Steam turbine bearing box adopting spherical bearing
Through the spherical bearing design and hydraulic damping effect, combined with adjustment of adjustment bolts and support plates, the problem of front bearing box lifting during thermal expansion of the turbine is solved, the stable operation and long life of the bearing are achieved, and the safety and stability of the turbine are ensured.
Patent Information
- Application Number
- CN202422982239.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-04
- Publication Date
- 2025-08-08
- Estimated Expiration
- 2034-12-04
AI Technical Summary
During the thermal expansion process of existing turbines, the connection between the front bearing box and the cylinder block is prone to be raised, resulting in excessive bearing temperature and wear of alloys, which cannot reach full load operation.
The spherical bearing design is adopted, combining the hydraulic damping effect and the centering function of spherical bearings. By adjusting the bolts and support plates, the bearing box is consistent with the center line of the cylinder block, the guide long keys are set and the centering spherical pads are adjusted to limit the movement of the bearing box, ensuring the free expansion of the bearing box and the cylinder block.
It effectively suppresses rotor vibration, ensures safe and stable start-up of the turbine and long-term operation, extends the service life of the bearing, avoids local contact on the surface of the bearing alloy, and achieves safe and stable operation of the unit.
Smart Images
Figure CN223203109U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of steam turbine bearings, and more specifically, to a steam turbine bearing box using a spherical bearing. Background Art
[0002] During turbine startup, shutdown, and operation, the cylinder temperature fluctuates significantly, causing it to expand or contract in length, width, and height. To ensure the cylinder can freely expand in a directional manner and maintain alignment with the rotor center, and to avoid undue stress, vibration, and other problems caused by poor expansion or misalignment, a pin system is required. The front bearing box in the turbine is an important component of the pin system.
[0003] In the prior art, the front bearing box is connected to the turbine cylinder body by connecting screws, and the front bearing box is supported on the plane of the bearing box support. The front bearing box can be expanded and contracted together with the cylinder body through connecting bolts on the bearing box support to achieve free expansion. However, during the thermal expansion process of the unit, as the temperature and load of the unit increase, the pressure plate and the bearing box support surface cannot move forward in parallel and are tilted, which will cause local contact of the bearing at this position, resulting in excessive bearing temperature and even alloy wear and fall off. The unit cannot increase the load and cannot reach full load operation. Utility Model Content
[0004] In order to overcome the above-mentioned defects of the prior art, the utility model provides a steam turbine bearing box using a spherical bearing.
[0005] To achieve the above-mentioned object, the present invention provides the following technical solution: a steam turbine bearing box using a spherical bearing, comprising a front bearing box, the front bearing box being mounted above a bearing box support, the bearing box support being connected to a cylinder body of the steam turbine, a thrust bearing and a spherical bearing being sequentially arranged inside the front bearing box toward the cylinder body, the outer side surface of the spherical bearing being an elliptical surface, and an annular oil storage groove being provided on the outer side surface of the spherical bearing along the direction of rotation, a hydraulic passage being provided inside the front bearing box and communicating with the outer side surfaces of the spherical bearing and the thrust bearing;
[0006] The bearing box support is located at the bottom and both sides of the front bearing box, and the longitudinal guide bosses on both sides are connected to the cylinder body through connecting cat claws to provide longitudinal support force. The support plate and the lower half of the bearing box of the front bearing box are sequentially arranged above the bearing box support, and are connected by gland bolts arranged at the four corners above the lower half of the bearing box;
[0007] The front bearing box is provided with bearing box connecting ears on both sides, which are connected to the cylinder body through screws;
[0008] Adjustment bolts are provided on both sides of the support plate in a horizontal direction perpendicular to the axial direction of the front bearing box. There are four adjustment bolts, which are fixed above the bearing box support.
[0009] As a further preference of the present invention, adjustment and centering spherical pads are provided on both sides of the cylinder bearing box support. The adjustment and centering spherical pads are threadedly connected to the cylinder body and arranged on the left and right sides of the longitudinal guide boss of the bearing box support to limit the lateral movement of the bearing box and ensure the axial free expansion of the front bearing box and the cylinder body.
[0010] As a further preference of the present invention, the cylinder body is fixed with a long guide key, which passes through the bearing box axially and is slidably connected to the front bearing box, and is located between the support plate and the lower half of the bearing box, thereby increasing the guide support force and avoiding expansion and displacement.
[0011] As a further preference of the present invention, an expansion scale is fixed on the bearing box support, and an expansion pointer is fixed on the bearing box connecting ear. The expansion pointer is located above the expansion scale and is clearance-matched with it for measuring the expansion amount and for monitoring to avoid danger caused by excessive expansion.
[0012] As a further preferred embodiment of the present invention, the gland bolt and the washer are spaced 0.10-0.15 mm apart to avoid expansion damage.
[0013] As a further preferred embodiment of the present invention, the key clearance between the guide long key and the guide key is less than 0.02 mm, thereby ensuring the guiding accuracy.
[0014] As a further preference of the present invention, an air duct hole is opened on one side of the process hole. The setting of the process hole is convenient for processing. After the partition is installed, the process hole is blocked and air is introduced through the air duct hole.
[0015] Technical effects and advantages of the utility model:
[0016] 1. By adjusting the bolts, the center lines of the bearing box and the cylinder body are adjusted to be consistent and the centrifugal force of the guide key is ensured. The height of the support plate adjustment pad is adjusted to make the center height of the bearing box consistent with the center height of the cylinder body. The bearing box support surface and the gland bolts at the four corners are arranged at a relatively far distance, which can effectively solve the problem of the front bearing box moving forward and then tilting due to thermal expansion of the unit.
[0017] 2. Adjustment and centering spherical pads are installed in the expansion direction of the cylinder body and the bearing box. They are arranged on the left and right sides of the longitudinal guide boss of the bearing box support to limit the lateral movement of the bearing box and ensure the free axial expansion of the front bearing box and the cylinder body. The modified bearing body and the bearing box are installed with spherical positioning. The spherical bearing has a good self-aligning function, which avoids local contact between the bearing alloy surface and the shaft neck. The hydraulic damping effect effectively suppresses the vibration amplitude of the rotor during operation, ensuring safe and smooth startup and long-term continuous operation of the turbine. It is easy to disassemble and assemble, and effectively extends the service life of the bearing. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 The utility model is a structural schematic diagram of a steam turbine bearing box using a spherical bearing.
[0019] Figure 2 The utility model is a side view of a steam turbine bearing box using a spherical bearing.
[0020] Figure 3 The utility model is a top view of a steam turbine bearing box using a spherical bearing.
[0021] Figure 4 for Figure 3 Schematic diagram of the connection between the bearing box and the cylinder body at D in the middle.
[0022] Figure 5 for Figure 1 Cross-sectional view at AA in the middle.
[0023] Figure 6 for Figure 2 Schematic diagram of the structure at point C in the middle.
[0024] Figure 7 for Figure 2 Schematic diagram of the structure at point B in the middle.
[0025] The accompanying drawings are marked as follows: 1. thrust bearing; 2. spherical bearing; 3. front bearing box; 4. bearing box support; 5. guide long key; 6. support plate; 7. adjusting bolt; 8. gland bolt; 9. adjusting centering spherical pad; 10. cylinder body; 11. connecting cat claw; 201. oil storage tank; 202. hydraulic passage; 301. bearing box connecting ear; 302. bearing box lower half; 303. expansion scale. 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 embodiments described 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 making creative efforts are within the scope of protection of the present invention.
[0027] See attached Figure 1-7 As shown, a steam turbine bearing housing using a spherical bearing includes a front bearing housing 3, which is mounted above a bearing housing support 4. The bearing housing support 4 is connected to the cylinder body 10 of the steam turbine. A thrust bearing 1 and a spherical bearing 2 are sequentially arranged inside the front bearing housing 3, facing the cylinder body 10. The outer surface of the spherical bearing 2 is an elliptical surface, and an annular oil storage groove 201 is provided on the outer surface of the spherical bearing 2 along the direction of rotation. A hydraulic passage 202 is provided in the front bearing housing 3, communicating with the outer surfaces of the spherical bearing 2 and the outer surface of the thrust bearing 1.
[0028] During the operation of the present invention, a spherical bearing 2 with a hydraulic damping effect is used. The bearing body and the bearing housing are mounted spherically for positioning, and the spherical surface is provided with an oil reservoir 201 for lubrication and damping. The elliptical surface increases the bearing width, improving the bearing's load-bearing capacity. The spherical bearing 2 has a good self-aligning function, with a certain gap left at the top. When the unit undergoes thermal expansion, the damping spherical bearing 2 adjusts itself with the main shaft, avoiding local contact between the bearing alloy surface and the journal, ensuring that the bearing temperature during the unit's operation is within the normal operating range to extend its service life. Because the spherical bearing 2 has a hydraulic damping effect, it can more effectively suppress the vibration amplitude of the rotor during operation, ensuring safe and smooth startup of the turbine and long-term continuous operation, and is easy to assemble and disassemble.
[0029] like Figure 1-3 and Figure 6 As shown, in an embodiment of the present utility model, the bearing box support 4 is located at the bottom and both sides of the front bearing box 3, and the longitudinal guide bosses on both sides are connected to the cylinder body 10 through connecting cat claws 11 to provide longitudinal support force. The support plate 6 and the bearing box lower half 302 of the front bearing box 3 are arranged in sequence above the bearing box support 4, and are connected by pressure cover bolts 8 arranged at the four corners above the bearing box lower half 302; the support plate 6 is provided on both sides with adjustment bolts 7 perpendicular to the axial direction of the front bearing box 3 in the horizontal direction, and there are four adjustment bolts 7, which are fixed above the bearing box support 4. The setting of the bearing box support 4 is used to transmit the expansion force of the cylinder body 10 to the bearing box lower half 302.
[0030] like Figure 4 As shown, in the embodiment of the present utility model, bearing box connecting ears 301 are provided on both sides of the front bearing box 3, which are connected to the cylinder body 10 through screws and are used to transmit the expansion axial force of the upper cylinder body 10;
[0031] like Figure 5As shown, in the embodiment of the present utility model, adjustment and centering spherical pads 9 are provided on both sides of the cylinder body 10 bearing box support 4. The adjustment and centering spherical pads 9 are threadedly connected to the cylinder body 10 and arranged on the left and right sides of the longitudinal guide boss of the bearing box support 4. During the operation of the present utility model, the position of the cylinder body 10 bearing box support 4 is adjusted by threading to limit the lateral movement of the bearing box and ensure the axial free expansion of the front bearing box 3 and the cylinder body.
[0032] like Figure 2 and Figure 7 As shown, in an embodiment of the present utility model, the cylinder body is fixed with a long guide key 5, and the long guide key 5 passes through the bearing box axially and is slidably connected to the front bearing box 3, and is located between the support plate 6 and the lower half 302 of the bearing box. The key clearance of the long guide key 5 is less than 0.02mm, which ensures the guiding accuracy and increases the support area. By adjusting the centering lateral positioning and axial guiding structure, the guiding support force is increased to avoid expansion and displacement.
[0033] During operation, the bearing housing and cylinder block 10 are aligned by adjusting bolts 7 to ensure proper centering of the guide key. The height of the support plate 6 is adjusted to align the bearing housing center height with the cylinder block center height. Gland bolts 8 are located at the four corners of the bearing housing lower half 302 and support plate 6, which are spaced far apart. This effectively prevents the front bearing housing 3 from tilting forward due to thermal expansion.
[0034] like Figure 3 As shown, in the embodiment of the present utility model, an expansion scale 303 is fixed on the bearing box support 4, and an expansion pointer is fixed on the bearing box connecting ear 301. The expansion pointer is located above the expansion scale 303 and is clearance-matched with it, and is used to measure the expansion amount and to monitor and avoid the danger of excessive expansion.
[0035] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.
Claims
1. A steam turbine bearing housing using a spherical bearing, comprising a front bearing housing mounted above a bearing housing support, wherein the bearing housing support is connected to a cylinder body of the steam turbine, characterized in that: A thrust bearing and a spherical bearing are sequentially arranged inside the front bearing box toward the cylinder body. The outer surface of the spherical bearing is an elliptical surface, and an annular oil storage groove is provided on the outer surface of the spherical bearing along the direction of rotation. A hydraulic passage is provided in the front bearing box to communicate with the outer surfaces of the spherical bearing and the thrust bearing. The bearing box support is located at the bottom and both sides of the front bearing box, and the longitudinal guide bosses on both sides are connected to the cylinder body through connecting cat claws. A support plate and the lower half of the bearing box of the front bearing box are sequentially arranged above the bearing box support, and are connected by gland bolts arranged at the four corners above the lower half of the bearing box; The front bearing box is provided with bearing box connecting ears on both sides, which are connected to the cylinder body through screws; Adjustment bolts are provided on both sides of the support plate in a horizontal direction perpendicular to the axial direction of the front bearing box. There are four adjustment bolts, which are fixed above the bearing box support.
2. A steam turbine bearing box using a spherical bearing according to claim 1, characterized in that: Adjustment and centering spherical pads are provided on both sides of the cylinder bearing box support, and the adjustment and centering spherical pads are threadedly connected to the cylinder.
3. The steam turbine bearing box using a spherical bearing according to claim 1, characterized in that: A long guide key is fixed to the cylinder body. The long guide key passes through the bearing box axially and is slidably connected to the front bearing box, and is located between the support plate and the lower half of the bearing box.
4. The steam turbine bearing housing using a spherical bearing according to claim 1, characterized in that: An expansion scale is fixed on the bearing box support, and an expansion pointer is fixed on the bearing box connecting ear. The expansion pointer is located above the expansion scale and is clearance-matched with the expansion scale.
5. The steam turbine bearing housing using a spherical bearing according to claim 1, characterized in that: The gap between the gland bolt and the washer is 0.10-0.15 mm.
6. The steam turbine bearing housing using a spherical bearing according to claim 3, characterized in that: The key clearance of the guide long key is less than 0.02 mm.