A water-lubricated bearing strip and a water-lubricated bearing

Abstract

The application discloses a kind of water lubrication bearing slat, including sequentially adhering rigid surface layer, elastic intermediate layer and rigid base layer in the direction of ship stern shaft, the elastic intermediate layer and the rigid base layer are formed with hydraulic chamber along the length direction of slat between, the hydraulic chamber is filled with flowable incompressible liquid.This application also discloses a kind of water lubrication bearing, including the water lubrication bearing slat of the application and bearing sleeve, the inner wall of the bearing sleeve is divided into upper non-load-bearing area and lower load-bearing area, and multiple water lubrication bearing slats are circumferentially attached to the load-bearing area of the bearing sleeve.The incompressible liquid in the elastic intermediate layer and the hydraulic chamber is synergistically combined to adaptively combine liquid pressure mechanism with rubber elastic deformation, which solves the problem of traditional rubber composite slat unable to balance high load and high deformation adaptability.

Description

Technical Field

[0001] This invention belongs to the field of bearing technology, and particularly relates to a slat bearing and a water-lubricated bearing. Background Technology

[0002] Water-lubricated stern bearings are a crucial component of ship propulsion shafting, primarily supporting the weight of the stern shaft and propeller while also providing vibration damping. Due to the combined effects of propeller thrust, shafting accessories, and its own weight, the stern shaft undergoes deflection and axis tilting, causing the equivalent point of application of the stern bearing's supporting force to shift towards the stern, resulting in severe uneven loading. Specifically, this manifests as a significantly increased load in the stern region and a correspondingly decreased load in the bow region. This uneven stress state severely impacts the stern bearing's performance. Therefore, in practical applications, water-lubricated stern bearings must balance high load-bearing capacity with high deformation adaptability.

[0003] Slat-type water-lubricated bearings are widely used in the stern shaft bearings of large ships due to their advantages such as easy disassembly and low maintenance costs. Ships with high requirements for vibration reduction performance often use rubber as the bearing material. To ensure ease of installation, these bearings typically employ a slat structure composed of rubber and plastic or metal composites.

[0004] Currently, there are two main types of rubber composite slats: one uses rubber as the friction surface, directly contacting the stern shaft; the other uses rubber as the middle layer, a low-friction plastic surface layer, and a metal or hard plastic bottom layer. The former, due to the larger deformable area of ​​the rubber, has strong deformation adaptability and can distribute load more evenly, with less off-center loading effect, but its overall load-bearing capacity is lower. The latter, while having a higher overall load-bearing capacity, suffers from limited free deformation space because the rubber deforms only through its limited side surface area, making it difficult to design for low stiffness, resulting in poor deformation adaptability and stress concentration under off-center loading conditions. In summary, neither of the existing rubber-type water-lubricated bearing structures can simultaneously achieve high load-bearing capacity and high deformation adaptability, limiting the maximization of water-lubricated bearing technology performance. Therefore, there is an urgent need for a slat-type water-lubricated bearing with high overall load-bearing capacity and strong deformation adaptability. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the deficiencies and defects mentioned in the background art above, and to provide a water-lubricated bearing slat with low deflection stiffness, high vertical stiffness, high load-bearing capacity and high deformation adaptability, as well as a water-lubricated bearing.

[0006] To solve the above-mentioned technical problems, the technical solution proposed by this invention is as follows:

[0007] A water-lubricated bearing slat includes a rigid surface layer, an elastic intermediate layer, and a rigid base layer sequentially bonded together along a direction away from the stern axis of a ship. A hydraulic chamber is formed between the elastic intermediate layer and the rigid base layer along the length of the slat, and the hydraulic chamber is filled with a flowable incompressible liquid. Its specific working principle is that the load borne by the water-lubricated bearing can be decomposed into a vertical translational load and a vertical deflection load, wherein the vertical deflection load is the main factor causing off-center loading, and the proportion of the vertical translational load increases with increasing rotational speed.

[0008] When the stern shaft operates at low speed, the deflection load accounts for a large proportion, and the end of the slats closer to the stern bears a larger load, resulting in greater compression deformation of the hydraulic chamber on that side. The end farther from the stern bears a smaller load, and the hydraulic chamber experiences less compression deformation. At this time, incompressible fluid can flow freely from the chamber with greater deformation to the hydraulic chamber with less deformation. The internal pressure of the hydraulic chamber is low, and the external load is mainly borne by the elastic intermediate layer. Because this elastic intermediate layer contains hydraulic chambers, and its interior is partially hollow, the overall deflection stiffness of the slats is low, thus enabling it to adapt well to the deflection load of the stern shaft and achieve uniform load bearing.

[0009] When the stern shaft rotates at high speed, the vertical dynamic load increases significantly. Under the action of the vertical load, the deformation at both ends of the hydraulic chambers along the length of the slats tends to be consistent, making it difficult for incompressible fluid to flow between the hydraulic chambers, thus creating high pressure within the hydraulic chambers. At this time, the external load is borne jointly by the elastic intermediate layer and the hydraulic pressure, and the overall stiffness of the slats is greatly improved, which can meet the high load-bearing requirements under high speed.

[0010] In the aforementioned water-lubricated bearing slats, preferably, the hydraulic chamber includes a plurality of first hydraulic chambers disposed at one end of the slat along its length, and a plurality of second hydraulic chambers disposed at the other end of the slat along its length. The plurality of first hydraulic chambers are interconnected, the plurality of second hydraulic chambers are interconnected, and the first hydraulic chambers and the second hydraulic chambers are interconnected through an intermediate flow channel. This arrangement, with multiple chambers distributed along the length, collectively constitutes a large-volume liquid chamber system, significantly enhancing the overall deformation capacity of the chamber under pressure. This not only provides ample space for liquid flow but also improves the pressure build-up and release efficiency of the hydraulic chambers under load, making the bearing more sensitive to dynamic loads and providing better buffering. This allows it to better cope with complex load changes during ship operation, improving the stability and reliability of the bearing.

[0011] In the aforementioned water-lubricated bearing slats, preferably, two first hydraulic chambers and two second hydraulic chambers are provided respectively. The two first hydraulic chambers are located in the middle region of the slat width direction, and the two second hydraulic chambers are located on both sides of the slat width direction. This layout ensures the continuity and consistency of the slat stiffness throughout its entire length, as well as the uniform alternation in the width direction, ensuring a continuous transition of stiffness throughout the entire slat width. Under stress, the deformation amplitude in each region is consistent, resulting in stronger overall stability and adaptability to complex loads.

[0012] In the aforementioned water-lubricated bearing slats, preferably, multiple interconnected first slots are provided between the first hydraulic chambers, and multiple interconnected second slots are provided between the second hydraulic chambers. An intermediate flow channel connects adjacent first and second slots. The first and second slots ensure free and rapid exchange of fluid between the hydraulic chambers on the same side. When the ship's stern shaft rotates, even at the same end of the slat, slight differences in load distribution can lead to uneven stress distribution in different chambers on the same side. The lack of a direct connection path between adjacent chambers prevents the fluid in the chamber with higher pressure from quickly transferring to the chamber with lower pressure, causing fluctuations in stiffness in the corresponding area of ​​the slat, resulting in abrupt stiffness changes and increasing the risk of local stress concentration. The first and second slots allow fluid to flow quickly to other chambers on the same side, instantly eliminating local pressure differences. This instantaneous balance avoids abrupt stiffness changes caused by localized fluid chamber pressure imbalances, making the stiffness distribution at the same end of the slat more uniform and further enhancing the continuity of overall stiffness.

[0013] In the aforementioned water-lubricated bearing slats, preferably, the widths of the first and second hydraulic chambers gradually decrease from the ends to the middle of the slats. This gradual narrowing of the chamber width from the ends to the middle creates a gradual stiffness transition structure. When the ends are subjected to larger eccentric loads, the chambers at the ends can undergo greater compressive deformation. Simultaneously, it effectively avoids stress concentration caused by abrupt changes in geometry and cross-sectional area between the chambers and the flow channels, allowing the stress generated by the load to be transmitted and distributed more smoothly along the length of the slats. It also provides a more directional flow channel for the internal liquid flow. When the chambers are pressurized, this structure helps guide the liquid to flow more orderly from wide cross-sectional areas to narrow cross-sectional areas, reducing dead zones and thus promoting pressure balance speed and efficiency between chambers on the same side and both sides, enhancing the bearing's self-adjusting capability.

[0014] In the aforementioned water-lubricated bearing slats, preferably, the lengths of both the first and second hydraulic chambers extend from the ends of the slats beyond the centerline along the length direction of the slats. This arrangement creates an overlapping chamber region in the middle of the slats, and with the chamber width gradually decreasing towards the middle of the slats, a smooth transition zone of stiffness is constructed in the middle region of the slats, ensuring the continuity of the compressive stiffness of the slats in the axial direction.

[0015] Preferably, in the aforementioned water-lubricated bearing strips, the bottom of the rigid base layer is provided with a sealing strip for overall sealing of the hydraulic chamber. By using independent sealing strips to achieve overall sealing at the bottom of the rigid base layer, compared to other complex sealing methods, such as sealing each chamber individually, it is easier to process, manufacture, and assemble, simplifying the process, reducing manufacturing costs, and reducing potential leakage points, thereby improving the reliability and consistency of the seal from a design perspective.

[0016] As a general technical concept, this invention also provides a water-lubricated bearing, including the aforementioned water-lubricated bearing slats and a bearing sleeve. The inner wall of the bearing sleeve is divided into an upper non-load-bearing area and a lower load-bearing area. Multiple water-lubricated bearing slats are attached to the load-bearing area circumferentially along the bearing sleeve. This arrangement divides the inner wall of the bearing sleeve into an upper non-load-bearing area and a lower load-bearing area based on the nature of the load borne by the inner wall under normal operating conditions. The load-bearing area directly bears the radial pressure generated by the main loads such as the gravity of the stern shaft and its accessories, and the thrust of the propeller under normal operating conditions, and is the core area that bears the support function. The non-load-bearing area usually does not contact the journal or is only subjected to minimal pressure during normal operation. Its main functions are to form a complete lubrication channel, provide centering constraint for the shaft, and provide auxiliary support under extreme operating conditions. When the shaft system deflects or vibrates, each slat located in the load-bearing area can independently perform hydraulic adaptive adjustment according to the local pressure it bears, thereby working together to efficiently disperse and homogenize the concentrated load, greatly improving the contact state between the journal and the bearing, and effectively avoiding extreme off-center loading and excessive local wear.

[0017] Preferably, the aforementioned water-lubricated bearing also includes conventional slats without hydraulic chambers, with multiple such slats circumferentially attached to the non-load-bearing area along the bearing sleeve. This arrangement avoids the use of expensive or complex high-performance water-lubricated bearing slats in the essentially unloaded non-load-bearing area, achieving optimized material configuration and significantly reducing manufacturing costs while ensuring excellent load-bearing performance.

[0018] In the aforementioned water-lubricated bearing, preferably, multiple water-lubricated bearing slats are arranged continuously along the length of the bearing sleeve. This arrangement, by dividing the bearing surface of the extra-long bearing sleeve into multiple standard-length slat modules and splicing them together, fundamentally solves the technical difficulties and high costs associated with casting, processing, transportation, and installation of integral extra-long slats. When the bearing is under load, each slat unit can independently undergo micro-deformation and hydraulic pressure adjustment according to its local pressure conditions, thereby decomposing the concentrated load and having multiple modules work together to bear it, resulting in a more uniform load distribution and higher load-bearing capacity.

[0019] Compared with the prior art, the advantages of the present invention are as follows:

[0020] This invention utilizes the synergistic effect of an elastic interlayer and the incompressible fluid in the hydraulic chamber to combine a fluid pressure adaptive mechanism with the elastic deformation of rubber. Under low-speed, off-center load conditions, the free flow of the fluid and the large deformation capacity of the elastic interlayer result in excellent compliance and load equalization, achieving low bearing deflection stiffness and effectively alleviating stress concentration. Under high-speed, heavy-load conditions, the hydraulic pressure in the hydraulic chamber and the elastic interlayer work together to achieve high vertical stiffness, significantly improving overall support stiffness and load-bearing capacity. This effectively solves the problem of traditional rubber composite strips being unable to balance high load-bearing capacity and high deformation adaptability, automatically adjusting support stiffness according to operating conditions, and significantly improving the overall performance and reliability of water-lubricated bearings, making it particularly suitable for large-size water-lubricated bearings. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the overall structure of the water-lubricated bearing strip in an embodiment.

[0023] Figure 2 A schematic diagram of the overall structure of the water-lubricated bearing strip from an overhead view, as shown in the embodiment;

[0024] Figure 3 This is a schematic diagram of the water-lubricated bearing strip from an overhead view (excluding the sealing strip) as an example.

[0025] Figure 4 This is a structural schematic diagram of the water-lubricated bearing strip from another upward angle (excluding the sealing strip) as an embodiment.

[0026] Figure 5This is a structural schematic diagram of the water-lubricated bearing strip from another upward angle (excluding the sealing strip) as an embodiment.

[0027] Figure 6 This is a schematic diagram of the overall structure of the water-lubricated bearing in an embodiment;

[0028] Figure 7 This is a schematic diagram illustrating the assembly of a water-lubricated bearing slat and a conventional slat, as shown in the embodiment.

[0029] Figure 8 This is a schematic diagram of the structure of a conventional slat in an embodiment.

[0030] Legend

[0031] 1. Rigid surface layer; 2. Elastic intermediate layer; 3. Rigid base layer; 4. Hydraulic chamber; 41. First hydraulic chamber; 42. Second hydraulic chamber; 43. Intermediate flow channel; 44. First slot; 441. First slot one; 442. First slot two; 443. First slot three; 45. Second slot; 451. Second slot one; 452. Second slot two; 453. Second slot three; 46. Sealing strip; 5. Bearing sleeve; 51. Non-load-bearing area; 52. Load-bearing area; 6. Conventional strip. Detailed Implementation

[0032] To facilitate understanding of the present invention, the present invention will be described more fully and in detail below with reference to the accompanying drawings and preferred embodiments, but the scope of protection of the present invention is not limited to the following specific embodiments.

[0033] It should be noted that when a component is described as being "fixed to, attached to, connected to or connected to" another component, it can be directly fixed to, attached to, connected to or connected to the other component, or it can be indirectly fixed to, attached to, connected to or connected to the other component through other intermediate connectors.

[0034] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention.

[0035] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this invention can be purchased from the market or prepared by existing methods.

[0036] Example:

[0037] like Figures 1 to 8As shown, the water-lubricated bearing strip of this embodiment includes a rigid surface layer 1, an elastic intermediate layer 2, and a rigid base layer 3 that are sequentially bonded together in the direction away from the stern shaft of the ship. A hydraulic chamber 4 is formed between the elastic intermediate layer 2 and the rigid base layer 3 along the length direction of the strip, and the hydraulic chamber 4 is filled with a flowable incompressible liquid.

[0038] In this embodiment, as Figures 3 to 5 As shown, the hydraulic chamber 4 includes a plurality of first hydraulic chambers 41 disposed at one end of the slat along the length of the slat, and a plurality of second hydraulic chambers 42 disposed at the other end of the slat along the length of the slat. The plurality of first hydraulic chambers 41 are interconnected with each other, the plurality of second hydraulic chambers 42 are interconnected with each other, and the first hydraulic chambers 41 and the second hydraulic chambers 42 are interconnected with each other through an intermediate flow channel 43.

[0039] In this embodiment, there are two first hydraulic chambers 41 and two second hydraulic chambers 42 respectively. The two first hydraulic chambers 41 are located in the middle area of ​​the width direction of the strip, and the two second hydraulic chambers 42 are located on both sides of the width direction of the strip.

[0040] In this embodiment, multiple interconnected first slots 44 are provided between the first hydraulic chambers 41, and multiple interconnected second slots 45 are provided between the second hydraulic chambers 42. An intermediate flow channel 43 connects adjacent first slots 44 and second slots 45. Specifically, the first slots 44 and second slots 45 are formed at the bottom of the rigid base layer 3, and there are three first slots 44, namely first slot one 441, first slot two 442, and first slot three 443, and three second slots 45, namely second slot one 451, second slot two 452, and second slot three 453. An intermediate flow channel 43 connects first slot three 443 and second slot three 453.

[0041] In this embodiment, the widths of the first hydraulic chamber 41 and the second hydraulic chamber 42 gradually decrease from the end of the slat to the middle of the slat.

[0042] In this embodiment, the lengths of both the first hydraulic chamber 41 and the second hydraulic chamber 42 extend from the end of the slat across the centerline of the slat length direction.

[0043] In this embodiment, as Figure 2 As shown, the bottom of the rigid base layer 3 is provided with a sealing strip 46 for overall sealing of the hydraulic chamber 4.

[0044] In this embodiment, specifically, the rigid surface layer 1 is made of high-wear-resistant, low-friction plastic, which reduces the coefficient of friction and improves wear resistance; the elastic intermediate layer 2 is made of highly elastic rubber, which coordinates deformation and reduces vibration; and the rigid base layer 3 is made of high-modulus, high-strength plastic, which provides supporting rigidity. In other embodiments, depending on the actual situation, the rigid surface layer 1 can be made of other high-wear-resistant, low-friction materials, the elastic intermediate layer 2 can be made of other highly elastic materials, and the rigid base layer 3 can be made of other high-modulus, high-strength materials.

[0045] The water-lubricated bearing in this embodiment, such as Figures 6 to 8 As shown, it includes water-lubricated bearing strips and bearing sleeve 5. The inner wall of the bearing sleeve 5 is divided into an upper non-load-bearing area 51 and a lower load-bearing area 52. Multiple water-lubricated bearing strips are attached to the load-bearing area 52 along the circumference of the bearing sleeve 5.

[0046] In this embodiment, a conventional strip 6 without a hydraulic chamber 4 is also included, with multiple conventional strips 6 attached circumferentially along the bearing sleeve 5 to the non-load-bearing area 51. The conventional strips 6 are composite strips made of the same material as the water-lubricated bearing strips.

[0047] In this embodiment, multiple water-lubricated bearing strips are continuously arranged along the length of the bearing sleeve 5. Specifically, end caps are provided at both ends of the bearing sleeve 5 to position the strips. The inner wall of the bearing sleeve 5 is provided with multiple dovetail grooves along the circumference. The water-lubricated bearing plates and conventional strips 6 are connected to the dovetail grooves with an interference fit. Three continuous water-lubricated bearing strips or conventional strips 6 are arranged in a single dovetail groove. In other embodiments, the number of strips in a single dovetail groove can be set according to the actual situation.

[0048] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A water-lubricated bearing slat, comprising a rigid surface layer (1), an elastic intermediate layer (2), and a rigid base layer (3) sequentially bonded together along a direction away from the stern shaft of a ship, characterized in that, A hydraulic chamber (4) is formed between the elastic intermediate layer (2) and the rigid base layer (3) along the length of the slats, and the hydraulic chamber (4) is filled with a flowable incompressible liquid; The hydraulic chamber (4) includes a plurality of first hydraulic chambers (41) located at one end of the slat along the length of the slat, and a plurality of second hydraulic chambers (42) located at the other end of the slat along the length of the slat. The plurality of first hydraulic chambers (41) are interconnected with each other, and the plurality of second hydraulic chambers (42) are interconnected with each other. The first hydraulic chambers (41) and the second hydraulic chambers (42) are interconnected with each other through an intermediate flow channel (43). The first hydraulic chamber (41) and the second hydraulic chamber (42) are provided in two places respectively. The two first hydraulic chambers (41) are located in the middle area of ​​the width direction of the strip, and the two second hydraulic chambers (42) are located on both sides of the width direction of the strip respectively. The first hydraulic chambers (41) are provided with a plurality of connected first slots (44), and the second hydraulic chambers (42) are provided with a plurality of connected second slots (45). The intermediate flow channel (43) is connected between adjacent first slots (44) and second slots (45). The width of the first hydraulic chamber (41) and the second hydraulic chamber (42) gradually decreases from the end of the slat to the middle of the slat.

2. The water-lubricated bearing strip according to claim 1, characterized in that, The lengths of the first hydraulic chamber (41) and the second hydraulic chamber (42) both extend from the end of the slat across the centerline of the slat length direction.

3. The water-lubricated bearing strip according to claim 1 or 2, characterized in that, The bottom of the rigid base layer (3) is provided with a sealing strip (46) for sealing the hydraulic chamber (4) as a whole.

4. A water-lubricated bearing, characterized in that, Includes water-lubricated bearing strips as described in any one of claims 1-3 and bearing sleeve (5), wherein the inner wall of the bearing sleeve (5) is divided into an upper non-load-bearing area (51) and a lower load-bearing area (52), and multiple water-lubricated bearing strips are attached to the load-bearing area (52) circumferentially along the bearing sleeve (5).

5. The water-lubricated bearing according to claim 4, characterized in that, It also includes conventional strips (6) without hydraulic chamber (4), and multiple conventional strips (6) are attached to the non-load-bearing area (51) along the circumference of the bearing sleeve (5).

6. The water-lubricated bearing according to claim 4, characterized in that, Multiple water-lubricated bearing strips are arranged continuously along the length of the bearing sleeve (5).

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