A fluid static pressure main pump mechanical seal test device

Abstract

The present invention relates to the technical field of mechanical seal test devices, and in particular to a fluid static pressure type main pump mechanical seal test device, comprising a base, a motor, a main shaft and a test sleeve, on which a lower cavity, an upper cavity and a top seat are fixed in sequence from bottom to top, the lower end of the main shaft is rotatably mounted on the base, and the upper end is rotatably mounted on the top seat, the motor is connected to the main shaft by transmission, a test sleeve is fixedly mounted on the main shaft, and seal No. 2 and seal No. 3 are sequentially mounted on the test sleeve from bottom to top. The present invention can simulate the actual working conditions of a nuclear main pump and can accurately test the mechanical seal performance of the main pump to be installed; the transmission system is placed at the bottom and the motor is placed at the side, which is more secure, and installation, disassembly, operation and maintenance are more convenient and quick; a balanced seal is set to extend the life of the bearing, the maintenance cycle and service life of the test bench; the No. 1, 2 and 3 seals can be tested as a set, and the No. 2 and 3 seal components can also be tested separately, which has a wider range of applications.

Description

Technical Field

[0001] The invention relates to the technical field of mechanical seal test devices, in particular to a fluid static pressure type main pump mechanical seal test device. Background Art

[0002] In nuclear power plant equipment, the sealing performance of the main pump is particularly important. The mechanical seal of the main pump is an important component of the main pump, which is directly related to whether the main pump can operate normally. Before installing the mechanical seal in the main pump, it is necessary to test the mechanical seal to verify whether the sealing performance of the main pump is qualified, so as to prevent abnormal conditions when the mechanical seal is installed in the main pump and officially operated, causing unplanned shutdown. In addition, during the test run, it is required to simulate the actual working conditions in the main pump to ensure that the test results are accurate and the performance meets the operating requirements. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a fluid static pressure type main pump mechanical seal test device.

[0004] The purpose of the present invention is achieved through the following technical solutions:

[0005] A fluid static pressure type main pump mechanical seal test device, comprising a base, a motor, a main shaft and a test sleeve, wherein a lower cavity, an upper cavity and a top seat are fixed on the base in sequence from bottom to top, the lower end of the main shaft is rotatably mounted on the base, and the upper end is rotatably mounted on the top seat, the motor is transmission-connected to the main shaft, a test sleeve is fixedly mounted on the main shaft, and a No. 1 seal, a No. 2 seal and a No. 3 seal are sequentially mounted on the test sleeve from bottom to top, the No. 1 seal is located inside the lower cavity, the No. 2 seal is located inside the upper cavity, and the No. 3 seal is located between the upper cavity and the top seat; the sealing shell of the top seat A No. 3 sealed water injection flange interface is provided on the side wall of the body, which is connected to the No. 3 sealed water injection pipe of the test system; a No. 2 sealed leakage water flange interface and a No. 3 sealed leakage water flange interface are provided on the side wall of the sealed shell of the top seat, the No. 2 sealed leakage water flange interface is connected to the No. 2 sealed leakage water pipe of the test system, and the No. 3 sealed leakage water flange interface is connected to the No. 3 sealed leakage water pipe of the test system; a temperature sensor is installed on the side wall of the upper cavity, and the induction head of the temperature sensor is located on the inner side of the lower cavity; a No. 1 sealed leakage water interface is provided on the side wall of the upper cavity, which is connected to the No. 1 sealed leakage water pipe of the test system.

[0006] Furthermore, a No. 1 sealed water injection hole and a No. 1 sealed pressure sensor installation hole are opened on the side wall of the lower cavity, and the No. 1 sealed water injection hole and the No. 1 sealed pressure sensor installation hole are arranged opposite to each other.

[0007] Furthermore, a liner seal dynamic ring assembly is installed at the lower end of the test sleeve, a liner seal static ring assembly is installed on the base, a liner seal leakage end mechanical seal is also arranged between the main shaft and the base, and a liner seal leakage hole is also opened on the base.

[0008] Furthermore, the lower end of the main shaft is installed in the base through a lower bearing assembly, and the upper end of the main shaft is installed on the top seat through an upper bearing assembly.

[0009] Furthermore, the base is fixed on the machine base, the motor is installed on the machine base, and the motor is connected to the main shaft through a transmission member.

[0010] Furthermore, the transmission member is a belt, an output pulley is installed at the output end of the motor, an input pulley is installed at the lower end of the main shaft, and the output pulley is connected to the input pulley through a belt transmission.

[0011] Furthermore, the lower end of the test sleeve abuts against the shoulder of the main shaft, and the upper end of the test sleeve is fixed to the main shaft through a positioning assembly, and the positioning assembly includes a petal ring, a pressure ring, a clamping screw and an elastic gasket. The petal ring is clamped on the main shaft, and an annular step is provided on the upper end surface of the test sleeve, and the annular step is coaxial with the main shaft. The pressure ring is installed in the annular step, and the clamping screw passes through the petal ring and is locked in the pressure ring. An elastic gasket is provided between the pressure ring and the annular step.

[0012] Furthermore, a transmission ring is fixedly mounted on the upper end of the test sleeve, a sealing sleeve is fixed below the transmission ring, the sealing sleeve is sleeved on the outer side of the test sleeve, and the No. 2 seal and the No. 3 seal are mounted on the outer side of the sealing sleeve.

[0013] Furthermore, a tensioning assembly for adjusting the position of the motor is also installed on the machine base.

[0014] Furthermore, the tensioning assembly includes a fixed block and an adjusting screw, the fixed block is fixed on the machine base, the adjusting screw is threadably connected to the fixed block, and the front end surface of the adjusting screw abuts against the mounting base of the motor.

[0015] The present invention has the following advantages:

[0016] 1. It can simulate the actual working condition of the nuclear main pump and accurately test the mechanical seal performance of the main pump to be installed. Before the main pump mechanical seal is repaired at the factory or in the power station, it should be installed in the test device for trial operation to verify whether its sealing performance meets the requirements, provide reference and guarantee for online operation, and avoid the mechanical seal being installed on the nuclear main pump and running. The performance does not meet the requirements, resulting in unplanned shutdown and losses.

[0017] 2. The transmission system of the present invention is placed at the bottom and the drive device (motor) is placed at the side. Compared with the existing main pump shaft seal test bench with the motor and transmission device placed on top, the height of the test bench is greatly reduced, the safety is higher, and the installation, disassembly, operation and maintenance are more convenient and quick.

[0018] 3. This test device is equipped with a balanced seal. Through the accurate design of the balanced seal, the axial force of the rotor (spindle) can be effectively balanced, the axial load of the bearing can be reduced, and the life of the bearing, the maintenance cycle and service life of the test bench can be extended.

[0019] 4. This test device can realize the complete set test of No. 1, 2, and 3 seals, and can also realize the separate test of No. 2 and 3 seal components, without the need to build a separate test bench for the separate test of No. 2 and 3 seal components, and has a wider range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A cross-sectional view of seal No. 1, seal No. 2 and seal No. 3 of the present invention test;

[0021] Figure 2 A cross-sectional view of seal No. 2 and seal No. 3 of the present invention test;

[0022] Figure 3 is a cross-sectional view of seal No. 3 of the present invention;

[0023] Figure 4 for Figure 2 The enlarged structural diagram at A in the middle;

[0024] In the figure: 1-machine base, 2-base, 3-lower bearing assembly, 4-motor, 5-spindle, 6-transmission member, 7-test sleeve, 8-backing seal dynamic ring assembly, 9-backing seal leakage end mechanical seal, 10-lower cavity, 11-upper cavity, 12-top seat, 13-upper bearing assembly, 14-No. 1 seal, 15-No. 2 seal, 16-No. 3 seal, 17-temperature sensor, 18-positioning assembly, 19-transmission ring, 20-backing seal leakage hole, 21-circulating water outlet, 22-No. 1 sealing water injection hole, 23-No. 1 sealing pressure sensor mounting hole, 24-No. 1 sealing leakage water interface, 25-No. 2 sealing leakage water flange interface, 26-No. 3 sealing injection water flange interface, 27-No. 3 sealing leakage water flange interface, 28-tensioning assembly, 37-petal ring, 38-pressure ring, 39-pressure screw, 40-elastic gasket, 41-pin. DETAILED DESCRIPTION

[0025] The present invention is further described below in conjunction with the accompanying drawings, but the protection scope of the present invention is not limited to the following description.

[0026] like Figure 2As shown, a fluid static pressure type main pump mechanical seal test device includes a base 2, a motor 4, a main shaft 5 and a test sleeve 7. A lower cavity 10, an upper cavity 11 and a top seat 12 are fixed on the base 2 from bottom to top, wherein the upper cavity 11 and the lower cavity 10 are fixed to the base 2 by a plurality of long rod bolts, and the top seat 12 is fixed to the upper cavity 11 by a plurality of long rod bolts. The lower end of the main shaft 5 is rotatably mounted on the base 2, and the upper end is rotatably mounted on the top seat 12. The motor 4 is connected to the main shaft 5 by transmission. The main shaft 5 is fixedly mounted with a test sleeve 7, and the test sleeve 7 is mounted on the main shaft 5. On the test sleeve 7, No. 2 seal 15 and No. 3 seal 16 are installed in sequence from bottom to top, No. 2 seal 15 is a contact mechanical seal, No. 3 seal 16 is a radial end face mechanical seal, No. 2 seal 15 is located on the inner side of the upper cavity 11, and No. 3 seal 16 is located on the inner side of the No. 3 sealing cavity of the top seat 12; There is a No. 3 seal injection water flange interface 26 on the side wall of the sealing shell of the top seat 12, which is connected to the No. 3 seal leakage water pipe of the test system, and the No. 3 seal leakage water flange interface 27 on the side wall of the sealing shell of the top seat 12 is connected to the No. 3 seal leakage water pipe of the test system; In this embodiment, as Figure 3 As shown, the No. 3 seal injection water is introduced into the internal channel of the static ring of the No. 3 seal 16 through the thin tube in the sealing cavity to the No. 3 seal end face, which plays the role of cooling, lubricating the end face of the No. 3 seal 16, and flushing the end face of the No. 3 seal 16 to prevent crystallization. More importantly, the pressure of the No. 3 seal injection water is higher than the pressure of the No. 3 seal cavity, thereby preventing the medium in the No. 3 seal cavity from leaking to the atmosphere through the No. 3 seal end face. The No. 2 seal leakage water flange interface 25 on the side wall of the sealing shell of the top seat 12 is connected to the No. 2 seal leakage water pipe of the test system; a temperature sensor 17 is installed on the side wall of the upper cavity 11, and the induction head of the temperature sensor 17 is located on the inner side of the lower cavity 10, which can monitor the temperature in the sealing cavity in real time.

[0027] Furthermore, if Figure 1As shown, in order to simulate the test requirements of different working conditions of the main pump seal, the test sleeve 7 can also be installed with a No. 1 seal 14, which is located below the No. 2 seal 15. A No. 1 seal water injection hole 22 is opened on the side wall of the lower cavity 10, and the injection water pressure is controlled by the system (not shown in the figure). The No. 1 seal pressure sensor mounting hole 23 is installed with a pressure sensor to detect the pressure of the No. 1 seal cavity. A No. 1 seal leakage water interface 24 is opened on the side wall of the upper cavity 11, which is connected to the No. 1 seal leakage water pipe of the test system, and the leakage pressure is controlled by the system (not shown in the figure). The No. 1 seal water injection hole 22 and the No. 1 seal pressure sensor mounting hole 23 are arranged opposite to each other. During normal operation, high-pressure sealing water is injected through the No. 1 seal water injection hole 22 and leaks into the No. 2 seal cavity through the No. 1 seal end face. Most of it enters the system (not shown in the figure) through leakage port No. 1 and circulates, and the control system controls the pressure of sealing chamber No. 2 by controlling the pressure of leakage No. 1. A small part of it leaks into sealing chamber No. 3 through sealing end face No. 2, and merges with the leakage water of No. 3 seal injection water leaking into sealing chamber No. 3 through sealing end face No. 3 to form leakage water of No. 2 seal, which enters the system (not shown in the figure) through leakage water flange interface 25 of No. 2 seal and circulates, and the control system controls the pressure of sealing chamber No. 3 by controlling the pressure of leakage No. 2.

[0028] Simulating the normal operating conditions of the nuclear power plant, during the test, the pressure of the water injected into the No. 3 seal is slightly higher than the pressure of the No. 3 seal chamber. A small part of the water injected into the No. 3 seal enters the No. 3 seal chamber through the outer end face of the No. 3 seal and merges with the leakage water from the No. 2 seal end face described in the previous section to form the leakage water of the No. 2 seal; most of the water injected into the No. 3 seal leaks through the inner end face of the No. 3 seal to form the leakage water from the No. 3 seal and is discharged from the No. 3 seal leakage water flange interface 27. Since the pressure of the water injected into the No. 3 seal is always kept slightly higher than the pressure of the No. 3 seal chamber, the leakage water of the No. 3 seal is clean during the operation of the nuclear power plant, which can ensure that there is no harm to the atmospheric environment.

[0029] For further information, please refer to Figure 1 and Figure 2 The lower end of the test sleeve 7 is equipped with a liner seal dynamic ring assembly 8, the base is equipped with a liner seal static ring assembly, and a liner seal leakage end mechanical seal 9 is also arranged between the main shaft 5 and the base 2. The base 2 is also provided with a liner seal leakage hole 20 and a circulating water outlet 21. The function of the circulating water outlet 21 is to discharge the medium through the circulating water outlet 21 after the test is completed.

[0030] Furthermore, if Figure 1 and Figure 2 As shown, the lower end of the main shaft 5 is installed in the base 2 through the lower bearing assembly, and the upper end of the main shaft 5 is installed on the top seat 12 through the upper bearing assembly 13. The lower bearing assembly and the upper bearing assembly are both conventional bearing assemblies and will not be described in detail here.

[0031] Furthermore, if Figure 1 and Figure 2 As shown, the base 2 is fixed on the machine base 1 , the motor 4 is installed on the machine base 1 , and the motor 4 is connected to the main shaft 5 through a transmission member 6 .

[0032] In this embodiment, in order to save installation space, the output shaft of the motor 4 is parallel to the main shaft 5, the transmission member 6 is a belt, and the belt can be a V-belt or a toothed belt, etc., the output end of the motor 4 is equipped with an output pulley, and the lower end of the main shaft 5 is equipped with an input pulley, and the output pulley is connected to the input pulley through a belt transmission. The motor 4 is placed on the side, the height of the test bench is greatly reduced, the safety is higher, and the assembly, disassembly, operation and maintenance are more convenient and quick.

[0033] It should be noted that the motor 4 can also be installed coaxially with the main shaft 5, that is, the transmission member 6 can be selected as a coupling, and the motor 4 and the main shaft 5 are connected through the coupling.

[0034] Furthermore, if Figure 2 and Figure 4 As shown, the test sleeve 7 of this embodiment rotates coaxially with the main shaft 5. In this embodiment, the test sleeve 7 is fixed on the main shaft 5 by means of compression transmission. Specifically, the lower end of the test sleeve 7 abuts against the shoulder of the main shaft 5, and the upper end of the test sleeve 7 is fixed on the main shaft 5 by a positioning assembly 18. The positioning assembly 18 includes a petal ring 37, a pressure ring 38, a compression screw 39 and an elastic washer 40. The petal ring 37 is clamped on the main shaft 5. An annular step is provided on the upper end surface of the test sleeve 7, and the annular step is coaxial with the main shaft 5. The pressure ring 38 is installed in the annular step, and the tightening screw 39 passes through the petal ring 37 and is locked in the pressure ring 38. An elastic gasket 40 is provided between the pressure ring 38 and the annular step. In the actual installation process, the petal ring 37 is a two-petal structure and can be directly clamped on the main shaft 5. In order to prevent circumferential rotation between the main shaft 5 and the petal ring 37, a pin 41 can be provided on the inner wall of the petal ring 37. Correspondingly, a pin hole is opened in the clamping groove of the main shaft 5, and the pin 41 is inserted into the pin hole, thereby preventing the petal ring 37 and the main shaft 5 from relative rotation.

[0035] Furthermore, if Figure 1 and Figure 2 As shown, a transmission ring 19 is fixedly installed on the upper end of the test sleeve 7, and the transmission ring 19 is fixed to the test sleeve 7 by screws. A sealing sleeve is fixed below the transmission ring 19. The sealing sleeve is the sleeve actually installed in the main pump. The sealing sleeve is sleeved on the outside of the test sleeve 7, and the No. 2 seal 15 and the No. 3 seal 16 are installed on the outside of the sealing sleeve. During the assembly test, the test sleeve 7 does not need to be disassembled. It is only necessary to remove the transmission ring 19 from the test sleeve 7 to remove the sealing sleeve as a whole.

[0036] Furthermore, a tensioning assembly 28 for adjusting the position of the motor 4 is also installed on the machine base 1. The tensioning assembly 28 includes a fixing block and an adjusting screw. The fixing block is fixed on the machine base 1. The adjusting screw is threadedly connected to the fixing block, and the front end surface of the adjusting screw abuts against the mounting seat of the motor 4. According to the tension of the belt, the installation position of the motor 4 is adjusted through the tensioning assembly 28. Specifically, the anchor bolts of the motor 4 are loosened, the adjusting screws are turned, and the motor 4 is pushed to move. When it moves to a suitable position, the anchor bolts of the motor 4 are tightened.

[0037] 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 fluid static pressure main pump mechanical seal test device, characterized in that: It includes a base, a motor, a main shaft and a test sleeve, wherein a lower cavity, an upper cavity and a top seat are fixed on the base in sequence from bottom to top, the lower end of the main shaft is rotatably mounted on the base, and the upper end is rotatably mounted on the top seat, the motor is drivingly connected to the main shaft, a test sleeve is fixedly mounted on the main shaft, and a No. 1 seal, a No. 2 seal and a No. 3 seal are installed on the test sleeve in sequence from bottom to top, the No. 1 seal is located inside the lower cavity, the No. 2 seal is located inside the upper cavity, and the No. 3 seal is located between the upper cavity and the top seat; The No. 3 sealed water injection flange interface on the side wall of the sealed shell of the top seat is connected to the No. 3 sealed water injection pipe of the test system; The No. 3 sealing leakage water flange interface on the side wall of the sealing shell of the top seat is connected to the No. 3 sealing leakage water pipe of the test system; The No. 2 sealing leakage water flange interface on the side wall of the sealing shell of the top seat is connected to the No. 2 sealing leakage water pipe of the test system; A temperature sensor is installed on the side wall of the upper cavity, and the induction head of the temperature sensor is located inside the lower cavity; A No. 1 sealed leakage water interface is provided on the side wall of the upper cavity, which is connected to the No. 1 sealed leakage water pipe of the test system; A No. 1 sealing water injection hole and a No. 1 sealing pressure sensor installation hole are provided on the side wall of the lower cavity, and the No. 1 sealing water injection hole and the No. 1 sealing pressure sensor installation hole are arranged opposite to each other; A liner seal dynamic ring assembly is installed at the lower end of the test sleeve, a liner seal static ring assembly is installed on the base, a liner seal leakage end mechanical seal is also arranged between the main shaft and the base, and a liner seal leakage hole is also opened on the base; The lower end of the test sleeve abuts against the shoulder of the main shaft, and the upper end of the test sleeve is fixed on the main shaft through a positioning assembly, and the positioning assembly includes a petal ring, a pressure ring, a clamping screw and an elastic washer. The petal ring is clamped on the main shaft, and an annular step is provided on the upper end surface of the test sleeve, and the annular step is coaxial with the main shaft. The pressure ring is installed in the annular step, and the clamping screw passes through the petal ring and is locked in the pressure ring. An elastic washer is provided between the pressure ring and the annular step; A transmission ring is fixedly mounted on the upper end of the test sleeve, a sealing sleeve is fixed below the transmission ring, the sealing sleeve is sleeved on the outer side of the test sleeve, and the No. 2 seal and the No. 3 seal are mounted on the outer side of the sealing sleeve.

2. A fluid static pressure main pump mechanical seal test device according to claim 1, characterized in that: The lower end of the main shaft is installed in the base through a lower bearing assembly, and the upper end of the main shaft is installed on the top seat through an upper bearing assembly.

3. A fluid static pressure main pump mechanical seal test device according to claim 2, characterized in that: The base is fixed on the machine base, the motor is installed on the machine base, and the motor is connected to the main shaft through a transmission member.

4. A fluid static pressure main pump mechanical seal test device according to claim 3, characterized in that: The transmission member is a belt, an output pulley is installed at the output end of the motor, an input pulley is installed at the lower end of the main shaft, and the output pulley is connected to the input pulley through a belt transmission.

5. A fluid static pressure main pump mechanical seal test device according to claim 4, characterized in that: A tensioning assembly for adjusting the position of the motor is also installed on the machine base.

6. A fluid static pressure main pump mechanical seal test device according to claim 5, characterized in that: The tensioning assembly comprises a fixing block and an adjusting screw, wherein the fixing block is fixed on the machine base, the adjusting screw is threadably connected to the fixing block, and the front end surface of the adjusting screw abuts against the mounting base of the motor.

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