synchronous motor spindle bearing oil cooling system according to claim 1, characterized in that: the inlet and the outlet of the thrust bearing oil cavity are arranged on one side of the bottom, and the inlet and the outlet of the guide bearing oil cavity are arranged on the bottom.

4. The large-scale vertical axial-flow pump synchronous motor spindle bearing oil cooling system according to claim 3, characterized in that: the oil cavity of the thrust bearing and the oil cavity of the guide bearing are both provided with a dispersion structure, and the dispersion structures are used for uniformly dispersing cooling oil so that the cooling oil can fully exchange heat with the thrust bearing and the guide bearing.

5. The large-scale vertical axial-flow pump synchronous motor spindle bearing oil cooling system according to claim 4, characterized in that: the dispersing structure comprises an annular sleeve horizontally arranged at the bottom in the oil cavity and connected with the inlet, a plurality of oil guide pipes which are vertically upward are arranged on the annular sleeve along the circumference, the top ends of the oil guide pipes extend to the top of the oil cavity, and cooling oil is sequentially discharged from the outlet from bottom to top.

6. The large-scale vertical axial-flow pump synchronous motor spindle bearing oil cooling system according to claim 2, characterized in that: the oil level sensor is characterized in that a first oil supply pump is arranged on the first oil supply pipe, a second oil supply pump is arranged on the second oil supply pipe, a first oil return pump is arranged on the first oil return pipe, a second oil return pump is arranged on the second oil return pipe, and the first oil supply pump, the second oil supply pump, the first oil return pump, the second oil return pump, the temperature sensor and the oil level sensor are respectively connected with the PLC control system.

7. The large-scale vertical axial-flow pump synchronous motor spindle bearing oil cooling system according to claim 2, characterized in that: and the oil return main pipe is provided with a filter.

8. The method for cooling the main shaft bearing oil of the large vertical axial-flow pump synchronous motor is characterized by comprising the following steps: the cooling oil heated in the thrust bearing and guide bearing oil cavities of the motor flows into an external oil cooler through pipelines, the oil cooler exchanges heat with a refrigerant, and the cooled cooling oil flows back into the oil cavities to cool the thrust bearing and the guide bearing.

9. The oil cooling method for the main shaft bearing of the large vertical axial-flow pump synchronous motor according to claim 8, characterized in that: the cooling oil output from the oil cooler enters the oil cavity, and is uniformly dispersed through the dispersing structure, so that the cooling oil fully exchanges heat with the thrust bearing and the guide bearing.

10. The oil cooling method for the main shaft bearing of the large vertical axial-flow pump synchronous motor according to claim 8, characterized in that: and a set of circulating pipelines are respectively arranged between the oil cooling machine and the thrust bearing oil cavity and between the oil cooling machine and the guide bearing oil cavity, an oil supply pump and an oil return pump are respectively arranged on the two sets of circulating pipelines, and the flow of cooling oil in the thrust bearing oil cavity and the guide bearing oil cavity is independently controlled, so that the temperatures of the thrust bearing and the guide bearing are in the same level.

The technical field is as follows:

the invention relates to the technical field of cooling of bearings of synchronous motors of large axial-flow pumps, in particular to an oil cooling system and an oil cooling method for main shaft bearings of synchronous motors of large vertical axial-flow pumps.

Background art:

the main motor of the axial-flow pump water pump unit of the large-scale pump station is a synchronous motor, and a thrust bearing and a guide bearing can generate a large amount of heat during operation and must be cooled in time. The cooling of the main unit at present adopts a technical water supply direct cooling mode, and the following problems mainly exist: the technical water supply system directly takes water from the lake, although the water filter is arranged for filtering, the water filter can only filter impurities larger than a filter screen of the water filter, and can not solve all the impurities, particularly moss, suspended sediment and the like. The abrasion and scale of water pump and technical water supply system equipment are aggravated due to the influence of water hardness, aquatic organisms, pH value and the like, and the service life of the system equipment such as a water pump, a valve, an oil cooler, a pipeline and the like is shortened. The cooler in the unit is worn all year round by adopting a small-caliber copper pipe, and the cooler copper pipe can be seriously guided to be perforated, so that the running safety of the unit is seriously influenced. The water supply and cooling water system of the technology has high failure rate and affects the safe production.

A technology which is reliable compared with the prior technical water supply scheme, namely a circulating cooling water system, is adopted in the industry. The system is a closed circulation, cooling water passes through a pipeline booster pump in a pipeline, after power is increased, the cooling water enters a bearing bush cooler for refrigeration, then flows into a main unit cooler through a water outlet pipeline, carries out heat exchange in the cooler, takes away heat generated by the operation of the main unit in the main unit cooler, and flows back through a pipeline water return pipe and then passes through a filter, the pipeline booster pump and the bearing bush cooler, so that the cooling of the main unit is realized. The system can set the return water temperature of the pipeline, and when the return water temperature is not higher than the set temperature, the compressor of the bearing bush cooler does not work, so that the energy-saving effect is achieved. The technology is only improved in the aspect of cooling water quality, has a complex structure, needs to newly build a pump room of a cooling unit and the like, has large investment, and also has the problems of reliability, complex maintenance and the like. The cooling principle of the technology is not changed, heat is conducted to cooling oil through the bearing, then conducted to a cooling water system through the cooling oil, and taken away through the cooling water system, and the indirect heat conduction mode is low in heat conduction efficiency and invisibly increases more energy loss.

Among the current cooling methods, cool off thrust bearing and guide bearing simultaneously by one set of cooling water system, the cooling water of the same flow cools off through thrust bearing and guide bearing respectively, but because the operational environment in thrust bearing and the guide bearing oil chamber, the friction atress, the space, differences such as size, the different condition of thrust bearing and guide bearing temperature appears very easily, thereby the coefficient of thermal expansion that leads to thrust bearing and guide bearing takes place the difference, inner structure's stress changes, thrust bearing and guide bearing can appear slightly asynchronous when the power shaft is rotatory, the card is pause, the condition such as extra atress, the damage of thrust bearing and guide bearing can be accelerated to the time of having a specified duration, and the service life is shortened.

Therefore, the development of an advanced, efficient, safe and reliable cooling technology for the large-scale axial-flow pump synchronous motor bearing becomes a technical problem to be solved urgently in the industry.

The invention content is as follows:

in order to make up for the defects of the prior art, the invention provides an oil cooling system and an oil cooling method for a main shaft bearing of a synchronous motor of a large vertical axial-flow pump, solves the problems of high failure rate and multiple accidents caused by the prior water cooler technology, and solves the problems of low indirect heat conduction and low heat conduction efficiency of the prior water cooler technology.

The technical scheme adopted by the invention for solving the technical problems is as follows:

large-scale vertical axial-flow pump synchronous machine main shaft bearing oil cooling system includes:

the cooling oil cooling device comprises a motor, wherein a stator and a rotor are arranged in the motor, the rotor is connected with a power shaft, the power shaft is supported by a thrust bearing and a guide bearing, oil cavities are respectively arranged on the outer sides of the thrust bearing and the guide bearing, cooling oil is arranged in the oil cavities, and a temperature sensor and an oil level sensor are arranged in the oil cavities;

and the cooling oil machine is respectively connected with the thrust bearing oil cavity and the guide bearing oil cavity through a circulating pipeline, cooling oil in the thrust bearing oil cavity and the guide bearing oil cavity flows into the cooling oil machine through pipelines, the cooling oil exchanges heat with a refrigerant in the cooling oil machine, and the cooled cooling oil flows back into the oil cavity to cool the thrust bearing and the guide bearing.

The circulating pipeline comprises an oil supply main pipe connected with an oil outlet of the cold oil engine and an oil return main pipe connected with an oil return port of the cold oil engine, the oil supply main pipe is respectively connected with a first oil supply pipe and a second oil supply pipe, the oil return main pipe is respectively connected with a first oil return pipe and a second oil return pipe, the first oil supply pipe and the first oil return pipe are respectively connected with an inlet and an outlet of the thrust bearing oil cavity, and the second oil supply pipe and the second oil return pipe are respectively connected with an inlet and an outlet of the guide bearing oil cavity.

The inlet and the outlet of the thrust bearing oil cavity are arranged on one side of the bottom, and the inlet and the outlet of the guide bearing oil cavity are arranged on the bottom.

The oil cavity of the thrust bearing and the oil cavity of the guide bearing are both provided with a dispersion structure, and the dispersion structures are used for uniformly dispersing cooling oil so that the cooling oil can fully exchange heat with the thrust bearing and the guide bearing.

The dispersing structure comprises an annular sleeve horizontally arranged at the bottom in the oil cavity and connected with the inlet, a plurality of oil guide pipes which are vertically upward are arranged on the annular sleeve along the circumference, the top ends of the oil guide pipes extend to the top of the oil cavity, and cooling oil is sequentially discharged from the outlet from bottom to top.

The oil level sensor is characterized in that a first oil supply pump is arranged on the first oil supply pipe, a second oil supply pump is arranged on the second oil supply pipe, a first oil return pump is arranged on the first oil return pipe, a second oil return pump is arranged on the second oil return pipe, and the first oil supply pump, the second oil supply pump, the first oil return pump, the second oil return pump, the temperature sensor and the oil level sensor are respectively connected with the PLC control system.

And the oil return main pipe is provided with a filter.

The method for cooling the main shaft bearing oil of the large vertical axial-flow pump synchronous motor comprises the steps of enabling cooling oil heated in oil cavities of a thrust bearing and a guide bearing of the motor to flow into an external oil cooler through pipelines, carrying out heat exchange with a refrigerant in the oil cooler, and enabling the cooled cooling oil to flow back into an oil cavity to cool the thrust bearing and the guide bearing.

The cooling oil output from the oil cooler enters the oil cavity, and is uniformly dispersed through the dispersing structure, so that the cooling oil fully exchanges heat with the thrust bearing and the guide bearing.

And a set of circulating pipelines are respectively arranged between the oil cooling machine and the thrust bearing oil cavity and between the oil cooling machine and the guide bearing oil cavity, an oil supply pump and an oil return pump are respectively arranged on the two sets of circulating pipelines, and the flow of cooling oil in the thrust bearing oil cavity and the guide bearing oil cavity is independently controlled, so that the temperatures of the thrust bearing and the guide bearing are in the same level.

By adopting the scheme, the invention has the following advantages:

(1) the traditional complex water cooler system is cancelled, the investment is reduced by one third, the occupied plant space of equipment is reduced, the failure rate is low, and the maintenance is simpler;

(2) cooling oil in the oil cavities of the thrust bearing and the guide bearing flows into an external oil cooler through pipelines, heat exchange is carried out between the cooling oil and a refrigerant in the oil cooler, and the cooled cooling oil flows back into the oil cavity to cool the thrust bearing and the guide bearing, so that the heat conduction efficiency is high, and the cooling effect is better;

(3) in view of the special annular inner cavity structures in the oil cavities of the thrust bearing and the guide bearing, in order to avoid that cooling oil is directly discharged from an outlet after entering the oil cavities, a dispersing structure is specially designed in the oil cavities, so that the cooling oil entering the oil cavities can be uniformly dispersed, the cooling time of the cooling oil in the oil cavities can be prolonged, the cooling oil can be subjected to energy conversion in the oil cavities, the thrust bearing and the guide bearing are cooled, and the cooling efficiency is greatly improved;

(4) the flow of cooling oil in the oil cavities of the thrust bearing and the guide bearing can be independently controlled, the temperatures of the thrust bearing and the guide bearing are basically in the same level, the difference of the thermal expansion coefficients of the thrust bearing and the guide bearing and the change of the stress of the internal structure are avoided, and the service life of the thrust bearing and the guide bearing is prolonged.

Description of the drawings:

FIG. 1 is a schematic structural diagram of the present invention.

Fig. 2 is an enlarged schematic structural view of the motor of fig. 1.

FIG. 3 is a schematic top view of a dispersion structure according to the present invention.

In the figure, 1, a motor, 2, a stator, 3, a rotor, 4, a power shaft, 5, a thrust bearing, 6, a guide bearing, 7, a water pump impeller, 8, an oil chamber, 9, a temperature sensor, 10, an oil level sensor, 11, a cold oil machine, 12, an oil supply main pipe, 13, an oil return main pipe, 14, a first oil supply pipe, 15, a second oil supply pipe, 16, a first oil return pipe, 17, a second oil return pipe, 18, an annular sleeve, 19, an oil guide pipe, 20, a first oil supply pump, 21, a second oil supply pump, 22, a first oil return pump, 23, a second oil return pump, 24 and a filter.

The specific implementation mode is as follows:

in order to clearly explain the technical features of the present invention, the following detailed description of the present invention is provided with reference to the accompanying drawings.

As shown in fig. 1 to 3, the oil cooling system for the main shaft bearing of the large vertical axial-flow pump synchronous motor comprises:

the water pump comprises a motor 1, wherein a stator 2 and a rotor 3 are arranged in the motor 1, the rotor 3 is connected with a power shaft 4, the power shaft 4 drives a water pump impeller 7 to rotate to provide power for water conveying, the power shaft 4 is supported by a thrust bearing 5 and a guide bearing 6, oil cavities 8 are respectively arranged on the outer sides of the thrust bearing 5 and the guide bearing 6, cooling oil is arranged in the oil cavities 8, and a temperature sensor 9 and an oil level sensor 10 are arranged in the oil cavities 8;

the oil cooler 11 is connected with the oil cavity of the thrust bearing 5 and the oil cavity of the guide bearing 6 through a circulating pipeline, cooling oil in the oil cavity of the thrust bearing 5 and the oil cavity of the guide bearing 6 flows into the oil cooler 11 through pipelines, heat exchange is carried out between the cooling oil 11 and a refrigerant, the cooled cooling oil flows back into the oil cavity 8 to cool the thrust bearing 5 and the guide bearing 6, heat conduction efficiency is high, and cooling effect is better.

The circulating pipeline comprises a main oil supply pipe 12 connected with an oil outlet of the oil cooler 11 and a main oil return pipe 13 connected with an oil return port of the oil cooler 11, the main oil supply pipe 12 is respectively connected with a first oil supply pipe 14 and a second oil supply pipe 15, the main oil return pipe 13 is respectively connected with a first oil return pipe 16 and a second oil return pipe 17, the first oil supply pipe 14 and the first oil return pipe 16 are respectively connected with an inlet and an outlet of an oil cavity of the thrust bearing 5, and the second oil supply pipe 15 and the second oil return pipe 17 are respectively connected with an inlet and an outlet of an oil cavity of the guide bearing 6. A branch of cooling oil from the oil cooler 11 enters an oil cavity of the thrust bearing 5 through an oil supply main pipe 12 and a first oil supply pipe 14, cools the thrust bearing 5 in the oil cavity of the thrust bearing 5, and then returns to the oil cooler 11 through a first oil return pipe 16 and an oil return main pipe 13; the other branch enters the oil cavity of the guide bearing 6 through the oil supply main pipe 12 and the second oil supply pipe 15, cools the guide bearing 6 in the oil cavity of the guide bearing 6, returns to the oil cooler 11 through the second oil return pipe 17 and the oil return main pipe 13, exchanges heat with the refrigerant in the oil cooler 11, and circulates in the way.

The inlet and the outlet of the oil cavity of the thrust bearing 5 are arranged at one side of the bottom, and the inlet and the outlet of the oil cavity of the guide bearing 6 are arranged at the bottom. The oil cavity of the thrust bearing 5 and the oil cavity of the guide bearing 6 are respectively provided with a dispersion structure, and the dispersion structures are used for uniformly dispersing cooling oil so that the cooling oil can fully exchange heat with the thrust bearing 5 and the guide bearing 6. The dispersing structure comprises an annular sleeve 18 which is horizontally arranged at the bottom in the oil cavity 8 and is connected with an inlet, a plurality of oil guide pipes 19 which are vertically upward are arranged on the annular sleeve 18 along the circumference, the top ends of the oil guide pipes 19 extend to the top of the oil cavity 8, and cooling oil is discharged from an outlet from bottom to top in sequence. The top of the oil cavity of the thrust bearing 5 is provided with a detachable protective cover, the dispersing structure is hoisted from the upper part and placed in the oil cavity of the thrust bearing 5, and the bottom of the oil cavity of the thrust bearing 5 supports the dispersing structure; the bottom of the oil cavity of the guide bearing 6 is provided with a detachable protective cover, the dispersing structure is placed into the oil cavity of the guide bearing 6 from the lower part, and the bottom of the oil cavity of the guide bearing 6 supports the dispersing structure; the dispersing structure can be made of oil corrosion resistant light material. The cooling oil enters the oil cavity 8 from the bottom inlet, firstly enters the annular sleeve 18 with the dispersion structure, then enters the plurality of oil guide pipes 19, the oil guide pipes 19 disperse the cooling oil, the time of the cooling oil in the oil cavity 8 can be prolonged, the cooling oil enters the oil cavity 8 from bottom to top through the plurality of oil guide pipes 19, after the thrust bearing 5 and the guide bearing 6 are cooled in the oil cavity 8, the cooling oil is discharged from the bottom outlet in the sequence from bottom to top, and the cooling efficiency is improved.

The oil cooling device is characterized in that a first oil supply pump 20 is arranged on the first oil supply pipe 14 and provides power for cooling oil to enter an oil cavity of the thrust bearing 5, a second oil supply pump 21 is arranged on the second oil supply pipe 15 and provides power for cooling oil to enter an oil cavity of the guide bearing 6, a first oil return pump 22 is arranged on the first oil return pipe 16 and provides power for cooling oil to flow back to the oil cooling machine 11 from the oil cavity of the thrust bearing 5, a second oil return pump 23 is arranged on the second oil return pipe 17 and provides power for cooling oil to flow back to the oil cooling machine 11 from the oil cavity of the guide bearing 6, and the first oil supply pump 20, the second oil supply pump 21, the first oil return pump 22, the second oil return pump 23, the temperature sensor 9 and the oil level sensor 10 are respectively connected with. The temperature sensor 9 can detect the temperature in the oil cavity of the thrust bearing 5 and the oil cavity of the guide bearing 6 in real time and send signals to the PLC control system, when the temperature in the oil cavity of the thrust bearing 5 is higher than the temperature in the oil cavity of the guide bearing 6, the PLC control system controls the working frequency of the first oil supply pump 20 and the first oil return pump 22 to be increased, so that the flow of cooling oil in the oil cavity of the thrust bearing 5 is accelerated, and the temperature in the oil cavity of the thrust bearing 5 is reduced by accelerating heat exchange; on the contrary, when the temperature in the oil cavity of the thrust bearing 5 is lower than the temperature in the oil cavity of the guide bearing 6, the PLC control system controls the working frequency of the second oil supply pump 21 and the second oil return pump 23 to increase the flow rate of the cooling oil in the oil cavity of the guide bearing 6, and increases the heat exchange to reduce the temperature in the oil cavity of the guide bearing 6, so as to ensure that the temperatures of the thrust bearing 5 and the guide bearing 6 are basically at the same level, avoid the difference of the thermal expansion coefficients and the change of the stress of the internal structure, and prolong the service life of the guide bearing. The oil level sensor 10 can detect the oil levels in the oil cavities of the thrust bearing 5 and the guide bearing 6 in real time, and the oil quantity in the oil cavities of the thrust bearing 5 and the guide bearing 6 is stable.

The oil return main pipe 12 is provided with a filter 24, and the filter 24 can filter impurities in the cooling oil.

The method for cooling the spindle bearing oil of the large vertical axial-flow pump synchronous motor comprises the steps of enabling cooling oil heated in oil cavities of a thrust bearing 5 and a guide bearing 6 of a motor 1 to flow into an external oil cooling machine 11 through pipelines, carrying out heat exchange with a refrigerant in the oil cooling machine 11, and enabling the cooled cooling oil to flow back into an oil cavity 8 to cool the thrust bearing 5 and the guide bearing 6.

The cooling oil output from the oil cooler 11 enters the oil cavity 8, and is uniformly dispersed through the dispersing structure, so that the cooling oil fully exchanges heat with the thrust bearing 5 and the guide bearing 6.

And a set of circulating pipelines are respectively arranged between the oil cooling machine 11 and the oil cavity of the thrust bearing 5 and the oil cavity of the guide bearing 6, an oil supply pump and an oil return pump are respectively arranged on the two sets of circulating pipelines, and the flow of cooling oil in the oil cavity of the thrust bearing 5 and the oil cavity of the guide bearing 6 is independently controlled, so that the temperatures of the thrust bearing 5 and the guide bearing 6 are in the same level.

The above-described embodiments should not be construed as limiting the scope of the invention, and any alternative modifications or alterations to the embodiments of the present invention will be apparent to those skilled in the art.

The present invention is not described in detail, but is known to those skilled in the art.