A wind power main shaft sliding bearing with a PAI composite coating and a replaceable textured journal sleeve and a preparation and repair method thereof

Abstract

The application discloses a wind power main shaft sliding bearing with a PAI composite coating and a replaceable textured journal sleeve and a manufacturing and repairing method thereof, and relates to the technical field of main transmission bearing of wind turbine generator set. The wind power main shaft sliding bearing comprises a main shaft, a replaceable functional journal sleeve fixedly connected with the main shaft in a same rotating mode, and a bearing bush assembly arranged in cooperation with the replaceable functional journal sleeve. A continuous interconnected non-through micro anchoring structure is formed on the surface of the bearing bush base body. A PAI-based composite coating is selectively arranged on the micro anchoring structure and covers the working arc segment. The outer surface of the replaceable functional journal sleeve is provided with a first functional micro unit for storing lubricating medium and a second functional micro unit filled with solid lubricating material. Through the out-of-plane cooperative design of the "soft contact compliant layer-hard functional surface layer", the lubricating stability, the anti-scratching capability, the wear resistance and the maintainability of the sliding bearing under the conditions of low-speed heavy load, amplitude alternating load and frequent start-stop of the wind turbine generator set are improved.

Description

Technical Field

[0001] This invention relates to the field of wind turbine main drive support technology, and in particular to a wind turbine main shaft sliding bearing with PAI composite coating and replaceable textured journal sleeve, and its preparation and repair methods. Background Technology

[0002] As wind turbines develop towards larger capacity and larger size, the main drive system is subjected to complex operating conditions such as low-speed heavy loads, variable amplitude alternating loads, impact vibrations, and frequent start-stop cycles. Compared with rolling bearings, sliding bearings have advantages such as surface contact bearing, uniform load distribution, smooth operation, relatively simple structure, and easy modular maintenance, making them highly promising for application in large wind turbines.

[0003] However, wind turbine sliding bearings still face multiple challenges in engineering applications. Under low-speed, heavy-load, and frequent start-stop conditions, the lubrication interface is prone to mixed lubrication, boundary lubrication, or even localized dry friction, resulting in insufficient oil film stability and consequently, direct surface contact, scratches, and accelerated wear. Traditional metal friction pairs are prone to adhesive wear, abrasive wear, and localized failure under such conditions, and relying solely on the metal bearing layer is usually insufficient to simultaneously achieve compliance, friction reduction and wear resistance, and lubrication compensation during start-stop phases.

[0004] Polyamide-imide (PAI) materials possess good heat resistance, mechanical properties, and tribological properties, making them beneficial for improving interfacial compliance, scratch resistance, and environmental tolerance when used as coatings for sliding bearings. However, under heavy loads, thermal cycling, and alternating load conditions, the adhesion reliability between PAI-type coatings and the metal substrate remains a crucial factor affecting long-term service performance. If coated directly onto a flat substrate surface, the effective bonding area at the interface is limited, and the interfacial shear resistance is insufficient, making it prone to localized delamination, warping, or crack propagation at edges, areas of geometric abrupt changes, or under cyclic loading.

[0005] On the other hand, surface microtexturing technology can improve the performance of sliding pairs by storing oil, guiding flow, accommodating wear debris, and improving local lubrication. However, if microtextures bearing the main frictional functions are directly formed on the surface of a polymer coating, under low-speed, heavy-load, frequent start-stop, and alternating load conditions in wind turbine bearings, these microtextures may be more prone to local deformation, edge blunting, or contour attenuation, thus affecting their long-term stable oil storage and lubrication regulation functions. If microfunctional structures are directly set on the surface of the spindle body, although the shape retention can be improved, the spindle is a large, high-value core component. Once the surface functional structure wears and fails, the cost of on-site repair and replacement is high, and the maintenance flexibility is insufficient.

[0006] Therefore, it is necessary to provide a new wind turbine sliding bearing structure that enables the bearing bush to have compliant contact and anti-scrubbing capabilities, and the shaft side to have stable oil storage and start-stop lubrication functions, while taking into account adhesion reliability, manufacturing feasibility and ease of later repair, so as to meet the engineering application requirements of wind turbine units under low-speed heavy load, alternating load and frequent start-stop conditions. Summary of the Invention

[0007] The purpose of this invention is to provide a wind turbine main shaft sliding bearing with a PAI composite coating and a replaceable textured journal sleeve, as well as its manufacturing and repair methods. By setting a continuous interconnected non-through micro-anchoring structure between the bearing substrate and the PAI-based composite coating, and setting a replaceable functional journal sleeve on the outer periphery of the main shaft, and forming dual-functional micro-units for oil storage and replenishment and start-stop auxiliary lubrication on the outer surface of the functional journal sleeve, a non-planar synergistic friction pair of "soft contact compliant layer - hard functional surface layer" is constructed, thereby improving the lubrication stability, anti-scratch, wear resistance and maintainability of the wind turbine sliding bearing under low-speed heavy load, variable amplitude alternating load and frequent start-stop conditions.

[0008] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: The present invention discloses a wind turbine main shaft sliding bearing with PAI composite coating and replaceable textured journal sleeve, characterized in that: it includes a main shaft, a bearing assembly and a replaceable functional journal sleeve, wherein the replaceable functional journal sleeve is disposed on the outer periphery of the main shaft and is fixedly connected to the main shaft to rotate together, and the bearing assembly is disposed on the outside of the replaceable functional journal sleeve. in, The bearing assembly includes a bearing substrate, which forms a continuous interconnected non-through micro-anchoring structure facing the bearing working surface of the replaceable functional journal sleeve, and the continuous interconnected non-through micro-anchoring structure is covered with a PAI-based composite coating. The outer surface of the replaceable functional journal sleeve is provided with a plurality of first functional micro-units and second functional micro-units that are spaced apart from each other. The first functional micro-unit is an unfilled closed oil storage micro-pit, and the second functional micro-unit is a closed lubrication micro-cavity filled with solid lubricating material. The PAI-based composite coating and the outer surface of the replaceable functional journal sleeve form a non-surface cooperative friction pair.

[0009] Preferably, the PAI-based composite coating is applied only to the working arc segment of the bearing assembly, and forms an edge recess area and / or a thickness gradient transition area in the edge region.

[0010] Preferably, the replaceable functional journal sleeve is connected to the main shaft through one of the following: interference fit, heat fitting, cold fitting, or tapered pressing fit, and is fixed by an axial limiting structure and a circumferential anti-rotation structure.

[0011] Preferably, the continuous interconnected non-through micro-anchoring structure is a mesh, honeycomb, or curved interconnected structure.

[0012] Preferably, the PAI-based composite coating is a polyamide-imide resin-based composite coating containing one or more fillers selected from polytetrafluoroethylene, graphite, molybdenum disulfide, hexagonal boron nitride, zirconium oxide, carbon fiber, and ceramic particles.

[0013] Preferably, the first functional micro-unit has an equivalent size of 50-1000 μm and a depth of 5-150 μm; the second functional micro-unit has an equivalent size of 30-500 μm and a depth of 5-80 μm.

[0014] Preferably, the first functional micro-unit and the second functional micro-unit are distributed in a periodically uniform mixed manner along the outer surface of the replaceable functional journal sleeve, and functional bands, low-density areas or edge restricted areas are provided along the axial direction.

[0015] Preferably, the replaceable functional journal sleeve is an integral sleeve structure or a split sleeve structure; the bearing assembly is a split structure, including an upper bearing and a lower bearing, the upper bearing and the lower bearing together forming a sliding support hole that mates with the replaceable functional journal sleeve.

[0016] A method for manufacturing a wind turbine main shaft sliding bearing with a PAI composite coating and a replaceable textured journal sleeve as described above includes the following steps: S1, a continuous interconnected non-penetrating micro-anchoring structure is formed on the surface of the bearing substrate; S2, the bearing substrate with the continuous interconnected non-through micro-anchoring structure is degreased, roughened, cleaned and subjected to necessary interface treatment; S3, selectively prepare a PAI-based composite coating on the working arc segment of the continuous interconnected non-through micro-anchoring structure, and retain the edge relief area; S4, the PAI-based composite coating is subjected to staged curing and finishing treatment; S5, a first functional micro-unit and a second functional micro-unit are prepared on the outer surface of the replaceable functional journal sleeve, and solid lubricating material is filled into the second functional micro-unit; S6: Fix the replaceable functional journal sleeve to the outer periphery of the main shaft; S7: Assemble the main shaft with the replaceable functional journal sleeve and the bearing assembly to form a sliding bearing.

[0017] A repair method for a wind turbine main shaft sliding bearing with a PAI composite coating and a replaceable textured journal sleeve as described above includes the following steps: R1 is used to detect and evaluate the wear condition of replaceable functional journal sleeves and bearing assemblies. R2, when the first functional micro-unit and / or the second functional micro-unit of the replaceable functional journal sleeve wears out and fails, the replaceable functional journal sleeve is disassembled and replaced or reprocessed for repair. R3, when the PAI-based composite coating is worn, partially delaminated or its performance degraded, the bearing assembly is recoated for repair or replaced entirely; R4, reassemble the repaired replaceable functional journal sleeve and bearing assembly; R5, after assembly, performs gap verification and operational validation.

[0018] Compared with the prior art, the beneficial technical effects of the present invention are as follows: 1) This invention forms a heterogeneous synergistic structure of “soft contact compliant layer - hard functional surface layer” by setting a PAI-based composite coating on the bearing bush side and a replaceable functional journal sleeve and its dual-functional micro unit on the shaft side, which better balances running-in adaptability, anti-scratch ability and long-term surface functional stability.

[0019] 2) The present invention does not place the micro-textures that bear the main friction function directly on the surface of the polymer coating, but on the surface of the metal functional journal sleeve, which can improve the micro-unit morphology retention capability and long-term service stability.

[0020] 3) The present invention sets up a continuous interconnected non-through micro-anchoring structure between the bearing substrate and the PAI-based composite coating, which can form a continuous mechanical interlocking path, increase the effective bonding area of ​​the interface, enhance the lateral locking effect of the interface and improve the interface shear resistance, thereby reducing the risk of coating delamination under heavy load alternating working conditions.

[0021] 4) By setting up two types of functional micro-units, namely unfilled oil storage micro-pits and lubrication micro-cavities filled with solid lubricating material, the present invention enables different micro-units to undertake the functions of lubricating medium storage and replenishment and start-stop auxiliary lubrication, thereby improving the interface lubrication state of wind turbine bearings during start-stop and boundary lubrication stages.

[0022] 5) This invention introduces a replaceable functional journal sleeve, which decouples the micro-functional surface from the main shaft body. It can be independently replaced or remanufactured and repaired after the functional unit wears out, which greatly improves the maintenance convenience and engineering feasibility of sliding bearings of large wind turbine units. Attached Figure Description

[0023] The present invention will be further described below with reference to the accompanying drawings.

[0024] Figure 1 This is a schematic diagram of the overall structure of the wind turbine main shaft sliding bearing with PAI composite coating and replaceable textured journal sleeve of the present invention. Figure 2 This is a magnified cross-sectional view of a portion of the friction pair of the present invention; Figure 3 This is a schematic diagram showing the fixed connection between the replaceable functional journal sleeve and the main shaft of the present invention; Figure 4 This is a schematic diagram of the continuous interconnected non-through micro-anchoring structure on the surface of the bearing substrate of the present invention. Figure 1 ; Figure 5 This is a schematic diagram of the continuous interconnected non-through micro-anchoring structure on the surface of the bearing substrate of the present invention. Figure 2 ; Figure 6 This is a schematic diagram showing the distribution of the first and second functional micro-units on the outer surface of the replaceable functional journal sleeve of the present invention. Figure 1 ; Figure 7 Schematic diagram of the functional micro-unit structure on the outer surface of the replaceable functional journal sleeve Figure 2 ; Figure 8 This is a flowchart of the manufacturing method of the present invention; Figure 9 This is a flowchart of the repair method of the present invention.

[0025] Explanation of reference numerals in the attached drawings: 1—main shaft; 2—bearing bush; 21—continuous interconnected non-through micro-anchoring structure; 22—PAI-based composite coating; 3—replaceable functional journal sleeve; 31—first functional micro-unit; 32—second functional micro-unit; 33—axial limiting structure; 4—bearing sleeve. Detailed Implementation

[0026] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0027] like Figure 1-7 As shown, a wind turbine main shaft sliding bearing with PAI composite coating and replaceable textured journal sleeve includes a main shaft 1, a bearing assembly 2 and a replaceable functional journal sleeve 3. The replaceable functional journal sleeve 3 is disposed on the outer periphery of the main shaft 1 and is fixedly connected to the main shaft 1 to rotate together. The bearing assembly 2 is disposed on the outside of the replaceable functional journal sleeve 3. in, The bearing assembly 2 includes a bearing substrate, and the bearing substrate forms a continuous interconnected non-through micro-anchoring structure 21 facing the bearing working surface of the replaceable functional journal sleeve 3. The continuous interconnected non-through micro-anchoring structure 21 is covered with a PAI-based composite coating 22. The outer surface of the replaceable functional journal sleeve 3 is provided with a plurality of first functional micro-units 31 and second functional micro-units 32 spaced apart from each other. The first functional micro-unit 31 is an unfilled closed oil storage micro-pit, used to store lubricating medium and realize local fluid replenishment during relative sliding. The second functional micro-unit 32 is a closed lubrication micro-cavity filled with solid lubricating material, used to improve the friction state during the start-up and shutdown stage or the boundary lubrication stage. In specific implementation, the solid lubricating material in the second functional micro-unit 32 can be a single solid lubricating material or a composite solid lubricating material to adapt to different temperatures, loads and start-up and shutdown conditions. The PAI-based composite coating 22 and the outer surface of the replaceable functional journal sleeve 3 form a non-surface cooperative friction pair.

[0028] This invention forms a heterogeneous synergistic structure of "soft contact compliant layer - hard functional surface layer" by setting a PAI-based composite coating on the bearing bush side and a replaceable functional journal sleeve and its dual-functional micro-unit on the shaft side. This arrangement effectively balances running-in adaptability, scratch resistance, and long-term surface functional stability. Simultaneously, the replaceable functional journal sleeve design decouples the micro-functional surface from the main shaft body, allowing for independent replacement or remanufacturing repair after functional unit wear and failure. This improves the maintenance convenience and engineering feasibility of sliding bearings in large wind turbine units.

[0029] like Figure 2 As shown, the PAI-based composite coating 22 is only applied to the working arc segment of the bearing assembly 2, and forms an edge recess area and / or a thickness gradient transition area in the edge region. Specifically, the PAI-based composite coating 22 is preferably applied to the main working arc segment of the bearing, while forming an edge recess area and / or a thickness gradient transition area at the bearing end, near the split opening, and at the edge of the oil supply hole or oil groove.

[0030] Specifically, the replaceable functional journal sleeve 3 is connected to the main shaft 1 through one of the following methods: interference fit, heat fitting, cold fitting, or tapered surface clamping fit, and is fixed by an axial limiting structure 33 and a circumferential anti-rotation structure, such as... Figure 3 As shown. Specifically, axial positioning can be achieved through structures such as shaft shoulders, retaining rings, lock nuts, and end caps, while circumferential anti-rotation can be achieved through structures such as flat keys, splines, anti-rotation pins, or circumferential stops.

[0031] Specifically, such as Figure 4 , 5As shown, the continuous interconnected non-through micro-anchoring structure 21 is a mesh, honeycomb, or curved interconnected structure. The micro-anchoring structure 21 is preferably a shallow, rounded, non-through mesh or curved interconnected structure, and its main function is to improve the mechanical interlocking strength, effective bonding area, and interface shear resistance between the PAI-based composite coating 22 and the bearing substrate 2, thereby helping to reduce the risk of coating delamination under heavy-load alternating working conditions.

[0032] Specifically, the PAI-based composite coating 22 is a polyamide-imide resin-based composite coating containing one or more fillers selected from polytetrafluoroethylene, graphite, molybdenum disulfide, hexagonal boron nitride, zirconium oxide, carbon fiber, and ceramic particles.

[0033] Specifically, such as Figure 6 , 7 As shown, the first functional micro-unit 31 has an equivalent size of 50–1000 μm and a depth of 5–150 μm; the second functional micro-unit 32 has an equivalent size of 30–500 μm and a depth of 5–80 μm. In a preferred embodiment, the continuous interconnected non-through micro-anchoring structure 21 has a structural depth of 5–80 μm and an equivalent feature size of 50–500 μm. The thickness of the PAI-based composite coating 22 is 20–300 μm, preferably 40–150 μm. The first functional micro-unit 31 has an equivalent size of 100–600 μm, a depth of 10–80 μm, and a surface density or area ratio preferably of 3%–25%. The second functional micro-unit 32 has an equivalent size of 50–300 μm, a depth of 5–50 μm, and a surface density preferably lower than that of the first functional micro-unit 31.

[0034] Specifically, the first functional micro-unit 31 and the second functional micro-unit 32 are distributed circumferentially in a periodic and uniform mixed pattern on the outer surface of the replaceable functional journal sleeve 3, and functional bands, low-density areas, or edge-restricted areas are set along the axial direction. This invention improves the interface lubrication state of wind turbine bearings during start-up, shutdown, and boundary lubrication stages by setting two types of functional micro-units: unfilled oil-storing micro-pits and lubrication micro-cavities filled with solid lubricating material. The shapes of the first functional micro-unit 31 and the second functional micro-unit 32 are not limited to circles; they can be teardrop-shaped or hexagonal, etc.

[0035] Specifically, the replaceable functional journal sleeve 3 is an integral sleeve structure or a split sleeve structure. An integral structure helps ensure roundness and coaxiality, while a split structure facilitates quick on-site assembly and disassembly. The bearing assembly 2 is a split structure, including an upper bearing and a lower bearing, which together form a sliding support hole that mates with the replaceable functional journal sleeve 3. Figure 1As shown, the bearing bush is composed of multiple circumferentially divided units.

[0036] Specifically, the material of the replaceable functional journal sleeve 3 is preferably high-strength alloy steel, surface-strengthened steel, or other metallic materials with high hardness and good morphology retention. The hardness of the material of the replaceable functional journal sleeve 3 is higher than that of the PAI-based composite coating 22, while the elastic modulus of the PAI-based composite coating 22 is lower than that of the replaceable functional journal sleeve 3. Through the selection of materials, a mechanically complementary relationship is formed between the compliant contact layer and the morphology-stabilized functional layer. This mechanical complementarity does not emphasize universal optimality, but rather is more conducive to balancing run-in adaptability and long-term functional stability under low-speed heavy-load, frequent start-stop, and alternating operating conditions of wind turbines.

[0037] A method for manufacturing a wind turbine main shaft sliding bearing with a PAI composite coating and a replaceable textured journal sleeve as described above includes the following steps: S1, a continuous interconnected non-penetrating micro-anchoring structure is formed on the surface of the bearing substrate; specifically, the bearing substrate needs to be machined to obtain a predetermined size and geometry. The continuous interconnected non-penetrating micro-anchoring structure 21 can be obtained by laser processing, micro-milling, etching, shot peening-mask composite processing or roll forming, etc. It is preferred to form a shallow, rounded, non-penetrating grid-like or curved interconnected structure to improve the interface bonding without excessively weakening the continuity of the substrate bearing capacity.

[0038] S2, the bearing substrate with the continuous interconnected non-through micro-anchoring structure is degreased, roughened, cleaned and subjected to necessary interface treatment; if necessary, a bonding reinforcement layer may also be formed on its surface.

[0039] S3, selectively prepare a PAI-based composite coating on the working arc segment of the continuous interconnected non-through micro-anchoring structure, and retain the edge retreat area; in practice, the PAI-based composite coating 22 can be formed by spraying, scraping, dipping, brushing or other suitable processes.

[0040] S4, the PAI-based composite coating is cured and finished in stages; that is, after the coating is completed, it is cured by a staged heating method, and then it is ground, polished, honed or other finishing processes to achieve the required thickness and surface quality.

[0041] S5, a first functional micro-unit and a second functional micro-unit are prepared on the outer surface of the replaceable functional journal sleeve, and solid lubricating material is filled into the second functional micro-unit; S6: The replaceable functional journal sleeve 3 is fixed to the outer periphery of the main shaft 1. The assembly operation is mainly completed by means of interference fit, hot fit, cold fit or conical surface pressing fit, and further fixed by axial limiting structure and circumferential anti-rotation structure.

[0042] S7: Assemble the spindle with the replaceable functional journal sleeve and the bearing assembly to form a sliding bearing.

[0043] Specifically, in step S1, the continuous interconnected non-through micro-anchoring structure is obtained through laser processing, micro-milling, shot peening-mask composite processing, etching, or roll forming.

[0044] Specifically, in step S5, the micro-units can be prepared by laser processing, electrical discharge machining, micro-milling, embossing or composite processes; after the second functional micro-unit 32 is formed, it is filled with solid lubricating material and then cured, compacted or surface-trimmed so that the filling surface is lower or not higher than the adjacent metal surface.

[0045] A repair method for a wind turbine main shaft sliding bearing with a PAI composite coating and a replaceable textured journal sleeve as described above includes the following steps: R1 is used to inspect and evaluate the wear condition of the replaceable functional journal sleeve and bearing assembly. During operation, the sliding bearing after service is first disassembled and inspected, and the surface functional structure condition of the replaceable functional journal sleeve 3, the condition of the PAI-based composite coating 22 of the bearing 2, and the fit clearance are inspected and evaluated respectively.

[0046] R2, when the first functional micro-unit and / or the second functional micro-unit of the replaceable functional journal sleeve wears out, the replaceable functional journal sleeve is disassembled and replaced or reprocessed for repair; specifically, when the first functional micro-unit 31 and the second functional micro-unit 32 experience wear failure, blockage, contour decay, or significant loss of solid lubricating material, the replaceable functional journal sleeve 3 can be removed from the spindle 1 and repaired by reprocessing the micro-unit, refilling the solid lubricating material, surface finishing, or directly replacing the sleeve.

[0047] R3. When the PAI-based composite coating is worn, partially delaminated, or its performance degrades, the bearing assembly shall be recoated for repair or replaced entirely. Specifically, when the PAI-based composite coating 22 on the bearing assembly 2 is worn, partially delaminated, edge-lifted, or its performance degrades, it can be repaired by removing the failed coating, restoring or rebuilding the continuous interconnected non-through micro-anchoring structure 21, and re-preparing and curing the PAI-based composite coating 22. If necessary, the bearing assembly 2 can also be replaced directly.

[0048] R4, reassemble the repaired replaceable functional journal sleeve and bearing assembly; R5, after assembly, performs clearance verification and operational validation to restore the sliding bearing to its service capability.

[0049] Specifically, the reprocessing and repair of the replaceable functional journal sleeve in step R2 includes reforming the first and second functional micro-units, refilling with solid lubricating material, and finishing the outer surface; the recoating and repair of the bearing assembly in step R3 includes removing the failed coating, restoring or rebuilding the continuous interconnected non-through micro-anchoring structure, re-preparing the PAI-based composite coating, and curing and finishing it.

[0050] As can be seen, by setting the main functional surfaces on the replaceable functional journal sleeve 3, this embodiment helps to reduce the difficulty and cost of directly repairing the main shaft body, and improves the feasibility of on-machine maintenance and rapid resumption of operation of wind power equipment.

[0051] The working principle of this invention is as follows: 1) The continuous interconnected non-through micro-anchoring structure 21 differs from the traditional isolated pit-type adhesion pattern. This structure, through continuously interconnected shallow paths, allows the PAI-based composite coating 22 to form a more continuous mechanical interlocking network after curing. This facilitates the dispersion of interfacial stress under continuous in-plane shear loads, increases the actual bonding area, and enhances lateral locking capability. Compared to relying solely on localized point anchoring, this structure is more suitable for the interfacial adhesion requirements under heavy-load alternating wind power conditions.

[0052] 2) The first functional micro-unit 31 and the second functional micro-unit 32 of the present invention undertake different lubrication tasks respectively: the first functional micro-unit 31 is mainly responsible for oil storage and replenishment, and the second functional micro-unit 32 is mainly responsible for start-stop auxiliary lubrication. By assigning the two types of functions to different micro-units, instead of having a single texture undertake all functions at the same time, it is beneficial to avoid the problem of mutual encroachment between oil storage volume and solid lubrication filling space.

[0053] 3) Instead of arranging the two types of functional micro-units in a fixed circumferential macro-partition, this invention takes into account the working condition where the replaceable functional journal sleeve 3 rotates synchronously with the main shaft 1. It is preferred to distribute them in a periodically uniform mixed manner in the circumferential direction, and to set functional zones and edge restricted areas in the axial direction. This arrangement is more suitable for the working condition where the rotating surface passes through the lubrication inlet, load-bearing and outlet areas in sequence in each revolution cycle.

[0054] 4) This invention is primarily intended for heavy-load start-stop conditions in wind power systems, rather than being universally applicable to all sliding bearing structures. For low-speed heavy-load, alternating-load, and frequent start-stop conditions in wind turbines, this invention, by separating the compliant contact layer from the morphology-stabilizing functional layer, helps improve the long-term retention of lubrication regulation functions and ease of maintenance.

[0055] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus.

[0056] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A wind turbine main shaft sliding bearing with a PAI composite coating and a replaceable textured journal sleeve, characterized in that: It includes a main shaft (1), a bearing assembly (2) and a replaceable functional journal sleeve (3). The replaceable functional journal sleeve (3) is disposed on the outer periphery of the main shaft (1) and is fixedly connected to the main shaft (1) to rotate together. The bearing assembly (2) is disposed outside the replaceable functional journal sleeve (3). in, The bearing assembly (2) includes a bearing substrate, which forms a continuous interconnected non-through micro-anchoring structure (21) on the bearing working surface facing the replaceable functional journal sleeve (3), and the continuous interconnected non-through micro-anchoring structure (21) is covered with a PAI-based composite coating (22). The outer surface of the replaceable functional journal sleeve (3) is provided with a plurality of first functional micro-units (31) and second functional micro-units (32) spaced apart from each other. The first functional micro-unit (31) is an unfilled closed oil storage micro-pit, and the second functional micro-unit (32) is a closed lubrication micro-cavity filled with solid lubricating material. The PAI-based composite coating (22) and the outer surface of the replaceable functional journal sleeve (3) form a non-surface cooperative friction pair.

2. The wind turbine main shaft sliding bearing with PAI composite coating and replaceable textured journal sleeve according to claim 1, characterized in that: The PAI-based composite coating (22) is applied only to the working arc segment of the bearing assembly (2) and forms an edge recess area and / or a thickness gradient transition area in the edge region.

3. The wind turbine main shaft sliding bearing with PAI composite coating and replaceable textured journal sleeve according to claim 1, characterized in that: The replaceable functional journal sleeve (3) is connected to the main shaft (1) by one of the following: interference fit, hot fit, cold fit or tapered pressing fit, and is fixed by an axial limiting structure (33) and a circumferential anti-rotation structure.

4. The wind turbine main shaft sliding bearing with PAI composite coating and replaceable textured journal sleeve according to claim 1, characterized in that: The continuous interconnected non-through micro-anchoring structure (21) is grid-like, honeycomb-like, or curved interconnected.

5. The wind turbine main shaft sliding bearing with PAI composite coating and replaceable textured journal sleeve according to claim 1, characterized in that: The PAI-based composite coating (22) is a polyamide-imide resin-based composite coating containing one or more fillers selected from polytetrafluoroethylene, graphite, molybdenum disulfide, hexagonal boron nitride, zirconium oxide, carbon fiber, and ceramic particles.

6. The wind turbine main shaft sliding bearing with PAI composite coating and replaceable textured journal sleeve according to claim 1, characterized in that: The first functional micro-unit (31) has an equivalent size of 50-1000 μm and a depth of 5-150 μm; the second functional micro-unit (32) has an equivalent size of 30-500 μm and a depth of 5-80 μm.

7. The wind turbine main shaft sliding bearing with PAI composite coating and replaceable textured journal sleeve according to claim 1, characterized in that: The first functional micro-unit (31) and the second functional micro-unit (32) are distributed in a periodic and uniform mixed manner along the outer surface of the replaceable functional journal sleeve (3), and functional bands, low-density areas or edge restricted areas are set along the axial direction.

8. The wind turbine main shaft sliding bearing with PAI composite coating and replaceable textured journal sleeve according to claim 1, characterized in that: The replaceable functional journal sleeve (3) is an integral sleeve structure or a split sleeve structure; the bearing assembly (2) is a split structure, including an upper bearing and a lower bearing, which together form a sliding support hole that cooperates with the replaceable functional journal sleeve (3).

9. A method for manufacturing a wind turbine main shaft sliding bearing with a PAI composite coating and a replaceable textured journal sleeve as described in any one of claims 1 to 8, characterized in that, Includes the following steps: S1, a continuous interconnected non-penetrating micro-anchoring structure is formed on the surface of the bearing substrate; S2, the bearing substrate with the continuous interconnected non-through micro-anchoring structure is degreased, roughened, cleaned and subjected to necessary interface treatment; S3, selectively prepare a PAI-based composite coating on the working arc segment of the continuous interconnected non-through micro-anchoring structure, and retain the edge relief area; S4, the PAI-based composite coating is subjected to staged curing and finishing treatment; S5, a first functional micro-unit and a second functional micro-unit are prepared on the outer surface of the replaceable functional journal sleeve, and solid lubricating material is filled into the second functional micro-unit; S6: Fix the replaceable functional journal sleeve (3) to the outer periphery of the main shaft (1); S7: Assemble the main shaft with the replaceable functional journal sleeve and the bearing assembly to form a sliding bearing.

10. A method for repairing a wind turbine main shaft sliding bearing with a PAI composite coating and a replaceable textured journal sleeve as described in any one of claims 1 to 8, characterized in that, Includes the following steps: R1 is used to detect and evaluate the wear condition of replaceable functional journal sleeves and bearing assemblies. R2, when the first functional micro-unit and / or the second functional micro-unit of the replaceable functional journal sleeve wears out and fails, the replaceable functional journal sleeve is disassembled and replaced or reprocessed for repair. R3, when the PAI-based composite coating is worn, partially delaminated or its performance degraded, the bearing assembly is recoated for repair or replaced entirely; R4, reassemble the repaired replaceable functional journal sleeve and bearing assembly; R5, after assembly, performs gap verification and operational validation.

Images