A centrifugal pump seal flushing water bearing cooling water supply system and control method

Abstract

The present invention discloses a mechanical seal flushing water and bearing cooling water supply system of a centrifugal pump and a control method. The system is mainly aimed at supplying mechanical seal flushing water and bearing lubricating oil cooling water of a centrifugal pump at both ends of the pump in water transported in long-distance, large-diameter and high-lift pipelines in complex terrain. Specifically, a four-way joint is installed from the pump body of the centrifugal pump to connect the pipeline for water diversion, one end of which is installed on the centrifugal pump, and the outlet water is discharged in three directions. A pipe is connected to the upper end of the four-way joint and a ball valve is installed to discharge the air in the pump cavity. The water outlet pipe of the four-way joint is connected to the mechanical seal water supply ports at both ends and the cooling water tanks of the bearings at both ends of the pump. A connecting pipeline is designed at the cooling water tanks of the bearings at both ends of the pump and connected to the pump inlet pipeline. A circulating flushing and cooling system is formed by utilizing the pressure difference between the pump and the bearing lubricating oil cooling water tank and between the pump cavity and the mechanical seal part. The bearing cooling water supply system and the mechanical seal water supply system are also omitted, thereby reducing the construction cost, production cost, and overhaul and maintenance cost.

Description

Technical Field

[0001] The invention relates to a pump seal flushing water and bearing cooling water supply system and a control method, in particular to a centrifugal pump seal flushing water and bearing cooling water supply system and a control method. Background Art

[0002] At present, there are more and more water transfer projects in my country, and more and more centrifugal pumps are used in water transfer systems. Because mechanical seals have the advantages of reliable sealing, long service life, and low friction power consumption, they are widely used in large and medium-sized pipeline water transfer projects in China. In the horizontal split horizontal single-stage or multi-stage centrifugal pumps used, the common centrifugal pump machine sealing water is basically designed and installed with a complete set of complex water supply systems to provide, and the capital and manpower costs invested in the operation and maintenance process are high. The shaft and bearings of the centrifugal pump work in a high temperature, high pressure, and high speed environment. The friction heat generated by the high-speed rotation of the bearings makes the temperature rise of the shaft and bearings much higher than the allowable working temperature rise range. High temperature will cause the lubricating oil to coke, and the sealing ring will have carbon deposition and lose elasticity and other adverse consequences. It is urgent to cool them with shaft and bearing devices with good cooling effect. In the commonly used horizontal split horizontal single-stage or multi-stage centrifugal pumps, the common centrifugal pump machine sealing water is basically designed and installed with a complex water supply system to provide bearing cooling water. Invisibly increase the construction cost, production cost, and overhaul and maintenance cost of the project, and it is not convenient for overall operation control. Summary of the invention

[0003] The purpose of the present invention is to provide a centrifugal pump mechanical seal flushing water bearing cooling water supply system and control method in response to the above-mentioned existing problems, which optimizes and eliminates a set of mechanical seal flushing water and bearing lubricating oil cooling water supply systems, and can provide stable supply of mechanical seal water while providing cooling water for the bearings at both ends of the centrifugal pump. The pressure difference between the pump chamber-bearing lubricating oil cooling water tank-centrifugal pump inlet pipe formed during the operation of the pump body, and the high-pressure area in the pump chamber of the centrifugal pump body (9) when the pump is running, form a circulation working mode of the bearing lubricating oil cooling system and the mechanical seal flushing water system, thereby improving the stable control of the temperature of the bearing lubricating oil and the stable supply of the mechanical seal flushing water. While eliminating a set of bearing cooling water supply systems, a set of mechanical seal water supply systems is also eliminated, reducing construction costs, production costs, and overhaul and maintenance costs.

[0004] The technical solution adopted by the present invention is as follows:

[0005] The purpose of the present invention is to provide a mechanical seal flushing water bearing cooling water supply system and control method for a centrifugal pump in response to the above-mentioned problems, optimize and eliminate the mechanical seal water and bearing lubricating oil cooling water supply system, and provide cooling water for the bearing lubricating oil at both ends of the centrifugal pump while providing a stable supply of mechanical seal flushing water.

[0006] The technical solution adopted by the present invention is as follows:

[0007] The present invention provides a centrifugal pump mechanical seal flushing water bearing cooling water supply system, the centrifugal pump body is connected to a four-way joint, the left end of the four-way joint is connected to the left water supply pipe and the left cooling water pipe in sequence to the left bearing cooling water tank, and the right end of the four-way joint is connected to the right bearing cooling water tank through the right connecting pipe and the right cooling water pipe. The water pressure of the pump cavity during the operation of the pump is higher than the water pressure of the left bearing cooling water tank and the right bearing cooling water tank, forming an automatic water supply system, which can circulate and effectively cool the bearing lubricating oil, improve the service life of the bearing, save a set of independent bearing cooling water supply system, and reduce construction cost, production cost, and overhaul and maintenance cost.

[0008] Furthermore, the left bearing cooling water tank is connected to the left water inlet interface installed on the centrifugal pump inlet pipe through the left return water pipe; the right bearing cooling water tank is connected to the right water inlet interface installed on the centrifugal pump inlet pipe through the right return water pipe. The water pressure of the left bearing cooling water tank and the right bearing cooling water tank during the operation of the pump is higher than the water pressure of the centrifugal pump inlet pipe, so as to form an automatic cooling circulation system. The cooling water of the centrifugal pump is formed into a self-circulating cooling structure by using a simple structural change, which improves the circulation cooling effect while effectively utilizing water resources, and ensures the safe, stable and efficient operation of the centrifugal pump. Furthermore, the left water supply pipe is connected to the left flushing water pipe, which is connected to the left mechanical seal part, so that the four-way joint and the left mechanical seal part are connected; the right connecting pipeline is connected to the right flushing water pipe, which is connected to the right mechanical seal part, so that the four-way joint and the right mechanical seal part are connected. The internal liquid of the mechanical seal formed by the flushing water pipe, the water supply pipe and the mechanical seal part is flushed due to the pressure difference, forming a circulation system, improving the circulation flushing effect, and enabling the mechanical seal to work continuously without leakage. Eliminating a set of independent mechanical seal water supply system reduces construction cost, production cost, and overhaul and maintenance cost.

[0009] Furthermore, a left Y-type filter is installed on the right connecting pipeline, and a right Y-type filter is installed on the left water supply pipe. The beneficial effect is that the water supplied to the mechanical seal part and the bearing cooling water tank can be effectively filtered to remove particles therein, thereby ensuring the stability of the structure and extending the service life.

[0010] Furthermore, a ball valve is installed on the four-way joint. The air in the pump can be discharged through the ball valve before the pump is started, so as to avoid the vacuum pump running idle and causing equipment damage.

[0011] Further, a left observer or monitoring device is installed on the left water return pipe, and an observer or monitoring device is installed on the right water return pipe. The water flow in the water return pipe can be monitored in time through the observer and the monitoring device to find problems in time.

[0012] Furthermore, a left cooling water pipe ball valve is installed on the left cooling water pipe, and a right cooling water pipe ball valve is installed on the right cooling water pipe, so that the temperature of the bearing lubricating oil can be effectively controlled by adjusting the left cooling water pipe ball valve and the right cooling water pipe ball valve to adjust the amount of cooling water passing through the left cooling water pipe and the right cooling water pipe.

[0013] Furthermore, a left flushing water pipe ball valve is installed on the left flushing water pipe, and a right flushing water pipe ball valve is installed on the right flushing water pipe. When the equipment is in an emergency or needs to stop running, the left flushing water pipe ball valve and the left cooling water pipe ball valve are used to cooperate with each other to close the water supply to the left system, and the right manual ball valve and the right cooling water pipe ball valve are used to cooperate with each other to close the water supply to the right system.

[0014] The present invention provides a method for supplying mechanical seal flushing water bearing cooling water to a water supply system using a centrifugal pump.

[0015] Step 1: When the centrifugal pump is in shutdown state, close the left cooling water pipe ball valve, left flushing water pipe ball valve, right cooling water pipe ball valve, right flushing water pipe ball valve and manual ball valve;

[0016] Step 2: Open the inlet valve of the pump group, slowly open the manual ball valve to exhaust air, and close the manual ball valve when water comes out of the manual ball valve;

[0017] Step 3: Open the left cooling water pipe ball valve, the left flushing water pipe ball valve, the right cooling water pipe ball valve, and the right flushing water pipe ball valve until the left cooling water tank, the right cooling water tank, the right return pipe, the left return pipe, the left mechanical seal, and the left mechanical seal are filled with water.

[0018] Furthermore, the temperature of the bearing lubricating oil at both ends of the pump is monitored by the left observer and the observer or by temperature monitoring, and the amount of cooling water passing through the left cooling water pipe and the right cooling water pipe is adjusted by the left cooling water pipe ball valve and the right cooling water pipe ball valve to control the temperature of the bearing lubricating oil at both ends of the pump. Ensure the safe, stable and efficient operation of the equipment

[0019] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0020] 1. It effectively optimizes the process and eliminates the need for an independent mechanical seal water supply system. The liquid forms a circulation system due to the pressure difference and high pressure to low pressure when the pump is running, which improves the circulation flushing effect and enables the mechanical seal to work continuously without leakage. It provides a mechanical seal water supply method for centrifugal pumps, reduces construction and operation and maintenance costs, and saves human resources.

[0021] 2. The process has been further effectively optimized, eliminating a set of independent bearing lubricating oil cooling water supply system. Simple structural changes have been made to form a self-circulating cooling structure for the cooling water of the centrifugal pump. While effectively utilizing water resources, the circulating cooling effect has been improved, the water supply stability of the bearing lubricating oil cooling water has been improved, and operation control has been facilitated, further reducing construction and operation and maintenance costs and saving resources.

[0022] 3. Technology monitors temperature and adjusts according to the temperature. The temperature of the bearing lubricating oil at both ends of the large and small water supply pumps is within the range, ensuring the safe, stable and efficient operation of the system.

[0023] 4. Effectively ensure the safe, stable and efficient operation of the centrifugal pump and improve the delivery capacity of the water delivery and regulation system. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the seal flushing water and bearing cooling water supply system of a pump.

[0025] Markings in the figure: 1 is the coupling, 2 is the drive end bearing, 3 is the left cooling water tank, 4 is the left cooling water pipe, 5 is the manual ball valve, 6 is the left water supply pipe, 7 is the left flushing water pipe ball valve, 8 is the left flushing water pipe, 9 is the centrifugal pump body, 10 is the left Y-type filter, 11 is the four-way joint, 12 is the manual ball valve, 13 is the right Y-type filter, 14 is the right water supply pipe, 15 is the manual ball valve, 16 is the right flushing water pipe ball valve, 17 is the right flushing water pipe, 18 is the right cooling water pipe, 19 is the right drive end bearing, 20 is the right bearing cooling water tank, 21 is the right observer, 22 is the right return pipe, 23 is the right water inlet interface, 24 is the inlet pipe, 25 is the inlet pipe, 26 is the base, 27 is the left water inlet interface, 28 is the left return pipe, 29 is the left observer, 30 is the main shaft, 31 is the left mechanical seal, and 32 is the right mechanical seal. DETAILED DESCRIPTION

[0026] The present invention will be described in detail below in conjunction with the accompanying drawings.

[0027] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0028] like Figure 1As shown, the mechanical seal is located at both ends of the centrifugal pump, and the mechanical seal end cover is located on the centrifugal pump cover and the centrifugal pump body 9. A connecting short pipe is installed from the top of the centrifugal pump body 9, and a four-way joint 11 is installed on the other end of the short pipe. A manual ball valve 12 is installed at the other end of the four-way joint 11, and water flows to the left and right water supply directions through the four-way joint 11. The left end of the four-way joint 11 is connected to the left water supply pipe 6, the T-joint, and the left cooling water pipe 4 in sequence, so that the four-way joint 11 is connected to the left bearing cooling water tank 3. At the same time, a left Y-type filter 10 is installed on the left water supply pipe 6. The mechanical seal water and bearing lubricating oil cooling water on the left side are supplied through the left water supply pipe 6. The other end of the T-joint is connected to the left flushing water pipe 8, and the left flushing water pipe 8 is connected to the left mechanical seal part 31, so that the four-way joint 11 is connected to the left mechanical seal part 31. The left bearing cooling water tank 3 is connected to the left water inlet interface 27 installed on the centrifugal pump inlet pipe 25 through the left return water pipe 28, the left observer 29 or monitoring device is installed on the left return water pipe 28, the left cooling water pipe ball valve 5 is installed on the left cooling water pipe 4, and the left flushing water pipe ball valve 7 is installed on the left flushing water pipe 8.

[0029] When the centrifugal pump body 9 starts running, water flows in from the low-pressure end centrifugal pump inlet pipe 25, and flows out from the pump outlet after being pressurized. At this time, the pump cavity of the centrifugal pump body 9 belongs to the high-pressure area, and the water pressure in the pump cavity is higher than the water pressure in the left bearing cooling water tank 3, and the water pressure in the left bearing cooling water tank 3 is higher than the water pressure in the centrifugal pump inlet pipe 25. Therefore, water enters the left bearing cooling water tank 3 through the four-way joint 11, the left water supply pipe 6, the left Y-type filter 10, the left cooling water pipe ball valve 5, and the left cooling water pipe 4, and then enters the left water inlet interface 27 after passing through the left return water pipe 28, and finally flows in from the 9 pump again, forming a left-side circulating water supply. By utilizing the water pressure difference between the various components formed during the operation of the pump, an automatic water supply system is formed, which can circulate and effectively cool the bearing lubricating oil.

[0030] The right end of the four-way joint 11 is connected to the right connecting pipe (14), the T-joint, and the right cooling water pipe 18 in sequence, so that the four-way joint 11 is connected to the right bearing cooling water tank 20, and the right Y-type filter 13 is installed on the right connecting pipe (14). The mechanical seal water and the bearing lubricating oil cooling water on the right side are supplied through the right connecting pipe (14). The other end of the T-joint is connected to the right flushing water pipe 17, and the right flushing water pipe 17 is connected to the right mechanical seal part 32, so that the four-way joint 11 is connected to the right mechanical seal part 32. The right bearing cooling water tank 20 is connected to the right water inlet interface 23 installed on the centrifugal pump inlet pipe 25 through the right return water pipe 22, and the right observer 21 or monitoring device is installed on the right return water pipe 22. The right cooling water pipe ball valve 15 is installed on the right cooling water pipe 18, and the right flushing water pipe ball valve 16 is installed on the right flushing water pipe 17.

[0031] When the centrifugal pump body 9 starts running, the pump cavity of the centrifugal pump body 9 is in a high-pressure area, and the water pressure in the pump cavity is higher than the water pressure in the right bearing cooling water tank 20, and the water pressure in the right bearing cooling water tank 20 is higher than the water pressure in the centrifugal pump inlet pipe 25. Therefore, water enters the right bearing cooling water tank through the four-way joint 11, the right connecting pipe (14), the right Y-type filter 13, the right cooling water pipe ball valve 15, and the right cooling water pipe 18, and then enters the right water inlet interface 23 after passing through the right return pipe 22, and finally flows in from the inlet pipe 25 of the 9 pump again, forming a right-side circulating water supply. By utilizing the water pressure difference between the various components formed during the operation of the pump, an automatic water supply system is formed, which can circulate and effectively cool the bearing lubricating oil.

[0032] The method and principle of the mechanical seal flushing water bearing cooling water supply system using a centrifugal pump of the present invention are as follows:

[0033] Step 1: When the centrifugal pump is in the shutdown state, close the left cooling water pipe ball valve 5, the left flushing water pipe ball valve 7, the right cooling water pipe ball valve 15, the right flushing water pipe ball valve 16 and the manual ball valve 12.

[0034] Step 2: Open the inlet valve of the pump group, slowly open the manual ball valve 12 to exhaust air, and close the manual ball valve 12 when water flows out of the manual ball valve 12.

[0035] Step 3: Open the left cooling water pipe ball valve 5, the left flushing water pipe ball valve 7, the right cooling water pipe ball valve 15, and the right flushing water pipe ball valve 16 until the left bearing cooling water tank 3, the right bearing cooling water tank 20, the right return water pipe 22, the left return water pipe 28, the left mechanical seal part 31, and the right mechanical seal part 32 are filled with water, then open the manual ball valve (12) to exhaust again. When the air in the centrifugal pump body 9 is completely exhausted and the water is discharged, close the manual ball valve (12). At this time, all the air in the pump chamber has been exhausted and the pump is ready to start.

[0036] Step 4: Monitor the temperature of the bearing lubricating oil at both ends of the centrifugal pump body 9 by observing or temperature monitoring with the left observer 29 and the right observer 21, and adjust the amount of cooling water passing through the left cooling water pipe 4 and the right cooling water pipe 18 by the left cooling water pipe ball valve 5 and the right cooling water pipe ball valve 15 to control the temperature of the bearing lubricating oil at both ends of the centrifugal pump body 9. Ensure the safe, stable and efficient operation of the equipment.

[0037] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A control method for a centrifugal pump seal flushing water bearing cooling water supply system, characterized in that: The centrifugal pump seal flushing water bearing cooling water supply system comprises a centrifugal pump body (9), the centrifugal pump body (9) is connected to a four-way joint (11), the left end of the four-way joint (11) is connected to a left water supply pipe (6) and a left cooling water pipe (4) in sequence to a left bearing cooling water tank (3), and the right end of the four-way joint (11) is connected to a right bearing cooling water tank (20) through a right connecting pipe (14) and a right cooling water pipe (18); the left bearing cooling water tank (3) is connected to a left water inlet interface (20) installed on an inlet pipe (25) of the centrifugal pump through a left return pipe (28). 7) connection; the right bearing cooling water tank (20) is connected to the right water inlet interface (23) installed on the centrifugal pump inlet pipe (25) through the right return pipe (22); the left water supply pipe (6) is connected to the left flushing water pipe (8), the left flushing water pipe (8) is connected to the left mechanical seal part (31), so that the four-way joint (11) and the left mechanical seal part (31) are connected; the right connecting pipe (14) is connected to the right flushing water pipe (17), the right flushing water pipe (17) is connected to the right mechanical seal part (32), so that the four-way joint (11) and the right mechanical seal part (32) are connected; Install a left cooling water pipe ball valve (5) on the left cooling water pipe (4), and install a right cooling water pipe ball valve (15) on the right cooling water pipe (18); A left flushing water pipe ball valve (7) is installed on the left flushing water pipe (8), and a right flushing water pipe ball valve (16) is installed on the right flushing water pipe (17); A manual ball valve (12) is installed on the four-way joint (11); A left observer (29) or a monitoring device is installed on the left water return pipe (28), and a right observer (21) or a monitoring device is installed on the right water return pipe (22); Control methods include: Step 1: When the centrifugal pump is in a shutdown state, close the left cooling water pipe ball valve (5), the left flushing water pipe ball valve (7), the right cooling water pipe ball valve (15), the right flushing water pipe ball valve (16) and the manual ball valve (12); Step 2: Before the pump is running, open the pump unit inlet valve, slowly open the manual ball valve (12) to exhaust air, and close the manual ball valve (12) when water flows out of the manual ball valve (12); Step 3: Open the left cooling water pipe ball valve (5), the left flushing water pipe ball valve (7), the right cooling water pipe ball valve (15), and the right flushing water pipe ball valve (16) until the left bearing cooling water tank (3), the right bearing cooling water tank (20), the right return water pipe (22), the left return water pipe (28), the left mechanical seal part (31), and the right mechanical seal part (32) are filled with water, open the manual ball valve (12), and exhaust again. When the air in the centrifugal pump body (9) is completely exhausted and the water is discharged, close the manual ball valve (12).

2. The control method of the centrifugal pump seal flushing water bearing cooling water supply system according to claim 1 is characterized in that: The temperature of the bearing lubricating oil at both ends of the centrifugal pump body (9) is monitored by means of observation or temperature monitoring using a left observer (29) and a right observer (21), and the amount of cooling water passing through the left cooling water pipe (4) and the right cooling water pipe (18) is adjusted by means of a left cooling water pipe ball valve (5) and a right cooling water pipe ball valve (15) to control the temperature of the bearing lubricating oil at both ends of the centrifugal pump body (9).

3. The control method of the centrifugal pump seal flushing water bearing cooling water supply system according to claim 1, characterized in that: A right Y-type filter (13) is installed on the right connecting pipe (14), and a left Y-type filter (10) is installed on the left water supply pipe (6).

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