Subcritical transformation unit spherical self-aligning sliding bearing
Patent Information
- Application Number
- CN202610993219.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-07-06
- Publication Date
- 2026-11-03
AI Technical Summary
Existing spherical self-aligning sliding bearings, under the conditions of high load, high linear velocity, and large temperature difference in subcritical retrofit units, suffer from problems such as unreasonable oil wedge design, easy wear of the self-aligning limiting structure, and easy peeling of the Babbitt alloy layer, leading to misalignment between the journal and the bearing bush, increased bearing temperature, and even bearing failure.
A spherical self-aligning sliding bearing was designed, comprising a bearing support, a spherical self-aligning bearing bush, a limiting and positioning assembly, a circulating lubrication and cooling assembly, and a top shaft oil circulation assembly. Through ±3° adaptive swing self-alignment, uniform lubrication and cooling across the entire range, and multiple limiting structures, the journal and bearing bush achieve concentricity and a stable oil film, preventing frictional loss.
When the shaft system is misaligned due to rotor deflection and thermal expansion, the automatic self-alignment keeps the journal and bearing concentric, reduces the bearing temperature by 10-20°C, improves operational stability, avoids uneven loading and local dry friction, adapts to variable load conditions, and ensures that the shaft system vibration is within the acceptable range.
Smart Images
Figure CN123028203A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of bearing technology for thermal power units, specifically to a spherical self-aligning sliding bearing for subcritical retrofitted units. Background Technology
[0002] After a long service life, subcritical thermal power units generally require efficiency improvement, capacity expansion, energy saving, and carbon reduction retrofits. After the retrofits, the rotor span, weight, and operating deflection change, and the original rigid fixed cylindrical bearings are prone to the following problems:
[0003] (1) The static deflection and thermal expansion of the rotor cause the journal and the bearing to be misaligned, resulting in uneven oil film and excessive local pressure, which leads to increased bearing temperature or even bearing failure.
[0004] (2) Uneven thermal expansion of the bearing housing causes the shaft system to shift, and the rigid bearing cannot compensate for this.
[0005] (3) Traditional self-aligning tiles may lose their self-aligning function if the spherical fit is too tight, or cause excessive vibration due to excessive movement if the fit is too loose.
[0006] Existing spherical self-aligning sliding bearings are mostly used in metallurgical roller presses or general machinery. They have not been specifically optimized for subcritical retrofit units with large loads (radial load > 200kN), high linear speeds (journal linear speed > 50m / s), and large temperature differences. They have defects such as unreasonable oil wedge design, easy wear of the self-aligning limiting structure, and easy peeling of the Babbitt alloy layer. Summary of the Invention
[0007] The purpose of this invention is to solve the problems of existing spherical self-aligning sliding bearings for subcritical retrofitted units under high load, high linear velocity, and large temperature difference conditions, such as unreasonable oil wedge design, easy wear of self-aligning limiting structure, and easy peeling of Babbitt alloy layer. The invention provides a spherical self-aligning sliding bearing for subcritical retrofitted units.
[0008] The objective of this invention is achieved as follows: a spherical self-aligning sliding bearing for subcritical retrofit units, comprising a bearing support, a spherical self-aligning bearing bush, a limiting and positioning assembly, a circulating lubrication and cooling assembly, and a top shaft oil circulation assembly;
[0009] The bearing support is used to be installed on the bearing housing. A spherical mounting groove is opened on the inner side wall of the bearing support. The outer side wall of the spherical self-aligning bearing is a spherical curved surface. The spherical self-aligning bearing is installed in the spherical mounting groove with clearance fit, and can achieve ±3° adaptive swing self-alignment relative to the bearing support.
[0010] Two symmetrical oil grooves are evenly distributed on the inner wall of the spherical self-aligning bearing, and oil return channels are provided on the oil grooves.
[0011] A limit positioning component is assembled between the bearing support and the spherical self-aligning bearing bush to limit the circumferential movement and position the spherical self-aligning bearing bush.
[0012] The circulating lubrication and cooling assembly and the top shaft oil circulation assembly are located in the lower half of the spherical self-aligning bearing. The circulating lubrication and cooling assembly is used to achieve uniform lubrication and cooling of the entire inner wall of the spherical self-aligning bearing, and the top shaft oil circulation assembly is used to lift the rotor to a preset height during the unit start-up phase.
[0013] Furthermore, the bearing support is a split 25# steel forged steel component.
[0014] Furthermore, the upper part of the bearing support is provided with mounting flanges with mounting holes on both the left and right sides, and the lower part of the bearing support is provided with positioning stops on both the left and right sides.
[0015] Furthermore, the fit clearance between the spherical curved surface of the spherical self-aligning bearing bush and the spherical mounting groove of the bearing support is 0 to 0.05 mm.
[0016] Furthermore, the spherical self-aligning bearing adopts a double-layer composite structure with a carbon steel substrate and a Babbitt alloy coating.
[0017] Furthermore, two top shaft oil bladders are symmetrically opened on the inner wall of the lower half of the spherical self-aligning bearing.
[0018] Furthermore, the circulating lubrication and cooling assembly includes two oil sacs and two lubrication and cooling oil inlet channels;
[0019] Two oil bladders and two lubrication and cooling oil inlet channels are all set on the spherical self-aligning bearing. The two oil bladders are symmetrically arranged in the middle of the inner wall of the spherical self-aligning bearing. The top of the lubrication and cooling oil inlet channel is connected to the corresponding oil bladder. After the bottom of the two lubrication and cooling oil inlet channels merge and connect, they extend to the bottom of the spherical self-aligning bearing and are connected to the external oil passage.
[0020] Furthermore, the jacking oil circulation assembly includes two nozzles and two jacking oil inlet channels;
[0021] The two nozzles are symmetrically arranged at the lowest position of the inner wall of the spherical self-aligning bearing. One end of the top shaft oil inlet channel is connected to the lower side of the nozzle, and the other end passes through the front or rear side wall of the spherical self-aligning bearing and is connected to the external top shaft oil circuit.
[0022] Furthermore, the limiting and positioning component includes two corner pads, an anti-rotation positioning pin, and an adjusting shim;
[0023] Two corner shims are symmetrically arranged at the bottom of the left and right sides of the bearing support. A vertical anti-rotation positioning pin is inserted through the middle of each corner shim. The top of the anti-rotation positioning pin is inserted into the bearing support, and the bottom of the anti-rotation positioning pin is inserted into the bearing housing. Adjusting shims are respectively provided between the top of the corner shim and the bearing support, between the side of the corner shim and the bearing support, and between the bottom middle of the bearing support and the bearing housing.
[0024] Furthermore, the limiting and positioning component also includes a travel limiting block;
[0025] The lower end of the travel limit block is embedded in the top of the spherical self-aligning bearing, and the upper end is embedded in the bearing support, which is used to limit the self-aligning swing stroke of the spherical self-aligning bearing.
[0026] Beneficial effects:
[0027] This solution can automatically swing and align itself when the rotor deflection changes or thermal expansion causes shaft misalignment, maintaining concentricity between the journal and the bearing and a uniform oil film. It also features a reasonable limit anti-rotation structure and an optimized multi-oil wedge oil inlet structure, reducing bearing temperature and improving operational stability.
[0028] The spherical self-aligning pair automatically compensates for shaft misalignment caused by rotor deflection and thermal expansion, avoiding uneven loading and localized dry friction. The optimized multi-oil wedge inlet groove forms a stable hydrodynamic oil film at high linear velocities in subcritical retrofitted units, reducing bearing temperature by 10–20°C; the line contact limit block reduces frictional losses during self-aligning oscillation and prevents the concave spherical seat from rotating; the split-type bushing structure facilitates on-site replacement, and the thermal expansion clearance design adapts to start-up, shutdown, and variable load conditions.
[0029] This bearing is suitable for low-pressure rotor support scenarios in 310MW subcritical steam turbines. The split bearing support facilitates on-site disassembly and replacement of the unit. The spherical pair adopts IT5 grade machining accuracy and Ra≤0.8μm scraped spherical surface to match the large temperature difference deformation of the unit. The multiple limiting structure works together to constrain the rotation and excessive swing of the bearing bush. During operation, the shaft vibration index is stably controlled within the standard qualified range of the unit, completely avoiding the failure of unilateral load and local dry friction bearing bush. Attached Figure Description
[0030] Figure 1 This is a mid-section schematic diagram of the main view of a spherical self-aligning sliding bearing for a subcritical retrofit unit according to the present invention;
[0031] Figure 2 This is a partial cross-sectional schematic diagram of the top view of a spherical self-aligning sliding bearing for a subcritical retrofit unit according to the present invention;
[0032] Figure 3 This is a mid-section schematic diagram of the side view of a spherical self-aligning sliding bearing for a subcritical retrofit unit according to the present invention;
[0033] The component names corresponding to the labels in the figures are as follows:
[0034] 1—Bearing support, 2—Spherical self-aligning bearing shell, 3—Angle pad, 4—Anti-rotation positioning pin, 6—Adjusting shim, 7—Stroke limit block, 8—Nozzle, 9—Lubrication and cooling oil inlet channel, 10—Oil return channel, 11—Top shaft oil inlet channel, 12—Lubricating oil bladder, 13—Top shaft oil bladder. Detailed Implementation
[0035] Specific Implementation Method 1: A spherical self-aligning sliding bearing for a subcritical retrofit unit, comprising a bearing support 1, a spherical self-aligning bearing bush 2, a limiting and positioning assembly, a circulating lubrication and cooling assembly, and a top shaft oil circulation assembly;
[0036] The bearing support 1 is used to be installed on the bearing housing. A spherical mounting groove is opened on the inner side wall of the bearing support 1. The outer side wall of the spherical self-aligning bearing bush 2 is a spherical curved surface. The spherical self-aligning bearing bush 2 is installed in the spherical mounting groove with clearance fit, and can achieve ±3° adaptive swing self-alignment relative to the bearing support 1.
[0037] Two symmetrical oil grooves are evenly opened on the inner wall of the spherical self-aligning bearing 2, and an oil return channel 10 is provided on the oil groove;
[0038] A limit positioning component is assembled between the bearing support 1 and the spherical self-aligning bearing bush 2 for circumferential limit and position positioning of the spherical self-aligning bearing bush 2.
[0039] The circulating lubrication and cooling assembly and the top shaft oil circulation assembly are located in the lower half of the spherical self-aligning bearing 2. The circulating lubrication and cooling assembly is used to achieve uniform lubrication and cooling of the entire inner wall of the spherical self-aligning bearing 2, and the top shaft oil circulation assembly is used to lift the rotor to a preset height during the unit start-up phase.
[0040] This design is specifically for the modification of the low-pressure rotor support of a 310MW subcritical single reheat, three-cylinder double exhaust, direct air-cooled extraction condensing steam turbine generator set.
[0041] In this embodiment: the whole includes a bearing support 1, a spherical self-aligning bearing bush 2, a limiting and positioning assembly, a circulating lubrication and cooling assembly, and a top shaft oil circulation assembly;
[0042] The bearing support 1 is used for integral installation inside the turbine bearing housing. The inner ring of the bearing support 1 is integrally machined into a spherical mounting groove. The outer circle of the spherical self-aligning bearing bush 2 is a high-precision machined spherical curved surface. The spherical self-aligning bearing bush 2 is assembled in the spherical mounting groove with an overall clearance. The spherical mating clearance between the two is controlled within 0 to 0.05 mm. The spherical pair can achieve adaptive swing self-alignment within a range of ±3° to compensate for the journal misalignment caused by rotor deflection and cylinder thermal expansion after the unit modification.
[0043] A complete set of limiting and positioning components is assembled between the bearing support and the spherical self-aligning bearing bush to simultaneously achieve triple constraints of circumferential anti-rotation, axial positioning, and maximum swing angle limitation of the spherical self-aligning bearing bush, preventing the spherical self-aligning bearing bush from rotating or swinging excessively with the rotor.
[0044] The circulating lubrication and cooling components and the top shaft oil circulation components are all integrated and arranged in the lower half of the bearing area of the spherical self-aligning bearing. The circulating lubrication and cooling components continuously supply oil to the middle of the inner wall of the bearing, forming a full-area dynamic pressure oil film and carrying away frictional heat to achieve uniform lubrication and cooling. The top shaft oil circulation components supply high-pressure oil during the low-speed stages of unit startup and shutdown, lifting the rotor journal as a whole to avoid direct scraping and wear of the Babbitt alloy layer under low-speed conditions.
[0045] Specific Implementation Method 2: A spherical self-aligning sliding bearing for a subcritical retrofit unit, wherein the bearing support 1 is a split 25# steel forged component.
[0046] In this embodiment: the spherical surface inside the spherical mounting groove on the inner side of the bearing support is precision scraped and ground, with a surface roughness Ra≤0.8μm and a spherical surface dimensional accuracy of IT5 grade, ensuring uniform fit of the spherical self-aligning pair and avoiding local point contact that aggravates wear.
[0047] Other implementation methods are the same as those in Specific Implementation Method 1.
[0048] Specific implementation method 3: A spherical self-aligning sliding bearing for subcritical retrofit units, wherein the upper half of the bearing support 1 is provided with mounting flanges with mounting holes on both the left and right sides, and the lower half of the bearing support 1 is provided with positioning stops on both the left and right sides.
[0049] In this embodiment: the mounting flange is used to connect to the bearing housing.
[0050] Other implementation methods are the same as those in Specific Implementation Method 1.
[0051] Specific Implementation Method 4: A spherical self-aligning sliding bearing for a subcritical retrofit unit, wherein the fit clearance between the spherical curved surface of the spherical self-aligning bearing bush 2 and the spherical mounting groove of the bearing support 1 is 0 to 0.05 mm.
[0052] In this embodiment: a gap less than 0mm will cause the spherical surface to jam and lose its self-aligning function, while a gap greater than 0.05mm will cause the bearing to wobble and the unit to vibrate excessively. This gap range is perfectly suited to the large temperature difference and variable load operation conditions of subcritical units.
[0053] Other implementation methods are the same as those in Specific Implementation Method 1.
[0054] Specific Implementation Method 5: A spherical self-aligning sliding bearing for subcritical retrofit units, wherein the spherical self-aligning bearing bush 2 adopts a double-layer composite structure with a carbon steel substrate and a Babbitt alloy coating.
[0055] In this embodiment: the inner working surface of the bearing bush is centrifugally cast with a 3.5mm thick tin-based Babbitt alloy ZSnSb12Cu6ZnAg. The Babbitt alloy layer and the carbon steel substrate are metallurgically bonded through high-temperature fusion, preventing the alloy layer from peeling off under long-term high and low temperature cyclic conditions of the unit; the inner hole of the Babbitt alloy is precision bored to ensure the roundness of the journal fit.
[0056] The spherical self-aligning bearing 2 has a base of 45# carbon steel forging. The inner working surface of the bearing is centrifugally cast with a 3.5mm thick tin-based Babbitt alloy ZSnSb12Cu6ZnAg. The Babbitt alloy and the carbon steel base are fused together at high temperature to resist the alternating stress of the unit's 80-120℃ hot and cold cycles and prevent the alloy layer from cracking, peeling and falling off.
[0057] Other implementation methods are the same as those in Specific Implementation Method 1.
[0058] Specific Implementation Method Six: A spherical self-aligning sliding bearing for a subcritical retrofit unit, wherein two top shaft oil sacs 13 are symmetrically opened on the inner wall of the lower half of the spherical self-aligning bearing bush 2.
[0059] In this embodiment: when the unit starts up, high-pressure jacking oil is filled into the jacking oil bladder, forming a high-pressure oil pad between the journal and the bearing, which lifts the rotor as a whole and eliminates dry friction between the journal and the Babbitt alloy.
[0060] The single-headed shaft oil bladder has an encirclement angle A=30°. After high-pressure oil is filled in, it can form a complete annular high-pressure oil pad, which stably lifts the rotor journal by 0.12~0.20mm, completely isolating the journal from the Babbitt alloy layer and preventing low-speed friction damage during unit start-up and shutdown.
[0061] Other implementation methods are the same as those in Specific Implementation Method 1.
[0062] Specific Implementation Method Seven: A spherical self-aligning sliding bearing for a subcritical retrofit unit, wherein the circulating lubrication and cooling assembly includes two oil bladders 12 and two lubrication and cooling oil inlet channels 9;
[0063] Two oil bladders 12 and two lubrication and cooling oil inlet channels 9 are all provided on the spherical self-aligning bearing 2. The two oil bladders 12 are symmetrically arranged in the middle of the inner wall of the spherical self-aligning bearing 2. The top of the lubrication and cooling oil inlet channel 9 is connected to the corresponding oil bladder 12. After the bottom of the two lubrication and cooling oil inlet channels 9 converges and connects, they extend to the bottom of the spherical self-aligning bearing 2 and are connected to the external oil passage.
[0064] In this embodiment: the two lubrication and cooling oil inlet channels flow downwards and merge into a total oil inlet channel, which passes through the bottom of the spherical self-aligning bearing and connects to the external lubrication oil station pipeline; after the lubricating oil flows in from the bottom, it flows upwards and splits into the oil sacs on both sides, spreading evenly along the circumference of the bearing to form a continuous dynamic pressure oil film, while continuously carrying away the frictional temperature rise of the bearing, which can stably reduce the bearing temperature by 10-20°C.
[0065] Other implementation methods are the same as those in Specific Implementation Method 1.
[0066] Specific implementation method 8: A spherical self-aligning sliding bearing for a subcritical retrofit unit, wherein the jacking oil circulation assembly includes two nozzles 8 and two jacking oil inlet channels 11;
[0067] The two nozzles 8 are symmetrically arranged at the lowest position of the inner wall of the spherical self-aligning bearing 2. One end of the top shaft oil inlet channel 11 is connected to the lower side of the nozzle 8, and the other end passes through the front or rear side wall of the spherical self-aligning bearing 2 and is connected to the external top shaft oil passage.
[0068] In this embodiment: during the unit startup phase, high-pressure oil is injected into the jacking oil bladder through the jacking oil inlet channel and nozzle to establish a high-pressure support oil pad; after the unit reaches the rated speed, the jacking oil pump stops operating, and the rotor load is independently borne by the dynamic pressure oil film.
[0069] Other implementation methods are the same as those in Specific Implementation Method 1.
[0070] Specific Implementation Method Nine: A spherical self-aligning sliding bearing for a subcritical retrofit unit, wherein the limiting and positioning assembly includes two corner pads 3, an anti-rotation positioning pin 4, and an adjusting shim 6;
[0071] Two corner pads 3 are symmetrically arranged at the bottom of the left and right sides of the bearing support 1. A vertical anti-rotation positioning pin 4 is inserted through the middle of each corner pad 3. The top of the anti-rotation positioning pin 4 is inserted into the bearing support 1, and the bottom of the anti-rotation positioning pin 4 is inserted into the bearing housing. Adjusting shims 6 are respectively provided between the top of the corner pad 3 and the bearing support 1, between the side of the corner pad 3 and the bearing support 1, and between the bottom middle of the bearing support 1 and the bearing housing.
[0072] In this embodiment: two sets of corner pads are bolted to the left and right sides of the bottom of the bearing support, respectively. A vertical through hole is opened in the middle of each corner pad, and the anti-rotation positioning pin passes through the through hole. The upper end of the anti-rotation positioning pin is inserted into the pin hole of the bearing support, and the lower end is inserted into the positioning hole of the bearing housing, which completely restricts the circumferential rotation of the spherical self-aligning bearing and avoids the bearing bearing from self-rotating and wearing during the self-aligning process. Adjusting shims are laid at three points: the top surface of the corner pad and the bottom surface of the bearing support, the side surface of the corner pad and the side wall of the bearing support, and the middle of the bottom end of the bearing support and the bearing housing support surface. By adding or removing shims of different thicknesses, the overall elevation and left and right level of the bearing can be accurately corrected on site to meet the alignment requirements of the shaft system after the unit is modified.
[0073] Alternatively, the adjusting shims can be an adjusting plate or a set of thin shims.
[0074] Other implementation methods are the same as those in Specific Implementation Method 1.
[0075] Specific Implementation Method 10: A spherical self-aligning sliding bearing for a subcritical retrofit unit, wherein the limiting and positioning component further includes a stroke limiting block 7;
[0076] The lower end of the travel limit block 7 is embedded in the top of the spherical self-aligning bearing 2, and the upper end is embedded in the bearing support 1, which is used to limit the self-aligning swing stroke of the spherical self-aligning bearing 2.
[0077] In this embodiment: the limiting and positioning component is equipped with a stroke limiting block. The lower end of the stroke limiting block is embedded in the reserved groove on the top of the spherical self-aligning bearing, and the upper end is inserted into the limiting groove on the top of the spherical mounting groove of the bearing support. The stroke limiting block and the groove are reserved with swing gaps on the left and right sides, and the gaps correspond to the maximum swing angle of the spherical surface ±3°. When the bearing swings to the limit angle, the stroke limiting block 7 is in contact with the side wall of the support groove to limit the swing, preventing the spherical self-aligning bearing from swinging excessively and the spherical surface from being overloaded and worn on one side.
[0078] Other implementation methods are the same as those in Specific Implementation Method 1.
[0079] Working principle:
[0080] The bearing support 1 has a spherical mounting groove machined inside, and the outer side of the spherical self-aligning bearing bush 2 is a matching spherical curved surface. The clearance between the two is controlled within 0 to 0.05 mm, allowing for free swing of ±3°. After the subcritical unit is modified, the rotor weight and span increase, and static deflection and thermal expansion offset occur during start-up, shutdown, and load changes, causing misalignment between the journal and the theoretical center of the bearing. The spherical self-aligning bearing bush 2 can automatically swing slightly according to the direction of the journal force, always ensuring uniform contact between the journal and the inner surface of the bearing bush's Babbitt alloy, avoiding local high pressure on one side, oil film rupture, and bearing failure. The top stroke limit block 7 is locked between the bearing support 1 and the spherical self-aligning bearing bush 2, limiting the maximum swing angle of the bearing bush to no more than ±3°, preventing excessive offset of the spherical pair and unilateral spherical wear. The two side corner pads 3 and anti-rotation positioning pins 4 lock the bearing support and bearing housing, preventing the spherical self-aligning bearing bush 2 from rotating with the rotor circumferentially and eliminating uneven wear. The corner shim 3, adjusting plate 5, and adjusting shim 6 are used together. The thickness of the shims can be increased or decreased on site to calibrate the bearing elevation and levelness, and to re-align the shaft system after the modification.
Claims
1. A spherical self-aligning sliding bearing for subcritical retrofit units, characterized in that: Includes bearing support (1), spherical self-aligning bearing shell (2), limit positioning assembly, circulating lubrication and cooling assembly and top shaft oil circulation assembly; The bearing support (1) is used to be installed on the bearing housing. The inner side wall of the bearing support (1) is provided with a spherical mounting groove. The outer side wall of the spherical self-aligning bearing (2) is a spherical curved surface. The spherical self-aligning bearing (2) is installed in the spherical mounting groove with clearance fit, and can achieve ±3° adaptive swing self-alignment relative to the bearing support (1). Two symmetrical oil grooves are evenly opened on the inner wall of the spherical self-aligning bearing (2), and the oil grooves are provided with oil return channels (10). A limit positioning component is assembled between the bearing support (1) and the spherical self-aligning bearing bush (2) for circumferential limit and position positioning of the spherical self-aligning bearing bush (2); The circulating lubrication and cooling assembly and the top shaft oil circulation assembly are located in the lower half of the spherical self-aligning bearing (2). The circulating lubrication and cooling assembly is used to achieve uniform lubrication and cooling of the entire inner wall of the spherical self-aligning bearing (2). The top shaft oil circulation assembly is used to lift the rotor to a preset height during the unit start-up phase.
2. The spherical self-aligning sliding bearing for subcritical retrofit units according to claim 1, characterized in that: The bearing support (1) is a split 25# steel forged steel component.
3. The spherical self-aligning sliding bearing for subcritical retrofit units according to claim 1, characterized in that: The upper part of the bearing support (1) is provided with mounting flanges with mounting holes on the left and right sides, and the lower part of the bearing support (1) is provided with positioning stops on the left and right sides.
4. A spherical self-aligning sliding bearing for a subcritical retrofit unit according to claim 1, characterized in that, The fit clearance between the spherical curved surface of the spherical self-aligning bearing bush (2) and the spherical mounting groove of the bearing support (1) is 0 to 0.05 mm.
5. A spherical self-aligning sliding bearing for a subcritical retrofit unit according to claim 1, characterized in that: The spherical self-aligning bearing (2) adopts a double-layer composite structure with carbon steel substrate and Babbitt alloy coating.
6. A spherical self-aligning sliding bearing for subcritical retrofitted units according to claim 1, characterized in that, The lower half of the spherical self-aligning bearing (2) has two symmetrically arranged top shaft oil sacs (13) on the inner wall.
7. A spherical self-aligning sliding bearing for subcritical retrofit units according to claim 1, characterized in that, The circulating lubrication and cooling assembly includes two oil bladders (12) and two lubrication and cooling oil inlet channels (9); Two oil bladders (12) and two lubrication and cooling oil inlet channels (9) are all set on the spherical self-aligning bearing (2). The two oil bladders (12) are symmetrically arranged in the middle of the inner wall of the spherical self-aligning bearing (2). The top of the lubrication and cooling oil inlet channel (9) is connected to the corresponding oil bladder (12). After the bottom of the two lubrication and cooling oil inlet channels (9) converge and connect, they extend to the bottom of the spherical self-aligning bearing (2) and are connected to the external oil passage.
8. A spherical self-aligning sliding bearing for subcritical retrofitted units according to claim 1, characterized in that, The jacking oil circulation assembly includes two nozzles (8) and two jacking oil inlet channels (11). The two nozzles (8) are symmetrically arranged at the lowest position of the inner wall of the spherical self-aligning bearing (2). One end of the top shaft oil inlet channel (11) is connected to the lower side of the nozzle (8), and the other end passes through the front or rear side wall of the spherical self-aligning bearing (2) and is connected to the external top shaft oil circuit.
9. A spherical self-aligning sliding bearing for a subcritical retrofit unit according to claim 1, characterized in that, The limiting and positioning component includes two corner pads (3), an anti-rotation positioning pin (4), and an adjusting shim (6). Two corner pads (3) are symmetrically arranged at the bottom of the left and right sides of the bearing support (1). A vertical anti-rotation positioning pin (4) is inserted through the middle of each corner pad (3). The top of the anti-rotation positioning pin (4) is inserted into the bearing support (1), and the bottom of the anti-rotation positioning pin (4) is inserted into the bearing box. Adjusting shims (6) are respectively provided between the top of the corner pad (3) and the bearing support (1), between the side of the corner pad (3) and the bearing support (1), and between the bottom middle of the bearing support (1) and the bearing box.
10. A spherical self-aligning sliding bearing for a subcritical retrofit unit according to claim 1, characterized in that, The limiting and positioning component also includes a travel limiting block (7); The lower end of the travel limit block (7) is embedded in the top of the spherical self-aligning bearing (2), and the upper end is embedded in the bearing support (1) to limit the self-aligning swing stroke of the spherical self-aligning bearing (2).