Squeeze film damper for motor of centrifugal compressor and assembly structure of squeeze film damper

Abstract

The invention relates to a squeeze film damper for a motor of a centrifugal compressor and an assembly structure of the squeeze film damper. The squeeze film damper is characterized by comprising a squirrel cage shell, a pivotal bearing, a squeeze film damper body, a bearing retainer, a lubricating oil duct module and a sealing module. The motor end cover is provided with the auxiliary oil duct unit, the auxiliary oil duct unit and the motor end cover form split type double oil inlet holes, the two oil inlet holes are used for oiling and lubricating the side face and the outer contour of the slewing bearing respectively, and the structure of the auxiliary oil duct unit can facilitate cleaning and follow-up maintenance of an oil duct. In order to ensure the installation of the squeeze film damper on the motor end cover, the newly designed squeeze film damper is provided with a U-shaped notch, so that interference can be avoided; in order to avoid interference between the extrusion oil film damper and an outer sealing bayonet and interference between the extrusion oil film damper and a motor shell, a straight chamfer and an outer arc-shaped groove are arranged on the flange plate. In order to avoid interference between the extrusion oil film damper and the outline of the pivotal bearing, an inner arc-shaped groove is formed in the extrusion oil film damper.

Description

Technical Field

[0001] The invention relates to the technical field of centrifugal compressors, and in particular to a squeeze film damper for a motor of a centrifugal compressor and an assembly structure thereof. Background Art

[0002] The motor structure used in the multi-stage air compressor needs to fully consider the lubrication, shock absorption and sealing effects of the entire motor shaft; firstly, in the lubrication of the motor shaft, the oil channel structure is used to oil the outer contour of the slewing bearing on the one hand, and the side of the slewing bearing on the other hand, and two oil filling ports are used to achieve better lubrication. However, these two oil filling ports are generally directly opened on the same axial oil channel. This structural method is that the oil channel is not easy to clean in the later maintenance, and it is easy to be blocked; Secondly, in the shock absorption effect of the motor shaft, a common treatment method is to install a squeeze film damper at the end of the motor shaft as the main structure for shock absorption; however, the squeeze film damper will affect the new lubrication structure of the motor shaft when installed on the motor shaft. In order to ensure the oil lubrication of the side of the slewing bearing and reduce blockage and facilitate maintenance, the lubrication structure needs to install an auxiliary oil channel unit to form two split oil filling ports. At this time, the installation position of the auxiliary oil channel unit interferes with the installation position of the squeeze film damper. Therefore, a new squeeze film damper is needed to cooperate with a new lubrication module to achieve lubrication and shock absorption of the motor shaft. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a squeeze film damper for the motor of a centrifugal compressor and its assembly structure, which can solve the problem that the conventional integrated lubricating oil channel is difficult to clean and maintain and is easy to clog, and the problem that the new split slewing bearing lubricating oil channel structure interferes with the squeeze film damper during installation when facilitating cleaning and lubrication.

[0004] In order to solve the above technical problems, the technical solution of the present invention is: a squeeze film damper for a motor of a centrifugal compressor, the innovation of which is: comprising a squirrel cage housing; The squirrel cage shell is a hollow cylindrical structure, and the two ends of the squirrel cage shell are opened; a flange is arranged at the outer contour of one end of the squirrel cage shell; the middle part of the squirrel cage shell has a plurality of cage bars, and there are through holes between adjacent cage bars; a plurality of oil return holes are evenly opened on the side wall of the other end of the squirrel cage shell; an outer arc groove is arranged at the junction of the flange and the outer contour of the squirrel cage shell, and a straight chamfer is arranged at the junction of the flange and the inner contour of the end of the squirrel cage shell; a step is arranged between the inner contour of the cage bar area on the squirrel cage shell and the inner contour of the oil return hole area on the squirrel cage shell, and an inner arc groove is arranged at the junction of the corner position of the step and the oil return hole area; The flange is provided with a U-shaped notch for installing the auxiliary oil channel unit.

[0005] A centrifugal compressor motor squeeze film damper assembly structure, comprising a motor shaft, a motor housing and a motor end cover; the motor end cover is arranged at the end of the motor housing by bolt connection, and a motor shaft mounting hole is opened at the center of the motor housing; the outer contour of the end of the motor shaft is installed at the position of the motor shaft mounting hole of the motor end cover through a slewing bearing; its innovation lies in: comprising a slewing bearing, a squeeze film damper, a bearing retainer, a lubricating oil channel module and a sealing module; The motor shaft has a stepped structure, and the outer contour of the motor shaft is provided with a first step surface, a second step surface, a third step surface and a fourth step surface in sequence from the end to the middle position; the end of the motor shaft is provided with a connecting hole, and the end of the motor shaft is connected to the impeller by bolts, and a volute is provided on the outside of the impeller, the inner end surface of the volute is connected to the adapter plate by bolts, and the adapter plate is fixed to the outer end surface of the motor end cover by bolts; The slewing bearing is nested at the third step surface, and bearing retainers are respectively arranged on both sides of the slewing bearing at the third step surface to limit the inner ring of the slewing bearing, and the bearing retainer at the third step surface and close to the second step surface extends to above the second step surface; the second step surface is provided with a thread, and a locking nut is provided on the thread, and the locking nut cooperates with the thread to realize the pressing of the bearing retainer and the slewing bearing on the third step surface; an inner sealing bayonet is provided on the bearing retainer at the third step surface and close to the fourth step surface; The oil return hole area of ​​the squeeze film damper is nested in the outer contour of the slewing bearing, and the cage bar area of ​​the squeeze film damper extends above the second stepped surface of the motor shaft; the flange of the squeeze film damper is locked on the motor end cover by bolts; The lubricating oil passage module is arranged on the motor end cover; the lubricating oil passage module comprises a radial oil passage, an axial oil passage and an auxiliary oil passage unit; the radial oil passage is arranged along the radial direction of the motor end cover, and the axial oil passage is vertically arranged at one end of the radial oil passage; the radial oil passage and the axial oil passage form a T-shaped structure, and one end of the axial oil passage is connected to the end face of the motor end cover; one end of the auxiliary oil passage unit is embedded in the axial oil passage from the end face of the motor end cover; The auxiliary oil channel unit is of L-shaped structure, and an L-shaped oil channel is arranged inside to communicate with the axial oil channel; a first oil inlet is arranged at the bottom end of the auxiliary oil channel unit, and the first oil inlet is located beside the slewing bearing at the motor shaft mounting hole and inside the cage bar position of the squirrel cage shell; a second oil inlet is opened at the bottom end of the axial oil channel, and the second oil inlet is located at the outer ring of the slewing bearing on the motor end cover; an L-shaped connecting block is arranged on the side of the auxiliary oil channel unit, and the L-shaped connecting block extends to the outer side of the motor end cover, and the L-shaped connecting block on the auxiliary oil channel unit is clamped in the U-shaped notch on the flange, and is locked on the outer side of the motor end cover by screws; The sealing module comprises an outer sealing unit and an inner sealing unit; the outer sealing unit comprises an outer annular sealing cover, an outer sealing bayonet and an outer pressure ring; the outer annular sealing cover is locked on the outer side surface of the motor end cover by screws, and a through hole for accommodating the motor shaft to pass through is opened at the center of the outer annular sealing cover; the outer sealing bayonet is arranged at the first stepped surface of the motor shaft; the outer sealing bayonet is located on the inner side of the through hole of the outer annular sealing cover; the outer pressure ring is arranged at the first stepped surface of the motor shaft, and the outer pressure ring and the outer sealing bayonet form an annular groove for accommodating the position of the through hole of the outer annular sealing cover, and the through hole contour of the outer annular sealing cover is embedded in the annular groove; The inner sealing unit comprises an inner annular sealing cover; the inner annular sealing cover is fastened to the inner side surface of the motor end cover by screws, and a circular hole for accommodating the motor shaft to pass through is opened at the center of the inner annular sealing cover; the circular hole contour of the inner annular sealing cover is embedded in the inner sealing bayonet.

[0006] Furthermore, a guide hole for accommodating the motor shaft is opened at the center of the adapter plate, and the guide hole of the adapter plate is located outside the first step surface of the motor shaft; a plurality of oil storage grooves are provided on the inner side wall of the guide hole of the adapter plate, the inner side wall of the shaft hole of the outer annular sealing cover, and the inner side wall of the shaft hole of the inner annular sealing cover.

[0007] The advantages of the present invention are: 1) In the present invention, an auxiliary oil channel unit is arranged on the motor end cover to form a split double oil inlet hole with the motor end cover. The two oil inlet holes are respectively used to lubricate the side and outer contour of the slewing bearing. The structure of the auxiliary oil channel unit can facilitate the cleaning of the oil channel and subsequent maintenance. The auxiliary oil channel unit is convenient for adjusting the distance between the oil inlet and the side of the slewing bearing to provide a better lubrication effect. In addition, the auxiliary oil channel structure is adopted. In order to ensure the installation of the squeeze film damper on the motor end cover, a U-shaped notch is opened on the newly designed squeeze film damper to avoid interference.

[0008] 2) In the present invention, sealing units are arranged on both the inner and outer sides of the motor end cover, and the central contour positions of the inner and outer annular sealing covers adopt independent slot structures. At the same time, an oil storage tank structure is also arranged, and the leaked lubricating oil can be stored in multiple oil storage tanks, thereby ensuring the sealing effect and lubrication effect of the motor shaft during movement, reducing the outflow of lubricating oil, reducing the frequency of refueling of lubricating oil, extending the maintenance cycle, and improving the overall service life of the motor. In addition, in order to avoid interference between the squeeze film damper and the external sealing bayonet and interference with the motor housing, a straight chamfer and an outer arc groove are arranged on the flange; in order to avoid interference between the squeeze film damper and the contour of the slewing bearing, an inner arc groove is arranged on the squeeze film damper. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0010] Figure 1 The present invention is a side view of a squeeze film damper for a motor of a centrifugal compressor.

[0011] Figure 2 The present invention is a front view of a squeeze film damper for a motor of a centrifugal compressor.

[0012] Figure 3 The present invention is a structural diagram of an assembly of a squeeze film damper for a motor of a centrifugal compressor.

[0013] Figure 4 The present invention is a partial enlarged view of the assembly structure of a squeeze film damper for a motor of a centrifugal compressor. DETAILED DESCRIPTION

[0014] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0015] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. 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.

[0016] like Figures 1 to 4 The squeeze film damper for a motor of a centrifugal compressor shown comprises a squirrel cage housing 1 .

[0017] The cage shell 1 is a hollow cylindrical structure, and both ends of the cage shell 1 are opened; a flange 11 is arranged at the outer contour of one end of the cage shell; the middle part of the cage shell 1 has a plurality of cage bars 12, and through holes are formed between adjacent cage bars 12; a plurality of oil return holes 13 are evenly opened on the side wall of the other end of the cage shell 1; an outer arc groove is arranged at the junction of the flange 11 and the outer contour of the cage shell 1, and a straight chamfer is arranged at the junction of the flange 11 and the inner contour of the end of the cage shell 1; a step is arranged between the inner contour of the cage bar area on the cage shell 1 and the inner contour of the oil return hole area on the cage shell 1, and an inner arc groove is arranged at the junction of the corner position of the step and the oil return hole area; The flange 11 is provided with a U-shaped notch 14 for installing the auxiliary oil channel unit.

[0018] A centrifugal compressor motor squeeze film damper assembly structure, comprising a motor shaft 2, a motor housing 3 and a motor end cover 4; the motor end cover 4 is arranged at the end of the motor housing 3 by bolt connection, and a motor shaft mounting hole is opened at the center of the motor housing 3; the end outer contour of the motor shaft 2 is installed at the motor shaft mounting hole position of the motor end cover 4 through a slewing bearing 5; comprising a slewing bearing 5, a squeeze film damper, a bearing retainer 6, a lubricating oil channel module 7 and a sealing module 8; The motor shaft 2 has a stepped structure, and the outer contour of the motor shaft 2 is sequentially provided with a first step surface 21, a second step surface 22, a third step surface 23 and a fourth step surface 24 from the end to the middle position; a connecting hole is provided at the end of the motor shaft 2, and the end of the motor shaft 2 is connected to an impeller 25 by bolts, and a volute 26 is provided on the outer side of the impeller 25, and the inner end surface of the volute 26 is connected to the adapter plate 27 by bolts, and the adapter plate 27 is fixed to the outer end surface of the motor end cover 4 by bolts; The slewing bearing 5 is nested in the third step surface 23, and bearing retainers 6 are respectively arranged on both sides of the slewing bearing 5 at the third step surface 23 to limit the inner ring of the slewing bearing 5, and the bearing retainer 6 at the third step surface 23 and close to the second step surface 22 extends to the top of the second step surface 22; the second step surface 22 is provided with a thread, and a locking nut is provided on the thread, and the locking nut cooperates with the thread to realize the bearing retainer 6 and the slewing bearing 5 being pressed on the third step surface 23; the bearing retainer 6 at the third step surface 23 and close to the fourth step surface 24 is provided with an inner sealing bayonet 61; The oil return hole area of ​​the squeeze film damper is embedded in the outer contour of the slewing bearing 5, and the cage bar area of ​​the squeeze film damper extends above the second step surface 22 of the motor shaft 2; the flange 11 of the squeeze film damper is fastened to the motor end cover 4 by bolts; The lubricating oil passage module 7 is arranged on the motor end cover 4; the lubricating oil passage module 7 includes a radial oil passage 71, an axial oil passage 72 and an auxiliary oil passage unit 73; the radial oil passage 71 is arranged along the radial direction of the motor end cover 4, and the axial oil passage 72 is vertically arranged at one end of the radial oil passage 71; the radial oil passage 71 and the axial oil passage 72 form a T-shaped structure, and one end of the axial oil passage 72 is connected to the end face of the motor end cover; one end of the auxiliary oil passage unit 73 is embedded in the axial oil passage 72 from the end face of the motor end cover 3; The auxiliary oil passage unit 73 is of L-shaped structure, and an L-shaped oil passage is arranged inside to communicate with the axial oil passage 72; a first oil inlet 731 is arranged at the bottom end of the auxiliary oil passage unit 73, and the first oil inlet 731 is located beside the slewing bearing 5 at the motor shaft mounting hole and located on the inner side of the cage bar position of the squirrel cage housing 1; a second oil inlet 732 is opened at the bottom end of the axial oil passage 72, and the second oil inlet 732 is located at the outer ring of the slewing bearing 5 on the motor end cover 4; an L-shaped connecting block is arranged on the side of the auxiliary oil passage unit 73, and the L-shaped connecting block extends to the outer side of the motor end cover 4, and the L-shaped connecting block on the auxiliary oil passage unit 73 is clamped at the U-shaped notch 14 on the flange 11, and is locked on the outer side of the motor end cover 4 by screws; The sealing module 8 includes an outer sealing unit 81 and an inner sealing unit 82; the outer sealing unit 81 includes an outer annular sealing cover 811, an outer sealing bayonet 812 and an outer pressure ring 813; the outer annular sealing cover 811 is screwed on the outer side of the motor end cover 4, and a through hole for accommodating the motor shaft 2 to pass through is opened at the center of the outer annular sealing cover 811; the outer sealing bayonet 812 is arranged at the first step surface 21 of the motor shaft 2; the outer sealing bayonet 812 is located on the inner side of the through hole of the outer annular sealing cover 811; the outer pressure ring 813 is arranged at the first step surface 21 of the motor shaft 2, and the outer pressure ring 813 and the outer sealing bayonet 812 form an annular groove for accommodating the through hole position of the outer annular sealing cover 811, and the through hole contour of the outer annular sealing cover 811 is embedded in the annular groove; The inner sealing unit 82 includes an inner annular sealing cover 821; the inner annular sealing cover 82 is screwed to the inner side of the motor end cover 4, and a circular hole is opened at the center of the inner annular sealing cover 821 to accommodate the motor shaft 2; the circular hole contour of the inner annular sealing cover 821 is embedded in the inner sealing bayonet 61.

[0019] A guide hole for accommodating the motor shaft 2 is opened at the center of the adapter plate 27, and the guide hole of the adapter plate 27 is located outside the first step surface 21 of the motor shaft 2; the inner side wall of the guide hole of the adapter plate 27, the inner side wall of the shaft hole of the outer annular sealing cover 811 and the inner side wall of the shaft hole of the inner annular sealing cover 821 are all provided with a plurality of oil storage grooves.

[0020] The working principle of the present invention is: an auxiliary oil channel unit is arranged on the motor end cover to form a split double oil inlet hole with the motor end cover, and the two oil inlet holes are respectively used to lubricate the side and outer contour of the slewing bearing. The structure of the auxiliary oil channel unit can facilitate the cleaning of the oil channel and subsequent maintenance. The auxiliary oil channel unit is convenient for adjusting the distance between the oil inlet and the side of the slewing bearing to provide a better lubrication effect; in addition, by adopting the auxiliary oil channel structure, in order to ensure the installation of the squeeze film damper on the motor end cover, a U-shaped notch is opened on the newly designed squeeze film damper to avoid interference.

[0021] By arranging sealing units on both the inner and outer sides of the motor end cover, and the central contour positions of the inner and outer annular sealing covers adopt independent slot structures, and an oil storage tank structure is also arranged, the leaked lubricating oil can be stored in multiple oil storage tanks, thereby ensuring the sealing and lubricating effects of the motor shaft during movement, reducing the outflow of lubricating oil, reducing the frequency of refueling of lubricating oil, extending the maintenance cycle, and improving the overall service life of the motor. In addition, in order to avoid interference between the squeeze film damper and the external sealing bayonet and interference with the motor housing, a straight chamfer and an outer arc groove are arranged on the flange; in order to avoid interference between the squeeze film damper and the contour of the slewing bearing, an inner arc groove is arranged on the squeeze film damper.

[0022] Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A squeeze film damper for a motor of a centrifugal compressor, characterized in that: including a squirrel cage housing; The squirrel cage shell is a hollow cylindrical structure, and the two ends of the squirrel cage shell are opened; a flange is arranged at the outer contour of one end of the squirrel cage shell; the middle part of the squirrel cage shell has a plurality of cage bars, and there are through holes between adjacent cage bars; a plurality of oil return holes are evenly opened on the side wall of the other end of the squirrel cage shell; an outer arc groove is arranged at the junction of the flange and the outer contour of the squirrel cage shell, and a straight chamfer is arranged at the junction of the flange and the inner contour of the end of the squirrel cage shell; a step is arranged between the inner contour of the cage bar area on the squirrel cage shell and the inner contour of the oil return hole area on the squirrel cage shell, and an inner arc groove is arranged at the junction of the corner position of the step and the oil return hole area; The flange is provided with a U-shaped notch for installing the auxiliary oil channel unit.

2. A centrifugal compressor motor squeeze film damper assembly structure, comprising a motor shaft, a motor housing and a motor end cover; the motor end cover is arranged at the end of the motor housing by bolt connection, and a motor shaft mounting hole is opened at the center of the motor housing; the outer contour of the end of the motor shaft is installed at the motor shaft mounting hole position of the motor end cover through a slewing bearing; characterized in that: It includes a slewing bearing, a squeeze film damper, a bearing cage, a lubrication oil channel module and a sealing module; The motor shaft has a stepped structure, and the outer contour of the motor shaft is provided with a first step surface, a second step surface, a third step surface and a fourth step surface in sequence from the end to the middle position; the end of the motor shaft is provided with a connecting hole, and the end of the motor shaft is connected to the impeller by bolts, and a volute is provided on the outside of the impeller, the inner end surface of the volute is connected to the adapter plate by bolts, and the adapter plate is fixed to the outer end surface of the motor end cover by bolts; The slewing bearing is nested at the third step surface, and bearing retainers are respectively arranged on both sides of the slewing bearing at the third step surface to limit the inner ring of the slewing bearing, and the bearing retainer at the third step surface and close to the second step surface extends to above the second step surface; the second step surface is provided with a thread, and a locking nut is provided on the thread, and the locking nut cooperates with the thread to realize the pressing of the bearing retainer and the slewing bearing on the third step surface; an inner sealing bayonet is provided on the bearing retainer at the third step surface and close to the fourth step surface; The oil return hole area of ​​the squeeze film damper is nested in the outer contour of the slewing bearing, and the cage bar area of ​​the squeeze film damper extends above the second stepped surface of the motor shaft; the flange of the squeeze film damper is locked on the motor end cover by bolts; The lubricating oil passage module is arranged on the motor end cover; the lubricating oil passage module comprises a radial oil passage, an axial oil passage and an auxiliary oil passage unit; the radial oil passage is arranged along the radial direction of the motor end cover, and the axial oil passage is vertically arranged at one end of the radial oil passage; the radial oil passage and the axial oil passage form a T-shaped structure, and one end of the axial oil passage is connected to the end face of the motor end cover; one end of the auxiliary oil passage unit is embedded in the axial oil passage from the end face of the motor end cover; The auxiliary oil channel unit is of L-shaped structure, and an L-shaped oil channel is arranged inside to communicate with the axial oil channel; a first oil inlet is arranged at the bottom end of the auxiliary oil channel unit, and the first oil inlet is located beside the slewing bearing at the motor shaft mounting hole and inside the cage bar position of the squirrel cage shell; a second oil inlet is opened at the bottom end of the axial oil channel, and the second oil inlet is located at the outer ring of the slewing bearing on the motor end cover; an L-shaped connecting block is arranged on the side of the auxiliary oil channel unit, and the L-shaped connecting block extends to the outer side of the motor end cover, and the L-shaped connecting block on the auxiliary oil channel unit is clamped in the U-shaped notch on the flange, and is locked on the outer side of the motor end cover by screws; The sealing module comprises an outer sealing unit and an inner sealing unit; the outer sealing unit comprises an outer annular sealing cover, an outer sealing bayonet and an outer pressure ring; the outer annular sealing cover is locked on the outer side surface of the motor end cover by screws, and a through hole for accommodating the motor shaft to pass through is opened at the center of the outer annular sealing cover; the outer sealing bayonet is arranged at the first stepped surface of the motor shaft; the outer sealing bayonet is located on the inner side of the through hole of the outer annular sealing cover; the outer pressure ring is arranged at the first stepped surface of the motor shaft, and the outer pressure ring and the outer sealing bayonet form an annular groove for accommodating the position of the through hole of the outer annular sealing cover, and the through hole contour of the outer annular sealing cover is embedded in the annular groove; The inner sealing unit comprises an inner annular sealing cover; the inner annular sealing cover is fastened to the inner side surface of the motor end cover by screws, and a circular hole for accommodating the motor shaft to pass through is opened at the center of the inner annular sealing cover; the circular hole contour of the inner annular sealing cover is embedded in the inner sealing bayonet.

3. The assembly structure of a squeeze film damper for a motor of a centrifugal compressor according to claim 2, characterized in that: A guide hole for accommodating the motor shaft is opened at the center of the adapter plate, and the guide hole of the adapter plate is located outside the first step surface of the motor shaft; the inner side wall of the guide hole of the adapter plate, the inner side wall of the shaft hole of the outer annular sealing cover, and the inner side wall of the shaft hole of the inner annular sealing cover are all provided with a plurality of oil storage grooves.

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