Dynamic bearing bush gap measuring device and measuring method

Abstract

The invention relates to the technical field of hydroelectric generating set operation and maintenance, and discloses a dynamic bearing bush gap measuring device and method. Comprising a machine body, an oil groove shell is connected to the interior of the machine body in an embedded mode, a bearing body base is arranged in the oil groove shell, a guide tile is arranged in the bearing body base, a main shaft is connected to the interior of the bearing body base in an embedded mode, and anti-weight bolts are connected to the side surfaces of the bearing body base in a threaded mode; according to the online monitoring method, the ultrasonic ranging technology is utilized, the thermal state gap value between the rotating shaft and the guide shoe can be measured in a non-contact mode under the condition that the main shaft rotates, the online monitoring method for the thermal state gap value of the bearing bush comprises the steps that a ranging device based on ultrasonic waves is established, the thermal state gap value between the bearing bushes can be accurately measured when a unit runs, and the accuracy of the thermal state gap value is improved. A new measurement means of the thermal state gap is provided, and online real-time dynamic measurement of the thermal state gap value between the shaft and the guide shoe can be achieved through the signal receiver and the processing device under the condition that a unit operates.

Description

Technical Field

[0001] The invention relates to the technical field of operation and maintenance of hydropower units, and in particular to a dynamic bearing clearance measuring device and a measuring method. Background Art

[0002] Traditional dynamic bearing clearance measuring devices usually use feeler gauge detection method and lead pressure detection method. Feeler gauge detection method: It is suitable for bearings with larger diameters. When the clearance is large, use a narrower feeler gauge for direct detection. For bearings with smaller diameters, the clearance is smaller and can be measured with a feeler gauge, but the side clearance of the bearing needs to be measured with a feeler gauge of moderate thickness. When measuring, it should be noted that the length of the gap should not be less than 2 / 3 of the length of the bearing. Lead pressure detection method: It is more accurate than the feeler gauge detection method, but the operation is more cumbersome. The lead wire used should be soft and of moderate diameter, and the ideal diameter is 1.5 to 2 times the clearance. The operation steps include: Apply grease to the lead wire, place it on the upper part of the bearing and the joint of the upper and lower bearings on both sides, cover the bearing cover and tighten the bolts, then loosen the bolts, remove the bearing cover, use a micrometer to detect the thickness of the flattened lead wire, and find the average value of the bearing top clearance. Measuring tools and equipment: Mainly use micrometers and feeler gauges for measurement. Micrometers are used for high-precision measurements, while feeler gauges are suitable for situations with general precision requirements. The measurement steps are as follows: open the bearing cover, select a lead wire of appropriate diameter, cut it into small sections and apply grease. Place the lead wire on the upper part of the bearing and at the junction of the upper and lower bearings on both sides, cover the bearing cover and tighten the bolts. Loosen the bolts, remove the bearing cover, and use a micrometer to check the thickness of the flattened lead wire. Record the data and calculate the average value of the bearing top clearance. Through these methods, the bearing clearance can be accurately measured to ensure the normal operation of mechanical equipment and the service life of the bearing. The outside of the guide bearing is an oil tank cover to prevent the lubricating oil from overflowing. The bearing clearance value is generally measured with a feeler gauge when the unit is shut down, and the oil tank cover needs to be disassembled. At this time, the cold clearance value is measured. The cold gap value refers to the gap value when the unit is stationary, while the hot gap value when the unit is running and rotating can better reflect the actual state of the unit during operation. Its size will change with the rotation of the main shaft, but there is currently no effective method to measure the hot gap value. The eddy current sensor used for unit swing measurement is generally installed on the oil tank cover. Due to structural reasons, the oil tank cover will vibrate to a certain extent as the unit runs, so the swing value measured is actually a relative swing rather than an absolute swing. The internal defects of the anti-weight bolts require the bolts to be removed when the unit is shut down for ultrasonic flaw detection. Currently, it is impossible to monitor them online in real time. How to judge whether the hot gap of the bearing inside the closed guide bearing is normal during the operation of the hydro-turbine generator set, and whether the swing of the main shaft can be measured more accurately, and whether the internal defects of the anti-weight bolts can be monitored in real time are problems that need to be solved in the operation and maintenance of hydro-turbine generator sets. Summary of the invention

[0003] 1. Technical issues to be resolved In view of the deficiencies in the prior art, the present invention provides a dynamic bearing clearance measurement device and a measurement method. By utilizing ultrasonic ranging technology, it is possible to achieve non-contact measurement of the hot clearance value between the rotating shaft and the guide bush when the main shaft is rotating. An online monitoring method for the hot clearance value of the bearing bush is to establish an ultrasonic ranging device, which is capable of accurately measuring the hot clearance value between the bearing bushes when the unit is running, and provides a new means for measuring the hot clearance. Through a post-placed signal receiver and a processing device, it is possible to achieve online real-time dynamic measurement of the hot clearance value between the shaft and the guide bush when the unit is running. The measured hot clearance value between the bearing bushes is the spindle swing, and its measurement result is closer to the absolute swing value, which can be compared with the traditional eddy current sensor. The devices interact to identify and verify each other, which improves the measurement accuracy of the swing and axis trajectory. The ultrasonic probe is fixed at the rear end of the anti-weight bolt, and the anti-weight bolt and the bearing body base need to withstand the radial impact force of the main shaft, so it belongs to a relatively fixed foundation. The swing measured on this basis is closer to the absolute swing, and the function of ultrasonic flaw detection is retained. It can monitor in real time whether there are internal defects in the anti-weight bolt, effectively reflect the gap value between the main shaft and the guide bush, calculate the axis trajectory, and cross-identify and verify with the axis trajectory measured by the traditional eddy current sensor to improve the accuracy of the result. The ultrasonic detection sensor is installed in the oil tank. At the same time, the oil in the oil tank can be used as the coupling medium of the sensor, which has the advantages of adapting to the oil environment, etc.

[0004] (II) Technical solution In order to solve the above technical problems, the present invention provides the following technical solutions: comprising a machine body, an oil tank shell is interlocked and connected inside the machine body, a bearing body base is arranged inside the oil tank shell, a guide tile is arranged inside the bearing body base, a main shaft is interlocked and connected inside the bearing body base, and the main shaft and the guide tile are fitted together, the side surfaces of the bearing body base are threadedly connected with anti-weight bolts, the upper surface of the guide tile is provided with an ultrasonic detection sensor, the upper surface of the oil tank shell is threadedly connected with an oil tank cover, and the upper surface of the oil tank cover is provided with an eddy current sensor.

[0005] Through the above technical scheme, the ultrasonic-based distance measuring device can accurately measure the hot clearance value between the bearings when the unit is running, providing a new means of measuring the hot clearance. The measured hot clearance value between the bearings is the spindle swing, and its measurement result is closer to the absolute swing value. It can interact and identify with the traditional eddy current sensor and verify each other, thereby improving the measurement accuracy of the swing and axis trajectory, retaining the function of ultrasonic flaw detection, and can monitor in real time whether there are internal defects in the anti-weight bolts. The ultrasonic probe can be installed in the oil tank to adapt to the oil environment, and the lubricating oil also acts as a coupling agent.

[0006] Preferably, a dust cover is provided on the upper surface of the oil tank cover, and the dust cover is sleeve-connected to the main shaft, and an opening is provided on the front surface of the dust cover.

[0007] Through the above technical solution, the dust cover can be used to cover the main shaft extending from the inside of the oil tank cover to prevent external dust from entering the main shaft and affecting the detection effect of the gap between the main shaft and the bearing surface.

[0008] Preferably, an observation window is threadedly connected to the upper surface of the oil tank cover, and a threaded rod is threadedly connected to the upper surface of the body.

[0009] Through the above technical solution, the gap detection process between the main shaft and the tile surface can be observed using the observation window.

[0010] Preferably, a cooling pipe is provided inside the oil tank shell, and the cooling pipe is circumferentially connected to the outside of the bearing body base.

[0011] Through the above technical solution, the entire bearing is immersed in lubricating oil. When the main shaft rotates, the lubricating oil will form an oil film between the main shaft and the bearing surface to reduce friction. At the same time, the cooling device continuously takes away heat and controls the oil temperature to achieve a cooling effect.

[0012] Preferably, a mounting plate is fixedly connected to the inner wall of the oil tank shell, and the mounting plate is in contact with the upper surface of the cooling pipe.

[0013] Through the above technical solution, the cooling tube is squeezed by the mounting plate, so that the shaking of the cooling tube can be reduced when the main shaft rotates.

[0014] Preferably, the number of the guide tiles is 6-8 to hold the main shaft, and one end of the anti-weight bolt extends into the bearing body base to support the back of the guide tile.

[0015] Through the above technical solution, the anti-weight bolts and the bearing body base need to withstand the radial impact force of the main shaft, so it belongs to a relatively fixed foundation. The swing measured on this basis is closer to the absolute swing.

[0016] Preferably, the gap between the tile surface of the guide tile and the main shaft is called the bearing clearance value, and the ultrasonic probe of the ultrasonic detection sensor is fixed at the rear end of the anti-weight bolt.

[0017] Through the above technical solution, the function of ultrasonic flaw detection is retained, and whether there are internal defects in the anti-weight bolts can be monitored in real time.

[0018] Preferably, a signal receiver is provided on the upper surface of the oil tank cover, and the signal receiver is electrically connected to the ultrasonic detection sensor and the eddy current sensor.

[0019] Through the above technical solution, through the post-placed signal receiver and processing device, it is possible to achieve online real-time dynamic measurement of the hot clearance value between the shaft and the guide bushing when the unit is running.

[0020] Preferably, the eddy current sensor measures the distance between the rotating spindle and the probe by a non-contact method.

[0021] Through the above technical solution, interactive identification and mutual verification with traditional eddy current sensors are achieved, thereby improving the measurement accuracy of the swing and axis trajectory.

[0022] A dynamic bearing clearance measurement method comprises the following steps: S1. The number of ultrasonic detection sensors is consistent with the number of guide tiles, one data acquisition instrument and one host computer. The ultrasonic detection sensor is arranged at the rear end of the anti-weight bolt in the oil tank shell. The arrangement method can be direct welding or welding and bolt connection through a fixed bracket. The sensor is connected to the acquisition instrument through the data line leading out of the oil tank, and the acquisition instrument is controlled by the host computer; S2. The ultrasonic distance measurement method is used to measure the gap value between the bearing surface and the main shaft. According to the principle of ultrasonic distance measurement, when the ultrasonic wave passes through the cross section, it will be reflected. The distance of the cross section can be measured by using the relationship between the sound speed and the reflection time. Therefore, the sound wave emitted by the ultrasonic detection sensor installed at the rear end of the anti-weight bolt will generate reflected waves from near to far at the front end face of the anti-weight bolt, the bearing back, the bearing surface, and the main shaft surface. Therefore, four distances will be measured, namely, the distance A from the front end face of the anti-weight bolt, the distance B from the bearing back, the distance C from the bearing surface, and the distance D from the main shaft surface. At this time, the bearing gap value = DC, and the distance between the bearing back and the anti-weight bolt = BA; S3. Similar to the principle of traditional eddy current measurement of swing, the measured distance A from the probe to the spindle surface is the swing waveform, and the peak value is the swing; S4. When there are defects inside the anti-weight bolt, the ultrasonic ranging will cause new reflected waves different from the above four sections. The abnormal reflected waves can be used to identify whether there are abnormal defects inside the anti-weight bolt and determine the location of the fault.

[0023] Compared with the prior art, the present invention provides a dynamic bearing clearance measuring device and a measuring method, which have the following beneficial effects: 1. The present invention utilizes ultrasonic ranging technology to realize non-contact measurement of the hot clearance value between the rotating shaft and the guide bush when the main shaft is rotating. The online monitoring method of the hot clearance value of the bearing bush is to establish an ultrasonic ranging device, which can accurately measure the hot clearance value between the bearing bushes when the unit is running, and provides a new hot clearance measurement method. Through the post-placed signal receiver and processing device, the online real-time dynamic measurement of the hot clearance value between the shaft and the guide bushes can be realized when the unit is running. The measured hot clearance value between the bearing bushes is the spindle swing, and the measurement result is closer to the absolute swing value, which can be interactively identified and mutually verified with the traditional eddy current sensor, thereby improving In order to improve the measurement accuracy of the swing and the axis trajectory, the ultrasonic probe is fixed at the rear end of the anti-weight bolt, and the anti-weight bolt and the bearing body base need to withstand the radial impact force of the main shaft, so it belongs to a relatively fixed foundation. The swing measured on this basis is closer to the absolute swing, and the function of ultrasonic flaw detection is retained. It can monitor in real time whether there are internal defects in the anti-weight bolt, effectively reflect the gap value between the main shaft and the guide bushing, calculate the axis trajectory, and cross-recognize and verify with the axis trajectory measured by the traditional eddy current sensor to improve the accuracy of the result. The ultrasonic detection sensor is installed in the oil tank. At the same time, the oil in the oil tank can be used as the coupling medium of the sensor, which has the advantage of adapting to the oil environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall split structure of the present invention; Figure 2 It is a schematic diagram of the top view of the internal structure of the oil tank shell of the present invention.

[0025] Among them: 1. Machine body; 2. Threaded rod; 3. Oil tank shell; 4. Oil tank cover; 5. Eddy current sensor; 6. Main shaft; 7. Dust cover; 8. Opening; 9. Observation window; 10. Mounting plate; 11. Bearing body base; 12. Anti-weight bolt; 13. Guide tile; 14. Ultrasonic detection sensor; 15. Cooling pipe. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] Embodiment 1: See also Figure 1-2A dynamic bearing clearance measuring device comprises a machine body 1, wherein the machine body 1 is internally engaged with an oil tank shell 3, the oil tank shell 3 is internally provided with a bearing body base 11, the bearing body base 11 is internally provided with a guide tile 13, the bearing body base 11 is internally engaged with a main shaft 6, and the main shaft 6 is fitted with the guide tile 13, and the ultrasonic ranging technology is used to realize non-contact measurement of the hot clearance value between the rotating shaft and the guide tile when the main shaft 6 rotates, which can effectively reflect the clearance value between the main shaft 6 and the guide tile, calculate the axis trajectory, and cross-recognize and verify with the axis trajectory measured by the traditional eddy current sensor 5 to improve the accuracy of the result, the clearance between the tile surface and the main shaft 6 is called the bearing clearance value, which is an important mechanical parameter, and its size is controlled by adjusting the in and out amount of the anti-weight bolt 12, and the centering of the entire shaft system is achieved by adjusting the bearing clearance value during the turning, the side surface of the bearing body base 11 is threadedly connected with the anti-weight bolt 12, and the internal defects of the anti-weight bolt 12 can be monitored in real time, which is equivalent to installing A real-time ultrasonic flaw detection device is provided. An ultrasonic detection sensor 14 is arranged on the upper surface of the guide tile 13. The ultrasonic detection sensor is installed in the oil tank. At the same time, the oil in the oil tank can be used as a coupling medium for the sensor, which has the advantage of adapting to an oily environment. Ultrasonic ranging technology is widely used. Its basic principle is to use the reflection effect of ultrasonic waves. The distance from the sound wave to the reflecting surface is calculated by the sound wave velocity and the reflection time. It is often used in radar, metal flaw detection and other occasions. After the ultrasonic probe is coated with coupling agent, it is closely attached to the metal part to be tested. When the ultrasonic wave contacts the interface, part of the sound wave will be reflected back. If it contacts the crack defect inside the metal part in the middle, the ultrasonic wave will return a defect pulse signal. The current scanning range that the ultrasonic flaw detector can detect is: 0~28000mm steel longitudinal wave, ambient temperature: (-20~70)℃, the upper surface of the oil tank shell 3 is threadedly connected with an oil tank cover 4, and the upper surface of the oil tank cover 4 is provided with an eddy current sensor 5, which refers to the relative movement distance between the rotating part and the stationary reference object.Generally, most of the current swing measurement methods for hydropower stations are to use eddy current sensors 5, which are installed on a relatively fixed base (such as an oil pan cover) to measure the distance between the rotating main shaft 6 and the probe by a non-contact method. The swing of the unit has clear limit requirements in the national standard. In addition, the axis trajectory diagram of the main shaft 6 can be drawn using the measured swing value. The number of guide tiles 13 is 6-8 pieces, which hold the main shaft 6. The anti-weight bolt 12 extends into one end of the bearing body base 11 to support the back of the guide tile 13. The gap between the tile surface of the guide tile 13 and the main shaft 6 is called the bearing clearance value. The ultrasonic probe of the ultrasonic detection sensor 14 is fixed at the rear end of the anti-weight bolt 12. The ultrasonic probe used is fixed at the rear end of the anti-weight bolt 12, and the anti-weight bolt 12 and the bearing body base 11 need to withstand the radial impact force of the main shaft 6, so it belongs to a relatively fixed foundation. The swing measured on this basis is closer to the absolute swing. The upper surface of the oil tank cover 4 is provided with a signal The receiver, and the signal receiver are electrically connected to the ultrasonic detection sensor 14 and the eddy current sensor 5. Through the post-placed signal receiver and processing device, the online real-time dynamic measurement of the hot gap value between the shaft and the guide bush can be realized when the unit is running. The eddy current sensor 5 measures the distance between the rotating main shaft 6 and the probe by a non-contact method, and establishes an ultrasonic-based distance measuring device, which can accurately measure the hot gap value between the bearing bushes when the unit is running, providing a new means of measuring the hot gap. The measured hot gap value between the bearing bushes is the swing of the main shaft 6, and the measurement result is closer to the absolute swing value. It can interact and verify with the traditional eddy current sensor 5, improve the measurement accuracy of the swing and the axis trajectory, retain the function of ultrasonic flaw detection, and can monitor in real time whether the anti-weight bolt 12 has internal defects. The ultrasonic probe can be installed in the oil tank to adapt to the oil environment, and the lubricating oil also acts as a coupling agent.

[0028] A dust cover 7 is provided on the upper surface of the oil tank cover 3, and the dust cover 7 is sleeve-connected with the main shaft 6. The front surface of the dust cover 7 is provided with an opening 8. An observation window 9 is threadedly connected to the upper surface of the oil tank cover 4. A threaded rod 2 is threadedly connected to the upper surface of the body 1. A cooling pipe 15 is provided inside the oil tank shell 3, and the cooling pipe 15 is circumferentially connected to the outside of the bearing body base 11. The main shaft 6 is embraced by 6 to 8 guide bushes evenly arranged on the circumference. The anti-weight bolt 12 is fixed in the bearing body base 11 and supports the bush back. The entire bearing is immersed in lubricating oil. When the main shaft 6 rotates, the lubricating oil will form an oil film between the main shaft 6 and the bush surface to reduce friction. At the same time, the cooling device continuously takes away heat to control the oil temperature to achieve a cooling effect. The inner wall of the oil tank shell 3 is fixedly connected with a mounting plate 10, and the mounting plate 10 is in contact with the upper surface of the cooling pipe 15.

[0029] Embodiment 2: A dynamic bearing clearance measurement method comprises the following steps: S1, the number of ultrasonic detection sensors 14 is consistent with the number of guide tiles 13, a data acquisition instrument and a host computer, the ultrasonic detection sensor 14 is arranged at the rear end of the anti-weight bolt 12 in the oil tank shell 3, and the arrangement method can be directly welded or welded and bolted through a fixed bracket. The sensor is connected to the acquisition instrument through a data line leading out of the oil tank, and the acquisition instrument is controlled by the host computer; S2. The ultrasonic distance measurement method is used to measure the gap value between the bearing surface and the main shaft 6. According to the principle of ultrasonic distance measurement, when the ultrasonic wave passes through the cross section, it will be reflected. The distance of the cross section can be measured by using the relationship between the speed of sound and the reflection time. Therefore, the sound wave emitted by the ultrasonic detection sensor 14 installed at the rear end of the anti-weight bolt 12 will generate reflected waves from the front end face of the anti-weight bolt 12, the bearing back, the bearing surface, and the main shaft 6 surface from near to far. Therefore, four distances will be measured, namely, the distance A from the front end face of the anti-weight bolt 12, the distance B from the bearing back, the distance C from the bearing surface, and the distance D from the main shaft 6 surface. At this time, the bearing gap value = DC, and the distance between the bearing back and the anti-weight bolt 12 = BA; S3. Similar to the principle of traditional eddy current measurement of swing, the measured distance A from the probe to the surface of the spindle 6 is the swing waveform, and the peak value is the swing; S4. When there is a defect inside the anti-weight bolt 12, it will cause the ultrasonic ranging to have a new reflected wave different from the above four sections. The abnormal reflected wave can be used to identify whether there is an abnormal defect inside the anti-weight bolt 12 and determine the location of the fault point.

[0030] Firstly, a dynamic bearing clearance detection system including ultrasonic detection sensor, acquisition instrument and host computer is established. Then, the acquisition system is used to collect signals as the basis for identification and judgment. Furthermore, the bearing clearance value, the main shaft 6 swing value and the internal defects of the anti-weight bolt 12 are determined according to the judgment method. Finally, operation and maintenance suggestions are given according to the judgment results. For the detection and positioning problems of bearing clearance, main shaft 6 swing and internal defects of anti-weight bolt 12, relevant measurement and positioning methods are proposed. By using ultrasonic wave to dynamically measure the clearance value, a new method for measuring bearing clearance, main shaft 6 swing and internal defects of anti-weight bolt 12 is provided, which provides a means for online monitoring of guide bearings of hydropower units.

[0031] When in use, the main shaft 6 is held by 6 to 8 guide bearings evenly arranged on the circumference, the anti-weight bolts 12 are fixed in the bearing body base 11 and support the bearing back, and the entire bearing is immersed in lubricating oil. When the main shaft 6 rotates, the lubricating oil will form an oil film between the main shaft 6 and the bearing surface to reduce friction. At the same time, the cooling device continuously takes away heat and controls the oil temperature to achieve a cooling effect. In addition, the gap between the bearing surface and the main shaft 6 is called the bearing clearance value, which is an important mechanical parameter. Its size is controlled by adjusting the entry and exit amount of the anti-weight bolts 12. When turning the car, the centering of the entire shaft system is achieved by adjusting the bearing clearance value. Generally, the gap value is measured by a feeler gauge, and the distance from the sound wave to the reflecting surface is calculated by the sound wave velocity and the reflection time. It is often used in radar, metal flaw detection and other occasions. After the ultrasonic probe is coated with coupling agent, it is tightly attached to the metal part to be measured. When the ultrasonic wave contacts the interface, part of the sound wave will be reflected back. If it contacts the crack defect inside the metal part in the middle, the ultrasonic wave will return a defect pulse signal. When there is a defect inside the anti-weight bolt 12, it will cause the ultrasonic ranging to appear a new reflected wave different from the above four sections. The abnormal reflected wave can be used to identify whether there is an abnormal defect inside the anti-weight bolt 12, and the fault point can be determined. Finally, operation and maintenance suggestions can be given based on the judgment results.

[0032] 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 dynamic bearing clearance measuring device, comprising a body (1), characterized in that: The body (1) is internally connected with an oil tank shell (3), the oil tank shell (3) is internally provided with a bearing body base (11), the bearing body base (11) is internally provided with a guide tile (13), the bearing body base (11) is internally connected with a main shaft (6), and the main shaft (6) and the guide tile (13) are fitted together, the side surfaces of the bearing body base (11) are threadedly connected with anti-weight bolts (12), the upper surface of the guide tile (13) is provided with an ultrasonic detection sensor (14), the upper surface of the oil tank shell (3) is threadedly connected with an oil tank cover (4), and the upper surface of the oil tank cover (4) is provided with an eddy current sensor (5).

2. A dynamic bearing clearance measuring device according to claim 1, characterized in that: A dust cover (7) is provided on the upper surface of the oil tank cover (3), and the dust cover (7) is sleeve-connected to the main shaft (6), and an opening (8) is provided on the front surface of the dust cover (7).

3. A dynamic bearing clearance measuring device according to claim 1, characterized in that: The upper surface of the oil tank cover (3) is threadedly connected to an observation window (9), and the upper surface of the machine body (1) is threadedly connected to a threaded rod (2).

4. A dynamic bearing clearance measuring device according to claim 1, characterized in that: A cooling pipe (15) is arranged inside the oil tank shell (3), and the cooling pipe (15) is circumferentially connected to the outside of the bearing body base (11).

5. A dynamic bearing clearance measuring device according to claim 1, characterized in that: A mounting plate (10) is fixedly connected to the inner wall of the oil tank shell (3), and the mounting plate (10) is in contact with the upper surface of the cooling pipe (15).

6. A dynamic bearing clearance measuring device according to claim 1, characterized in that: The number of the guide tiles (13) is 6 to 8 and they hold the main shaft (6). One end of the anti-weight bolt (12) extends into the bearing body base (11) and supports the back of the guide tiles (13).

7. A dynamic bearing clearance measuring device according to claim 1, characterized in that: The gap between the tile surface of the guide tile (13) and the main shaft (6) is called the bearing gap value, and the ultrasonic probe of the ultrasonic detection sensor (14) is fixed to the rear end of the anti-weight bolt (12).

8. A dynamic bearing clearance measuring device according to claim 1, characterized in that: A signal receiver is provided on the upper surface of the oil tank cover (4), and the signal receiver is electrically connected to the ultrasonic detection sensor (14) and the eddy current sensor (5).

9. A dynamic bearing clearance measuring device according to claim 1, characterized in that: The eddy current sensor (5) measures the distance between the rotating spindle (6) and the probe by a non-contact method.

10. A dynamic bearing clearance measurement method according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1, the number of ultrasonic detection sensors (14) is consistent with the number of guide tiles (13), a data acquisition instrument and a host computer, the ultrasonic detection sensor (14) is arranged at the rear end of the anti-weight bolt (12) in the oil tank shell (3), and the arrangement method can be direct welding or welding and bolt connection through a fixed bracket; the sensor is connected to the acquisition instrument through a data line leading out of the oil tank, and the acquisition instrument is controlled by the host computer; S2. The ultrasonic distance measurement method is used to measure the gap value between the bearing surface and the main shaft (6). According to the principle of ultrasonic distance measurement, when the ultrasonic wave passes through the cross section, it will be reflected. The distance of the cross section can be measured by using the relationship between the sound speed and the reflection time. Therefore, the sound wave emitted by the ultrasonic detection sensor (14) installed at the rear end of the anti-weight bolt (12) will generate reflected waves from the front end face of the anti-weight bolt (12), the bearing back, the bearing surface, and the main shaft (6) surface from near to far. Therefore, four distances will be measured, namely, the distance A from the front end face of the anti-weight bolt (12), the distance B from the bearing back, the distance C from the bearing surface, and the distance D from the main shaft (6) surface. At this time, the bearing gap value = DC, and the distance between the bearing back and the anti-weight bolt = BA; S3. Similar to the principle of traditional eddy current measurement of swing, the measured distance A from the probe to the surface of the spindle (6) is the swing waveform, and the peak value is calculated to be the swing; S4. When there is a defect inside the anti-weight bolt (12), it will cause the ultrasonic ranging to produce a new reflected wave that is different from the above four sections. Based on the abnormal reflected wave, it can be identified whether there is an abnormal defect inside the anti-weight bolt (12) and the location of the fault point can be determined.

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