Manufacturing method of three-layer composite self-lubricating shell bearing used in inner curve hydraulic motor

Abstract

The present invention provides a method for manufacturing a three-layer composite self-lubricating shell bearing for use in an internal curve hydraulic motor. [Solution] In the technical field of hydraulic parts, the self-lubricating layer of a three-layer composite self-lubricating shell bearing is modified by arranging self-lubricating layers with different parameters to obtain multiple reinforced self-lubricating layers, and ring samples of the self-lubricating layer are processed. A reinforced group with a small friction coefficient and small wear amount is selected through friction and wear tests, and simulation parameters of the three-layer composite self-lubricating shell bearing are obtained through measurement of material performance, a simulation parameter model of the three-layer composite self-lubricating shell bearing is created, and the stress distribution of the three-layer composite self-lubricating shell bearing is calibrated and the thickness is designed. Real shell bearing samples are processed, and actual operating conditions are simulated and measured, and selection is made while verifying the simulation results.

Description

[Technical field]

[0001] The present invention relates to the technical field of hydraulic components, and in particular to a manufacturing method for a three-layer composite self-lubricating shell bearing used in an internal curve hydraulic motor. [Background technology]

[0002] The three-layer composite self-lubricating shell bearing is located in the plunger part of the internal curve motor, and is mainly used to play the role of lubrication between the roller and the plunger when the lubrication condition is poor. When the internal curve motor is running, the force generated by the hydraulic pressure pushes the plunger part radially, and the tangential component of the reaction force of the internal curve against the plunger part provides the output torque to the motor shaft. The reaction force of the internal curve is applied to the roller, and the roller transmits the force to the inner surface of the plunger through the shell bearing, so the mechanical performance of the shell bearing must meet the maximum load of the internal curve motor in the operating condition of overload. It is therefore necessary to carry out a mechanical analysis of the shell bearing, optimize its mechanical performance, and increase the shell bearing load.

[0003] For the internal curve hydraulic motor, when the roller and plunger pair are in a low speed operating condition during operation, the lubrication performance is poor. When the motor is operating at a low speed, the lubrication state between the rollers is between solid friction and boundary lubrication. In addition, when the shell bearing is acted upon by alternating load, the force applied to the roller and plunger pair becomes complicated. Therefore, it is a technical problem to study the performance of suppressing friction and wear for the roller and plunger pair. Summary of the Invention [Problem to be solved by the invention]

[0004] In the prior art, the design of the internal curved shell bearing generally adopts a single-layer or two-layer composite structure, while it is rare to adopt a shell bearing with a three-layer composite structure. In addition, there is currently no clear design method for the shell bearing structure design and the design of the self-lubricating layer parameters of the shell bearing. [Means for solving the problem]

[0005] In response to the problems existing in the prior art, the present invention provides a method for manufacturing a three-layer composite self-lubricating shell bearing for an internal curve hydraulic motor, which is a method for manufacturing a three-layer composite self-lubricating shell bearing that combines configuration design and parameter modification. First, the self-lubricating layer of the three-layer composite self-lubricating shell bearing is modified by arranging self-lubricating layers with different parameters, and a plurality of reinforced self-lubricating layer materials are obtained, and the simulation parameters are obtained through friction wear test and material performance measurement. Secondly, for the three-layer composite self-lubricating shell bearing, the stress distribution is calibrated and the thickness is designed, and an optimized three-layer composite self-lubricating shell bearing is obtained through simulation measurement of the actual operating situation. Then, the indicator of the service life of the internal curve motor can be improved, and a suitable and wear-resistant three-layer composite self-lubricating shell bearing can be obtained through the configuration parameters of the roller and plunger of different internal curve hydraulic motors.

[0006] The manufacturing method of the three-layer composite self-lubricating shell bearing for the inner curve hydraulic motor provided by the present invention is specifically implemented as follows: Step S1: based on the operating conditions of the internal curve hydraulic motor being low speed and overload, the self-lubricating layer of the three-layer composite self-lubricating shell bearing is modified by the self-lubricating layer materials arranged with different parameters to obtain enhanced multiple self-lubricating layers, and includes the following sub-steps: Sub-step S11 is to sequentially add polytetrafluoroethylene and potassium titanate whiskers, which are solid lubricants, to polyetheretherketone and obtain a mixed intermediate product by mechanical stirring, the mixed intermediate product containing polyetheretherketone with a mass percentage of 75%, polytetrafluoroethylene with a mass percentage of 10%, and potassium titanate whiskers with a mass percentage of 15%. In sub-step S12, a silane coupling agent is added to the mixed intermediate product obtained in step S11 to reduce the amount of coacervate in the mixed intermediate product to obtain a modified self-lubricating layer material, which contains only 99% of the mixed intermediate product and only 1% of the silane coupling agent. Sub-step S13 adds different proportions of fibers, inorganic materials, and metal oxides to the modified self-lubricating layer material obtained in step S12 to obtain a reinforced self-lubricating layer material. The fibers include short carbon fibers and glass fibers. The inorganic materials include silicon dioxide and titanium oxide. The metal oxides include calcium carbonate whiskers and aluminum oxide. Step S2: According to the plurality of reinforced self-lubricating layer materials of step S1, a plurality of reinforced self-lubricating layer ring samples are correspondingly processed, a friction wear test is performed, and a friction wear experiment analysis is performed on the plurality of reinforced self-lubricating layer ring samples tested, and a self-lubricating layer material with a small friction coefficient and a small amount of wear is selected. The friction wear test analysis includes friction coefficient, wear rate and surface appearance analysis. Step S3: measure the material performance of the three-layer composite self-lubricating shell bearing including the self-lubricating layer material with small friction coefficient and small wear amount obtained in step S2, and obtain the simulation parameters of the three-layer composite self-lubricating shell bearing. The simulation parameters of the three-layer composite self-lubricating shell bearing include yield strength, density, Young's modulus and Poisson's ratio. Step S4 creates a constitutive model consisting of a roller, a shell bearing and a plunger in the simulation parameters of the three-layer composite self-lubricating shell bearing obtained in step S3. Step S5: based on the simulation parameters of the three-layer composite self-lubricating shell bearing obtained by step S3, and based on step S4, performs stress distribution calibration and thickness design for the three-layer composite self-lubricating shell bearing, including the following sub-steps: Step S51: when the operating condition is one in which dynamic load is taken into consideration, obtain the load at which the self-lubricating layer in the three-layer composite self-lubricating shell bearing is at the maximum operating pressure through simulation analysis. Step S52 identifies the thickness range of each layer in the three-layer composite self-lubricating shell bearing. The thickness of the three-layer composite self-lubricating shell bearing as a whole obtained by the constitutive model of roller, shell bearing and plunger obtained in step S4 is 1-2mm. According to the thickness of the three-layer composite self-lubricating shell bearing as a whole, the thickness of the back steel and the self-lubricating layer copper powder layer in the three-layer composite self-lubricating shell bearing are grouped, and the predetermined distribution proportion range of each layer thickness in the three-layer composite self-lubricating shell bearing is obtained by simulation optimization. Step S6: According to the reinforced self-lubricating layer material obtained in step S1 and the predetermined distribution ratio range of each layer thickness in the three-layer composite self-lubricating shell bearing obtained in step S5, process a three-layer composite self-lubricating shell bearing sample, and use roller-shell bearing type friction wear tester to carry out actual operating situation simulation measurement on the three-layer composite self-lubricating shell bearing sample, obtain an optimized three-layer composite self-lubricating shell bearing. In the optimized three-layer composite self-lubricating shell bearing, the thickness of the self-lubricating layer is 0.1-0.2mm, the thickness of the copper powder layer is 0.15-0.25mm, and the thickness of the back steel is 1.05-1.25mm.

[0007] Preferably, the device required for the friction and wear test in step S2 is a ring-type friction and wear test instrument, and the rolling bearing steel GCr15SiMn is selected to simulate the roller of a motor by using the rolling bearing steel, and the reinforced self-lubricating layer material is used to simulate the self-lubricating layer of a three-layer composite self-lubricating shell bearing.

[0008] Preferably, in step S5, the thicknesses of the back steel are set to 0.9 mm, 1.0 mm, 1.1 mm, 1.2 mm and 1.3 mm, respectively, the thickness of the self-lubricating layer is smaller than the thickness of the copper powder layer, and the difference between the thickness of the self-lubricating layer and the thickness of the copper powder layer is 0.1 mm-0.15 mm.

[0009] Preferably, the three-layer composite self-lubricating shell bearing has a copper powder layer made of copper alloy powder CuSn8Zn3, and a back steel made of cold-rolled carbon steel sheet and strip.

[0010] Preferably, in step S6, the testing machine is a roller-shell bearing type friction and wear test measuring machine. Effect of the Invention

[0011] The present invention has the following advantages over the prior art: 1. The present invention selects a three-layer composite self-lubricating shell bearing configuration containing reinforced self-lubricating layer material, thereby conducting a mechanical analysis of the three-layer composite self-lubricating shell bearing and optimizing its mechanical performance, so as to efficiently increase the load of the three-layer composite self-lubricating shell bearing and meet the maximum load of the internal curve motor under the operating condition of overload.

[0012] 2. The present invention adds solid lubricants and coupling agents to the reinforced self-lubricating layer material, and selects a relatively systematic selection form from several modification methods. By combining friction and wear tests with actual test simulation, the results are more accurate. The reinforced self-lubricating layer material can be applied to the simulation calibration of three-layer composite self-lubricating shell bearings to improve the lubrication performance.

[0013] 3. The present invention provides an oil pump for the friction and wear test, which can circulate the oil and reduce the temperature during the friction and wear test. [Brief description of the drawings]

[0014] [Figure 1] 2 is a flow chart showing a method for manufacturing a three-layer composite self-lubricating shell bearing used in an internal curve hydraulic motor according to the present invention. [Diagram 2] FIG. 2 is a diagram showing the configurations of the roller, shell bearing and plunger in the manufacturing method of the three-layer composite self-lubricating shell bearing used in the internal curve hydraulic motor according to the present invention. [Diagram 3] FIG. 2 is a diagram showing the configuration of a three-layer composite self-lubricating shell bearing in the manufacturing method of a three-layer composite self-lubricating shell bearing used in an internal curve hydraulic motor according to the present invention. [Figure 4] FIG. 2 is a diagram showing a friction and wear tester and an oil pump in the manufacturing method of a three-layer composite self-lubricating shell bearing used in an internal curve hydraulic motor according to the present invention. [Diagram 5] FIG. 2 is a diagram showing the simulated stress change of a three-layer composite self-lubricating shell bearing in the manufacturing method of the three-layer composite self-lubricating shell bearing used in the internal curve hydraulic motor according to the present invention; [Figure 6] FIG. 2 is a front view of a three-layer composite self-lubricating shell bearing used in an internal curve hydraulic motor according to the present invention; [Figure 7] FIG. 2 is an enlarged view of a three-layer composite self-lubricating shell bearing used in an internal curve hydraulic motor according to the present invention; [Figure 8] FIG. 2 is a curve showing the friction coefficient of the ring disc friction wear test of the three-layer composite self-lubricating shell bearing, which is used in the internal curve hydraulic motor of the present invention and is manufactured by adding only 15% short carbon fiber. [Figure 9] FIG. 2 is a curve diagram showing the friction coefficient of the simulated measurement of the actual operating conditions of a three-layer composite self-lubricating shell bearing using an internal curve hydraulic motor according to the present invention, in which only 15% short carbon fiber is added in the manufacturing method of the three-layer composite self-lubricating shell bearing. [Figure 10] FIG. 2 is a curve diagram showing the friction coefficient of the simulated measurement of the actual operating conditions of the three-layer composite self-lubricating shell bearing, which is used in the internal curve hydraulic motor of the present invention and is manufactured by adding only 15% glass fiber. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to explain the technical contents, objectives and effects of the present invention, a detailed description will be given below with reference to the drawings in the specification.

[0016] Specifically, the manufacturing method of the three-layer composite self-lubricating shell bearing for the inner curve hydraulic motor provided by the present invention includes a self-lubricating layer 21, a copper powder layer 22 and a back steel 23, as shown in Figure 3, Figure 6 and Figure 7, the copper powder layer 22 is copper alloy powder (CuSn8Zn3), the back steel 23 is cold rolled carbon steel sheet and strip (sppc), the self-lubricating layer 21 is reinforced self-lubricating layer material, including modified self-lubricating layer material and different types and proportions of fiber / inorganic material / metal oxide filled. As shown in Figure 1, the manufacturing method of the three-layer composite self-lubricating shell bearing for the inner curve hydraulic motor includes two main designs, namely, a self-lubricating layer with different parameters and a shell bearing composed of three layers, and the specific manufacturing process is realized as follows:

[0017] Step S1: According to the low speed and overload operating conditions of the inner curve hydraulic motor, the self-lubricating layer of the three-layer composite self-lubricating shell bearing is modified by the self-lubricating layer material with different parameters to obtain a plurality of reinforced self-lubricating layers. Among them, the implementation steps of the self-lubricating layer of the three-layer composite self-lubricating shell bearing is modified by the self-lubricating layer material with different parameters as follows:

[0018] In step S11, polytetrafluoroethylene (PTFE) and potassium titanate whiskers (PTW), which are solid lubricants, are added to polyether ether ketone (PEEK) in sequence, and a mixed intermediate product is obtained by mechanical stirring.

[0019] In step S12, since polymerization phenomenon occurs frequently in the mixed intermediate product, a silane coupling agent KH550 is added to the mixed intermediate product obtained in step S11 to reduce the amount of coacervate in the mixed intermediate product, and the mixed intermediate product is observed under a microscope from the perspective of the size and quantity of the coacervate to see whether there is any obvious coacervate in the mixed intermediate product, and a modified self-lubricating layer material is obtained.

[0020] Step S13 adds different proportions of fibers, inorganic materials, and metal oxides to the modified self-lubricating layer material obtained by step S12 to obtain a plurality of reinforced self-lubricating layer materials. Specifically, the fibers include short carbon fibers and glass fibers. The short carbon fibers are arranged in different proportions of 5%, 10%, 15%, and 20% by mass, respectively, and the glass fibers are arranged in different proportions of 15%, 20%, 25%, 30%, and 35% by mass, respectively. The inorganic materials include silicon dioxide and titanium oxide. The silicon dioxide is arranged in different proportions of 1%, 2%, 3%, 4%, and 5% by mass, respectively, and the titanium oxide is arranged in different proportions of 5%, 10%, 15%, and 20% by mass, respectively. The metal oxides include calcium carbonate whiskers and aluminum oxide. The calcium carbonate whiskers are arranged in different mass percentages of 5%, 10%, 15%, 20%, 25% and 30%, respectively, and the aluminum oxide is arranged in different mass percentages of 1%, 2%, 3%, 4% and 5%, respectively.

[0021] Step S2: According to the reinforced self-lubricating layer materials obtained in step S1, a ring sample of the self-lubricating layer is processed correspondingly, and a friction wear test is performed on the tested reinforced self-lubricating layer ring samples, and a self-lubricating layer material with a low friction coefficient and a low wear amount is selected in this test. Specifically, the device required for the friction wear test is a ring-type friction wear tester, and the roller 1 of the motor is simulated by the rolling bearing steel (GCr15SiMn), and the reinforced self-lubricating layer material is simulated by the self-lubricating layer of the three-layer composite self-lubricating shell bearing. The analysis in the friction wear test includes the friction coefficient, wear rate and surface appearance, and can be obtained by devices such as a confocal microscope, a SEM scanning electron microscope, and an energy spectrometer. In addition, the friction wear test includes a friction wear tester 4 and an oil pump 5, and the oil pump 5 can circulate oil during the friction wear test to achieve the purpose of reducing the temperature, as shown in FIG. 4.

[0022] Step S3 measures the material performance of the three-layer composite self-lubricating shell bearing including the self-lubricating layer that meets the initial requirements, and obtains the simulation parameters of the three-layer composite self-lubricating shell bearing. Specifically, the material performance measurement includes yield strength, density, Young's modulus and Poisson's ratio.

[0023] Step S4, as shown in FIG. 2, creates a constitutive model consisting of a roller 1, a shell bearing 2 and a plunger 3 based on the simulation parameters of the three-layer composite self-lubricating shell bearing obtained in step S3, and identifies the configuration of the three-layer composite self-lubricating shell bearing and the materials of each layer.

[0024] Step S5: Based on the simulation parameters of the three-layer composite self-lubricating shell bearing obtained by step S3, perform stress distribution calibration and thickness design for the three-layer composite self-lubricating shell bearing based on step S4. Based on the simulation parameters (yield strength, density, Young's modulus and Poisson's ratio) mentioned in this embodiment, designing the thickness of the shell bearing means that those skilled in the art can generally apply some related simulation parameters to the shell bearing simulation design, so although the simulation step is not described, it does not affect the implementation of the technical solution of the present application. In this field, the software for simulating and analyzing mechanical parts includes various simulation analysis software, but it is not necessary to have only one or two simulation analysis software to realize the simulation and parameter analysis of the present application.

[0025] Step S6: According to the reinforced self-lubricating layer material obtained in step S1 and the predetermined distribution ratio range of each layer thickness in the three-layer composite self-lubricating shell bearing obtained in step S5, process a three-layer composite self-lubricating shell bearing sample, and carry out simulation measurement of actual working condition on the three-layer composite self-lubricating shell bearing sample to obtain an optimized three-layer composite self-lubricating shell bearing. In another preferred embodiment of the present invention, the device used for simulation measurement of actual working condition is a roller-shell bearing type friction wear tester, and in the optimized three-layer composite self-lubricating shell bearing, the thickness of the self-lubricating layer is 0.1-0.2mm, the thickness of the copper powder layer is 0.15-0.25mm, and the thickness of the back steel is 1.05-1.25mm.

[0026] In addition, in step S5, the specific process of calibrating the stress distribution and designing the thickness of the three-layer composite self-lubricating shell bearing includes the following steps:

[0027] Step S51: obtain the load of the self-lubricating layer at the maximum operating pressure in the three-layer composite self-lubricating shell bearing through simulation analysis in the operating state considering the dynamic load.

[0028] Step S52 identifies the thickness range of each layer in the three-layer composite self-lubricating shell bearing. Based on the configuration model of the roller 1, shell bearing 2 and plunger 3 obtained in step S4, the thickness of the entire three-layer composite self-lubricating shell bearing is 1.5 mm. According to the thickness of the entire three-layer composite self-lubricating shell bearing, the thickness of each layer in the three-layer composite self-lubricating shell bearing is grouped, and the thickness of the back steel 23 is set to 0.9 mm, 1.0 mm, 1.1 mm, 1.2 mm and 1.3 mm, respectively, the thickness of the self-lubricating layer 21 is set to be smaller than the thickness of the copper powder layer 22, and the difference between the thickness of the self-lubricating layer 21 and the thickness of the copper powder layer 22 is 0.1 mm-0.15 mm. By setting the back steel 23, the self-lubricating layer 21 and the copper powder layer 22 with different thicknesses, optimization is performed according to simulation to obtain the predetermined distribution proportional range of the thickness of each layer in the three-layer composite self-lubricating shell bearing.

[0029] The manufacturing method of the three-layer composite self-lubricating shell bearing used in the internal curve hydraulic motor according to the present invention will be further described below with reference to the following examples.

[0030] Step S1: According to the operating conditions of the inner curve hydraulic motor being low speed and overload, the self-lubricating layer of the three-layer composite self-lubricating shell bearing is modified by the self-lubricating layer with different parameters to obtain multiple strengthened self-lubricating layers. The specific operation process is as follows:

[0031] In step S11, the solid lubricant polytetrafluoroethylene (PTFE) and potassium titanate whisker (PTW) are sequentially added to the polyether ether ketone (PEEK), mixed and modified together, and a mixed intermediate product is obtained through mechanical stirring.

[0032] In step S12, since polymerization phenomenon occurs greatly in the mixed intermediate product, a silane coupling agent KH550 is added to the mixed intermediate product obtained in step S11 to reduce the amount of coacervate in the mixed intermediate product, and the mixed intermediate product is observed under a microscope from the perspective of the size and quantity of the coacervate to see whether there is obvious coacervate in the mixed intermediate product, and a modified self-lubricating layer material is obtained, which is specifically grouped into a mixed intermediate product containing only 99% and a silane coupling agent containing only 1%.

[0033] Step S13 adds 15% short carbon fibers and 15% glass fibers to the modified self-lubricating layer materials obtained by step S12 to obtain a number of reinforced self-lubricating layer materials.

[0034] Step S2: Based on the reinforced self-lubricating layer materials obtained in step S1, the ring samples of the self-lubricating layer are processed correspondingly, and a friction and wear test is performed, and the tested ring samples of the self-lubricating layer are analyzed. First, the surface appearance diagram and the wear trace diagram are taken by a confocal microscope, and the average wear trace is calculated. Next, the surface appearance is taken by a more accurate SEM scanning electron microscope and an energy dispersive X-ray spectroscopy instrument, and the energy of the components in the expression is scanned, and the self-lubricating layer with a small friction coefficient and a small amount of wear in this test is selected.

[0035] Step S3 measures the material performance of a three-layer composite self-lubricating shell bearing with a self-lubricating layer that meets the initial requirements, and obtains simulation parameters of the three-layer composite self-lubricating shell bearing.

[0036] Step S4, as shown in FIG. 2, uses the simulation software to create a constitutive model of roller 1-shell bearing 2-plunger 3 based on the simulation parameters of the three-layer composite self-lubricating shell bearing obtained in step S3.

[0037] Specifically, the strength of the single-layer shell bearing is weak, and therefore it cannot provide sufficient strength for the roller 1 when the internal curve hydraulic motor is actually working, so a three-layer composite self-lubricating shell bearing is adopted. The materials of each layer in the three-layer composite self-lubricating shell bearing are: the self-lubricating layer 21 is polyetheretherketone PEEK, the copper powder layer 22 is copper alloy powder CuSn8Zn3, and the back steel 23 is cold-rolled carbon steel sheet and steel strip sppc.

[0038] Step S5: calibrate the stress distribution and design the thickness of the three-layer composite self-lubricating shell bearing based on the simulation parameters of the three-layer composite self-lubricating shell bearing obtained in step S3 and based on step S4.

[0039] In step S51, in the operating condition considering the dynamic load, the load of the self-lubricating layer of the three-layer composite self-lubricating shell bearing at the maximum working pressure was analyzed by simulation, and the distribution of the stress from small to large became regular, as shown in FIG. 5, and the maximum stress value appeared on the axial end face of the cylindrical surface of the shell bearing.

[0040] Step S52 identifies the thickness range of each layer in the three-layer composite self-lubricating shell bearing. According to the roller 1-shell bearing 2-plunger 3 configuration model obtained by step S4, the thickness of the three-layer composite self-lubricating shell bearing as a whole is 1-2 mm. In a preferred embodiment, the thickness of the three-layer composite self-lubricating shell bearing as a whole is 1.5 mm. According to the thickness of the three-layer composite self-lubricating shell bearing as a whole, the thickness of each layer in the three-layer composite self-lubricating shell bearing is grouped. By setting the back steel 23, the self-lubricating layer 21 and the copper powder layer 22 with different thicknesses, a predetermined distribution proportion range is obtained for each layer thickness in the three-layer composite self-lubricating shell bearing optimized by simulation.

[0041] Step S6: According to the predetermined distribution proportional range of each layer thickness in the three-layer composite self-lubricating shell bearing obtained in step S5, a three-layer composite self-lubricating shell bearing sample is processed together with the reinforced self-lubricating layer material in step S1. As shown in Figures 6 and 7, the actual operating conditions of the three-layer composite self-lubricating shell bearing sample are measured by simulation to obtain an optimized three-layer composite self-lubricating shell bearing.

[0042] Specific verification results of the above manufacturing method are as follows.

[0043] In the actual three-layer composite self-lubricating shell bearing, the position where it becomes ineffective coincides with the distribution position of the maximum stress in the equivalent stress diagram, and the stress distribution in step S51 is reasonable. The three-layer composite self-lubricating shell bearing with the thickness of the three-layer composite self-lubricating shell bearing in the predetermined distribution ratio has the best wear resistance performance, and thus it is verified that the predetermined distribution ratio range for the thickness of the three-layer composite self-lubricating shell bearing obtained by simulation in step S52 is reasonable. The friction coefficient curves of the three-layer composite self-lubricating shell bearing reinforced with 5%, 10%, 15% and 20% short carbon fiber in the ring disc friction wear test are shown in FIG. 8. Therefore, the three-layer composite self-lubricating shell bearing reinforced with 15% short carbon fiber has the best friction coefficient. The friction curves measured under the simulation of the actual operating conditions are shown in Figure 9 and Figure 10. Under the same operating conditions, the friction coefficient of the reinforced three-layer composite self-lubricating shell bearing with 15% short carbon fiber is lower than that of the reinforced three-layer composite self-lubricating shell bearing with 15% glass fiber. The reinforced three-layer composite self-lubricating shell bearing with 15% short carbon fiber has the best effect in the actual simulation test.

[0044] Therefore, the three-layer self-lubricating composite shell bearing, in which the thickness of the self-lubricating layer 21 is 0.1-0.2mm, the thickness of the copper powder layer 22 is 0.15-0.25mm, the thickness of the back steel 23 is 1.05-1.25mm, the material required for the self-lubricating layer 21 is only 85% (PEEK / PTFE / PTW / KH550) and only 15% short carbon fiber, the material required for the copper powder layer 22 is copper alloy powder CuSn8Zn3, and the back steel 23 is cold-rolled carbon steel sheet and steel strip sppc, has the best performance. Finally, it is possible to design and select a three-layer composite self-lubricating shell bearing having the best self-lubricating performance and wear resistance.

[0045] The above-described examples are merely illustrative of preferred embodiments of the present invention, and are not intended to limit the scope of the present invention. As long as they do not deviate from the spirit of the design of the present invention, those skilled in the art can make various modifications and improvements to the technical means of the present invention, and all of these modifications and improvements are within the scope of the patent protection of the present invention.

Claims

1. A method for manufacturing an optimized three-layer composite self-lubricating shell bearing, comprising three layers: a self-lubricating layer of a reinforced self-lubricating layer material with a predetermined thickness, a copper powder layer, and a back steel layer, Step S1: According to the operating conditions of the inner curve hydraulic motor, namely, low speed and overload, a mixed intermediate product of a plurality of self-lubricating layer materials is modified to obtain a modified self-lubricating layer material, and a plurality of additives are added to the modified self-lubricating layer material in different proportions to obtain a plurality of reinforced self-lubricating layer materials; A sub-step S11 of sequentially adding polytetrafluoroethylene and potassium titanate whiskers, which are solid lubricants, to polyether ether ketone and mechanically stirring the mixture to obtain the mixed intermediate product, the mixed intermediate product containing polyether ether ketone having a mass percentage of 75%, polytetrafluoroethylene having a mass percentage of 10%, and potassium titanate whiskers having a mass percentage of 15%; A sub-step S12 of adding a silane coupling agent to the mixed intermediate product obtained in the sub-step S11, and obtaining a mixed intermediate product with a reduced amount of coacervate as the modified self-lubricating layer material, the modified self-lubricating layer material containing 99% of the mixed intermediate product and 1% of the silane coupling agent; and A sub-step S13 is a step of adding fibers, inorganic materials, and metal oxides in different ratios to the modified self-lubricating layer material obtained in the sub-step S12 to obtain the reinforced multiple self-lubricating layer materials, the fibers including short carbon fibers and glass fibers, the inorganic materials including silicon dioxide and titanium oxide, and the metal oxides including calcium carbonate whiskers and aluminum oxide. Step S1 including: Step S2: for each of the plurality of reinforced self-lubricating layer materials obtained in step S1, a ring sample of the reinforced self-lubricating layer is correspondingly processed to a predetermined thickness, and a friction and wear test is performed; the ring sample of the reinforced self-lubricating layer is subjected to a friction and wear experiment analysis; and based on the results of the friction and wear test and the friction and wear experiment analysis, a self-lubricating layer material having a small friction coefficient and a small amount of wear is selected from the plurality of reinforced self-lubricating layer materials; the friction and wear test analysis includes friction coefficient, wear rate and surface appearance analysis; Step S3: performing material performance measurement on the three-layer composite self-lubricating shell bearing containing the reinforced self-lubricating layer material selected in step S2, and obtaining simulation parameters of the three-layer composite self-lubricating shell bearing, the simulation parameters of the three-layer composite self-lubricating shell bearing including yield strength, density, Young's modulus and Poisson's ratio; Step S4: creating a constitutive model of the roller, the shell bearing and the plunger in the simulation parameters of the three-layer composite self-lubricating shell bearing obtained in step S3; Step S5: According to the simulation parameters of the three-layer composite self-lubricating shell bearing obtained in step S3, and based on step S4, calibrate the stress distribution and design the thickness of the three-layer composite self-lubricating shell bearing; Sub-step S51, when the operating condition is one in which dynamic load is taken into consideration, obtain a load at which the self-lubricating layer in the three-layer composite self-lubricating shell bearing is at its maximum operating pressure through simulation analysis; And, Sub-step S52: determining the thickness range of each layer in the three-layer composite self-lubricating shell bearing, that is, the thickness of the entire three-layer composite self-lubricating shell bearing obtained by using the constitutive model consisting of the roller, shell bearing and plunger obtained in step S4 is 1-2 mm; according to the thickness of the entire three-layer composite self-lubricating shell bearing, the thicknesses of the back steel, the self-lubricating layer and the copper powder layer in the three-layer composite self-lubricating shell bearing are grouped, and the predetermined distribution proportional range of the thickness of each layer in the three-layer composite self-lubricating shell bearing is obtained through simulation optimization; Step S5 includes: Step S6 includes processing a three-layer composite self-lubricating shell bearing sample according to the reinforced self-lubricating layer material obtained in step S1 and the predetermined distribution proportional range of thickness of each layer in the three-layer composite self-lubricating shell bearing obtained in step S5, and using a test machine to perform simulation measurement of actual operating conditions on the three-layer composite self-lubricating shell bearing sample to obtain an optimized three-layer composite self-lubricating shell bearing; The manufacturing method of the three-layer composite self-lubricating shell bearing for the internal curve hydraulic motor is characterized in that, in the optimized three-layer composite self-lubricating shell bearing, the thickness of the self-lubricating layer is 0.1-0.2mm, the thickness of the copper powder layer is 0.15-0.25mm, and the thickness of the back steel is 1.05-1.25mm.

2. The method for manufacturing a three-layer composite self-lubricating shell bearing for an internal curve hydraulic motor according to claim 1, characterized in that in step S5, the thickness of the back steel is set to 0.9mm, 1.0mm, 1.1mm, 1.2mm and 1.3mm respectively, the thickness of the self-lubricating layer is smaller than the thickness of the copper powder layer, and the difference between the thickness of the self-lubricating layer and the thickness of the copper powder layer is 0.1mm-0.15mm.

3. The manufacturing method of the three-layer composite self-lubricating shell bearing for the internal curve hydraulic motor as claimed in claim 1, characterized in that the copper powder layer of the three-layer composite self-lubricating shell bearing is copper alloy powder CuSn8Zn3, and the back steel is cold-rolled carbon steel sheet and steel strip.

4. The method for manufacturing a three-layer composite self-lubricating shell bearing for an internal curve hydraulic motor as claimed in claim 1, characterized in that in step S6, the testing machine is a roller-shell bearing type friction and wear test machine.

Images