Nuclear power plant grease identification simulation bench

Abstract

The application discloses a nuclear power station lubricating grease identification simulation bench, which comprises a bearing body, a deep groove ball bearing, a roller bearing, an angular contact ball bearing, a pump shaft and a driving device; the bearing body is sleeved on the pump shaft, and the bearing body is provided with a first bearing chamber for containing the deep groove ball bearing, a second bearing chamber for containing the roller bearing and a third bearing chamber for containing the angular contact ball bearing; the driving device is used for driving the pump shaft and the bearing body, the deep groove ball bearing, the roller bearing and the angular contact ball bearing on the pump shaft to rotate at a higher speed relative to an original equipment; the nuclear power station lubricating grease identification simulation bench has a higher rotating speed and a smaller size relative to the original equipment using lubricating grease, and has an oil supplementing period and a viscosity ratio close to those of the original equipment. The design principle of the lubricating grease identification simulation bench is determined, and the rotating speed of the simulation bench relative to the original equipment is increased, so that the size of the simulation bench is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of nuclear power plant simulation test equipment, and in particular to a nuclear power plant lubricating grease identification simulation bench. BACKGROUND

[0002] Nuclear safety equipment in nuclear power plants must adapt to various operating conditions and operating environments during its life cycle. In order to ensure that the accident state of the nuclear safety equipment meets the function, the equipment needs to be identified, including laboratory tests (even field tests) or analysis (calculation, simulation, etc.), or even a combination of the two methods. Different standard systems (such as RCC-E of French pressurized water reactor) have different specific ways of identification, but both are environmental identification of irradiation and heat.

[0003] In nuclear power plants, the bearings of nuclear safety equipment are usually lubricated by lubricating grease to ensure normal operation during the working period. Failure of the lubricating grease can cause significant damage and failure of the nuclear safety equipment. Therefore, understanding whether the lubricating grease in the nuclear safety equipment is effective, sufficient, and timely supplementing or replacing the lubricating grease is an important means to ensure the normal operation of the nuclear safety equipment. Currently, the identification of lubricating grease in China is mainly with the equipment. The equipment using lubricating grease is mostly medium and large equipment. For example, in a CPR unit, the main equipment using lubricating grease in the nuclear island is the residual heat removal pump. The residual heat removal pump (not including the motor) is 1.6 meters long, 1.7 meters high, and 1.7 meters wide. If rotation identification with the original equipment is to be achieved, the space requirements for irradiation environment and heat environment are relatively large, and the requirements for related irradiation sources and heat test furnaces are relatively high. Currently, it is basically impossible to achieve.

[0004] Based on this, it is necessary to propose a solution that can identify lubricating grease under limited space, limited heat and irradiation conditions. SUMMARY

[0005] The technical problem to be solved by the present application is to provide a nuclear power plant lubricating grease identification simulation bench.

[0006] The technical scheme adopted by the present application to solve the technical problem is: a nuclear power plant lubricating grease identification simulation bench is constructed, which comprises a bearing body, a deep groove ball bearing, a roller bearing, an angular contact ball bearing, a pump shaft, and a driving device.

[0007] The bearing body is sleeved on the pump shaft, and the bearing body is provided with a first bearing chamber for accommodating the deep groove ball bearing, a second bearing chamber for accommodating the roller bearing, and a third bearing chamber for accommodating the angular contact ball bearing.

[0008] The driving device is used for driving the pump shaft and the bearing body, the deep groove ball bearing, the roller bearing and the angular contact ball bearing on the pump shaft to rotate at a speed n1, and the speed n1 is greater than the rotating speed of the pump shaft in the original equipment.

[0009] Preferably, the average diameter of the deep groove ball bearing, the roller bearing and the angular contact ball bearing, and the rotating speed of the pump shaft are calibrated by formula (1);

[0010] n1d1=Kn2d2 (1)

[0011] Wherein:

[0012] n1 is the rotating speed of the deep groove ball bearing, the roller bearing and the angular contact ball bearing, r / min;

[0013] d1 is the average diameter of the deep groove ball bearing, the roller bearing or the angular contact ball bearing, mm;

[0014] K is a constant, and the value range is 0.85≤K≤1.15;

[0015] n2 is the rotating speed of the deep groove ball bearing of the original equipment, the roller bearing of the original equipment and the angular contact ball bearing of the original equipment, r / min;

[0016] d2 is the average diameter of the deep groove ball bearing of the original equipment, the roller bearing of the original equipment or the angular contact ball bearing of the original equipment, mm;

[0017] The deep groove ball bearing, the roller bearing and the angular contact ball bearing calibrated by formula (1) are tested for the grease replenishment period t and the viscosity ratio k, and if the error value of the grease replenishment period t or the viscosity ratio k of the deep groove ball bearing, the roller bearing and the angular contact ball bearing relative to the deep groove ball bearing of the original equipment, the roller bearing of the original equipment and the angular contact ball bearing of the original equipment is greater than 15%, the parameters of formula (1) are readjusted for calibration.

[0018] Preferably, the deep groove ball bearing, the roller bearing and the angular contact ball bearing are arranged in sequence along the axial direction of the pump shaft; and the nuclear power station grease identification simulation bench further comprises a radial force loading assembly for applying pressure to the roller bearing in the radial direction of the pump shaft.

[0019] Preferably, the second bearing chamber is provided with at least two first fixing bases arranged in radial correspondence, and the first fixing base is provided with a positioning hole.

[0020] The radial force loading assembly comprises two groups of radially corresponding compression members, positioning columns, first elastic members and second fixed bases; one end of the positioning column is inserted into the positioning hole, and the other end is threadedly connected with the compression member; the first elastic member abuts against the first fixed base and the compression member; the second fixed base is sleeved on the first fixed base and the compression member.

[0021] Preferably, the first bearing chamber forms a first oil seal structure and a second oil seal structure on both sides of the deep groove ball bearing respectively; the second bearing chamber forms a third oil seal structure and a fourth oil seal structure on both sides of the roller bearing respectively; and the third bearing chamber forms a fifth oil seal structure and a sixth oil seal structure on both sides of the angular contact ball bearing respectively.

[0022] Preferably, the nuclear power plant grease identification simulation bench further comprises an axial force loading assembly for applying pressure to the angular contact ball bearing along the axial direction of the pump shaft.

[0023] Preferably, the number of angular contact ball bearings is two, and a spacing ring is arranged between the two angular contact ball bearings, and the inner rings of the two angular contact ball bearings abut against the inner side of the spacing ring.

[0024] The axial force loading assembly comprises a third fixed base, an elastic member baffle, a second elastic member, and an elastic member base; the third fixed base is fixedly connected to the outer surface of the third bearing chamber, the elastic member baffle is arranged inside the third fixed base, the elastic member baffle, the second elastic member, the elastic member base, the sixth oil seal structure and the angular contact ball bearing are sequentially arranged and abut against each other along the axial direction of the pump shaft.

[0025] Preferably, the bearing body is provided with an exhaust chamber, the exhaust chamber is communicated with the first bearing chamber, the second bearing chamber and the third bearing chamber; the pump shaft is a hollow structure, the pump shaft is provided with a plurality of first through holes, and the first through holes are communicated with the exhaust chamber;

[0026] The bearing body is provided with a first threaded hole and a plug, the first threaded hole is communicated with the exhaust chamber and the outside, and the plug is detachably connected to the first threaded hole.

[0027] Preferably, the nuclear power plant grease identification simulation bench further comprises a shaft sleeve, the shaft sleeve is sleeved outside the plurality of first through holes of the pump shaft, the shaft sleeve is provided with a second through hole communicated with the plurality of first through holes and the exhaust chamber; a disc is arranged on each side of the shaft sleeve located on both sides of the plurality of second through holes, and a gap is left between the disc and the inner wall of the bearing body.

[0028] Preferably, the nuclear power plant grease identification simulation bench further comprises two positioning baffles, and the two positioning baffles are arranged on both sides of the second bearing chamber respectively.

[0029] The present application has the following beneficial effects: by determining the design principle of the grease identification simulation bench, the rotational speed of the simulation bench relative to the original equipment is increased, thereby reducing the equipment size of the simulation bench, while ensuring that the simulation bench and the original equipment have similar grease oiling periods and viscosity ratios, facilitating more accurate identification of the grease in a limited space; at the same time, the radial and axial variable loads of the bearing are designed, so that the loading and adjustment of the bearing can be realized. BRIEF DESCRIPTION OF DRAWINGS

[0030] The present application will be further described below in conjunction with the drawings and embodiments, wherein:

[0031] Figure 1 is a structural schematic diagram of a nuclear power plant grease identification simulation bench in some embodiments of the present application;

[0032] Figure 2 is a functional relationship diagram of the grease oiling period t and the speed coefficient A in some embodiments of the present application;

[0033] Figure 3 is a functional relationship diagram of the rated viscosity υ1 and the bearing average diameter dm in some embodiments of the present application;

[0034] Figure 4 is a local enlarged structural schematic diagram at the first bearing chamber in some embodiments of the present application;

[0035] Figure 5 is a local enlarged structural schematic diagram at the second bearing chamber in some embodiments of the present application;

[0036] Figure 6 is a local enlarged structural schematic diagram at the third bearing chamber in some embodiments of the present application. DETAILED DESCRIPTION

[0037] In order to have a clearer understanding of the technical features, objectives and effects of the present application, the specific embodiments of the present application will be described in detail with reference to the drawings. In the following description, it should be understood that the directions or positional relationships indicated by “front”, “rear”, “upper”, “lower”, “left”, “right”, “vertical”, “horizontal”, “vertical”, “horizontal”, “top”, “bottom”, “inner”, “outer”, “head”, “tail” and the like are based on the directions or positional relationships shown in the drawings, constructed and operated in a particular direction, and are only for the convenience of describing the technical solutions, and should not be understood as indicating that the devices or elements referred to must have a particular direction, therefore, it should not be understood as a limitation on the present application.

[0038] It should be noted that, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting", "fixing", "setting" and the like should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements or the interaction relationship between two elements. When an element is referred to as "on" or "below" another element, the element can be "directly" or "indirectly" above the other element, or one or more intervening elements can be present. The terms "first", "second", "third" and the like are only for the convenience of describing the technical solutions, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features with "first", "second", "third" and the like can be explicitly or implicitly included one or more of the features. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0039] Figure 1 A nuclear power plant grease identification simulation bench in some embodiments of the present application is shown, which can be used to simulate the original equipment of the nuclear power plant using grease to carry out grease identification test, wherein the original equipment includes a deep groove ball bearing, two roller bearings and a pair of angular contact ball bearings, one of the two roller bearings is a pump roller bearing. The nuclear power plant grease identification simulation bench can include a bearing body 10, a deep groove ball bearing 20, a roller bearing 30, an angular contact ball bearing 40 and a pump shaft 50. The deep groove ball bearing 20, the roller bearing 30 and the angular contact ball bearing 40 are arranged in sequence along the pump shaft 50 in the axial direction. The bearing body 10 is sleeved on the pump shaft 50, and the bearing body 10 is provided with a first bearing chamber 11 for accommodating the deep groove ball bearing 20, a second bearing chamber 12 for accommodating the roller bearing 30 and a third bearing chamber 13 for accommodating the angular contact ball bearing 40. The grease to be identified is arranged in the first bearing chamber 11, the second bearing chamber 12 and the third bearing chamber 13, and whether the grease can remain effective within a specified time is identified through the rotation of the deep groove ball bearing 20, the roller bearing 30 and the angular contact ball bearing 40.

[0040] In addition, the nuclear power plant grease identification simulation bench further includes a driving device for driving the pump shaft 50 together with the bearings thereon to rotate at a speed n1, which is greater than the rotation speed n2 of each bearing in the original equipment. Since the inner ring of each bearing (referring to the deep groove ball bearing 20, the roller bearing 30 and the angular contact ball bearing 40 described above) is in interference fit with the pump shaft, the rotation speed of the pump shaft is the same as that of the bearing inner ring, and hereinafter the rotation speed of the bearing inner ring is also referred to as the rotation speed of the bearing.

[0041] And, in the nuclear power plant grease identification simulation bench, the error values of the oil replenishment period t and the viscosity ratio k of the deep groove ball bearing 20, the roller bearing 30 and the angular contact ball bearing 40 relative to the oil replenishment period t and the viscosity ratio k of the deep groove ball bearing of the original equipment, the roller bearing of the original equipment and the angular contact ball bearing of the original equipment are within ± 15% respectively.

[0042] By increasing the rotation speed of the bearing, the volume of the grease in the simulation nuclear power plant grease identification simulation bench relative to the original equipment using the grease of the nuclear power plant can be reduced while reducing the size of the bearing and the overall size of the simulation bench, while ensuring that the oil replenishment period and the viscosity ratio of the simulation nuclear power plant grease identification simulation bench are close to those of the original equipment. Therefore, when identifying the grease, the requirements for space, radiation and thermal conditions are reduced, and the difficulty of identification is reduced.

[0043] The simulation bench of the present embodiment is designed to achieve the same working conditions and lubrication conditions as the grease in the original equipment, and the oil replenishment period t and the viscosity ratio k of the grease are used as the main simulation design basis, which are described in detail as follows.

[0044] For the oil replenishment period t:

[0045] If the working life of the grease is shorter than the expected working life of the rolling bearing, the rolling bearing needs to be replenished with grease. The time interval for replenishing the grease depends on many factors, including bearing type and size, rotation speed, working temperature, type of grease, space in the bearing chamber and working environment. SKF defines the period of replenishing the grease, i.e. the oil replenishment period t, as the time during which not less than 99% of the bearings are still fully and reliably lubricated and do not fail due to aging. Therefore, the oil replenishment period t can represent the life of the grease.

[0046] Figure 2 The function relationship between the oil replenishment period t of the grease and the speed coefficient A is shown, where the abscissa is the product of A and Bf, and the ordinate is the oil replenishment period t. Under the condition that the grease has a certain load ratio C / P, the grease has a corresponding oil replenishment period t and A·Bf value.

[0047] where A = n*dm, n is the rotational speed of each bearing in r / min; dm is the average diameter of the bearing in mm, dm = 0.5(d+D), d is the diameter of the inner ring of the bearing in mm, D is the diameter of the outer ring of the bearing in mm. Each bearing is calculated separately, for example, the angular contact ball bearing is compared with the angular contact ball bearing of the original equipment, the original equipment angular contact ball bearing model is 7320BECBM, the average diameter d2 is about 157.5 mm, the rotational speed n2 is 1500 r / min, and the rotational speed coefficient A is 236000 mm*r / min; then the angular contact ball bearing of the simulation bench can be selected by increasing the rotational speed n1 of the pump shaft 50 to 3000 r / min, so that the average inner diameter d1 of the angular contact ball bearing is about 85 mm, and the speed coefficient A is 255000 mm*r / min.

[0048] where Bf is the bearing factor, which depends on the bearing type and the bearing factor of the load condition, and is a correction to the speed coefficient A.

[0049] where the load ratio C / P is related to the shear force of the lubricating grease in each bearing, which is determined by the bearing type.

[0050] From Figure 2 It can be seen that when the bearing type, bearing load condition, and load ratio C / P are determined, the speed coefficient A and the lubricating grease oil replenishment period t are inversely proportional. In other words, when the oil replenishment period t and the load ratio C / P are constant, the greater the rotational speed of the bearing, the smaller the average diameter of the bearing. That is, by increasing the rotational speed, the size of the bearing, i.e. the size of the simulation bench, can be reduced, thereby realizing lubricating grease identification with a smaller simulation device.

[0051] In the original equipment, the bearing size, rotational speed, and load received are constant values, therefore, the lubricating grease in the original equipment has a determined oil replenishment period, which is defined as the oil replenishment period T, and the oil replenishment period T also satisfies the relationship shown in the above Figure 5 .

[0052] For the viscosity ratio k:

[0053] The effectiveness of the lubricating grease depends on the separation of the two surfaces in the rolling contact surface, in order to form a lubricating film that is sufficient to separate the two surfaces, the lubricating grease must maintain a minimum viscosity at the normal working temperature, which is the rated viscosity υ1 that the lubricating grease needs to provide to the lubricated component in the working state. The lubricating condition that the lubricating grease can provide can be evaluated by the viscosity ratio κ, which is the ratio of the actual working viscosity υ to the rated viscosity υ1 that can provide sufficient lubrication.

[0054] The rated viscosity υ1 is a parameter representing the normal working condition of the bearing, and therefore, for a bearing of a certain type, it should have a certain rated viscosity υ1, which can be found in the SKF bearing catalogue, or more accurately, by using the bearing calculator provided by SKF.

[0055] The actual working viscosity υ is a characteristic of the grease, and its value is determined after the type and model of the grease are selected, and can be found in the data provided by the grease manufacturer.

[0056] Figure 3 The function relationship between the rated viscosity υ1 and the average diameter dm of the bearing is shown, and since the viscosity ratio k = υ / υ1, the change of the viscosity ratio k mainly depends on the change of the rated viscosity υ1 of the bearing. From the formula Figure 3 It can be seen that, when the bearing rotational speed n is constant, the average diameter dm of the bearing is inversely proportional to the rated viscosity υ1; and when the average diameter dm of the bearing is constant, the bearing rotational speed n is inversely proportional to the rated viscosity υ1.

[0057] Therefore, while increasing the bearing rotational speed n and reducing the average diameter dm of the bearing, it is possible to maintain a rated viscosity υ1 in the simulation bench similar to that in the original equipment, i.e., to achieve the same lubrication state.

[0058] Preferably, to make the nuclear power plant grease identification simulation bench have a similar rated viscosity υ1 relative to the original equipment, the speed coefficient A of the nuclear power plant grease identification simulation bench is set to have an error value within ±15% relative to the original equipment.

[0059] In summary, the oil replenishment period t and the viscosity ratio k are both reduced with the increase of the bearing rotational speed n and the increase of the average diameter dm of the bearing, and therefore, by increasing the bearing rotational speed n and reducing the average diameter dm of the bearing, it is possible to maintain the oil replenishment period t and the viscosity ratio k of the grease in the simulation bench similar to those in the original equipment. Thus, the grease can be accurately identified.

[0060] In one embodiment, the simulation bench further comprises a heating device for heating the pump shaft and the bearings and the like on the pump shaft to simulate the actual operating conditions of the original equipment. Optionally, the heating device can be a heating furnace, and the pump shaft together with the bearings and the like thereon are placed in the heating furnace (such as a LOCA furnace). The driving device is located outside the heating furnace, and the driving device drives the pump shaft to rotate through the connecting shaft and the like penetrating the heating furnace.

[0061] It should be noted that below 70°C, the service life of the grease is basically independent of the temperature, i.e., below 70°C, the oil replenishment period t of the grease is independent of the working temperature. Figure 2 and Figure 3 are data measured at 70°C, and below 70°C, the data can still be referred to.Figure 2 and Figure 3 .

[0062] In an optional embodiment, the heating device is used to heat the pump shaft and the bearing, so that the pump shaft, the bearing and the lubricating grease to be identified are tested at 50-60℃. Optionally, 50℃.

[0063] Specifically, the average diameter of the deep groove ball bearing 20, the roller bearing 30 and the angular contact ball bearing 40, and the rotating speed of the pump shaft 50 are determined by formula (1);

[0064] n1d1=Kn2d2 (1)

[0065] Wherein:

[0066] n1 is the rotating speed of the deep groove ball bearing 20, the roller bearing 30 and the angular contact ball bearing 40, r / min;

[0067] d1 is the average diameter of the deep groove ball bearing 20, the roller bearing 30 or the angular contact ball bearing 40, mm;

[0068] K is a constant, and the value range is 0.85≤K≤1.15;

[0069] n2 is the rotating speed of the deep groove ball bearing of the original equipment, the roller bearing of the original equipment and the angular contact ball bearing of the original equipment, r / min;

[0070] d2 is the average diameter of the deep groove ball bearing of the original equipment, the roller bearing of the original equipment or the angular contact ball bearing of the original equipment, mm;

[0071] The lubricating grease oiling period t and the viscosity ratio k of the deep groove ball bearing 20, the roller bearing 30 and the angular contact ball bearing 40 determined by formula (1) are calculated, and if the error value of the lubricating grease oiling period t or the viscosity ratio k of the deep groove ball bearing 20, the roller bearing 30 and the angular contact ball bearing 40 relative to the original equipment is greater than 15%, the parameters of formula (1) are adjusted again for determination, that is, the selection of the type, size, rotating speed and the like of the bearing is performed again, until the error value of the lubricating grease oiling period t and the viscosity ratio k of the simulation bench relative to the oiling period t and the viscosity ratio k of the original equipment is within ±15%.

[0072] Preferably, the grease replenishment cycle t and viscosity ratio k of the simulated test bench are both slightly smaller than those of the original equipment, and greater than or equal to 85% of those of the original equipment. This is because the grease replenishment cycle t and viscosity ratio k of the simulated test bench are smaller than those of the original equipment, indicating a more severe working environment for the grease in the simulated test bench. Therefore, if the grease remains effective within a specified time in the simulated test bench, it is likely that the grease will also remain effective for a sufficient period in the original equipment, providing a more conservative verification of the grease's effectiveness.

[0073] The dimensions of the bearing housing 10 and the pump shaft 50 are set according to the deep groove ball bearing 20, the roller bearing 30, and the angular contact ball bearing 40, so that the bearing housing 10 and the pump shaft 50 form a tight fit with the deep groove ball bearing 20, the roller bearing 30, and the angular contact ball bearing 40. Preferably, the bearing housing 10 is made of a material similar to that of the original equipment, which may include, but is not limited to, carbon steel; the pump shaft 50 is made of a material similar to that of the original equipment, which may include, but is not limited to, stainless steel.

[0074] For example Figure 5 As shown, in some embodiments, the bearing body 10 may be provided with an exhaust chamber 16, which connects to the first bearing chamber 11, the second bearing chamber 12, and the third bearing chamber 13. The pump shaft 50 is a hollow structure with a through axial chamber in the middle, and the pump shaft 50 is also provided with several radially arranged first through holes 51 that connect to the aforementioned axial chamber. The first through holes 51 also connect to the exhaust chamber 16, which are used to allow steam to enter the exhaust chamber from the pump shaft 50 through the first through holes 51 and then further enter the first bearing chamber 11, the second bearing chamber 12, and the third bearing chamber 13, so that each bearing operates under high temperature and high pressure.

[0075] In some embodiments, the bearing body 10 may be provided with a first threaded hole 17 and a plug 171. The first threaded hole 17 connects the exhaust chamber 16 to the outside, and the plug 171 is detachably connected to the first threaded hole 17 by means of a threaded engagement, for discharging condensate generated by steam in the exhaust chamber 16. In some embodiments, the bearing body 10 may be provided with a plurality of circumferentially arranged second threaded holes 18 on the side near the deep groove ball bearing 20 for connecting parts to pass through, so that the simulation platform is fixedly connected to the LOCA furnace flange, and the LOCA furnace flange provides support for the fixation of the bearing body 10.

[0076] In some embodiments, the nuclear power plant grease testing simulation bench may also include a bushing 60. The bushing 60 is fitted around a plurality of first through holes 51 on the outside of the pump shaft 50. The bushing 60 has a second through hole 61 connecting the plurality of first through holes 51 and the exhaust chamber 16. The bushing is used to protect the pump shaft 50. On both sides of the bushing 60, there is a radially outwardly extending and annular disc 62. A gap is left between the disc 62 and the inner wall of the bearing body 10 to uniformly guide steam to the second bearing chamber 12 and the third bearing chamber 13. The disc 62 can also be dynamically balanced by grinding or adding weight to its own structure. Preferably, the bushing 60 may be made of materials including but not limited to carbon steel.

[0077] like Figure 5 As shown, the second bearing chamber 12 is provided with at least two radially corresponding first fixing seats 121. The first fixing seats 121 are suspended relative to the bearing body 10, and there is a certain gap between them. The first fixing seats 121 are provided with positioning holes 1211. The two first fixing seats 121 are arranged opposite each other along the diametrical direction to increase radial support for the pump shaft from the radially opposite sides of the pump shaft and maintain axial stability.

[0078] In some embodiments, the nuclear power plant grease testing simulation bench may further include a radial force loading assembly 14 for applying radial pressure to the roller bearing 30 along the pump shaft 50. In some embodiments, the radial force loading assembly 14 may include a clamping member 141, a positioning post 142, a first elastic member 143, and a second fixing seat 144. The second fixing seat 144 passes through the surface of the bearing body 10 and has an extension parallel to the surface of the bearing body 10. The extension and the surface of the bearing body 10 it covers have mutually mating through holes. Fasteners are inserted through these through holes to fix the second fixing seat 144 to the surface of the bearing body 10. One end of the second fixing seat 144 is sleeved on the first fixing seat, and the other end is sleeved on the clamping member 141 and threadedly connected to it. Both ends of the first elastic member 143 abut against the first fixing seat 121 and the clamping member 141. The two ends of the positioning pin 142 are respectively inserted into the clamping member 141 and the first fixed seat 121, and are used to fix the clamping member 141 and the first fixed seat 121 on the same vertical center line. Specifically, the radial load provided by the radial force loading assembly 14 to the second bearing chamber 12 can be changed by changing the stiffness of the first elastic member 143 or the screwing depth of the clamping member 141 relative to the second fixed seat 144. The magnitude of the radial load mainly affects the life of the deep groove ball bearing 20, the roller bearing 30 and the angular contact ball bearing 40. By adjusting the magnitude of the radial load, the life of the deep groove ball bearing 20, the roller bearing 30 and the angular contact ball bearing 40 on the nuclear power plant grease testing simulation bench can be made close to that of the original equipment.

[0079] The nuclear power plant grease identification simulation bench in some embodiments can further include two positioning baffles 70 respectively arranged on the two axial sides of the second bearing chamber 12, for preventing the second bearing chamber 12 from falling off during installation. Preferably, the baffle 70 can be integrally formed with the shaft sleeve 60.

[0080] As shown in Figure 4 , Figure 5 and Figure 6 , in some embodiments, the first bearing chamber 11 can form a first oil seal structure 111 and a second oil seal structure 112 on both sides of the deep groove ball bearing 20, respectively, for preventing leakage of the lubricating grease. The second bearing chamber 12 can form a third oil seal structure 122 and a fourth oil seal structure 123 on both sides of the roller bearing 30, respectively, for preventing leakage of the lubricating grease. The third bearing chamber 13 can form a fifth oil seal structure 131 and a sixth oil seal structure 132 on both sides of the angular contact ball bearing 40, respectively, for preventing leakage of the lubricating grease. Preferably, the first oil seal structure 111, the second oil seal structure 112, the third oil seal structure 122, the fourth oil seal structure 123, the fifth oil seal structure 131 and the sixth oil seal structure 132 are arranged in accordance with the corresponding oil seal structures on both sides of the bearings of the original equipment in a proportionally reduced manner. Preferably, the first oil seal structure 111, the second oil seal structure 112, the third oil seal structure 122, the fourth oil seal structure 123, the fifth oil seal structure 131 and the sixth oil seal structure 132 are made of similar materials as the original equipment, which can include but not limited to carbon steel.

[0081] As shown in Figure 6 , in some embodiments, the angular contact ball bearing 40 can be provided in two numbers, with a spacing ring 80 arranged between the two angular contact ball bearings 40, and the inner rings of the two angular contact ball bearings 40 abutting the inner side of the spacing ring 80. The force on the angular contact ball bearing 40 is realized by applying an axial force to the outer ring of one of the angular contact ball bearings 40, specifically, by applying an axial thrust to the outer ring of the angular contact ball bearing 40 that is away from the roller bearing located in the middle.

[0082] The nuclear power plant grease identification simulation bench in some embodiments can further include an axial force loading assembly 15 for applying pressure to the angular contact ball bearing 40 along the axial direction of the pump shaft 50. As shown in Figure 6As shown, the axial force loading assembly 15 can include a third fixed seat 151, an elastic piece baffle 152, a second elastic piece 153, and an elastic piece base 154 in some embodiments. The third fixed seat 151 is fixedly connected to the axial outer surface of the third bearing chamber 13, and the elastic piece baffle 152 is arranged inside the third fixed seat 151. The elastic piece baffle 152, the second elastic piece 153, the elastic piece base 154, the sixth oil seal structure 132, and the angular contact ball bearing 40 are sequentially arranged along the axial direction of the pump shaft 50 and abut with each other. The elastic piece base 154 is fixed to the side surface of the sixth oil seal structure 132. Specifically, the thickness of the elastic piece baffle 152 can be changed to change the axial load provided by the axial force loading assembly 15 to the third bearing chamber 13. The size of the axial load mainly affects the service life of the angular contact ball bearing 40. By adjusting the size of the axial load, the service life of the angular contact ball bearing 40 on the nuclear power plant grease identification simulation bench can be close to that of the original equipment.

[0083] The third bearing chamber 13 can be provided with a cooling water chamber 133 in some embodiments for perfusing cooling water to cool the bearing. The third bearing chamber 13 is also provided with a temperature probe hole 134 for accommodating a thermocouple to monitor the bearing temperature in real time.

[0084] To make the purpose, technical solutions and technical effects of the present application clearer, the following will take the CPR1000 pressurized water reactor unit as an example, which is the original equipment using grease in a nuclear power plant. The motor of the original equipment is provided with a deep groove ball bearing of model 6326M / C3 and a roller bearing of model NU 324ECM. The pump of the original equipment is provided with a roller bearing of model NU 321ECJ and an angular contact ball bearing of model 7320BECBM. According to the embodiment of the present application, a nuclear power plant grease identification simulation bench for the original equipment is designed. The bearing data of the original equipment is listed in Table 1.

[0085] Table 1: Bearing data of the original equipment

[0086]

[0087] Among them, the viscosity ratio and the grease replenishment period of the roller bearing of the pump are smaller than those of the roller bearing of the motor, so only the simulation test of the roller bearing of the pump is needed.

[0088] The speed n1 of the nuclear power plant grease identification simulation bench is increased to 3000r / min. According to the average diameter d1 of the nuclear power plant grease identification simulation bench selected according to formula (1), the appropriate model is selected, and the finally selected bearing data is listed in Table 2.

[0089] Table 2: Bearing data of the nuclear power plant grease identification simulation bench

[0090]

[0091]

[0092] It can be understood that the above embodiments only express the preferred embodiments of the present application, which are described in a more specific and detailed manner, but cannot be understood as a limitation to the patent scope of the present application; it should be pointed out that the above technical features can be freely combined without departing from the concept of the present application for those skilled in the art, and a number of modifications and improvements can be made, which all belong to the protection scope of the present application; therefore, any equivalent transformation and modification made to the patent claim scope of the present application shall belong to the coverage of the patent claim of the present application.

Claims

1. A simulation test bench for identifying nuclear power plant lubricating grease, characterized in that, The nuclear power plant grease identification simulation bench includes a bearing body (10), a deep groove ball bearing (20), a roller bearing (30), an angular contact ball bearing (40), a pump shaft (50), and a drive device; The bearing body (10) is sleeved on the pump shaft (50). The bearing body (10) is provided with a first bearing chamber (11) for accommodating the deep groove ball bearing (20), a second bearing chamber (12) for accommodating the roller bearing (30), and a third bearing chamber (13) for accommodating the angular contact ball bearing (40). The drive device is used to drive the pump shaft together with the bearing body (10), deep groove ball bearing (20), roller bearing (30), and angular contact ball bearing (40) thereon to rotate at a speed n1, where the speed n1 is greater than the rotational speed of the pump shaft in the original equipment; the grease replenishment cycle t and viscosity ratio k of the deep groove ball bearing (20), the roller bearing (30), and the angular contact ball bearing (40) are within ±15% of the grease replenishment cycle t and viscosity ratio k of the deep groove ball bearing, the roller bearing, and the angular contact ball bearing in the original equipment. The deep groove ball bearing (20), roller bearing (30), and angular contact ball bearing (40) are arranged sequentially along the axial direction of the pump shaft (50); the nuclear power plant grease identification simulation bench also includes a radial force loading assembly (14) for applying pressure to the roller bearing (30) on one radial side of the pump shaft (50); The first bearing chamber (11) forms a first oil seal structure (111) and a second oil seal structure (112) on both sides of the deep groove ball bearing (20); the second bearing chamber (12) forms a third oil seal structure (122) and a fourth oil seal structure (123) on both sides of the roller bearing (30); the third bearing chamber (13) forms a fifth oil seal structure (131) and a sixth oil seal structure (132) on both sides of the angular contact ball bearing (40). The nuclear power plant grease identification simulation bench also includes an axial force loading assembly (15) for applying pressure to the angular contact ball bearing (40) along the pump shaft (50).

2. The nuclear power plant lubricating grease identification simulation bench according to claim 1, characterized in that, The average diameters of the deep groove ball bearing (20), the roller bearing (30) and the angular contact ball bearing (40), as well as the rotational speed of the pump shaft (50), are determined using formula (1). n1d1=Kn2d2(1) in: n1 is the rotational speed (r / min) of the deep groove ball bearing (20), the roller bearing (30) and the angular contact ball bearing (40); d1 is the average diameter of the deep groove ball bearing (20), the roller bearing (30), or the angular contact ball bearing (40), in mm; K is a constant, with a value range of 0.85 ≤ K ≤ 1.15; n2 is the rotational speed (r / min) of the deep groove ball bearing, the roller bearing, and the angular contact ball bearing of the original equipment. d2 is the average diameter (mm) of the deep groove ball bearing, the roller bearing, or the angular contact ball bearing of the original equipment.

3. The nuclear power plant lubricating grease identification simulation bench according to claim 2, characterized in that, The ratios of the grease replenishment cycle t and viscosity ratio k of the deep groove ball bearing (20), the roller bearing (30), and the angular contact ball bearing (40) to the grease replenishment cycle and viscosity ratio of the original equipment's deep groove ball bearing, the original equipment's roller bearing, and the original equipment's angular contact ball bearing are respectively greater than or equal to 0.85 and less than 1.

4. The nuclear power plant lubricating grease identification simulation bench according to claim 1, characterized in that, The second bearing chamber (12) is provided with at least two radially corresponding first fixing seats (121), and the first fixing seats (121) are provided with positioning holes (1211). The radial force loading assembly (14) includes a clamping member (141), a positioning post (142), a first elastic member (143), and a second fixing seat (144); one end of the positioning post (142) is inserted into the positioning hole (1211), and the other end is threadedly connected to the clamping member (141); the first elastic member (143) abuts against the first fixing seat (121) and the clamping member (141); the second fixing seat (144) is sleeved on the first fixing seat (121) and the clamping member (141).

5. The nuclear power plant lubricating grease identification simulation bench according to claim 1, characterized in that, The number of angular contact ball bearings (40) is set to two, and a spacer ring (80) is provided between the two angular contact ball bearings (40). The inner rings of the two angular contact ball bearings (40) respectively abut against the inner side of the spacer ring (80); The axial force loading assembly (15) includes a third fixed seat (151), an elastic baffle (152), a second elastic element (153), and an elastic element base (154). The third fixed seat (151) is fixedly connected to the outer surface of the third bearing chamber (13). The elastic baffle (152) is disposed inside the third fixed seat (151). The elastic baffle (152), the second elastic element (153), the elastic element base (154), the sixth oil seal structure (132), and the angular contact ball bearing (40) are arranged sequentially along the axial direction of the pump shaft (50) and abut against each other.

6. The nuclear power plant lubricating grease testing simulation bench according to any one of claims 1 to 5, characterized in that, The bearing body (10) is provided with an exhaust chamber (16), which is connected to the first bearing chamber (11), the second bearing chamber (12) and the third bearing chamber (13); the pump shaft (50) is an axially through hollow structure, and the pump shaft (50) is provided with a plurality of first through holes (51) that penetrate to its inner and outer circumferential surfaces, which are connected to the exhaust chamber (16). The bearing body (10) is provided with a first threaded hole (17) and a plug (171). The first threaded hole (17) connects the exhaust chamber (16) and the outside. The plug (171) is detachably connected to the first threaded hole (17).

7. The nuclear power plant grease testing simulation bench according to claim 6, characterized in that, The nuclear power plant grease identification simulation test bench also includes a bushing (60), which is sleeved on the outside of several first through holes (51) of the pump shaft (50). The bushing (60) is provided with a second through hole (61) connecting several first through holes (51) and the exhaust chamber (16). A disc (62) is provided on both sides of the bushing (60) at several second through holes (61), and a gap is left between the disc (62) and the inner wall of the bearing body (10).

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